Cqqrls and Pigments for Rubber"'compounding

CRUDE RUB BER

AND

CO M P O UNDI NG NGREDI ENTS

A TEXT-BO O K O F

RUB B E R MANUF ACTURE

By HENRY c .

“P EARSON,

Editor of The I ndia Rubber World

A uthor of What I Saw in the Tropics ," “Rubber Tires ,

The Rubber Country of the Amazon,

”

“Rubber Machinery,” etc .

I

TH IRD s e rmon"

NEW YORKThe India Rubber P ub lishing Company

1918

CO P YRIGHT, 1899, B Y HENRY C. P EARSON .

COP YRIGHT, 1909, B Y HENRY C. P EA RSON .

COP YRIGHT, 1918, B Y HEN RY C. P EA RSON .

mrnftzflnrWilliam (5. (BulbsF O R MA N Y Y EA RS

P R IN C I P A L 0 1 TH E P UN CHA RD F R E E 5

A NDO VER . M A S S .

W HO F IRS T AW A KEN ED TH E A UTHO R ’S

E S T lN B O TA N Y A N D C H EM I S TRYTH I S VO LUM E I S A F F ECTIO N A TELY DED I

P REFACE.

S I N CE the first edition of this book appeared, almost twentyyears ago

,the rubber business has grown notably. New sources

O f rubber have beendeveloped in various parts of the world , andgrades O f rubber heretofore unknown have come into use. P lantation rubber, previously a negligible factor, has taken its placeas a regular and dominating product. P rog ress

‘

ih the reclaiming O f waste rubber of all sorts has been constant and of greatmagnitude. The industry at large preserves the same generaloutline as formerly, with perhaps the single exception O f themaking O f motor tires , to day the greatest division in rubber manufacture . O f new compounding ingredients there are many, ofsubstitutes a great variety, and of processes , good and bad , thousands . In the revision O i the book those o f a real or a suggestive value have been utilized . The general plan o f the bookhas not been altered . I t remains a dictionary O f compoundingfacts , an encyclopedia o f rubberfactory practice. I t i s for rubberfactory use and bespeaks for itsel f the same favor that itfound with the practical man when it first appeared .

The superiori ty of such a collection over the most comprehensive book of compounds doubtless will be apparent to theexpert manufacturer, for thi s reason : When a manufacturerbuys a set O f compounds— and most of them are purchasablehe invariably acqui res them not so much for use as for suggestion and comparison . The descriptions , therefore, of a greatmaj ority of the ingredients used in all lines of rubber compounding, and scores with which he may be unfamiliar, will beso suggestive to the practical man that new sets of compoundswill be secured , each partaking O f the individuality of the expert,and bearing the impress O f the line of work done in the factoryto which he i s attached , and wholly free from the taint of imitation or counterfeiting, which is the bane O f the purchasedsecret. I t i s felt that another point of superiority over the merecompound book will be found in the fact that no private formulasare given , those which are cited being typical rather than specific .

4 P REF A CEIn the ten years that have elapsed since the second edition

of this work appeared , great changes have taken place in rubberproduction and in processes o f manufacture. The rise anddominance of cultivated rubber, the use of accelerators , the pressure cure

,instead of the open dry heat , the progres s in syn

thetic rubber production , are but a few of these .In the compilation and rev1s1on of this book free use has

been made of English , German , and F rench standard technicalworks , as well as O f technical journals, such as The I ndia RubberWor ld

,The I ndia-Rubber and Gutta—P ercha Trades Journal

,Le

Caoutchouc et la Gutta P ereha,the Gummi-Zeitung , The Journal

of the S ociety of Chemical I ndus try , and others .The author takes pleasure in acknowledging his indebted

ness for helpful suggestions to skilled manufacturers and superintendents in both America and Europe , and to the followingdistinguished writers : P . G. W. Typke, William Thompson

,H . Grimshaw, W. Lascelles-Scott , F .R.

M .S .,Richard Gerner, M .E . ; Dr . C . P urcell Taylor,

Thomas B olas , F P rofessor D. E . Hughes , F .R .S

Granville H . Sharpe , Carl O tto Weber, P h .D. ; Lothar ,

E . Weber, P h .D. ; A . Camille , the late Dr . Eugene F . A . O bach,

P hilip Schidrowitz , P h.D. ; Dr . JosephTorrey, Dr . David Spence, P rofessor F rancis E rnest Lloy d ,Hubert L. Terry , Cuthbert Christy, and manyothers .

I have great pleasure also in gratefully acknowledging theassistance of members of my staff in the onerous work O f proo freading

,indexing

, etc . My thanks are also extended to WebsterNorris , S .B .,

for his work in the revision o f the technical andchemical portions O f the volume.

CO NTENTS .

P reface

CHA P TER I .

Crude Rubber, Chemical and P hys ical Characteristics . Sources O f

Supply. Grades : P ara, Central , A fr ican, and East Ind ianGums . O r ig in O f Trade Names. Botanical Detai ls. P lanta

CHA P TER I I .

Some Little Known Rubber s and Bastard or P seudo-Gums ; P ossibility of Development of Their Use in the Factory .

CHA P TER I I I .

Coagulation, Native Methods ; Chemica l System's, Mechanical Sy stems, Coagulating Machines , Smoking , O xy dases

CHA P TER IV.

Vulcanizing P rocesses and Ing redients , Sulphur,.

Antimony Sul

phides , and O ther Materials Used . Vulcani zing P ressuresand Temperatures . P lantation Hevea and the Optimum Cure .

CHA P TER V.

A ccelerator s, O rganic and InorganicCHA P TER VI .

Fil ler s and Ing red ients Used in Rubber Compounds ; Sources , P roperties , and Uses O f the Various Maten als

'

; Unusual Ing red ients

CHA P TER VI I .

Substitutes for Ind ia Rubber , Natural and A rtificialCHA P TER VI I I .

Substitutes for Hard Rubber and Gutta-P ercha, Including Cellu

lose P roducts

CHA P TER IX .

Res ins, Balsams , Gurns , Earth Waxes , and Gum-Like SubstancesUsed in Rubber Compound ing

54

6 CONTENTSCHA P TER X.

Color ing Matters. Blacks , Blues , Greens , Reds , Browns , Whites ,and O ther Colors in Hard and Soft Rubber

CHA P TER X I .

A cids , A lkalies, and Their Derivatives Used in Rubber ManufactureCHA P TER X I I .

Veg etagles, M ineral , and A nimal O i ls Used in Rubber Compounds

an

CHA P TER XI I I .Solvents Used in Commercial and P roofing Cements ; Their O rig in,

P roperties , and Methods of Use

CHA P TER X IV.

M iscel laneous P rocesses and Compounds for Use in the RubberFactory : Waterproofing Compounds ; Shower -proofing ; Deodor ization ; P reserving Rubber Goods. Shrinkag e of Rubber .

Tire Fi l lers and P uncture Fluids . .

CHA P TER X V.

Synthetic RubberCHA P TER X VI .

Vulcanization Without SulphurCHA P TER XVI I .

Reclaimed Rubber and I ts Uses

CHA P TER XVI I I .P hysical Tests and A nalys is of Crude and Vulcanized Rubber .

Specifications for Rubber Goods . Specific GravityCHA PTER X IX .

P rimary P rocesses, Divis ions in Rubber Manufacture, and Typical

CHA P TER XX .

Gutta-P ercha : I ts Sources, P roperties , Manipulation, and Uses ;Components O f Gutta-P ercha ; Vulcanization ; Gutta-P ercha1n Compounds ; Methods of

194

CHAP TER I .

CRUDE RUB B ER, CHEM ICA L A ND P HY S ICAL CHARACTERISTICS , SOURCES O F SUP P LY ,

ET CETERA .

I NDIA RUB BER i s hard to define in scient ific language . I ts

atomic structure is difficult to express , and means little when expressed . It i s a hydrocarbon, w ith the approximate formulaClo ; but some oxygen i s always present, which has ledsome to b el ieve that oxygen is a necessary constituent . A s arul e, however, the presence O f Oxygen i s cons idered injurious ,or a sign O f deterioration . Rubber is as readily attacked byoxygen as i s i ron , and as surely des troyed by it . The formulaCmH 1 6 i s O f too general a nature to be of value , s ince it coversrubbers O f widely different phys ical propert ies , and even ine ludes Gutta-percha . A more important chemical fact i s thatrubber i s extremely res i s tant , being solub le only in carbondisulphide , carbon tetrachloride , turpentine , ether, gasol ineand the l ike.

The physical properties of rubber are softnes s , toughnes s ,elastic ity

,imperm‘

eabi l ity , adhes ion and electrical res i s tance .I ts most characteri stic , but not most important property , i sthat it can b e repeatedly stretched to many times it s l ength ,returning each time to about its firs t dimensions . No othersubstance i s at al l comparab le to rubber in thi s particularproperty , though one or more of the other properti es are posses sed in turn by many other sub stances .

Rubber is derived chiefly from the milk or latex found inthe bark O f many trees

,sh rubs and vines , and to a certain extent

also in the fruit, leaves , soft wood , or roots . The great familiesof the Euphorbiaeece, in tropical America, and the Apocynacece,in tropical A f rica, furnish most o f the world’s rubber. The

A rtoearpacece, of Central America and the East I ndies , have a certain importance , and the Compos itce, A s clepiadacea

’ and perhapsother vegetable families contribute a certain amount. A ltogetherthere are some thousands of species O f trees , vines , bushes ,weeds , roots , and tubers which contain rubber ; but the Hevea,O f B razil , the Landolphia and F untumia, o f A frica , and ' the

7

GRADES O F CRUDE RUB B ER

Cas tilloa, of Central America , together furnish practically thewhole of the world’s rubber. The tropic s hold a vast storeof wild rubber ; but transportation , in these regions , i s sodiffi cult , and the growth of rubber trees under cult ivation sorapid

,that i t i s easier to grow rubber in acces sib le places than

to get i t out of the deeper forest s ; with the added advantagethat plantation rubber i s better prepared than would generallybe possibl e in the forest .

The latex , from which rubber i s derived , i s most O ftenwhite

,but i s sometimes red or yel low . I t i s usually thick , l ike

cream,though the solid matter contained may vary from 20 to

60 per cent .I t has never been definitely settl ed whether the rubber

exi sts as such in the latex, or whether it i s developed by theproces s of coagulation . Some latex curdles immediately andSpontaneous ly , l ike blood ; others requi re the addit ion o f

chemicals or natural fermentation , l ike animal milk. In manycases the lat ex has never been made to coagulate . I n somecases latex i s used as a b everage , whi le in others i t may behighly caustic or a deadly poi son .

A nother sub stance developed out of the latex , along withthe rubber

,i s commonly cal led res in . Some regard this as a

broken-down , oxidized , perverted or unripe” rubber. O therauthoritie s maintain the exi stence of a s erie s of res in-bearingtubes in the bark

,independent of the system of milk tubes , but

drawn out with the rubber m i lk by the same bark cuts .Rubber i s composed of two substances or “principles , one

of which , the adhesive principle , i s easi ly soluble in ether, carbon di sulphide

,and the like ; while the other, the nervy or

structural principle,i s never really dis solved . The adhesive

principle corresponds rough ly to starch , while the nervy principle corresponds to cellulose. The a dhesive principle seemsto vary directly with the res in content , without b eing qui teidentical with it . There seem s to be nothing el se in naturewhich even approximates the insoluble or nervy part of rubber. I t i s thi s which gives rubber its elasti ci ty , and enablesit to take up compound ; hence it forms the basi s of rubbervaluation . The adhesive principle , quite useful in cementsand “frictions ,” forms the basi s O f a great numb er O f “rubb erlikes , and i s of much less value .

S OURCES OF RUB B ER 9

I n the succeeding pages the leading kinds of rubber aredescrib ed and class ified according to commercial usage

,whil e

reference i s made al so to the geographical di s tribution ofrubber.

The Amazon valley, embracing hundreds of thousands ofsquare miles O f rubber-yielding forests in B razil , B olivia andP eru, i s the center O f the South American rubber industry, thewhole product formerly being exported f rom the city O f P ara ,whence the name “P ara rubber.” Several species O f the Heveaproduce this rubber, the best known being the Hevea B ras iliens is .

P eru,Bolivia and B razil also produce a rubber known as

“caucho,” and , in some markets , as “P eruvian rubber. This isthe product O f the Cas tilloa Ulei . A nother species , Cas tilloaelas tica

,i s the rubber tree of N icaragua and other Central

A merican state s , which i s al s o found in E cuador, Venezuela ,Colombia , and M exico , and yi elds the rubber known as “Centrals .

”The A tlantic states O f B razil , south of P ara , produce

other rubber trees,from which come the grades known as

“M angabeira” and M anicoba .”

“A frican rubber i s inferior to that obtained from South

A merica , but through improved proces ses in gathering andcuring, the various sorts are delivered in much better condit ion year by year . A frican rubber i s found on both the eastand west coasts and throughout the great basins of the Congoand N i ger rivers

,i n the Soudan region , and al so on the i s land

O f Madagascar. The Landolphia, which include the Carpod inus and the Clitandras

,are vines or creepers f rom which is

produced much A fri can rubber. A cons iderab le amount hasbeen gained f rom such trees as the F icus Vog elii and '

particu

larly the F unturnia elas tica,which yields “Lagos” rubber.

The E ast I ndi es to-day furnish but l i ttl e wild rubber. Thefirst rubber exported from that part of the world came fromthe F icus elas tica

,f rom A ssam ,

the name O f which provincehas attached its elf to rubber from other regions as wel l . The

i s lands of Java, Sumatra , and B orneo , al so P enang and other

states i n the M alay peninsula , and likewi se F rench I ndoChina

,produce a certain amount of rubber, mostly from vines

or creepers .Seaports , trading post s from which the firs t shipment i s

GRADES O F CRUDE RUB B ER

made , the name of a colony or country , or descriptive terms ,as “thimbles ,” “buttons ,” “s trips”— al l or any of thes e mayserve for names of diff erent grades O f crude rubber . A complete market report would indicate that there are a great number of diff erent quali ti es of rubber , many coming from thesame source . This , however, i s not whol ly true . Take

,for

i ns tance , the P ara grades : Y ears ago any rubber coming fromB razi l was cal led P ara rubber. Later i t was divided into“fine ,” “medium , and “coarse .” Then the rubber from thei s lands in the lower Amazon became known as I s lands rubber,” whi le that coming from further up s tream was knownas “Upriver, and these, too, were divided into fine, medium,

and coarse . Now a dozen or more local names are appliedto rubber from diff erent localiti es , tributary to the P ara market . A t the same time

,most of these rubbers sel l at the same

figures , grade for grade , with the exception of coarse .Something like thi s i s true in the A frican rubber trade .

F or instance , a great number O f local names are applied tothe Congo rubber. The diff erence between “E quateur,” “

Kas

sa i , and “Lopori sorts may not be greater than between

diff erent lots from the same place . W ith a very few exceptions , the names which fol low are those used commonly inthe leading markets of the world :

P ARA RUBBER.

RUB B ER is classified at P ara and Manaos into three grades ,designated by the P ortuguese words fina, entrefina,

and sernamby .

These grades in the United States are known "as “fine ,“medium ,

” and “coarse , whi le in E ngland they are class ifiedas “fine ,” “

entrefine ,” and .

“negroheads , the latte r beingdivided to provide for a subgrade , “scrappy negroheads . The

proport ion of these grades exported through P ara has beenabout 61 per cent . of fine

,11 per cent . of medium , and 28 per

cent . of coarse .F I NE P ARA rubber comes in large bottles or balls and ,

when cut, shows a surface closely marked with l ines corresponding to the number of layers of rubber milk added duringthe smoking proces s . These layers are easi ly separated and ,when stretched , are very transparent . This rubber smel lsnot unl ike smoked bacon .

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12 GRADES OF CRUDE RUB B ER

comes from P eru and B olivia through the large stream s 1 15nin those countrie s— such rivers are the P urus , Jurua , Javary ,and M adeira . Th l S rubber comes to market in b i scui t s andba l l s varying greatly in S iz e and shape , a ful l average b i scui tweigh ing about thirty pounds . The diff erence in price b etween Upriver and I slands rubber i s due chiefly to the factthat the former, being derived from more remote localities ,Shrinks les s after arriving in market . Upriver rubber i s marketed also under such local names as M anaos ,” “

M adeira,

”

B ol ivian ,” “P urus ,” etc .

MANAOS rubber is named and exported from the city whichi s the capi tal of Amazonas , miles up the Amazon riverand the center of the rubber trade of the di s trict .

MADE IRA rubber, named f rom a great river which j oins theAmazon below M anaos , i s of excel lent qual ity and producedin large quanti ti es . I t has a finer and closer grain than anyother Upriver rubber except the B olivian .

P URUS rubber comes down the river P urus , the largest ofthe rubber-yi elding tributaries O f the Amazon , and is probablythe choicest of al l the P ara grades . A certain amount of theoutput of the P urus comes from a region formerly belongingto B ol ivia , from which it was marketed as “B olivian” rubber.That region has been acqui red by B razi l and organized intothe F ederal territory of the A cre

,which continues to produce

a large amount Of rubber .B OLIVI AN rubber is floated down the Beni and other rivers

i n B olivia to the M edeira , and thence to the A mazon . I t

formerly met innumerab le detenti ons from the cataracts in theupper M adeira

,on account of which it became somewhat dri ed

before reaching market . I t has the advantage of being curedby a better clas s of labor than i s common in B raz il , of havinga tougher fiber and of being cl eaner than most Upriver rubber,for which reasons it brings higher prices than any other.

Not all the rubber of the P ara grades now comes downthe Amazon . A certain amount of the B ol ivi an output i sShipped overland to the P acific

,and some by river to southern

A tlantic port s .

P A RA RUB B ER 13

P ERUVI AN rubber, in ball and slab , was formerly applied ,in the E ngl i sh trade particularly , to the clas s of rubber whichwill b e described under the heading “caucho .” I n recentyears

,however, P eru has suppli ed cons iderab le rubber of the

same character as P ara— being derived from the Hevea. Thisrubber i s exported from I qui tos down the A mazon , most ofi t going to Europe , where it i s sold as P eruvian fine andnegroheads (coarse) , as well as ball and S lab , and al so “P eruvian weak .” TO a large extent P eruvian fine rubber loses it sidentity between I quitos and the consuming markets , and isclas sed merely as P ara .

MOLLENDO rubber comes from southern Bolivia , being transported by steamers acros s Lake Tit icaca and by rai l to Mol

l endo , a P eruvian port on the P acific , and thence principallyto E ngland . I t i s prepared in b iscui t s and sheets and i s marketed at a price between U'priver and I s lands .

A NGOSTURA rubber comes down the O rinoco in Venezuela ,from Cuidad B olivar, which town formerly was known asA ngostura . I t i s of the same grades as the P ara sorts . SomeO f the same clas s of rubber finds it s way into B razi l , atM anaos , where its identi ty i s los t

O RI NOCO rubber i s the same as A ngostura .MATTO GROSSO rubber is from the state of that name in the

southwest O f B raz il , and reaches the market partly throughtributaries of the Amazon and part ly through the P arana,

which discharges into the river La P lata . I t comes in “fine ,”“medium ,

” and “coarse ,” but principally the latter, l ittl e of i treaching the market at present .CAUCHO , which figures in all the markets of the Amazon

region , and in s tatist ics of P ara rubber general ly , i s a di stinctsort O f rubber, in ferior to P ara , collected from the Cas tilloa Ulei .It i s not cured by smoking but by admixture with the mi lk oflime , potash or soap . The physical characteristics O f caucho, in themain

,are the same as the Central American rubbers . The

rubber of thi s sort exported by way of the Amazon formerlywas obtained principal ly from P eru,

but i t has now been discovered throughout mos t of the rubber-producing regions ofB raz i l and B olivia as wel l . Caucho figures very largely in the

14 GRADES O F CRUDE RUB B ER

P ara rubber trade . I t comes to the market in three forms“bal l ,” “strip ,” and sheet” (or s lab s )—rang 1ng In value in theorder named .Caucho i s the Spanish word for india rubber in general .

When this particular sort of rubber first began to be marketed,i t was obtained only in Spanish-speaking regions

,and on com

ing down to P ara, where the commercial language is P ortuguese, and being rubber of a di stinct type , i t not unnatural lybecame known commercially by the Spani sh name

,wh ich

real ly was a most convenient form of describ ing it , so as toavoid confusion in the trade . The commercial designation ofrubber in P ortuguese, in use at P ara , i s borracha.

CENTRAL RUBBERS .

CENTRAL A MERI CAN rubber, or “Centrals,includes that

which i s p roduced in al l the states north of the Amazonvalley , up to and including southern M exico . I t forms a di stinctive class , being the product of a tree (the Cas tilloa elas tica)not native elsewhere . I n the United S tates the consumptionof Central s was once larger than that of P ara rubber, but theyield has declined gradual ly to small proportions . Thi s rubber i s in good demand for certain uses , ranking in price belowcoarse P ara . I t has not the toughness or strength of fineP ara, and possesses less elasticity. Centrals are classed usuallyas “ sheet” and “ scrap

,

” besides which the terms “ strip ,“s lab ,” “ball ,” and “sausage” are used . Greytown being acommon shipping-point for Central s

,there i s much confus ion ,

one sort often getting sub stituted for another. M ost of theyi eld of Costa R ica i s exported through N icaragua . The treatment of Central s general ly cons i sts in mixing with the latexthe juice of the “amole” vine , often in a hol e in the ground ,the product being “

Sheet” rubb er . The rubb er drippingswhich adhere to the bark of the tapped trees are peeled O ffwhen dry and called “ scrap . The trade names b elow applyto the locali ty of origin , rather than distinctions in quality .

N I CARAGUA rubber includes more than the product of thatrepublic . The real N icaragua rubber i s drier, as a rule , thanother grades of Centrals . N icaragua sheet comes to market lessclean than formerly ,

'

and the scrap brings a better price . Greytown scrap is the best grade O i N icaragua rubbe r.

CENTRAL RUB B ERS 15

GUATEMALA rubber i s inferior and unequal in qual i ty. Thebest is whiti sh in co lor , and the lower grades black w ith atarry appearance . I n curing, the rubber-gatherers pour themilk upon mats to dry , afterward s pull ing off the product insheets

,pres sing them together for sh ipment .

GUAYAQUI L STRI P, f rom E cuador , 15 Imported in two grades—good and ordinary. Like the Guatemala rubber, the besthas a whiti sh appearance . The inferior sort i s porous andfilled with a fetid black liquid , which carries an almost indeliblestain .

E SMERALDA rubber, which also comes from E cuador, i sclassed as “ strip” and “sausage ,” the two grades coming tomarket in about equal quantities .COLOMB I AN i s a pressed strip rubber, dark in color, some

times showing white when cut. I t i s graded “N o . 1” and “NO .

Some O f the rubber from Colombia bears local designations ,besides varying in quality. These includeCartagena, strip rubber, dark and tough , graded No. 1

and “NO . selling at less than “Colombian . I t comes also

in thin Sheets , rough or “chewed” in appearance , and tarry orsticky . The production has decreased very much of late .

Virgin or Virgen rubber comes from Colombia in “sheet ,strip ,” and “slab .” I t i s a product of a diff erent tree (theSapium tolirnens e ) from the other “Centrals” described here .

P ANAMA rubber, like that from N icaragua , embraces a widerange O f quality. The P acific mail steamers bring together atP anama rubber f rom numerous ports , and confusion of gradesi s a result . What is marketed as P anama” comes in “sheet”and “strip .

M EX I CAN rubber i s of fai r qual ity , but i s received in constantly decreasing quantities . The grades , l isted in the order O ftheir selling value, are “ball (or scrap ) , “strip ,” and “slab .”

Tux/mm s trip comes from the M exican port of that name .Very little of i t i s received , and that not of uniform qual ity .HONDURAS STRI P is of a quality similar to the Mexican , but

i s l ittle produced .


WEST I NDI AN rubber has a good reputation for quality. I t

is not produced on the islands , but comes from Ven e zuela andCentral America , and the designation is simply a general tradename used in England .

I t is to be kept in mind that the information given thus farunder the general heading O f

“Central rubbers” relates to thenative forest supplies from the countries mentioned . The product O f the cultivated Cas tilloas is uni formly of a higher grade

,i s cleaner, and shows much less shrinkage .The grades which follow, though not entitled geographic

ally to be included as “Centrals ,” are in fact so classed , onaccount O f their qual ity.

MANGABEI RA rubber, from the Hancornia Speciosa, i s '

so

called from the local name of the tre e producing it,in some of

the A tlantic states O f B razil , south of P ara . I t i s an alum- curedrubber and comes in sheets o f a tawny red color, which resemblesl ices O f l iver. The thin sheet sells for more than the thick , asit is drier and better cured . O ccasionally it comes in the formof balls . It i s exported from P ernambuco

,B ahia , and other

points on the coast.P ERN AMBUCO is another name for Mangabeira rubber ,derived from the principal state and port from which it i s

shipped .SANTOS rubber, f rom another port, is also Mangabei ra .CEARA .—Ceara rubber comes from a small tree particularly

abundant in the B razil ian state O f Ceara , known as the M ah ikot

Glaziovii and the M ah ikot dichotoma. The milk exudes f rom thetree and coagulates in the form O f

“tears ,” which are gathered inscraps and balls . O f late years the rubber of the region referredto has received much attention and the output has been greatlyincreased . It has come to be known more generally by the localname O f the tree, “Manicoba , O f which there are now recognized to be several distinct species . O ne O f these, the dichotoma,

yields a superior qual ity of rubber , which is marketed as“Jequi e” and “

Remanso , these being local i ty names . I t i sal so known as mul e gum .

GUAYULE is a Mexican rubber o f a relatively new type whichhas come into use to a very large extent . This rubber is obtainedfrom a shrub pecul iar to the arid regions of northern Mexico

A F RI CAN RUB B ERS 17

and southern Texas —being practically the only rubber found inthe United States . I t diff ers f rom most rubber-producing plantsin that I t has no latex , the rubber beIng chiefly 111 the cells o f thebark, a little in the wood , and none at all in the new shoots orleaves . The bark also contains balsam—l ike resins which areextracted with the rubber and are the cause of its softness andstickiness as compared with fine P ara , for example . Generallythe extraction O f the rubber resolves itsel f into two processes :one purely mechanical and the other partly mechanical and partlychemical . Botanically the plant f rom which Guayule rubbe r isObtained is known as P arthenium argentatum. Guayule is alsoknown as P ickeum gum.

A FRICAN RUBBERS .

A F RI CAN rubbers , as a class , are more adhesive and lesselastic than P ara rubbers , ranking with or below P ara negroheads . They oft en contain a l ib eral percentage of impuri tie s ,and for a long time their di sagreeable O dor and intractabl enature hindered thei r introduction . B ut advancing prices forP ara grades and fear of their coming scarcity led manufac

turers to experiment with A frican rubbers , unti l many us eswere found for them . The resul t was a notab le off s et to thegeneral upward tendency in price of the P ara grades , althoughthere are many purposes for which A fricans never have beenconsidered as competing with them . A t the same time , thepos sibi l iti es in the way of uti l iz ing A frican sorts have notbeen exhausted , each year bringing out new uses . B esides ,more intell igent supervis ion of the work of preparing rubberin A frica has led to a great improvement in some grades , ascompared with the condition in which formerly they came tomarket .

The A frican rubbers are Obtained from giant creepers , O fwhich there i s a score or more spec ies on the continent and inthe is land of M adagascar

,and also from several trees , the most

important one of which,di scovered first in the Gold Coas t

Colony , i s known now to be widely di s tributed . There i s nowalso a considerab le production of “root rubber,” Obtained fromunderground creepers and marketed as “

Lower Congo thimbles ,” and also as “B enguela ,” according to the sources of producti on . The adul teration O f A frican rubbers i s not uncom


mon,being due to the di shonesty , not only of nat ive gatherers ,

but doub tless als o of some foreign traders on the coasts . B ut

in most of the European colonies in A fri ca stringent regulations have been adopted to prevent such adulterations . O n

the Gold Coast the lumps O f rubber brought to market bythe natives were formerly cut

"

(into strips or buttons by

machinery,before being exported . Latterly some of thi s work

has been done in E ngland , the rubber then being known asLiverpool pressed .”A s a rul e, A frican rubbers are obtained by the destruction

of the trees or vines with the result that the total receipts fromthat continent are decreasing , despite higher prices than prevail ed formerly .

B ALL is the class ification of a large Share of the A fricanrubbers , which comes in every S iz e from three or four inch esin diameter down to half an inch or les s . Small bal l” of theseveral kinds di ff ers from the

“ large bal l in S ize , and i s al sodried and affords a smaller degree of shrinkage .

TH IM B LEs .— The natives , after gathering thi s rubber , cut

it i nto cubes,about an inch square or l es s . Thimbles gen

erally contain bark and sand , but very litt l e moisture .NUTS — Rubber thimbles from A mbriz are quoted some

times in European markets as “Ambriz nuts .”LUMP rubber comes in large pi eces

,varying in s ize and

of irregular Shapes . When packed in casks the pieces O ftenbecome massed together in transit . I t i s from the best of thelump rubber that the most desi rable button s and strips aremade .

F LAKE comes in lumps , l ivers , and soft i rregular masses ,and is valuable in the factory chiefly for frictions and for softening compounds .

P ASTE i s the same as flake . The A ccra flake and N iger 'paste , which are the same in qual i ty , are at the foot of thelist, in respect to prices , the N iger be ing the cleaner.

STRI PS are lump rubber that i s S l iced and pressed bymachinery before it i s off ered to the trade .


S I ERRA LEO N E .

S I ERRA LEONE TW I STs (No . 1, No . 2,and rej ecti ons ) .

This is white and amber in color,of low shrinkage

,and has

bark and gri t in i t , but l ittl e moi sture .N IGGERS (No . 1

,N o . 2, NO . 3 ) are qui te moist . NO . 2 and

NO . 3 contain considerab l e soi lCAKE— F airly clean ; but wet . I t i s both red and white

,the former br inging the better price.

MAN OH TWI STS .—This comes in the shape of tightly

wound cords of rubber and works soft . I n color i t is b lack orwhite, the b lack being the better.

LI BERIA.LI BERIAN .

—Thi s i s graded as Lump,Hard F lake

,and

Soft . I t cuts yel low , i s v ery wet , and i s often a soft pastyrubben

ASS I NEE .

What is known as A ssinee i s graded as follows : A ss ineeS ilky , Grand B assam,

A ttoaboa, Lahou, B ay in, Half Jack. It islike O ld Calabar, only i t comes in chunks three inches square ,is wet , and cuts yel low . These names are chiefly used in theEngl i sh market .

GOLD COAST COLON Y.GOLD COAST.

—Thi s i s chiefly lump from which S trips andB uttons are made . There are al so B i scuits and N iggers (hardand soft ) . The F lake i s wet and has a bad smel l , but otherwi se i s quit e clean .

A CCRA —The A ccra lump furni shes S trips and B uttonsand i s graded “prime,” “s econds ,” and “thi rds .” The lowergrades are F lake and P aste .CAPE COAST.

—This i s another lump from which S tripsand B uttons are manufactured and has for lower grades F lakeand Soft:

SALT P OND.—This Lump is also used in Strips and B ut

tons , the lowest g rade being F lake .A DDAH N IGGERS (graded as No . 1 and No . 2 ) i s very sim

ilar to S i erra Leone , but general ly in small er bal ls . I t i s not


an A ccra rubber, nor are Quittah Nigg ers or A xim. A s a matterO f fact , the grades from these diff erent ports vary l it tl e i fany , and are sold most frequently under the head of “A ccra”rubber, from the name of the principal town in the colony .

TOGOLA ND.

LOM I (or LOME ) BALL— The best grade O f this is a clean ,firm rubber and is fairly dry . The lower grades are rare ly seen .N I GERI A (I N CLUDI NG LAGO S )

LA Gos .—This lump is also turned into Buttons and S trips ,

while soft in ferior lumps are Sold as low grades without manufacturing . I t i s very easily distingu ishable from A ccra by itsOdor.

N I GER— The chief grade is P aste , which has an acid smelland is a low grade pasty rubber, wet but clean .

O LD CALABAR.— I t i s graded as B lue, Lump,

and N iggers ,and is very bad smelling. The best lump is undoubtedly used forstrips and buttons .

BEN I N BALL— I S generally dirty and has a rotten, woodysmell .

CAMEROON S .

CAMEROON S .—The ball is graded as large, mixed , and small ;

the clusters , which contain some fi fty balls , as NO . 1 and NO . 2 ;

and the knuckly ball , which I s a small dry ball . This rubber hasa fairly strong smell .

B ATANGA B ALL B ,

” —Same as Cameroons , B atangabeing the name of a river and country in the Cameroons .

F RENCH CONGO .

F REN CH CON GO RUBBER is very similar to Cameroons , butthe balls are larger.

GABOO N i s the best known flake and has for additionalgrades : lump , large “O” ball , and small “O ” bal l . The flake i sfree from dirt and is soft .

MAYUMBA is both ball and flake . A nother grade known asM ixed is a combination O f the two and is sold as second quality .

LOANGO .—Ball .

These are names of rubber stations on the coast. The nativesboil rubber milk , adding the juices O f vines , and , while the rubber


is hardening, wind it into balls , weighing from one-fifth pound tothree pounds . The best rubber is not boiled,the milk drying on

the wrists O f the natives , as they tap the rubber vines . A t thecoast the balls are cut, to detect any cheating, and washed andpacked in casks for export .

BELGI AN CO NGO (F ORMERLY CONGO F REE STATE ) .

CONGO rubber comes in the shape O f buttons , balls (NO . 1

and NO . red thimbles , and black thimbles . The ball is s imilar to Cameroons , but tougher. The Dutch Congo ball is thesame as the Congo ball , but is known as the best grade O f thatrubber. There is al so the Congo (Kassai ) , black twist (gradedas fine

,mixed

,and secondary ) , and red twist . The strips are

among the toughest O f A f rican rubbers and are dry, with a woodysmell .

F rom the Lower Congo comes also the Luvituku,which is a

red ball rubber, and from the Upper Congo , the following :UPPER CO NGO — Ball , red ball , twists , and strips , all of which

are good tough rubber.UELE .

— S trips , usually heated and fermented and badsmell ing ; cakes , wet , but clean .

SAN KURU .— B all , very similar to Congo ball .LAKE LEOPOLD.

— Graded as sausage and ball . I t does notdiff er from the foregoing enough to warrant special description .

EQUATEUR .— In the form of balls (small and mixed ) . I t i s

dark, d ry , and clean , but contains some fermenied rubber, whichsmells badly.LOPORI .

— Graded as ball (large and small ) , strips , andcakes. Some of the balls are fine and clean , while others contain

fermented milk . Lopori also comes as sausage .B ANGUI .

—Comes in the form O f strips, firm and tough .B USS I RA .

—Ball ; a trifle softer than Lopori , but usually o fexcellent quality and dry. In use it develops a strong smell .A RUW I M I .

—B all . This usually comes as large , firm balls .When Opened much O f the interior is found fermented .


MONGALLA. - In this the ball is s imilar to Upper Congo redball . I t also comes in strips

,and is a good rubber.

Some other designations o f Upper Congo are Kassai,

Katanga, Ikelemba, Loango, I sanga, and SO on .B UMBA. —Ball ; B uki . —B all ; Tat/a and Kwilu are all good

Upper Congo grades that are not distinctive enough to dwellupon .WAMBA .—This is a grade of thimbles and is a good black

rubber, with only ordinary shrinkage .ANGOLA.

BENGUELA .—Graded as sausage and niggers . O f the latter

,

NO . l i s clean and tough , and NO . 2 contains a large percentageO f red lea f .

MOSSAMEDES is practically the same, f rom a neighboring

LOANDA . - I h this the grades , which are sausage and niggers , are similar to B enguela, but not so dry . There are alsotwists (red and black ) .

A M B RI z.—Chiefly thimbles or nuts ; both are poor grades .

EAST AF RI CA .UGANDA rubber comes f rom B ritish East A f rica . I t i s pre

pared in sheet form under modern methods , and arrives in goodcondition .

M OZAMBIQUE rubber is that coming from the port O f Moz

ambique, f rom other ports in P ortuguese E ast A frica , and perhaps from still other places in E ast A frica . I t possesses someproperties in common with the M adagascar rubbers . The rateO f shrinkage is less than In most A frican sorts , and good pricesare Obtained . In the Liverpool market, which is the best forMozambique grades , quotations are made for orange ball N O . 1,

ball NO . 2 , ball NO . 3 , liver, sausage , root , sticks or spindles ,sticks removed , unripe .

O rang e B all (resembling an orange in size and shape ) i s thechoicest rubber. O ther grades of Mozambique ball are distinguished further as “white” and “ red ,” the latter being inferior.I ts reddish color is due to the fine bark mixed with it . The nu

ripe contains more bark than rubber, and is not thoroughly cured .


S ticks or spindles consist o f spindle- shaped pieces made O fslender strings O f rubber wound around a bit O f wood . Liver(or cakes ) is in smooth pieces O f i rregular size .

LA MU ball , l iver, sausage , and root come from the Mozam

bique port of that name . They are not rubbers of a distinctivesort.

MADAGASCAR.

MADAGASCAR rubber formerly ranked higher in price thanmost other A frican sort s , though to-day the highest price i sO btained for some O f the Congo sorts . Considering the greaterloss sustained in washing, i t cost s nearly as much at timesas fine P ara . I t i s a favorite with manufacturers of hardrubber, on account of the fine lustrous poli sh which i t assumesunder the buffing wheel. The principal classification i s between P inky and B lack .

P inky comes in round balls, weighing to 4 pounds , blackon the outs ide from exposure to the air, but having a pinki sh-white look when cut.

B lack, also in small balls , when cut shows a dark color, andi s more or les s sandy and dirty .

TAMATAVE b eing the principal seaport , it s name i s l iab le tobe appli ed to any grades shipped from there . B ut what i sdescribed as “P rime pinky Tamatave” i s the best M adagascarrubber .

MAJUNGA rubber , from the W est Coast town of thatname

,i s a dark rubber of special excel l ence , ranking next to

P inky in price .N iggers (or negroheads ) are designated as East Coast and

W es t Coast,” and al so as “red ball ,” and gri st ly .” Theygenerally contain sand and dirt .

B rown cure (or brown slab ) i s a still lower grade .Unripe i s the lowest . This term is applied to balls contain

ing bark in the center.Rubber from M adagascar i s sold at F rench auctions also

as “Lomb iro,

” the native name of a newly found plant ,“Morondava ,” “

B arabarja”

(names of locali ti es ) , and SO on .M adagascar rubber i s cured (1) by the use of salt water ,in which case the water i s n ever whol ly expel led , leading to

EA ST INDIAN RUB B ER 25

a heavy rate of shrinkage , and (2 ) by artificial heat . The

i s land i s ri ch in rubber forests , but the export s are restri ctedby the wasteful methods of the nat ives

,which exhaust the

trees and vines,particularly near the coast .EA ST INDI AN RUBBER.

A SSAM rubber, the product of the F icus elas tica, 15 strongand O f firm texture . I t i s fairly elast ic , though O ften less soon account of careles snes s in gathering and the introduct ionO f impurit ie s . There are four grades usually (No. 1 to NO .

of which the lower ones are extremely di rty and contain softrubber . The bett er grades when cut have a glossy , marbleizedappearance

,somewhat pinki sh in color. A s sam rubber i s

marketed in small ball s , made by winding up strings of rubberdried on the trees,and al so in oblong slab s of irregular s ize ,

wrapped in plaited straw . The output has decl ined for several years . M eanwhi le the same Species has been found inB urma , where the production of rubber has increased , thoughthe whole output of fores t rubber from B rit i sh I ndia i s nowsmaller than at an earl i er period .

RANGOON rubber i s the product of B urma , export edthrough the port of Rangoon , and diff ers so l ittle from A s samrubber as to require no s eparate description . F our grades aremarketed , at practically the same prices as for A s sam rubber.JAVA rubber , from the island of thi s name , i s dark and

glos sy , of a deeper tint than the A s sam sort s , with occasionalred streaks . O therwis e , i t s hi story and characteri stics arenearly identi cal with those of A s sam rubber. Three gradesare recogniz ed . The milk dries on the surface of the trees ,on exposure to the air

,and the shrinkage O f the better grades

i s s l ight .JELUTONG.

—See P ontianak .P ENANG rubber (from one O f the states in the M alay

peninsula , including the i s land of P enang) i s al so very similarto that from A s sam . There are three or four grades , at sli ghtlylower prices than the A s sam sorts bring.

B ORNEO rubber ranks below the other A siati c sort s , beinglower in price

,with a higher rate of shrinkage . I t i s O f a

whiti sh color , changing with age to a dul l pink or red . I t


comes to market shaped like pieces of liver,and i s soft

,porous ,

or spongy . The pores are fi l led with salt water or whey,for

the reason that salt i s used to coagulate the rubber, and thewater evaporating leaves a sal ine incrustation in the cell s .There are three grades

,the first of which i s a good rubber,

while the lowest, when cut, i s almost a s soft as putty , and i sworth l ittle .

P ONTI ANAK, also known as j elutong, gutta j elutong, Gambria , besk and fluvia, i s a low-grade rubber, chiefly from B orneo .

I t i s the product of the latex of the Dyera cos tulata, and asgathered by the natives is doped with kerosene and earthy matters , still further lowering its value . The gum was formerlyclassed with low grade guttas , as it was O ften used by the Chinese to adulterate the high grade guttas . I t i s , however, not agutta but a very resinous rubber. The rubber content is about10 per cent . and when crude rubber was high it was extractedat a profit and hundreds of tons o f it used .

There are several grades , as P al embang, P ontianak , Sarawak, B andj ermassin , etc ., the names being taken from the districts in which the gums are gathered .

P RE SSED OR RE F I N ED P ONTI ANAK in its naming indicatessil fficiently its characteristics . I t contains less of the usual impurities , has no Odor O f kerosene , and on washing and dryingloses from 40 to 50 per cent . I t brings 6 or 7 cents a pound morethan the ordinary grades .

GUTTA-P ERCHA . -See Chapter X ’

X . The highest grades ,of which there are several , are well typified in what i s knownas red M acas sar , which brings a pound , as comparedwith the low grades at 19 and 24 cents . The fol lowing arelow grade guttas :

GUTTA-S I AK (A lso called book gutta .)— This is a lowgrade gutta sometimes mixed with j elutong. I t is prepared atS iak in Sumatra and its port of shipment is S ingapore . I ts

regular form is a square folded sheet, or “book with roundededges

,made by laying a sheet O f the softened material in a series

of folds,meeting in the center. The final end folds , at right

angles to the first,producing the round-edge square book .

Cold gutta- s iak cuts tough , gummy and wet and may becracked or split O ff by a light blow. The f racture shows a closely


000 tons . The leading factor underlying thi s rapid growth 15the extensive use O f rubber for motor-vehicle ti res . The extrarubb’er came almost wholly from plantations .

P roduction O f P lantation P ara rubber is also establishedon a sci entific bas i s . Every phase of it s cultivat ion and production proceeds under the close s tudy and careful ly plannedexperiments of government and plantation association experts .The measures have practically attained the economical production of standard P ara grades capab le O f supplanting thebest wi ld P ara for e ssential ly every purpose .

The prediction was made in 1909 ,by the planting interest s

of the F ar East, that when the Hevea trees then plantedshould reach tapab le S ize , Ceylon and M alaya would aloneproduce as much rubber as at that date entered into theworld’s total consumption . Th i s resul t was attained in 1914.

The growth by years i s interesting.Year P ounds Year P ounds Year P ounds

1903 1908 19131904 1909 19141905 1910 19151906 1911 . 19161907 1912 1917 est.)

A ny fear O f overproduction O f rubbe r, through the cominginto bearing o f so many planted trees , i s O ffset by the fact thatthus far the sources O f wild or forest rubber, with the sole exception O f the native H evea (P ara ) trees in B razil , are beingexhausted by the extraction O f their product . Where trees andvines are killed by the rubber gatherers , there may be an in

creased yield from a given country for a while , due to the working of new areas from time to time , but ultimately the principalforests are overrun

,a fter which the output falls O ff .

The cleanliness o f plantation as compared with forest rubber has been an attraction f rom the beginning, and the higherprice paid for the former has been due to its greater content,bulk for bulk, of rubber. O riginally it proved deficient instrength as compared w ith the Brazilian product . F or some purposes the deficiency O f nerve of the new rubber did not prove adisadvantage

,as

,for instance

,in solution making, in which it

has been largely used . Gradually, however, it has replaced P arain practical ly every use to which the wild gum i s put.

P LANTA TI ON RUB B ER 29

Rubber from Hevea plantations was at first clearly notidentical with the product o f the same species under forest conditions . The question was discussed as to whether this diff erence was due to the plantation rubber not being smoked

,as is

done with B razilian rubber. A reason now more generally givenis that, owing to. the tapping O f planted trees having been begunat a very early age, the product was “ immature .” A t least plantation rubber can now be had with more strength than formerly

,

which may be due either to increased age O f the trees or tobetter methods

,

o f collection , coagulation , and care in subsequentstorage and shipment .

P LANTATI ON O R P LANTATI ON P ARA is the term applied inthe trade to the new class O f rubber. “Ceylon,

” “Malaya

,

”

“Straits ,” “Java ,” and Sumatra are also applied , but these aremerely local designations

,indicating no diff erence in quality, all

being produced by cultivated Hevea. What is more importanti s the growing practice O f planters O f stamping their productwith trade-marks , by means of which buyers may know abso

lutely the source of any particular purchase, which is helpfulwhen a producer O f several tons in a year is attempting to establish a reputation for qual ity. P lantation P ara is produced invarious forms , as follows :

B is cuits - P repared by allowing the rubber milk to set inshallow receptacles , with or without acetic acid , and washing androlling the cake of rubber which appears at the top more or lessci rcular in form— usually to inch in thickness and 10to 14 inches in diameter.

Sheets .—F ormed in the same way as biscuits , but rectangu

lar in outl ine . O n account of their Shape they lend themselvesto more economic packing. B iscuits and sheets are sometimespressed together to form blocks .Crepe— This rubber, on account of the washing and tearingwhich it undergoes between the rollers o f the washing machine

used in its preparation , contains a minimum O f impurities . I t hasan i rregular surface , is uneven in thickness , and , like lace orflake rubber

,dries rapidly. O n account of the washing which

some manufacturers subj ect all rubber to , it has been questionedwhether the extra labor involved in its preparation will be paid

30 GRADES O F CRUDE RUB B ERO

for by the extra price realized . P repared in lengths of 3 to 6feet,and widths of 5 to 12 inches , and graded according to color.Worm— The product Obtained by cutting i rregular sheets

O f freshly coagulated rubber into thin worm- l ike rods,shears

or machinery being us ed . B y pass ing the dry worms throughordinary washing rol lers they are bound together into an evenstrip of crepe .

Lace— Ve ry thin perforated Sheets O f considerable lengths .I t comes from the machine in a continuous st rip

,and i s cut

into pi eces 6 feet long as it runs on to wire trays . I t i s s ometimes pres sed later into b i scui t s or sheets .

F lake— O btained by placing small pieces O f f reshly coagulated rubber in a smal l roll ing mach ine or washer,the corru

gations of which run horizontally ; the rol lers are close together and the cut rubber i s sues as thin strips .

B lock.-Made from pressing together sheets

,biscuits , or

other forms of rubber, in a freshly coagulated or partly drystate

,i n sizes usual ly 10 x 10 x 6 inches

,the chief purpose

being to reduce to a minimum the surface exposed to the ai rafter preparati on .

S crap.—The remnants Obtained after tapping, rolled into

ball s or made up into cakes . I t i s shipped with or withoutother preparation ; i t i s sometimes made into crepe . I t bringsa comparatively high price .

O f these various forms the present accepted types withthei r market names are :

F I RST LATEX CREPE — A th in , pale , and clean creped sheet ,the b est grade of P lantati on P ara .

A MBER CREPE — This comes In four grades , describ ed asgri stly b lanket .” I t i s rough

,thick , and light- colored . The

other grades are S imi lar in form but vary in color to darkamber

,frequently mottl ed in appearance .

B ROWN CREPE — A lower grade than amber crepe , varyingfrom th ick to thin sheet ; l ight to dark-brown color . E re

quently it i s specky with barky impuri ti es , requi res washing,and is easi ly torn apart in the sheet .

SMOKED SHEET, RI BBED STANDARD QUALITY .— This formhas the distinctive smoked P ara odor, varies in color from

P LANTA TI ON RUB B ER 31

l ight to dark-brown , and viewed by transmitted l ight , i s translucent . It strongly resi st s stretch ing and may be dis tendedinto a thin film exhibiting marked tensi l e s trength andstretch . The surfaces are embos sed with various des igns ofribbing sometimes

,including plantation names . These designs

serve as trade-marks for the identification of the produce fromindividual plantations .

SMOKED SHEET, P LAI N STANDARD QUALITY.—Thi s is thesame in al l respects as the “ribbed standard qual ity” exceptthat it has no ribb ing.

UN SMOKED SHEET, STANDARD QUALITY .— The same asplain smoked Sheet except unsmoked .COLOMBO SCRAP . —~M assed clear, l igh t-brown strings and

bits O f high-grade rubber, more or l es s specked with bark .CEARA plantation

,f rom M anihots

,comes from Ceylon and

Malaya , and from some German colonies in A frica .MEX I CAN plantation is very clean , not differing otherwise

in quality f rom the product o f the same tree (Cas tilloa) underforest conditions . I t comes as strips , when the latex is creamed ,coagulated, and run between rolls, and as Grena when the product is scrap-picked from the cuts on the trees and coagulatedonly by exposure to the ai r.

TRI N IDAD plantation , TOBAGO plantation , WE ST I NDI E S plantation,CENTRAL A MERI CAN plantation , GUAYAQUI L “Cas ti lloa,”

and such terms relate to the product of cultivated Ca stilloa treesin the regions indicated . A certain amount O f Cas tilloa plantation rubbe r also comes from Ceylon and Java .CONGO plantation , from various species , comes f rom B elgian

Congo (Congo F ree State ) .

UGANDA plantation comes from B ritish E ast A frica .RAMBONG i s the native name in the F ar East for the F icus

elas tica,which produces the A ssam rubber of commerce . A con

siderable amount O f cultivated Java and Ceylon F icus rubber issold under this name . This comes in crepe , sheet, and block .

CHAPTER II.

SOME LITTLE KNOWN RUB B ERS A ND B A STA RD

O R P SEUDO GUMS .

F ROM time to time reports come in from al l over the tropical world regarding the discovery oi gums , some of whichare s imilar to india rubber, while others are more like guttapercha . I n a few instances these gums have appeared on themarket

,i n due time , under various names and have been use

ful . Thi s i s not the rule , however, and i t i s due to a varietyO f reasons . The firs t is the scientific att itude of those whoprimari ly examine the samples received at the great centers ofcivi lizat ion . Unles s gums are of high grade , and bear promiseof being nearly as valuabl e as a good g rade of india rubber orgutta-percha , they are usually pronounced worthless , or nearlyso . N evertheless , rubber manufacturers are ever in the marketfor these product s , and would welcome many of the pseudogums and find large us es for them , i f once they were withinreach .

A s ide from the scientific atti tude i s the indifference of thegatherers in their native wi lds , of the importers who see littleprofit in such cheap gums , and of the manufacturers themselves , who wait unti l a neighbor has tried something new before venturing to experiment .

O ne has only to recal l what i s needed in rubber compounding to see how valuable many of these gums could, bemade . F or example

,sometimes s imple stickines s i s cal led for,

in another cas e only insulating qualiti e s and stickines s , inst i ll another, water-proofing qual i ti es and stickiness , and, i ti s well to add here

,where only one valuable quali ty exi sts in

a gum others can O ften be supplied . A S a matter of fact , inthe present stat e of compounding and manipulation

,the pres

ence of res ins i s not heeded , short l ife can be overcome, andintractabi l ity can b e done away with .

32

A B B A RUB B ER— ALME IDINA 33

I t i s with the hope that some of the gums mentioned inthe following pages may be useful in rubber manufacture thatspace has been given to them .

A BBA RUBBER—Thi s i s from Lagos, probably the productof the F icus Vog elii . I t i s low grade , cures soft and short ,and contains a large percentage of res in . The trees are most

abundant in Grand B as sam , and grow rapidly to great s ize ,s ingle trees often yie lding 10 or 12 pounds in a season . The

milk i s coagulated by adding vegetab le acids and boiling. Therubber is bright red . I t contains about 55 per cent . rubberand 45 per cent . res in , and forms 30 per cent . of the latex .The washing los s i s 10 to 14 per cent . O ne report i s that thelatex of this tree is mixed wi th that of F untuinia elas tica

,the

mixture being called by the nat ives aba-odo .”A BYSS I N IAN GUTTA .—A n adhes ive acid gum of an earthybrown color

,s imi lar to common gutta in external appearance .

Softens in water, but keeps a very great elastici ty . O n dryingi t remains exceedingly adhes ive , therefore could not b e used inplace of gutta-percha , but with proper treatment would undoubtedly make an excel lent friction gum .

A LME IDI N A . —Thi s comes from W est A frica , particularlyfrom the Cameroons and A ngola , and has been found in theSolomon I s lands . I ts source i s a shrub with succulent stems ,all of which are tapped . The milk i s boi led and the resultantball s dri ed in the sun . I t comes to market in small and sulphur- colored nodul es , resembl ing potatoes , for which reasonit sometimes has been call ed “potato gum .

” When brokenopen

,thes e ball s look l ike putty , and although quite brittle

when cold,the gum easily softens in warm water and may bedrawn out in threads , wh i ch are possessed of some elasticity .

I t i s completely melted at 240 degrees F .,and remains rather

sticky after melt ing. I t almost completely dissolves in coldbenzine ; i n fact , nearly al l of the solvents ord inarly used inrubber manufacture di ssolve it . I t mixes and dis solves withrubber in almost auv proportion and up to 25 per cent . atl east . Not onl y does i t not injure the rubber , but i s said tobe beneficial to i t . I n working on the m i l l a pungent vaporarises from the mas s

,which

,however , has no poisonous eff ect .

I n us ing thi s gum ,a l ittle caustic soda sometimes is added to

34 LI TTLE KN OWN RUB B ERS

O

the water when it i s being washed ; some manufacturers addtannic acid . A nimal or vegetable fixed oi ls do not dis solveA lmeidina, and therefore when mixed with i t are apt to rot it .M ixed with gutta-percha this gum i s practically indestructible .The name A lmeidina” i s that of the first important shipper ofthe gum ; i n E ngland the spell ing “

A lmadina” has come Intouse. The gum i s known al so as “Euphorb ia gum.

” Warburgand Jumelle say that A lmeidina comes from Euphorbia rhipsaloides

,which must not be confused with E . tirucalli. B erry gives

A lmeidina per cent . resin,and per cent . hydrocarbon .

Latex from E . lactiflua (Chili ) contains to percent . of caoutchouc and per cent . resins reckoned on thedry substance .

A MAZON IAN RESI N RUBBERS .— The valley of the Amazon

contain s various trees and plants that are caoutchouc producers , but which are general ly neglected , as the gatherers areseeking the more valuable Hevea or Cas tilloa. A t the sametime the latex of some of these plants has been referred to asbeing used to a considerab le eXtent for adulterat ing P ara rubber. Among these are mentioned the trees known under thenative names of Amapa

,Sucuba , Surva , Tamanguiro ,

M ol

ango,etc . A ll of these Show a marked percentage of resin

in the milk .A NTI POLO GUM is being made from A rtocarpus incisa (thebreadfrui t tree ) in the P hi lippines . A ntipolo i s a town in the

province of Luzon .B AKA GUM —F ound in the F ij i archipelago . Comes from

F icus obligua (F oret) . Used by natives for birdlime . M ilk veryabundant . Gum l itt le known . Samples sent to E ngland werereported upon as being sui tab le for mixing .

B ANAN A RUBBER—Green bananas yi eld considerab le latex ,which is per cent . water and only per cent . rubber. ’

I t i s easily coagulated by boiling. M ade from M usa sapientumand M . paradis iaca.

B ARTA- B ALLI .—O ne of the best known native trees in the

Guianas . The m i lk of th i s tree i s sometimes mixed withB alata m i lk and i s said to give it its reddi sh tint . The gumwhen dried b y evaporation i s rather sticky and soft , but when


M exico,and also in portions of Central A mer i ca . Chicle

should be of a whiti sh color, odorles s , and free from impurit ies

,but O ften is adul terated with an inferior pink or reddish

soi l . I t 1s solid and britt le at ordinary temperatures , but becomes plas tic when placed ln hot water. I t i s qui te soft at49 degrees C . (120 degrees I t i s us ed chiefly in theUnited S tates in the manufacture of chewing gums , and to asmal l extent i n E ngland for adhes ive plasters . I t has b eenus ed for modeling purposes and for mixture wi th india rubberfor insulat ion work . The frui t i s about as large as an apple

,

though looking more l ike a quince and i s eaten under thename of “sapodi lla” or “ sapoti l la” plum . The frui t i s prickedor s liced and the latex is al lowed to ooze out without squeezing

,so as not to get the other juices . Lateral tapping i s used

on the tree , and 15 to 25 pounds of milk or 5 or 6 pounds ofgum may be Obtained in one s eason without injuring thetree . The milk i s coagulated by boi l ing. P rolonged boi l ingmakes i t reddish , though some trees are said to yield a redgum . Th e best chicl e i s made from highland grown trees .The trees sometimes grow 70 feet high , and the wood , whichi s very heavy , takes a high poli sh and i s qui te valuab le . The

analysi s of chicle shows per cent . res in,

per cent .rubber

,9 per cent . water, and per cent . s tarch and other

matters , on an average . I t sometimes contains as much as55 per cent . of res ins , when dry .Chicle i s 60 per cent . soluble in acetone ; the remainder

can be powdered and has none of the characteris tics of rubber .COORON GITE .

-Sometimes known as A ustral ian caoutchouc .A n indiarubber—l ike material

,discovered first near Salt creek ,

a short '

d ista'

nce from the coast of South A ustralia . I t wasfirs t ob served in l ittle hollows of sand and resembled patchesof dried leather , but i t general ly occurs in the swamps . I t i ssupposed to be of the petroleum series . Some sci entificauthori t ies in E ngland and America ascribe to i t a vegetab leor igin and regard the gum as exuding from a plant or l ichen .I t is not soluble in the ordinary rubber solvents

,but after mix

ing with india rubber it can be dissolved . A ccording to F orster,it vulcanizes somewhat as india rubber does .

COW TREE RUB B ER—GUTTA -SHEA 37

Cow TREE RUBBER—The cow tree i s very plentiful i ntropical South A merica and yields a milk commonly us ed forfood . This milk contains considerab le caoutchouc , which isabout 30 per cent . resin . B otanically it is known as the B ras imum galactodendron. Besides B ros imum galactodendron, War

burg mentions another cow tree, Couma utilis , an Apocynacece,g rowmg In northern B razil, while B . galactodendron is an A rto

carpece of Venezuela. Couma uti lis latex contains rubber, andis used by the natives in waterproofing. Cow tree milk is exceedingly hard to coagu late, and evaporation product is completely soluble in hot acetone, seeming to indicate absence of anyrubber. The constituents are mainly fatty matter, possessingneither tenacity nor elasticity, according to the Germ an chemists .CUMA I RUBBER— F rom the mi lk of a tree found on the

Rio Negro and Uaupes , in B razi l . None comes to market .Thi s milk i s used by the nat ives for waterproofing purposes .

GOA GUM .—Thi s ’ i s a gum that comes from the M ivalcantem

,wh ich grows wild in the Concan di strict in B razil ,

and is al so planted for hedges . Chocolate in color,softens

under heat,i s eas ily molded , and thoroughly wate rproof .

GUTTA-BASS I A .—F ound between Upper S enegal and theN i l e . Has the appearance and apparently many of the properties O f gutta-percha . Soften s in warm water and becomesglutinous at the boil ing point . I s s olub le in sulphide of carbon

,chloroform

,benzole , and alcohol . Can be kneaded in

water as eas i ly as ordinary gutta . I t may be the same asKarite gutta, which is from B ass ia P arkii

,though there are

other A frican B assia s which are said to yield good gutta .GUTTA-GREK .

— A gum that comes from P alembang, inStrai ts S ettlements . I t appears very much l ike india rubberbut i s permanently softened and destroyed by heat sufficientto melt i t . I t smell s like gutta-percha rather than indiarubben

GUTTA-HORFOOT.—This is a vegetable juice sent in sealed

tins from the S trait s S ettlements , which yields a material l ikeindia rubber of fai r qual ity . NO way of coagulat ing the juice ,where it i s gathered

,s eems to b e known .

GUTTA-SHEA . —Said to b e the nearest approach to gutta~percha among A frican products ; O btained from the Shea ,


Galam,or B ambouk rubber- tree (B uty rois‘permum P arkn ) . The

butter i s the s ol id fat contained in the seeds and i s used inmaking hard soaps . Gutta- Shea i s s eparated from the fat inthe cours e of the soap making and i s found to be present tothe extent of from 5 to 75 per cent . A kind of gutta-perchais al so obtained from the trunk of the tree In small quantiti es .A l so known as “Karite gum .

”A nalysi s of the butter shows

guttalike per cent . ; res in per cent . ; water 5 .04 percent . ; impuriti es per cent . The yellowish butter smel lsand tastes much l ike cocoa butter. Cazalbo claimed to havediff erentiated two varieties , one yielding a red and the othera yel lowish gum . The red kind i s the more valuab le

,and

this tree also yields gum from its trunk, while the yel low gumtree does not . I t i s uncertain whether the yel low butter yieldsany gutta , though the trunk gutta from the other vari ety i scomparab le to Red B orneo in toughnes s and in its structure .Called also “

Karite gutta” and “Shea butter.” Knowledge

on thi s subj ect i s s t i l l confus ed and the authorit ies confl ict .The two varieties are cal led “

Shea” and “M ana ,” the Shea

being the one which yields gutta , and also the more abundantvariety . The branches seem to yi eld even more than the trunk .The milk i s al lowed to stand in the open ai r ” for about 24hours , when it partial ly curdles . The crys tall ine particle s arethen kneaded into a mass in hot water. However, reports onthi s gum are confl icting, and it i s probab le that two sourcesare confused . Some advices seem to point to the plum- l ikefrui t as the source of both gutta and butter. F endler andH eim consider Karite gutta worthles s as a substitut e forgutta-percha . I

GUTTA-SUSU OR B ORN EO No. 3 .— A lso called gutta grip ,

at S ingapore , and formerly known as “A s sam white . The

washing los s i s 30 to 45 per cent ,and the clean rubber con

tains per cent . res in . In Java and Sumatra it i s general lystored under water . The vine i s tapped and the gum l eft todry on the bark . The milk i s sometimes gathered and coagulated with sal t and boi l ing, but thi s method i s not so goodas bark drying. I t i s white and remains so under water, butdarkens on exposure to the air.

INDIAN HEM P RUB B ER—MUDAR GUM 39

I NDI AN HEMP RUBBER (Apocynum) .— Coagulation of latex

i s spontaneous , yie lding about 33 per cent . of coagulum , containing 4 per cent. O f low-grade, black, so ft rubber.JELUTONG.

—See P ontianak .JEVE

,JEBE

,OR HEVE (hence Hevea ) was the ancient namefor rubber among the natives of E cuador . The name was appli ed to a rubber coming principal ly from the neighborhood

of I qui tos , P eru. (See P eruvian rubber .)JI NTAWA N .

-A bastard gutta-percha mentioned byThomas Hancock in four patents and also by Taylor and Duncan . P robab ly a mis- spel ling of “Dj intaan soesoa,

” the sameas gutta-susu.

LORANTHUS RUBBER.-A s ticky non- eflastic Venezuelan

product . Contains 18 per cent . of res in .MABOA GUM .

— Sald to be produced from a species ofF icus in Santiago de Cuba .

MA CWARRI E B A LLI GUM .— A rubber gathered in B riti sh

Guiana f rom the F ors teronia g racilis . F rom the report of thedirector of the Kew gardens , to whom a sample was submitted , i t would s eem that , while the gum i s at present unfitfor use in place of ordinary caoutchouc , because of it s stickines s

,i t might be of value in cements , frict ions , and the like .

F orsteronia g racilis is a vine or bush rOpe belonging to theA pocynacece. The milk appears to be often mixed with thatof balata or B artaballi

,though M acwarr ieballi i s more like

rubber than balata . The vine i s very rich in latex.MA NGEGATU GUM .

—Thi s comes from V i zagapatam , I ndia ,and i s a gum of the bastard gutta type , S imi lar to gutta trap ,and i s said to come from the F icus I ndica.

MA NDARNVA RUBBER— A low grade of South Americangum , somewhat l ike Ceara rubber . Littl e known . I s said togrow on the dry arid uplands of the interi or. I s one of anumber of gums that bear the native names , “

Cauchin,

”

“P an,

” and “M assaranduba .”

MANGA- I CE RUBBER—A rgentine republic . I t is veryabundant . P roduces good rubber .

MUDAR GUM .—This comes f rom an A sclepiad, commonlyknown as gigantic swallow wort (Calotropis gigantea) . The


Shrub i s found throughout the Southern provinces of I ndiaand grows to a height of from s ix to ten feet . P roduces agutta- l ike sub stance, which becomes plastic in hot water, andin other ways acts somewhat l ike gutta-percha . I t insulatesbadly , but i s recommended for waterproofing. A nalysi s :Rubber, per cent . rosin, per cent , according to War

den Hooper found per cent . of a rather poorrubber, and 62 per cent . resin .MUSA GUM .

-A gum expres s ed from the pee l and leavesof the banana and pisang plants . N o gum yet on the market .P roces s patented in E ngland by O tto Zurcher

,of Kingston

,Jamaica . A l so cal led “banana rubber” (which see ) .

NA M AQUA LA ND RUBBER (Euphorbia drag eana) — A' new

source of rubber growing wild in the uplands of Namaqualand ,South A frica . I t i s said to yi eld per cent . pure rubber and70 per cent . res in .

NEEN RUBBER— A rubber- l ike gum said to be produced byan insect , reported from Y ucatan . The insect belongs to thecoccus family , feeds on the mango tree , and swarms in thoseregions . I t i s of considerab le s iz e , yellowish brown in color,and emits a pecul iar O i ly odor. T he body of the insect contains a large proportion of greas e , which i s h ighly prized bythe natives for i t s medicinal properties i n skin di seases . Whenexposed to great heat , the lighter oi l s of the grease volati l ize ,l eaving a tough wax which resembles shel lac . When burntthi s wax produces a thick semi-fluid mass , l ike a solution ofindia rubber . A n

“ant wax” or lac i s found in M adagascarand is secreted by two insects , Gas cardia M adagas car iens is andGas cardia P errieri . The former secretes a white gum,

containing 52 per cent . of re s in . The latter secretes red gum, with 46to 48 per cent . resin . The two gums have the same value .

O COTI LLO RUBBER— A plas tic extruded from the ocoti l loplant (F ouquieria splendens ) , a shrub common to Texas , A ri

zonaa nd Northern M exico .P ALA GUM - F ound in A s sam and Ceylon . The wood and

the bark are valued in I ndia for thei r medicinal qual it ie s . Thetree yi elds an abundant milky jui ce , which after coagulation

P A LO AMARILLO— TA LA ING RUB B ER 41

acts something l ike gutta-percha . I t readi ly softens in hotwater and takes impres s ions , which are retained when cold .Al so known as I ndian gutta-percha .” Comes f rom the Dichops is elliptica. I t has been used as an adulterant o f S ingaporegutta for some years . I t was used al so as bi rdl ime or cementand keeps wel l under water. I S hard and britt le when cold .The res in i s eas ily removed by boil ing alcohol , and the res idueappears to b e a very fair gutta .

P ALO A MARI LLO .— A varni sh- like gum from the latex ofthe M exican tree E uphorbia fulva. A nalysis of the l atex gives

34 per cent . gum and 6 per cent . res in . So far the gum i s notsusceptib le O f vulcanization and i s not elasti c .P ALO COLORADO —A M exican g rade derived from the tree

known as palo colorado in the state of Durango .P . F . U.

—A good rubber, not now obtained commercial ly ,the source O f which was the Colorado dese rt weed , the P icradenia

‘

flor ibunda utilis .

P I CKEUM GUM — See Guayule .SARUA RUBBER— F ound in the F ij i archipelago , from A ls to

nia plumosa. F ormerly collected largely, but l ittl e comes nowto the market . N atives take no interest in its coll ection . The

juice comes from the stems and '

leaves but not from the trunkof the tree . I t i s soft at firs t but coagulates almost at once ,hardens after a time , and b ecomes inelast ic , of about the colorand consi s tency of putty . I t i s gathered by the natives duringa season of three months .

SE I BA GUM — See Tuno .SUSU- POKO (meaning E ngli sh tree milk ) .

— A gum from atree growing in the M alay peninsula, us ed in the place of

gutta-percha,afte r being cleansed and treated with chloride of

sulphur . M entioned by Leonard W ray in 1858.

TA LOTA LO GUM — F ound in the F ij i archipelago . Comesfrom Tabernceni ontana Thurs toni . The gum is hard , guttalike , and without e las ticity . A l s o cal l ed “

Kau Drega . The

milk i s thin, but the tree grows large, up to two feet i ndiameter, and i t i s the bes t rubber source in the F ij i i s lands .

TALA I NG RUBBER—A n almost b lack rubber which , whencut into , i s white and porous presenting a honeycombed ap

.42'

LI TTLE KNOWN RUB B ERS

pearance , the cavit ies b eing fil led with a watery fluid . I t i squi te tough and elastic and appears to b e of good quality . I t

comes from a creeper which is abundant in the P hi lippines ,in M alacca , and I ndo-China . The juic e i s very abundant , andi s coagulated by being boi led in water .

T I RUCA LLI GUM .— This i s a Euphorb ium gum ,

from theI ndian plant known as m i lk hedge . The milk—oi th i s plant i sused for various purposes , chiefly medicinal , in I ndia, and hasbeen suggested as a sub stitute for gutta-percha . Like gumEuphorbium ,

i t has a very acrid character, and the collectionof i t i s a very dangerous operation to the eyes . When d ry e it

becomes very brittle,but .when warmed in water i s quite

elast ic .TOUCH P ONG GUM .

—This i s without doubt a rubber gum ,

entire ly di stinct from balata . The rubber dries in strips on thetrees

,and what li ttl e of i t comes to market has not b een recog

nized as a distinct sort . Samples sent to E ngland,however,

have been favorab ly reported on . I t is found throughout theGuianas . P robably from Sopium big landulosums Spelled“touchpong

” by Jenman ; touchpong” by M orri s ; “pouck

pong” by Dr . Hugo M i l l er.A nalys i s of touchpong gum by the Imperial I nsti tute ,

London,gave per cent. rubber and per cent . res in .

TU CHUNG RUBBER—This i s a valuable gutta derivedfrom the Eucomnu'a ulmoides

,or the chung tree, native O f China .

I t has been definitely establ i shed that this tree can be readilyacclimated in temperate countri es .

TUN O i s a trade name appli ed to a gum gathered principal ly in N icaragua and Honduras . I t i s the product of whathas been cal l ed the “s teri le rubber tree” and al so the “malerubber tree” of N i caragua . I

The milk is coagulated with theaid of heat . The gum i s but sl ightly elastic , i s very stickywhen heated , and is cheap . I t i s used as a friction gum , andi s al so mixed with balata in the manufacture of belting. Sometimes it i s s old under the name of “Seiba gum,

” i t s identi tybeing lost by ingenious mas sing and manipulation under water .N icaragua rubber adulterated with “

Tuno” in coagulationsoon hardens and loses its elast icity. A l so spelled “

Toonu”

CHA P TER III.

CO AGULATION O F RUB B ER LATEX .

WITH the advent of the chemist in the rubber factory anexact knowledge of the various treatments to which indiarubber may b e sub j ected in forest or plantation i s not onlyinteresting but O ften of the greates t value . F or thi s r‘easonthe fol low ing review of coagulat ing processes and sys tems isgiven at some length .

Rubber latex is a mixed suspens ion and solution of rubber globules , res ins , nitrogenous bodies (albumens or proteins ) , and saline substances contained in a watery mediumor serum .

Typical Hevea undiluted latex from Malaya (average from100 ten-year-O ld trees by Beadle and S tevens ) .

P er cent.Rubber

The proteins are in col lo idal solution and are capab le of “

being precipitated by certain reagents,notably acids . Latex

being a comb ined solution and suspension , has many‘

of thecharacterist ics of a colloidal solution . I t seems probable thatthe protein acts as a protective colloid to the pure caoutchoucpresent due to the adsorption of a layer of the dis solvedprotective agent over the Surface of each of the sus

pended rubber particles .F our wel l-defined stages in the degree of coherence

‘

of

rubber separated from latex have been noted by a writer i nthe “Tropical A griculturi s t ,” namely

1. Creaming i s the condit ion observed in the early stagesof s low coagulation .

SM OKING 45

2. F locculence refers to the formation'

of small particle sof rubber without coalescence into lumps . Thi s state i sob servable in latex to which much formalin has been added .

3 . A gglutination , or local lumpy coagulation , observedwhen latex c oagulates spontaneous ly , or when certain mineralsalts are added .

4 . Coagulation proper i s the final s tage observed oncareful addition of acids to latex , the rubber forming in oneclot and leaving a clear liquid .

The purpose of coagulation i s the separation of the rubber sub stances from the watery or s erum port ion of the latex .The diff erences between unl ike grades of rubber are duepartly to chemical composition , and also in a measure to varying methods of col lection and coagulation . I t i s undoubtedlytrue that no one method of col lection would b e best for al lkinds of rubber gathered , even if it"were poss ib le . I t i s important to the rubber manufacturer to know what sys tems arepursued , and particularly what ingredients are added , to produce coagulation , that he may standardize hi s compounds inrespect to rubber qual ity .

There are four basic methods O f coagulating rubber latex1. Smoking.2 . Drying .3 . Separation by chemical s .4 . M echanical s eparation .SMOK I NG rubber is the system with which the world at

large i s most familiar, and i s practi sed in the Amazonian forests in the col lection of P ara gum. Several kinds of palm nut sare used to produce a thick smudge

,but those preferred are

from the Urucuri palm (A ttalea excelsa) . This smoke hasbeen found by analysis to consist mainly O f acetic acid andcreosote , the latter being a wel l known preservative of rubber .F ine P ara rubber i s nearly always smoked in thi s way . CoarseP ara i s ai r dri ed . There are al so trees found in the forestswhere i t i s imposs ib le to get palm nut s ,, the wood of which i sused succes sful ly for the coagulating smoke .

Smoke fumes,in addition to their coagulating action ,

exert a preservative eff ect by impregnating the coagulatedgum with creosote and formalin . Coagulation by smoking

46 COA GULA TI ON O F RUB B ER LA TEX

evaporates a considerab l e portion of the water contained inthe latex. The temperature of the smoke close to the rubberin the native smoking O f wild P ara is about 160 degrees F .

DRY COAGULATI ON— HEAT, A I R,SUN LIGHT.

— Various rubbers are coagulated s imply by the exposure to sl ight artificialheat , to the sunlight, or merely to the air . Such are the coars eP ara rubbers , certain O f the Centrals , A frican , and E ast I ndianrubbers . F ij i rubber i s coagulated in the mouths of the natives ,and some A ngola rubber by evaporation on the arms andbreasts of the natives .

Some k inds of rubber dry di rect ly on the tree and areremoved in the shape of rubber threads compressed into largelumps or wound . S crap of al l descript ions of rubber i s generally O btained in wild and plantation Culture through drying,in many cases with the help of chemicals . There i s also , insome cases

,s imultaneous addition of certain decoctions (suchas tannic acid , soap , salt , A n important drying process ,

in conjunction with the use of chemicals i s the Leva proces s .di scovered by Dr . H indorff and us ed in the production O f

plantation Manihot rubber. In thi s process the tree is previous ly coated w i th the extract ive chemical s olutions , the barki s next cut w i th a rounded knife . The latex which exudescoagulates whi le running down and i s gathered from thetr

'

tInk.

A direct tannin drying process,

first defined by A . Schul te ,for F untumia (Kickxia) , i s Operated as follows :

F untumia latex is poured into a pan and sprinkled withtannin solution . The vessel i s shaken and soon the mas s canbe turned in the mold l ike a pancake . The uncoagulated Sidei s then sprinkled with tannin and the movement continued .F inal ly the cake thus formed i s squeezed through a wringerto extract the water.

SEPARATI ON B Y CHEM I CALS .—M any chemical s exerci s e a

separating influence in the extraction of rubber from the latex.The first coll ectors of wild rubber used these influences asthey exi st i n the form of smoking and plant juices

,as well

as in soaps and salts ; also in the natural forms of perspiration , sal iva and urine .

ME CHAN I CAL SE P ARA TI ON 47

I t was at firs t thought that the acti on of acids uponcoagulation was only due to the insolubi l i ty of the albuminoid s containing the globul es of rubber. M . H enri h as s inceshown that with latex freed from its salt s or crystal loids

,

acids do not produce compl ete coagulation,but only the

agglutination of the rubber. In ordinary Hevea latex all acidsproduce coagulation , but the proporti ons of organic acidsneeded for that resul t are larger than in the case with mineral acids . The former are preferred on account of the corros ive action of the latter (such as sulphuri c , nitric o r hydrofluor ic acids ) upon the impuriti es which remain in the mass ,as well as upon the metal l ic portions of the plantation factoryplants .W i th respect to albumen , Dr . F rank concludes regarding

chemical means of coagulation1. A l l agents wh ich precipitate and denature albumen

operate toward separating the rubb er .2 . Separating agent s which exerci se a decomposing in

fluence upon the accompanying albuminous substance , or leadto i t s decomposition , require in addit ion to the coagulatingagent, the S imultaneous presence of preservatives . Sub stanceswhich do not exerci se such a decomposing eff ect can be usedby themselves .

MECHAN I CAL SEPARATI ON .—The real mechanical method

for removing the rubber substance from the latex i s the centrifugal system by which a centrifugal machine removes thewatery contents and produces a marvelous ly clear elasticrubber. This process is particularly suitable for F icus latex .I t also seems adapted for Hevea latex

,but in the latter case

acid should b e added previous to the centrifugal action .A mechanical proces s of separation used on a large scal e

in the Dutch colonies , for the coagulation of F icus latex, cons i sts of subj ecting the s trained latexto the action of a beateror twirl ing rod . The addition of the thickened , creamy portion from latex which has been standing, material ly hastensthe separation and renders the proces s practical .

A nother mechanical proces s is that of P rofes sor Danerfor Cas tilloa, in which foreign substances, particularly thoseof an album inous nature

,are separated by dilut ion .

48 COA GULA TI ON O F RUB B ER LA TEX

The fol lowing descriptions embrace the ordinary material s employed for coagulation as wel l as certain patentedmachines and proces ses .

A MOLE JUI CE — A native proces s for coagulating the milkof the rubber tree,which prevai l s throughout Central America

,

involves the use of an alkaline decoction made from the juiceof a plant called “achete” or “coasso” (Ipoincea bona-nox

,Linn .,

and also Calony ction speciosurn) . This is combined with rub

ber mi lk in the proport ion of 1 pint to 156 gallons of the latter .During coagulation the vessels are O ften ' heated from 165 degrees to 175 degrees F . A fter coagulation , the rubber is dried fortwelve to fourteen days . The kinds o f rubber coagulated in thisfashion are M exican , N icaraguan , and in fact almost al l of therubbers that come under the head of Centrals , and are obtained from the Cas tilloa elas tica.

A CETI C A CID— Used in coagu lating Hevea latex in the F arE ast . Thi s acid

,originally suggested by P erkins in 1898, i s

now us ed for coagulation in about 98 per cent . of the plantation rubber produced .

A LCOHOL.— O ne of the bes t general coagulant s,but too

costly to be commercial ly available .A LUM .

— Th i s i s us ed al l through the is thmus of P anama ,and in coagulat ing A ccra rubbers and Other A frican sort s .P ernambuco rubber i s al so treated with a water solution ofalum , as i s the N i caraguan at times .

BOSAN GA.— The juice of the Costus afer , a seed used inthe coagulation of the latex of Landolphia in the Lopori distriet in central A frica .COCON UT WATER— F ermented coconut water has been

found to be a cheap , sati sfactory sub sti tute for coagulatingHevea latex in place o f acetic acid .

COYUNTLA JUI CE—This i s an astringent juice made fromthe M exican weed of that name . When the rubber milk i sgathered , i t i s placed in earthenware vessel s and whipped withthe weed ,

which causes coagulation . The M exican rubberknown as Tuxpam I S treated in this way .

F ORM I C A CID— Used instead of acetic acid in coagulatingHevea latex .

HELF ER P RO CESS— SERINGUINA 49

HELF ER P ROCESS .—This cons i s ts of the addition of a solu

t ion of acetic acid , and i s based on the knowledge derivedfrom the analysis of the smoke of the Urucuri nuts .

KOA LA TEX .— A proprietary preparation us ed in Ceylon

and the F ederated M alay S tates for coagulating the latex ofthe Hevea B ras iliens is .

LIME - A final process in the coagulation of rubber inI ndia i s the washing over with l ime . Coll ins also mentionsthe us e of l ime in connection with the coagulat ion of P ararubben

LIME JU I CE — Lagos rubber and some other A frican sortsare coagulated by the addition of a li tt le l ime jui ce

,which is

added as the milk flows from the vine .N I P A SALT.

— A sal t obtained by the burning of the plantknown as the Nipa fruticous . I t i s used in the coagulation ofB orneo rubber.

MACHACON JU I CE — Cartagena rubber, which i s gatheredcareles s ly

,i s coagulated in a hole in the ground by the addi

t ion of the jui ce of the foot of the machacon”— a stronglyalkaline solution .

P OZELI NA .— A preparation intended to keep rubber latex

in a fluid condition unti l the time of curing . The ingredientsus ed in making the preparation are secret . The headquartersfor i ts sale are at P ara

,B razil .

P URUB .—A nother name for hydrofluori c acid , when pre

pared as a coagulant of rubber latex .SALT—M any kinds of low-grade rubber are coagulated by

the addit ion O f salt or brine . B orneo,for instance , i s coagu

lated in that way . M adagascar rubber receives a treatmentof salt-water. M angabeira rubber is treated with a mixtureconsi sting of 1 part of salt to 2 parts of alum . N i caragua rubber is a ls o often coagulated with sal t .

SERI NGUI NA .—A chemical product for retarding for any

length of time the coagulation of rubber latex . I s said to contain no corrosive elements . When the latex i s final ly smokedthe substance evaporates entirely . I t i s the invention of Dr .

Cerqueira P into , of P ara , B razil .

50 COA GULA TI ON OF RUB B ER LA TEX

SOAP A ND WOOD A SHE S .— The medium-grade rubbers all

through Central America are often coagulated by the use ofsoap , and where that i s not’

plenty , of a strong lye from woodashes .

SP IRITS O F W I NE—This i s used sometimes in the coagulation of balata .SULPHUR F UM Es .

—A ccording to James Col lins,rubber of

the P ara varieties i s sometimes exposed to the act ion of thefumes of melted sulphur, which aff ects coagulation . Thisproces s , however, i s very rarely followed .

TORRES SYSTEM .— I n addition to the natural methods de

scrib ed above , there are several that give some evidence of anintel l igent s tudy of the mi lk and the substances best adaptedfor this work . Under the Torres system a liquid i s made bya secret formula , from the roots and frui ts of certain SouthAmerican palms , which , when added to the mi lk, preserves itfrom curdling, so that i t wi ll keep for weeks . I t can thus betransported to a convenient place for smoking.

COAGULATI NG MACH I NES.B ETA SEPARATOR.

- The i nvention of M r . John H inchleyH art, of Trinidad . This i s an arrangement by whichthe latex placed in the upper compartment i s washed

,filtered ,

and'

coagulated . The machine known as the B eta separatorworks somewhat on the principle of the cream separator.

CoUTI NHo’s MACH I N E —Thi s i s a wooden cylinder about

20 inches in diameter, set horizontal ly , revolving by a crankand SO arranged that smoke i s let into the ins ide through the ‘

cylinder shaft . The latex , by the revolution of the cyl inder,i s di stributed over it s inner surface and there smoked andcoagulated .

DA N I N’s machine for smoking rubber i s a revolvable

cylinder,through openings in the end of which smoke i s forced .

the latex firs t having been introduced through the other end ofthe cyl inder . The cylinder being rotated , the latex spreadsitself over it s inner circumference and i s carried past the discharge end of the smoke condui t and thus coagulated . The

machine is the invention of J . R . C. Danin , of P ara , B razil .

52 COA GULA TI ON O F'

RUB B ER LA TEX

coagulat ing cylinder at a point suffi ci ently above the levelof the latex in the cylinder to enab l e each fresh film to formevenly before it arrives in front of the smoke j et . O thersui tabl e agents may be used in place of smoke .

E LECTR I C COAGULATI ON .— Coagulation of rubber latex by

electri city has been succes sful ly performed on plantationswhere acetic ac id was scarce . This coagulation is eff ected in aporous vessel with carbon electrodes

, us ing a low tens ioncurrent . The latex i s s l ightly di luted with water and the gums eparates very rapidly . I t i s perfectly clear and l impid .

CAUSE O F COLOR I N CRUDE RUBBERThe darkening of smoked P ara has been demonstrated to

be caused by an oxydase or oxidizing enzyme present in thelatex and its action on certain oxidizab le sub stances natural lypresent in the latex, but which may be added to by the smoke .

Dr . David Spence has made some very profound andpractical researches on the matter of the darkening of rubber on exposure to the ai r and hi s description O f the enzymescausing this eff ect is here appended

“These enzymes are probably

,as I l earned , present in the

protein of the latex O f al l rubber-producing plants , and so actupon the insoluble portion of the protein that it i s convertedinto colored products , which impart the dark color to the rubber . I n my original work I determined that the temperatureat

'

which the oxidizing enzymes are destroyed lie s very closeto the point where in general other s imi lar enzymes peri sh .To O btain rubber only sl ightly darkened , i t seems , at firstglance

,only neces sary to destroy the active enzymes in the

latex or the rubber b y heating above the steri liz ing temperature , 75 degrees C . B ut this method of destroying the enzymes bymeans of heat i s not so easi ly accompli shed in practice , andthis fact leads me to the beli ef that in the latex and in therubber there was a heat- res i sting agent , zymogen , whichslowly changed into active enzymes .

“I found

,for examp l e

,that freshly cut pieces of P ara

rubber,washed thoroughly with water for more than an hour

to remove the strongly colored solubl e matters , graduallydarkened and -after exposure to the air finally became entirely

COLOR IN CRUDE RUB B ER 53

black. P otass ium cyanide , a mercury chloride solution oracetic acid

,fai led to prevent the dark coloration , or at least

after the above solutions were completely removed by washing. I made many experiments with the latex of F untumiaelas tica, but found without exception that heating the latexor the rubber prepared therefrom even to 100 degrees C . forhalf an hour was insuffi cient to al ter the tendency to turn dark .

“I t i s known that certain natives on the W est A fri can

coast Obtain rubber f rom the latex of F untumia e las tica byheating it with water unti l the separating rubber parti clescoalesce into ball s . N evertheles s , I have seen no sort of rubber prepared in thi s manner in which the eff ect of the activeoxydase enzyme was not plainly ob servabl e .

“S ince the oxidiz ing enzyme i s very stable towards heat ,

the bes t method for handl ing the latex to secure only faintlycolored rubber appears to be the one pres ented previous ly byme and now repeated here . B y thi s method the enzyme itself ’i s to be removed as completely as pos s ib le b efore coagulation .The latex is diluted with water before the coagulation and theagglomerating rubber parti c l es washed wel l (thi s appli es atleast to F untumia elas tica ) in order to remove the oxidizingenzyme as wel l as other foreign matter from the rubber. I n

this manner a snow-white rubber i s obtained . Y et to preventas much as poss ibl e the baneful eff ects when us ing the boi ling proces s a substance having a noxious action against theenzyme but a harmles s one towards rubber could b e uti l ized .”

Subsequent to these observations of Dr . Spence , the researches on thi s prob lem by B eadle and Stevens resul ted inthe discovery that the addition of one part of sodium bisulphiteto 500 to parts of latex neutralizes thi s enzyme withthe result of producing a permanently very pale rubber . Thi streatment i s without injury to the rubber qual ity and i s particularly adapted to white and transparent goods .

I t should b e remarked that color i s not an indication ofquality ; al so the defects of appearance ari s ing from variouscauses and known as oversmoking

,have nothing to do with

qual ity, and the sam e i s true of the appearance of smal l bubb les in the sheet .

CHAP TER lV

VULCAN IZ ING P RO CESSES A ND INGREDIENTS

P LA NTATIO N HEVEA A ND THE O P TIMUMCURE .

TH E means for vulcanizing india rubber in general useare roughly two : the heat cure and the cold cure . Considering the first , a great vari ety of goods i s cured in open steamheat and i s kept in shape during vul canizat ion , either inmolds or by being wound with strips of cloth or buried inpans O f F rench talc . Thi s is the wet heat and such goods arecured in vulcanizers , big and littl e , of which there are manyforms . A diff erent application of heat i s what i s known asdry heat , where goods are put in a hot room without wrappingor mold protection , and left unti l vulcanization i s effected .A nother heat cure which at one time was very largely used ,but to—day has practically disappeared , was what was knownas solarization . This cons i sted in expos ing fabrics coatedwith a thin skim of rubber to the rays of the sun

,which

eff ected a surface cure .A special heat cure adapted to very particular work, such

as curing pure rubber thread sheet,i s the water cure . In thi s

method the rubber receives the vulcaniz ing heat by immers ionin water rais ed to the required degree .What i s known as the cold cure has been practiced since

the days of Goodyear , and within ‘the last few years has been

much resorted to in the manufacture of certain l ines of goods .This in turn , divides i tse lf into two methods— the ’ac id and thevapor cure . I n the former , one-half pound of chloride of sulphur i s mixed with four pound s ‘

of b isulphide of carbon . Thegoods are dipped in thi s solution and afterwards treated withan alkal ine wash . The vapor cure i s where the fumes ofchloride of sulphur are set free in a heated room or cabinet i nwhich the rubber '

goods are suspended so that al l of the surface i s aff ected . When the cure i s far enough advanced the

EARLY INVENTORS 55

further action of the chloride of sulphur fumes i s stopped byammonia fumes .While Charles Goodyear’s patents for the vul canization

of india rubber by the use of sulphur and heat were in force ,a marvelous amount of ingenui ty ’was shown in the attemptsto accomplish the same results by the substi tution of otheringredients for sulphur, either with or without the use of heat.These

‘experiments and inventions embrace vulcanization , bymeans of chlorides

,nitrates , nitrites , fluorides , bromides ,

iodides,and phosphorets of about al l the common earths and

metal s,and also many gas es such as sulphurous acid gas .

The maj ority O f these experiments have been lost s ight of,partly because the Goodyear proces s i s now open

'

to the world ,and partly because , for the maj ority of goods , the sulphur andheat cure i s not only the ’cheapes t , but the eas ies t to accomplish . I t may be well

,however

,to review and record the

experiments i n thi s l ine , as there i s no ‘doubt that for specia ll ines in rubber manufacture many of them have a sugges tivevalue to-day .

O ne of the very first ingredients to which inventors andexperimenters turned their attention was z inc . The veteranrubber ‘manufacturer , Jonathan Trotter, described a processfor preparing a vulcaniz ing material which he cal led hy posulphite of z inc . I t was made from a solution of caustic potashsaturated with flowers of sulphur and then treated withsulphurous acid gas . This solution he mixed with a saturatedsolution of n i trate of z inc

,forming the prec ipitate ’

that hedes ired . H e used 3 pounds of hyposulphi te to 10 pounds ofrubber, curing from 3 to 5 hours , at 260 degrees to 280 degrees F .

‘ E . E . M arcy , an American , some years later patented acompound of hyposulphite of z inc and rubber which is apparently almost identical with Trotter’s di scovery

,although he

di sclaimed S imilari ty,and also made public the process , in

which he used a combination of h yposulphite of z inc andsulphide of z inc , the ‘ compound being 2 pounds of rubber, 1pound sulphide of zinc

,1

' pound hyposulphite of zinc , andother ingredients as deemed neces sary . These goods were ofa beautiful white color, were said not to bloom , and did not

56 VULCAN IZING P RO CESSESneed the sunning proces s then in use . A t the same time theydepended upon sulphur and heat for whatever vulcaniz ingwas accompli shed .

A nother attempt to get a good sub stitut e for sulphur wasin the production of what i s known as sulphite or hy pOsulph ite of lead . James Thomas describes at length a compoundin which he mixes hyposulphite of lead and artificial sulphideof lead

,in equal proportions , hi s compound being for vul can

ization,2 parts by weight of india rubber and 1 part of the

vulcaniz ing material .F ollowing thi s thought came E . E . M arcy again

,who

mixed sulphide of lead and carbonate of l ead in the proportions of 2 parts of sulphide of l ead

,1 part carbonate of lead

,

and 2 parts protoxide of l ead in place of the carbonate .Then O scar F alke and A lbert C . Ri chards b rought out a

compound cons isting of 6 parts india rubber , 2 parts sulphideO f antimony , and V2 part sulphite of soda , curing at 270 degrees to 280 degrees F .

A . K. E aton , in no uncertain terms , di sclaimed vul canization by the use of free sulphur, but claimed to be the first touse sulphide of manganes e . H e also gave a formula for making it , which was by mixing intimately 44 part s of peroxideof manganese with 32 parts of sulphur

,and exposing the mix

ture to heat in a covered crucib le . H e vulcanized severalhours , from 250 degrees to 3 10 degrees F .

George Di eff enbach c laimed sulphite of alumina as aningredient which

,in connection with heat

,would bring about

vulcanization . H e us ed this in a compound for a dental rubber, which had for it s basi s india rubber, amb er, l inseed oi l ,sulphide of cadmium , oxide of tin , vermil ion , and pulveri zedfeldspar.Charles T . Harri s cured india rubber by combining itwith an artificial sulphide of b i smuth

,wh ich he explained as

being the artificial tersulphide , or polysulphide of b ismuth .

He describes thi s as being a heavy b lack powder , and thecompound which he advi sed for soft rubber was 100 partsindia rubber

,75 parts carbonate of lead , and part s poly

sulphide O f bismuth , cured in a dry heat at 245 degrees F . forIV: hours .

EA RLY IN VENTORS 57

Henry W . Joselyn discovered that shale combined byheat with sulphur formed a sulphide wh ich could be us ed incuring rubber, and hastened to patent it .

A ndreas W i l lman brought out a proces s for combiningindia rubber with “anhydrous ch lorides , sulphates

‘

of alkalie s”and powdered coke or coal , and claimed that hi s best resultcame from chloride of ammonium and coke . H i s compoundwas made up of l itharge, lampblack , and powdered coke , inconnect ion with from 2 to 10 per cent . of hi s

,vulcaniz ing

mixture.E dwin L . S impson formed a vulcaniz ing compound by

mixing benzoin gum with pulveri zed sulphur , and boil ing itin linseed oil . I t was used in ;a dry heat, the compound being1 pound of india rubber, 2 ounces vul caniz ing compound , 8ounces l itharge , and 8 ounces whiting .J . A . N ewbrough manufactured a vulcanizing material

which he cal led acid resin , made of turpentine and sulphuricacid . This he incorporated in india rubber in the proportionof 6 ounces of acid res in to 1 pound of india rubber, andcured at 300 degrees to 320 degrees F .

The use of selenium as a curing agent was discovered byE . E . M arcy , whil e connected with H orace H . Day , thenprominent as a rubber manufacturer . He advi sed the use ofequal parts of india rubber and powdered selenium

,and , to

produce‘ a glos sy fini sh,he added selenium carbonate and

wh iting .A t the same tim e there were many other inventors who

were experimenting with proc es ses that were somewhat inthe l ine of the well-known P arkes coldcuring proces s . F or

example , it i s a matter of hi story that the late Joseph B anigan ,early in hi s career as a rubber manufacturer , cured wringerroll s by an acid proces s .

Dubois C P armelee invented a proces s which he cal ledherm iz ing , to . dist ingui sh it from curing or vulcaniz ing,in stead of the P arkes proces s , in which the solution of chlorideof sulphur and bisulphide of carbon was used . He recommended briefly a solution as fol lows : 10 pounds of coal-tarnaphtha

,in which was di s so lved 1 pound of sulphur . I nto

thi s solution he passed dry chlorine gas unti l i t as sumed a fine

58 VULCA NI ZING P RO CESSESyellowish-green color. This solution he used as a dip for suchgoods as would b e cured by the acid "treatment . P armeleealso claimed the di scovery of a solution made of coal- tar naphtha

,bisulphide of carbon , and a solution of sulphur in bromine ,

mixed w i th this .R . F . H . Havermann reduced india rubber ‘

to a solut ionand subj ected i t to the action O f chlorine . H e also , in a laterpatent , described the washing of the chlorine out of the rubberby alcohol , and the addition of ammonia and lime , the resul tbeing, according to his specifications , a white , hard rubber.Working in the same l ine , John Helm , Jr di ssolved indiarubber in benzine and mixed i t with liquid chlorine in the

proport ion O f 12 ounces of chlorine to 1 pound of gum . H is

claim was that he could get rubber of any color and of anydegree O f hardnes s by this process .

H . A . A yling patented a coldcuring proces s in whichcarbon spirits (naphtha ) , one of the petroleum series , wasmixed w ith chloride of sulphur

,instead of the usual b i sulphide

of carbon .I n the line of hard rubber manipulation and vulcaniza

tion , L. O tto P . M eyer (then connected with the I ndia RubberComb Co .) patented a proce s s for curing vulcanite in a ves selwhol ly or partly fil led with water, the water in which therubber was contained being in a tight receptab le, and the heatbe ing raised above 300 degrees F ., the pressure of the surrounding steam keeping it from vulcaniz ing. Thi s obviatedthe danger of burning

,and was of great value in the produc

tion of certain goods .While these and other inventors were try lng to curerubber without sulphur, and without interference with the

Goodyear patents , certain others were at work on other gums .F or example , John R ider, who was at the head of a guttapercha company

,produced what he cal led mettalothy anizedgutta-percha . I n thi s , he first heated the gutta-percha , then

mixed 3 pounds of hyposulphite of lead and zinc with 8

pounds of gum,and sometimes added also a li ttle P ari s white ,

or magnes ia . He then put the compound from 2 to 10 hoursin a dry heat and cured it at 280 degrees to 320 degrees F .

John Murphy changed this compound somewhat, by ad

60 VULCAN I ZING P RO CESSESkeep them from adhering . P roof cloth i s cured in vapor bypassing the rubber surface over troughs in wh i ch thi s reagenti s S lowly evaporating .

P arkes al so suspended articles to be vulcanized in a dryheater and passed the following gases into the chamber as ameans of vulcanization : Sulphurous acid , gas , chlorine , nitrousacid , or the vapors of brom ine or iodine .Charles H ancock cured rubber by the acti on O f vapors

produced by dis solving zinc, copper, or mercury in nitri c acid .The action of these vapors being so act ive , only one or twomoments were given , and the surfaces then washed in an alkal ine soluti on .

N i ckel s pas sed sulphur fumes and hydrogen into the gumwhile in a masticator, curing afterward by heat .Caulb ry

’s process i s s imilar to that of P arkes’s , by which

it i s c la imed rubber can be vulcanized at ordinary temperatures

,by us ing an intimate mixture of chloride of sulphur

and dry chloride of lime . During thi s mixture , and when thesmell of the chloride of sulphur wi l l be noticed , the temperature of the mixture wi ll ri se , the mas s becoming plastic bythe softenlng of the sulphur. I f a mixture of thi s kind , inwhich sulphur i s in great excess , be added to the solution ofindia rubber in b i sulphide of carbon , the rubber will b e vulcanized at an ordinary temperature , or perhaps with a sl ightwarming. Chloride of sulphur us ed pure i s too corrosive ini ts eff ect on india rubber ; i t i s therefore reduced in al l cases .O nly thin articl es can be vulcaniz ed in thi s way .

A patent taken out in E ngland by E dmond Garnierrelates to the vulcanizat ion of india rubber by the use of alum .

P revious ly alum proces ses for curing had not b een very succes sful , but thi s patent had some novel features . I t call ed forparti cularly dry alumt reated with a solution of terebinth ofbenzol and shel lac

,or some S imi lar gum. I n use he took 8

ounces of alum and a solution composed of 1 part gum and20 part s b enzol . He mixed the ingredients that are usuallyemployed in the manufacture of rubber, specifying 3 poundsof whiting

,1 pound bary tes , 8 ounces l ime , 1% pounds oxidized oi l

,and 8 ounces of india rubber. When these had been

thorough ly mixed together and special ly treated , alum was

ULTRA -VI OLET RA YS— OLI VI ER’

S METHOD 61

incorporated with them and well compounded,being pas sed

through the mixing rol lers cold . I t was then calendered .Raymond

,in another Engl ish patent , use s for vulcaniz ing

a mixture of benzine,camphor

,ch loride of sulphur, and ole icacid .

VULCAN I ZATI ON BY ULTRA-VI OLET RAYS .

VULCAN I ZATI ON by ultra-violet rays was brought to theattention of the rubber industry by Dr . Helbronner and Dr .

B ernstein , at the I nternational Rubber Conference at London in 1914 . I t i s said that V i ctor Henri in 1909- 1910 wasthe first to expose rubber to the ul tra-violet rays

,carrying

out vulcanization with films of solution . F rench patent NO .

i s sued July 26, 1913 , int ernational conventions , dateJuly 26, 1912, c laimed the vulcanization of rubber solutionsby ul tra-violet rays and states that 3 per cent . plantationrubber and sulphur in benzine exposed in thin layers vulcanize rapidly , sulphur to the extent of from 172 to 2% percent . combining with the rubber .Crystal l ine sulphur, rather than flowers of sulphur or

stick sulphur, should be used and the interesting suggestion1s made that thes e solutions of rubb er so vul canized may haveindustrial app l ication . They are said to be sui tab le for allkinds of cementing or rubberiz ing operations , and are capableof res i st ing al l mechanical strains

,as well as the action of

heat . They can be us ed particularly for j oining and rubberizing leather, and consequently will b e valuable in the shoeindustry .

A l so,the repairs of al l rubber goods , tires , inner tubes ,

etc ., can be readi ly carried out by means of vulcanized solut ions .‘

Two other patented methods of vulcanization by ultraviolet rays may b e mentioned .

OLIVI ER’S METHOD.

TH E rubber solution , containing free sulphur, with orwi thout certain organ i c or I norganic sulphides which are decomposed by ul tra-violet rays

,such as carbon b isulphide ,

allyl sulphide,or antimony sulphide , passes from a hopper

on to an endles s steel b and,which is carried by guide rollers

62 VULCAN I ZING P RO CESSESround the greater part of the periphery of a mercury-vaporlamp . The lamp is surrounded by a double , hemicylindri calwater-j acket of quartz , in order to cut off heat rays . The timeof exposure i s quit e short , in order to avoid the deleteriouseff ect of prolonged exposure to ultra-violet radiat ion on therubber. A s an example, a layer of solution a fraction of amill imeter thick, at a distance O f 5 centimeters from the lamp ,which i s Operated at 220 volts and 3 amperes , requires anexposure of about 40 seconds . A fter pas sing the lamp thesolut ion i s removed from the endles s band to a receivingvesse l by means of a scraper.

BERN STE I N ’S METHOD.

TH I S consists in the exposure of rubber solution containing sulphur , sulphide , or other vulcanizing agents to theaction of ul tra-violet rays under conditions to sui t the circumstances , such as in vacuo, under heat and pressure, or in anatmosphere of neutral gas not containing oxygen .

Helbronner and B ernste in consider vulcanization as amere polymerization of the rubber under the action of a catalyti c agent (sulphur ) . The sulphur becomes insoluble andunites with the india rubber. A certain action of the rubberi s caused by the ul tra-violet rays , and another by the sulphur ,and the combined actions produce vulcanization . The sulphurb ecomes the catalyser under the action of the ul tra-violetl ight .

PRE SSURE CURE .

P RESSURE cure i s the designation covering the severalpatented methods O f vulcanization by heat and sulphur, conducted either in air or an inert gas under pressure . I t i s oneof the recent improvements in rubber shoe manufacture , displacing the ordinary steam-heated dry-ai r vul caniz ing method ,particularly for boots and heavy goods . The method orig i-fnated in the United S tates . The chief advantage of pres surecure for rubber footwear seems to be greater solidity of therubber composition and more perfect contact O f adj acentparts in the structure of the goods due to expul s ion of air bypres sure . E s sential ly thi s resul t i s al so attained by subj ect

VULCAN IZING INGREDI ENTS 63

ing the goods to vacuum or pressure treatment previous tothe ordinary dry-heat curing w ithout pressure .

ELECTRI C VULCAN I ZATI ON .

TH E substitution of electricity for steam is not new, butan improved method O f vulcaniz ing rubber by electric ity hasrecently been patented that , according to the claims , not onlyeff ects a great saving in heat and labor , but in sures a moreuniform cure

'

in l es s time . M etal contacting strips or platesare employed

,through which is passed an electrical current ,that i s maintained for the proper length of t ime' to eff ect acure . B y constructing the heating strip or plate at differentpoints with sections of varying electrical resi stance , the vul

canization of belting, packing , mats , t ires and molded goodsmay be accompli shed .

SULPHUR BATH VULCAN I ZATI ON .

VULCAN I ZATI ON by immersion in a bath of molten sulphuri s adapted for the cure of pure rubber “dipped” article s orthose made of cut sheet . I t i s conducted , at temperaturesvarying from 135 to 160

'

degrees Centigrade,i n a specially

construc ted apparatus in which the melting of the sulphur i seff ected by a direct firing plant . The sulphur vapors areremoved by a powerful exhauster . The vul canized articlesare freed from adhering sulphur by heating in soda solut ion .

VULCAN I Z I NG I NGREDI ENTS .

A MORPHOUS SULPHUR—The fusion of 1 pound of sulphurw i th 4 ounces of Canada bal sam produces what i s known asamorphous sulphur, which i s said to cure rubber so that itwill have no tendency to b loom . The preparation has a verypungent sulphurous O dor. P atented by Dr . W i lhoi t , of New

Y ork .A RTI F I CIAL SULPHURET O F LEAD— There are s everal com

h imations of lead and sulphur which may be produced art ific ial ly . That one containing the most sulphur has a composition of 13 per cent . of sulphur and 86 per cent . of lead . I ts

specific gravity i s about I n color i t i s b lack. The othersulphur compounds of lead have much l es s . sulphur, one containing but 9 per cent . and the other only 4 per cent . What

64 VULCAN I ZING P RO CESSESi s known as hyposulph ite of lead is a mechanical mixtureof the above first named , with a sui tab le percentage of sulphurto eff ect vul canization . I t i s also known in the rubber tradeas “

Eureka compound ,” “burnt hypo ,” and “black hypo .”Thes e compounds when pure— that i s , when free from adulteration— are of great value . They produce goods that are j etb lack and have l ittle odor and are free from bloom . They arereckoned as the safest vul caniz ing agents , as i t i s almos t imposs ib le to burn goods that depend upon their presence forcure . They are us ed in either dry or wet heats .

B ARI UM SULPH IDE i s prepared from heavy spar by mak inga dough of i t with charcoal and oil and subj ecting i t to a whiteheat . Sulphides of the alkaline metal s , potas s ium ,

sodium ,

calc ium ,and barium , will vulc anize rubber , whence the term

“alkal ized rubber.”B ROM I N E .

— A heavy deep red volati le l iquid,possess ing a

most pecul iar and unpleasant odor, and giving off vapors mostirritating to the ai r passages and lungs . I ts very name meansstench . I t has a powerful action upon most organic bodies ,coloring animal matter brown , while i t b leaches coloring mat

ters,dyes , etc . I ts specific gravity i s A piece of sheet

rubber dipped into bromine i s vulcanized instant ly . I t i ssomewhat soluble in alcohol , and very soluble in ether , b isulphide of carbon , chloroform , etc . N ewbrough and F agan fi ledtwo patents in the United S tates for the us e of bromine invulcanization

,both with and without iodine . B y adding toiodine V2 it s weight of bromine , proto-bromide of iodine i sformed

,which i s said to combine with india rubber and pro

duce a hard compound on being exposed 1 hour to a temperature of 250 degrees F . To prevent the forming of an explosivethe iodine and bromine were separately treated with oil ofturpentine to which had been added a quarter of its weight ofsulphuric acid . I t was then m ixed with the gum in the proportion of 2 pounds 11 ounces to every pound of gum . B ro

mine was al so used alone by these inventors , the materialafter molding b eing plunged into the l iquid , and left therelong enough to harden . To prevent the hardening of thematerial whi le in the bath , chloroform or any other so lvent of

CHLORINE— CHLORIDE O F SULP HUR 65

rubber was added in the proportion of 1 part to 9 parts ofbromine ; in other words , the rubber vulcanized in the ai rafter its withdrawal from the l iquid .CHLORI N E .

— Chlorine i s a greenish yellow gas at al l ordinary temperatures . I t has s trong b leaching properties and3 13 0 21 very bad smell and action upon the respiratory passages .Under a pres sure of 127 pounds to the square inch at 60 degrees F .,

chlorine condenses to a yellow liquid, having thespecific gravity of Chlorine cannot , as a rule , destroymineral colors or blacks produced by carbon . H elm claimedthat he was able to produce white hard rubber by incorporating chlorine with the mass .CHLORIDE O F SULPHUR— Sulphur and chlorine form three

compounds , the monochloride , the dichloride , and tetrachloride of sulphur. The sub stance commonly used in the arts i sthe first named or a mixture of the firs t two . I t i s an oilyliquid of the specific gravity and boi l ing at 239 degrees F .

I t has a pungent smell and decomposes on contact with wateror watery vapor . P ure chloride of sulphur i s of an orangeyel low color of great density . I t fumes strongly when exposed to the air

,throws O ff the vapors of hy d rochlor ine , andi s quite poisonous , severely attacking the mucous membranes .

I t i s widely known as the active agent in P arkes ’s cold-curingprocess , where i t i s us ed in connection with b isulph ide of carbon . A common formula for th i s i s chloride of sulphur, 1part by weight

,bisulphide of carbon , 30 to 40 parts by weight ;immers e from 60 to 80 s econds . I n the manufacture O f bal

loons and toy bal ls,the soluti on i s a far weaker one . That

for the outs ide dip i s 10 part s of chloride of sulphur to 100parts b isulphide of carbon , while for the inside i t i s 16 partschloride of sulphur to 100 parts b i sulphide of carbon . Wheni t was common to cure proofed cloth by the cold proces s , i twas done by wetting it s surface with a mixture of 5 to 10parts O f chloride of sulphur, dis solved in 100 parts of b isulph ide of carbon , then running the fab ri c over heated drumsto evaporate the mixture . I n the sulphurizat ion of oil s forrubber sub stitute s chloride of sulphur plays a most importantpart , nearly al l of the amber and white products being pro

66 VULCAN IZING P RO CESSESduced by its use . I t also has a curious eff ect upon bastardgums , giving some of them temporari ly the elasticity andappearance O f high-grade rubber.

GO LDEN SULPHURET O F A NTIMO N Y .— Thi s i s prepared fromblack antimony by boil ing it with caustic soda and sulphur forsome time . The l iquid i s then clarified by fi ltration or sett l ingand the clear part treated with a di lute acid

,preferably muri

atic or sulphuric . A golden yellow precipitate i s formedwhich should be well washed in water , and dried at not toohigh a temperature in a darki sh place . The resul ts of thi soperation wel l carried out are constant and the compos itionshould b e : A ntimony , sulphur

, Golden sulphuretO f antimony heated in a tube wil l give off sulphur which wi lldeposi t on the cool s ides of the tube away from the flame andthe res idue will turn b lack , being indeed the b lack sulphide ofantimony . A ll samples of thi s compound should be tes ted forfree acid , by shaking up a l ittl e of the powder in a test tubewith cold or hot water, and tes ting the water afterwards withsome barium chloride and b lue litmus paper . A white cloudin the firs t place and the reddening of the paper in the secondplace indicate the presence of more or les s free sulphuric acid .Golden sulphuret prepared with muriatic acid wil l not respondto the first test

,but will to the second .

GOLDEN SULPHURET OR A NTI MONY RED (pentasulphide ) i sused more largely than any other form of antimony in rubberwork . I t i s also call ed orange sulphide of antimony

I ts composition i s pentasulphide of antimony with calc ium sulphate carrying free col loidal sulphur . The fol lowingtypical analys i s represents a standard American grade

A ntimony, as pentasulph ideCalc ium sulphateFree sulphurWater of crystal l izationMo istureThe calcium sulphate and water of crystallization are pres

ent as legitimate cons ti tuents and are in no sense adul terants ..Golden antimony may b e made with various percentages

of free sulphur , although the usual standard i s 17 per cent .for rubber work . A s ordinari ly used this allows ampl e sulphur for vulcanization .

68 VULCAN I ZING P RO CESSESing to 320 degrees F remalnlng there 5 m inutes , then dropping rapidly to 250 degrees F . , and continuing for an hour atthat temperature .

LIVER O F SULPHUR— Thi s i s really pentasulph ide of potassium ,and i s obtained by mixing carbonate of potas sium together with sulphur. I t i s cal led l iver of sulphur on account

of it s brown color. A s i t i s qui te volati l e if should be keptin well closed glas s vessel s . The fluid for vulcaniz ing purposes i s a concentrated solution of the pentasulphide , about25 degrees B aume being right for use . To cure with i t theliquid i s brought to the boil ing point in a porcelain ves sel ,the artic les to be vulcanized being immersed in i t . Thi s i sknown as Gerard’s process and i s said‘ to b e inexpens ive andperfectly safe .

M I LK O F SULPHUR— A nother name for what i s ordinari lytermed precipitated sulphur. I t i s fine

,l ight

,and grayish

white in color,but i s often adul terat ed with sulphate of l ime .

I t should be kept in a dry place , as i t has an afli nity formoisture.NA NTUS I i s a vul caniz ing agent and preservative for rub

ber,cons isting of sulphur and paraffin , and in use in E ngland .

I t i s off ered as preventing the superficial cracking of rubberexposed to the atmosphere ; preserving the qual i ty of therubber ; doing away with the poss ib i li ty of acidification in sulphur as ordinari ly used ; and reducing the cost of the mixing.I t i s said to be a special mixture of paraffin and sulphur. 3

P ENTASULPH IDE O F A N TIMON Y . -The chemical name forgolden sulphuret of ant imony (which see ) .

P ROTo-CHLORIDE O F SULPHUR — See Ch loride of Sulphur.SULPH IDE O F LEAD.

— O CC111‘

S native as galena and is one ofthe ores of lead , having a specific gravity of to Commerc ially i t is a b lack powder, of specific gravity I ts composi tion i s per cent . of lead and per cent . of sulphur .Sulphide of lead i s a very us eful b lack pigment , and one thati s used qui te largely in rubber works , as i t i s a good fil ler andas s ist s in vulcanization . I t i s often made from pure whitel ead by very s imple treatment . I t materially ass ist s the res illoncy of P ara compounds .

SULP HUR LOTUM—SULP HUR B ALSAM 69

SULPHUR LOTUM .— 'A name forsub limed sulphur that has

b een washed to remove sulphurous acids , and careful ly dried .SULPH IDE O F Z I N C— Sulphur forms with z inc two sul

phides . O ne of these , the monosulphide , corresponds to z incblende

,which , as found native , i s of various colors , from yel

low to b lack. I ts specific gravity i s from to The otheri s a pentasulphide artificially prepared and occurs in the formof a white powder. Upon ignit ion in the ab sence of ai r thislatter sub stance loses four-fifths of it s sulphur, but the temperature at which thi s takes place i s too high to render i tavai lab le as a source of sulphur of vulcanization in compounding rubber mixtures . W i th a sl ight addition of sulphur it isused in the production of white goods .

SULPHUR occurs in a number of diff erent forms , and undervarious names as brimstone , flowers or flour of sulphur, rol l sulphur, rock sulphur, etc . I ts specific gravity i s to I t

melts at 239 degrees F ., thickens and becomes orange yel low at320 degrees F . ; at 428 degrees i t i s s emi-sol id and red , and oncarrying the heat higher i t becomes browner and boils at788 degrees F . Some of the sulphur now us ed commerciallyi s recovered from alkal i waste ; formerly most O f it came fromS i ci ly, where it i s found native . The American supply nowcomes largely from Loui s iana , where , by the inj ection ofsteam to deep- lying depos its

,the sulphur i s melted and forced

to the surface . I t i s more general ly used in rubber worksthan any other ing redient , and in al l proport ions from 3 percent . up to 100 per cent . of the weight of the rubber . The

ordinary form in which i t i s found in the rubber factory i sin a yellow powder

,known as flowers of sulphur. I t has a

s li ght affinity for moisture , and careful manufacturers keep itcovered from ai r to avoid the formation of sulphurous or sulphur ic acids . Combined with certain oi l s by heat , i t formsthe black sulphur sub sti tutes that are often used in rubbercompounding. Sulphur in the form of rol led brimstone ispulverized , s ifted and used in the place of flowers O f sulphur,in F rance

,and i s equally good and cheaper .

SULPHUR B ALSAM .— A solution of sulphur in “fixed O i ls ,

cons i sting of 2 ounces of flowers of sulphur in 8 Ounces oflinseed oi l , used in proofing compounds .

70 VULCANIZING P RO CESSES

O

VESUVI AN WH ITE — A special vul caniz ing material manufactil red in England, fo’r use i n the manufacture of tenni s bal lsand other goods .

VULCA N I NE.—A n E ngli sh vulcaniz ing preparation , us edfor both steam and dry heat goods . I t occurs ei ther as a white

Or a black powder, depending upon the l ine of goods on whichit i s to be used .VULCOLE .

— A paste furnished in two colors , white andblack, added to certain compounds , prevents blooming. I t

alsohas the quali ty of rendering flowers of sulphur inert ifused in excess , so that 50 to 75 per cent . can be us ed in anOrdinary Soft compound .

The tab le following indicates vulcaniz ing pres sure inpounds per square inch in gage , and corresponding temperatures by the F ahrenhei t s cale :

A ND TEMPERATURESTemperature Pressure

111 in lbs .

F ahren per sq .

he it inch indegrees . gage .

71727374757677

787980

81

82

83

84

8586

8788

8990

91

9293

9495969798

99100

P LANTA TI ON HE VEA A ND O P TIMUM CURE 71

PLANTATI ON HEVEA A ND TH E OPTI MUM CURE .

TH E rel iabi l ity of fine hard P ara from wild Amazoniansources serves as a standard for the preparation of plantationfine as they are both derived from Hevea braziliens is . A greatdeal of sci entific research has been devoted to seeking thecauses of variation in the time required to vulcanize smokedand unsmoked plantation fine to the optimum cure

,by which

i s meant the best physical results attainable from / a givenspecimen of rubber.

Exhaust ive investigations in thi s field have been carriedOn continuous ly for several years in the chemical laboratoryand experimental vulcaniz ing factory of the Department ofA gricul ture , F ederated M alay S tates , by B . J . E aton andJ . Grantham . The detai l s of thi s study have been publi shedat intervals in the “Journal of the Society of Chemical I ndustry ,” London . I t i s suffi cient here to indicate the resul ts bybrief ab stracts and quotation of summari es as given by theauthors .

There i s a marked tendency to look to fine hard P ara asthe standard because manufacturers have had experience withi t extending over many years . That , however, i s the onlyargument in i ts favor. The term uniformity , as applied torubber, means rubber of the same type . Diff erent types ofrubber may vary in mechanical s trength

, but variat ion in vulcaniz ing quali ty i s far more important to the rubber manufacturer . The matter of form and appearance i s of l i tt le consequence to the . manufacturer, al though important to thebroker, buying and sell ing on looks rather than by tes t .

I n vulcaniz ing rubber with sulphur the manufacturer hasrecourse to three methods in securing a given result . He mayvary the amount of sulphur, or the temperature and time ofvulcanization . I n the experimental work of the agricultura ldepartment

,the sulphur and temperature were fixed and the

time varied . I n the original experiments all the rubbers testedgave their best resul ts in 2% to 2% hours . Di ff erent mechani

cal results were obtained by changing the t ime oi cure .Rubber consi sts approximately of 94 per cent . of caout

chouc , 1 per cent . of mineral salts , 2 to 3 per cent . of res ins ,and 2 to 3 per cent . of protein . The ingredient most l iab le

72 VULCAN IZING P RO CESSESto change is the protein , and probab ly some substance derived from thi s act s as an accelerator . Experimental ly i t wasfound that thi s change occurs in the coagulum if left for sixdays before being creped . NO evidence of thi s change canbe detected in the appearance O f the rubber, which in cousequence requires to be tested to ascertain it s vulcaniz ingquality .

A s concerns rubber estate pract ice several factors aff ectvulcanization . These are thickness, i . e.

,amount of serum

removed ; smoking, which retards vulcanization ; the us e offormalin or other preservatives ; amount of acetic acid usedin coagulat ion , and the dilution of the latex . The age of thetree al so affects the proportion of protein and other constitneut s of the latex .

The more uniform methods now adopted on many estate stend to greater uniformity of product ; but variab i li ty i s duechiefly to the diff erence in rubber from diff erent estates .

I n thes e experiments , in preparing the block of pan coagulum , which was left in this form for some days , a really newtype of rubber has been di scovered . I t vulcanizes morerapidly than fine hard P ara and ordinary plantation grades ,which take medium time . O nly eight or nine samples offine hard P ara have been tested so far , but it i s remarkablethat al l vulcanized in about the same time .

I t i s , therefore , natural for the small manufacturer to relyon fine hard P ara . The reason for it s lack of variation isattributable to the uniform method of i ts preparation , andnot because of any intrins ic value of the method . A s i tmay requi re two or three months to prepare a bal l of finehard P ara , any variations in it s quality are averaged .

The formation of the accelerating substance i s b el ieved tobe eff ected by bacteriological action . Rapid- curi ng samplesshow better mechanical test s than those that cure slowly .

Rapid vulcanization el im inates the danger of overheating,and that i s probably the reason for the increase of strength .

Dr . Schidrowitz first pointed out this variabi l i ty i n rateof cure in plantation rubber, of which the experiments at theagricul tural department firs t showed the caus e . I t i s poss ib le

VARIA B I LI TY IN RA TE O F CURE 73

now to prepare a rubber which Wi l l vulcanize correctly at anyparticular t ime

,within certain limits .

Subsequent experiments have been directed to ascertaining the nature of thi s accelerating sub stance and it s b ehav iorunder diff erent treatments , to determine its probabl e constitution . ‘

These effo rts have result ed in the i solation or preparation of a substance or sub stances from the latex s erum towhich acceleration in rate of cure can b e attributed , and evidence has b een O btained of the presence’

of a second substancewhich also has a similar eff ect .

The experimental results confirm the theory that the rateof cure is influenced by the amount of an accelerating agentformed by the decomposition of some consti tuent of the latex,

and that thi s sub stance i s a decomposition product of theprotein or nitrogenous constituents of the latex

,produced

usual ly in the freshly coagulated raw rubber by the action ofmicro—organisms

,which gain acces s to the latex after i t leaves

the tree , or poss ib ly in some cases decomposit ion by chem icalaction . The retarding eff ect of smoking

,on the rate of cure ,

has proved to be a more compl icated prob lem that at firstappeared . The retarding eff ect , though invariab ly Shown byslab , has been found not to be constant in sheet , especiallyin thin sheet . Th i s i s due to the fact that

,in smoking rubber ,

more than one variabl e factor, influencing the rate of cure , i spresent .

I n most of their experiments the authors,E aton and

Grantham , us ed raw rubber in the form of s lab sl ightlypressed

,or unpressed coagulum containing a large percentageof s erum . The latex was coagulated one day about noon , left

in the serum til l ab out 10 A . M . the fol lowing day and thenrolled under a wooden roll ing pin on a sloping tab l e . A ll

samples were eventual ly converted to thin crepe before vulcaniz ing .

CAUSE S O F VARIA B ILITY IN RA TE O F CURE .

The investigation i s in three divis ionsPART I .

— EX PERI MENTAL.P art I emb races a group of experiments for determining

74 VULCAN I ZING P RO CESSESThe time necessary to develop the change In s lab rubber ,causing an increase in rapidity of cure .

The eff ect of antiseptics,heat and cold .

The eff ect of formalin .The eff ect of soaking in running water .

CO N CLUS I ON S UNDER PART I .

1. That the rate of vulcanization of rubber from anygiven latex i s determined by the extent to which a certainchange takes place subsequent to coagulation .

2 . Thi s change i s normal ly l imited to the firs t few daysafter coagulation . The change i s progres s ive and reaches amaximum in “slab .me (i . e.,

coagulum containing a largeproportion of the serum ) in approximately s ix days aftercoagulat ion .

3 . The change can be arrested either partially or completely by the action of formalin , heat , and cold . I t i s alsoarrested by creping shortly after coagulation , which may bedue either to the larger surface exposed or to the more rapiddrying

,or both , combined with the removal of most of the

serum in machining to crepe form .

4 . The complete arrest or inhib ition of the change byformal in (s imilar eff ects have been obtained with other antis eptics ) and by the action of both heat and cold , indicates theformation by biological action of a substance which increasesthe rate of cure of raw rubber

,the decomposi tion being prob

ably of an anaerob ic nature . There i s no evidence that thechange is due to chemical agencies .

I n thi s connection experiments carried out on latex frozenfor several days at 12 to 15 degrees F ., are of considerab leinterest

,s ince by freez ing for thi s period , the rubber no longer

cures rapidly , even if left for a considerab le period afterwardsat 84 degrees F .

"The method of freezing latex to produce rubber has beenpatented in the F ederated M alay S tates . Latex after freezingfor 4 to 5 hours i s coagulated and , on thawing the sol id blockthus formed

,a solid coagulum is formed , whereas latex can be

frozen for a short period and on thawing i s reconvert ed intolatex .]

76 VULCAN I ZING P RO CESSESon the theory that , in the s lab rubbei', decomposition of theprotein or nitrogenous sub stance takes place . A solub le portion is washed out during creping, and the insoluble residue ,or part of it , i s presumably the substance caus ing accelerationin rate of cure in the case of s lab rubbers .

I n view of the vulcanizing results Obtained in P arts I andI I , the authors have analyzed a large number O f their sampleswhich are tabulated below , together with the rate O f curedetermined by the load- s tretch curve method .

I n every case , the amount of nitrogen in a S low-curingrubber, i s about 50 to 100 per cent . greater than the amount ofnitrogen contained in a fast-Curing s lab rubber, the amountof nitrogen b eing determined on al l samples after conversi onto crepe and drying.

O n the other hand , the amount of nitrogen in samples ofrubber prepared by the evaporation of thin layers of latex,or by pouring out the latex into thin layers , after addition ofacid coagulant

,and al lowing the thin sheets thus obtained to

dry rapidly,i s high , and amount s in some cases to per cent .

Such sampl es are rapid-curing, although the percentage ofnitrogen indicates that no decomposit ion of the protein orni trogenous constituents of the rubber has taken place , thefactor deciding rapidity of cure being apparently , i n this case,

VARIA B I LI TY IN RA TE O F CURE 77

the unknown substance present in the evaporated serum afterremoval of the maj or portion of the protein .

SUM MARY .l . The experiments and results of P art I show that one

factor which caus es variabi li ty in respect of rate of cure inplantation P ara rubber i s produced during the first s ix daysafter coagulation and that the change which takes place inthe coagulum i s progress ive during this period , while afterthi s period

,no further change , under ordinary conditions

,

takes place .2. The action of antiseptics , such as formalin , as wel l as

heat and cold,are al so shown to inhibi t thi s change

,while

soaking of the fresh coagulum in running water considerab lyretards the rate of cure .

3 . The action of formal in is al so shown to be partly,

though not to any great extent, an action on the acceleratingagent after it s formation .

4. Experiments on ' the cold storage of freshly coagulatedrubber Show that while the change which produces rapidity ofcure i s inhib ited as long as the coagulum remains in coldstorage

,if the rubber i s removed again and allowed to remain ,

without machining, for a further period (13 days or poss ib lyles s ) at ordinary atmospheric temperatures (about 85 degreesF . in the F ederated M alay States ) , rapidity of cure i s againbrought about .

5. A ll‘

the experiments of P art I suggest that the changewhich produces rapidity of cure in the rubber i s caus ed bybiologi cal agencies

,that is to say

,micro- organisms entering

the latex after col lection and remaining in the coagulum , andthat the change i s probab ly a decomposi tion of the protein ornitrogenous substances present in the coagulum , producingan accelerating agent which i s a decompos it ion product of theproteins .

6 . The experiments of P art I I , on the slow-curing rubbers of various proteins and nitrogenous substances , and theirdecomposi tion products , including the proteins from the latexserum decomposed by suitab le methods after separation fromthe serum , confirm the conclus ions from the experimental

78 VULCAN I ZING P RO CESSESevidence contained in P art I , and Shoiv that the original protein s have li tt l e or no eff ect under the condit ions employed ,while the decomposed proteins have a marked eff ect .

7. Experiments with undecomposed evaporated serum ,

after separation of the proteins coagulated by heat , suggestthe presence of a second factor which accelerates the rate ofcure, and i s due to some sub stance originally present in thelatex.

8. I n the case of the author’s so- called s lab rubbers,

possib ly both factors are responsib le for the acceleration ofthe rate of cure , and it would appear that the second factor maybe responsib le for the actual superior tensi le propert ie s of therubber. Some evidence to thi s eff ect i s contained in the comparatively poor qual ity of the rubbers to which the proteindecomposition product has been added , in which the secondfactor has been removed , and al so in the good qual ity in thecase of the evaporated latex samples and the rubber to whichthe evaporated serum has been added . F urther experimentsare , however, necessary to confirm this .

9. Experiments with evaporated latex,which contain s

al l the serum constituents and i s dri ed with suffi cient rapidityto prevent decomposition of the protein s , al so confirm thepresence of thi s s econd factor .

10. The nitrogen figures given in P art I I I sti l l furtherconfirm the decomposition theory , that i s to say , the production of some sub stance from the protein which accelerates therate of cure

,the nitrogenous portion which becomes solub le in

water and is removed on creping being non- essential . The

high nitrogen content , on the other hand , in rapidly curingrubbers produced by evaporat ion of the latex , without decompos ition of the protein , again confirms the evidence obtainedas to a second factor which i s probably of a non-nitrogenousnature .

11. These experiments and resul ts,

al so Show why it hasnot been poss ibl e hitherto to connect the nitrogen content ofa rubber with its rate of cure , s ince a rapidly curing rubbermay have either a low or high nitrogen content , and indicatehow previous workers have gone astray , or not gone suffi

VA RI A B I LI TY I N RA TE O F CURE 79

c iently far in their investigations , in connection with the protein or nitrogenous constituents of latex and rubber.12 . M any other experiments on nearly samples of

rubber al l confirm the above results and conclus ions .13 . A further investigation i s now being made as to the

exact nature of the protein decomposition product , wh ichaccelerates the rate of cure , and as to the nature of the secondfactor responsib le for acceleration , together with the numeroussubs idiary factors which influence the rate of cure , a numberof which have already been investigated .

The authors have since found that the protein left inSheet of average thicknes s can be decomposed and so producea more rapidly curing sheet rubber by S imply roll ing up thesheets after machining in order to retain suffi cient moisturecontent for the bacterial decomposit ion . Thi s demonstratesthat the rapidity of cure of the so-call ed slab rubber i s largelydue to the decomposition of protein nO

‘

mfi' al ly retained by

the rubber, even after rolli ng to sheet form . These resultsal so show the importance of the rate of drying during earlystages , as a factor in the preparation of sheet rubber , i n orderto have a uniform rate of cure.

CHA P TER V.

ORGA NI C A ND INORGA N I C A CCELERATO RS .

TH E following summary represents an eff ort to clas sifythe principal nitrogen-bearing accelerators i n a logical manner, and to record concis ely thei r characteri stics and efl

‘icacyas described by R . Di tmar and trans lated into F rench for “LeCaoutchouc et l a Gutta-P ercha ,” by Georges Noyer ; A ndrewH . K ing in “M etal lurgical and Chem ical Engineering” ; S . JP eachey and Douglas F . Twiss in “

The I ndia Rubber Journal” and others .Whatever may be the future of synthetic rubber

,the ln

vestigations in connection with i t led to the di scovery oforganic accelerators which have revolut ionized,s everal l ines

of rubber manufacture . I t was found that synthetic rubbercould not be vulcanized without the presence of certainorganic catalyzers to faci l i tate the union of rubber and rubberlike sub stances with sulphur, and when al l natural rubber wassub stituted the increased rapidity of vul canization was trulyremarkab le . The diffi cul ty, as for a t ime with plantationrubbers , appears to have been the absence of certain so- calledimpurit i es found evenly di stributed throughout P ara rubbercoagulated by the Amazon method . These natural catalyzersof rubber latex are beli eved to b e decomposition products andrelated to the proteins . I t i s certain that all organic accelerators yet known are nitrogen-b earing and many have aminogroups , so that the function of nitrogen appears to b eimportant .

M anufacturers who had been us ing the O ld , well-knownmineral accelerators began to experiment with these, neworganic catalyzers and found that they could doub le theiroutput without expensive increase O f steam pres sure ordanger of impairing the product by high temperature . Thoseengaged in the production of cheap molded goods discovered

80

ORGAN I C A CCELERA TORS 81

that by employing both high temperatures and catalyzerstheir increased output would take care of ‘

overhead .

While thi s most important recent development in rubberchemistry i s s ti l l in its infancy , there is already considerabl egeneralization and a goodly amount of definite facts on whichto bui ld . I t i s thought that , unlike the mineral acceleratorswhich undergo no chemical change during vulcanizat ion , anorganic catalyzer unites with one of the reacting sub stancesand forms an unstab le compound which then reacts with theother substance . M eanwhi le the catalyzer i s set free and theentire proces s i s repeated . F rom a mechanical standpoint acatalyzer i s most conveniently mixed when a solid capabl eof being very finely pulverized . A high boi ling point i s es sent ial to prevent vaporiz ing during vulcanization and conse

quent spongy appearance,known as “blowing .”

The most important organic accelerators are as follows °A nil ine oil. flB Dimethy l A trimethy leneamine.

Carbon b isulphide add ition products Tr imethy leneamme.

with B enzy lamme.

A ni l ine. N ltroso d imethylanil ine.

Dipeny lthiourea or th iocarbanil P iper id ine and der ivativeside. P iperid ine or aminopentane.

Dimethylani l ine. M ethyl p iper id ine.

‘ Tetrahydropyrrole Quino l ine and der ivativesDimethy lamlne. Quinol ine,

fiflDlmethy l X methyl tr lmethy Quinol ine sulphate or quinol inelene amine. sulphonic ac id .

Ammon ium compounds Hydroxy quinol ine.

Ammonium borate. Quinosol .A ldehyde ammon ia. O x iquinol ine.Quarternary ammonium bases . O x iquinol ine sulphonic ac id .

Am ino Compounds : O X IQUIHO IIUC Sulphide.

A ccelerene or paranitroso d ime M i s cel laneousthy lanil ine. A nthraquinone.

P ara-

phenylenediamine. A ntipyr ine.

) Tetramethylened iamine. Naphthylamine.

H examethylene-tetram ine or hex Urea der ivat ives .

amethy leneamine or formin. A ni l ides .

Sod ium amide. Formani l ide.

Naphthy lenediamine. Thioformanilide.

Several of these accelerators are covered by patents andmus t b e purchased through certain dealers who are preparedto quote to the consumer prices inclus ive of the li cense feeof the patent owners .

82 ORGAN I C AND INORGAN I C A CCELERA TORSThe catalyzers in question are piperidine and . methyl pip

erid ine, tetramethylenediamine , hexamethylene-tetramine , thiocarbanil ide, and ani l ine hydrochloride . The firs t three of theseare not made in the United S tates at present .

AN I LI NE .

A niline—This material , described in Chapfer X I , has beenextens ively employed as an accelerator in rubber work for anurnber of years , particularly in the manufacture of automobile t ires and tubes .

To obviate the poisonous eff ects of ani line i t i s e ss entialto protect the workmen by the use of waterproof outer garments , such as rubber shoes , gloves and aprons to preventthe absorption of the liquid by contact with the skin . In

addition i t i s al so neces sary to remove thoroughly and rapidly al l ani line fumes aris ing from the warm rubber duringthe mil ling and calendering and generally by venti lation toprovide an abundance of fresh air in the work rooms .

CARBO N B I SULPH IDE ADDITI ON PRODUCTS .

With A niline.-Diphenylthiourea , or thiocarbanil ide, is oneof the earl ies t known organic accelerators . I t takes the form

of large colorles s tablets melting at 154 degrees C., and is a

very effici ent catalyzer,particularly for qui ck-curing stocks ,

because i t does its work at the very beginning of vul canization . The proportions used vary from V.» to 3 per cent .With Dimethy laniline.

— Cited by Ditmar and King.With Tetrahydropy rrole.

—Known as pyrrolidin in Ger

many. Ci ted by Ditmar and King.With Dimethy lamine.

— This substance gives an active addition product . W i th P ara , 100 per cent . sulphur and the addition of 1 per cent . of the compound of carbon b isulphide anddimethylamine vulcanization takes place completely wi th 15minutes’ cure at 135 degrees C . (German patentWith 1318 Dimethy l x methy l Trimenthy lene Amine—Cited

by Ditmar.AMMON I UM COMPOUNDS .

Ammonium B orate.—This noticeably eff ects the cure , but

the fact has only sc ientific interest , according to Ditma r.

84 ORGA N I C AND IN ORGA N I C A CCELERA TORSpos sesses several characteri st ics in us e that are of g reat value .Goods vulcanized in its presence Show somewhat greater tensi l e strength , probab ly due to the dimini shed degree O f depolymer ization poss ib le in so short a period of heating. Vulcanization s tops when the goods are taken from the pan or press

,so they suff er littl e deterioration in storage,tests

~demonstrat

ing this now covering a period of two years. Sulphuring-upmay also be entirely prevented by its use, though at the sacrifice of acceleration . The quanti ty of sulphur may be reducedto 3 or 3% per cent. per cent . of accelerene i s then addedand the mixing cured in the ordinary manner. A s employedfor thi s purpose the catalyzer faci l i tates a complete combination of rubber and sulphur, with the resul t that l it tle or noneof the latter remains in the rubber.

P ara-pheny lenediamine.—This very poisonous catalyzermelts at 140 degrees C.

, sub limes without decompos ition at267 degrees C., i s readily solub le in alcohol and ether , andmoderately so in water. I n B ayer Co .’s German patentNo. January 1, 1914, i t is s tated that thi s acceleratorgives good sati sfaction with synthetic rubber, 100 parts isoprene rubber having been cured completely upon being mixedwith 10 parts sulphur, 2 parts para-phenylenediamine and being heated in a press for 15 minutes

,at 45 pounds steam pres

sure .Tetramethy lenediamine.

— Known also as putrescine, this isa natural product of protein decomposi tion formed during theputrefaction of animal matter such as fish . I t i s producedchemical ly by B ayer Co .Hexamethy lene

- tetramine.—Known also as Hexamethy

leneamine and F ormin. T his accelerator is largely used . It

comes as a fine white crystall ine powder. The U. S . P . gradei s free of moisture whi le the so-cal led technical grade usual lyContains about two and one-half per cent . of water .

I t i s very soluble in water and as it vaporizes freely inthe Operations of mixing and calendering it occasions cons iderab le trouble in the form of a rash or eruption on the skin ,parti cularly on exposed surfaces moi stened with perspiration .The us e of gloves , and otherwise protecting exposed portionso f the body

,minimizes the annoyance .


M is cellaneous Amines — O ther amino compounds cited byKing as of lessei' importance yet having s ome acceleratingpower include : sodium amide (rapid acceleration according toDi tmar ) ; naphthy lened iamine (rapid accelerat ion accordingto Ditmar ) tr imethy leneamine, benzylamine (rapid acceleration according to Di tmar ) ; flfl dimethyl A tr imethy lenea

mine , and nitroso dimethylanil ine .P I PERIDI NE A ND DERIVATIVES

P iperidine or Aminopentane.—A l iquid mi scible in water in

all proportions,having a specific gravi ty of .881 at 0 degrees

C., boiling at degrees C., and smelling like pepper andammonia . Thi s , the prototype of the more recently discoveredorganic catalyzers

,was brought out and patented by B ayer

Co. in 1912, for use in the manufacture o f synthetic rubber, buti t s extraordinary value as an accelerator in connection withnatural rubber for both hard and soft rubber articles Soonovershadowed it s ori ginal purpose . A mixture of 100 partsP ara and 10 parts sulphur that requi res an hour to cure at 53pounds steam pres sure

,may be cured perfectly with only 15

minutes’ heating by the addition of V2 part of piperidine . The

product Obtained from this compound contains about per cent .of combined sulphur . P iperidine may also be used for produc ing hard rubber by adding 25 per cent . sulphur. (Germanpatent No.

M ethy l P iper idine— This active catalyzer boils at 107 degrees C .QUI N OLI NE A ND DERIVATIVES .

Q,uinoline.—While this is a good accelerator

,its derivatives ,

sulphate and quinosol , are more frequently used becaus e ofthe ease of mixing. Quinol ine has a specific gravity ofat 20 degree s C. ; i t boi ls at 240 degrees .C. , and i s solub le inalcohol and ether

, but only sparingly SO in water . I ts odori s disagreeable and penetrating ; it s taste , bitter and acrid ;and on exposure to moist air i t i s converted to the hydrate .A s an accelerator the amount used i s 2 or 3 per cent . Quinoline does not exert accelerating power, according to Ditmar.

86 ORGA NI C AND IN ORGA N I C A CCELERA TORSQuinoline S ulphate.

— A lso known as quinoline sulphonicacid . A n exce l lent accelerator yielding good- looking wel lvulcanized rubber. King suggests that the potas sium salt ofthi s acid might give better resul t s .Hydroxy Quinoline.

—This derivative , which ought to provea valuab le accelerator, takes the form of pri smatic needlesmelting at 76 degrees C . and boiling at degrees C . under752 mm . pres sure . A lthough readily soluble in alcohol andvolati l e with steam it i s only sparingly soluble in cold water.

Quinosol.—This accelerator takes the form of sulphur yellow needles soluble in both alcohol and water . I t i s manufactured by F ri sch

,of H amburg, Germany , and mixes eas i ly

with rubber compounds before vulcanization . I n a mixtureof P eruvian rubber , 12 ki lograms ; white substitute , 19 ki lograms ; Kaolin (China clay ) , 2 kilograms ; chalk, 5 kilograms ,and sulphur, ki lograms , the accelerating eff ect , accordingto Ditmar, i s not great , but quinosol acts qui te diff erentlywhen mixed with litharge and crude rubber free of substitute ,the combined effect b eing greater than the sum of the eff ectsof each employed alone . Thi s fact i s of great importance torubber footwear manufacturers who use 'mixtures containinglitharge exclus ively

,as they can cut the period of vulcaniza

tion in half by us ing 2 to 3 per cent . of quinosol .Ox iquinoline .

— Cited by Ditmar.Oxiquinoline Sulphonic A cid — Gives good acceleration but

very porous rubber, according to Di tmar.Oxiquinoline S ulphide.

— Th is i s a satis factory but too activeaccelerator . I t can be us ed with al l sorts of compounds because it answers al l the needs of the industry . I n tests conducted by Ditmar in collaboration with the Japanese chemis tN awa-Naami , a mixture containing P eruvian rubber , 40 kilograms ; brown rubber subst itute , 10 ki lograms ; paraffi n , 5ki lograms ; chalk , 41 ki lograms ; and sulphur, 4 ki lograms ,required 2 hours’ heating at a pressure of 4 ‘ atmospheres (56pounds ) . W i th ox iquinol ine sulphide the mixture was vul-icanized i n 50 minutes . W i th quinoline sulphate 75 minute swere requi red . Tests Of accelerated and unaccelerated products showed the same breaking point , but the elongation of


the accelerated product was found to have been reduced onehalf

M I SCELLAN EOUS .

A nthraquinone.—Recommended in 3 to 5 per cent . strengthin batches containing rubber substitute . I n a typical mixture

containing rubber substitute s i t reduces the duration of vulcanization from 2 hours to one-half hour .

A ntipy rine .—A cts l ike anthraquinone . (Ditmar.)

Naphthy lamine.—A cts l ike anthraquinone.

Urea—This and such derivatives as guanidine have beenfound useful . (Ki ng )

F ormanilide.—Many patents cover the anilides , such as

formanil ide .Thioformanilide.

— Cited by King.A lbumen— The direct addition of proteins to rubber, asdescribed by W . E s ch in German patent No . Novem

ber 22 ,1912, pres ents an interest ing poss ibi l ity . The protein ,

usual ly egg albumen , 15 parts , i s mixed with 2 parts hydratedl ime or magnesium hydroxide to form a paste . Low gradesO f rubber, when mixed with thi s paste , dried , sheeted andsmoked to render the albumen insoluble , are considerab lyimproved thereby.

Magnes ia.—Marckwald and F rank claim that

1. M agnes ia aff ects vulcanization only by forming Intermediate products which accel erate the combinations oi sul

phur with rubber .2 . O wing to decomposit ion of the chloride (l eft inthrough inefficient washing) by exposure to the ai r, and alsoduring vulcanization , magnes ium chloride and sulphate form

undesirab le contents in cold vul canized goods .I n cold cure with chloride of sulphur vapor sulphur in

the mixing has no more immediate influence than any otherfiller— although a later action may perhaps b e expected in awarm , l ight warehous e .

The following accelerat ing preparations are patented byDr . D. F . TwissQuicklime slaked with a solution o f sodium or potassium

hydroxide and the resul ting soda or potash l ime employed as

88 ORGAN I C AND IN ORGA N I C A CCELERA TORSa fine powder . Suitab le proportions are found to be ten partsof quick l ime to three parts of sodium hydroxide or four partsof potass ium hydroxide . B y using one per cent . of such apowder in a rubber mixing

,the alka l i hydroxide can be more

evenly di stributed than if used alone .A nother method i s to use the caustic alkal i in conjunct ion with an organic s olvent such as glycerol . I f thi s i s

heated to about 175 degrees C . to expel superfluous water,the hydroxide can be di s solved and alkal i glyceroxide O btained .P otas sium hydroxide i s found somewhat preferab le for thi smethod and also for the quickl ime one . O ne part of potass ium hydroxide may be used with four parts by weight ofglycerol , although the proportions may be widely varied .O ne or two per cent . of such a solution may be mixed intorubber uniformly and there i s no tendency to produce poros ity of the rubber ; but the vulcanization process i s greatlyaccelerated , the eff ect being comparab le with that of thestronges t organic accelerators . I t i s al so noteworthy thatthe actual quanti ty of alkal i approximates closely to the onehalf per cent . recommended for the most eff ective organicaccelerators and that with a rubbersulphur mixing the resul ting vulcanized rubber in both cases posses ses the same clear,dark , almost semi- transparent appearance .

A mixture of rubber with five per cent . of the solut ion ,when cured for 90 minutes at 40 pounds pres sure , undergoescomplete vulcanization

,practical ly no sulphur remaining un

combined . O ther organic compounds may be employed forthe solution of the alkali , such as glycol . A s to aging ofsamples vulcanized in the presence of the alkal i solution ofglycerol

,after a lapse of three years s ince vulcanization a

certain weakening was observed , but no greater than in similar mix ing s containing other accel erators .

The fol lowing are trade designations of secret compoundsused as accelerators , based on ingredients mentioned in thischapter — A ccelemal , A nnex , A nvico, Dry A niline , Duplex , Excellerex,M . C . C.

,P aradin , Tensilite, Velocite, Velosan, Vitami

nex , Vulcacit.

CHA P TER VI .

F ILLERS A ND INGREDIENTS USED I N RUB B ER

COM P OUNDS .

I NDIA RUBBER i s compounded for two reasons,the firs t

being to reduce the cost without destroying the us efulness O fthe gum, the s econd being to impart quali ti es pos sessed bya great vari ety of mineral, vegetab le , and even animal substances .

A GALMATOLITE .—A si l icate of aluminum resembling soap

stone . I t has no advantages over talc, si l i cate of magnesia ,or soapstone in rubber use . I ts spec ific gravity i s about

A LUM I NA .— The oxide of alum inum and a ch i ef constituent of c lay . I ts specific gravity i s O rdinari ly speaking, i t i s a very inert sub stance , insoluble , and not readilyattacked by acids . I t i s b est known in the arts under theforms O f corundum , emery , etc . A s obtained chemical ly it i sa fine white gl i stening powder

,harsh and dry to the touch .

E aton’s formula for the use of oxide of aluminum in makingwh i te rubber was ‘ india rubber 40 per cent ., oxide of aluminum 55 per cent . and sulphur 5 per cent .

A LUM I N ITE .—A wh i te clay containing a large percentage

of aluminum (about 30 per cent . ) and a certain amount ofs i l i ca . I ts specific gravity is low,and its fusing point

degrees F .

A LUM I N UM F LAKE .— A natural product in the form of a

white powder, free from grit , with a specific gravi ty ofI t i s a remarkable heat res i stant , i s inert in compounds , andtoughens them . I t i s a partial sub s titute for zinc oxide, bothfor color and strength .

A LUM I NUM O X IDE— See A lumina .A LUNDUM .

— A patented abrasive material made fromoxide of aluminum or bauxite .

A MPH I B,

OLI N E .— A German earth . When wetted and

dried , i t wil l not absorb water again . Specific grav i ty aboutI t i s used in waterproofing , the product b eing non

90 F ILLERS IN DRY M I X ING

inflammab le . I t i s mixed with gelati ine or S ize , no rubberbeing used : 34 parts amphibol ine , 9 parts gelatine , 2 partschrome alum ,

2 parts ammonium sulphate, 53 parts water .

A N HYDRITE .— The water-free form of sulphate of lime or

gypsum , white in color and crystall ine in form . I ts specificgravi ty i s I t i s formed artificial ly by heating gypsumso as to drive off all it s water . Gypsum that has been overheated in the preparation O f plaster of P aris and that haslost its abil i ty to “s et” i s pure anhydrite . I t i s used as a fil lerin rubber compounding ins tead of whiting or P ari s white .

A NTI MON Y .—See Golden Sulphuret of A ntimony , B lackA ntimony , and Kermes .

A NTI MONY O X IDE—There are real ly three of these oxides .The trioxide , one most useful i n the arts , i s a snow-whitepowder O f the specific gravity of I t may be Obtainedby treating stibnite or, better still , powdered antimony metal withnitric acid

,in a current o f air sufli cient to carry O ff the copious

fumes arising during the Operation , or by treating the chloride o fantimony with cold water for several days . ' A mixture o f thetrioxide with a small percentage O f the insoluble peroxide . maybe obtained by melting antimony in a cast iron retort fitted withnozzles, through which air may be blown to agitate the meltedmetal . Dense white fumes arise, which may be condensed insuitable chambers into a snow-white powder. This is used incoloring dental vulcanite.

A RGI LLACEOUS RED SHALE .—A shale .that has a large

amount of c lay in it i s termed argillaceous , and the sub stancementioned in the heading may be briefly termed clay tintedred wi th oxide of i ron . The analys i s of argil laceous clayShows : alum ina 39 ,

si l ica 46,water 13 , i ron , magnesia , and

lime 2 . I t was the bas i s of a well-known oil- res ist ing compound that for years baffled imitation . Specific gravity

A RSEN I C.— A white britt le metal , with a specific gravity

of or according to its form . A l so a popular term forthe oxide of arsenic

,sometimes called the white arsenic , which

is a heavy white powder of the Specific gravi ty I t i ss l ightly solub le in cold water and to the extent of 10 per cent .in hot water . There are several coloring matters formed from

92 F I LLERS IN DRY M I X ING

Canad ian . I tal ian.

S i l icaMagnes iaWater of hydrationA lum inaP rotoxide of i ron .75Soda .68P otash , etc . .22 15Sulphur ic ac id traces 31

The longest fiber i s pos sessed by the I tali an,which i s

sometimes 3 feet in length . The Canadian ranges from 3 to 6inches in length , but i t i s finer, more flexib le

,and more eas ily

s eparated than the I tal ian . The mineral divides its elf naturally into three c lasses : the first , coarse , brittle , very plentiful ,and cheap ; the second , posses sing wel l-defined fibers of abrownish-yel low color, fragil e , and containing many foreignbodies ; the thi rd , with pure white s i lky fibers which can b ewoven into texti les . A notab le use to which asbestos hasbeen put i s in the production of packing and brake linings .I ts low heat conductivi ty renders i t particularly useful insteam packings

,both for cylinder work and for j oints

,whil e

it s incombustib i l ity has long caused i t to be used for fireproofing purposes . There are fibers formed of serpentine rockwhich are much used as a sub sti tute for genuine asb estos , andanswer nearly as well , being, however, Shorter in fiber andsomewhat l es s durab le .

A TM IDO .— A snow-white fil ler of low specific gravity

,free

from organic matter and indiff erent to acids . Used in smal lprOportions ,

'

iS said to increas e both s trength and resi li ency insoft rubber goods . Used in large proportions , i t makes a veryhard compound , said to resi st superheated steam . O f Germanorigin .

‘

A TM O ID.—A very l ight white earthy matter of E nglish

origin . A nalys is proves i t to be an almost pure s il ica— quitec lose

,i n fact

,to infusorial earth . Specific gravity

B ARIUM CARBONATE .—See Carbonate of B arium .

B ARYTES .—A heavy white mineral that in commerce takes

the form of a fine white or gray powder. I t i s obtained bygrinding the mineral heavy spar, or by chemical means frombarium chloride . I ts specific gravity i s I t occurs in commerce under the names “permanent white and “

b lanc fixe .

”

B A S O F OR—DLUE LEAD 93

The artificial ly prepared substance i s to be preferred to thefinely ground mineral , on account o f its less crystalline form .

The commercial article should always be examined to determine i ts freedom from acid impuri ti es . B arytes i s chiefly usedas an adul terant for white lead and paints . Thus , Venice whitecontains equal parts of sulphate of barytes and white l ead ;Hamburg white, 2 parts to 2 parts of white lead ; and Dutch white ,3 parts to 1 part O f white lead . I t i s wholly inert when used asan ingredient in rubber compounding, increases the res i l iencyof rubber, and i s amake-weight.

B A SO F OR.— A trade designation for a specially prec ipi

tated barium sulphate or “blanc fixe . Used as an inert fi l l erand pigment . See B arytes .

B LACK A NTIMONY . —A black powder obtained by grindingstibnit e or antimony ore . I t i s a sulphide of the metal and i smet with more or less pure, as it is O ften prepared from a highg rade ore . The Sulphur contained in i t i s unavailab le forvulcaniz ing purposes , and if used in compounding it i s necessary to add a suffi ciency of sulphur to vulcanize . I n the pures tform

,black antimony contain s about 28 per cent . of sulphur

and 72 per cent . of antimony . I t i s insolub le in water, buti s di s solved by muriatic acid or by caustic alkalies . F romits solution in alkal i a fine b rown-red powder may be obtainedby treatment with a dilute acid

,and th i s powder, known as

kermes,has the same chemical composi tion as that mentioned

above . I ts specific gravity is I t was formerly used sometimes as a fil ler

,as i t was beli eved to gi ve a soft effect in

molded goods . I t has been almost whol ly displaced,however ,

by cheaper and better ingredi ents .B LACK LEAD— See P lumbago .B LAN C F I XE OR P ERMAN ENT WH I TE — A rtificial barium

sulphate , special ly prepared by precipitation from solutionsof native barytes . There are several methods giving variations in product adapting it to specific purposes . The spec ific gravity is The grain is extremely fine and amorphons . I t i s part icularly valuab le as a fil ler and i s said toenhance the tensil e s trength of rubber . See B arytes .

B LUE LEAD—Where zinc ores are found in combinationwith galena

,or natural sulphide of l ead , the two are often


smelted together wi th raw coal and s laked l ime,producing

a fume called b lue pov’

vder , which i s sold under the name ofblue lead . I t i s an excellent fi l ler, but i s not as good assub limed lead , for exampl e , as i t does not impart enoughresi li ency to rubber. I ts chief merit i s it s cheapnes s . A veryfine quali ty of b lue lead , containing cons iderabl e lead oxide ,i s now on the market, but thi s mus t not be confused witheither of the two low-grade articles mentioned in th ese paragraphs . Thi s b lue lead i s of exceeding fineness

,and gives a

pecul iarly soft finish to the rubber. Us ed in the place ofl itharge

,it materially ass is ts in the cure

,and produces a fine

b lack . A s i t has a high specific gravi ty,i t often displaces

barytes . B lue lead i s al so a name given to an artificial aluminous substance occurring either as a loose powder or in aconcrete form , colored b lue by means of some kind of b luedye—ani line or logwood— which does not contain lead .

B ON E A SH —See Calcium P hosphate .BONEBLACK .— See Charcoal (A nimal ) .B UCARAM A NGUI NA .

—A transparent amber-colored , incombustib le material

,found near B ucaramanga , Colombia. I t i s

somewhat s imilar to asb es tos , for which i t has been mentionedas a sub st itute in the manufacture of packings .

B URNT UMBER—A n earth contain ing a large amount ofi ron oxide of a dark-brown rust color. A s mined , it i s cal ledraw umber

,and the product obtained by calcining it i s knownas burnt umber . I t was formerly used in brown packings ,

and to a certain extent , in maroon goods .CALAM I N E .

— A n ore of the metal zinc,and a carbonate of

zinc . O rdinary calam ine , which i s a s il icate of the meta l , hasa specific gravity of to and is little us ed in the arts .Nob le calamine , or native carbonate of zinc , i s a gray or grayish yel low to brown powder, according to its priority . Its

specific gravity i s to I ts nature i s earthy , and heathas no action upon it . A l i ttle of it i s said to toughen softcompounds .CALCI UM CARBONATE .

—Very fam i l iar under the nativeform of l imestone

,marb le , or chalk . See Whi ting.


being inert and strongly coherent . In packings it has been largelyused, and also in compounds for wagon covers and tarpaul insbe fore reclaimed rubber came largely into use. It has also beenused in cements for card clothing.CHALK .— A white, soft, somewhat gritty substance , consi st

ing chiefly of carbonate of lime . I t i s made up of myriads ofvery small shells o f marine animals long extinct . Its nature i searthy ; that is to say, it is not easily aff ected by ordinary bodies .A cids disengage carbonic acid gas f rom it . I ts Specific gravityis I f heated to a red heat , carbonic acid gas escapes andquicklime is left behind . See Whiting .CHARCOAL (AN I MAL ) .

— A nimal charcoal is made frombones distilled out of contact with ai r and has the property, ina high degree, of absorbing Odors and soluble coloring matters .I t i s O ften’used , there fore, in deodorizing rubber goods, andexperimentally by chemi sts for filtering gutta-percha dissolvedin bisulphide of carbon, where a perfectly clear product i sdesired . I ts use i s advised by F orster in gutta-percha compounds, and by Warne , Jaques , and others for packings to withstand heat . I ts specific gravity is aboutCHARCOAL (VEGETABLE ) .

— This is a popular term for thecoal produced by the charring O f wood . There are many materials which are really charcoals

,such as animal charcoal just

quoted, carbon , coke , graphite , and wood charcoal . A ll of theseare practically the same in their pure states , being almost whollycarbon . W ood charcoal— that which i s meant in rubber compounding by vegetab le charcoal— cons is ts of carbon , hydrogenand Oxygen, the last two being in the proportion to form water.It i s black and brittle, insoluble in water, infusible , and nonvolatile in the most intense heat . I t has the power of condensing gases and destroying odors . Charcoal may or may not bea bad conductor of heat and a good conductor o f electricity,these properties depending upon the wood from which it is made.Technically

,i t is divided into hard wood charcoal and soft wood

charcoal . I ts composition at ordinary temperatures is about asfollows : carbon 85 per cent ., water 12 per cent ., ash 3 per cent.Specific gravity (powdered ) to I t i s used in rubbercompounding in certain vulcanite varnishes and in certain insulated wi re compounds . F or the latter use, willow charcoal

CHINA CLA Y— CORKis preferable , as it is a decided non-conductor. It has also beenused in sponge rubber, with the idea that it acts as a preservative in a compound which is very likely to be short- l ived . Mac

intosh used large quantities of ground charcoal in place o flampblack in some of his compounds . A F rench substitute forvulcanite paints or lvuers i s made of 10 pounds O f bitumen , 15parts of charcoal , and a little linseed oil , mixed by heating.CH I NA CLAY.— See Kaolin .CoM P o.

—A name for a composition used in rubber manufacture in the United S tates years ago , but not in use now .

The name , however, cl ings to two compounds sold by anEngl i sh chemical house for use i n rubber work. They are ofa secret nature . NO . 1 i s us ed in the manufacture of oi l-resi sting va lves and in tub ing for chemical factories , in the proportion of 30 pounds of compo to 10 pounds of rubber. NO . 2 i sused for soles for tennis Shoes and in mechanical goods , in theproportion O f 25 pounds O f compo

‘

to 10 pounds O f rubber.CORK i s the bark of th7 cork oak , native of Southern

Europe and Northern A frica . The chief suppli es come fromSpain and P ortugal . Cork is the basi s of the fine black knownas Spanish black , which i s made by burning the refus e i n closeves sels . I n granulated or powdered form ,

cork has longbeen a favorite ingredient in rubber compounding. Not thatit i s used in any such measure as whiting or barytes

,but many

mill s have used it,and a few in large proportions . Used in

connect ion with india rubber and gutta-percha , i t has b een thesubj ect of about fifty patents . I ts largest use

,perhaps , was in

the manufacture of kamptul i con,where india rubber i s used

as a binding material,and in linoleum ,

where oxidized oi l s areused in place of rubber. I t was al so us ed in what was knownas leather rubber, in which palm oil distillate, a little indiarubb er, and a good deal of granulated cork were used . A t

one time i t was also compounded with rubber and made upinto a waterproof felt for hats . I t al so went into compoundsto res ist heat , into cricket bal l s , and into golf ball s , where i twas compounded with gutta-percha and enough metal fi l ingswere added to gi ve the neces sary weight . A rubber blanketused in special manufacture also had its surface covered withgranulated cork as an ab sorbent material . I n some cases the


cork was charred and roasted to remove what resinous mattermight b e in i t, while in others resinous matter was removedby boil ing in alcohol . I n i t s usual form cork has a specificgravity of F ine grinding eliminates much of the contained air with proportionate ri se in specific gravity .CORNWALL CLAY .— See Kaolin .CORUNDUM .

—A mineral which i s nearly pure alumina , yetof great specific gravity , and of exceeding hardness , beinginferior, in this respect , only to the diamond . Emery (whichsee ) i s a variety of Corundum . Specific gravity

DIATOMACEOUS EARTH .—See I nfusorial E arth .

E LECTRI C F I N I SH .— See F arina .

EMERY .— The average compos ition O f emery may be takenas alumina 82, oxide O f i ron 10, S il ica 6, l ime I ts specificgravity is about to 4 . I t i s prepared by breaking the stoneat first into lumps about the S ize of a hen’s egg, then runningit through stamps , and crushing it to powder. I t i s then s iftedto various degrees of finenes s , and graded according to themeshes of the s i eve . Emery i s next in hardnes s to diamonddust and crystal line corundum , and it i s used chiefly as anabrading agent . P rior to the invention of vul cani te , emerywheels were made by heating clay and emery in suitablemolds , thus vitri fying them like common earthenware . In

rubb er mi l ls i t i s chiefly used in the manufacture of what areknown as vulcanite emery wheels . I t i s al so used in grindingand sharpening compounds

,as hones and strops . (See also

A lumina and Corundum . ) A certain amount of i t al so givesthe desired surface to rubber b lackboards .

F ARI NA . —Thi s is sometimes used in small quantities inunusual mixture s as a compound , but has l ittl e value , as thereare many better substitutes for it . A practical use for it , however

,i s the brushing of a rubber surface with i t b efore vul

canization,when it i s neces sary to have printing or stamping

done upon that surface afterwards . F arina i s made largely ofpotatoes , another name for it being potato s tarch . The process consists simply of crushing, si fting, washing, bleaching, andgrinding

,which is repeated three times , and each time the starch

granule s separate and are col lected . I t has a specific gravity


to for ordinary compositions . Generally speak ing, flour O fglass may be considered an inert substance under ordinary conditions , though the softer kinds are attacked even by boilingwater. I t was used by Newton and Wray in insulated wirecompounds, and has also been used in certain packings .

F LOUR O F P HO SPHATE — See Calcium P hosphate .F OSS I L F ARI NA

,also called mountain milk, is ' an earth physi

cally similar to infusorial earth . I t is obtained from China andconsists of sil ica 50V2 , alumina 2672 , magnesia 9, water andorganic matter 13 , with traces o f l ime and oxide of i ron . I t hasbeen used in rubber compounding for the production of packingsand semi-hard valves .

F OSS I L MEAL OR F O SS I L F LOUR — See I nfusorial Earth .F REN CH CHALK. —This 18 ground and si fted talc, forming a

white,greasy- feeling powder. Its chemical composition is

hydrated Silicate of magnesia , the water being chemically combined . Its specific gravity is See Talc .

F ULLER’S EARTH .— A kind of clay. I t i s a greenish or brown

ish earthy, somewhat greasy- feeling substance, having a shining streak when rubbed . I ts composition is : sil ica 70, oxideiron alumina lime 6, combined water 16, magnesia trace ,phosphoric acid trace , salt 2 , alkalies trace. F uller’s earth isfound in extensive deposits in England, where its annual consumption at one time exceeded tons , chiefly in woolenmanufacture for full ing cloth . Its specific gravity is fromto I t is used in rubber compounding for about the samepurposes as infusorial earth , and is also used in the manufac

ture of rubber type .GOLD O X IDE — A s a matter of curios ity i t may be noted

that this is the most costly ingredient suggested for rubber compounding. I t occurs in two forms— the protoxide, a dark greenor bluish violet powder, and the teroxide, a brown powder. Theuse of the protoxide was patented by N inck. F or dental vulcanite it is doubtful i f either form of the Oxide could be used , eveni f

,

the price were so low as to bring it within reach . A notherformula call s for the mechanical admixture O f gold leaf .

GRAPH I TE — See P lumbago .GYPSUM .

~ —See Calcium Sulphate .

IN F US ORIA L EARTH—KERMES

I N F USORI AL EA RTH . - I t i s known also as diatomaceousearth , Tripoli, fossil meal , mountain flour and kieselguhr. Thisis obtained usually from deposits at the bottom of inland waters ,and consists O f the minute sil iceous remains of infusoria ormicroscopical animals . The largest deposits , in the form of afine white or pinkish powder, are found in Cali fornia , NovaScotia, and in Germany. This earth is a wonderful non- conductor O f heat , and, in connection with asbestos , is used in themanufacture o f boiler coverings . I t i s used also in small proportions in various rubber compounds , where it increases bothstrength and resiliency, though i f used in excess it makes a veryhard compound . The best grades are wholly f ree f rom vegetablematter

,are nearly pure s i l ica , and perfectly indiff erent to cor

rosive substances . Under the name of diatomaceous silica it isused in a formula for elastic valve packing. This packing isdescribed as practically indestructible in steam or water, O ils,acids, etc. Specific gravity, to

IRON P y RITEs .— A natural sulphuret of i ron , about spe

cific gravity, commonly of a bright, brass-yellow color ; a veryplenti ful mineral O ften mistaken for gold . I t i s used in themanufacture of sulphuric acid, while sulphur is also Obtainedfrom it by sublimation . I t was used by Warne , F anshaw, andothers , in the manufacture o f packings to resist a high degreeof heat . The sulphur m l ron pyrites has also been used invulcanization . Warne, in one O f his heat- resisting packings,patented the use of iron pyrites , and , in the compound that hegives as an example, leaves out the whole or a portion of thesulphur usually employed .

KAOLI N .

—A white clay largely used in the manufacture ofporcelain and to a degree in rubber compounds . I t is a hydratedsilicate O f alumina . Specific gravity

KERM E s .— A brownish- red form of sulphide O f antimony,

artificially prepared by boiling in carbonate O f soda . I f le ft toitsel f the solution will partly deposit a very fine powder ofkermes , while the clear solution may be further treated with aweak acid to Obtain the remainder. Kerrnes will not vulcanizerubber without the addition of sulphur. I ts specific gravity i sabout I ts composition is 28 per cent. sulphur and 72 percent . antimony . I t i s rarely used in rubber compoupd ing .

102 F ILLERS I N DRY M IX ING

KI ESE LGUHR.— See Infusorial Earth .

LEAD A CETATE OR SUGAR O F LEAD— A white poisonouspowder solub le in water and alcohol . I n its crystal l ine formit contains about 7 per cent . of water of crystal l ization

,which

i s eas i ly driven off at a temperature of, say , 80 degrees to 100degrees F . I ts specific g ravity i s : crystal l ized , water- free

,

I ts use in s emi-hard composition was patented by bothGoodyear and P ayen . I ndia rubber dis solved in oil

,to which

has been added acetate of l ead , i s used to fi l l the pores ofcertain leathers so that the “fi l l ing shal l not come through .I t i s al so us ed in certain varnishes in connection with guttapercha .

LEAD CARBONATE — See White Lead .LEAD O X IDE — See M inium and Litharge .LEAD O XYCHLORIDE .

— There are several oxy chlorides oflead . Their specific gravity may be taken at The sub

stance once known as Turner’s yellow and another known asCarsel yellow were both of this composition . More recently awhite compound has been prepared , which , from its coveringpower, has been used largely as a paint . Tarpaul in compoundsconsisting of india rubber

,coal tar, and pitch are treated with

oxy chloride'

of lead for surface drying, in lieu O f vulcanization .LEAD P EROXIDE .

—The highest oxide of lead— a darkbrown powder with a specific gravity of about I t i seas ily decomposed

,and from this characteri st ic it has a strong

oxidiz ing action . Exposed to sunlight or to heat,i t yields

oxygen and passes into the lower oxide known as red lead .I ts oxidiz ing properti es make it a ques tionable ingredient incompounding rubber , although certain formula s call for i tspres ence .

LEAD SULPHATE .— A white powder of the specific grav

ity of insolub le in water, but readi ly soluble in causticalkal ie s . I n Cooley’s formula for artificial leather, wh ich hasgutta-percha for a base , i t I S used in connection with dextrine ,magnesia

,and cotton dust .

LI ME— The Oxide O f the metal calcium . I t is commonlyknown in two states

,viz . : quicklime , which is the pure oxide , and

slaked lime,which is the hydrated Oxide mixed with some car


cured by taking them out of the mixing room entirely,and

putting them to work on vul canizers , part icularly where theyopen and handle the goods from the fini shed heat

,the theory

being that the sulphur fumes neutral ize the eff ects of thelead . P ossibly there i s a grain of wisdom in thi s

,for the

oldfashioned treatment for l ead poisoning was sulphur bath sand the drinking of water ac iduated with sulphuric acid or theacid sulphate of magnesia . Li tharge is not only a valuablefi l ler for rubber, but has the facul ty of hastening vul canizationin a marked degree . I n other words , it i s an accelerator . A ll

dry heat goods depend upon it,and in mold work and general

mechanical goods it i s used whenever pos s ib le . O f course ,i t i s general ly avai lab le for dark or b lack eff ect s only

LITH ARGRITE .—~A sub sti tute for litharge

,made of a mix

ture of pulverized and calcined magnesia and oxide of lead .LITHOPONE .

—See Colors .MAGN ES I A . —A calcined white dry powder which , with

water, forms a hard , compact mass like marble . I ts specificgravity is I t i s earthy in i ts nature , having no tas te ,but producing a sens e of drynes s in the mouth , owing to i tsabsorption of moisture . I t i s frequently called calcined magnes ia from the method of preparation by burning magnesiaalba . I ts us e in rubber i s to increase i ts toughness and resiliency , which it does to a marked degree when us ed in moderation . M agnesia i s als o used in the production of compoundsl ike balenite , it s use in hard rubb er compounds being to increase resili ency as wel l as hardnes s . A very smal l quantityof i t i s al so used in compounds for in sulated wire , where iti s said to increas e the insulating qualiti es of rubber . Carbonate of magnes ia occrir s native in the m ineral magnesiteand

,i n connection with carbonate of lime , as dolomite .There exist two kinds O f calcined magnesia : the heavy andthe light calcined . Heavy calcined magnesia is produced by cal

e in ing heavy carbonate of magnes ia , which carbonate i s wonby p rec ipitation of hot magnesia solut ions by hot solutions ofsoda . The l ight calcined magnesia i s produced by calciningthe l ight carbonate of magnesia

,and this l ight carbonate i s the

precipitation product of magnesia solut ion together with soda

MANGANESE P EROX IDE—M I CA 105

solutions , both careful ly cooled . The diff erence between kindsof calcined magnesia concerns on ly the structure

,so that l ight

calcined magnes ia in a dry state seems to have a very b ig volume, but i f the included air i s expell ed , the b ig volume cannothave the expected eff ect

,i f l ight calcined magnesia i s knealed

together with india rubber on the mixing rol lers . The vulcanization of india rubber can easi ly be accelerated by additionof calcined magnes ia . Such an addition i s often necessarywith soft rubbers in Open steam- cured compound s . Rubberswi th a high amount O f resins , such as Guayule , Cameroons ,A s sam

, B orneo , etc ., usually give better result s if compounded with appropriate additions O f calcined magnesia .

MANGANESE P EROXIDE—A nother name ‘ifor black Oxideof manganese , which is a b lack powder having a specific gravity of I t i s not readi ly acted on in ordinary ways , beingunchanged by heat short of bright red . I t i s insolub le in theordi nary hydrocarbon solvents . Solvent naphtha was treatedwith peroxide of manganese by Humphry to free it fromwater.

O xides of manganese have a destructive effect on rubber,and b lacks that contain thi s , as they sometimes do , are to beavoided . Manganese is used in connection with pitch , turpentine

,and gutta-percha for making B randt’s cement .MARBLE F LOUR .

—This i s the finely ground chips of whitemarble

,composed almost whol ly of carbonate of l ime . I t

i s a heavy i nert powder us ed in rubber compounding as asub stitute for barytes . I t has also been used to some extent inhard rubber , and in the manufacture of hones . Specific gravity to

MASS I COT.— A monoxide of l ead (l ighter yel low than litharge ) . Specific gravity A higher degree of oxidation

turns this into a product cal led m inium or red lead . I t i soften used in rubber compounds

,acting practically like lith

arge.M I CA i s the name given to a group of complex s il icates

containing aluminum and potassium ,generally with magnesi

um, but rarely with lime . Their specific gravity ranges fromto whi le their color vari es greatly . Ground mica

106 F I LLERS IN DRY M I X ING0

i s s imply one or other of these micas reduced to powder . I t i sus ed in rubber compounding chiefly for insulating purposes .I t i s handled as a cement , compounded with rubber , and cutwith benzine , or may be mixed dry on the grinder . I t i s alsoused in fireproof coverings in connection with rubber

,and it

i s said that for a s emi-hard resul t that i s to come in contactwith hot water, rubber and mica form the best compound .M i ca in a s tate O f a very fine powder i s also known as “cat’sgold” or “cat’s si lver.”

M I NERAL WOO L .— P roduced by sending blasts O f steamthrough molten slag, which reduces the fluid metal to a fibersimilar to the fused glass that is spun into glass silk. Naturalmineral wool , such as i s found in the Hawaiian I slands , i s verybrittle, but the artificial has considerable toughness . I t i s alsoknown as slag wool , or sil icate cotton . I t appears in light fleecymasses , and at a distance looks like fine cotton batting. I t i s verycheap

,but i s easily aff ected by weak acids , and should be kept

away from a moist atmosphere . I t has not been largely used inrubber work as yet , but Lascelles-Scott strongly advis es i tsuse , giving as reasons its cheapness and its physical fitness .The sulphides present in it al so ass i s t in vulcanization .

M I N I UM .— See Red Lead .

MOUNTAI N F LOUR— See Infusorial E arth .O RANGE M I N ERAL— A red lead made from carbonate of

lead , while red lead is made from litharge . A s a general rule , itcontains some lead carbonate . I t differs f rom red lead in color,in that it is more orange red, and more brill iant . The reasonfor this diff erence is that it i s less crystalline , its particles beingmuch finer than those of red lead . The pigment is also morebulky and much smoother. I t i s used in finer grades o f darkrubber, to assist the cure and impart resiliency. I ts specific gravity is

O SSEI N .

-A light powder made from specially treated bone .Said not to be aff ected by acids . I s not aff ected by heat and is nothygroscopic . P reparation patented in England by J . F . Hunter.

P AGODITE .—A mineral resembling steatite or soapstone . I ts

name comes from its having been used in the E ast as a materialfor carving miniature temples or pagodas from, as it is soft

10'

s F I LLERS IN DRY M I X ING

of sulphur . A s cold- cure gums are of l ittle value as insulatorsh is invent ion i s of doubtful value . He al so made a prepara».

tion of india rubber , res in and tal low , and shoddy, to b eapp l i ed in a fluid state where gas came in contact with rubber,adding phosphorus after his solut ion was fini shed,to prevent

decomposition O f the rubber. Duvivier also treated guttapercha with sulph ide of phosphorus , claiming that he gotan elast ic resul t

,but al lowing that his compound was dam

aged by acid vapors , to neutraliz e which action he mixedcarbonate of soda with it . A n anti- foul ing preparati on ofE ngli sh origin was also made of gutta-percha

,turpentine

,and

a l ittle phosphorus .P I PE CLAY .—A pecul iar kind of clay containing neither

i ron , sand , nor carbonate of l ime . I t i s b eautiful ly white , retaining its wh itenes s when burnt . I ts specific gravity i s 2 toI t was used by Mayall in combination with gutta- percha , indiarubb er

,z inc , shel lac , and resin for insulating tape, and by

A ustin G. Day to ab sorb gases during vulcanization .P LASTER O F P AR I S — Thi s i s prepared by calcining gypsum

or sulphate of l ime . I ts properti es of hardening when madeinto a paste with water are wel l known . I t i s used sometimesin stead of lime in compounding and al so for making trialmolds for rubber work . I t was used in O ld - fashioned dryheat compounds to prevent b l istering . Specific gravitySee A nhydrite .

P LUMBAGI N E .— A dark-colored pigment manufactured in

E ngland and sold to rubber manufacturers for the productionof valves . B y its use the rubber is vulcanized and goods madewhich are said to resist successfully the action of cheap lnbricants . O ne pound of plumbagine is used to two pounds ofrubben

P LUM B AGo.— This sometimes i s cal led b lack l ead , though

having no relation to l ead ; i t i s al so called graphite . I ts specific gravity is to Its color is black and shiny. I t consi sts . chiefly of carbon

,but contains more or les s a lumina ,

S i l i ca , lime , i ron , etc ., varying from 1 to 47 per cent . , but notchem i cally combined . B lack lead i s a perfect conductor ofelectricity . I t i s more incombustibl e than most ingredient s

P ORTLAND CEMENT— P OWDERED COA L 109

used in rubber compounding, and i s capable of withstandinggreat heat . I t i s us ed in the rubber indus try , chiefly in themanufacture of what are known as graphite or plumbago packings . I t i s a wholly inert substance

,safe to us e i n connection

with any compounds , and . i s not aff ected by heat or acids,

alkalies,or corrosive substances . I t i s useful also in certain

poli shing compositi ons made with india rubber as a base .A lmost al l German asbes tos cements contain a proportion offinely powdered graphite .

P ORTLAND CEME NT was first obtained by burning the mudfound at the mouths of several large rivers in Europe with aproportion of c lay and l ime . I ts compos ition 15 somewhatcomplex

,containing : l ime 55 to 63 per cent ., si li cic acid 23 to

26 per cent . , alumina 5 to 9 per cent ., and oxide of . iron 2 to6 per cent ., together with magnes ia , potash , soda , sulphate oflime

,clay

,or sand in various small proportions

,according to

the mode of manufacture . I ts specific gravity i sI ts value as a cement depends upon the interaction of the limeand the si l icic acid . I n compounding it would have no chemical eff ect s upon rubber, but might of its elf b ecome much hardened and thus cause mechanical injury to goods in which ithas been introduced . A s i t occurs commercial ly , i t i s a gri ttypowder of a gray-b rown or yel low-brown color . I ts only useas far as known in rubber is where it i s mixed with tar oiland waste rubber to j oint pipes contain ing fluids .

P OWDERED COAL.— Coa1 consists chiefly O f carbon, and isuniversally regarded as being of vegetable origin . Various coalsdiffer widely in their composition and characters , running fromthe softest kinds O f earths to compact and solid bodies like parrotcoal , which is so compact and sol id that it has been made intoboxes , inkstands , and other articles which resemble j et . The

average specimen O f coal analysis i s : carbon hydrogenoxygen Some curious compounds of india rubber and coalhave been formed . O ne , for instance, was a mixture in whichtwo pounds O f waste india rubber in a cheap solvent was mixedwith nearly a ton of powdered coal (specific gravitywhich contained some clay and peat , the use being for an artificial fuel ; another use was in the production of hard rubber.


P UM I CE .— A light, porous, ashy stone, specific gravity

the product O f volcanic action , its st ructure being that of amass of porous glass . I ts composition is a mixture o f silicatesof aluminum, magnesia, calcium, i ron , potassium,

and sodium,

varying with the particular lava whence it had its origin . I ts

action on india rubber will be quite inappreciable,chemically

speaking, but its mechanical action will be that of a ‘ sharp cut

ting powder. Ground fine, it i s used in the manufacture oferasive rubber, and i s also used compounded with the rubberin the manufacture of hones . Recent patents call for its use incertain semi-hard compounds , its presence being said greatly toincrease their toughness . M ixed with lard oil to a thick paste

,

this has been used for polishing india rubber.It i s particularly valuable for use in the dry-heat cure o f

such articles as water-bags and bottles . The goods filled, beddedand covered with fine pumice powder are evenly cured withoutdiscoloration or change of color. In this respect pumice issuperior to talc for the purpose, and the goods are more easilywashed clean .

P UZZOLANA .— A porous lava found near Naples, usedchiefly

,when mixed with ordinary lime , in forming hydraul ic

cement. Compounded with marine glue , it i s used as a varnishfor preserving metal li c articl es from corrosion .

RED CHALK . —A rtificially deposited chalk colored by anysuitable pigment— usually one of the red oxides of iron . See

Chalk.RED LEAD—A n oxide of the metal , which is also known as

minium . P repared from pure massicot or from white lead . “

Its

specific gravity is to A scarlet crystalline granular powder

,of rather strong coloring powers . A S a colorant in rubber

work it would be unavailable, since the sulphur necessary to vulcanize would render it more or less black, owing to the formationof sulphide O f lead . I t i s sometimes used , however, in place oflitharge . I t i s also used in “hot” cements O f gutta-percha andfor varni shes such as those made of india rubber, l inseed oil ,etc .

,for covering the b ack s of m irrors . See M inium ,

M assicot ,and O range M ineral .


STARCH .— A vegetab le sub stance al l i ed closely to ce llu

l os e . I t occurs in regular lumps composed of granules whichhave a definite character, according to the variety of the plantfrom which they were derived . When d ry it s specific gravityi s Commercial s tarch contains usually about 18 per cent .of water and , i f kept in a damp place , will ab sorb 33 per cent .of water . I t was much us ed formerly on solarized work . Torrefied starch is obtained by roasting the common form

,and i s

us ed in artificial leather compounds .SUBLI MED LEAD— A white lead known as sub limed lead i s

used very largely in rubber manufacture . I t i s a fine whiteamorphous powder and imparts a decided toughness to rubbercompounds . I t acts both as a fi l l er and chemicall y . I ts

pecul iar velvety fineness makes it m ix intimately with therubber, and gives a very fine finish , showing no shiny crystalson the surface . The oxide of lead in the sublimed lead willa lso b ind free sulphur in the rubber. The amorphous stateof the sub limed lead makes the action of the lead oxide in thismuch more eff ective than the action of l itharge , and the resul tis a very smooth , lively, j et—black rubber. Specific gravity

SUGAR O F LEAD— See Lead A cetate .TALC OR F RENCH TALC i s a mineral allied to mica . I t is

composed enti rely of s i l ica and magnesia,in the proportions

of 67 to 73 of s il ica,30 to 35 of magnesia

,and 2 to 6 of water .

Specific gravity I ts colors are s ilvery white , greeni shwhite , and green . Talc s late i s more like steati te and i s usedfor s imilar purposes . F rench talc i s used very largely inrubber factories in al l li nes of work for preventing surfacesfrom sticking together

,during either manipul ation or vul

canization. I t i s als o us ed commonly for dusting molds toprevent the gum from sticking to the metal and extensively tobury white goods and keep them in shape during vulcanization . I t i s used sometimes in compounding, but any greatamount of i t produces a stony eff ect . I t makes , however , anexcellent semi -hard packing . I t i s us ed further in compoundsfor soft poli shing

,with india rubber as a binding material .

TALITE .—A white earthy material used in general rubber

compounding. I t i s al li ed to diatomaceous earth , presumably ,

TIN OX IDE— WHI TE LEAD 113

and has the same usage . ’ I ts analys is shows : M oistures i l ica sesquioxide of iron alumina oxide of manganese trace , potash trace , combined water and organi c matter(by igni tion ) lo s s and undetermined —total 100 .

T I N O X IDE—The form most frequently used in the art sis the dioxide . This is a white water- free powder, of the specificgravity O f insoluble in acids and such solvents as naphtha ,petroleum, etc. It i s in fusible

,except at a very high temperature,

tasteless and inodorous . F rench oxide of tin is a.

carefully prepared and purified form of the dioxide . I t i s rarely used inrubber work, although N ewton recommends it for a basic ing redient in rubber type . The other oxides O f tin are at presentmerely o f chemical interest.

TR I POLI . —See I nfusorial E arth and Rotten S tone .TYRE-LITH .

— A t rade designation for col loidal barium sul

phate. See B lanc F ixe .WHEAT F LOUR i s used in making matrices for rubber stamp

work, and sometimes as a compounding material in india rubber,though this is not to be advised , as the flour is apt to sour. A

standard low grade of wheat flour known as “red dog is particularly suited to the purpose O f dusting the skim coating of woollinings , because, owing to its pecul iar texture, i t is easily removable by a wash of thin cement in the making-up process anddoes not impair the adhesion to another rubbe r surface .

A large and important use for it has been in the dusting ofblack goods , Such as rubber coats , so as to keep them from sticking together, should they accidentally touch during the dry heatof vulcanization . Wheat flour is preferable to almost anythingelse, for the reason that it washes O ff after vulcanization , without leaving any trace in color or stain . It is used on the goodsknown as dul l finished .”WH ITE LEAD.

—This is a mixture of hydrated oxide andcarbonate O f lead and is a heavy white powder. It is unstablein color, however, as sulphur compounds , especially in thegaseous forms , easily attack it and blacken it by reason of theformation of sulphide of l ead . I ts specific gravity i sSometimes it is adulterated with lead sulphate, chalk, carbonate,or sulphate of baryta , or pipe clay. The simplest test for the


purity of, white lead is to heat it in a thin glass vessel with somevery dilute pure nitric acid ; i f pure it will dissolve completely.I f chalk be present it also will pass into the solution , in whichit may be detected by the addition of caustic potash , throwingit down as a white cloud. The best white lead is made by theold- fashioned Dutch process, which consists O f packing themetallic lead , cast in the form of buckles -to present a large surface for corrosion , in covered earthen pots , in the bottom ofwhich is placed acetic acid . The pots , thus prepared , are stackedand buried in a ma ss of spent tan bark to conserve the heatcaused by the reaction of the volatile acid on the metal . The

original “triple compound , patented by Goodyear, consisted ofindia rubber, sulphur and white lead .WH ITI NG OR CHALK

,as i t is O ften called , i s carbonate of

l ime . I t i s a white earthy material o f the specific gravity ofto I t i s made f rom English chalk

,which is crushed ,

floated , and run through a filtering process , and dried in cakesmade in varying degrees of fineness by a system of dry grinding and bolting. Where whiting i s kiln-dried hastily, or underextreme heat, it is apt to become calcined , which gives it a hard ,gritty feeling. A ir-dried whiting i s considered the best . Whiting is in reality a purified form O f carbonate of calcium, of avery soft or flocculent quality. The finest grades are known as“gilders’” and “extra gilders . I t i s used more generally inrubber compounding than any other material

,except sulphur.

Used moderately, it increases the resiliency of rubber, but addsto the hardness . I t does not , however, produce the stony eff ectthat many ingredients give . The molds used in rubber- stampmaking are composed of whiting, wheat flour

,glue, and carbolic

acid . Whiting is l iable to absorb considerable quantities ofwater f rom the air. It i s customary in many mills

,therefore

,

to keep it in large bins that not only are covered but have steampipes in the lower portions to drive out any moisture from thematerial .WI THERI TE .

-See Carbonate o f B arium .

ZI N C O XIDE — See Colors .ZI N C SULPHATE OR WH I TE VI TRI OL . —The crystals contain

about 44 per cent . water of crystall ization . Specific gravityZI N C SULPH IDE .

- See Colors .


matters are powdered fossi l i ron- stone, W i scons in mineral ,coke ashes , S tourbridge clay , powdered granite , salt , powdered l ithographic stones , powdered oyster shel ls , powderedschist ; and in metals , steel , and al l other common metal bor

ings , fil ings , and turnings . These latter have been incorporated in packings as a rul e . O ne packing ln part icular,which

has had a world-wide reputation , was heavi ly compoundedwith bras s fi l ings .

The deodorization of rubber, and the neutral ization eitherof the smell of the rubber or it s solvent , has b rought out alsoa curious l ine O f ingredients . Musk , for exampl e , has beenus ed to di sgui s e the earthy O dor of gutta-percha . A l coholicinfusions of sage-tea

,lavender, and verbena have been used

in fine goods , while in powdered form ,ginger root

,birch

,

orri s root , sassafras , marshmal low root , sandal wood , andother sweet- smelling ingredients have been incorporated . The

l eaf of the mint has also been mingled with copperas,and

placed in dry heaters , while a more expensive proces s was thatpursued by H i l l , who pas sed a current of hot air over perfumes and into the heaters . I t mus t not b e imag ined that theideas expres sed in the foregoing are unworthy of the cons idc ration of those who make ordinary cheap mechanical goods ,for certain of these ingredients are us ed today in mechanica lmixtures to overcome the O dors O f A frican rubbers . E s sential O i ls and gums are al so used for the same purposes , thedescriptions of which wil l b e found under thei r properdepartments .

M edical sc ience has also added its l is t of ingredients torubber compounding, chiefly in the l ine of adhesive plas ters ,where ingredients l ike dry mustard , menthol , capsicum ,

belladonna and a great variety of other medicaments are incorporated w i th the rubber .

CHA P TER VII.

SUB STITUTES F O R INDIA RUBB ER, NATURA L

A ND ARTI F I CIAL.

RUBBER SUBSTITUTES, as a rule , are made from oxidizedoi l s . Those used most general ly are made from linseed , rapeseed , cottonseed , mustard , peanut , or corn oi ls , acted on eitherby ch loride of sulphur or by sulphur boi led with the oil at ahigh temperature . Sub stitute s have been known over fiftyyears

,and have been made the subj ect s of many patents , but

only within the last twenty-five years have they come into generaluse. The fact that Europeans were unable at first to get theresults w ith reclaimed rubber that were secured in the UnitedStates , led them to go further in thei r experiments with OxidizedO ils and to exploit their uses more thoroughly. The substituteson the market to-day are , as a rul e , white , brown , and black .They are O ften of the same specific gravity as pure india rubber,SO that thei r presence cannot be detected in rubber compoundsby spec ific gravity tests . Substitutes of this type are easilyanalyzed and the results o f such analyses are of value to rubbermanufacturers . The table on the next page, containing analyses of typical substitutes, i s adapted from Dr. Robert Henriques .

*

I t would be a mistake to suppose that rubber substitutesare of no value , for they '

possess certain very distinct advantages not found in simple mineral adulterants nor possessed bythe bituminous products now in use. Their value, of course, iswhere they cheapen stock without seriously injuring its durability or changing its texture . Where substitutes are compounded with rubber they are used in smal l quantities, sometimesOnly 5 per cent . being added , and rarely is more than 25 perc ent. to be found in good compound .

* “Journal of the S ociety of Chemical I ndustry , 1904, pag e 47.

Q

117

120 SUB STI TUTES F OR RUB B ER

A RTI F I CI AL E LATERITE .— Made from liquid bitumen by ln

corporating with it vegetable O ils , such as cottonseed oil , palmO il , rapeseed O il , etc . The product is treated with the aid of heatand pressure, with chloride of sulphur, saltpeter, and sulphur,which produces an oxidization of the fatty substances . The

result i s an elastic rubber—l ike or leathery mass , which is soft ,spongy ,

and gluey. This gum is said to be far more elastic thanthe best samples of mineral rubber, and is use ful for waterproofing and insulation . P atented by W. B rierly, in England .

A RTI F I CIAL GUTTA-PERCHA . —A F rench compound made of50 parts copal , 15 parts sulphur, 30 parts turpentine , and 60parts petroleum . Whil e mixing the heat reaches 100 degrees .

C. ; i t is then cooled to 35 degrees C . Then there i s added asolution of 3 parts caseine

,in weak ammonia , and a littl e

methylene , and reheated to 120 degrees C . I t i s then boi ledw i th a 15 or 20 per cent . solut ion of tannin , and 15 partsammonia . A fter several hours’ boil ing it i s washed and cooled .

A SB ESTON IT.—A n asbestos product manufactured in England under a secret process , for use as steam or hot-water

packing.A STRI CTUM .

—A compound to be us ed in damp places ,cons ist ing of pulped cotton 15 pounds , pitch 25 pounds ,asphalt 20 pounds , ground granit e rock 20 pounds , bitumen5 pounds , resin 10 pounds , coal tar 12 pounds , and mastic 5pounds

B ELLEDI N’S P ROCE SS F OR LEATHER I MPREGNATI ON .

—H idesare treated in alkal ine soluti ons and immersed in a bath ofrubber solution .

B ORCH ERDT’S compound for doll s’ heads consi sts of 5

pounds glue , 10 pounds sugar, 2% pounds glycerine , 3 poundsP erry’s white .

B LACK GERMAN SUBSTITUTE — M ade of boi led l inseed oi land sulphur, together with res inate of l ime . Thi s gum i ss imi lar to adamanta,

and has been practical ly driven out ofthe market by lighter sub stitutes .

B LANDITE .— A n artificial india rubber invented by Dr . A .

L. B landy, of London . I t i s fairly elastic , stretching to abouttwice i t s l ength

,and returning readi ly . I t i s very pliab le and

CA OUTCHENE— CHI CLE SUB STI TUTE 121

does not Show signs of cracking when bent . I t i s vulcanizedlike ordinary rubber, and can be molded into any form des ired .Coated on cloth , i t s trongly resembles l eather. I t i s waterproof

,and i s used for gas tubing , mats , etc . I n it s crude

form , i t i s a l iquid mass resembling molasses . Dr . B landy’s

patent describes the compound as made preferably of linseedO il which has been reduced by oxidation ; then 10 per cent . ofbi sulphide of carbon , to which has been added 10 per cent . ofchloride of sulphur, i s mingled with the oil , and the mixturebrought by gentle heating to the desired consi stency . Trinidad asphalt , cleansed and reduced to powder, i s combinedunder the heat in the proportion of 3 parts to 1 of oi l . Caremust b e taken to avoid fire in heating. These proportions aregradually b rought , by heat and sti rring, to a l iquid or thinstate , and when in thi s condit ion i t mus t b e poured upon awet , cold surface , and thus cast into sheets , convenl ent forsubsequent mixings .

CA OUTCH ENE .— A F rench substitute consi sting of 100 parts

sunflowerseed Oil,25 parts chloride of sulphur , and exposed to

air ten days , when it becomes yellow and elastic. To this isadded mates ite, a M adagascar gum, and then i soprene i sadded .

CA OUTCH ITE .—Vulcanized rubber exposed to heat (250

degrees F .) for several days and devulcanized and recoveredby thi s means alone ,CARROL GUM .

— A well-known sulphur oil sub stitute usedin the United S tates . I n smell i t has al l of the characteri stic sof the sulphurized oi l products . I t i s produced usually ingranular form ,

and i s very black.CEREAL RUBBER—Wheat treated with ptyalin . The inven

tion of W i l l iam Threnfal l Carr, of E ngland . I t i s a glueyproduct which

,after i t comes from the so-cal led vulcanizing

press , i s said to be both plastic and waterproof .CH I CLE ‘ SUB STITUTE .

— A special ly prepared cottonseed oi lsub stitute . Said to be very largely used by manufacturers ofchewing gum. See Gum-carbo .CHRI STIA GUM .

—A n Engli sh sub stitute for gutta-perchaor india rubber

,used as a surgi cal dressing . I t i s said to be

I

C


composed of hemp fibers , so treated as to be impervious toboth alcohol and water. Di eterich analyzed a sample of theproduct , and said that the fibers were sulphite wood pulp , andthat the coating was made from chrome gelatine treated withglycerine , or the wel l-known compound of glue , glycerine ,and b ichromate of potas sium .

CON -CURRENT RUBBER— I nvention of Jul ius Nagel, O f New

Y ork . A s ecret compound , the bas i s O f which i s l inseed oi land res ins .

CORKA LI N E i s made of glue , glycerine , ground cork , andchromic and tannic acids . I t i s of English derivation and isus ed as a substi tute in mat work.CORK LEATHER—A F rench invention composed of thin

sheets of cork, covered on both s ides with an extremely thinindia rubber skin , and of a textil e fabric out s ide . I t i s verylight

,i s a good insulator against heat , and i s waterproof.CORN O I L SUBSTITUTE—A sulphuri zed oi l sub stitute s imi

lar to that made from oxidized l inseed or rapeseed oi l s , manufactured from corn or maizéoil . I t i s the cheapest oil substitute that has yet been put on the market . I t i s made in twocolors

,brown and straw , and i s used in large quantiti e s in

mechanical goods and in proofing . A good example of thi stype of sub stitute i s that known on the market asDA N KWERTH

’S RUSSI AN SUBSTITUTE—This is said to be a

perfect substitute for both gutta—percha and india rubber, andi s used for covering telegraph cables . H igh temperatures donot aff ect it. I t is made of 1 part by weight of the mixture ofequal parts of wood tar and coal tar O il, with 2 parts ofhemp O il heated until the mass is O f the right consistency. Thenby weight of boi led linseed oi l i s added . To thi s i s

added a little ozocerite and spermaceti . I t i s then heated again ,and finally a little sulphur is added .

DERMATI N E .—A well-known substitute for india rubber and

leather, made O f an artificial gutta-percha called gum percha ,7 pounds ; powdered waste rubber, 7 pounds ; india rubber, 14pounds ; sulphide of antimony, 6 pounds ; peroxide of iron , 2pounds ; flour o f sulphur, 4 pounds 8 ounces ; alum , 4 pounds 8ounces ; asbestos powder, 2 pounds ; sulphuret of zinc , 3 pounds ;


E NDURITE .— The invent i on of John S tuart Campbell

,of

E ngland . The bas i s of i t i s rubber and i t i s used in golf bal ls,

belt ing, etc .EUPHORB IA RUBBER — J. G. B oles reduced Euphorbia gumto a fine powder and

,after dry ing careful ly at a low tempera

ture , put i t in solution and final ly hardened it -’by mixing itwith earthy matters and shel lac .F A Y OLLES

’SUBSTITUTE — A F rench substitute for water

proofing, made as fol lows : 1 part sulphuri c aC1d , 1 part glycerine , 1% part s formal in , 1 part phenol .F ENTON

’S A RTI F I CI A L I NDI A RUBBER— Manufactured from

linseed or s imi lar oi ls , mixed with tar , pitch , or other pyrol igneous products , the mixture being placed in a bath of dilutednitric acid , and allowed to remain until , by the action O f the bathupon the compound , the whole i s coagulated into a tough ,elasti c magna . The black “

F enton” contains as coloring matter a small quantity of plumbago or black carbonate of iron .The gum i s patented by F errar F enton , London , E ngland . I n

his spec ification he modifies i t by taking the art ificial gumdescribed , and placing it in a bath composed of a solution ofsugar of lead , oxide of z inc , saltpeter, or some other form ofnitrate, and , i f high flexibility is desired , adds 5 to 10 per cent . tocopal gum and nitri c acid di luted with water . These solutionsare used one at a time , the proport ion being 5 per cent . O f

sugar of lead , or, for greater hardness, 5 to 7% per cent. of saltpeter to the weight of the magna . B efore vulcaniz ing, thesubstances are washed in an alkal ine solution to remove acid .F enton rubber i s said to have been subj ected to 320 degreesF . for fifteen minute s , the only resul t being to increase i tselastici ty .

F I BRI N E -CHRI STI A GUM i s manufactured just as Christiagum i s, except that silk fibers are used in the place of hemp.

F I G JUI CE P ROOF I NG.—A F rench composition made up offig juice , B razil ian tapioca , and pearl moss, tog ether with vulcan

ized rubber. Used as a preservative and proofing compound .F I RMUS .

-A n English rubber substitute presumably of thesulphurized O il order .

GUTTA -P ERCHA SUB STI TUTES 125

F RANKLI N SUBSTITUTE — A mixture o f coal tar and boracicacid dissolved in alcohol . Boiled and oxidized .

F REN CH GUTTA-PERCHA .—~This gum i s made by boil ing theouter bark O f the birch tree in water. The,result is a fluid,

which is very black, and which becomes compact and solid oncooling. I t has been claimed that it possesses all of the goodpropert ies of gutta-percha , and that in addition it does notoxidize when exposed to the air . I ts appl i cation for industrialpurpose s has been patented .

F ROST RUBBER— A nother name for what is practicallysponge rubber made from any ordinary unvulcanized rubber compound by the addition of a little alum or carbonate O f ammonia.

GRAPE RUBBER—A plaster produced from the skins andseeds o f grapes from which wine has been extracted by pressure .GRI SCOM

’

S SUBSTITUTE— A substitute composed o f equalparts of animal fat,candle tar, and a res idual product from

petroleum, together with sulphur in proportions o f f rom 2 to8 per cent. of the mass .

GRONT A ND MOORE’S REPAI R CEMENT.

'—A mixture of nuvulcanized stamp rubber in benzine solution to which are addedturpentine and collodion .

GUM -CARBO .— Substitute made from cottonseed O il. Used

in general rubber compounding.GUM F I BRI N E i s made of paper rags treated with liquid

carbonic acid,mixed with res in , gum benzoin , and castor oil ,dis solved in methylated alcohol . I t i s an E ngl ish compound .

GUTTA LI N E .- A substitute for india rubber and gutta

percha,manufactured as follows : To Manila gum tempered withbenzine is added 5 per cent . of A uvergne bitumen , also mixed

with benzine . Then add 5 per cent. of resin oil , and allow 48to 86 hours to pass between treatments . The product obtainedi s s imi lar to india rubber. I f i t b e too fluid , the addi tion of 4per cent. O f sulphur dissolved in bisulphide O f carbon will actas a remedy.

GUTTA-PERCHA SUBSTITUTE—F ormula : 2 part s paraffin , 2parts pitch , 2% parts Chinese wood O il, parts chloride o fsulphur, of sulphur. Heat to 100 degrees C . for one hour.


HARMER’S SUBSTITUTE — Composed of 150 pounds wasterubber, 50 pounds P ontianak , 8 pounds A frican flake, 10 poundssubstitute . P atented .

HEVEEN ITE .— A nother name for heveenoid .

HEVEEN O ID.— This i s claimed to be more insoluble , durab le ,

and pliable than almost any other rubber composition . Softheveenoid consists of india rubber 32 parts , camphor 32 parts ,lime 1 part

,and sulphur 8 parts . Hard heveenoid i s made of

india rubber 6 part s , camphor 4 parts , glycerine 1 part , andsulphur 16 parts . H eveenoid i s the invention of Henry Gerner,of New Y ork, and is patented in the United States and Europe .Kauri gum i s also used in certain heveenoid compositions . O ne

special advantage claimed as to the use of camphor is that thechemical compound termed sulphide of camphor i s produced , andtherefore the rubber does not bloom.

HYDROCARBON RUBBER— The invention of Eugene Turpin ,of England . Made by heating a vegetable O il , oxidizing by aircurrent, adding 25 per cent . by weight O f resin , 25 per cent . powdered sulphur, 5 per

.

cent . spirits of turpentine, and 1 to 2 percent. carbon chloride.HYDROLA I N E .

—O ne of the original waterproof fabrics madeby means O f india rubber dissolved in spirits of turpentine andspirits o f wine in equal quantities , and deodorized by O il O f

wormwood .I NDI A RUBBER LEATHER— A compound produced by Nelson

Goodyear in which fibrous substances were mixed with indiarubber to form a body , the surface of which resemb les l eather .

I N SULI TE .—A preparation made o f wood or vegetable fiber,

finely ground and dessicated , and saturated with a mixture consisting of melted asphalt, incorporated with substances of theresin type, with or without substances of the paraffin or anthracene types . The products resulting are used as substitutes forindia rubber, particularly in insulation . P atented by A l fred H .

Huth , London .IRESON

’S P ACKI N G COMPOUND consists O f a mixture of rub

ber, ultramarine blue , and silicate of magnesia .JACKSON ’

S COMPOUND F OR P RI NTERS’ROLLERS .

— S ixteenpounds glue, 16 pounds glycerine , 1 pound borax , 1 pound japan .


W . R . B rixey , changes the original kerite compound somewhat . Cottonseed oi l i s el iminated and talc added . The latercompound is as fol lows

KERI TE .

Coal tarA sphalt

H eat tog ether to 350° F. for hour ; then addLinseed O il

Heat ag a in to 350° F. for 7 hours ; let stand over

night heat up to 240° F ., and add

SulphurHeat up to 320° F. in hour and add

SulphurHeat ag a in to 300

° F. and add

TalcKeep at same temperature V; to 54, hour , whenvulcanization wi l l have.

taken lace, and them ixture can be poured Into mo ds or al lowedto cool in mass .

KI RRA GE COMPOUND— A well-known English patentedcompound , which takes its name from the inventor . I t comesin two forms . The first , to b e used not over 200 degrees F . , i scomposed of india rubber 12 pounds , gutta-percha 4 pounds ,S tockholm tar 25 pounds , chalk 60 pounds , hemp 4 pounds ,and sulphur 10 pounds . The same inventor also recommendsthe following

,to withstand a great heat and pressure : india

rubber 20 pounds , tar 25 pounds , coke , finely powdered , 25pounds ; S tourbridge clay 25 pounds , sulphur 10 pounds , fineemery 25 pounds

,and steel fil ings 5 pounds .

KOMM O ID.—See Corn O il Sub st itute .

LEATHERI NE i s a compound that closely resembles dermatine, and in fact a part of the first patent on that product . It

i s intended as a substitute for leather cloth and i s made as follows : india rubber 28 pounds , substitute 10 pounds , sulphuret ofantimony 13 pounds , peroxide of iron 4 pounds , sulphur 3pounds, sulphuret O f zinc 10 pounds , carbonate of magnesia 23pounds , and sulphate baryta 8 pounds .

LEATH ERUB B ER COMPOUND—Made of ground waste rubber,leather and reclaimed rubber. Manufactured largely in A ustralia .

LEONARD’S SUBSTI TUTE .—Consists of a mixture O f corn oil ,

castor oil , chloride of sulphur, naphtha , and oxide O f magnesia .LI CON ITE

,produced in Holland , i s described as a mixture

of bitumen and various O ils , without india rubber or gutta

LIME I TE—MA P ON I TE 129

percha,elastic and tough , and is claimed to be unaff ected by

water,dilute acids , and alkalies , and neither flows nor cracks in

ordinary temperatures .LI M E ITE .

— A cement that is manufactured from meltedindia rubber, with the addition of 8 per cent . O f tallow, withsufficient slaked lime to give it the consistency O f soft paste . The

addition of 20 per cent. vermilion causes the mass to hardenimmediately.

LI NOXI N .—An insoluble oxy-compound produced by the

Oxidation of certain drying oils boiled in acetone or acetic acid ,f rom which is produced an elas tic mass similar to india rubber.O f F rench origin .

LUFT’S CELLULO ID RUBBER— B y boil ing equal parts ofphenol and 50 per cent . formaldehyde with sulphuric acid and

to the washed and dried product adding india rubber, a compound is formed that , boiled in alkaline solutions , i s transparentand simi lar to cel luloid .

LuGo.—A rubber substitute patented in England , made byheating a mixture of oxidized oi l and rubber to a temperature

at which the rubber dissolves . P otas s ium permanganate i sadded , and the whole heated to 360-400 degrees F . F inelydivided waste rubber i s added , the mas s being stirred and thetemperature maintained . To obtain a harder product sulphurmay be added .

LUGO RUBBER— A n artificial oxidized O il substitute thatonce had a large sale . I t

‘

was black , of about the same specificgravity as india rubber, and made , in connection with rubber,excellent mold work .

MADA N I TE .— A binding material for smooth surfaces , such

as air-pumps , etc., made of 2 parts by weight of vaseline , and 1part india rubber, melted . This mixture may be left for yearswithout perceptible alteration . A low-grade gum used in thesame way in connection with vaseline makes an excellent insulating tape , and has also been used as a friction gum.

MA P ON ITE .—A substitute for india rubber and gutta-percha ,

claimed to be capable o f use in the manufacture of gol f balls ,tobacco pouches , etc . I t i s said to be vulcanizable at 260 degreesF . A n English patent was applied for by F . E . MacMahon.


METALI N ED RUBBER— A name used for compounds used indental work

, under a process patented by C . S . Leadbetter,Man

chester, England , for strengthening the gum with a metallicfabric, woven or knit.

M I NERAL RUBBERS .

So-CALLED mineral rubbers are chemically clas sed ashydrocarbons . Thi s term is a convenient designation for anycompound containing only hydrogen and carbon . Certaingroups of such bodies , both native and artificial , have beenfor years in common use as ingredients in rubber mixtures .

The adaptab i l ity of these b ituminous sub stances to rubber compounding i s due to thei r posses s ing to a greater orles ser degree certain phys ical resemblances to india rubber

,

especial ly plasticity and a low melting point . These characteristics permit the bitumens to be combined easily with rub

ber and earthy matters and in thi s way very cons iderab lyas s i s t the mixing of otherwi se overcompounded or utterlyunmixab le stocks . Such hydrocarbons being practically proofagainst Oxidation and inert to chemical action

,are entirely

harmles s as aff ecting the durabi li ty of the stock . They maybe credited with actually having a beneficial effect

,inasmuch

as they not only add plasti city to the s tock and retard its rapiddrying before vulcanizati on , but they fi l l the space otherwiseoccupied by , and exclude much of , the ai r which i s alwaysincluded to a cons iderab le extent in every rubber mixing . B ythus excluding ai r the hydrocarbons practically les sen internal oxidation and In consequence the durability of the goodsi s increased . I t has been demonstrated experimental ly thatcertain of the sol id mineral rubbers” actually increase thetens i le s trength in mix ing s under favorable condit ions .

There i s a recognized place and value for both liquid andsolid hydrocarbons in the manufacture of rubber stocks , but theyought always to be considered as “assistants” rather than as substitutes for

‘

rubber , which they are not .Among the bituminous substances usually referred to as

mineral rubbe rs are the following hydrocarbons , the specificgravities of which are about

E LATERI TE .—A natural mineral bituminous hydrocarbon .


7 pounds . I t is said to be easily mixed with ordinary rubber,vulcanized in the usual way, the price b eing about the same asfor reclaimed rubber.

O H M LA C.— A hydrocarbon put up in diff erent consistenciesto suit va rying compounding needs .

O KON ITE .-A well-known compound for insulating wiresand cables . A ccording to an English analyst, it consists o f india

rubber per cent. ; sulphur per cent . ; lampblack percent . zinc Oxide per cent . ; l itharge per cent. ; and sil icaper cent .O X OLI N .

—A n English invention patented by Charles J . Grist ,an electrical eng ineer, and identical with perchoid” in the

United S tates . Thi s gum i s used for waterproof sheeting,printers’ blankets , packings , etc . I t is made o f a solution ofpartially oxidized O il by adding litharge and heating to over 400degrees F . Jute, or other fibers , i s then dipped in the oil, thesurplus oil is removed in a hydro-extractor, and the oil remaining on the fibers is oxidized by a current o f air. These Operations are repeated twice . The material i s then ground with sulphur and coloring matters , and treated like india rubber.

P A RAGOL.- A high-grade corn O il substi tute .

P A RKES I N E .— Made from a compound of linseed oil and

pyroxyline , and used in the manufacture of small a rticles thatare sometimes made of hard rubber. A parkes ine compound formolding

,proofing, etc ., i s as follows : To 500 pounds water add

50 pounds sulphuric acid , and steep it in as much cotton , or rags ,or jute , or linen as the liquor will moisten , for 3 or 4 hours .Take out, drain , and expose the mass to steam heat o f about 280degrees F for an hour, i f cotton or jute fiber has been used , and3 hours i f flax . Neutralize the acid pulp with a bath of waterand soda , using 4 pounds O f carbonate o f soda to every 200pounds of rags . Wash and press , pass through a coarse sieveof 12 meshes per inch , and dry . Grind the g ranulated materialand si ft it through a sieve of 120 meshes to the inch . The resulting powder may be mixed , in all proportions up to equal parts ,with fresh rubber. Compounding 25 to 50 parts d ry parkesine,with 50 parts alcoholic solvent. A proofing compound is : 1pound paraffin , l inseed oil , or other drying oil ; 4 to 8 ouncesparkesine.

P EDRYO ID— P URCELLI TE 133

P EDRY O ID.—A rubber- l ike finish for cloth , made presumably

O f O il, in tan , brown , olive , and other colors , and used chiefly inshoe finishing.

P EN SA’S RUBBER—A F rench substitute made as follows100 parts O f boiling coal tar, petroleum tar, O il of turpentine, ormineral oils , and 25 parts of boric , or phosphoric acid dissolvedin alcohol , and the vapors are ignited , and the flame extingui shedas soon as a green color i s seen . The mixture is then heated at60 degrees C. in the presence of oxygen , until a viscous ductilesubstance is Obtained .

P ERCHO ID.— See O xolin.

P EROXIDE SUBSTITUTES— P eroxide O f lead having been recommended as a better drier than other oxides used in connectionwith all compounds , the following formulas are given : 25 partso f walnut oil , 62 parts linseed O il, parts peroxide O f lead ,parts sulphur . O ne of greater toughness i s composed of

25 parts walnut oil,56 parts l inseed oil , 5 parts peroxide O f lead ,

6 parts sulphur, 6 parts gum juniper.P I CKEUM SUBSTITUTE — This is made by the following treat

ment O f P ickeum gum

Boi led l inseed O il 160 pound s.

Vaseline 20 pounds .

Bastard gum (or P ickeum gum) from CentralAmer ica, cut fine 40 pounds.

Stir and heat to 250 degrees to 300 degrees F ., until thegum i s di ssolved . Then cool to 100 degrees F .,

and strain .B

Solution as above 5 g al lons.M ixture of P rotoch lor ide of sulphur 9 pounds .

B isulph ide of carbon 9 pounds .

A fter the chemical action takes place,the mass i s graun

lated and the grains are washed and stored for use, or the material may be masticated in a rubber mill and run into sheets foruse.

P URCELLI TE .—The invention of Dr . C. P urcell Taylor, of

England . A n insulating substance somewhat similar to guttapercha , but costing much less . I t i s said to be very tough andelastic, may be made of any color, and is either flexible or rigid .


The specific gravity of the material is I t can be molded orvulcanized like india rubber. I ts insulation resistance is equalto that O f gutta-percha . I t is unaff ected by atmosphere, by alkaline or acid l iquids , freezing mixtures and the l ike .QUI N N ’

S RUBBER—An English substitute made from petroleum, bisulphide of carbon, chloride o f sulphur, and rapeseed O il .

RA TH ITE .— A mixture in which waste silk fibers are incor

porated w ith india rubber to impart resiliency and durability.A bout 6 ounces o f silk are used with 28 pounds of rubber compound . I t i s employed in making ti res , pump valves , packings ,etc. P atented by A . I . Rath , Cheshire, England .

RESI N OLI N Es .— Substances so called by Eugene Cadoret , o f

P aris , who obtains them by saponi fying various O ils by the useof a metallic carbonate , using by pre ference carbonate of lead ,then decomposing by nitric acid

,decanting, and saturating with

an alkali . The soap thus formed is treated with acid to form aresinoid body, purified by dissolving in alcohol , and evaporatingthe solution . Res inolines thus formed are very similar to natural resins . They are either semi-fluid , pasty, or solid . Whensolid , they are remarkable for their flexibility.

RHEA GUM — Rhea fiber washed and dried ; immersed in asolution O f silicate o f soda ; then carefully dried ; then immersedin a bath O f resin or other heavy hydrocarbon oil at a temperature O f about 275 degrees F . ; then put in a hydro- extractorwhich is, worked at a temperature of 300 degrees F . , when thesuperfluous O il i s extracted ; the mass is then dried . Later it ismixed with gums , resins , india rubber, or gutta-percha , and rheagum i s the result .

R I CE RUBBER .—Japanese or M achi rice treated so that it

makes an elasti c cellulose product .RO SALI N E .

—A vegetab le product said to contain about thesame chemical elements as india rubber , and of about thesame specific gravity . M anufactured in the United S tates ,F rance

,and E ngland . A strong point i s made by the manu

facturers that after vulcanization no chemist i s ab le to detectthat there i s anything but pure rubber in a mixture containing 25 pe r cent . of rosaline and 75 per cent . of india rubber.


Othe reason that it has been found useful in vul canite com-3

pounds , whi l e at the same tlme It may be used in ordinarysoft rubber work .

RUB -H IDE—Thi s i s a patented compos ition made fromraw hide . I t i s very rubbery in consi stency.

RUSS IAN SUBSTITUTE—M anufactured from the skins ofrabb its and other smal l animal s

,or the waste therefrom

,

digested in crude glycerine , and a little water . The formula i s3 parts by weight of the cleansed substance melted in water

,

with 3 parts by weight O f crude glycerine , to which i s addedpart by weight of a concentrated solut ion of potass iumchromate . The resul tant mass i s flexible . To make it harder,a littl e les s glycerine and more chromate of potash are tequired . To withstand acids , 30 per cent . of gum lac di s solvedi n alcohol i s added . F or waterproofing fabrics , part byweight of oxgall i s added , with enough salt water to give itthe consi stency of oi l .

SA Rco.—A rubber assistant, probably made from treated

elaterite .SOAP SUBSTITUTE S —These have been exploited and ex

plained more thoroughly by P rofessor W . Lascel les-Scottthan by anybody else . The typical formulas that he gives areas fol lows : 28 parts of aluminum soap , 60 parts of linseed oil ,8 parts of acid free sulphur , 4 parts of oi l of turpentine . A n

other,to us e in connection with reclaimed rubber, i s 15 part s

of aluminum soap , 25 parts of d evulcanized rubber , 60 part sf resh rubber, benzine quantum sufi

’icit. A nother still , in whicha low grade pseudo-gutta i s used , i s 15 parts aluminum soap ,25 parts A lmeidina gum,

5 parts raw rubber,6 parts sulphur,

and 4 parts oleum succini .SOLI CUM .

—A sub sti tute or rather a compound patentedby a chemist in Copenhagen . The basi s of the di scovery i swaste rubber and oi l .

SULO .-A sulphur oi l sub stitute manufactured in the

United S tates .TA B B Y ITE .

—A mineral product from Utah which seems tobe a mixture of asphalt and paraffin oils . It i s easily manipulated and qui te elast ic .

TEX TI LO ID— TREMENCL 137

TEX TI LO ID.-A mixture of a res inoline (as described byCadoret under that heading) with natural resins , cel lulose ,nitro-cel lulos e , or organic sub stances of animal origin . The

resultant material may b e transparent , white, or colored . I t

i s -practically uninflammable, has no smell, is very elastic, and ,if submitted to heat,softens , and can be easi ly drawn out

into fine threads . I t can be us ed for waterproofing and invarious other ways i s a good sub sti tute for india rubber. I t

i s flexible and elastic . Textiloid i s made of 4 parts res inol ine ,2 parts nitro-cel lulose , and 1 part camphor diss olved in alcohol at 90 degrees F . The result thus formed may b e made incolors by the addition of metall ic oxides .

TH ESKELON CEMENT.—A metallic substance used for water

proofing and for certain kinds of packings . I t will neither expand , contract, nor rust. I t i s used instead of wax for sealingpurposes , and resists acids , alkalies , and grease. It is often usedin place o f asphaltum . It can be mixed with tar, pitch , asphaltum, and other similar ingredients , the compound possessing extraord inary adhes ive power . P atented by Thomas Smith , London .

TONG O I L SUBSTI TUTES .- Manufactured from the Chinese

oil known as tong oil,or wood oil . The oil i s heated without

any foreign matter being added to it, at a temperature of 250degrees C., when it becomes solidified . I t i s then pulverized ,and impregnated with petroleum , which swell s it , and rendersi t more easily worked . P atented by Dr . Charpes Repin , P aris .

TREM EN OL.— A Ge rman invention that has reference to the

production of sulphonic acids, sulphones , oils , resin oils , mineral waxes , etc . Results f rom a treatment of mineral matterwith fuming sulphuric acids at ordinary temperatures , or withconcentrated sulphuric acid at 120 degrees C. The inventionfurther call s for the treating similarly of the bodies obtainedfrom the oil in their precipitation by means of sulphuric acid .The products are then washed in brine and water. The inventorsprecipitate glue and gelatine f rom a slightly acid solution , aselastic rubber- l ike substances that can be drawn into threads withperfect ease .

TURN BULL’S A NTI -F OULI NG RUBBER P AI NT.— P itch and resin

are melted together, and then a mixture consisting of crude

138 SUB STI TUTES F OR RUB B ERO

naphtha , dis solved P ara rubber, and s ifted whiting is addedthereto .

TURPENTI N E RUBBER.— Manufactured by passing spirits of

turpentine through a heated tube so as to vaporize it, and mixing the vapor with hydrochloric or other acid , so as to condense and solidi fy all o f the vapor. P atented by A . F . St. George ,England .

UNVULCAN I ZED P ACKI NG WASH ERs .—Goldstein claims in an

English patent a washer material for the sheet-metal lids of vessels is made , without containing sulphur, of a mixtureof cruderubber, talc, asbestos, and gutta-percha .

VELVR I L .— B asi s , a drying or semi-drying oil ; treated with

strong nitric acid . Thi s i s compounded with nitrocel lulose .B y varying the proportions any cons istency may be obtainedfrom that of vulcanite to a soft , elasti c , rubber- l ike substance .The product i s nearly colorl es s in thin layers , which shows anelas tici ty of about 25 per cent . , but no greater res i l ience . I nvented by W . F . Reid , of E ngland .

VOLEN ITE .—A sub stitute for india rubber and gutta

percha invented by F rederick Lamplough,United States . The

compound i s said to b e a mixture of resins , or res in oi l convey ed into a mass of fibrous material by a sui tab le non-oxid izable oil . This latter oil i s used simply as a vehicle to carrythe res in to it s place

,the proces s b eing completed by the dis

tillation of the non-oxidizabl e oil , and the oxidiz ing of therest of the mass . The oil used i s preferably a fish oil , whichi s refined careful ly before use . A fter saturation and treatment the vegetab le fiber i s changed into a homogeneous masswhich has many of the characteri st ics of vul canite . A formulathat is said to have workedwel l i s 10 parts by weight of fiber,5 parts res in oi l , and 2 parts fish oi l , treated at a temperatureof 130 degrees C.

,for say 4% hours .

VOLTAx .— A n A merican insulating compound not subj ect

to chemical change,and proof aga i nst water, acids , and alka

l ies . I s cheaper than rubber and does not affect copperhence tinning of the wires i s not necessary .

VOLTI T.— The base of thi s i s glue or gelatin prepared from

scraps of kid skins,which are treated unti l they reach a gela


mable , and not injured by salt water. I t i s used in makingvalves , packings , etc . I t i s c laimed that it wi ll not b ecomesticky or soft under heat or steam pressure , and wil l standhot grease and other lubricants

,and neither acids , alkal ies ,

nor wastes from oi l refineries , disti l l eries , etc ., aff ect i t i nthe l east . A compound for wood ite or whaleite packing i s :asbes tos fiber 38 pounds , asb estos powder 38 pounds , earthwax 6 pounds , charcoal finely ground 9 pounds , ground whalebone 20 pounds , P ara rubber 80 pounds , and sulphur 5 pounds .

ZA CK I NGUM M I .- Substitute i nvented by Zachias O ls son , a

Swedish chemi st . Consi st s of a mixture of glycerine , chlorideof calcium ,

magnes ium , and paraffin .Z I N SSER’S B ARREL L1N 1N G.

—A compound for l ining casks ,cons ist ing of deodorized copal

,rosin , i ndia rubb er, and a non

drying fat , with coloring matter, such as asphalt .

CHA P TER Vl ll .

SUB STITUTE S F OR HA RD RUB B ER A ND GUTTA

P ERCHA INCLUDING CELLULO SEP RODUCTS .

HARD RUBBER in it s b es t estate i s so valuab le and perfecta product that i t would always have the preference were itnot for it s unavoidabl e high cost . B ecaus e of thi s cost thereare many substi tute s for i t that counterfei t i t in texture

,color

,

and quali ty , but are never quite it s equal in al l these pointsof excel lence . These substitutes are made of cellulose , gums ,and animal , vegetable , and earthy matters , having a variety ofdi stinctive names and varied uses . To the popular mind , i fthey look like ebonite , they are hard rubber. I n the same way,gutta-percha i s often confounded with hard rubber, which itresemb les under many condit ions . The fol lowing li s t coversnot only certain widely known compounds of hard rubber andgutta-percha , but a number of substitutes for them are nowput to many us es , the chief of which , perhaps , i s insulation .

A LEX ITE .—A n American insulating material which can be

molded in any shape,i s waterproof, fireproof, and acid proof,

and can be produced in any color. I n texture and generalappearance i t resembles vulcanite .

A M B RO I N .—A German sub stitute for hard rubber, consi st

ing of fiber, s il ica , and res in compressed to a mass . I ts colorvari es from light brown to green or black . N i tric and aceticacids do not aff ect i t , and even aqua regia does not injure it .Under a moderate heat i t softens s l ightly and can be worked ,l ike vulcanite , in a mold . I t also takes a bright finish fromthe buffing wheel .

A RM A LA c .— See I nsulae .

A RTI F I CIAL W HALEBON E .—A well-known product made as

follows : india rubber 20 parts , sulphur 5 parts , shellac 4 parts ,magnesia 4 parts , and gold brimstone 5 parts . Vulcanizedsomewhat the same as hard rubber.

141

142 SUB STI TUTES F OR HA RD RUB B ER

B AKELITE .—A patented substance said to have the com

bined properties of amber, cel luloid , and hard rubber. The

invention of Dr . L. E . B aekeland . I t i s a compound of orcondensation product of formaldehyde and phenol or carboli cacid . I t has long been known to chemis ts that formaldehydeand phenol formed condensation product s which have beenput on the market as artificial gums and resins and used tosome extent . I t was further known that by a certain proces sthis material was condensed into a hard , resmous body whichres isted every known chemical solvent and was only cflang edby actual burning. Thi s sub stance was usual ly porous andwas of no value . Dr . B aekeland di scovered that , by carrying on the proces s in a vulcanizer where heat and temperature conditions could b e controll ed , the reaction could b edivided into several stages , producing firs t a plas tic mas swhich can be molded or carved , and on further treatment inthe vulcanizer where i t i s submitted with certain chemical s tocareful ly regulated conditions of heat and pressure

,that a

hard,transparent sub stance could be produced which i s most

inert chemically. B akelite resembles physically and possiblychemically the Chinese or Japanese lacquer, I t i s manufac

tured into a large variety of electrical goods such as terminal s ,high potential insulators and

,in i ts l iqui d form , i s used to

impregnate armature and other coi ls , the impregnated material b eing sub sequently converted by heat into the hard form .

B akel ite takes a high poli sh and machines freely . I t i swel l adapted to manufacture in rubber works , as most of themachinery can be used with l itt le change .

B A LEN ITE ,as the name signifies , i s intended as a sub sti

tute for whalebone . I t i s qui te elastic ; in other words ,i t i s neither hard nor soft , but may be characterized assemi-hard . A well-known compound for this i s india rubber100 parts , shel lac 20 parts , burned magnesia 20 parts , sulphur25 part s , and orpiment 20 parts . (Hoff er.)

B ETITE .-A n E ngli sh insulat ing material which i s said to

be bitumen refined to absolute purity and vulcanized ..

I t i sused on cables , in underground work , for low pres sure res istance

,and in rare instances for high pressure .


of cotton or filter paper which has been treated with acids todissolve out impurities , and forms a basis for the manufactureof celluloid , gun cotton , py roxoline, and xylonite . O n analysisit shows : carbon hydrogen oxygen I t i s dissolved in sulphuric acid , and is converted into dextrine, and ,by prolonging the action

,into glucose . So far it has not been

used largely in rubber compounding, but both alOne and in connection with various other ingredients has been appl ied as awaterproofing . I t i s the bas i s of certain Swiss puncturefluids .

CE -RE-GUM .—A compound made by a secret process , and

which,vulcanized, produces a fairly good imitation of hard

rubber. I nvention of H . W. Morgan , United S tates .CHATTERTON ’

S COMPOUND.—A widely known compound

sold the world over for connections for j oint sheets and foruniting gutta-percha parts , and also for cementing gutta-perchato wood . It softens readily at 100 degrees F ., and becomes firmagain when cold . I ts specific gravity is about The bestcompound is 1 part by weight O f Stockholm tar, 1 part resin ,and 3 parts Cleansed gutta-percha , melted and mixed .

CONDEN S ITE i s a phenolic condensation product invented byJ . W. A ylsworth , who for more than a quarter of a centurywas as sociated with Thomas A . Edison , as his chief consultingchemist.

Condensite was developed in the course o f a search for abetter material to be used in the manufacture of phonographrecords . I t i s the only phenolic condensation product that hasever been success fully used in the making of a record

,which . i s

probably the most difficul t plastic molded article to manufac

ture without imperfections .Condensite i s unlike any other phenolic condensation prod

uct, because of the unique method by which it is made . B ythis process the product , during the reaction between the chemicals of which it is composed , i s heated to such a degree as todis sociate al l the water.

The absence o f water, even in minute quantities , gives tothe final product a capacity for taking extremely minute impress ions in molding

,as wel l as impart ing to them unusual

electrical and other qualities of value .

CONDENS I TE— ELE CTROSE 145

The next step in the manufacture of condensite very muchresembles that of rubber manufacture . I t i s compounded witha chemical that r eacts upon it when heated , and hardens theproduct , just as sulphur O r other vulcanizing mediums hardenrubber when similarly treated , and the process of molding isvery much the same as in rubber manufacture .

Condensite has in some instances been used in the place o frubber, but its development has chiefly been in competition withother substances, and with respect to rubber rather supplementsthan serves as a substitute for it. Each possesses valuable properties not found in the other.

CORA LI TE .—A name for vulcanite which is colored to imitate

coral .CORI M ITE i s a sol id substance derived from fish ofi‘al through

a process recently invented by a Danish chemist , and said to beparticularly suitable for electric insulation .

CORN ITE .-A specially hard vulcanite or hard rubber, sonamed from the Latin comu (a horn ) .

DE P ONT SUBSTITUTES .—A n English patented product madefrom asbestos 30 parts, plaster of P ari s 5 parts , clay 8 parts ,copal 15 parts , tar 5 parts , bitumen 15 parts , aniline 2 parts ,

lampblack 15 parts , mica 4 parts , wax 3 parts .DI ATITE .

— A combination of diatomaceous earth , and shellac ,made under very heavy pres sure . I t may be made O f any color,and is used as a substitute for hard rubber.

E B ON ITI N E .— A hard rubber substi tute formerly us ed for

phonograph records . I s of a bri l l iant black color. Said to bea good insulator and res ists acid . O f German origin .

ELECTROSE .—A substitute for hard rubber for which the fol

lowing advantages are claimed : It will not tarnish metal , asno sulphur is used in its vulcanization ; it is cheaper than hardrubber ; it possesses high insulation properties ; it can be meltedreadily into ’

any Shape, or made of any color ; it does not fade ;it possesses great strength , and takes a high polish ; changes oftemperature do not aff ect it ; and it withstands the weaker acidsand alkalies .

E SB EN ITE .—M ade of pure cel lulose , chemical ly incorporated with mica in the form of fine powder, w i th the addi tion

SUB STI TUTES F OR HARD RUB B ER

of magnes ia and a s ili cate , thus forming strong and closegrained artificial mica . I t i s flexib le , and can be molded intoany Shape . E sbenite i s waterproof

,does not burn readi ly

,and

i s thoroughly airproof . M anufactured in England .F I B RON E .

—A sub stitute for hard rubber which i s a goodnon- conductor , waterproof, and can be handled in a lathe l ikevulcanite . I t i s said to b e durab le

,does not contract or ex

pand , and i s made in al l colors . I t i s used for thumbscrews ,pushbuttons , etc . P lasticon i s S im i lar to fib rone, but heavierand of a more stony nature , and probably made of the samematerial .

GALALITH .—A German product from casein . The proces s

roughly i s to make the casein insoluble by the addition ofsalt s and acids . The product i s then dehydrated and dried ,when , by the addition of formaldehyde , galalith is obtained .The proces s i s protected by numerous patents .

GUN COTTO N — P repared by treating cotton wool with amixture of strong sulphuri c and nitric acids , or nitrate ofpotash may be substi tuted for nitric acid . A fter treatmentwi th acid the gun cotton i s rinsed careful ly in cold runningwater

,and then dried by pres sure or by exposure to the air.

A ll acid Should be removed to prevent danger of explosion .Gun cotton has b een used to render fabrics waterproof, forvarni shing india rubb er to render it imperv ious to gases , andi n insulation work . A l exander P arkes , as far b ack as 1855,used a solution of gun cotton with gums or resins to take theplace of compounds of india rubber . H e rendered gun cotton les s inflammable by us ing biphosphate of ammonia , magnes ia,talc

,alum

,or sim i lar sub stances . A s a good solvent

for gun cotton , he di sti l led in 1 gallon of naphtha from 2 to6 pounds of chloride O f calcium . Charl es M acintosh us ed asa solvent equal parts of wood spirit and coal tar naphtha .HARD CORE F OR GOLF B ALLS .

— A n E ngli sh compositionwhi ch consi sts of 100 part s calcium ch loride , 25 parts chlorideof z inc

,100 parts potato starch .

HYALI N E .—M ade of a mixture of equal part s of gun cotton and a var i ety of resins . The gun cotton i s di s solved inether and the resin s in solution are added , the resul t b eing a

148 SUB STI TUTES F OR HARD RUB B ER

stain s to be washed off . A n artificial leather i s also made ofKeratol . The name is adapted from the Greek word keros

,mean

ing hornlike .K I EL COMPOUNDS'

.—O ne of these wel l-known composi

t ions consi s ts of india rubber,sulphur, pumice stone , O il, and

beeswax . The product i s a hard rubber , said to pos ses s asuperior elasticity and toughness

,and capabl e of b eing vul

canized in Sheets at least 2% i nches thick . This compoundis not aff ected by the most intens e cold, and wi ll stand ahigher temperature than ordinary rubber. I t also burns withdiffi culty . I ts i ngredients are said to mix faster and moreuniformly than those of other compounds . I t res ist s acids ,and other corros ive substances , i s a perfect insulating material , and is cheap . A nother Kie l compound i s made of indiarubber, sulphur, and mineral oi l . I t i s more flexible thanordinary hard rubber, and when warm i s more plastic thansuch compounds . I t i s al so les s b ri ttl e and cheaper, and canb e turned in a lathe with greater facil i ty and les s injury tothe tools .

KORN ITE .— A Russian substitute for hard rubber made at

Riga . It consists o f 25 per cent . of prepared fish bone and 75per cent. of scrap horn ground to dust, and then melted underhigh pressure and steam heat .

LA CTITI s .— A n artificial ivory made from milk, the process

be ing coagulation, straining, and rej ection of the whey. Ten

pounds of the curd are then taken and mixed with the solutionof 3 pounds O f borax in 3 quarts of water. The mixture is thenplaced in a vessel over S low fire and left unti l it s eparates intotwo parts , one as thin as water, the other resembling meltedgelatine . The watery part i s drawn off , and to the residue isadded a solution of 1 pound of mineral salt in 3 pints o f water.(Sugar of lead answers very well as the mineral salt . ) Thisbrings about another separation of the mass , into a liquid anda mushy solid . The liquid is strained or filtered Off , and at thispoint coloring matter may be added . The solid is now subj ectedto heavy pressure in molds of any shape , and afterwards driedunder great heat. The resulting product may b e used in themanufacture of billiard balls , knife handles , or anything forwhich ebonite or celluloid i s adapted .

LEA THERO ID— P EGAM O ID 149

LAM I NA F I BER—An American invention, used chiefly for

electrical purposes . I t i s o f various colors , heavier than vulcanized rubber, and swells to nearly double its weight whenplaced in water. It i s probably a cellulose compound containingno rubber.

LEATHERO ID.—A mixture of American origin , made in black,

red and gray, and similar to vulcanized fiber. I t i s insolublein ordinary solvents, uninjured by alcohol, ether, ammonia , turpentine, naphtha, or other oils ; i s very tough , a good insulator,and of low cost.

MARLO ID.— An insulating material said to be made from the

hides of certain animals,treated by a chemical process , making

it so hard that it can be handled in every way the same as ebonite . I t may be transparent or Opaque, and is capable of receiving a very high polish . I t is said to give an insul ation ofmegohms , i s uninflammable, and o f English origin .

M I CAN I TE .— M ica cemented together under pressure with an

india rubber compound . Manufactured in America .N I GRI TE .

—An insulating compound consisting of a mixtureof india rubber and ozocerite.

N ITROCELLULOSE .— This is produced by the action

'

upon cellulose of nitric acid or a mixture o f nitric and sulphuric acids .A ccording to the length of time the acid is allowed to act, theresult ing nitrocel lulos e contains or 28 per cent .of nitric acid (nit ric-anhydride ) . Gun cotton is usually a mixture containing higher percentages, while pyroxylin— or, as iti s sometimes called , soluble cotton— i s a mixture o f lower compounds . The solution of pyroxylin in a mixture O f alcohol andether i s called collodion .

P A NTA SOTE .— A cellulose product largely used in the manufacture of artificial leathers .

P EGAMO ID.—This

,although covered by several patents , i s

said also to involve certain secret processes . In a general way,however

,the substance is prepared by treating a fine grade O f

cellulose with a mixture of sulphuric or nitric acid to form nitrocellulose or gun cotton , which is then dissolved in a suitable


alcohol . The pegamoid patents call for the addition of glycerine ,sweet or O l ive oil , and various coloring matters .P LA STI CON .

— See F ibrone.

P LA STITE .- A vulcanite which is made extra hard and is

not possessed of.

any special amount of elasticity. The stockrecipe for this is : india rubber 100 parts , sulphur 25 parts , magmesia 50 parts , orpiment 50 parts , coal tar asphaltum 60 parts .I t i s very hard and sol id , and takes a high degree of smoothness and polish . (HOfl

’er)

P OTATO CELLULO ID—A n A ustri an I nvention relating to ' anart ificial sol id produced from potatoes boi l ed 36 hours in afluid containing 8 part s of sulphuri c acid and 100 part s ofwater, and then dried . P ipe bowls made from it for the F renchmarket are said to be hardly distingui shab l e from real meerschaum . B i l l iard ball s. are also said to b e made from it .

P RESSP A H M .—A n Engli sh insulat ing material made from

wood fiber s o treated that i t can be run through rol l s intosheets of varying thicknes ses . I t i s said to be capabl e of withstanding high temperatures , and i s used not only in connection with electriEal machinery , but also for bookbinding andfor putt ing a finish on c l oth .

P YROX YLI N .— A species o f gun cotton less explosive in itsqualiti e s , prepared from cellulose by means of nitro- sulphuric

acid . I ts solution in a mixture of ether and alcohol i s cal ledcollodion .

S I LUM I N ITE .—This new insulating material , of E nglish

origin,i s a hard b lack sub stance , ringing l ike slate , but of far

greater strength ; i t can be sawed , fi l ed,dri l led , tapped , turned ,

and poli shed with eas e,and can be molded to any Shape in the

course of manufacture , but not afterwards . I t i s not softenedby heat (it i s subj ect to a temperature of more than 600 degrees F . at the makers’ works ) and i s not brittl e . Immersionin oi l or caustic alkal i , or boil ing water, l eaves i t unchanged ,and it i s non-hygroscopic . I t possesses high dielectrics trength

,this being between and volts per mil l i

meter. I ts s tructure i s homogeneous and dense , the weightof a square foot - inch th ick , being pounds . M etal partscan be insulated by compress ing '

S iluminite on them in any

152 SUB STI TUTES F OR HARD RUB B ER

VULCA B ESTON .— A composition o f asbestos and india rubber,

forming a product which is a non-conductor of electricity andstands the severest tests , resisting heat wonderfully. I nventedby R . N . P ratt, United States .

VULCAN I ZED F I BER— This material,which is very largely

used , i s made of cotton paper pulp , chemically dissolved , andsolidified under enormous pressure . I t i s unattacked by ordinary solvents such as alcohol

,turpentine, ammonia , etc . I t

appears on the market in two i

forms— hard and flexible . The

hard fiber resembles horn and is exceedingly tough and strong,while the flexible fiber has the appearance of a very close-grainedleather. I t i s an insulator in dry places , but, as it w il l absorbmoisture, it i s useless in places requi ring waterproof qualities .I t i s made in three colors— black, red, and gray. Vulcanizedfiber is unaff ected by oils or fats , and will stand action of hotg rease . Low grades have been found adulterated with chlorideO f zinc and calcium , to the extent o f nearly 50 per cent . o f itsweight.WEBER’S CELLULOSE COMPOUND—Ten pounds of cellulose

steeped in a 20 per cent . solution o f caustic soda and allowedto stand for ten hours ; then pressed until its weight is 35 pounds ;then treated with 8 pounds cold carbon b i- sulphide for threehours ; then emulsified with a mixture o f 40 pounds P ontianakgum, 15 pounds mineral oil , and 10 pounds stearine pitch .WI LLOUGHBY SM I TH’S GUTTA-B ERCHA . -Gutta-percha re

fined by a special process invented by Willoughby Smith . Valuedin England as giving an increased Speed over electrical conductors insulated with it.WRAY’S COM P OUNDr

-

j—A composition of india rubber, silica ,

powdered alum, and gutta-percha . Used in climates too hot forgutta—percha by itsel f . It i s easily attacked by seawater.KELTON .

— A substitute for hard rubber manufactured principally for use in making battery jars . I t originated in P hiladelphia .

X YLON I TE .— See Celluloid .

CHA P TER IX .

RES INS ,BA LSAMS , GUMS , EARTH WA X ES , A ND

GUM -LIKE SUB STA NCES USED I N

RUB B ER COM P OUNDING.

A GREAT variety of vegetable, mineral , and 'animal res insand waxes find uses i n admixture with india rubber and guttapercha . Their important uses are to render compounds adhes ive, as in frict ions , to ass i s t in in sulat ion , to 'add luster,and to modify the texture of the vulcanized compound . M anygums

,l ike many -earths

,l end special virtues which they pos

sess to rubber compounds . The more important of thes ematerials

,and those most general ly used

,are described in the

fol lowing pages .A CACI A. —See A rabic, gum.

A CRO IDE S GUM,also known as B otany Bay gum or minerallac, i s the name given to the resins O f the various branches of

the X anthorrhaea plant species .Red gum acroides comes from the X anthorrhaea A u

'

s trah'

s andA rborea. I t forms flat pieces from one-hal f to one and one-hal finches thick, sometimes as big as the hand , shows distinct t racesof its structure and embraces unresinified tissues . I t i s reddishbrown in color , l eaves an orange- red mark , smel ls somewhatlike benzoin , and has an unpleasant taste like cinnamon .

Y ellow gum acroides comes from the X anthorrhamHas tihls‘,

forms round or oval pieces of various sizes , resembles gambogeon a fresh fracture , becomes covered with reddish brown coating on exposure to the air, smells like benzoin, has a somewhatsweet or Spicy taste

,and contains in addition regular admixtures .

Both gums are soluble in acids and ether. They containparacoumaric acid, benzoic acid , para- oxy-benzin-aldehyde andabietic acid, the yellow gum having also traces of cinnamic acidand styracin . They are used in the manufacture o f sealing waxand colored varnishes which do not fade on exposure to the

153

154 GUMS AND B ALSAMS

l ight and which are suitable for painting the glasses of photo~graphic dark- room lamps . They are also.employed in making

the better classes of Soap ; in the preparation of picric acid andparacoumaric acid, as well as in the linenizing of the thinnerqualities of paper. F or insulating purposes aeroides is meltedand mixed with other ingredients and molded to form insulating pieces for electrical apparatus . The exact process is a manufacturing secret.

A croides was used in England in the eighteenth century as amedicine for the stomach , but it was not employed for manufacturing purposes until 1840 in England and 1860 on the Continent.

ADA M A NTA RE S I N .-A n imitation copal , manufactured

from common res in by a special hardening proces s . I t i s notsolub le in alcohol or benzine , but completely so in boi l ingturpentine . I t i s free from acids and alkal ies , and has the samemelting point as Zanzibar copal . I t i s us ed rarely in rubberShoe 'varni sh , and often in cheap fri ct ions in mechanical l ines ,being moistened w ith resin oil to increase its adhesiveness .

A MBER—A foss i l res in chiefly found in P russ ia , on theshores of the B altic s ea ; i t occurs al so in S ici ly and sometimes in the United S tates . I t i s the hardest and heaviest ofthe resins . I ts specific gravity i s about B y disti l lationa yellow oil— oleum succini or oi l of amber— i s obtained , anda yel low res in remains in the sti l l . Amber varies in colorfrom light yel low to a deep brownish-red . I t i s insolub le inalmost al l of the ordinary solvents . When heated above itsmelting point , however, i t becomes partly decomposed , andi s then soluble in oi l of turpentine and alcohol . I t makes avery fine transparent varnish , which i s us ed on negatives inphotographing. I t i s used in cements for fastening l inoleumand rubber ti l ing to decks , and i s als o mentioned in the formulas for certain patented gums .

A MMON IACUM GUM .—Exclusively obtained from P ers ia as

tears , or aggregated masses , of a pecul iar smel l and a tasteS l i ghtly sweeti sh

,bi tter

,and somewhat acrid . I ts specific

gravity i s Us ed in solutions for pres sed leather cutt ings and fibrous wastes . Ten parts of thi s gum mixed with

156 GUMS AND B A LSAMS

i n certain ‘

Sub stituteS l ike kerite . Commercially there are twogrades

,known as “ lake pitch” and “ land pitch ,” of which the

latter i s the harder .I n solution it i s us ed sometimes to protect rubber goods

that are exposed to the destructive influence of brine . A l itt l easphalt i s also said to increas e the elasticity of hard rubber .A sphalt mixed with res in and oil of tar forms a low-gradeartificial gutta-percha . I t i s added to “Cooley’s artificiall eather” to harden it and enable i t to res ist heat . I t i s al sothe bas i s of one type of marine glue .” M l

A SPHALT, A RTI F I CI AL.— This is made by heating sulphur andresin together to about 250 degrees C., where the reaction takesplace , attended by the evolution of sulphuret of hydrogen , andleaving an almost black, pitchy substance resembling asphalt .I t i s insoluble in alcohol , but dissolves readily in benzine .

BALSAM .— This term is given to oleo resins which are soft

at ordinary temperatures , and are really a mixture of such aresin and the essential oil o f the plant from which they exude ,such as benzoin , tolu, etc .

BA LSAM O F STORA x (or STYRA X ) .— P roduced f rom the innerbark of a tree of the genus S torax,in A sia M inor. Commer

cially it i s a so ft, coarse, dark- colored powder ; or, more commouly, a semi-fluid , adhesive substance, brown outside, greenishgray inside . The sweet gum of the southern United States isallied to the E astern drug, and was formerly much used inchewing gum. Used in general cements , being particularly goodin leather cements ; also for glass , stone , and earthenwarecements .

BALSAM OF SULPHUR— A solution of sulphur in boilingvolatile or olive oil . Used in certain rubber compounds as avulcanizing agent and a protection against blooming.

B EESWA x i s Obtained from the comb built by honey bees .The crude wax is yellow and soft, with a granular fracturef I ts

specific gravity varies between .965 and .969 , its melt ing pointbeing between 140 degrees and 144 degrees F . I t i s o ften adulterated by water, by white mineral powders , and by cheaper substances, such as vegetable wax , paraffin , etc . White wax is thatwhich has been exposed to the sun or to the moderate action of

B ENZO IN— B I TUMEN 157

nitric or chromic acid, thereby being bleached . I t is sometimesused w ith rubber in medicinal plasters . O rdinary beeswax islargely used in K iel’s hard—rubbe r compounds . Sheet beeswaxis o ften used in the work of vulcanite pattern making. I t isalso used in processes for making fabrics water- repellent

,the

other ingredients being alumina , resin , soap, wax , and silicateof soda . With gutta-percha it is an ingredient in Shoemakers’wax, and also in certain proofing compounds . Hancock used itin a gutta-percha compound for a soft eff ect . In a hard rubbercompound made up of india rubber, sulphur, Oil, and pumicestone, it is said to be acid proof .

BEN ZO I N .— O ccurs in lumps of yellowish brown tears , stuck

together and more or less mottled from the white inside the tears .I ts specific gravity is from to O f an agreeable balsamic odor and very little taste

,but i rritating when chewed for

some time . Used in linseed oil proofings , presumably to killOdor ; also in certain gutta-percha and indiarubber compoundsfor disgui s ing the odors . F our per cent . of the weight of themass is said to be sufficient to make the odor an agreeable one .A ccording to F orster, a little o f it mixed with gutta-perchagreatly improves the quality.

B I RCH -BARK TA R — A pecul iar tar obtained during the distillation of birch-bark ( for oil , being probably the same as Russian jackten extract . Used in the manufacture o f certain rubbersubstitutes . Specific gravity

B ITUMEN .— The term applied to a body made up of severalhydrocarbons . I t resembles Trinidad asphalt and is of the same

nature . I ts specific gravity is from to A rtificiallyit is prepared from shales , mineral asphalt , etc . I t is used as asource o f paraffin . The West Indian product is known as chapapote . A solution is made from it in which the tapes are soakedthat are used for covering wire that has been insulated withindia rubber. B itumen has been utilized by what is known asthe calender process

,which i s a partial vulcanization , render

ing it valuable as an insulator .B ITUMEN

,A UVERGN E .

-A species of natural asphalt foundin the province of A uvergne,F rance . I t is S imilar .to Trinidad

asphalt, but i s impure , containing clay, silica , magnesia , i ron , andtraces of arseni c . See A sphalt .


B LACK P I TCH .- I S the residue left a fter the oils o f tar have

been distilled from that body. Used in weather proofing work.B RITI SH GUM .

- See Dext rine .B URGUNDY P ITCH .

-I S obtained from the hardened juice orsap which concretes upon the bark of the Norway spruce . Specific gravity l .07 A s imported it is O ften quite impure andshould be melted and strained before being used . I t i s almostentirely soluble in glacial acetic acid or boiling alcohol , and somewhat in cold alcohol . When pure it i s hard and brittle , with aShining fracture, dissolves in benzine , acetone, and carbon disnlphide. I S usually reddish or yellowish-brown , aromatic . It i smuch used in cements , in electric tape, and in the manufacture ofporous plasters . Common resin

,i s often melted and mixed with

fats and water, forming a gum that much resembles B urgundypitch .B URM I TE A MBER— F ound in B urma , but quite in ferior in

quality. I t i s a little harder than amber proper, i s easily cut,

takes an excel lent poli sh , but has les s variety of color. See

Amber.BUTTON LA O — See Shellac .CAMPHOR .

—The white transparent substance known bythis name i s obtained from Japan and the i sland of F ormosa .I t i s real ly an oxygenated es sential oi l . I ts spec ific gravi ty i s

Sparingly solubl e in water , and very solub le in alcohol ,ether, acetic acid , and hydrocarbons or volati le oil s . I S largelyused in the manufacture of cel lul oid . Gum camphor i s al soused in compounds of the sub stitute order l ike textiloid ,kerite

,etc . Was a l so the basi s of the heevenoid compounds

(which see ) .

CANADA B ALSAM .—Sometimes cal led Canada turpentine .

It i s derived from the A bies balsamea. Specific gravityI t i s a yellowi sh or greenish transparent l iquid , com

pletely soluble in ether, ch loroform ,

’

or benzol . I t i s sometimes called bal sam of fir

,but i t does not really belong to

the bal sams , being a true turpentine . S trasburg turpentinei s sometimes sub stituted for i t commercial ly . I t i s used incertain compounds to prevent sulphur from effloresc ing . W i thparaffin

,beeswax

,and coloring matters , i t i s used for insulat


and in a measure to act as a S ize , causing it to lie flat. I t isalso said to add strength to it. B y the application of heat, ceramyl

,which comes in the form of a semi- solid , is reduced to a

liquid . In English practice this is said to have driven out theuse of glue in the dressing of elastic webs . Ceramy l is manufactured in England .CERASI N

,also spelled ceresin , i s of a butter-yellow color,

odorless,and has a specific gravity of .918 to .922 . I t is used

chiefly in covering annunciator wires where the obj ect is to preserve the colors of the yarns in the braiding. See O zocerite .CHERRY GUM .

— A pale yellow or red brown gum, comingfrom the bark O f old cherry trees . I t contains 35 per cent . ofceras in

, 52 parts of arab icum , and 1 to 3 per cent . of ash .Thi s gum i s chiefly used in the manufacture and finishingO f fine felt hats . The gums on the market are of two qual ities ,the German , which i s the best , and the I talian . I t i s used ininsulating instead of purified ozocerite , in certain cases wherea l itt le more adhes ivenes s i s required .COALITE P ITCH .

- A residue of coalite tar , much likenatural b i tumen and containing l ittle free carbon . A n Englishproduct .

.COAL TAR— See Tar .

COLOPHAN E .— See Ros in .

COLOPHON Y . —See Ros in .COORONGITE .

-The name given to a rubber- l ike massfound in Coorong , South A ustralia . Some place it among thefos s il res ins . Coorong ite i s not soluble in the ordinary solvents used in rubber work , but after mixing with india rubber ,i t can be put in solut ion . A ccording to F ors ter, i t vulcanizessomewhat as india rubber does . See Chapter I I .

COPAL.— Hard copal i s a fos si l res in ob tained from theE ast I ndies , South America , and the E astern and Westerncoasts of A frica . I t occurs commercial ly in roundish , irreguflar pieces

,having a specific gravi ty of to I t i s in

soluble in alcohol , partially solub le in ether , and s lightly so inoi l of turpentine . Soft copal i s obtained from living trees inNew Zealand , the P hilippine I slands , Java , and Sumatra .Us ed with shellac , asphaltum , and arsenate of potash for

DAMMAR— ELA TERI TE 161

waterproofing leather ; also in cements , in proofing compounds , and in varni shes in connection with india rubber, l ead ,alum

,and other ingredients dis solved in spirit s of turpentine .

DAMMAR i s derived from the A mboyna pine , g rowing inthe M alay peninsula , Sumatra , and B orneo . The res in exudesin tears and is col lected after it has dri ed . I t makes a verytransparent varni sh

,the gum being solub le i n benz ine , essential oi l s

,and to a certain extent in alcohol . Used in artificial

leather compounds , and with rubber, asphalt , and fish oil forwaterproofing l eather. I t i s quite largely used in rubbercements . Specific gravity

DEXTRI N E is an intermediate product between dextrose andstarch . Specific gravity It is soluble in cold water, andis much used as a substitute for gum arabic in mucilage, as it hasstrong adhesive properties . Cooley combined it with a littlegutta-percha, resin oil, and earthy matters in the production ofwhat he called artificial leather. I t is used also in a mixturewith plaster of P ari s

,making a tough surface mold for smal l

experimental rubber work.DEXTROSE i s obtained from starch generally, and is crystal

lized glucose . Specific gravity I t i s soluble in water, andhas many commercial uses . F or example , it was used by Hancock as a sizing for cloth on which was spread rubber in solution, the dextrose being there in order to keep the rubber fromsticking to the cloth . In other words , this was a sort o f cheapcalendering process .

EARTH WAx .—See M ineral Wax .

ELASTI C GLUE is used with india rubbe r and gutta-percha inshoemakers’ cements . See Substitutes.

E LATERI TE is also known as elastic bitumen or mineral caoutchouc . I t appears naturally in soft, flexible masses of a brownisht

black color, somewhat resembling india rubber. It i s composedof per cent. of carbon, and per cent . of hydrogen . In

i t s phys ical characteri stics,elaterite i s found in infinite variety .

It i s sometimes elastic and so soft as to adhere to the fingers ,and sometimes brittle and hard . O ne kind of it, when fresh cut,resembles fine cork, both in texture and color, and will rub out

pencil marks . I ts elasticity is due to its cellular texture, and to

162 GUM S AND B A LSAMS

the moisture with which it combines . I t is used to a certainextent in insulating compounds , but is intractable and so farShows no special features of value above other m ineral s of thesame series . A few years ago a company was formed in Colorado which claimed to be able to make many kinds of rubbergoods from th i s product alone , but l ittle has b een heard of theplan of late . See Gilsonite .

E LEM I comes from the P hilippine I s lands , and i s a resinobtained from certain trees there . I t varies f rom white to grayin color

,and is quite soft and very tough . A lcohol and other

solvents readily dissolve it, and its O ffice usually i s to give toughness to varnishes in which are harder resins . Used in connectionwith india rubber and benzine in the production of puncturefluids . Specific gravity

EUPHORBI UM appears in the market in the shape of tearsof i rregular shape , varying in size from a small pea to l inchesin length . O f a di rty gray or yellowish color, and very largelym ixed with impuri ti es . Must not be confus ed w i th euphorb iarubber (which see ) .

F I CH TELIT.— O 'ccurs i n a peat b ed near Redmitz in the

F ichtelgebi rge in Germany, and also in fossil pines in the formof scales or flat needles . I t has also been met with in F ranzenbad and in Denmark . A hydrocarbon l it tle known

,though

mentioned in certain patented rubber compounds .F I SH GLUE — M ade by boi l ing th e heads , fins

,and tail s of

fish by h igh heat . Specific grav i ty I t i s general ly madeinto a l iquid glue by a treatment with acetic or hydrochloricacid

,whereby its property of gelatinizing i s lost . I t would

have a disagreeable odor were it not for the fact that that i sdestroyed by adding ceros ite or oi l of sas safras or somethingof that kind . F i sh glue i s used in a cement for cured rubb er.in connection with gutta-percha and rubber di s solved in b isulphide of carbon .

F RAN K I N CE N SE .

— A l so cal led olibanum (which see ) .

F REN CH A SPHALTE .- See A uvergne B itumen .

GAMBOGE .— The best i s found in commerce in cylindrical

rol l s of a dul l orange- red color . A nother form i s that oflumps Or cakes . I ts powder i s bright y el low and its taste


to us e , and makes an excel lent waterproof sizing . A mixtureof glycerine with it increases its elast ici ty . I t combines readi ly with glue , dextrine , or any such products , and developsconsiderab le adhes ivenes s .

GLUTEN .— A vegetab le substance obtained from wheat and

other grains . Treated with tannic acid,i t i s us ed as a sub

stitute for gutta-percha under a formula by Johnson,who says

the product can be vulcanized . A nother formula cal ls for i tsmixture with oil and sulphur, as a sub sti tute for gutta-percha .I n cements i t i s the bas i s of one for unit ing leather scraps

,and

i s us ed with a l ittl e gutta-percha .HELEN ITE .

— A nother name for foss i l rubber or elateri te(which see ) .

IDRIALI N (IDRI ALIT) .—A rare hydrocarbon found in I dria ,

a province of A ustria , where it occurs with hepatic Cinnabar .A S imi lar body i s obtained in the disti l lation of amber . I ts

specific gravity i s to M entioned in certain rubberformula s to ass is t the insulating qual it ies of compounds .

I SI NGLASS .— A glue substance prepared from the swim

ming bladders of certain fish . It is white and glistening,occur

ring in fibers or threads . The best i s known as Rus sian , andcomes from A strachan . I ts specific gravity i s O n boiling i singlas s i t i s converted into a very pure form of glue:I singlas s i s us ed in quick-drying cements with ind ia '

rubber ,

chloroform being the solvent .JELUTONG RES I N S .

—Jelutong or P ontianak contains two kindsof res in ; one i s soluble in acetone— easi ly in , hot , l es s eas i lyin cold . A fter 'acetone extraction j elutong when submittedfurther to the acti on of hot or cold sulphuric ether , or othersolvents

,yields the second resin , which is insolub le in acetone .

B oth ' res ins are unsaponifiab le and optical ly active . Theirchemical composition is the same but molecular weights different, as are also thei r melt ing and boil ing points . P robab lythey are secondary ethylene alcohols near ‘

to gum elemi , forwhich they may s erve as sub sti tutes .

P atented solutions of j elutong resin are used as paintthinners and for prim ing coat on cement surfaces , not beingattacked by the cement alkal i .

JUN I P ER— LI THRO -CA RB ON 165

A nother and large us e i s as chief constituent in a composition for coating wire box nail s to cause them to holdfirmly when driven into wood .JUN I PER i s the gum known as sandarac , obtained from anevergreen growing in northern A frica . I t occurs in small ,

l ight-colored grains,with a sl ightly bitter tas te . I t i s soluble

in turpentine oil and alcohol . I s used as an as si stant in making peroxide substitutes . M ixed with rubber and earthy matters and di s solved in turpentine , i t was one of the early compounds for clothing . I ts specific gravity i s to

KA URI . —A n amber- l ike substance varying from a softcream white to an amber color . I t comes from N ew Zealand ,and i s also known as A ustrali an dammar . The l ighter coloredkauri comes from living trees , but much of the darker i s afos sil resin . I t i s cheaper than Copal and largely used invarnishes . Kauri gum ,

. in connection with rubber gum andpitch , i s used for treating yarns used in insulated wire covering s . P arkes added it to rubber goods where the surfacewas to b e printed upon after curing. O ne pound of sulphurformed Richards’s covering for insulated wire. I ts specificgravity i s

LI N I .— A gum made from linseed , often used as a Sub

stitute for gum arab ic . The seeds are first boi led in water foran hour , the result ing thick mass fi l tered , and then treatedwith twice its volume of 90 per cent . spirit s of w ine . A floc

culent white precipi tate separates , from which the di lutespirit can readily be decanted . The gum i s c lear, gray-brown ,fragi le

,and di ssolves in water. Two grams in 30 grams of

oi l i s almost identical with an emul s ion of gum arabic . I n

connection with coloring matters i s thebasi s for the Knowlton patented waterproofing proces s .

LITH RO-CARBON .— A kind of asphalt , large depos it s of

which are found in the state of Texas . It was at one timethought that i t would supersede india rubber, and a companywas formed with the idea of manufacturing goods from it .This was in 1892 , and india rubber i s sti ll used . The chemicalcomposition of lithrO-c'arbon is carbon , hydrogen

,

.06 oxygen , a trace of sulphur. Lithro-carbon i s j et black in

166 GUMS A ND B A LSAMS

color, i s flexib le at ordinary temperatures , and i s qui te tough .I ts specific gravity i s about I t i s 'said to be soluble innaphtha , benzol , bisulphide of carbon , etc . I t will s tand atemperature of 600 degrees F without giving off i ts associateproducts . I t res i s ts alkali es and acids

,with the exception of

concentrated ni tric and sulphuri c acids . I ts manufacture waspatented . Us ed with gutta-percha and shellac it makes anexcel lent insulator.

MA N I LA GUM — See Gum E lemi .MANJAK .

—A kind of asphaltum of which there are extensive deposit s in Trinidad , West I ndies . Us ed chiefly in varnishes .

MASTI C.— A res in from the shores of .the M editerranean .

I t occurs in tears of a pal e yel low , i s b ri ttl e , and of a faintbal samic odor . Specific gravity I t dissolves in acetone ,turpentine oil , and alcohol , and i s largely used in varnish .The residue obtained in the purifying of mineral asphalt isal so call ed mastic . I t i s us ed in general rubber cements forj o ining stoneware

,earthenware , leather, etc . O ne of special

va lue cal l s for 10 parts of mastic to 1 part of india rubber ,dis solved in chloroform , and makes an excell ent cement forfas tening letters to glass . The gum al so appears in many oldfashioned compounds .

M EN THOL is obtained from the oi l of pepperment com ingfrom Japan and China

,or from the oil of spearmint manufac

tured in the United S tates . I ts melting point i s ab out 108 degrees to 110 degrees F . ,

and it i s s lightly so lub l e in water,but freely in alcohol . I t i s often used in medicinal plasterswhich have rubber for a base .

M I N ERAL I NDIA RUBBER A SPHALT i s the name of a materialcomposed of refus e tar produced during the refining proces s oftar by sulphuric acid . I t i s b lack , l ike ordinary asphalt , andqui te elasti c . I t i s an excel lent non- conductor of electricity ,and i s not as sail ed by acids or alkalie s . I n a naphtha solution ,i t yields a waterproof varnish for metal li c obj ects , and i s usedin rubber compounding in place of asphalt .

M I N ERAL TALLOW ,also called hatChetine , i s a sub stance

found in S iberia , Germany , and Great B ritain . I t i s an earth


black wax which , when mixed with india rubber, makes anexcel lent electric insulating material . This wax was recognized by a lecturer before the Society of Chemical I ndustryas the basi s of the insulation known as okonite .

O ZOCERITE .—A waxy hydrocarbon occurring in A ustria ,

southern Russ ia , and the United S tates . I t i s al so known asearth wax. I ts specific gravity i s to and it i s aboutas hard as talc . Chemical ly , i t consis t s of hydrogen andcarbon while it s melting point extends from 140 degreesto 170 degrees F . I t i s often found adulterated with asphaltand sometimes with B urgundy pitch . P urified ozoceri te i sknown as cerasin . To make thi s

,the crude materi al i s

treated with fuming sulphuric acid , and then fil tered throughcharcoal . Thus prepared it i s of a pal e yel low color

,the melt

ing point ranging from 61 degrees to 78 degrees C . I t hasalmost whol ly driven out S tockholm 'tar as a protection forw i res insulated with gutta-percha

,when placed under ground .

I t improves the insulat ion , but in spite of common beli ef tothe contrary

,doe s not preserve textil e fabrics . The best com

pound for the protection of the insulation on wire consis ts of3 part s ozocerit e to 1 part of S tockholm tar . I t i s an insulatorof high qual ity , and wh i le i t i s in some ways intractabl e , it swax- l ike nature allows i t to combine with other insulators orwith texti les . I t i s al so used as a water-repel lent in fabrics ,the gum being volati l iz ed by heat , and the fumes pas sedthrough the cloth . A s a surface covering for tapes or braid ,i t i s often employed and i s better than other gums , as i t takesa fine poli sh from the poli shing machine . The basi s of H en

l ey’s sy stem‘

of curing india rubber core i s melted ozoceri te ,which i s used under pres sure to remove al l the moisture ,being afterward heated in hot ozocerite , which stops up thepores . O zocerite , mixed with india rubber, i s al so the basi sof the india rubber compound call ed nig r ite . I t mixes , however

,w i th difficulty w i th india rubber , which i s an obj ection to

many proposed us es of it . I t also has a mildly deleteriouseff ect on it .

P ARA F F I N .—A white waxy- looking body obtained from

petroleum and certain tars by di sti l lation . I t i s tastel es s ,

P ARA F F IN -P I TCH 169

inodorous , harder than tal low , but softer than wax . I ts spec ific gravity i s .877. I t i s al so obtained from ozocerite orearth wax . I ts melting point vari es with the source it i sobtained from . I t i s insoluble in water and nearly so in boi ling alcohol

,but soluble in ether, oil of turpentine , oil of ol ives ,

benzol , and bi sulphide of carbon . I t i s usually very free fromwater, and not liabl e to absorb it . I t has been us ed as awaterproofing mixture and i s a good insulator . When gos samer cloth ing was manufactured in large quant iti es , the sur

face O f the goods before solari zat ion was covered with a th incoat of parafl‘in, which gave it a pecul iar shade unti l the solar ization was completed , when all traces of the paraffin seemedto di sappear. The in sul ating capaci ty of rubber to whichparaffin has been added is qui te remarkable , but at the sametime i t l es sens the hardnes s of the rubber to a marked degree .Rubber di ssolved in paraffin wax forms a curious compoundwhich has been used in insulation . P araffin i s used in the artificial gums , like parkesine and insulite ; also with cottonseedoi l and res in for cheap bratti ce cloth , and in cheap proofingcompounds . I t i s not a great favorite as an insulator, as itshrinks in cool ing

,caus ing cracks . P araffin tapes are also

easi ly destroyed through the -presence of free acid . I t was

formerly used largely in covering annunciator wires , but asi t was found to ab sorb and retain water

,i t s use was given up,

and its place was taken by a compound of paraffin , cerasin , andresin . I t i s used in some rubber composition s for tubingmachine work to render the stock smooth running and givea fine finish .

P ITCH i s the black residue that remains after the disti l ling of wood tar. Varieties are also obtained from coal tar andfrom bone tar. Wood pitch , however, has a toughness whichthe others do not pos sess . Specific gravity P it chwas used very early in considerabl e quanti ti es in hard-rubbercompounds . Goodyear

,for example

, used considerable of i tin hard compounds for coating metal , the rest of the compound consi st ing chiefly of rubber and sulphur I t i s almostthe only organic sub stance which largely increas es the resiliency of india rubber . I t i s largely used in cements , and al soin many rubb er compounds . E qual parts of pi tch and gutta

170 GUM S AND B A LSAMS

percha make a tire cement for fastening to the rims , knownas “Davy’s Universal Cement .” I t i s used with gutta—perchain Shoemakers’ wax, and also in certain proofing compounds .Wood cements made of gutta-percha as a rul e contain a certain amount of pitch . I t i s al so us ed in the manufacture ofF enton’s artificial rubber.

RES I N S .— The term given to a number of complex bodies ,

general ly the hardened exudation of sap from trees . Chemical ly a res in is the sub stance obtained by the gradual oxidation of an es sential oi l . The specific gravity ranges betweenand Res ins are divided

,as a rule

,into three clas ses

—hard , soft and gum res ins . The former at ordinary temperatures are solid and qui te britt le . They contain l itt le or no ess ential oi l , and are eas ily pulveri zed . Shel lac and sandarac aregood examples of thi s kind

,and soft res ins are usually cal led

bal sams,and are either sem i-fluid , or soft enough to be molded

by hand . They are real ly mixtures of hard res ins , and thees sential o il s found in the plant from which they come . O n

exposure to the air they become in time hard res ins . O f thisclass are balsam of storax, tolu balsam, etc . Gum resins arethe solidified milky juices of certain plants . They consist of amixture of res ins , es sential oil s , and a considerab le proportion of gum . These are , for example , gum euphorbium ,

galbanum , and to this clas s als o b elong india rubber and guttapercha . M ost of the fo ssi l gums , such as copal , are resinswhose phys ical characteri s tic s have been changed by theirhaving been buried for a long time in the earth . These fos s i lres ins are counterfeited to an extent by treating ordinaryres in with l ime

,which rais es its melting point considerab ly .

RETI N ITE .—A l so known as retin asphalt . I t i s a fossi l

resm found in brown coal . I t i s found in roundish masses of ayellow-brown or reddi sh color

,i s quite inflammable and read

i ly dis solves in alcohol . A t present it i s somewhat rare , b uti f i t ever should become common , i t would undoubtedly finda place in rubber compounding. I ts specific gravity i sto

ROS I N i s made from common turpentine , which is di stilled in water

,yielding nearly one- fourth its weight of essential

172 GUM S A ND B A LSAMS

ments broken from the twigs and partly exhausted by water .She l lac i s prepared by melting stick or s eed lac ,

straining,and

pouring upon a flat surface to harden . I t i s then washed ,dried , melted , rough ly refined , and sent to market , or it i spoured into molds to harden and i s known as button or garnetlac . The specific gravity of lac i s about I t i s partial lysolub le in alcohol , turpentine , chloroform , and - ether, and i scompletely soluble in caustic alkalies and borax solutions .Shellac was formerly used very generally in rubber manufaca

ture in surface goods , and particularly in solarized ‘goods insmall proportions . I t has a specific use tod ay in the production of water varni shes for surface goods . I t i s also a con?stituent in the production of certain compounds in hard rubber, and parti cularly the semi-hard variet ie s , being used tothe extent of 20 per cent . of the amount of gum . A l thoughqui te britt le

,i t seems to impart a certain elast icity to the

product . The maximum use of shel lac in a hard-rubber compound

,according to Hoff er, i s 88 part s india rubber, 50 part s

Shellac,and 12 parts sulphur. I t i s al so used in certain of the

Jenkins patented packings to the extent of 10 to 25 per cent .of the amount of rubber , where i t i s said to preserve the compound from the effects of coal oi l

,steam , or hot water. I t

,

i sal so used in many cements both w ith and without india rubber , one formul a for marine glue being : 20 parts shel lac , 12parts benzol , and 1 part india rubber, mixed with heat . Dis

solved in 10 parts of strong aqua-ammonia , i t forms a varnishfor rubber goods , and i s al so used as a solution for re-varnishing old rubber shoes . Used with carburet of iron and b isulphide of mercury as a cement for card clothing, with indiarubber and gutta-percha for attaching shoes to horses , inEngl i sh “ale cement ,” and in certain proofing compounds .

S I ZE — A weak solut ion of glue , sometimes used in shower—proof compounds and cements . The name size i s al so oftenapplied to any thin viscous sub stance , as for instance , gi lders’varni sh . I n rubber practice , however, the glue i s what i sordinari ly employed . I t i s al so used in preparing a perfectlysmooth cloth upon which rubber i s to b e calendered

,and from

which i t i s s tripped before the making up. See Glue andGelatine .

STEARINE—S P ERMA CETI 173

SLUDGE O I L RES I N .—A heavy, gummy residue from the

waste of superphosphate factories . Has been used with rubber in making Japan varnishes .

SPRUCE GUM i s used with chicle in the production ofchewing gums .

STEAR I N E —A white waxy- looking body obtained fromfats— chiefly tallow and palm oil . When made from tallow iti s called pres sed tal low or tal low stearine, which is the sol idpart obtained from the heating of sue t fat and the removalof the liquid part , which is oleomargarine . Tallow stearine i svery largely used in candle making, where i s found saponificdstearine , disti ll ed stearine , and disti l led grease stearine . The

usual specific gravity of s tearine i s .920. This latter containsconsiderab le cholestrol and differs from commercial s tearicac id or stearine chiefly in its phys ical s tructure . S tearine isused in proofing compounds , i n rubber b lackings and in compounds containing res ins . I t has b een suggested that a smal lproportion of stearine in certain rubber compounds that contain low grades of rubber, which in themselves have large proportions of res in , has a decided value in preventing oxidization .

STEARI N E P ITCH .— The brown

,tarry residue left in the

s ti l l during the proces s of refining tallow and fat . Us ed inthe manufacture of certain packings that contain no rubber.S tearine pitch i s al so used as a lubricant for bearings thathave a tendency to heat .

STI CKLAC.—See Shellac .

STOCKHOLM TA R i s used in b lack cements of the marineglue clas s

,and i s al so us ed in rubber compounding, it O ffi ce

being to as s is t in the mixing of dry compounds , and as a binding material for sulphur in the dry-heat cure . Al so used inmanganese cements and in cements to fasten ti les to floors .

SPERMACETI .— A pecul iar fatty concrete sub stance Oh

tained from the head of the sperm whale . I ts specific gravityi s and it i s fus ib l e at 112 degrees F . I nsoluble in water,solub le in hot alcohol

,ether

,and oil of turpentine

,but rede

posited as the li quids cool . Was formerly us ed in certainwaterproofing compos it ions .

174 GUM S AND B A LSAM S

TAR — This substance i s derived from the animal,veg etab le

,and mineral kingdoms . F rom the firs t

,by the d estruc

tive disti l lat ion of bones , i s produced what i s known as “Dippel’s O il” ; from the second , by the disti l lat ion of pine woods ,the product i s knownas pine tar or S tockho lm tar ; and fromthe third , by the disti l lation of coal , i s produced coal tar . O f

the three,coal tar i s the most us ed in rubb er work

,i t s office

b eing to help carry adulterants in dry mixing and to keep thesulphur from bloom ing after vulcanization . I t i s used chieflyin dry-heat work . Goodyear discovered early that very largequantities of boil ed tar could b e us ed in connection with indiarubber and sulphur without injuring the quali ty of the gum ,

and i t has been very general ly used since his time .THUS — A name for gum turpentine , and ranely for ol ibanum . Used with rubber and japan for waterproofing leather.TOLU B ALSAM is derived from a tree found on the moun

tains of Tolu,and the banks of the Magdalena river, in Colom

bia . I t i s very similar to balsam of P eru. I t sometimes appears in commerce in dry friab le fragment s,the newly im

ported gum being soft and tenacious . I t i s very fragrant andhas a medicinal and tonic eff ect . Tolu balsam i s used withparaffin wax and chicle in chewing gum compounds .

TRAGACANTH is an exudation which comes in the form oftrans lucent plates of a dul l white

,which water swell s and

part ly di s solves . I t i s often used in muci lage in place of gumarabic . The gum comes from the Levant f rom the A s tragalusgummifera. Has been used in connection with gutta-perchafor making dental plates that are soft and adhesive to themembranes and that wi l l not rot or deteriorate .

TRAGASOL .— Thi s i s a gum produced from the kernels ofthe Ceratonia s iliqua. The use of this gum as a solvent forindia rubber,gutta—percha , or cel luloid has been patented in

E ngland . A mixture of 25 parts of di s solved india rubber , 75parts of s trong gum solution , with the addition of 1 part ofcarbolic acid to 500 parts of the mixture, makes a cement forwood

,and a preservative paint against insects and verm in .

TRI N IDAD A SPHALT i s obtained from the pitch lakes of thei sland of Trinidad . I ts specific gravity i s and it i s some

CHAP TER X .

P IGMENTS USED IN CO LO RING INDIA RUB B ER .

M OST of the india rubber goods now manufactured areblack

,thi s color, if i t may be so called , being produced in a

measure by the color of the rubber, together with the leadsand other ingredients

,most O f which darken during vulcani

zation. The next prominent color, from a rubber s tandpoint ,i s white

,produced by either an oxide or sulphide of z inc .

N ext to this range the yellows and reds , produced by thesulphide of antimony, vermil ion, and Oxide of iron .

SO many colors are unstab le when brought in contactwith sulphur during the heat O f vul canization , and it i s so difficul t to get good eff ects , that it i s hardly to be expected thatbeautiful colors in india rubber wil l ever become common .There are various methods us ed for changing the naturalcolor of india rubber. The usual way i s by incorporating , bymechanical mixture , earthy pigments or metall i c O xides orsulphides

,or vegetab le colOring matters , which , by their cov

ering property and strength,give to the india rubber their

own particular shade . There are other methods , however.F or example , there have been produced anilines soluble inbenzine , that are used for' surface work, such coloring beingreal ly an elastic enamel . Toys and minor articl es that areornamented in very bright colors , however , are general lypainted over after vulcanization , but paint i s not durab le , nordoes i t long remain beautiful .Whi le i t i s claimed ordinari ly that it i s impossib le to dye

india rubber , i t should b e remembered that the attractivecolors that appear on children’s toy balloons and similar puregum goods are applied as dyes , the colors being anilines , withmethyl alcohol as a vehicle . These colors are boiled in rainwater, and when the solution i s cold the balloons are put intothe 'coloring liquid and turned SO as to have thei r entire sur

176

AN I LINE COLORS 177

face wetted . A fter that,they are dropped into cold water

,

which washes off the superfluous color . When thi s i s doneproperly , the rubber does not give off any stain at al l afterthe first washing . The colors used in thi s way are red

,green

,

b lue, orange , and pink , but other shades are equally available .

Germany produced a full line of anil ine colors soluble inbenzine and for surface coloring of r ubber goods they havebeen found very valuable . A lthough they are not absolute lyfast , they are suffici ently so for al l practical purposes . I n

many cases,these aniline colors , being soluble in benzine, can

b e mixed with india rubber— that is , when it i s us ed in theform of solution . I f the product b e cured in open steam heatwith sulphur, some very curious eff ects are l ikely to beobtained . Thi s was proved at one time when a line of rubbercolors was put on the market in the United S tates , with whiteOxide O f antimony as a base, and anil ines to give variousshades . I t does not often happen , however, that a prob lemof this kind confronts the users of aniline colors in rubber, themore general and sensib le way being that of surface coloring.This is done in some cases by simply brushing the aniline colordissolved in benzine over the surface o f the article . I t i s des irab le , however, firs t to dip the goods in the dis solved mordant

,and then to use the brush , if necessary . Where a high

poli sh or a poli shed effect i s des ired , some sort of elastic lacquer must be put on over the coloring matter . A very thinindia rubber solution i s often us ed for thi s .

In speaking O f anil ines , it must be remembered that thosethat have to b e worked up with acids should b e avoided forrubb er work

,but there are so many others that there i s no

need of the rubber man making this mis take . Where colorsare to be printed upon rubber surfaces , a l ittle dextrine is addedto the aniline dissolved in benzine

,and to make the color dry

faster, a little sulphate '

of manganese mixed with hal f of oneper cent . of alum and added to the mass i s advisab le .

B lack,blue , red , yellow and green anilines are also used

in coloring rubber cements that go to the leather shoe trade .These and other anilines are also used very generally in arti

178 COLORING MA TTER AND P RO CESSES0

ficial leather compounds . A niline black is used in water varni shes for luster coats and blankets .

I t i s also a good idea to sponge the rubber surface with awater solution of alum before the color i s applied . The use

O f alum as a mordant may be supplanted by bi sulphate ofsoda , i f it is desi red . The best colors available in the anilineseri es are reds

,particularly magenta reds , and the marine and

alkal i b lues .A great many methods O f surface coloring have been de

vi sed , some of them being ludicrous attempts at dyeing rubber . The surface of rubber i s , of course , not easi ly aff ected bycolors

, unles s i t has first b een attacked and roughened bysome powerful solvent . M alcolms’ proces s for thi s surfacecoloring is perhaps as harmles s as any . Thi s method is toexpose the rubber to the sunl ight while i t i s immers ed inalcohol . When the surface i s somewhat dis integrated , therubber i s taken out, washed , and dipped in a dye solution .

The colors that fol low are described very bri efly,and any

rubber manufacturer can easily secure most of them for useor for experiment .

BLACK .THERE are more methods of getting black rubbers thanalmost any other color

,as the tendency O f the gum it self i s todarken under heat and the action O f sulphur, and the sulphides

of most material s that are us ed in the compounding have thesame eff ect . M ost rubber goods are made up without regardto color

,and are usually a dirty brownish-black , tempered by

the yellow O f the sulphur b loom . Where a genuine black i swanted

,lampblack i s one of the most common ingredi ents

us ed .B LACK HYPO —Thi s i s al so known as hyposulphite of lead .

I t i s real ly a mixture of thiosulphate of sodium mixed withacetate of lead

,and appears as a fine white crystal line prec ipitate

,which should b e cal led thiosulphate of l ead . There are

two forms, the white hypo and the b lack h ypo , the diff erence

being that the white when heated i s transformed into a softblack powder containing very litt le free sulphur . The b lackof the compound being sulphide of lead O ften contains over

180 COLOR IN G MA TTER A ND P RO CES SEStained on a large scale by co l lecting the smoke produced during the combustion of oi ls , fats , resins , coa l , gas , tar, wood tar,petroleum res idues , dead oil , and even b ituminous coal . Thi saccounts for the various grades that are to be found on themarket . Large quanti ti es of lampblack are manufactured fromnatural gas and known as carbon or gas black . There aremany types of lampblack , the best in the world being employed in the preparation of india ink . Thi s i s made fromburning camphor, a lower grade being made from the mixture of camphor and other O i l s . The smoke i s col lected onleaves

,washed

,dried , and s ifted with the utmost care .

The l ines of rubber goods in which lampblacks are generally found are rubber boots and shoes , black automobi letreads

,surface clothing

,and carriage cloth , druggi sts’ sun

dri es (where the leads are deemed dangerous ) , and in certaincompositions where emery is the chief ingredient used for grinding or pol ishing . A curious fact about lampb lack i s that alit tle b it of i t i n unvul canized rubber seems to as si st theeras ive quali ty, and does not caus e smutting. A l i ttle of it i sal so sometimes added to churning mixtures that do not readi ly mix .

LEAD SULPH IDE —This is a valuable coloring matter forrubber, as i t gives a good black , bes ides which i t makes goodsexceedingly resil i ent . There are great diff erences in the production of lead sulphides , but a good one i s O f special valueto rubber manufacturers . Specific gravi ty

P ARI S B LACK .— See Carbon B lack .

S ATI N GLOSS B LACK .— See Carbon B lack .

S I LI CATE O F CARBON .— See Carbon B lack .

URAN I UM SULPH IDE — A fine black pigment more intensethan plumbic blacks . I t i s a permanent color, and i s said tobe a preservative of rubber .

BLUE .

B LUES are not largely used in general rubber work . Theyare found chiefly in toys , in sheet ings , and in certain packings .

CHROME B LUE—SA X ON B LUE 181

CHROME B LUE i s manufactured from sil ica , fluor spar, andchromate O f potash . The resultant material i s a deep b luevitreous mass which i s reduced to an impalpable powder . I t

i s l es s sensit ive to acids than ul tramarine , and i s b etteradapted for rubber goods .COBALT B LUE i s manufactured from oxide '

O f cobalt , phosphate O f cobalt , and alumina . I t i s rarely used in coloringrubber where the ingredients are to b e mixed with the mass ,ul tramarine being much superior. A l so cal led s r'nalts .

I NDI GO BLUE is prepared from plants O f the I ndigofera genus .P ure indigo i s insoluble in water, nor i s i t soluble in weakacids or alkal ies . A

‘smal l percentage i s dis solved in alcoholand its solution i s more considerable in turpentine . I ndigob lue for rubber i s said to be valuab le on account of it s 'pres erving qual iti es , wh ich are double thos e of other b lues . I ts

specific gravity i s ' 1.35.

M OLYBDEN UM B LUE — A pigment recommended by -Lascel

leS -Scott i s a bi sulphide of molybdenum . I t i s an exceedinglybeautiful b lue, but costly . Large new deposit s O f this mineralhave been found in the United S tates and A ustral ia

,and Nor

way , and it i s l ikely to be so cheapened that i t wi ll b e a valuabl e rubber pigment .

P RUSS I AN B LUE (Known also as Chinese blue ) . —A dark,b r il liant

’

b lue compound , having iron for a base . There i sa solub le and an insolub le variety of thi s compound which i sof a somewhat complex chemical constitut ion . Heatedstrongly in the ai r

,the insoluble form '

of P rus sian b lue burnslike tinder . When boi led wi th caust ic potash , i t i s decomposed . I f the d ry powder be strongly rubb ed '

in a mortar, i tassumes a Copper- red luster. In commerce it occurs in irregul ar shaped masses , having a character istic ‘

conchoidal fractureand Copper- red luster.

SAXON B LUE i s the original name 'of the pigment knownto- day as smalts ; it was also very frequently cal led enamelb lue . Under th i s name was al so Sold a b lue 'pigment made bymixing P russian blue with alumina or a white c lay .

Q

182 COLORING MA TTER AND P RO CESSESSM A LTs .

— This _ i s what may be called a deep tinted cobaltglass . The analys i s of smalts of good qual ity is as fol lows :Deep PaleColored Colored

Norwegian German

S i l ica 72 . 1P otassa (with traces of soda and l ime)O xide O f cobalt . .

A lumina 4P eroxide of iron .3Other earths and oxides , and loss

TotalThi s i s one of the few colors that are practi cally inde

structib le . I n us ing smalts for the pigment , large quanti tie sare necessary , as the color i s not strong.TH ENARD

’S B LUE i s s imi lar to cobalt b lue

,but i s a more

beautiful pigment . I t i s used chiefly as a surface color . Whitepigments in smal l quantiti es added to thi s b lue make beautiful turquoi s e colors .

ULTRAMARI N E .—This i s the most important b lue used in

rubber. I ts composition is es sential ly the same whether genuine lapis lazuli or artificial . A rtificial ultramarine is equal andO ften superior to the natural pigment . Thi s is made of kaol in

,

carbonate of sodium , willow charcoal , and sulphur . The following analys i s of the natural ul tramarine i s given

A nalyses of the bes t artificial ul tramarines show thesefigures

S i l icaA lumina 26 62 24 40 25 85SulphurSoda

Ultramarine appears in commerce as a fine blue powderof various standards of finenes s . A cids readi ly destroy i t , butalkali es have no eff ect on it . I t s tands heat well , not chang ingbelow a low red . I t i s used in cements for backs of memorandum blocks , and in b lue soft rubber goods , particularly invapor- cured goods

,such as sheeting . When mixed with

chrome yellow it makes a green ; with colcothar, i t makes a

184 COLORING MA TTER A ND P RO CESSESNo . 2

S i l icaA luminaP rotoxide of i ronMagnes iaSodaWaterULTRAMARI N E GREEN i s made by a proces s very similar to

that made in producing blue O f that name , and i ts action upon rubber i s almost identical with that of ultramarine blues .RED A ND BROWN.

TH E strong red coloring matters used in hard rubberwork are mostly of a mercurial base . These are vermil ion

,red

chromate of mercury , sulphide of mercury , and iodide O f mercury . The Chinese vermilion , which i s the best , i s preparedby a special proces s of thei r own , and contain s 89 per cent . ofpure mercury , the res t b eing sulphur . Thi s coloring matteri s used very largely in dental vulcanite , small amounts of ital so giving excel lent shades in soft rubber goods . Cinnabarand P ari s red are al so mercurial sulphides , and very strongcolors . The sulphides O f mercury are real ly the only onesthat are safe and valuable for producing these colors . Red

chalk and natural clay containing a certain amount of i ronare us ed chiefly as fill ers in rubber goods , al though a certainquantity of them produces a dark red color.

A NTIMON Y CRI M SON SULPH IDE — Thi s i s altogether thebest antimony color now in us e . I t gives a fine Shade oforange or red . Specific gravityCOLCOTHAR.

—A form of oxide of i ron of specific gravityto I t i s the acid f ree calcined residue of iron pyrites

f rom the manufacture of sulphuric acid . The least calcined portions

,scarlet in color

,are termed j ewelers’ rouge , and the more

calcined parts,of bluish shade

,are called crocus . I ts compOsitiou i s ferric oxide . In its reaction it is indiff erent , being very

stable under ordinary conditions . Colcothar is a dull red andis often used in red packings, solings , etc .HEMATI TE .

— A n ore of iron , somewhat soft and friab le .Specific gravi ty to Composit ion 70 per cent . iron ,

INDIAN RED— VENE TI A N RED 185

30 per cent . oxygen . I nsoluble in water , alcohol , or rubbersolvents . A S a colorant in rubber work it i s unchangeableChemically . Used in pack ings and for red maroons .

I NDI AN RED.

-A deep rich i ron oxide red,made in di f

ferent shades and purities .IRON O X IDE — P ure bright iron oxide , made by calcining

i ron sulphate . I t contains 96 to 98 per cent . i f i ron sesquioxide ,the remainder being silica . The cheaper grades sometimes contain water of crystallization . The better grades are prepared bywet grinding in buhr and pebble mills . See ColcOthar .

I RON P EROX IDE — A n O ld name for the sesquioxide of i ron .O RANGE VERM I LI ON , crystall ine lead chromate , gives a

very handsome color in connection with rubber, but i s rarely

used,as it i s not permanent if other metals

,such as copper

,

bras s , i ron , and zinc , come in contact with it . Specific gravi ty

O X I M ON Y .—A special brand of red oxide of iron for the

rubber trade . I t has about four times the color strength ofsulphuret O f antimony .

P RI N CE’S METALLI C P AI NT.

— A n impure Oxide O f i ron ofvariab le analysi s containing much si l ica and alumina .

P RUSS IAN RED i s an oxide of iron prepared from copo n lperas , and , therefore , I t . i s the same as the modern rouge or

oxide O f i ron .RED O

'

CH'

ER .—A n impure oxide of iron . A dul l- red earthy

substance containing clayey matter,and having a specific

gravity of about Us ed chiefly as a fil ler,as the color i s

not strong . A s far back as the time of Dr . M attson , red ocher ,V enetian red

,and I ndian red

,were advised by him for use

in rubber compounding. I ndeed,he obtained a patent for

packing in which V enet ian red was the principal adulterant .VEN ETI A N

'

RED.-The usual composition of V enetian red

i s a comb ination O f ferri c oxide and calcium sulphate in theproportion of 20 to 40 per cent . of the former to 60 to 80 ofthe latter . I t i s made in the dry way by heating ferroussulphate with l ime . I t i s inferior in pigment effect to ordinaryiron oxide . The color i s dul l brick-red .

186 COLORING MA TTER AND P RO CESSESVERM I LI ON .

-The red form of mercuric sulphide i s a scar~l et red powder of specific gravi ty I t i s sometimes adulterated with red lead or red oxide of iron

, but such adulterations can b e detected by heating a smal l sample of the suspected article on a porcelain or platinum dish . I f any adulterant i s present it will remain behind as a res idue

,s ince pure

vermilion is completely volat i le . This substance i s sometimescal led Cinnabar. A substitute for vermil ion in hard rubberwas brought out by John Haliday in 1870. Thi s was a mixture of garancine and cochineal , in water solutions , boi led andmixed in the proportion of 5 parts of garancine l iquor to 1part of cochineal l iquor. To each gal lon of thi s compoundl iquor 2 pounds of pure Oxide of antimony were added ; thenheating unti l the water was . evaporated and the new coloringmatter perfectly dry . A nother vermilion sub stitute wasantimony crimson sulphide . A ccording to A . D. Schlesinger ,veteran hard rubber expert , antimony crimson sulphide ,when mixed with india rubber and sulphur

,will , during vul

canization, impart to hard rubber a light red color very S imilar to that Obtained by the use O f vermil ion . The proportionof sulphur i s the same as i s used ordinari ly in making vulcamite

,while to each pound of rubber are added 12 ounces of

crimson sulphide O f antimony.WH ITE .

O N LY a few colors are avai lab le for use in making whiterubber goods . O f these , the z ines take the lead , b eing by farthe most constant and valuable . They lend their color to themas s simply by their presence as dry paints with strong coloring quali ti es .

B ARIUM WH ITE — This i s al so called constant white , orblanc fix e, and comes f rom the sulphate of barium or heavyspar . I n treatment , i t i s ground very fine , treated with hothydrochloric acid

,washed

,dried , s ifted , and then forms a

fairly white,dense

,impalpab le powder. A rtificial barium sul

phate or blanc fir e is obtained by precipitation from a solutionof barium chloride with a solution of sulphate o f soda . I t is ident ical with the mineral baryte s in al l of its chemical propertie s .I t i s a bri l l iant white O f exceedingly fine grain . I t i s hi ghly

188 COLORIN G MA TTER A ND P RO CESSESin rubb er compounding. I t i s not eas ily aff ected by atmospher ic i nfluences , or bv the action of sulphurous compounds .

F ULTO N WH ITE — S ee Lithopone .GRI F F ITH’S WH ITE i s a sulph ide of zinc of E ngl i sh manu

facture , prepared by precipitation , and containing a certainproportion of magnesia .

KREM N ITz WH ITE was the name of a somewhat indefinitewhite . I n some cases i t was appl ied to white lead

, but inothers was given to b ismuth white (Oxide of b i smuth ) andoften to white oxide of t in .

LITHOPON E (also LITHOPHON E ) .— A white pigment made

by precip itating sulphate of zinc with barium sulphide . The

barium sulphide i s made from the native barytes by heatingwith charcoal

,which reduces the sulphate to sulphide and

polysulphide,which are soluble in water. The zinc sulphate

i s made by roasting z inc b lende or the ore “black j ack” underoxidizing conditions , which forms soluble sulphate O f zinc . B othsubstances are dissolved in water, which frees them from manyimpuriti es , and the two solutions mixed , when zinc sulphideand barium sulphate both precipitate out as fine powder mixedwith free sulphur from the polysulphide . The powder i s dri edand roasted , which drives O ff free sulphur and produces somefree zinc oxide . Gives a fine white , but may turn gray onlong exposure to light. This defect is not SO bad for rubber asfor painting. I t i s a constant white , and i s largely us ed instead O f oxide of zinc for white goods , particularly in themanufacture of druggist s’ and surgical sundries . The commercial article contains 70 per cent. of barium sulphate and30 per cent . sulphideof zinc . I ts Specific gravi ty is to

M OUDA N WH I TE OR MORAT WH ITE —'

This white camefrom the P ays de Vaud in Switzerland , Moudan and M oratb eing two towns in that di strict . I t was a fine white clay witha silky luster and a fine grain . I t resembles Spani sh whiteand was often us ed in place of i t .

O LEUM WH ITE — A high grade of sulphi de of zmc,In

which is a certain proportion O f blauc fixe. I t is a trifle beavier than a pure sulph ide of z inc , but in practice has been foundto be equal to if not b etter than either the sulphide or oxide

P ON OLI TH— ZIN C OX IDE 189

of z inc in the manufacture of certain white rubbers . I t i ses sential ly l ithopone .

O 'RR’S WH ITE — See Li thopone .

P O N OLITH .—A nother name for Lithopone .

RO SS’S WH ITE — See Lithopone .

ROUEN WH ITE was a marly clay found near Rouen inF rance , prepared for us e by levigation . I n most respects itresembles B ougival white .

RUBBER MAKERS’ WH ITE — A nother name for Lithopone .S PAN I SH WH ITE i s a name now O ften given to a good

qual ity o f whiting, but originally given to a good kaolin clayprepared for sale firs t by levigation

,then by treatment with

vinegar, which separated out any calcium carbonate it contained , then washing wel l and drying .

TROYE’S WH I TE i s a carbonate of l ime , and , therefore , wasin all respects like the modern whiting. I t was a very commonpigment at one time and much used for a variety of purposes .Specific gravity about

ZI N C CARBONATE — This is a form of zinc rarely knownto—day in rubber m i l l s . The firs t white rubber, however, wasmade O f i t under a patent granted to the late Henry G. Tyer.I t is a white powder, O f the specific gravity O f and is made bymixing a solution O f equal quantities o f sulphate o f zinc and carbonate of sodium, and Subsequently the boiling of the whiteprecipitate formed for a short time .

ZI N C O XIDE i s used more than any other coloring matter inthe production O f white rubber. I t is especially valuable becauseduring the process O f vulcanization it increases the whitenessof the goods . This is because the part of the zinc oxide that i sturned into the zinc sulphide is a stronger white than the first .O xide of zinc made of pure spelter i s the best . Where lead andzinc ores are found together i t sometimes happens that theoxide contains a certain amount of lead , as lead sulphate , andthen its value as a coloring matter i s injured .

Zinc Oxide is prepared by two processes : F rench process ,in which spelter or metallic zinc is the raw material , andAmerican process , in which ores of zinc a re the raw materials .

190 COLORING MA TTER AND P RO CESSESF rench proces s oxides of American manufacture are knownas “F lorence z inc .”

F rench process zinc oxide is sold in three grades , designatedas White S eal ,” “

Green S eal” and “Red S eal .”

White Seal i s bril l iantly white , of large volume and extreme finenes s . I t weighs 150 pounds to the barrel , as compared with 300 pounds of other oxides .

Green S eal i s equal in bril liancy O f color to Whit e S eal ,but i s les s voluminous .

Red S eal i s the cheapest O f the three grades and is neitherso white nor so smooth in texture as the others .

A merican proces s zinc oxides for the rubber trade are oftwo brands , “

Special” and “X X Red .

”

Special i s part icularly free from lead , containing les s thanper cent . of protoxide . I t i s i ntended for use in com

pounding white rubber and can be used in any mixture without changing color . I t i s very smooth and free from mechanical impurit ies .

X X Red i s an oxide for mechanical rubber goods , freefrom mechanical impuriti e s . I t contains up to ‘ per cent .of protoxide of lead and i s not so white as the “

Special”brand . The specific gravity of z inc

‘

oxide i s I t i s sometimes known as Chinese white . A certain percentage O i thisoxide is O ften added to dark-colored good s to increase the resiliency of the rubber. I t also increases the hardness of a compound where soft gums are us ed . M anufacturers in insulatedwire find that it increases the insulating qualities of rubber whenadded in moderate quantity.

A very simple test for zinc oxide is as follows : P ut a smallquantity in a test tube or vial and add diluted muriatic acid(such as can be obtained in any drug store ) agitate to dissolveall lumps, and i f it be commercially pure Oxide O f zinc , no residuewill remain . The only adulterant likely to be found which wouldnot leave a sediment would eff ervesce violently. Should theaddit ion of acid to the pigment produce sulphureted hydrogen ,the odor of which i s unmistakable

,no doubt would exist that the

sample is not oxide of zinc and probably a much cheaper pigment. There are many pigments on the market called zinc andcontaining some zinc in various forms

,which have their uses ,

but should not be confused with straight oxide of zinc .

192 COLORING MA TTER AND P RO CESSESrubber. O n account of its poisonous properties , this yellow hasbeen largely superseded commercial ly by the comparativelyharmles s chrome yel lows . A nother name for this color

,i s

orpiment . I t was often used in rubber compounds O f twentyyears ago . A small quantity in wh i te z inc s tock takes O ffthe glaring white eff ect , and produces a handsome creamwhite . I t must be an impalpable powder to bring out the color.

A UREOLI N .-A very handsome color

,and one that i s s tab le

and bri l l iant . I t i s a double nitrite of cobalt and potas s ium .

The color stands the light wel l , and ~ sulphur compounds havel i ttl e influence upon i t . This i s chiefly used for surface work .B ARBERRY Y ELLOW .

—M ade from the root or bark of theB arber is vulgaris . It i s largely used in coloring leather surfaces ,and

,in connection with gamboge , i s said to be useful in rub

ber work .CADM I UM Y ELLow.

— This is cadmium sulphide and is thebest pigment for producing yellow in a rubber compound . I t doesnot injure the elasticity or strength of the india rubber in anyway

,and , whi le i t has no special eff ect on vul canization , per

haps hurries it a l itt le . I t i s not injurious to the health ofpersons using it , and i s general ly used for surface ornamen

tation of toys , etc . I t i s sometimes mixed with yel low sul

ph ide of tin to cheapen i t . Whil e cadmium was ruled againstin the German anti-poison act , the sulphides of thi s , metalwere made an exception and said to be safe . I n dental plates ,however

,where the coloring matter was used in large quan

tities , it was advised against. The costliness of cadmium yellow bars its general use in rubber. I ts specific gravity isCHROME Y ELLOW .

— O rdinarily the chomate of lead , whichis largely used as a pigment . I t i s somewhat poisonous and isapt to oxidize organic substances , particularly i f sulphur be present . Has been used in the surface ornamentation of rubber toys ,but such use i s generally condemned . The only chrome yellowsthat are really valuable for rubber work are the chromate of zinc ,or possibly the chromate of strontium .

COBALT Y ELLOW .— This is another name for aureol in .

DUTCH P I N K is the name gi ven to some common yellowlake pigments made from P ersian berries,quercitron bark , fustic ,

G‘

AM B OGE —ZINC YELLOW 193

etc . , on a base of China clay or Whiting. A t one time a blueDutch pink was known , prepared from the woad plant.

GAMBOGE Y ELLOW .— O btained from the Garicim'

a mor ella.

I t contains from 20 to 25 per cent . of gum, 65 per cent . of resin ,3 per cent . of volatile oil . I t i s soluble particularly in spi rits , ina number of O ily liquids , and partially in water. F inely pulverized gamboge may be mixed with rubber, and is said to be apreservative o f it .

Y ELLOW OCHER.— There are several Ochers , all of them

being practically oxides of iron mixed with clay. They are earthysubstances of no particular reaction , very stable , having a specificgravity o f about Their low cost renders them availablefor almost any work , but the colors produced are not especiallybeauti ful .

ZI N C Y ELLOW — Th is color is chromate o f zinc and potassium . I t is o f l ight lemon color and permanent . I t is not aff ectedby sulphur and can be mixed with other pigments .

CHA P TER X I.

A CIDS ,A LKA LIE S ,

A ND THE IR DERIVATIVE S USED

IN RUB B ER MA NUF A CTURE .

A s a rule neither acids nor alkalies , in the strict sense of theterm

,are largely used in ordinary rubber compounding. In a

great many of the proc esses , however, that go far to make upfinished goods , acids are used , as , for example , in those employedin the reclaiming of rubber chemically. A lkalies also are mostnecessary

,a notable example being the use of caustic potash and

caustic soda solutions in removing sulphur f rom manufacturedg oods . A great variety of uses other than these may be indicated .

A CETI C A CID— Th is i s usually obtained by the dry distillation of wood

,peat , or sawdust . The strongest form is known

as glacial and occurs in large watery crystals , readily liquified .

The common commercial acid usually has a brown or yellowishcolor

, due to impurity. The pure acid is colorless . I ts specificgravity is and it has the characteristic Odor familiar invinegar. A s an acid it i s not very corrosive

,and its compounds

are easily decomposed by mineral acids . I t i s quite volatile .The primary use of this acid in connection with india rubber isin the coagulation of rubber milk . I t i s a prominent componentpart of the smoke used in coagulating fine P ara rubber . It hasalso been used in the Vaughn process for coagulating balata ,and in the manufacture o f certain substitutes l ike linoxin , parkesine , etc . ; in connection with nitro-cellulose and castor oil inthe production of certain waterproofing compositions ; by B rooman in separating whiting, white lead oxides , etc ., from vulcanized rubber ; and in shoemakers’ blackings in connection withcaoutchouc O il , vinegar, molasses , and lampblack .

A LUM .—A general term for several chem ica l compounds

of aluminum , potassium ,chromium ,

and ammonium. Com

mon alum i s the doub l e sulphate O f potassium and aluminum ,

194

196 A CIDS A ND A LKA LIES

compounding sponge rubbers . Use I n l inseed O il compounds ,for wagon covers . See A lum .

A MMO N I A,at ordinary temperature , i s a colorless gas of

well-known Odor and sharp , biting taste . I t i s usually met within the arts in watery solution

,the specific gravity O f which varies

with the amount o f ammonia gas dissolved . The strongest,sometimes called caustic ammonia , contains per cent. of thegas

,and has a specific gravity of .875. O rdinary commercial

ammonia contains per cent . ammonia gas and its specificgravity is The weakest usually : has a percentage ofand a specific gravity of .978. Ammonia has a powerful solventaction upon sulphur, i s alkaline in ‘

its nature, and very volatile ,so that much care is requisite in handling it . It has long beenknown to have a preservative effect upon india rubber ; for example , low grade A frican rubbers are O ften treated withammonia to neutralize the smell , and also to toughen the rubbe r.In the cold-curing process a saucer of ammonia put in the bottom o f the vapor room will effectually neutralize the fumes ofchloride of sulphur. It i s also advised to wash with an ammoniasolution vulcanite that has begun to perish . Soft rubber goodsalso are preserved , according to Dr . P ol , by the immersion foran hour in a solution made of 1 part o f ammonia

,and 2 parts

of water.S ievier dissolved india rubber in ammonia , leaving it in a

closed vessel for a long time , after which he heated the solutionand absorbed the ammonia gas in cold water. Concentratedliquor of ammonia is added to milk of the rubber tree to preserve it for transportation . Where vegetable fibers are reducedto cellulose and mixed with india rubber, the rubber is firststeeped in ammonia and then dissolved in some suitable solvent.N ewton mixed ammonia with india rubber and gutta-percha, ‘

and

then treated the gum with chlorine , making a white , hard compound , which he claimed would stand all varieties of climates ,acids , greases , etc .

A MMON I UM CARBONATE , obtained during the dry distillation of coal in the manufacture of illuminating gas , i s a whitecrystalline powder of very penetrating smell

,from which quality

it takes its popular name of smelling salts . Exposed to air, itdecomposes , evolving ammonia and becoming conver ted into

AMM ON IUM CHLORIDE— AN ILINE 197

bicarbonate . I t i s used industrially for the r emoval o f greasefrom cloth and cleaning woolen fabrics . Carbonate o f ammoniais used also in the manufacture o f sponge rubber, and in hollowwork, where its expansive force is util ized to mOld the articleeffectually.

A M M ON IUM CHLORIDE .—A lso known as muriate O f ammonia ,

or sal ammoniac . O btained largely f rom gas works liquor. Spe~cific gravity Usually occurs in small crystals . When dissolving in water a considerable reduction of temperature occurs ,and this has rendered it valuable for cooling purposes . A t

temperatures above 212 degrees F . it i s completely evaporated ,and a decomposition into ammonia and muriatic acid occurs . I t

i s used in certain pack ings in which iron filings are incorporated .A MMO N I UM TUN GSTATE .

—A crystalline body which is verysoluble in water and becomes covered with a white bloom orefflorescence on exposure to the air. Used with boracic acid

,

kauri , borax , and rubber in the production of the wood ite fireproof composition .

A N I LI N E .—A n oily l iquid , colorle s s when pure but ordi

mari ly straw color . I ts specific gravity i s at 60 degreesF . and i ts boi l ing point degrees F . Commercial ly , anil ine i s O btained by a series of chem ica l transformations , beginning with coal tar. Among the products l iberated fromcoal tar by di sti llation I s b enzol . B enzol , when acted uponunder suitable conditions with mixed nitric and sulphuricacids , i s converted into nitrob enzol . N i trobenzol may furtherbe acted upon and chemical ly “reduced” to ani l ine oi l bytreatment with dilute hydrochloric acid in the presence of a slowfeed of common cast i ron borings

,both acid and borings being

in definite proportion to the charge of nitrob enzol to bereduced . I f sold as pure ani l ine should not contain over onehalf O f one per cent . of water , and should be free O f nitrobenzo l . A delicate tes t for the presence of nitrob enzol i n ani l ineoi l i s to shake a sample violently for a few minutes , and noticethe color of the froth so produced . The merest trace of nitrob enzol present will give a very distinct yellow coloration .

In recent years the use of aniline in the ”manufacture o frubber goods has increased to large proportions . The chie f

198 A CIDS AND A LKA LIES

function of aniline as a compounding ingredient is that it servesas a catalyser

,accelerating the combination o f sulphur and rub

ber in the process O f vulcanization . I ts use i s accompanied bya considerable degree of danger to the health o f the workmenunless adequate measures are adopted to prevent its fumes beinginhaled or the liquid coming in contact with the skin

,through

which it is readily absorbed .A n Amerc ian process for reclaiming waste vulcanized rub

ber calls for its admixture with aniline oil and Subsequent steamdevulcanization .

A niline was used by P arkes in the manufacture o f parkesine .

I t is 'also a solvent for gutta-percha and in the laboratory is usedin analytic work as a solvent for vulcanized rubber.

The so-called aniline dyes are derivatives of aniline .A N TI MONY I ODIDE .

— A brownish- red crystall ine mass , whichyields a cinnabar- red powder. I t i s soluble in hot carbon bisulphide . I ts specific gravity i s I t was used by P arkes invulcanizing india rubber.

B ARI UM CHLORIDE — A white crystalline powder. I ts spec ific gravity is To makers and users of sulphurets itaff ords a ready means of determining the presence of free sulphuric acid , so liable to occur in these bodies and so injuriousto rubber compounds when present. A suspected sulphuretshould be boiled for a moment with a little distilled water

, the

water filtered off , and a drop or two of a solution of bariumchloride added ; a white cloudiness that will settle in the formO f a White powder proves the presence o f sulphuric acid and sucha sample should be rej ected . B arium chloride is a powerfulpoison . Used with size and acid resin as a shower-proof mixture .

B LEACH I N G P OWDER OR CHLORIDE O F LI ME i s a mixture ofthe chloride and hypochlorite o f lime . Industrially, its chie f usei s for bleaching purposes , dependent upon the amount of chlorineit contains . Commercial bleaching powder is a white powderwith a smell o f pecul iar character (chlorine ) and gradually becoming moist on exposure to the ai r, while it gradually decomposes and absorbs water and carbonic acid . Even in closed vessels decomposition occurs , and sometimes so suddenly and withsuch a rise o f temperature that explosions occur. Hence itshould always be used f resh and a guarantee obtained from the

200 A CIDS A ND A LKA LI ES

the“

O rinoco CO ., in Venezuela . I t has also been used in connection with a little ammonia to increase the elasticity of lowgrade A frican gums , being used as a solution be fore the gumsare washed . I t is also used for treating fabrics

,such as hose

l inings for fire and mill hose, to prevent deterioration and rotting. Used in certain fiber—made substitutes and in a rubberreclaiming process .CATECHU OR CUTCH .

—Known formerly as j apan earth .M ade from the sap of an E as t I ndian tree , and used chiefly indyeing. I t i s very astringent , and i s soluble in water . I t

appears in commerce in dark-brown irregular lumps . Con

tains 40 to 50 per cent . of a pecul iar tannic acid . Used inpack ings and goods made from the whale ite formulas . Johnson’s artificial leather was made of catechu

,ros in oil

,l inseed

O i l , turpentine , and starch ,m ixed with a l ittl e hot gutta

percha . A number of other compounds,both with and with

out india rubber, contain catechu ,but chiefly those which were

compounded from gelatine,starch

,and gluten . Catechu i s

m ixed with gutta-percha in solution in order to make i tharder .CHLORIDE O F LI ME— See B leaching P owder.CHROM I C A CID i s not readi ly obtained in a free state

,but

forms many well-known salts , such as chrome yellow (leadchromate ) , for instance . Chromic acid i s analogous to sulphur ic acid . Vulcanized rubber immersed in it at 140 degrees F . remained a month ,

and was apparently unharmed .I t i s a l so used in the manufacture of the sub stitute known ascorkaline .

CI TRI C A CID— A n organic acid that occurs in lemons , l imes ,and other citrous fru its . It i s readily soluble in water . Has

been used in the coagulation of balata . Vulcanized rubber immersed in it at 140 degrees F . remained a month , and was apparently unharmed .COPPER SULPHATE .

—Sometimes called blue or Cyprus vitriol . O ccurs in commerce in masses of large blue crystals having a specific gravity of and containing 36 per cent. of waterof cry stallization, and a vary ing additional percentage of entangled moisture . Heated for some time at 212 degrees F ., all

F ORM I C A CID— HYDRO CHLORI C A CID 201

the entangled water may be driven O ff , together with four-fifthsof the water of crystallization“

,the residue being a bluish-white

powder. Sulphate of Coppe r solution is used in copper platingi ron for secure attachment of rubber by vulcanization .CREAM O F TARTAR.

- See P otassium A cid Tartrate .CUTCH .

— See Catechu.

F ORM I C A CID obtains its name from the fact that it was firstobtained from the red ant . It is a fuming liquid with a pungentodor, boiling at 212 degrees F . , specific gravity I t i s nowmade from a mixture of starch , binoxide of manganese , sul

phur ic acid , and water. I t has been suggested as an ideal prec ipitant for rubber milk . I t i s quite volatile , could be easilywashed out, and would be found more beneficial to the rubberthan many of the alkaline solutions now used .HYDROCHLORI C A CID i s known usually by its trade name of

muriatic acid . I t is one o f the principal mineral acids and acommon reagent in chemical analysis . Used in the arts in theform of a water solution , of which the strength varies from aspecific gravity of or 2 degrees B eaume with per cent.acid to or 26 degrees Beaume, with per cent. acid .E ach .01 increase o f gravity corresponds to 1 degree B eauméand per cent . of acid . I t i s corrosive to the skin and attacksnearly all metals . It has no action on caoutchouc and very littleon oxidized linseed O il i f the acid be dilute . With soda it formscommon salt and with metals it forms chloride thereof . Hydrochloric acid , during the treatment of reclaimed rubber, turnswhiting into calcium chloride . A s the chloride is more solublethan sulphate of lime, much of it washes out during the vigorouscleansing that the rubber undergoes to remove the free acid .Hydrochloric acid , according to tests made by William Thompson , did not at all injure india rubber, although it waskept in it at a temperature of 140 degrees F . for a month . Concentrated hydrochloric acid has‘ but l ittle action on gutta-percha ,and tubing made from it i s there fore largely used in chemicalfactories for running this acid f rom one vessel to another.Hydrochloric acid is used in the manufacture of synthetic rubber from isoprene .


HYDROGEN P EROX IDE — This is a powerful oxidizing agent,large ly used as a bleaching agent , and also for neutralizing afte rchlorine bleaching. I t comes in the form of a colorless l iquid ,and has a Specific gravity of N either the alkaline nor theacid solutions o f this reagent seems to impair vulcanized indiarubber. In certain cases peroxide of hydrogen has been used inremoving the bloom from rubber

,which it does most effectively ;

besides , it seems to penetrate the surface of the rubber and dissolve the sulphur . I t also has a curious eff ect on colors , brightening some reds wonderfully , dulling others , and renderingwhites much whiter. O ne curious eff ect that it has upon indiarubber is to bring out any sur face imperfections to a markeddegree .

LEAD A CETATE OR SUGAR O F LEAD— This is used in certainrainproof compounds , one of which i s 16 parts of compoundedrubb er , 128 parts of paraffi n wax , 1 part of sugar of lead , 1part of alum in powder. The india rubber compound used contains no sulphur. Used also in artificial rubber and artificialivory. Specific gravity

LEAD N I TRATE .— A compound of lead and nitric acid con

taining per cent . of lead . I ts specific gravity is I t

crack l e s when heated , detonates when thrown on red hot charcoal , and takes fire when ground with sulphur. I ts color i swhi te and it i s largely used in dyeing and for making chromeyellow (which see ) . I t i s used with gums in the productionof shower-proof mixtures with sugar of lead and alum .

LIQUOR OF F LI NT.—See Sodium S ilicate .

M I M o-TAN N I C A CID.—See Catechu.

MURIATE O F A MMO N I A . -See Ammonium Chloride .MURIATI C A CID.

—See Hydrochlori c A cid .N I TRI C A CID.

-A strongly acid liquid consisting o f anaqueous soluti on of the pure acid . I ts action i s strongly oxidiz ing . T in and powdered antimony are rapidly convertedinto thei r oxides

,while turpentine , i f poured into the strong

acid,i s attacked with almost explosive violence with the evolu

tion of light and heat. Straw or sawdust may become ignited i fimpregnated with thi s acid . Cotton wool i s converted by itinto gun cotton . Rubber immersed in ni tric acid at a tem

204 A CIDS A ND A LKA LI ES

P OTASS I UM A CID TARTRATE OR CREAM O F TARTAR .

—A whitecry stal line substance with an acid taste , a very common ing red ient i n baking powders ; a l so cal led potas sium bitartrate .Specific gravity I t is made from purified tartar, or argol .I t i s us ed in art ificial ivory made from res ins in solution .

P O TASS IUM A RSE NATE .-A very solub l e compound of arse

nic with potash forming what is known as F owler’s solution .I n the dry state i t i s a wh ite powder soluble in a lcohol up to4 per cent . P otas s ium ars enate was used by F orster, i n hi searli est experiments

,to vulcanize part ial ly a compound made

up of india rubber and she l lac .P OTASS I UM B I CHROMATE .

—The principal compound ofchrom ium , which occurs in the form of orange- red crystal s ,spec ific grav i ty I t i s solub l e in water and i s largelyused in dyeing. M ixed with sulphuri c acid

,i t i s used in

b leaching palm oi l and other fats . B ichromate of potass iumis

,us ed in hardening the compound known as elasti c glue ;a l so used in Chri stia gum s .

P OTASS IUM B I SULPHATE .— A white powder O b tained as a

by-product in chemical manufacturing. Soluble in twice it sweight in co ld water

,and in half of it s weight of boi l ing

water . I t contains sulphuric acid so loosely he ld in comb ination that i t i s driven O ff upon heating. I ts Specific gravityi s

P OTASS I UM CARBO NATE OR P OTASH .— This substance is

us ually met with commercia l ly in small , colorless crystals . I t

i s prepared in a variety of way s'

and forms , and i s the bas i sfrom which is derived what i s cal led caustic potash . P earlash i s a crude form of potash mixed with the caustic vari etyand a sulphuret of potass ium . Used in certain proofing compounds where low heat i s required for cure . I t was used byCharle s Hancock

,m ixed with water in a bath

,to improve the

qual ity of gutta-percha . He found,by boi ling the guttapercha in such a bath for an hour, that i t did not oxidize in

the open ai r as badly . A n O ld - fashioned proces s for treatingunvul canized thread was to steep it in a hot solut ion of carb onate of potash

,wh ich greatly increas ed it s strength . See

Causti c P otash .

P O TA SS IUM CYA N IDE— QUI CKLIME 205

P OTASS I UM CYAN IDE .-A white crystal l ine subs tance

,very

poi sonous . Specific grav ity I t i s very easi ly decom o

posed,even on exposure to the air, absorbing carbonic acid

and y ie lding prus s ic acid , which gives the sal t it s pecul iarsmel l of peach kernel s . The vapors thus given O ff are verypoi sonous . Cyanide of potas sium was used by B rooman “togive clearness to the gum wh ich was made from the groundvulcanized rubb er, which had b een treated with alkal i es andacids to remove sulphur and adul terants .”

P OTASS I UM HYDROX IDE’

OR CAUSTI C P OTASH .— A s occurring

in commerce,this is a white sol id substance of the specific gravity

of about I t i s hard and b ri ttle , and very destructive toanimal and vegetab le substances . I t rapidly takes up waterfrom the ai r

,and may b e used to obtain a dry atmosphere in

a confined ves sel . I t i s al so a greedy absorbent of carbonicacid

,b ecom ing converted into the carb onate thereby . Solu

tions of potash Should b e c larified by a l lowing impuri ti es tosubside . A lcoholic caustic potash solution i s used in analysi sO f vulcanized india rubber and was introduced by Henrichs ,particularly to separate india rubber from india rubber sub stitute . Caus ti c potash i s mixed with flowers of sulphur forboi l ing drawing roll s , the potash making the rubber moresol id , while the sulphur gives a pecul iar surface , making itb etter for drawing . Used in water solution to remove bloomfrom cured rubber . I t i s al so us ed in 'certain sub sti tute s forhard rubber

,l ike voltit. Caustic potash was early us ed in

extracting the sulphur from ground vulcanized rubber .P OTASS I UM P ERMANGANATE occurs in dark red prismatic

crystals of greenish color which , when dissolved in water, givea purple red . It is a decided oxidizer, and is used as a d isinfectant. I t is also called chameleon mineral . Used in certain artific ial leathers . I ts specific gravity isQU I CKLI ME i s the impure oxide of calcium ob tained by

burning chalk , marble , or l imestone , or any carbonate O f calc ium . I ts well-known attraction for water renders i t unstablebut al so valuabl e where drying quali ties are desired . Specificgravity about B l i zzard claimed to be ab le to make aperfectly transparent rubber b y treating it with soda andwater, in which was a little quicklime .

206 A CIDS AND A LKALIES

RECLAI M I NG SALT.-A n alkal ine composition made in Ger

many and used ch iefly'

in the reclaiming of red and lightco lored rubb er waste .

REN N ET i s made from the inner lining of the true stomachof the suck ing calf and gets i t s value from the gastric juicecontained therein . The membrane , after treatment , i s saltedand stretched out to 'dry . I t i s advised in the Vaughn proces sfor coagulating balata .

SA L A MMO N IAC.— See Ammonium Chloride .

SA I.ERA TUs .— See Sodium Carbonate .

SALI CYLI C A CID i s ob tained from the creeping plant knownas W intergreen . I t i s prepared from the oi l of W intergreen(O il O f Gaul theria ) , wh i ch i s dist i l led in large quanti tie s inLuzerne county , P ennsylvania . I t i s al so prepared sy nthet

ically ; specific gravity I t i s soluble in the following proportions : 1 part of the acid dis solves in 450 parts of water, orof alcoho l . I t melts at 3 12 degrees to 3 14 degrees F . Sal icy l ic acid was used in an artificial leather compound for redueing leather dust to a paste , a fter which it was mixed with glueunder heat , and treated with an alkal ine solution.

SA L SODA .— See Sodium Carbonate .SALT .

—See Sodium Ch loride .SALTPETER i s n iter or potass ium nitrate . I t i s a white

crystalline substance having a saline taste , Specific gravityand is a very strong oxidizer. I t i s used in the manu

facture O f artificial elaterite . I n Gridley’s proces s for recovering rubber

,by exposing i t to flame

,saltpeter was added to

remove the smel l .S I LI CO N F LUORIDE i s a colorl es s gas . What i s us ed in thearts i s a soluti on in water , form ing a very acid fuming

l iquid . I t i s easi ly decomposed and may be us ed for etching glas s if al lowed to evaporate upon it under heat . I t

i s prepared from flints or s i l ica in some such form assand or powdered glass . Used in treating meerschaumand paper pulp wh ich ,

comb ined with certain resins , formsan artificial ivory .

SOAP . -Various kinds of soap are used in rubber manufacture . P ure Casti le soap , for ins tance , i s di ssolved in rain


be present in the fluid when finished . A higher strengthquick ly separates and sometimes causes the entire quantityto coagulate . M adagascar or S i erra Leone rubb ers are advisedfor borax solut ions . Solut ions of borated rubber are adaptedfor waterproofing and for preserving mats

,marine bedding

;

etc . B orax is al so advi sed for preserving rubber milk fromcoagulati on . I t i s al so an important ingredient in the watervarni shes used for luster fini sh

,for surface coats

,army

blankets,etc . ; i s used in waterproofing compounds composedof rubb er , boracic acid , kauri , tungstate O f ammonia ; mixed

with gutta-percha and shellac , i t was. used by Hancock as aninsul at ing material .SODI UM B I SULPH I TE .

—Used for bleaching plantation rub

ber during coagulation .SODI UM CARBO N ATE .

—A ISO called sal soda,washing soda .

P repared from cry olite , sa l t , etc . I ts specific gravity i swhen crysta ll iz ed . The crystal l in e form contains 64 per cent .of water O f cry sta l l ization , of which one-half i s driven O ff bygent le heating . I t i s found in the ashes of many plants , i sproduced artificial ly in large quanti ti es from common salt , andi s used as an alkal ine agent in many chemica l i ndustrie s .India rubber, burnt umber, j apan , and a coloring matter arem ixed with a certain proportion of sal soda for a waterproofing composition . Under the common name sa l eratus

,car

bonate of soda i s used as fol lows : I nstead of sunning surfacegoods , like rubb er coats and b lankets , they are O ften b rushedover with a m ixture of saleratus and powdered charcoal immediately after the stock leaves the calender. Sometimes thesaleratus i s left out and only charcoal i s used .

SODIUM CHLORIDE (or common salt ) has a specific gravityof It i s a very stable compound , soluble in water at theordinary temperature to the extent of 36 per cent . , and at theboiling point

,o f 39 per cent . A t the freezing point water will

take up 5% per cent . of common salt. I t i s used in coagulatingmany O f the rubber latexes . Salt i s viewed with considerabledistrust by ordinary manipulators of rubber. P ayne , however,treated gutta-percha scraps by boiling water, salt , and oil o f vitriol

,to get a solution to which he added other gums and metallicoxides to get a waterproofing mixture . Cooley made artificial

leather of gutta-percha dissolved in rosin oil , and added 25 per

S ODIUM HYDRO X IDE— S ODIUM P HOS P HA TE 209

cent . or more salt , to which he added starch or other sacchar ine substances . Sa lt solution is used in washing the compoundknown as tremenol . I t is also used in shower-proofing com

pounds , in connection with paraffin and sulphuric acid .SODIUM HYDROX IDE OR CAUSTI C SODA —Spec ific gravityThe chief use of this , in the manufacture o f rubber goods ,

is in the dissolving o f sulphur that is formed on the surface O fgoods

,and which i s known as bloom . A ccording to H . L . Terry ,

F the bulk of the alka l i supplied to rubber manufacturersin England is used in remov ing the sulphur from e lastic thread .I t is also used in treating tobacco pouches , fine sheetarticles

,and b lacks , reds , O r maroons , that should have a good

clear color. The boiling of rubbe r goods is usually done inwooden tanks in wh ich steam can be passed , and sometimes inslate tanks

,as iron is attacked by the alka l i . O n good grades of

rubber, caustic soda has no action at all . Where a large quantityO f resin is present , however, it may dissolve a part of it , forming resinate of soda . Heavily compounded rubbers , whetherthey conta in substitutes , gums , or compounds , unless they areabsolutely inert , are also l iable to be attacked through the dissolution o f their ingredients . Cami lle describes a process whereby shoddy i s treated with a solution of carbonate of soda in devulcanization . In this , the rubber is boiled several hours in a solution of caustic soda

,the result being that it wi l l sheet when the

process is completed . Rostaing purified gutta-percha by boilingin caustif soda , or in a mixture of caustic soda and potash inwater.

The largest use for caustic soda in the rubber industry isfound in the reclaiming of waste rubber by the alkal i processes .

“

SODIUM HYPO SULPH ITE .—A one per cent . solution is used

for remov ing traces o f chlorine where its presence is suspected inindia rubber.

SODI UM P HO SPHATE — A crystalline colorless substance containing 60 per cent . o f water

,which is given up on heating to

248 degrees F . , leaving behind a dry mass . The commercialarticle frequently contains sulphate of soda as an impurity . Thecrystals have a specific gravity of melt at 95 degrees F . ,

and are readily soluble in water. B y long drying at 113 degreesF .

, the water of crystallization may be entirely driven.O ff . The

210 A CIDS A ND A LKALI ES

presence of thi s material is called for in a certain compound fordental vulcanite , where it is incorporated with rubber, sulphur,and phosphate of lime

, the idea being that less sulphur is requiredfor vulcanization than in the ordinary compounds .

SODI UM S I LI CATE — See So luble Glas s .SODI UM SULPHATE occurs commercially in colorless crystals

which deteriorate in contact with the air, and hence should bekept in well-closed vessels . It contains a very large amountnearly 60 per cent— of water of crystallization , which is yieldedon heating to 302 degrees F . I ts reaction is alkaline . Sulphateo f soda was used by Hancock in vulcanizing gutta-p ercha . I ts

specific grav ity isSODI UM TUNGSTATE .

—P repared commercially f rom wolframore and soda ash ; usually contains about 14 per cent . water o fcrystallization ; and i s in the form of colorless crystals . M ixedwith a solvent such as methylated ether, it i s added to solublegun cotton , castor O il , and gum copal , forming a substitute forindia rubber. Specific gravity

SOLUBLE GLASS (known also as waterglass ) i s a silicate ofsoda or potash . I t i s usually sold in solutions of varying density,the commonest being 33 degrees and 66 degrees , by which ismeant that the solution contains either one-third or two- thirdssol id waterglass . A cids readily precipitate the S il ica from thesesolutions as a gelatinous mass . It is used in certain shower-proofcompounds and in compounds o f the algin type .

SULPHURI C A CID (called also O il of vitriol ) , when pure , isa colorless,heavy, oily liquid . I t is very corrosive , and has a

great attraction for water ; hence wood and other organic bodiesare charred in the heat evolved by it depriving them of theirwater . The specific gravity of the commercial acid is usuallyabout or 66 degrees B eaume, containing 94 per cent . of

acid . Sulphur i c acid is used in the coagulation of M adagascarrubber. The O rinoco CO .

,in Venezuela , are also said to have

coagulated india rubber by mixing the milk of the Hevea withsulphuric and carbolic acid . Commercial sulphuric acid is saidto coagulate 55 times its volume of gum, while the carbolic acidacts as an antiseptic in the juice , improving its keeping qualities .I t i s a question whether rubber treated this way is as good as .that obtained by the smok ing process . Rubber immersed in sul

2 12 A CIDS AND A LKA LI ES

TUN GSTI C A CID is derived chiefly f rom wol f ram, wh ich i s atungstate of iron and manganese . Tungstic acid is analogous tosulphuric and chrom ic acid . I t has been used in connection withparaffin

,gelatine

,and metallic oxides in proofing compounds .

ZI N C CHLORIDE was known formerly as butter o f zinc . I t

i s formed by burning zinc in chlorine gas , or by dissolving it inhydroch loric acid , the solution being evaporated . I ts specificgravity is The anhydrous form is a wh itish-gray masswhich readi ly fuses

,and can be sublimed at a h igh temperature .

I t deliquesces on exposure to the air, and is readily soluble inwater

,acting in a concentrated state as a powerful caustic . O ne

of the be st processes ever known for reducing the fiber inrecovering rubber was that in which this substance was employedinstead of acid . A boiling solution O f ch loride of zinc was used

,

in deodoriz ing-

by B rockedon, who also mixed it with guttapercha

,adding sulphur and vulcaniz ing the gum. Hancock also

subj ected gutta-percha for a moment or two to binoxide of nitrogen , then immersing it in a boi l ing solution of chloride of zinc ,which he claimed greatly improved its quality.

ZI N C I ODIDE .

— A very unstab le substance . A white granularpowder, odorless . Chiefly used in medicine . I t was used byHancock to assist in the vulcanization of india rubber. Specificgravity

CHA P TER X II .

VEGETA BLE ,M INERA L,

A ND A N IMA L O ILS USED IN

RUB B ER CO M P OUNDS A ND SO LUTIO NS .

TH E use of O ils in rubber manufacture has kept pace fullywith the use of gums , substitutes , and reclaimed rubber. The

addition of earthy or meta l l ic or vegetable ingredients in drymixing has rendered many a good rubber somewhat intractablea fault wh ich the right O il has often rectified . A s a rule , vegetableoi ls are '

chosen ,as they are rare ly harmful to the gum . Many

mineral oils are also free ly incorporated in certain compounds .A nimal O il s have always been viewed with more or less suspic ion,however

,and with good reason , for‘ manufacturers have

constantly before them rubber goods that have lost their l i fe andelasticity through contact with lubricants made of such oils andfats . N evertheless certain of them may be and are used . The

essential or volati le oils 'are used to a certain extent in rubber

manufacture . These O ils , as a rule , give the peculiar Odors o fplants from which they are derived . Their use in rubber is toimpart to it a pleasing Odor.

A LUM I NUM LA N OLA TE .— This is a product precipitated from

F rench wool grease , made by adding a solution of alum . I t i sdissolved in mineral O il , form ing a j elly- like mass wh ich is saidto compound readily with either india rubber or gutta-percha ,and is soluble in any O f their solvents . I t i s possible that thismay have both softening and preservative influences on indiarubber, as is c laimed , but it should be used with considerablecaution .

B LOWN O I LS — These are prepared by heating fixed vegetable O i l s in a j acketed kettle and blowing a current of airthrough the fluid . Under this treatment

,oils become much more

dense , viscous , or even sol id by comb ining with oxygen . In

many phy s ical aspects they resemb l e castor O i l,but diff er in

that they can be mixed with mineral oils and as a rule are notQ

2 14 O ILS IN RUB B ER COM P OUNDSeasi ly soluble in alcohol . B lown oils made from linseed oil

,rape

O il , poppyseed oil , and cottonseed oil are sometimes used in themanufacture of rubber substitutes instead O f the raw oils .Known also as thickened O ils , base oils , soluble castor oil , etc .CAMPHOR O I L — A l iquid of a light reddish-brown with a

ye l lowish tint, and a strong camphor O dor. I ts specific gravity isThe Japanese oil varies in color from colorless through pale

straw and yellow, to black , and has a Specific gravity of forthe colorless to for the very dark . This oil is used in the manufacture o f celluloid var nishes , paints , lampblacks , etc . I t i s usedalso as an adulterant for such O ils as sassa fras oil . I t i s one ofthe best so lvents for resins , and dissolves 46 per cent . of rosin , 9per cent . Copal , and 35 per cent . of mastic .CAOUTCHOUC O I L — Made by digesting 55 parts of india

rubber in 450 parts O f l inseed oi l . The principal large use forthis oil is in Germany, particularly in the army, for coatingvarious articles to prevent their rusting. The following sub

stances are found in oi l of caoutchouc : eupoine ,butylene ,

caoutchouc ine , i soprene , caoutch ine , and heveene .

CASTOR O I L— A colorless or pale greenish transparent O il ,very viscous and thickening on exposure to the air. I t has a higherspecific gravity than any other known natural fatty oil I t

is adulterated frequently with resin O il and rape , linseed , andcottonseed oils , especially the blown” variety . Used in cheapproofing s without rubber with kauri gum ; also in collodion andrubber proofing. I t is used in the production of substitutes likegum fibrine , and also with ch loride o f sulphur in producingamber—colored and wh ite substitutes .CHOLE STERI N .

-See Lanichol .

COD O I L OR COD-LIVER O I L is Obtained from the livers ofcodfish . N ewfoundland and Norway are the princ ipal manufacturing points . The finest is a very pale , clear, golden yellow, thecolor deepening to a brown in the second and third grades . I ts

specific gravity is to O ne part of oil i s soluble infrom 40 to 20 parts cold alcohol , or 30 to 17 parts hot alcohol .The lower grades are the more soluble . I t i s much adulterated .I s compounded with india rubber, beeswax , l inseed O il , litharge ,and asphalt as a waterproofing for leather and with india rubber, beeswax , and turpentine as a dressing for hides .

2 16 O ILS IN RUB B ER COM P OUNDSc ific gravity is about I t has great solvent power on allresins and gums

,including india rubber and gutta- percha . With

the addition of a l ittle methylated spirit it will dissolve evenkauri gum, cold . I t i s a l so used in dissolving asphalt for photograph varnish .

F I SH O I L.-O btained from a l l parts o f the bodies of com

mon fish by boiling. F i sh whose livers yield oil commerciallydo not give fish O il , and those bodies that yield oil , do not givel iver O i ls . P rincipally prepared from menhaden . I ts specificgravity varies between .915 and .930. F ish oil is used in themanufacture of the substitute known as volenite . I t i s used ,however, only as a vehicle for carrying resin into the fiber

,being

afterwards wholly removed .F REN CH WOO L GREASE — See Lanol ine .GLYCERI N E .

—A clear , viscous liquid without odor . Whenpure it has a specific gravity o f The glycerine of commercei s a by -product of soap manufacture . When fat (glycerinestearate ) i s heated with caustic alkali and water the alkali disengages and takes the p lace of the glycerine in the combination .

forming soap or stearate of the alkali,which separates out as a

solid , leaving the glycerine free in watery solution , from whichit i s recoverable . Glycerine is not acted upon by oxygen , andthere fore more c losely resembles mineral oils (such as are usedin rubber mixing) than it does the drying O ils that go to make upsubstitutes . I t has absolutely no solvent action on rubber .

A recent German patent calls for the addition of glycerinebecause of its O il- resisting qualities . In the compound used are 6pounds of rubber, and , 1 pound of glycerine , together with whiting

,l itharge

,and sulphur . A solution of glycerine and

alkaline fluid i s also used as a c leaning and polishing medium inthe last stages of the manufacture of certain cut- sheet goods .Glycerine , combined with gelatine and borax , has been used as awash for both black and red rubber surfaces .

Glycerine was the basis of a well-known deodorizing composition for india rubber

,the other ingredients being of an alki

l ine nature . A bath of glycerine has also been used for experimental work in vulcanizing india rubber, and also for rubberstamp making. In th is kind of work , the mold and its contentsare immersed in the glycerine SO that the l iquid just covers the

KERO SENE —JA P A N WA X 217

top of the mold ; heat is then applied to the glycerine , and themo ld in turn becomes hot and the rubber vulcanizes . I t i s alsoused to a certain extent in good grades of wh ite rubber, as itgives a softened eff ect to the compound . Glycerine , in connectiOn with glue , gelatine , mo lasses , and tann in , is used in themanufacture of puncture fluids for tires . I t is also used inclothing compounds , and in cellulose products , like pegamoid .Used in rubber, a little o f it increases the resiliency of the product .

H YDROLE N E .—A rubber assistant used in connection with

the reclaiming of rubber, and also rubber compounding. I t wouldseem to be a petroleum product, and in rubber reclaiming is usedinstead o f stock oil or residuum .

KERO SEN E .—A n il luminating oil of the paraffin series of

hydroc arbons . I ts specific gravity varies from to I t

has a flashing point (open cup test ) from 90 to 110 degrees F . ,

and includes all the intermediate distillates from crude petroleumof specific gravity to I ts color should be waterwh ite . In rubber work it is use ful to impart and retain softness in stocks in which it i s desirable to retain resil iency, as incertain solid playing balls . A lso it is very freely used in themanipulation of high-grade compositions used in hard rubbermanufacture . Calender rolls , mi ll rolls and zinc surfaces arekept coated with a film of kerosene to give the hard rubber composition a perfect surface, exclude ai r and lubricate the moldsand dies . Its use for the purpose of eff ectually suppressing theloss and nui sance occasioned by floating lampb lack in rubberm ixing

,has b een patented recent l y . The color i s ag g lomer

ated by damping and m ixing with kerosene b efore addition tothe g eneral batch .

JAPAN WA X .—A white or pale-yellow veg etable fat , with aspecific gravity of to I t is used in wax matches ,

candles , and for adulterating beeswax . A Special use for it , thathas arisen within the last few years , i s in the manufacture ofcravenette cloths . Most of this vegetable wax i s derived fromthe fruit kernels of a tree peculiar to Japan , which begins tofruit at about 15 years

,and sometimes bears heavily when it is

over 100 years old . I t reaches a height o f 20 to 25 feet,and

produces from 30 to 150 pounds of nuts annually. The best wax

2 18 O ILS IN RUB B ER COM P OUNDSi s made from nuts that have been kept over the winter

,and gen

erally speaking, the quality of the product improves with the ageof the nut The wax is extracted by crushing and steaming thenuts, and then subj ecting the mass to pressure . A second wax issecured by repressing . O ne workman can handle about 150pounds O f raw mass in a day , and this produces about 16 poundsof wax .

The crude wax is cast into round molds of a little more thana pound each . I t is next refined

, the process used being a traditional one and pecul iar to Japan . I t

_is mixed with wood orcharcoal , ash and water, thorough ly bo iled , and dropped intocold water, so as to form what are called wax flowers . Theseare taken out and exposed to the sun for about 20 days , whenthe process o f boiling, mak ing the flowers , and sunning isrepeated . The wax is then boi led a third time , and the best quality taken off the top while it is in a molten condition . Recentlyimproved methods have begun to come into use

,and the crude

wax is treated with an alkaline solution .LALLEMANTI A O I L i s Obtained from the seeds of the Lalle

mantia ibcr ica,a plant cultivated in Russia . This is one of the

best d rying oi l s , being said to surpass even linseed O il , but itschie f use is for illuminating purposes . In Europe it i s said tohave been used instead of linseed O il in rubber substitutes .

LA N I CH OL.

—A product of lanolin (which see ) , made fromthe O il of sheep’s wool . I t combines with gutta—percha and indiarubber in any proportion to a perfectly homogeneous mass . Thisgrease does not oxidize and is wholly antiseptic . I t has no smell ,and is impervious to the action of alkalies or to dilute sulphuricacid . I t is said that , used in connection with gutta—percha , themelting point i s considerably raised , while it does not diminishthe insulating property. A n insulating compound given i s 50parts by weight of gutta-percha , 30 parts of india rubber, 20parts lanichol . The inventor claims that it renders gutta-perchaless liable to oxidation , improves its elasticity and tenacity , anddiminishes its liabil ity to become sticky. P atented in the UnitedS tates and Great B ritain by Robert Hutchinson .

LAN OLI N i s also known as wool grease , recovered grease ,and brown grease . I t i s the natural grease found in sheep’s wooland recovered from it while the raw wool is being prepared for

220 O ILS IN RUB B ER COM P OUNDSreason that the B lack sea seed contains a certain amount of hempseed

,whi le that from India i s usual ly mixed with rape

,cameline ,

and mustard seeds . The oil wh ich i s expressed from these seedsis of a golden ye l low co lor, with a pecul iar taste and odor . Spe

cific gravity Linseed oil becomes easily rancid in theOpen ai r

,but when spread in thin films dries into an insoluble

substance wh ich has been called l inoxyn . Linseed oil i s adulterated sometimes by fish or mineral oil s , and by resin oils . O ld

tanked linseed O il i s used in the preparation of what is knownas boi led oil ; that i s , it i s concentrated by heat at a high temperature that it may more rapidly dry when used in varnish .

This drying process is hastened by the addition of manganesedioxide , litharge , etc . B oiled linseed oi l i s much darker than rawoil , hav ing a brown- red shade . I t i s also much more viscous andhas a higher specific grav ity . B oi led O il i s adulterated in thesame manner as is raw l inseed oil

,the adulterants being resin

oils,resin

,and mineral O ils .

In rubber compounding linseed O il i s very O ften used . A

very simple formula for waterproofing canvas is india rubber ,l itharge , sulphur, and linseed oil . I t i s also used in rubber varnishes

,to a certain extent in molded goods

,and quite largely in

hard rubber compounding. I t is the basi s of a great many ofthe sulphurized or vulcanized oil substitutes . Linseed O il thati s intended for mixing in l inoleum is exposed to the air until iti s thoroughly oxidized . In this state it i s insoluble in alcohol ,chloroform , ether, and ordinary solvents .

LI THOGRAPH I C VARN I SH is obtained by boiling linseed O il ata temperature higher than that at which boiled oil is prepared ,nor are dryers added during the boiling. It i s a perfectly clear,transparent substance , the best quality being nearly as light asraw linseed oil . There are two ordinary grades of lithographicvarni sh . O ne i s known as “burnt O il

,which is obtained by

bringing raw linseed oil up to its flash point , and allowing it toburn until the requi red thickness is reached , it'

being constantlysti rred meanwhi le . “O xygenated O il

” i s a linseed O il varnishmade by treating the O il with oxygen in j acketed kettles

,heated

by steam . The product is as light colored as raw linseed oil,

but heavier. I t i s also more readily soluble in alcohol , and hasmarked drying powers .

MUSTA RD O IL— OLI VE O I L 221

M A NGA N A TED LI N SEED O I L is used in certain rubber compounds where more of a drying eff ect is needed than is found inthe raw l inseed oil . I t is l inseed oi l that has been boiled withperoxide o f manganese to increase its dry ing qualities . See

B oiled O il .M I RBAN E O I L .

—See N itrobenzene .

MUSTARD O I L — B lack mustard O il i s Obtained f rom theseeds of the S iuapis nig ra . It possesses a mild taste

,is of a

brownish-yellow color,and in its chemical composition closelyresembles rapeseed oil . I t i s a by -product and is largely used in

soap mak ing. I ts specific gravity varies f rom toWhite mustard oi l is made from the seeds of the S inapis alba .

I t is ye l low in color, and almost identical with black mustardoil . Used in making rubber substitutes .

NEA TSF OOT O I L .

—A pale-yellow or colorless oil,obtained

from the feet of oxen by boiling in water . I t has a smooth ,pleasant taste . O n standing it deposits stearine . I t i s largelyadulterated with cheaper animal or vegetable and even mineraloils . Neats foot oil , mixed with gutta-percha , tallow , sweet O il,and oi l of thyme , is used as a rust preventive . I t i s used inconnection with beeswax

,india rubber , and B urgundy pitch in

a composition for dressing leathers or hides . I ts specific gravity is to

N I TROBEN ZEN E OR N I TROBEN ZOL (also called O il O f mirbaneand “ imitation O il of b itter almonds” ) i s a yellow aromatic , oilyl iquid o f specific gravity produced by the action of nitricacid on benzene . I t i s used in perfumery and turned out ingreat quantities for the manufacture of anil ines . I t i s used alsoin certain insulating compounds in connection with asbestos

,

powdered glass , vulcanized rubber , castor O il , resin O il , andcel luloid in solution .

O LEA RGUM .—A black vi scid l iquid leather dress ing of an

0 i nature used as a dul l finish wash for rubb er boots . I ts

compos ition i s a trade secret .O LIVE O I L is expressed from the f ruit o f the O l ive tree , prin

c ipally in the countries of Europe bordering on the Med iterra

nean . I ts specific gravity is I t is adulterated frequentlywith cottonseed oil . O l ive oil is used in taking impressions f rom

222 O ILS IN RUB B ER COM P OUNDStype faces in the matrix in wh ich rubber type i s cured . Mayallsuggested the mixing of O l ive oil with clay until it formed a softputty, and then incorporating it with india rubber, the proportion being pound o f oil to 30 pounds of

, gum. The use O f theoil enabled the goods to be more largely adulterated ; he also usedolive oil in connection with devulcanized rubber

,not as a sol

vent, but because he claimed that it combined with the gum andimproved its quality . O live oil i s also used in hard rubber compounding. Rubber is sometimes heated up in olive oil mixedwith zinc , soap, and borax for a proofing solution . I t i s also usedin the manufacture of pegamoid .

O RRI S O I L is prepared from orris root . I t has the consistency of butter, melts at 100 degrees F and is miscible withalcohol . I ts odor is like that of violets . I S used in rubber as adeodorizer. Specific gravity

P ALM O I L i s Obtained from the f ruit o f various species ofpalm , principally from the west coast of A frica , and is known incommerce under as many names as there are ports of shipment .It i s expressed in a very rough fashion by the natives , who stirthe palm kernels in holes in the ground '

until fermentation sets inand the O il rises to the surface . They also sometimes press theO il f rom the fresh f ruits . The harder grades o f palm oil areyielded by the former process

,the latter giving the finer oils .

P alm oil varies in consistency. I ts specific gravity is itscolor yellow to reddish ; its Odor that of violets . I t yields a soapreadily with alkalies and dissolves in ether and in alcohol ofspecific gravity. P alm oil is very rarely adulterated , unless it isdone by the native gatherers , who sometimes add sand as a makeweight. Commercially, where sand and water together exceed 2per cent . , an allowance i s claimed from the seller.White palm oil is that -which has been bleached by heat ,chemicals or exposure to the air. “

Lagos oil” has about the sameconsistency as butter, while “Congo oil” i s as thick as tallow .

P alm oil i s used largely in the manufacture of mechanical anddry-heat goods

,chiefly to enable dry ingredients to mix more

easily with .india rubber. I t has also been used in the recoveryO f waste rubber by mixing it with the finely ground rubber andexposing the mass to a heat o f 572 degrees F . P alm oil residuum

224 O ILS IN RUB B ER COM P OUNDSuct

,dark greenish

,translucent , slightly fluorescent , sem i- solid ,

melting at about 100 degrees F . , and having a specific gravity ofI ts chemically inert quality pecul iarly adapts petrolatum

to use in rubber compounding where a non- oxidizing lubricantand softener is needed to faci l itate manipulation of harsh or drycompounds , and not subsequently deve lop in the finished goodsinjurious or other undesirable qualities . A ny oil will softenrubber, but for all around adaptability petrolatum excels allothers .

O rdinarily 2 or per cent . of petrolatum is sufficient inany compound where its presence is needed , although 5 or even7 per cent . may be employed in special cases . Cheap goods containing petrolatum will withstand drying out or hardening withage

,a similar eff ect being produced by the use of soft coal tar.

A s regards the item of economy , P etrolatum commends itsel fto the rubber manufacturer when considering the use of an oilingredient in compounding. F or a l l ordinary purposes , everything except perhaps the whitest goods , the dark filtered stockis enti rely suitable and the price wi l l be less than the light filteredstock .

P ETROLEUM JE LLY .—See Vaseline .

P ETROLEUM O I L (also known as Rock O il ) i s a dark , illsmelling l iquid , obtained from wells sunk in oi l -bearing sands .Some Russian O ils , however , are colorless . White Rangoon O ilcontains so much paraffin as to have the consistency of butter.The specific gravity O f Ameri can petroleum varies from toorP O PPYSEED O I L is obtained by pressing the seeds of the com

mon poppy (P apaver somniferum ) . Commercially there are twogrades , white and red . Th is oil has no O dor ; it is rarely adulterated with other oils , although occasionally sesame oil is foundin it ; it i s an excellent drying oil , and its lower grades are usedin the manufacture of soaps ; its use in the rubber indust ry ischiefly in the manufacture of substitutes . I ts specific gravityvari es from to

RA PE SEED O I L OR COLZA O I L i s pale yellow in color,with

an unpleasant , hard taste . I ts specific gravity is aboutI t i s largely adulterated with vegetable , mineral , or fish oils . I t i s

ROS IN O IL— TALLOW 225

obtained from the seeds o f the B rass ica campestris , and of several varieties of this genus which are cultivated . American ”oilsf rom all o f these are t ermed colza or rape oil indiscriminately.In Europe , however, rape is one kind of oil and colza is another .There are also what are called the summer O il and the winterO il, a distinction which is O f no interest to rubber manufacturers . Rape O il i s about hal f way between a semi-drying O il

and a non-drying oil . It is used in the manufacture o f rubbersubstitutes . M ixed with india rubber it has been used as asomewhat costly mixture for lubricating mach inefy .

ROSEMARY O I L— A n essential oil o f the specific gravityColorless and having the odor of rosemary. Used with

india rubber, paraffin , and spermaceti in waterproofing compounds, and , where rubber is present , to neutralize its odor.

ROS I N O I L— Made by subj ecting rosin to destructive distillation . Specific gravity The resultant O il i s heavierthan mineral oils , and its chemical composition is quite involved .I t i s largely made up of hydrocarbons , with a certain amount ofresin acids . Used in making a waterproof solution , by the addition of Japan wax and gum thus , in the manufacture of a solution for treating hides and leather. Used also in compounds forcalking ships in which india rubber has a part , and is an important ingredient in the manufacture of guttal ine . See Ros in .

RUSS I AN M I N ERAL O I L— P etroleum from the B aku oil wells .SHALE O I L.

— Chiefly produced in Scotland from a dark ,coal- l ike shale . I t is s imilar in nearly all respects to petroleumoil . Used with asphaltum in certain insulating compounds .STEARI NE—A n important ingredient in animal and vegetablefats . I t i s quite sol id , and increases the hardness and raises

the melting point o f fat . Commercially, stearine is also known asstearic acid and consolidated oil . I t i s an important element inthe manufacture o f cravenettes , where it is used with ozocerite ,beeswax

, paraffin, and Japan wax . Specific gravityTALLOW.

—B eef tallow, when fresh , i s almost white, freef rom disagreeable Odor, and almost tasteless . O n the other hand ,foreign tallow runs from white to yellow and is often quite rancid . Tallow is o ften adulterated with rosin O il , coconut oil , cottonseed O il, and paraffi n wax . I t i s used in non-drying cements

226 O ILS IN RUB B ER COM P OUNDSin connection with slaked lime and india rubber. In connectionwith india rubber it is also used in the production of what wasknown as Derry’s waterproof harness oil , which was made ofindia rubber

,tallow, seal oil, and ivory black. A n etching var

nish is made of gutta-percha , turpentine , beeswax and tallow .

A small amount of this was used by Hancock in compoundingfor softening gutta-percha . It is used with gutta-percha in shoemakers’wax , and also in certain proofing compounds with indiarubber, pitch and linseed oil . A mixture of india rubber, beeswax, l inseed O il and tallow makes an excellent dressing forleather.

TA R O I L—A h O il distilled from tar. It i s a mixture ofseveral lighter O ils , and i s made up of liquid hydrocarbons whichhold in solution small quantities of anthracine, naphthalin andparaffin . I t has been recommended as a coating for rubber, itbeing claimed that it has a preservative eff ect. I t i s also usedin compounds for surface clothing.

THYME O I L (also called origanum oil ) i s extracted fromthe flowers and leaves of the Thymus vulgaris . I t is yellowishred in color ; its specific gravity is and it has a pungenttaste . It i s used to disgui se the odor of ale cements .

TURPENTI N E .— See Spi rits o f Turpentine .

VASELI N E i s the purified res idue from the di sti l lation ofpetroleum . Its specific gravity is .875 to .945. I t i s insoluble inwater , barely soluble in cold , but soluble in boil ing absolute alcohol , and in ether, bisulphide of carbon, oil of turpentine, benzine,and benzol . I t i s the basi s of a cheap waterproofing process, theother ingredients being sil icate o f soda , alum and hot water.Vaseline i s used quit e often in general compounding for it ssoftening eff ects . I t i s al so combined with menthol and gumol ibanum in the manufacture of porous pla sters . Vase line hasbeen used in the manufacture of substitutes similar to Rubberite .

See P etrolatum .

VULCAN I ZED O I L—These are solid dry sulphurized vegetable oils,commonly known as rubber substitutes .

WALNUT O I L.—C01(1 drawn oil i s very fluid , almost color

less,and of an agreeable nutty flavor. I ts specific gravity i sHot pressed oil has a greenish tint and an acrid taste and

CHAP TER X III .SOLVENTS USED IN COMMERCI A L A ND

P RO O F ING CEMENTS .

TH E beginnings of the manufacture o f india rubber consisted in operations with the gum in s olution and it was a considerable time before the discovery of the present processes ofdry mixing, which are employed in the production of the greaterpart of the rubber goods now made. There are certain lines ,however, where the use of solvents is still both necessary andeconomical . In the mackintosh manufacture

,for example , therubber is in almost every instance spread in the form of solution , as a thinner coat can be spread in this way, offsetting thecost o f the solvent . Many sheetings in various colors that only

a few years ago were calendered , are now coated by the meansof solution . In the making up of almost all lines of rubbergoods, cements are necessary, and these are ordinarily made inthe factory that produces the goods . The cements that are soldin bulk, such as channeling cements , for leather shoe manufacturing, as well as cements that are sold in smaller packages torepair men in the cycle industry, all consist O f rubber and analogous gum treated with some suitable solvent. Rubber being ahydrocarbon is soluble in the usual hydrocarbon solvents . Theseare usually those not soluble in water and of an 0 i nature .

The following tables show the solubility of rubber. The

first, which is taken from the “Journal of the Society of Chemical Industry,” i s a table of the solubil ity of masticated caoutchouc .

Ceara Para S ierra Leone100 Parts of Rubber Negroheads Rubber

TurpentineCh loroformBenzine I i

f"

Carbon bisulphide None. None.

Hoff er gives, as a result of his individual experiments , thefollowing table of solubilities of well-dried india rubber228

S OLUB I LI TY O F RUB B ER RES INS 229

PercentageSolvents Dry Rubber

65 to 7048 to 52

O il of turpentine 50 to 52

Caoutchine 53 to 55

Ether 60 to 68

Camphene 53 to 58

The great diff erences in solubility between various grades ofrubber have been found to be due largely to the amounts o f resinsthat are contained in them. A s these resins are soluble, and insome cases can be removed , it is important that rubber manufacturers not only appreciate thei r presence, but, where it ispracticable, dissolve them out. These resins consist of abieticacid or S imilar body, according to Lascelles-Scott, who has tabulated their solubil ities as follows :

SOLUBI LI TY O F RUBBER RESI N S .

Normal Res in Normal Res in(soluble in Descr i tion of (soluble in

85 p . c . Alcohol) Ru ber 85p. c . Alcohol).91 Ceara.60 A ssam

A ssam 4 88Burma 5 20

.85 Rio 3 37A frica (various )A frica (various )A fr ica (various )Mang abeiraO r ig in unknownO r ig in unknownO r ig in unknown

In some of them oxygen is a component part, and they areall soluble in alcohol of 85 per cent. strength and upwards . It

will be noticed from this table that P ara rubber has the least percentage of resin , and , of course, i s the most valuable. The

samples containing the largest proportions of resin were unmistakably adulterated with other gums during collection .C. O . Weber gives the percentage of resm m a number ofsamples of rubber as follows

P er Cent.Resin Grade of Rubber

S ierra LeoneA ssamMangabe iraA fr ican bal l NO . 1 .

A fr ican bal l NO .

A fr ican flake

230 S OLVENTS F OR RUB B ER

Clayton Beadle and Henry P . Stevens in their investigationon the insoluble constituents o f Ceara and Rambong rubbersfound that the “insoluble” and soluble constituents are separated by allowing the rubber to swell in a large excess of benzene ,when on long standing the heavier insoluble portion collects inthe lower hal f of the solution , the rubber being recovered fromthe upper and lower halves , respectively, by spontaneous evaporation . The authors concluded that thei r analysis and physicaltests showed that the insoluble matter plays the part of a sulphurcarrier and vulcanizing agent , independent of the proportion ofthe nitrogenous substance it contains .

The patent o f F rankenberg (English ) covering the production of non- inflammable solutions of rubber is of exceedinginterest as suggesting the use of new and safe solvents . To—dayfew chlorhydrins are used , because of their expense , but a number of them are on the market and the cost i s steadily beingreduced . F rankenberg’s solutions are produced by mixing rub~

ber w ith carbon tetrachloride, dichlor-methane , trichlor-ethane ,tetrachlor-ethane , or trichlor-benzol , alone or together. The

rubber may be softened with coal-tar -naphtha or other solventbefore the above solvents are added .RUBBER SOLVENTS .

A CETON E is a colorless mobile liquid , with a very unpleasanttaste and pecul iar odor, and outwardly resembling alcohol . Specific gravity I t is a good solvent for many organic substances , and for many gums and resins . A cetone is produced bythe destructive distillation of acetate of lime, which is one O fthe ‘ chemicals made from the products o f wood distillation . I t

has a specific gravity of boiling point o f 134 degrees FI t i s a solvent for rubber resins , dissolving about 18 per cent . ofP ontianak resin while hot and is recommended as a solvent foruse in analysis o f rubber, as it is without action on the gum.

A LCOHOL,when pure , i s a colorless , thin , mobile l iquid , of a

somewhat disagreeable smell , and specific gravity A bso

lute alcohol is that which has been deprived of all water. I ts specific gravity is It eagerly absorbs water, and , as it becomes more dilute , its specific gravity ri ses ; alcohol O f 60 percent . has a specific gravity of There are a number of forms


white mass . I t i s also used in treating many of the pseudo-guttasto dissolve out the brittle resinous matter. I t has also beenclaimed that the washing of raw rubber with alcohol dissolvesresinous ingredients which are better absent , and that the rubber as a result lasts longer. Rectified spirit i s what is generallyused in connection with india rubber. I t is used by the gatherersto coagulate the latex of the balata , and is used also in the production O f resinolines (which see ) . O ne of the early uses wasto mix with it various solvents— for instance , with spi rits ofturpentine, coal oil , bisulphide of carbon , ether, chloroform ,

etc .When illsmelling solvents were used , it was also often incorporated to neutral iz e the odor. Dental and other gums areexposed to the sunlight in alcohol to increase the brill iancyof the colors and to make the Shades l ighter. A lcohol i salso used to soften vulcanized rubber when a surface color is tobe added . A lcohol , in connection with nitric acid , spirits of turpentine, and aniline, was used by Kelly for surface work onindia rubber.

A NTHRACEN E .— See Naphthalene .

BEN ZOL,B EN ZOLE OR BEN ZEN E i s a volatil e O il Obtained in

the distillation of coal tar, which must not be confused withpetroleum benzine or petroleum naphtha . Its specific gravityi s at 32 degrees F ., and at 68 degrees F . Chemicallyit consists of 6 parts carbon and 6 parts of hydrogen . I t is thebasis for the manufacture of aniline dyes and many other coaltar derivatives used in the arts . I t i s the basis of nitrobenzeneand aniline, the coal-tar colors . Commercially it is sold as pure,90 per cent. and 70 per cent . B y 90 per cent . benzol it is meantthat 90 per cent . wil l dis ti l over at the temperature of boi l ingwater and likewise with 70 per cent . The commercial benzol i sto a great extent obtained from the gas produced in the distillation of bituminous coal in the by -product coke oven . The commercial article is a mixture of benzol with higher boiling bodieswhich are very similar in their chemical properties , and thesebodies are mostly toluol or toluene , which boils at 232 degreesF . and xylol or xylene, which boils at 287 degrees F . and higherboiling homologues . I t i s slightly soluble in water, and f reelysoluble in alcohol and ether, and in bisulphide O f carbon . I t has

CAM P HENE— CAM P HOR 233

great solvent properties . B enzol is used largely as a solvent forrubber in manufacturing tire and inner tube cements .

B enzol is superior to carbon bisulphide as a solvent forchloride of sulphur and there fore i s much used in the cold vulcanization process for curing light coated fabrics and thin , purerubber goods . F or this purpose benzol has the advantage ofgreater cheapness both as to price per gallon and as to lesserloss in handling than carbon bisulphide. This refers more particularly to the high grades o f benzol , l ike 100 per cent. or C. P . ;

the 160 degrees benzol is mostly used where a solvent is requi redthat must not evaporate too rapidly. I t i s said that i f guttapercha is put in 20 times its weight O f boil ing benzol , to whichone- tenth of plaster is added , and the mixture agitated fromtime to time

,a perfectly clear solution may be decanted . This

i s then mixed with twice its volume of 90 per cent . alcohol andthe gutta-percha precipitated a pure white .CAMPHENE i s a name applied to one of the varieties o f spirits

of turpentine, which was once largely used as a burning fluid .I t is very volatile , and the vapor makes with the ai r an explosive .Specific gravity Camphene was formerly used to a certain extent as a solvent for india rubber. Under N ewton’smethod of recovering rubber, the waste was placed in a closedvessel , covered with camphene , and heated to 158 degrees F . forfourteen days . The solvent was then distilled off , and the toughmass remaining was capable of utilization , and was somewhatsimilar to unvulcanized rubber. I t was also used in boot—heelcements in the old—fashioned method of attaching them to rubberboots , and also in general shoe cements and in varnish for rubberfootwear . Camphene was likewise used in putting vulcanizedwaste, finely powdered , into a solution in connection with etherand alcohol , in a simple but somewhat expensive process ofrecovery.CAMPHOR has been used as a solvent for utilizing the waste

of vulcanized rubber and of hard rubber, the waste being firsttreated with any ordinary solvent and then placed in a still witha certain amount O f camphor

,when the india rubber is dissolved

and the solvent passed out and distilled over again . Granulatedcamphor, over which had been passed sulphurous acid gas until


it was reduced to a liquid , was used also as a solvent for indiarubber, by A lexander P arkes . Specific gravity

CA OUTCH OUCI N E , also spelled caoutchine, i s a crude oil ofindia rubber, made by its dry distillation , and smelling much likenaphtha . It is an excellent solvent for india rubber, but of courseis too expensive for ordinary use. India rubber immersed in itswells exceedingly

,and a considerable quantity of it i s dissolved

during the boiling. I t must be kept in hermetically sealed vessels

,as it has a great affinity for Oxygen

,which it absorbs ener

getically . In preparing it,the india rubber i s treated in a retort

at a heat exceeding 400 degrees F . Caoutchoucine dissolves inether or alcohol , and , absorbing oxygen freely, forms a resinousbody as a result . Specific gravityCARBON B I SULPH IDE .

— This excellent rubber solvent is achemical prepared by the direct combination of carbon and sulphur under the influence O f high heat . I t is a colorless l iquid ,the specific gravity of which is I ts great volatil ity at ordinary temperatures makes it a most rapid d ryer. When mixedwith air and heated to 150 degrees C . it will explode . I ts usualbad Odor is due to sulphureted hydrogen and the presence offoreign matters , from which it can be thoroughly freed by purification. I t i s highly inflammable . I t i s a good solvent and hasgreat affinity for sulphur, 100 parts dissolving 37 parts of sulphur cold , or parts at 100 degrees F . B isulphide of carbonmixes with every known substance capable o f vulcanizing rubber. I t also assimilates rapidly with all fatty O ils , and dissolvesall the resins , with the exception of shellac . I t does not dissolvevulcanized rubber, however. Where it is used in rubber factories care is taken , as a rule, to remove the fumes , as they areinjurious to the workmen . Some very serious cases o f chronicpoisoning have occurred through the use of this solvent , thesymptoms being numbness , partial paralysis , and , in some cases ,temporary insanity. The use of bisulphide of carbon in rubberfactories is very care fully watched , there fore , by the authoritiesin Europe

,proper means for ventilation and carrying off the

fumes being insisted upon , and minors being excluded fromrooms where it is used . I t is one o f the best and most commonsolvents for india rubber, very largely used in the P arkes coldcuring and S imilar processes , and in cements .


vo latil e parts , so that with a continued use O f benzine the remaining less valuable ingredients , the heavier oils , must finallybe enriched by important additions of fresh benzine or gasol ine .

A n apparatus installed for the recovery O f the solventsdoes not need to be remodeled for the recovery of carbon tetrachloride , and the distillation process may be l ikewise carriedthrough in the customary manner. Carbon tetrachloride doesnot in the least aff ect the colors of fabrics . The most del icatecolors , even aniline colors of silk, satin , laces , etc ., are notaffected in th e slightest degree . A mixture consisting of equalparts of turpentine and carbon tetrachloride cannot be ignitedat ordinary temperatures . A mixture o f 60 per cent . carbontetrachloride and 40 per cent. naphtha is likewise non- inflammable at ordinary temperatures .CHLORO F ORM is prepared generally by distilling together a

mixture of grain alcohol with bleaching powder and water. I ts

specific gravity is from to I t i s one of the best rubber solvents known . I t i s costly

,however, and it should be remem

bered that a small percentage of chloroform in the air, even aslittle as 5 per cent ., i s dangerous to the workmen . LascellesScott mentions what he calls the A . C . E . mixture , composed ofalcohol 15 parts, chloroform 38 parts , and ether 47 parts , whichyields a powerful solvent for india rubber or gutta-percha .Chloroform dissolves not only india rubber, but fats , resins , sulphur, alkaloids , and many other organic compounds . Chloroform is used as the solvent for india rubber which is treatedwith the ammonia gas process for bleaching. I t i s also usedalone , and in connection with naphtha for rubber cements , whichare intended to adhere to glass . In the bleaching of guttapercha

,it is also used as a solvent . O ne of the first uses of

chloroform in connection with india rubber i s to be noted underan American patent granted to Charles F . Durant .CHUTE’S RUBBER RES I N SOLVENT.

—This is a mixture ofmethyl acetate with either acetone or methyl acetone . P atentedin the United S tates in 1907.

DI CH LOR-ETHYLEN E i s a non- inflammable, non-poisonous solvent

,of German origin . I ts specific gravity i s with a

boi l ing point of 181 degrees F .

ETHER— I S O P RENE 237

DI PPEL’S O I L OR B ONE NAPHTHA .— A thick, viscid oil O fbrown color and very disagreeable odor, of specific gravityO n distillation it may be Obtained limpid and colorless . I t isprepared by the destructive distillation of bones , leaving boneblack as a residuum . I t i s chiefly used to make lampblack . I t

was one of the early solvents used for india rubber.ETHER .

— This was one of the early solvents used in connection with india rubber. I t i s sometimes erroneously called sulphuric ether. It i s prepared usually by distill ing a mixture ofalcohol and sulphuric acid , washing the disti llate , and recti fyingthe product with quicklime . It is a colorless , very mobile liquid ,with a not unpleasant smell and is very volatile . I ts specificgravity is It i s soluble in water 1 to 12 . Commercialether boils at 96 degrees F .

, and yields a dense vapor. It i s veryinflammable,and when mixed with air or Oxygen , gives rise to

a dangerous explosive mixture . It is one of the best solventsknown for oils and fats , and is also an excellent solvent forsulphur. F or use in rubber work ether should be f ree fromwater, but not absolutely pure, necessari ly. It is little usedto-day in rubber mill s , except in some lines of very fine work .I t has the advantage of being absolutely free from the Objectionable Odors that many solvents have . A l ittle is sometimesadded to naphtha to make a complete solution of india rubber.There are also certain processes , expensive ones to be sure , fortreating perished rubber with ether vapor to recover it: E therwas used to remove sulphur f rom vulcanized india rubber wastein Newton’s camphene process .

ETHYL CHLORIDE OR“DUTCH LIQUID has a specific gravity

ofGASOLI N E — See Naphtha .HEPTAN E .

— O ne of the four i someric hydrocarbons of theparaffi n series , which occurs as a colorless l iquid and i s derivedfrom heavy cannel coal O il, petroleum,

etc . I ts specific gravityis I t is soluble in alcohol and in ether, and is used withparafli n wax and india fubber in water- repellent compounds .

I SOPRENE .—A body found in oil o f caoutchouc .

.I t boils at

degrees F . , and possesses the property of absorbing quantities of oxygen when exposed to the air, in consequence of


which it forms an elastic, spongy mass . Specific gravityI soprene is obtained by the action of moderate heat on oil ofturpentine and is interesting as a basis for obtaining syntheticcaoutchouc by polymerization .

The presence of isoprene formed in a reaction of a diolefine with conjugated linkings i s detected by ,

Ivan O stromy slenskyby shaking 5 to 10 drops of the products of the reaction for ashort time with 50 cc . of concentrated aqueous sulphur dioxidesolution

,the mixture being then left at the ordinary tempera

ture in a hermetically sealed vessel . In the course of 2 to 30hours an abundant, colorless , amorphous precipitate is formed .This consists O f a compound of the diolefine with sulphur dioxide possessing characteristic properties .

I soprene may be determined quantitatively by converting itinto -d ichloroisopentane . I f 0 grams of the dichloroisopentanecompound be obtained f rom S grams of the crude isoprene , thelatter contains 3403 a X S per cent. isoprene . The procedure i s as follows : 200 grams of the crude isoprene , containing butylenes , amylenes , benzene , etc ., with boiling point 86to 104 degrees F . ,

i s energetically shaken with 1500 cc . of fuminghydrochloric acid for 6 hours in a mechanical shaker. The

black, Opaque upper layer of chloro-compounds is separated,washed w ith aqueous sod ium chloride solution saturated in thecold , again separated after the emulsion formed has separatedinto two layers , dried over calcium chloride and distilled . A t

104 to 122 degrees F . only two or three drops o f hydrocarbonsgenerally distil over, and the fraction 122 to 194 degrees F .

contains butylene and amylene chlori des . The f raction 194 to266 degrees F . i s collected separately. F rom 266 degrees F . thetemperature usually jumps immediately to 288 degrees F ., theboiling point o f the -dichloroiSOpentane . When the crudeisoprene has been obtained , for example , from turpentine , the

-dichloroisopentane cannot be distilled , but it is found that theresidue distilling with boiling point beyond 291 degrees F . consists , in spite of its black color, of almost chemically pured ichloroisopentane. This residue may be filtered through glasswool and the filtrate weighed . The f raction boiling at 194 to266 F . i s subj ected to careful f ractional distillation , as it contains -dichloroisopentane, sometimes in considerable quantity.


P etroleum naphtha is a general name embracing a series oflight distillates f rom crude petroleum. In the order of theirlightness of gravity and boiling points the petroleum naphthasare : rhigolene (specific gravity about gasoline (specificgravity benzine (specific gravity 0 680 and ligro'in .

The distinction should be noted between the petroleumdistillate benzine” and the coal- tar distillate “benzene or benzol .

Ligro'

in i s a naphtha similar to benz ine , used as a burningfluid in the ligroin or “Wonder” lamp .

These products evaporate rapidly in a current of warm airand form explosive mixtures with the air.Coal-tar naphtha was one of the first solvents used in rub

ber work . Macintosh , as far back as 1823 , prepared it himsel ffor dissolving india rubber for proofing. There is obtainedfrom crude coal-tar naphtha what is known as “once- run” naphtha and “last runnings .” The once- run naphtha is the startingpoint from which are derived the various grades o f benzols

,

solvent naphthas , etc ., by fractional distillation . The specificgravity of solvent naphtha should not exceed I ts compositiou is very complex , including xylols , cumols , homologs ofbenzol , together with some paraffin , and sometimes a little naphthalene. This last-named substance is O ften obj ectionable, as itacts upon some rubbers like animal oil . Naphtha derives itsvegetable solvent power largely f rom the xylol present in it .This is to-day removed and sold by itsel f as a solvent , though theresidual naphtha is proportionately reduced in value .

Lascelles—Scott , after exhaustive experiments , thus describesthree naphthas used in England in rubber factories . P etroleumnaphtha in its solvent action on rubber showed slight action inthe cold or under gentle heat . V iscid masses and semi- solutionswere formed , but these solutions did not dry well . The samenaphtha had almost no solvent action on pitch . Shale naphthawas use ful only in dissolving Madagascar rubbers , and had noaction on pitch , while coal- tar naphtha caused almost any rubberto swell quickly and , after gentle heat , eff ected a good solution .It also readily dissolved pitch, forming a deep-brown solution .

The problem that confronts rubber manufacturers as arule is the solution of gums that are more or less heavily compounded , which is an easier problem than the solution of crude

P ETROLEUM S OLVENTS 241

rubber that perhaps has not been broken down in any way. A t

the same time it is customary in many cases to apply a little heatduring the mixing. The follow ing table relates to petroleumnaphthas . The C naphtha has not only the greatest solventpower

,but it i s easier to evaporate after it has dissolved therubber compound . B and A require a certain amount of heat

to vaporize them :Spec ific Degrees BoilingGravity . B eaumé. Points .

65 deg rees F .'

85 120 deg rees F.70 180 deg rees F.67 220 deg rees F.

A . Naphtha 65 300 deg rees F.Naphtha is more largely used in the proofing business than

any other solvent. It is a general solvent for cements , and quantities of it are used in almost all l ines of rubber work wherethere is any making up of separate pieces after calendering .I t i s therefore necessary that a good grade be used in consideration’of the danger that may come from fires caused by the explosion or easy ignition of low—grade solvents . O dorless naphthas are those from which naphthalene , a solid white body, hasbeen removed , as it is the presence of this body that causes thestrong smell . Naphtha treated by sulphuric acid acquires arather pleasant odor as a consequence . I t is O ften mixed withother solvents— for example , with O il of turpentine— and i s foundthus to have a better solvent eff ect on the rubber.

P ENTAN E .— A hydrocarbon of the paraffin or methane series .

A colorless , volatile liquid which occurs in petroleum. B oilingpoint 98 degrees F . P entane is used with paraffin wax and indiarubber in water- repellent compounds . Specific gravity

P ETROLEUM SOLVENTS - The petroleum oils are by far thecheapest oils in commerce. They are solvents for rubber andare more extensively used for that purpose than any other class .In defining petroleum oils it i s hard to make definite distinctions , for every oil is a mixture of many separate chemical substances , and the names used to designate them in the trade andthe tests used are indefinite and the products of no two manufacturers agree in name or test.

P etroleum oils consist in the main of hydrocarbons ofseveral series , and a large number of each series is found in each

Ckind as It 18 taken from the ground .


The first oil s Obtained from P ennsylvania and West Virginiaconsisted of oils of the paraffin series exclusively, having thegeneral formulaC

nH2n+ 2

. This seri es begins with marsh gas withone carbon atom and goes up to the paraffin waxes with manycarbon atoms in each molecule , but each compound has the sameratio of carbon and hydrogen as pointed out above .When this O il i s distilled there first passes off a little marsh

gas which is dissolved in the O il , and following this i s a serieso f products up to pentane, which boils at 36 degrees C.

, whichare mostly lost

,though products are sometimes made which will

remain liquid only under pressure and will rapidly evaporate inthe air. F or example , there is a product known as cymogenewhich boils at the temperature o f melting ice and has a specificgravity of 110 Bé.

,and the next higher product is known as

rhigolene,which boils at about 65 degrees F . , or ordinary tem

perature , and has a specific gravity of 100 B e. S ometimes aproduct known as petroleum ether, boiling between these points ,say about 50 degrees C., i s made .

The next product Obtained by distillation of P ennsylvaniaoil i s petroleum ether o f 85 degrees Bé., or gas-machine gasoline ,which is very scarce now. It begins to boil at about 50 degreesC . and contains some that boils at 120 degrees C . This i s sometimes called benzine, but must not be confused with the coal-tarbenzene or benzol .

Then there are a series of gasolines o f diff erent gravities andboiling points . I t was customary to use gasoline of 76 degreesBé., but this product is now almost unobtainable , and that of66 B é., with a boiling point ranging up to 140 degrees C. ,

i slargely used . A fter these products come the kerosenes

,or burn

ing oils , which are not volatile enough to be used for solventswhich have to be later evaporated .

The petroleum trade has clung to the use of the B auméhydrometer as a standard for grading oils , and usually no othercharacteristic of the oil than its B é. gravity is used in the trade .While all the oil used was of the paraffin series

,the B é. gravity

was an indication of its relative volatil ity. This is now of novalue when other hydrocarbons are present .When the O il of P ennsylvania became exhausted the O i ls of

O hio assumed great importance, and these were found to diff er


the enormous increase in demand for gasolines for motorvehicles .

P I N E O I L— Thi s is made by distillation from dead woodof the Scotch fir (P inus sy lvestr is ) . I t has an unpleasantempyreumatic Odor. This is fatal to its Use when it appears inthe finished goods , but when it is removed the odor can betolerated in the workrooms , with proper mechanical ventilation .P ine oil i s also made from wood at the same time as turpentine , and is a less volati le compound . B oth of these O ils willdissolve rubber better than petroleum naphthas and as well ascoal-tar products .

P ROPYLEN E CHLORIDE—The specific gravity is and theboiling point 207 degrees F .

RH I GOLEN E .-See Naphtha .

ROSI N O I L— This is obtained by subj ecting rosin to dry distillation, the specific gravity of the resultant oil ranging f romto I t is rarely used as a solvent for rubber , in the

ordinary meaning of the te rm . A s a matter of fact , it is not agood solvent for crude rubber. F or compounded rubbers , however

,it works well and is o ften used , particularly in connection

w ith pseudo-guttas . In certain insulating experiments , where athin sheet O f gutta-percha covered the conductor, and the outergutta-percha tube was ful l o f rosin oil , it gave , according toP ro fessor D. E . Hughes , a higher insulation test thangutta-percha alone . P rofessor Hughes used rosin oil quite thickand viscid , and added resin and a sol id residuum Obtained fromthe distillation of palm oil . Rosin oil in rubber compounding

,

however, softens the compound in a marked degree .SHALE SPI RIT i s the solvent used in the Scottish waterproof

ing establishments . I t is a product o f the Scottish paraffin O ilindustry.

TETRACHLORIDE O F CARBON .— See Carbon Tetrachloride .

TETRA CH LORM ETH EN E B EN ZEN E SUBSTI TUTE IS an excellent solvent, boiling at 75 degrees C . Not easily ignited ; ofpleasant smell ; made f rom chlorine and carbon bisulphide .

TH I ON .—A substitute for bisulphide of carbon , manufac

fured in England,said to mix excellently with chloride o f sul

phur, and is non-poisonous .

TOLUOL— TURP ENTI NE O IL 245

TOLUOL OR TOLUEN E .—That oil which is distilled f rom coal

tar at a temperature of 230 degrees to 234 degrees F ., alsocalled methyl benzene and toluole . Specific gravity It

resembles benzene in outward appearance . Much commercialbenzol contains toluene , which makes it a far better solvent forrubber than benzene itsel f , as it dissolves the rubber in five

sixths of the time . The solutions are more mobile ; it has ahigher boiling point ; and , g iven a quantity of the solvent, willdissolve more gum even at low temperature . It leaves a moresolid deposit of rubber than benzene, and does not induce head;ache or sickness .

TURPENTI N E (crude ) i s known as an oleo resin , and is o fabout the consistency of f resh honey. There are more than adozen varieties on the market, the more common being B ordeaux , Venice , Canadian , and American . A fair qual ity of turpentine oil should begin to boil at 155 degrees C . or 3 11 degreesF . The distillation of crtide O il of turpentine by steam leavesordinary rosin . O il of turpentine is used in certain waterproofcements

,in connection with both gutta-percha and india rubber.

Where O il of turpentine is necessary for rubber work , it is wellto have it free from the c onsiderable percentage of water whichit invariably contains . This is done by a treatment with sul

phur ic acid , or by recti fying it over burnt lime . Turpentine ,particularly that known as Venice turpentine , i s o ften used inconnection with linseed O il and sulphur in the production o frubber substitutes . P rofessor Tilden showed , some years ago ,that what appeared to be pure india rubber could be obtainedfrom turpentine ; indeed , he announced that he had produced iton a small scale . The same thing was also observed by B ouchardt. Venice turpentine i s obtained from Switzerland , whereit i s procured from the Lan'

x Europea, or larch . The genuineVenice turpentine is of the consistency of honey, cloudy, yellowish , or Sl ightly greenish . It i s entirely soluble in alcohol .The commercial Venice turpentine is a factious substance , usuallyquite brown , and is prepared by dissolving rosin in oil of turpentine . Venice turpentine i s largely used in cements . B or

deaux turpentine is the ordinary turpentine of commerce,get

ting its name from the port in F rance whence it i s exported .TURPENTI N E O I L OR SPI RI TS O F TURPENTI N E has a specificgravity O f I t i s colorless

,transparent

,with strong odor

,


and bitter taste . I t i s insoluble in water, on which it floats,

but readily soluble in strong grain alcohol , ether, ‘ and the fixedand essential O ils . I t is an excellent solvent for sulphur, resin ,and india rubber. Spirits o f turpentine , with wood spirit alcohol

,aniline, and nitric acid is used in surface work on vulcan

ized india rubber. The earliest records of india rubber speakof this oil as a solvent ; indeed , the whole secret of rubber compounding for a number of years , when the great Roxbury RubberCO ., of B oston , was running, was the solution of india rubberin turpentine . I t is used in solutions that are expected to besticky, and to dry slowly.

VULCOLEI NE i s a liquid o f English origin , and is put uponthe market at about the same price as carbon bisulphide , andused for a solvent for '

ind ia rubber. It leaves on evaporationa perfectly tough and elastic film, quite unlike that le ft by coaltar naphtha , or the usual solvents . I t mixes instantly withchloride of sulphur, and is intended to replace bisulphide ofcarbon in the coldcuring process . I t has no bad smell

,nor is

it unhealth ful .WOOD SPI RIT.

—See A lcohol .X YLOL. —A colorless , somewhat aromatic , inflammable , oily

liquid distilled f rom coal tar and wood tar ; also called xylene .I t is similar to benzol and toluol . Specific gravity

248 M I S CELLANE OUS P RO CESSESHard rubber may be decorated by means of pigments mixedwith Shellac and applied to the given surface with a brush . The

surface then is to be pressed with some force against a hotplate of metal , whereby the colors aremade to appear as thoughintegral with the rubber.Wood coated a sheet of vulcanized rubber with chloride

of silver, the idea being to use it in dental plates . Various processes have also been brought out for the surface treatment of ,rubber with gold leaf , bronzes, etc ., usually applied in the formof powders , in the manner in which 'flock (powdered fiber ) i sapplied . Truman also patented a process for electro-gildingrubber dental plates after they were finished .

Goodyear dusted unvulcanized rubber surfaces with plumbago or powdered metal , to make them electrically conductive ,pressed the dust in , and then elect roplated upon it .

The embossing of india rubber surfaces has been practicedalmost S ince the invention of Goodyear’s “triple compound .” I t

i s really nothing more than a light surface molding. This isdone sometimes by embossing rolls , the rubber being cured afterthe impression i s taken

,and sometimes by being vulcanized on

the impression plate .' B ourbridge patented a process for embossing rubber byroll ing it tightly on a drum with embossed paper or bookbinders’ cloth , and semi-curing it in that form , preferably byboiling in water at a temperature f rom 212 degrees to 220 degrees F . This boiling Operation was not really vulcanization ,but simply a means of setting the rubber, which was afterwardmade up into goods and cured .

In producing sheets of india rubber for the manufactureof tobacco pouches , balls , balloons, etc ., by this process , theSheet is calendered on sized cloth , partially vulcanized , printed ,coated with transparent india rubber, the goods made up, and i

the vulcanizing process completed .P rinting on inflatable thin rubber films , such as toy bal

loons , may be neatly done by applying the inflated article to theinked type or electrotype .

A great many beauti ful colors are added to india rubbersurfaces by coating the sheet with a thin adhesive solution , dusting it over with colored flock , and then vulcanizing. B y this

COLORED DES I GNS F OR F A B RI CS 249

process any color can be given to rubber surfaces which are tohave a cloth- like appearance .

Kelley produced a bronzed appearance on rubber-coatedfabrics by means O f a roller partly immersed in a trough holding the dye

,curing either by dry heat, or by chloride o f sulphur.

H i s solution consisted of 2 ounces alcohol spirits , 1 ounce woodnaphtha

,10 drops nitric acid , 1 ounce spirits of turpentine (with

sufficient aniline dye to make the desired color) , 4 ounces liquiddyeing

, 3 pounds rubber composition . He also impregnatedfarina with aniline solutions , dried it, and mixed it in the compound .

In certain dyeing processes lakes are necessary. A caout

chouc lake is made by steeping 1 ounce of P ara rubber in a quartof light camphor O il , exposed to the sunlight for several days .This is said to be excellent for binding colors .

Matthew’s process for producing colored designs forproofed fabrics i s to first coat the fabric in the ordinary manner with pure or colored india rubber . When the design is to beprinted on a black or dark ground , the last coating is mixedwith starch or some powder that will render it non-adhesive , andto an extent absorptive . The fabric is then partially vulcanized ,when the designs are printed on the desired surface . The vul

canization i s finished preferably by using chloride of sulphur.Colors suitable for admixture with rubber should answer

the following requirements : they must be unaff ected by water,acids , alkal ies , or chloride of sulphur. F urther, they must notbe aff ected by sulphur at temperatures ranging f rom 200 degreesto 300 degrees F . The colors must not be soluble in or affectedby naphtha or other solvents used in rubber work . A ccordingto F rankenburg, his invention of aniline lakes answers all theserequi rements . H i s description is as follows

(A . ) Lakes prepared f rom acid aniline colors . I havefound that by converting any of the acids or suphonated anil inecolors into compound lakes , such as barium-alumina , calciumalumina , barium-chromium, or calcium- chromium lakes

,colors

are obtained answering all the above requi rements,and there

fore eminently suitable for the dyeing of india rubber, waterproof , and other articles . The aniline dyes best suited for theproduction of these lakes are those known as azo or di-azo col

250 M IS CELLANE OUS P RO CESSESors . F rom colors o f this description I prepare lakes in the following manner : 50 pounds of orange I I ., or any other suitableazo or di-azo color, and 112 pounds of soda crystals are dissolved in 100 gallons of water at 170 'degrees F . This solutionis then precipitated with a solution of 150 pounds of bariumchloride . The precipitate is kept boil ing for hal f an hour . I t

i s then le ft to stand , and washed several times with fresh water.Eventually a solution of 40 pounds of alumina sulphate is addedvery gradually, when a bright , fast , and flocculent lake is obtained , which , after filtration , drying, a nd pulverizing, is readyfor incorporation with the india rubber dough . I t is evidentthat a great many variations o f the process may be devised , butin every case the important point is the conversion of the anil ine dye into one of the above-mentioned compound lakes . A s

regards the proportions given above , they are , of course , sub

j cet to such variations as are in accordance with the molecularweights and the commercial purity of the materials used , as wellas with the particular properties and qual ities to be imparted tothe lakes for the purpose they are intended to serve . Using inthis manner the numerous azo and di -azo dyes a very greatvari ety of lakes may be produced , comprising all conceivableshades , and all suitable for the dyeing of india rubber articles ofevery description . The lakes prepared from the acid oxy-ketonedyes and most of the natural dyes are very suitable for this purpose , owing to their indiff erent and dul l Shades .

(B . ) Lakes prepared from basic coloring matters . A

large number of lakes derived from this class of dyes are alsosuited for the dyeing of india rubber articles , although many ofthem are lacking in fastness to l ight acids and alkalies . To produce a perfect compound lake from these dyes tannic-acid andantimony

,along with aluminum and barium, are used for the

complete fixation and precipitation of these lakes . The following proportions give good results : soda carbonate , 128 pounds ;barium chloride

,110 pounds ; thioflavine , 25 pounds ; tannic acid ,

20 pounds ; acetate of soda, 20 pounds ; sulphate o f alumina , 100pounds . These colors can be made faster by adding to them asmall quantity of antimony potassium- ta rtrate . The proportionsO f tannic acid , sodium acetate, and tartar emetic used in thisprocess vary considerably with the diff erent basic colors , such

252 M I S CELLANE OUS P RO CESSESsometimes in combination

,considerable judgment being meces

sary in selecting those which have an affinity for or are readilyabsorbed by the fibers of particular fabrics , influenced also bythe nature and color of the fabric. In some cases india rubber,gutta-percha , maltha , asphaltum, resin , and artificial gums arefound valuable in small proportions , and in conjunction with thesubstances already mentioned .

In order to apply the waterproofing substance , it is formedinto slabs . The fabric is carried on a reel supported in bearingsbetween suitable frames , at the opposite end of which is a hollow cylinder mounted upon carrying rollers and supported laterally by side rollers . This cylinder is filled with water. The

slab of the compound , wider than the fabric to be coated , i s fixedin a holder above the cylinder. This holder is so arranged thatthe weight presses the slab against the cylinder. The fabric i sthen drawn from the reel over and under tension bars , under asupporting roller

,between it and the rubber cylinder, and around

the cylinder and under the slab , then over the guide roller andinto a drying machine . The friction of the cloth wears the slabaway and uni formly deposits it upon the cloth while in the drying machine , the heat melts the waterproofing compound , and iti s absorbed by the fibers

,which are thereby rendered waterproofor water- repellent .

O ther formulas for shower-proofing and waterproofing areof interest in this connection and a few are givenA German waterproofing compound : alum , 10 pounds ;

sugar of lead , 10 pounds . Di ssolve in hot water and allow theprecipitate to settle . Dilute the clear liquid with 120 ° gallonswater and add 2 pounds isinglass in solution . The goods aresteeped in this solution 8 or 10 hours .

A n American Shower-proof compound : liquid silicate ofsoda , 1 gallon ; white oxide of zinc , 1 pound . I f the fabric i sto be colored, add coloring matters . The mixture may be appliedto fabrics hot or cold , by means of a brush or by immersion ofthe fabrics , which are afterwards to be run between rollers .

A nother American compound : dissolve separately, 1%pounds alum (in hot water) , 10 ounces acetate of lead (in hotwater ) , and IV,

» pounds carbonate of magnesia (in hot water ) .They should aggregate about 3 1 quarts . A dd the acetate of lead

SHOWER-P RO O F COM P OUNDS 253

to the alum solution , and then the carbonate of magnesia ; afterwhich 10 quarts l iquid as above and 1 tablespoonful white gumarabic . S tir V2 hour ; let stand 24 hours . skimming now andthen ; in 48 hours the first mixture will be ready. Lay the fabricin a vessel and pour liquid over it, beating the fabric well andremoving it within an hour.

A third American shower-proof compoundA . Carbonate of soda 16 parts .

Lime 8 parts .

Water 32 parts .

Boi l 30 minutes, let settle and pour O ff the c lear ly e.

B . Glue or g elatine 3 parts .

Linseed oil 3 parts .

A dd after soaking g lue in cold water 12 hours .

C. Tal low (or other animal fat) 16 parts .

Ros in 8 parts .

Melt tog ether.To (A ) boi l ing hot add hot (C) , then pour in (B )

and stir hot unti l wel l m ixed .

D. Sulphate of aluminaA cetate of lead V.» pound .

lBoi l ing water 8 gal lons .

Let settle and draw O ff clear l iquor for use. To 1 gal lonwater add 1

2 ounce of first product for bath for cotton goods .

A dd My, ounce for s i lk or woo l . Immerse 24 hours or more, thensix hours or more in second compound (D) .

P roofing compoundM ixture 1.

—Dissolve in water,50 parts alum ; also dissolve

in water, 35 parts sugar of lead ; mix .M ixture 2 .

—Combine 17 parts paraffin and 35 parts benzine ;drop into this 17 parts caoutchouc . S tir until well dissolved .

M ixture 3 .-To the c lear ‘

decanted l iquor from the abovemixture , add 8 parts alcohol and 4 parts eau de cologne (or oilof lemon ) .

A n English compound for waterproofing textile fabricssugar soap , 1 pound ; water, 16 gallons . Soak articles in themfor 6 hours ; drain , but do not wring them ; and place them inthe following solution : alum,

1 pound ; water, 16 gallons ; soakagain 6 hours

,take out and dry without wringing.

A nother English compound for waterproofing textile fabrics : 'concentrated size, 8 pounds ; aluminum sulphate , 5 pounds ;barium chloride , 6 pounds ; water, 16 gallons . A fter coating

,

varnish with the following : M elt together 22 pounds Colophony,4 3 -5 pounds crystallized soda , and 11 pounds water. Then add

254 M I S CELLANE OUS P RO CESSESammoniacal fluid , 5% pounds{and water, 55 pounds ; or : borax ,6 pounds ; shellac, 6 pounds ; and water, 40 pounds .

A German compound for waterproofing woolens : dissolve100 pounds alum in moderate quantity of boiling water ; soak 100pounds glue till it has taken up twice its weight of cold water,then apply heat to dissolve it ; sti r 5 pounds tannin and 2 poundssoluble glass well into the glue , then add the alum solution .Enter the goods at 80 degrees C., and steep 30 minutes . Takeout and drain several hours , stretch on a frame, and , when dry,calender.

A German shower-proof compound : stir 9 pounds caseinwell in 32 quarts water, adding little by little 25 pounds of slakedlime . A dd a solution of 4V2 '

pounds soap in 26 quarts water.F ilter and treat the cloth with the liquid . Dress with a

dressing of acetate of alumina , by which the casein i s renderedinsoluble in the fibers of the cloth . A fter two applications, rinsethe goods with hot water, press strongly, and dry .

O ne process for waterproofing threads and yarns used inweaving ducks and other fabrics is in two parts, the first o f whichrelates to a tanning mixture in which the yarns are immersed

,

consisting of : birch bark, 14 pounds ; bichromate of potash , 1pound ; chloride of calcium, V2 pound ; tar 1 pint ; solution ofalkali , 2 pounds . The threads are first boiled in a 5 per cent .solution of alkal i to destroy perishable matter, after which theyare immersed in the tanning liquid and dried . The second partconsists of preparing or dressing the threads with the followingcompound : poppyseed oil , 2 gallons ; india rubber solution , 2pounds ; red oxide of mercury, 1 pound ; resin , 28 pounds ; beeswax, 28 pounds ; palm oil , 14 pounds . The threads after thistreatment are wound on reels for weaving.

F orster, in 1847, made a water- repellent compound in whichhe used spermaceti , wax , and stearin , while three years priorto that Townsend used two solutions to accomplish that end ,the first being water, calcined B ritish gum, white soap , logwoodliquor, and alum ; the second being water, sulphate of zinc , calcined B ritish gum, and palm soap .

The kyanized cloth process i s well known in connection withpreserving fabrics

,the treatment being with a mixture of cor

rosive sublimate,chloride o f zinc , pyrolignite of iron, oil of tar,

256 M I S CELLA NE OUS P RO CESSESDEODORIZATION .

TH E odors that cling to vulcanized rubber goods and togutta-percha are O ften -very obj ectionable

,and the following

processes are given for deodorizationCattell’s process : F or every pound of well- cleaned gutta

percha take 15 pounds of the following solution benzol , 1 gallon ; alcohol , 1 ounce ; glycerine , 30 drops . O r : benzol , 1 gallon ;nitrate o f the oxide of ethyl , 30 drops ; heat in a closed vessel to110 degrees F . The gutta-percha is recovered by cooling tobelow 32 degrees F . , and pressing or . by distill ing off the solvent, or by precipitation with fusel O il .

F reeley’s process : dip vulcanized rubber goods in a solution

of : salicylic acid,20 grains ; alcohol , 56 pint . This will deodorize

them, but goods will be toughened and the deodorization increased by subj ecting goods to a bath in hot or cold solutioncomposed as follows

(A ) O akbark, 50 pounds ; hemlock bark, 50 pounds ; sumacbark, 50 pounds ; water, 900 gallons .(B ) Solution as above , 2 gallons ; salicylic acid , 20 grains ;large tablespoonful of Russian jackten extract, dissolved in 2

pints o f alcohol , 1 pint o f ether, and 10 grains o f salicylic acid .B ourne’s process : The articles to be deodorized are placed

between layers of charcoal and heated from 120 degrees to 150degrees F i f unvulcanized ; 180 degrees F .,

i f partially vulcanized ; or 212 degrees F ., i f completely vulcanized . Heat for sixhours or more .

Lavater and Tranter’s process : Subj ect the articles to aboiling in potash , then to a vacuum , then to a pressure o f airscented with some essence . They claim the extraction of the sulphur from the pores of the rubber in the form of sulphuretedhydrogen and its replacement by perfumed air.Charles Hancock’s process : To remove the odor o f guttapercha , steep it in the following solutions(A ) Soda or potash , 1 pound ; water, 10 gallons .(B ) Chloride lime , 1 pound ; water, 10 gallons .

De la Granj a’s processI od ineP ermanganate o f potassaI od ide of potass iumGlycer ine

P RESERVA TI VE P RO CESSESDe la Granj a’s process (Continued )

Sulph ite of soda

Sulph ite of l imeSulphite of potassaWaterSoak rubber in a solution composed as above, in a close

earthern vessel , 24 hours , the solution being cold . Then heat thesolution gradually to boiling point and uncover the vessel untilo f weight of solution evaporates . When the solution coolsremove the rubber.

The Traun Rubber CO . patented a process for adding powdered perfumes to india rubber, the stock being used for dentaldam

,dress Shields , and the l ike .

P RESERVING RUBBER GOODS .

TH E deterioration of vulcanized rubber goods is often aserious matter, where it i s necessary for some time to keep themin store . Wherever possible , they should be kept in a cool , darkplace, and away from warm currents of dry air, and f ree f romcontact w ith oil of any kind . Soft rubber articles are often preserved by being kept submerged in water. Such articles wouldnaturally be smal l in size and contain no exposed fabric ormetallic parts . A typical list would be , tubing, catheters , bulbs ,stoppers , etc .

The caus e of brittlenes s A hrens looks for not in the methO ds of s toring but i n unsuitab le mix ing s and wrong vul canization.

Where one is forced to use chemically active fillers , sub

stances should be added to retard oxidation . Using petroleum ,

benzol , aniline, pyridine , etc ., to regain the elasticity of hardened rubber has, in the end , the opposite effect. The softeninglasts only as long as the solvent is present ; after its disappearance there is hardening aga in and an acceleration of the degenerating process.

I t has been advised that such goods as druggists’ sundriesbe stored in an air- tight receptacle in the bottom of which isplaced a vessel containing benzine

,which is allowed to evaporate

slowly. Kreusler and Bude in Der Techniker recommend thedipping of the articles in a paraffi n bath , heated to about 212degrees F . This does not injure the color or the appearance

,

but is said to enable the goods eff ectually to resist both light and .

258 M I S CELLANE OUS P RO CESSESatmospheric influences . F rom its well-known softening eff ecton india rubber, however, paraffin is likely to be used with cons iderable care by rubber manufacturers . In the line of mechani

cal goods,Tum er patented a process for treating both hose and

tubing with carbolic acid, either during its manufacture or aftervulcanization, in order to preserve it. Torrey also saturated duckwith carbolic acid before it was made up into hoSe.

M owbray’s process for preserving rubber in valves : The

use of 20 pounds of india rubber, washed and cut fine , in connection with 5 to 10 pounds of naphthalene ; digest 24 to 48 hours ,at 180 degrees to 230 degrees F . M asticate in a machine heatedto 212 degrees F .

,until it forms a p lastic homogeneous com

pound . I f other substances are to be added , treat as follows :1. Soluble matters (sulphur, antimony , resins , etc . ) dissolvein naphthalene, melted or boiling, and add to above naphthalizedcaoutchouc at temperature of 240 degrees F .

2 . Materials insoluble in naphthalene (oxides of lead andzinc, chalk, etc . ) deprive of moisture and heat to 212 degrees F .

and add to naphthalized caoutchouc .This compound can be used for soft or hard rubber

,accord

ing to the proportion of sulphur used . The obj ect i s to preservethe elasticity O f rubber and prolong its durabil ity.

Trueman’s process for preserving india rubber, and fibersthat may be used with it , employs the peroxides of manganeseand lead and the black oxide of copper

,all o f which have the

property of decomposing O zone in great quantity, and converting it into oxygen . The inventor believes that ozone is the activeagent in producing decay, and , by changing it into oxygen , hearrests such decay. In applying these oxides

,he mixes them

with ozocerite or tar.E lworthy patented a process for storing rubber goods in a

receptacle filled with nitrogen , hydrogen , marsh gas , or carbonicacid gas . This was recommended especially for rubber goods inIndia .

B enton (American patent ) describes the following : A composition for preserving india rubber,consisting of one part tur

pentine , as much camphor gum as the turpentine will readily dissolve, and one part linseed oil proportioned to the combined parto f turpentine and camphor gum .

M I S CELLANE OUS P RO CESSESpractice is necessary to judge properly the heat of the i ron afterquenching, that it may not continue melting the interior of theroll and produce a cavity or unattached spot .

SOLID TI RES To STEEL RI M S .— The steel rims for solid

motor- truck tires are provided with coarse grooves to add increased surface and protection against side slip o f the hardrubber ply uniting rim and soft rubber. F requently the rims areelectroplated with brass for chemical union with the hard rubberand sometimes the grooves are undercut or dove- tailed in formto add an interlocking grip . The rims are brushed and cleanedwith naphtha , cemented with hardrubber cement and , whenthoroughly dried

,the hardrubber ply is forced into contact with

the cemented surface with complete exclusion of the air between . The hardrubber surface is rendered adhesive withcement and the softrubber body of the tire applied . Vulcanization in a mold under extremely heavy pressure in a vulcanizerpress renders the attachment o f steel and rubber permanent .

The Garrity and A very patented process is as followsnitric acid (41 degrees B eaumé) , 10 gallons ; muriatic acid (22degrees Beaume) , 10 gallons ; mix and add pure tin, finelydivided , 10 pounds . Immerse the iron for 8 seconds

,remove and

dip into weak solution sulphuric acid , then wipe with a woolencloth . Then apply with brush , or otherwi se , the following compound : rubber cement, 7 gallons ; l itharge , 6 pounds ; and sulphur, 3 pounds . A pply vulcanizable rubber compound at once ,and vulcanize .Hall’s process :Water, 100 quarts ; caustic potash , 10 pounds ;cyanide of potash , 2 pounds ; sulphate o f copper, 2 pounds ; sulphate of zinc, 2 pounds . Thepickle and bath are made of water

and about 10 per cent . sulphuric acid , the tub being lined withbrass plate .

A dam’s process : A weak solution of sulphate of copper ismade— say 2 or 3 ounces o f the crystallized salt to the gallonand this solution may be acidulated with sulphuric acid— sayabout gill of strong acid to the gallon . F or a fine film for“dipping” a rticles of i ron , steel , or tin , to which the rubber compound is to be applied , i f the metal is copper, it should first becoated with tin , nickel , or i ron .

GA S P RO OF ING 261

The shellac process calls for a cement made of shellac steepedin ten times its weight of concentrated ammonia, the solutionbeing allowed to stand three or four weeks . This solution i spainted on the iron, allowed to dry, and the rubber vulcanizedupon it.

The Daft patented process consists essentially in heating therubber in contact with metal containing an alloy of antimony.When the rubbe r is to be attached to iron or steel the surface iselectroplated with copper, zinc and antimony alloy.

GA S P RO OFING.

B EF ORE india rubber reached its present value in the arts ,and before coal gas was generally known as an illuminant, Mol

lerat Obtained oil o f caoutchouc by distillation and made a finequality of illuminating gas f rom it .

Vulcanized india rubber,whether compounded or pure, ispermeable by gas . In making flexible gas tubing, therefore, it

must be coated or in some way protected in order to make it gastight . The common way of accomplishing this is to cover therubber tube with an outer tube made of glue, glycerin , andbichromate of potash, this covering being protected in turn by awoven fabric. A nother plan for accomplishing the same resultis to have an outer and inner tube of india rubber, between thetwo being vulcanized a sheet of tin- foil .

P ellen rendered india rubber impervious to gas by coatingit with collodion mixed with a very small quantity of castor oilor with a varnish composed (1) of 32 per cent . of gum arabic ,8 per cent . of sugar, and 60 per cent , of water, or (2 ) made from28 per cent . of dextrin , 60 pe r cent. of water, and 12 per cent.of gelatine.

B ousfield rendered vulcanized india rubber impermeable togas by applying linseed oil to it in the form of a varnish , thearticles being heated .

GA S P ROO F I NG F OR B ALLOON S .—The following mix ings arethose approved by Churrel for gas balloons

F or Gas -Tight F abrics .

Fine hard P araP araflfln (66 deg r ees C. )Sulphur (twice s i fted )O xide of magnes ia (twice s i fted )

262 M I S CELLANE OUS P RO CESSESF or Tens ile S trength.

Fine hard P araP araffin wax (66 deg rees C. )Car bonate of magnes ia (twice s i fted )O xide of magnes ia (twice s i fted )Fine sulphur

F or Cold Vulcanized Gas -Tight F abrics .

F ine hard P araP araffin wax (66 degrees C.)

A CTION O F METALS O N RUBBER.

TH E action o f various metals on india rubber has alwaysinterested rubber manufacturers . In the memoirs and proceedings o f the Manchester (England ) Literary and P hilosophicalSociety, 1890-91, William Thomson , and F rederickLewis published an exceedingly interesting paper on this subj ect .They covered almost all of the metals that are likely in any wayto come in contact with rubber surfaces , and proved what haslong been acknowledged by rubber manufacturers : that the actionof copper is most harmful . The metals that have no action at allon rubber are gold

,silver, bismuth , antimony, arsenic , tin , chro

mium , i ron , nickel , cobalt, zinc , and cadmium . Those that actonly in a slight degree on rubber are lead , aluminum, palladium,

and platinum .

O f the salts of metals that are very destructive , copperstands first, manganese oxides and nitrates of silver being, however, almost as bad . Several other nitrates have also an injurions eff ect, although not as much so as those just mentioned .They are the nitrates of ammonia

,uranium, sodium, and iron .

A ccording to N . P oden , a well-known English expert ,proofed goods in browns have caused him more trouble bydeterioration than any other colors —more than black , even— andit i s to be noted here that blacks as a rule are viewed with distrust by manufacturers , because it i s bel ieved generally thatcopper salts are used in the dyeing. M r . F oden instances thetime when brown tweeds were used largely, and when mostmanufacturers experienced a great deal of trouble with them , asthe browns showed early signs of decay, while the gray s remainedsoft and flexible . M r . F oden suggests that , as certain dyers use

264 M I S CELLANE OUS P RO CESSESages in the various grades of P ara rubber, also determined by thepractice of American manufacturers :

F ine Med ium Coar se

15 to 17 16 to 18 20 to 2515 to 17 16 to 18

Madeira 15 to 18 16 to 19 20 to 2516 to 17 17 to 18 18 to 22Upr iver 16 to 18 17 to 19 18 to 25

Matto Grosso 16 to 18 17 to 19 20 to 28A ng ostura 16 to 18 17 to 19 25 to 30

16 to 18 18 to 20 25 to 30I taituba 17 to 18 18 to 19 20 to 25I s lands 18 to 20 18 to 22 25 to 35Cameta 30 to 35

The shrinkage of Mangabeira (P ernambuco ) thin sheet isabout 25 to 30 per cent . ; thick sheet , 30 to 35 ; ball , 20 to 25.

Caucho (P eruvian ) slab, 30 to 40 ; sheet, 30 to 35 strip , 25 to35 ; ball, 20 to 25.

The better grades of centrals shrink from 25 to 30 per cent .other grades, generally from 30 to 40 .

AF RI CAN S.

The Gold Coast sorts (including A ccra , Cape Coast , Saltpond, A ddah , Quittah , and A xim ) range about as follows : buttons or biscuit, 20 to 30 flake , 30 to 35 ; lump , 30 to 40 ; niggers ,20 to 35.

Cameroon ball , 18 to 25 ; clusters, 18 to 28.

Lagos buttons, 25 to 35 lump , 30 to 40 ; strip , 25 to 35.

Congo buttons , 25 to 30 ; ball NO . 1, 20 to 25 ; ball No. 2,

25 to 35 Upper Congo ball and strips , 20 to 35 red ball , 18 to22 ; Equateur small ball , 16 to 20 ; mixed ball , 18 to 22 ; Loporismall ball , 16 to 22 ; Kassai black twist, 18 to 22 ; red twist, 20to 25 ; ball , 20 to 25.

Benguela (and Loanda ) sausage, 16 to 20 niggers , 18 to 20.

M ozambique (including Lamu) ball No. 1, 10 to 15 ; ballNo. 2, 15 to 25 ; ball No. 3 , 25 to 35 ; sausage, 20 to 35.

Madagascar pinky, 30 to 35 Majunga , 30 to 35 black, 30to 40 ; niggers, 30 to 40.

EAST I NDI AN .

A ssam No. 1, 10 to 15 No. 2, 20 to 30 ; No. 3 , 30 to 35.

P enang, No. 1, and Java No. 1, 10 to 15 per cent . ; othernumbers same shrinkage as A ssam .

SHRINKA GE OF RUB B ER 265

E . Chapel gives this table of percentage of shrinkage12 Ceara

P ara, coarse 25 A fr ican bal lLoando 17 Madag ascarColombia 20 A ssam

22 GaboonGamb ia 24 Borneo

TO F I GURE SHRI NKAGE I N CRUDE RUBBER.

I t is strange that there should be a divergence of opinionand method in arriving at the net cost of rubber. after washing,sheeting, and drying it, yet such is the case . To assist those whohave not studied this question , the right and the wrong way offiguring on shrinkage is given here . Take, for instance, anaverage-priced rubber :

Example A .

100 lbs. rubber at

20 lbs. shr inkage= 20 per cent., or 1-5th.

80 lbs., net cost as above.

80

200

160

400400

Some persons , however, figure in this way °

Example B .

100 lbs . at lb.

Shr inkag e 20 pe r cent. : 1-5th.

-5th (10 cents ) = 60 cents.le A .

—Cor rect method— net costExample B .

- Incor rect method—net costDi ff erence

This is a diff erence of 4 per cent . , which , i f it occurs in manufacturing a large amount of good s where rubber i s the greaterpart of the compound , would make quite a difference in the profit .

S P ECIFIC GRAV ITY O F RUBBER.

TH E following records o f the specific gravities of diff erentsamples of india rubber have been collected :Best P ara, taken in d i lute alcohol (Ure )Best A ssam, taken in d i lute alcohol (Ure )Best S ingapore, taken in d i lute alcohol (Ure)

266 M IS CELLANE OUS P RO CESSESSpecific gravity of rubber (Continued )Best P enang , taken in d i lute alcohol (Ure )Caoutchouc (Jul ian)Crude caoutchouc of Ind ia (A driani ) .

Black caoutchouc (A dr iani )P repared from juice in pure state (Faraday )Determined by E . SoubeiranDetermined by P ayen 09 25000

F araday’s general analysis of the latex of the Hevea i s :CaoutchoucA lbuminous extract ive and saline matterWaterThe specific gravity of the latex quoted wasThe crude rubber itsel f is made up of the following generalcomposition : carbon , hydrogen ,

P UNCTURE FLUIDS A ND TIRE FILLERS .

CAMPBELL’S A ND CUSHMAN ’S P UN CTURE F LUID— A mix

ture consisting of water, 2 quarts ; granulated cork , 4 ounces ;powdered cork, 2 ounces ; F rench chalk , 1 pound ; white lead , 8ounces ; and gum arabic , 2 ounces . Canadian patent .

CY CO i s a popular compound , said to serve as a preserver oftires as well as healer of ti re wounds . I t is made of vegetablegums that will not harden ; neither will it interfere with vulcanizing in the event of a large rupture .

Dow’s I N N ER TUBE F I LLER— A mixture o f paste andfeathers held in a continuous pocket that covers the tread o f theinner tube .

ELA STE S .— A n English compound made of glue , glycerine ,

and’ chromic salts .EVERLA STI C is a substitute for air

,and by some considered

a good compound . A s a liquid it is forced into the tire untilthe desired pressure is reached , and in a comparatively shorttime it solidifies and is said to become like rubber. It is notaffected by heat or cold .

F AGI OLI,under a B ritish patent, produces a composition con

sisting preferably of these proportions : 1 pint giant cement ,1% pints of rubber solution , and gallons granulated cork .

F RA N KEN BURG’S P UN CTURE F LU ID— Made of dead B orneo ,

oxidizable vegetable O il, and sulphur ; a B ritish patent .I NRI G

,under a B ritish patent, prepares a rubber substitute

from the gelable portions of animals . F i fty parts of such ma

268 M I S CELLANE OUS P RO CESSESdegree of hardness is obtained . The shape and conformationmay also be equally varied .

It i s very light (about 100 pounds per cubic yard of volume ) , i s both gas and water-proof and aff ected only by strongacids . The cost of product ion varies with the price o f cruderubber

,and is rather higher than the final cost o f good soft or

hard rubber. O ne pound of rubber foam has the same volumeas 18 pounds O f solid rubber.

A variety of practical applications is claimed for rubberfoam , due to its bulk and cellular structure . The l ist includesits use as a substitute for cork in li fe belts ; filling for pneumatic ti res and playing balls, imparting resiliency regardless ofpunctures ; insulation of heat and cold in clothing for autoistsand aviators and in walls of refrigerators ; also for upholsteryand other cushioning purposes .While not affected by acids generally, rubber foam will dis

solve in ammonia , which can be used to soften hard foam tofacilitate working it. When the ammonia is evaporated hardfoam regains its original hardness . I t i s said to be susceptibleof fireproofing .

RUB B ERI N E .-A special solidi fying liquid tire filler made in

England, very largely used for fill ing the tires of armored cars ,lorries , kitchen cars , and ambulances of the Entente A ll ies, forservice on the battlefields of the Great War . A n interestingpoint i s that pneumatic ti res returned from the front for refilling, although riddled with shrapnel bullets , had served their purpose until the car got safely back to its base .

SCOTT’S P UN CTURE F LU ID.

— F i fty parts milk, 17 parts i singlass, 200 parts gelatine, 10 parts camauba wax, 3 parts formal

dehyde , 1 part gum ammoniacum. O f B ritish origin .SUBER’S F I LLER—O ne ounce camauba wax , V2 ounce gum

tragacanth , 12 ounce water. A dd glue and mix in steam .

TI RE LI F E — A ti re filler of the glue and glycerine kind .

CHA PTER XV.

SYNTHETIC RUB B ER.

TH E researches on the chemical constitution of caoutchouc ,or rubber, and the sources and processes available for its '

synthesis,have been outlined by B . D. W. Luff in the “Journal of

the Society of Chemical Industry” (O ctober. 16, The

author’s paper may be summarized as followsBetween 1835 and 1840 the study of caoutchouc was under

taken Ou scientific lines by various investigators , including Dalton

,Liebig

,H imly , A . B ouchardat, and Gregory, but in all cases

their work was more or less disjointed . The most systematicattempt to isolate and examine the various products present inthe crude distillate f rom caoutchouc was made by Greville Williams in 1860. He obta ined (1) a liquid boiling at 37 degreesC. to which he gave the name “ I soprene” ; (2 ) a large proportion of a hydrocarbon boiling at 170 to 173 degrees C., whichwas identical with a body previously obtained by H imly , andcalled caoutchoucine— this has since been proved to be d ipentene ; (3 ) a f raction boiling above 300 degrees C., to which hegave the name “Heveene.

”

Gustave B ouchardat in 1879 undertook a detailed investigation of isoprene, in the course of which he examined the actionof hydrochloric acid . He noted that an additional product wasformed , but under certain conditions the action o f the acid resulted in the formation of a solid mass , not containing chlorine ,but having, in fact , the same percentage composition as isopreneitsel f . He described this body thus : “

I t possesses the elasticityand other properties of rubber itsel f . I t i s insoluble in alcohol ,swells in ether and also in carbon bisulphide, in which it dissolves after the fashion of natural rubber. He also noted thaton distillation it yielded the same hydrocarbon as in the case ofthe natural product . This was an important step in the synthesiso f caoutchouc ; in fact, in order to make this complete, all thatwas necessary was to prepare isoprene from elementary materials .A t that time the only source o f isoprene was rubber itsel f .

e

269

270 S YNTHETI C RUB B ER

B ouchardat’s results were confirmed in 1882 by Tilden , whoobserved the polymerization of i soprene . In discussing isoprenehe remarked that one of its chie f characteristics was its conversion into true caoutchouc when brought in Contact with certainchemical reagents . He pointed out that this was of great praetical interest as , i f i soprene could be obtained from some otherand more accessible source, the synthetical production of rubbercould be accomplished . Two years later he succeeded in Obtaining isoprene by passing the vapors of turpentine through a hottube .

The outcome of the work of these two investigators was thatthe caoutchouc molecule was shown to be formed by the unionof a number of molecules of I soprene , and this union or polymerization could be brought about by treating the isoprene withsuitable reagents . To them must be given the major share of thecredit for laying the foundation of the numerous processes sincesuggested for preparing synthetic rubber.

In 1887 Wallach observed that isoprene undergoes polymerization on exposure

,to light w ith production of a rubber- l ike

mass . In 1892 Tilden showed that the material obtained '

in thismanner could be vulcanized with sulphur. The synthesis ofi soprene, and as a corollary, that of caoutchouc, was aecomplished by Euler in 1897.

In 1909 , m g to the rapid rise in the price o f rubber, theproblem was taken up in England in a Systematic manner byP erkin , F ernbach , Weizmann and Mathews and in Germanyby the B ayer and B adische companies . In 1884 Tilden suggestedthat not Only isoprene , but its homologues , should be capable o fpolymerization in a similar manner. This was found to be thecase, and . these bodies , chie f .among them butadiene , form thebasi s of methods for obtaining synthetic caoutchoucs .P RE SENT STATUS O F SYNTHETIC RUBBER P RODUCTI ON .

DR . F . W. H I NRI CHSEN,in the “Zeitschri ft des Vereines

Deutscher Ingenieure ,” discusses the present situation in regardto the synthetic production of rubber or caoutchouc . There i snot to-day the enthusiastic interest in the matter that existed afew years ago

,although it i s one of great scientific importance .

Dr . H inrichsen in his review confines h imsel f to the essentials of the problem , observing that a complete history of its

272 S YNTHETI C RUB B ERC

“

I twas thus Observed independently by Harries and the Engl ish investigators,Mathews and S trange, that polymerization in

the presence of metal l ic sodium proceeds at great velocity andthe resulting rubber differs materially 'in its properties f rom thatproduced by mere heating. The chemists of the B aden A nilineSoda Works found that i f polymerization by sodium is carried on in an atmosphere o f carbonic acid the results are di fferent. A further process worked out by the samecompany isbased on the use O f ozonizers on peroxide as catalizers .

Thus various rubbers may be Obtained diff ering f rom eachother in their properties according .to the nature o f the primematerials and the method of polymerization . The following compilation,

according to Holt, i s a concise resumé of a series ofsuch diff ering rubberlike substances .

RUBBERS FROM BUTA NES .

STANDARD RUBBER (by heating ) - Easily soluble , elastic andcapable of being vulcanized .

O ZON IDE RUBBER— Insoluble, strongly inflatable , very elastic, not capable of being vulcanized .CARBON I C A CID RUBBER .

-Not soluble , not inflatable , moderately elastic, not capable of being vulcanized .

SODI UM RUBBER— Easily soluble , elastic, capable o f beingvulcanized .

RUBBERS FROM I SO P RENE .

STANDARD RUBBER— Easily soluble,elastic , capable of being

vulcanized .O ZON IDE RUBBER— Soluble only after calendering, strongly

inflatable, elastic, capable o f being vulcanized .CARBON I C A CID RUBBER— I nsoluble , not inflatable , elastic ,

capable of be ing vulcanized .SODI UM RUBBER— Easily soluble, not elastic , can be vul

canized incompletely and only with difficulty.RUBBERS FROM DIME THYL BUTANES .

STANDARD RUBBER— E asily soluble, not elastic, capable ofbeing vulcanized as hard rubber only.

O ZON IDE RUBBER— Soluble only ’

after calendering, inflatable ,not elastic, can be vulcanized as hard rubber only.

UTILI TY O F S YNTHETI C RUB B ERS 273

CARBON I C A CID RUBBER— Insoluble , not inflatable, not elastic

,can be vulcanized only with difficulty and is easily oxidized .SODI UM RUBBER— Soluble and insoluble modifications , in

elastic and incapable o f vulcanization .This possibility of Obtaining substances of varying properties

by changing the basic materials and the process of polymeriza

tion gave rise to the hope of producing at will rubbers withproperties adapted to special applications , somewhat as in thedyestuff s industry colors are modified at will . The commercialimportance of rubber synthesis depends on the product equalingnatural rubber in two respects , price and practical applicability.

The price factor depends in the first instance on the manufacturing cost of the hydrocarbons o f the isoprene series whichare used as the basic materials .

P rogress has been made in this field by the B aden A nilineSoda Works , which starts with certain f ractions o f petroleum .

O ther available substances are starch , amyl alcohol , turpentine ,acetylene, etc. With all the processes there are such large quantities of by -

products that their removal or utilization would constitute a problem even more difficult than that of the productionof the rubber itsel f . A t present there is no possibility of seriouscompetition of artificial with plantation rubber as regards price .

A s regards practical utility synthetic rubbers seem to lackthe durability o f natural rubber because the latter, by its vegetable origin, contains a series of associated substances , resins ,albumen, etc ., which undoubtedly have an influence on its durability , for it i s well known that deresinated rubber is much moreeasily attacked by the oxygen of the air than rubber containingresin . P ossibly these associated substances act as protectivecolloids which reduce the vulnerability o f the pure substance .

A further reason why synthetic rubbers are inferior tonatural rubber in mechanical properties is that the former arenot uni form substances , but mixtures . A ccording to recent in’vestigations of Steimmig , in the oxygen splitting of syntheticrubbers there appears in addition to coulinie acid and couliniealdehyde (which , according to Harries , correspond to naturalrubber ) , resinous acid and acetonyl-acetone.

The two last-mentioned substances indicate that in the polymer ization of isoprene, in addition to the -dimethy lcy clooc

274 S YN THETI C RUB B ER

tanes,a smaller amount (20 per cent. ) of the compound musthave been formed by abnormal condensation , which , upon being

Split by means of ozone , furnishes the two components mentioned . The latter have never been found in natural rubber.Until possible to arrange the conditions of polymerization sothat the synthetic rubbers will constitute uni form compounds ,it i s not to be expected that synthetic rubbers will equal naturalrubber in its use ful properties .

Synthetic rubber has been attained as a triumph of chemicalscience and the researches have been a great contribution to ourknowledge . N evertheless , synthetic rubber is not an industrialsuccess , even in Germany under the stimulus o f imperative warneeds .

Therefore the following cautions on the subj ect may stillhave practical value :

Every year there is more or less newspaper prominencegiven to synthetic rubber discovery and discoverers , but so farabsolutely nothing has been accomplished commercially. The

producers of alleged synthetic rubber work along a variety ofl ines . There i s, first and most dangerous , the line o f f raud ,where real rubber disguised is put forth as a cheap syntheticproduction . This procedure has been the means O f extractingmany dollars from the pockets o f the credulous . There is another class O f honest but somewhat ignorant inventors who makeproducts that in some respects are similar to rubber, and whichthey believe are equal to or even better than rubber. They useoils , gums , cellulose, in fact, almost anything that will producea waterproof plastic . These products are O ften of value in connection with rubber and sometimes when used alone

, but neveryet have anywhere near equaled the crude material .

276 VULCA N I ZA TI ON WI THOUT SULP HUR

there can be no essentially new theory of vulcanization . Nevertheless , the nature of the mechanism of the process even y etremains unexplained .

The supporters O f Weber’s chemical theory regard vulcanized solid caoutchouc (ebonite ) as a polymeride of the compound , C1 0 H 1 6 S 2 (16 per cent . o f while others , for instance, E rdmann , consider it to be the thiozonide , C1 0 H 1 6 5 3 , oreven a dithiozonide. O n the other hand , many identi fy the vulcanization of caoutchouc with the process of swelling” of colloids or that of gelatinization or adsorption , that is , with theprocesses of formation of solid or semi- solid solutions .

Some of the supporters of the “mixed” theory consider thatthe sulphur itsel f swells or is adsorbed or dissolved in the freecaoutchouc , whereas other authors assume the preliminary formation of a compound of the caoutchouc w ith the sulphuralthough only in insignificant amount— this compound being thenadsorbed in the still unchanged caoutchouc .

I shall not devote time to the extensive literature of thisquestion , but shall proceed immediately to the conclusions whichresult f rom my observations and my new methods for vulcanizing caoutchouc .

Until now no method of vulcanizing caoutchouc has beenknown in which any organic or mineral compound not containing sulphur is used as vulcanizing agent .2 But the chemical andespecially the physical theories of vulcanization anticipate thepossible existence o f a whole series of such compounds . I decided . to attempt to find substances which may replace sulphurin the vulcanization of caoutchouc .

It was thought that the investigation o f the action of homolognes and analogues of such substances on caoutchouc and thato f the external conditions of the new process—the influence ofdiff erent admixtures , accelerators , etc — might elucidate the mechanism o f vulcanization itsel f .

This task has now been completed , and two new methods forthe hot vulcanization of caoutchouc have been discovered .’The process of vulcanization is often termed the sulphuring of

caoutchouc. Vulcani zation by calcium or sod ium hypochlorite or freehypochlorous acid , l ike vulcanization by holog ens (brom ine , iod ine , oriod ine brom ide ) , leads , as is known, only to “

horny rubber, i .e ., to ebonite- l ike substances . Compare Marckwald and Frank, “Uber H erkommen

und Chem ie des Kautschuks, Dresden, pag e 62.

TRIN I TROB ENZENE 277

When heated with unsaturated hydrocarbons, sulphur produces a twofold eff ect : it combines at the double bond withformation of thiozonides (E rdmann ) , or it oxidizes the ethylenegrouping, removing hydrogen in the form of hydrogen sulphide,a new ethylenic derivative, or a new compound containing sul

phur being thus formed .3O n the physical side, sulphur i s characterized besides by the

ordinary constants (specific gravity, melting point, and byits abil ity to exist in different polymorphic modifications (rhombic, hexagonal , amorphous ,

In searching for organic substances which vulcan ize caoutchouc , l ike sulphur, the first to be investigated are those whichresemble sulphur in oxidizing ethylenes , and at the same timeare able to unite at the double linking. O f the physical constantsof such substances the essential ones are the melting point andthe vapor pressure at the temperature o f vulcanization ; a fterthese, the solubil ity in caoutchouc, specific gravity, etc. Besidespossessing physical constants near to those of sulphur, the soughtfor compounds should exist in polymorphic modifications .

Th is explains why, in this investigation , I first of all made{halt at compounds containing the nitro-group. These oxidizeorganic substances (6 . g .,

in Skarup’s synthesi s o f quinoline) ,and at the same time readily combine with various ethylenes(attention may be called to the compounds of A r (NO 2 ) withpolycyclic hydrocarbons and to the author’s use of tetranitromethane as a reagent for double bonds ) .

1 3 5-Trinitrob enzene has melting point , 118 degrees C. ,

very near to that of sulphur, i .e.,below the temperature of vul

canization, and in specific gravity it also resembles sulphur.F urther, most polynitro- compounds exist in polymorphic mod ifications .

1 :3 :5-Trinitrobenzene was the first instance which I

hoped would serve as a substitute for sulphur in vulcanization .Experiment completely confirmed m ex tation. It was foundthat both synthetic and natural caoutchoucs are vulcanized morerapidly and easily by various nitro-compounds than by sulphuritsel f under the same conditions . The f esult was a product possessing all the associated physical properties of caoutchouc vulcanized by means of sulphur. Experiments were m

ade with both

aWhen acenaphthere is heated with sulphur, the hydrocarbon(decacy clene) is formed .

7

278 VULCAN IZA TI ON W'

I THOUT SULP HUR

fatty and aromatic nitro-compounds , and vulcanization tookplace with nitrobenzene , dinitrobenzenes , trinitrobenzenes , triand tetra-nitronaphthalenes , picric acid , picramic acid , picrylchloride, “artificial musk,” nitrocyclohexane , and many othercompounds .

F urther investigation showed that the vulcanizing propertiesof nitro-compounds do not depend on their capacity for combining at the double linking. A s is well known

,picric acid com

bines with ethylenic compounds considerably more readily thanmost other nitro- compounds of the aromatic series , and yieldsmore stable products . N ext in order come picryl chloride ,picramic acid , trinitrobenzene , etc . ; dinitro and mononitro-benzenes do not unite at all with ethylenic derivatives .

O n the other hand , according to thei r vulcanizing power,nitro- compounds are arranged in the reverse order, or moreaccurately, in an order which reveals no analogy between theprocesses of vulcanization and of combination at the doublelinking.Caoutchouc is vulcanized most rapidly and easily by 1 3 5

trinitrobenzene , after which come dinitrobenzene , mononitrobenzene, tetranitronaphthalene . P icric acid and picryl chloride donot yield satis factory products ; vulcanization undoubtedly begins , but, in spite of many seri es of experiments , I have neversucceeded in bringing it to completion ; the caoutchouc partiallyretains its plasticity

,and sticks when fresh f ractures are pressed

together. M ononitrobenzene , however, gives completely satistory results .4

The combining capacity of nitro- compounds increases withthe number of nitro-groups in the molecule , but we are convinced that the vulcanizing power of nitro- compounds does notdepend on this cause . O stromislensky found that tetranitromethane unites w ith ethylenic compounds o f both the aromaticand aliphatic series , but in no case has it been possible to vulcanize caoutchouc with tetranitromethane , although a large number of attempts have been made .

Various other substances which , l ike nitro- compounds , areable to unite with ethylenic derivatives , have also been tried ,‘

S l ight adhes ion between f reshly cut sur faces , as is wel l known,

does not ind icate that vulcanization is incomplete, espec ial ly with rubber

which has been only recently vulcanized .—H . P . S .

280 VULCA N I ZA TI ON WI THOUT SULP HUR

oxygen at the double linking of the caoutchouc. A ctual experiment gives the results expected, since barium peroxide producesno trace of vulcanization .

These new methods of vulcanizing caoutchouc , and thefavorable results obtained , are of undoubted scientific and praetical interest , and in the first place throw new light on the puzzling mechanism of this process .We are convinced that the present day vulcanization ofcaoutchouc begi ns with a chemical process . O nly certain classes

of substances— sulphur and some of , its derivatives (S 2 C1, ,Ca nitro-compounds , peroxides and per-acids— bring aboutvulcanization . The physical constants and pecul iarities of thevulcanizing substances are without influence on the final effect.What can there be common to the physical properties of. gaseousoxygen , sulphur, tetranitronaphthalene and perbenzoic acid ? A t

the same time it is sufficient to replace the oxygen of dinitrotriphenylmethane by hydrogen or to remove from the nitro-groupof nitro—benzene one atom of oxygen, to obtain a compounddiaminotriphenylmethane, nitrosobenzene— absolutely devoid ofthe power to vulcanize caoutchouc .

In the process of vulcanization , chemical reactions areallotted, therefore, a definite but still quite modest place. Chemical action with the vulcanizing compound occurs with only anegligible f raction of the initial caoutchouc. Thus , it is foundthat the complete vulcanization of 100 parts of natural P aracaoutchouc requi res only part of nitrobenzene or 1 :3 :5

trinitrobenzene .There can be no question here of molecular proportions,

since 100 parts of C H 1 6 would correspond with a minimum of156 parts of C6 H 3 Even i f it is assumed that C1 0 H 1 ,

requi res only one atom of active oxygen— which i s not trueand that the molecule of trinitrobenzene contains three atomsand that of nitrobenzene one atom O f active oxyg en , 100 parts ofcaoutchouc would requi re 52 parts o f t rinitrobenzene or 90 ofnitrobenzene . Even the corresponding sol id ebonite is , however,obtained by vulcanizing rubber in presence of 10- 15 per cent. oftrinitrobenzene .

Thus, with the actual methods for vulcanizing caoutchouconly a vanishing part o f the latter enters into chemical reaction ,

P HA SES OF VULCAN IZA TI ON 281

but this reaction is actually indispensable . The further course ofthis interesting process is conditioned by physical interactionbetween the vanishing quantity of caoutchouc which has reactedand that which has remained unchanged .

Thus, we arrive at the conclusion that the vulcanization ofcaoutchouc is divided sharply into two fundamental phases : (1)A chemi cal reaction affecting only an InS IgnIficant part of thecaoutchouc, and (2 ) adsorption or swelling of the unchangedcaoutchouc into the product of this chemical reaction .

Vulcanization may, however, be imagined as an exclusivelyphysical process, since theoretically it may begin with the secondphase of the process . Thus , instead of bringing nitro-compound ,sulphur, or peroxide into contact with caoutchouc, we may isolate and make use of the minute proportion of substance formedin our first phase ; by heating this mixture we should undoubtedly Obtain vulcanized caoutchouc . In such case vulcanizationtakes place in a single phase— adsorption or swelling of theinitial caoutchouc into the mixed product, and represents an exelusively physical process typical o f caoutchouc . In vulcanization by means of sulphur the existence of the latter in the freestate is of no importance, as it i s necessary only for the preliminary formation O i its compound with caoutchouc, and then onlyin negligible amount .7

The elastic and other properties of caoutchouc vulcanized , forinstance , by trinitrobenzene, are qualitatively and quantitativelyidentical with those of caoutchouc vulcanized with sulphnr . Bothsubstances are devoid of plasticity and stickiness and exhibitsimilar difficult solubility, etc .

O nly by chemical analysis might these two vulcanizates bedistinguished , although they are obtained by treatment of caoutchouc by absolutely different compounds . The nature of the vulcanizing substances is, therefore, almost without influence on thephysical properties , solubility and all the elastic properties of theresulting caoutchouc ; it has, further, no effect on the chemicalproperties of the vulcanizate , since the latter contains only anegligible proportion of foreign substance .

I t may again be emphasized that the characteri stic changes'I t may be that th is compound vulcanizes caoutchouc only when in

“s tatu nas cendi .

282 VULCAN IZA TI ON WI THOUT SULP HUR

in the properties of caoutchouc produced by vulcanization aredetermined exclusively by a physical process— the adsorption orswell ing” of the caoutchouc .

These new methods of vulcanizatIOn of caoutchouc open upa wide perspective , and it may be that the nitro- compounds , peroxides and per—acids represent only the “first swallow” and thatfurther work will reveal sooner or later other quite diverse substances capable of vulcanizing caoutchouc like sulphur.8

F urther investigation o f this method of vulcanization9 showsthat natural P ara caoutchouc is completely vulcanized by as littleas per cent. of trinitrobenzene , whereas 6 per cent . of sulphurwould be requi red . F urther, in the latter case , the Unavoidablepresence of free

,uncombined sulphur lowers the technical value

o f many rubber wares . The use of diff erent organic compoundsfor vulcanization of caoutchouc allows o f considerable variationin the physical properties , e. g .

,flexibil ity, elasticity , etc ., besides

in the color, smell , etc . Vulcanization may be eff ected by monodi and tri-nitrobenzenes , -toluenes , etc . , tri and tetra-nitronaphthy lamines , picramic acid , picryl chloride , artificial musk , nitrocyclohexane, nitro-dyestuff s , etc . M etallic oxides , Which facilitate the vulcanization of rubber by sulphur and enhance the valueof the product obtained , exert a similar eff ect on vulcanization bynitro-derivatives . Lead oxide is most valuable in this respect, andthen follow, in order, oxides of zinc , calcium, magnesium , barium.

O n the other hand , mixtures o f aliphatic amines with the aboveoxides , although they accelerate vulcanization by sulphur orlower the temperature o f the process by 10 to 15 degrees C. ,

retard vulcanization by nitro-compounds and lower the value o fthe corresponding product . Like sulphur and sulphur chloride ,nitro-derivatives vulcanize , not only caoutchouc , but also variousvegetable oils yielding products analogous to factice .

The vulcanization of caoutchouc by means of peroxides proceeds considerably more rapidly and at a lower temperature thanvulcanization by means of sulphur or even nitro- compounds .

3I t m ight be expected on theoretical g rounds that caoutchouc would

be vulcanized under su1table cond itIOnS by oxides of nitrog en, hyd rog enperoxide, ozone, ozonides of the terpenes , oxyg en or air in presence of

compounds Wt h activate oxyg en, and many other substances .

9 From the“

Journal of the Russian P hys ico-Chem ical Soc iety , 1915,pag es A bstract f rom “

Journal of Soc iety of Chem ical Industry , Vol . XXXV, p. 59.

284 VULCAN I ZA TI ON WI THOUT SULP HUR

develop on their surface soft , colorless , crystalline leaflets , whichare as transparent as glass , and possess pronounced lustre ; afterthe lapse of a longer time (1, 3 or 5 months ) the vulcanizate begins to oxidize and gradually becomes sticky ; finally it runs ,becoming converted into a sticky, more or less viscous, plasticmass .1 2 The vulcanizate decomposes especially rapidly when inContact with the original , non-vulcanized mixture, which evidently acts as a “detonator.”Consequently, when diff erent mixtures of caoutchouc andbenzoyl peroxide are either heated or stored , two processes takeplace simultaneously : (l ) Vulcanization of the original caoutchouc, this being connected with partial or complete union of theoxygen of the peroxide with the caoutchouc , and (2 ) oxidationof the caoutchouc by the benzoyl peroxide with formation ofthe highly sticky mass mentioned above .

The relative rates o f these two processes determine the effectof the vulcanization , and experiment shows that these rates depend on the proportion of benzoyl peroxide , on the temperature,on the prolongation of the vulcanization , and on the nature andquantities of the foreign matters in the initial mixture .

Vulcanization of caoutchouc with benzoyl peroxide requires ,therefore, increased attention or skill in the operator.When Once started at a high temperature , the process of vul

canization continues comparatively rapid, even at the ordinarytemperature . Thus , it was found that a mixture of normale rythrene caoutchouc and a small excess of benzoyl peroxideconverted after 27 days into a very sticky, viscous mass , whichlater gradually runs or assumes the form of the containing vessel . When previously heated

,without access of air

,two minutes

at 85 degrees '

C., the same mixture does not run when keptat the ordinary temperature ; '

ou the other hand,the stickiness

already present disappears spontaneously ; the plasticity of freshsections and their proneness to become sticky are lost , and themixture gradually vulcanizes at the ordinary temperature, andfinally even over-vulcanizes , owing to the excess of benzoylperoxide present.

0

”Some caoutchoucs

,for instance, normal erythrene caoutchouc

,vul

cani zed with a larg e amount of benzoyl peroxide, g radual ly sol id i fy whenkept, y ield ing a dense, br ittle mass, eas i ly powdered but absolutely without sti ckiness.

OX IDA TI ON AND VULCAN IZA TI ON 285

I t i s seen that the relative velocity of oxidation , on the onehand , and of vulcanization on the other, depend on the character of the preliminary treatment , in the given case on the twominutes’ heating at 85 degrees C .

This fact explains immediately Why incomplete vulcan i zation protects caoutchouc from oxidation or decomposition in theai r.

The benzoyl peroxide may be replaced by perbenzoic acid ,and probably by ozone, ozonides of caoutchouc or terpenes, nitrogen , oxides , ce rtain metallic peroxides and hydrogen 'peroxide.F urther, my observations show that barium peroxide produces no trace of vulcanization in caoutchouc . I nto natural P aracaoutchouc were introduced 1 per cent ., 5 per cent ., 10 per cent .,

15 per cent. and 50 per cent. B aO z, the mixtures being vulcanizedfor 5 minutes , 10 minutes , 30 minutes , and 2 hours with steamat 2 , 3 and 4 atmospheres pressure in a press ; under these conditions the mixture underwent no change , its plasticity and evenits light color remaining quite unaltered . This interesting ob

se rvation lends further confirmation to the fact that vulcanizationo f caoutchouc by the above method takes place at the expense,not of the peroxides themselves, but of their active oxygen .

The accompanying table contains recipes for the vulcanization o f diff erent caoutchoucs with benzoyl peroxide . I t mustbe pointed out, however, that the external conditions indicatedin this table are by no means ideal .1 3

To conclude, in presence of -3 per cent. of benzoyl peroxide , normal " synthetic caoutchouc, Obtained on coagulation of itssolution , undergoes at about 80 to 120 degrees C . incomplete vulcanization. The exte rnal appearance , and all the new propertiesof the product Obtained , compel the assumption that some formsof natural rubber represent products of incomplete (incipient )vulcanization caused by active oxygen .1 4

Very recently a United S tates patent has beengranted to Dr . O stromislensky for a new process of vulcanizationand the product resulting. The process is an interesting one ,since it eliminates the time-honored use o f sulphur for vulcani

1’The detai led rec ipes for the vulcanization of caoutchouc by means

o f benzoyl peroxide, tog ether with other documents kept in my pocketbook, were unfor tunately stolen from me.

O r by compounds containing active oxyg en, etc.

286 VULCAN IZA TI ON WI THOUT S ULP HUR

zation and may possibly indicate a distinct advance in the develOpment of the industry .

To quote from the patent specification , the process is described essentially as follows

The invention consists in treating a mass of rubber withhalogen or halogen-acid compounds of natural and synthetic rubber

,such as rubber chlorides and hydrochlorides , chlorides and

bromides of the synthetic rubbers . These substances may beprepared by the direct action of halogens or halogen acids onsolutions of rubber. The halogen compound , chloride or bromide of rubber, i s first reduced to a fine powder and then combined with the rubber on the mixing rolls . The proportions employed are 10 grams of rubber and 7 grams of dimethylerythrene rubber bromide . The material i s placed in the vulcanizing press and heated for one and a hal f hours at 130 degrees C . The product is an ebonite—l ike mass .

A S alte rnative procedure, 10 grams of rubber, 85 grams ofnatural rubber bromide heated at 130 degrees C . for two hours ,produced a similar ebonite- l ike material . Seven grams of rubber heated with 10 grams of cauprene bromide at 130 degreesC. for two hours gave a similar result . Three- tenths gram ofrubber, heated with grams of cauprene chloride at 130 degreesC . for two hours and twenty minutes , gave an ebonite- like massonly superficially colored black .

The substances thus obtained are similar in color to ordinaryebonites , and possess equal stabil ity and physical properties .They do not conduct electricity, may be easily cut and polishedand retain the luster even in damp air.

Soft rubber may be produced by vulcanization with hydrochlorides of natural rubber. The preferred proportions givenare one part of natural rubber heated with 16% parts o f hydrochloride of natural rubber at 130 degrees C . for two hours . Theresulting soft rubber is generally applicable where soft rubbersproduced by sulphur vulcanization have been used .

A Similar form of vulcanization takes place when unvulcanized rubber i s subj ected to the action of an ozonide of rubber.

This ozonide may be prepared by subj ecting layers O f rubberf rom one-hal f to one mi llimeter in thickness to the action of astream Of dried air under the influence of the rays of a mercury

0 “

VULCAN IZA TI ON WI THOUT SULP HUR288

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CHA P TER XVl l .

RECLA IMED RUB B ER A ND ITS USES .

TH E industry of reclaiming rubber f rom vulcanized wasterubber articles developed from experimental beginnings as anecessary adjunct of the manufacture of rubber goods .Reclaimed rubber has risen in estimation and increased in importance , until its output has attained an annual tonnage equaling about hal f that of the world’s tota l production of crude rubber for the same period . I t i s thus a very important division ofthe rubber industry and a marked economic factor in it s development. The growth of the rubberreclaiming trade naturallytends to eliminate the smal l factory reclaiming plant, because ofthe more eff ective - economies and the better standardization ofproduct possible under the conditions of operation that obtainwith companies o f large capital , world-wide connections andspecialized effort . Such rec laiming companies employ specialmach inery

,and maintain research and analytic laboratories for

control of thei r proc esses , standardization of products and studyof reclaiming and compounding problems .

Reclaimed rubber, known also as regenerated and' devulcanized rubber

,can be compounded , manufactured and vulcanized

a fter the manner of crude rubber. The better grades are avai lable as compounding material for quality as well as economy .The lower grades afford inexpensive and useful compounds formany mechanica l goods , molded articles and proofed fabrics .

The following figures will give a rough idea of the amounto f reclaimed stock produced annual ly in the United States andthe sources from which derived .

Sour ce s

Boots and shoes

A utomob i le ti r esM echanical s and sund r iesI nner tubes

Sol id truck tir es

Total United States production

292 RECLA IMED RUBB ERit is apt to be very hard . A t one time hardrubber dust was tobe found in the market and was used as a shoddy in certaingrades of vulcanite . There is to—day but very little of it to befound , however, as most of the manufacturers of hard- rubbergood s find a use for all that they make .

The processes followed in the reclaiming of waste rubberare no longer secret. Those who are in the business of manufactur ing for the trade are able to do it , as a rule, because theybuy waste stock at a lower figure than a small user could , besides which , by manufacturing the goods in large quantities ,they can do it more economically and maintain higher averagegrades than it could be done in a small way .

In this business are used crackers , sheeting mills like ordinary grinders , and , indeed , general machinery not dissimilar tothat used in a mi ll where crude rubber is compounded . Theyhave in addition , however, lead- l ined tanks for acid treatment ,vulcanizers or, better, devulcanizers , huge vats for washing,magnets for removing metal , sieves , and drying facil ities . Thisbranch of the rubber business is not supposed to be deeply interested in compounding, in spite of the fact that it i s sometimessuggested that earthy matters , heavy adulterants , and oils do finda use in reclaiming mills .

Rubbe r scrap of any sort, vulcanized or unvulcanized , isactively sought for reclaiming the world over. The larger factories use their own scrap o f both kinds, yet much unvulcanizedscrap gets upon the market

,chiefly in the form of P ara cable

strippings , mackintosh cloth cuttings, frictioned fabric , andcement ball .

Next to this in value , and indeed often more valuable , i s thepure gum vulcanized scrap, such as rubber thread , and a varietyof floating stocks that do not contain rubber substitutes . Specialhigh-grade stocks , such as inner tubes , billiard cushions , balloonfabrics , etc ., are favorites in this line .

A utomobile tires constitute the largest single item in scrapcollection . Ten years ago old rubber boots and shoes occupiedthis position , and now rank second . O ld rubber boots and shoesare graded roughly by the country of their orig in— American ,English , German , Russian and so on— and their conversion into

P RO CESSES 293

workable rubber has long been the backbone of the reclaimingbusiness .

M ost of the products of the mechanical goods factory comeinto the market as waste eventually, and are sorted and gradedaccording to the richness of the compound , and the freedom frommetal and fabric . In this line is the red scrap , such as valves ; thedrab , emb racing wringer rolls , mattings , buffers and hose , gradedas air brake, fire-hose linings and garden hose . Then there isthe grading of belting, asbestos scrap , red and other packing.

In tires there is the collection and sorting of'solid tires intocab, baby carriage and truck tires . In pneumatics

,there are

single and double tube b icycle tires , motor cycle casing and automobile ti re shoes— American , F rench , and German . There isalso the inner tube in gray, red , and black that i s to-day a largefactor in the recovery business .

In druggists’ sundries , water bottles and the like furnishwhite and red rubber, while air and water beds , sponges andmany other specialties furnish regula r grades .

In hard rubber, cells , telephone receivers , sheets and rodsare ground up and used again , while hardrubber shavings anddust find a ready market .

Gutta-percha , in the form of .cable strippings , balls and

buckets , is a type of waste with a recognized place .A nd these are but a few of the many grades put out by thesorters , and sold to the scores o f reclaiming plants the world

over,that produce tons of usable rubber from what was once

thrown away‘

or burned under the factory boilers .A lmost the first attempt at recovering rubber waste was that

done at the B everly Rubber Works , in Massachusetts, back in thefi fties , when H i ram “

L. Hall boiled waste vulcanized rubber inwater, after reducing it to a powder, and then sheeted it. I t i sa curious fact that , in one little mill to-day, the manufacturergrinds his own scrap , boils it in hot water until it is in conditionto sheet, and makes a fai r article out of it.

The year a fter Hall’s patent , another was granted to F rancisB aschnagel , who paved the way for devulcanization by coveringa process whereby a finely 'ground ‘ rubber was exposed to theaction of live steam . It was not , however, until E . H . Clapptook hold of the business and discovered a process for i

b lowing

294 RE CLA IMED RUB B ERthe fiber out of the finely ground rubber prior to its devulcanization that the goods began to be used to a large extent .

The next step in the progress of the art was characterized bythe taking out of a great variety of patents , most o f which dependupon various acids and alkalies for destroying the fiber. Thesepatents were more than fi fty in number, and were ful ly reviewedwith their attendant processes in the famous suits brought by theChemica l Rubber Co . against The Goodyear’s M etallic RubberShoe Co . and the Raymond Rubber Co . While it would betedious to go into that matter, it i s interesting to touch upon important processes involved . The action of acids upon fibers

, of

course, had long been known ; in connection with the rubber business , however, it was without doubt novel . The Hayward patent ,for instance , mixed 75 pounds of sulphuric acid with 8 hogsheads of water, and in this way the fiber was weakened so thatit was easi ly ground up with the rubber. The F aure patent calledsimply for the immersion of the clippings in an acid , which indisintegrating the textile matter set the india rubber free . H iramHall advised the use of lime or alum to eat Up the cloth , and alsoa solution of 1 part of sulphuric acid to 9 parts of water. B urghardt used muriatic acid for destroy ing '

the cloth fiber. The

Heinzerling patent ca l led for a treatment first with acids,and

then with alkalies . I t i s also to be remembered that CharlesGoodyear directed that crude india rubber should be subj ectedto a 10 per cent . solution of sulphuric acid to eat up the bark withwhich the gum might be contaminated .

The M itchell patents , the B ourn patents , and others , wherean extremely dilute acid was used , and where a concentratedacid was called for, have been so thoroughly reviewed that thosefamiliar with the rubber business know all about the processesemployed .What i s known as the alka l i process , based upon the patents

of A rthur Hudson Marks , is one of the notable improvements inrec laimed rubber in more recent years . F actories for reclaimingunder this process are operated in the United S tates , England ,Germany and B elgium , mechanical waste being chiefly used .

In addition to the processes in more general use , a fewunusual ones _may be interesting. F or example , the Torstrickprocess

,in which dilute nitric acid and fusel oil were mixed with

296 RE CLA IMED RUB B ERB asle process . A Swiss process Which covers the use of

various ethers boi l ing at a temperature o f about 100 degrees C .B rimmer’s process (German ) consists of mixing ground

scrap with castor oil , heating until dissolved , adding alcohol forprecipitation and washing with a weak solution of caustic soda .Cl i ft’s process (Engli sh ) . Waste rubber is dissolved in a

base of the pyridin group , treated with acid in the presence of avolatile solvent for the separation of the rubber f rom the base

,then the solvent separated , leaving with the rubber in solution .The Chautard process (F rench ) uses commercial phenol forreclaiming, the phenol being later distilled off . The whole process

is quite intricate .The Durvez process (B elgian ) . Rubber waste boiled with

water and finely powdered lime . P roduct is washed , rolled , anddried .

Eves’

s process (American ) . Devulcanizing by treating withsodium sulphate in the presence of heat , then incorporatingbarium chloride .

F rench process . Waste vulcanized rubber is heated withterpin hydrate , the mixture is then treated with bo iling water,and f rom the residue the regenerated caoutchouc is extracted bymeans of a suitable solvent , such as commercial xylol . The terpinhydrate is recovered for use over again by cooling the hot aqueous wash- liquors .

F rench process . The finely divided rubber is heated , pre fe rably at 110 degrees to 180 degrees C. , under pressure , with asoap solution , to which may be added other substances , such asaliphatic or aromatic hydrocarbons , oil o f turpentine or the like ,and salts capable of forming solutions which dissolve sulphur,such as alkali sulphides , alkali sulphites , etc .

Gilbert-B esaw process (American ) . This process is notpatented

, but i s secret . I t is applicable to the recovery of any sortof rubbe r scrap,whether cured in open steam, in molds , or indry heat . A ccording to the statement o f the inventors no acidor alkali

,or anything that can be in any way injurious , I S added .

The machinery for treating the waste rubber for the removal offiber and for devulcanization is individual to the process . The

time occupied in devulcanization is about one-quarter that used

P RO CESSES 297

in existing processes . No residuum or oily matter of any sortis added to the product , either be fore or after devulcanization .

Gregory and Thom’s process (English ) . Reclaimed in theusual way ; then a solvent is added which is a mixture of anilineoil and naphtha . The product is heated in open steam until thesolution of rubber is complete , when it is taken out and strained

Gubbin’s process (English ) . Unvulcanized scrap in whichthe fabric is saturated with naphtha and passed through plainpressure rolls to remove the rubber from the fabric .

H einzerling’s process (German ) . Ground waste rubber

treated with aniline or its homologues at 140 degrees to 180 degrees C. The rubber is then mechanically separated from theresidue ; is treated with dilute sulphuric acid , and the separatingrubber is washed and dried .Heyl-Dia’s process . Heats ground r ubber under moderate

pressure in naphtha , temperature being not more than 120 degrees F . The naphtha is then drawn off and with it most of thesulphur. The rubber is then heated to over 350 degrees F ., witha fresh solvent when it dissolves . The solvent is then removedand the sulphur washed and dried .Hyatt and P enn’s process . Waste rubber finely ground is

put into a vacuum chamber and molded into goods under heat.Ka ravod ine

’s process (F rench ) consists of pulverizing thematerial , adding asbestos fibers which have been previously

treated with a binding medium , and subj ecting the mass to ah igher pressure at higher temperature .

Kessler’s proc ess . Waste rubbe r is treated with carbolicacid in a vacuum . A fter solution powdered acetate of lead isadded and the whole submitted to distillation . Caustic soda isused later for neutralizing.

Kittel’s compound (A ustrian ) . P owdered waste mixed withcaustic alkal ies is compressed into cakes and heated 2 or 3 hoursat 280 degrees C .

Koneman’s process (American ) . Ground waste is boiled

in a salted-acid solution , and a mixable fixed hydrocarbon is thenadded .

Koener’s process (German ) . Waste rubber is heated with

solvents , such as benzine , for a time , after which the solution isfurther heated with water and solvent subsequently disti lled off .

298 RECLA IMED RUB B ER

Marks’

s process (American ) . Waste rubber finely groundis heated in a dilute alkaline solution in a closed . vessel for ‘

a

time and at a temperature dependent upon the amount of sulphurpresent .

Murphy’s process (American ) uses for devulcaniz ing a bathconsisting of carbonate of soda and gallic acid .N eilson’s process (German ) . The inventor uses resin oil

as a solvent,

fi lters and precipitates the r ubber by means o f aketone .

P assmore’

s process dissolves vulcanized waste with eucalyptol and removes mineral matters by filtrating . The eucalyptol isdriven off by hav ing steam forced through the mass .

P enther’s process (German ) . A devulcaniz ing machine o f

German origin makes what is known as American reclaimed rubber. I t separates the fiber from the rubber so thoroughly thatthe fluff i s a merchantable product in the felt trade .

P eterson’s process (American ) consists in subj ectingshredded waste to an alkaline solution raised to a boiling temperature under hydraul ic pressure , next washing in water solution containing phenol under a high temperature and pressure .

P rice’s process (American ) uses caustic solutions o f markedstrength , under ordinary atmospheric pressure .P rice’s process (English ) . A process whereby waste rubber

cut into pieces of suitable size is roughly mixed with crude rubber and ground fl int and without being vulcanized , by great pressure molded into fin i shed goods .

Roux process (F rench ) . The inventor describes a machinewhich devulcanizes powdered waste rubber and makes it intotubing at the same time . In other words it is a combination ofa devulcanizer and tubing machine .

Steenstrup’

s process . The waste is heated in a solution ofa lkal i and hydrofluoric acid under steam . The product is thenwashed , dried , etc .

Theilgaard’s process (Denmark ) . The inventor has several

patents which cover the treatment of vulcanized scrap by alkaline earths and such solvents as sod ium sulphide .Wheeler’s process (American ) consists in subj ecting thewaste particles individually to a current o f heated fluid moving

through a confined passage .

300 RECLA IMED RUB B ER

0true solution of the problem of eff ecting a real devulcanizationof vulcanized rubber must lie in the use of a powerful vulcanizing accelerator in conjunction with an element capable of combining with and fixing the sulphur liberated from the rubber bythe accelerator . The more powerful the accelerator the moremarked should be the results obtained by the means of it, andthis principle should govern the choice of the accelerator employed . Theoretically, all that i s necessary is a powerful accelerator and an element or substance to combine with the sulphurset free by the accelerator. The presence of this latter substanceeven will be unnecessary i f the accelerator itsel f i s employed inexcess and is capable of form ing a stable derivative with the sulphur under the temperature and other conditions o f the experiment . The principle has been tested by experiments

,and it has

been found to form the basis of a success ful desulphurization ofvulcanized rubber, Spence having succeeded in eff ecting the removal of large proportions o f the combined sulphur from vul

canized india rubbe r by the use of several of the most powerfulo f those reagents , which are known as “catalysts ,” or moreusually “accelerators ,” employed in vulcanization . A solution ofaniline—potassium or of aniline- sodium in excess o f aniline whichi s formed by the action o f dry aniline on metall ic potassium , orsodium can be used very effectively in removing combined sulphur from vulcanized rubber ; this solution in addition to itsaccelerant action actually serves as a means o f fixing the sulphur liberated from the rubbe r as an insoluble metallic sulphide .A s an example of a powerful organic accelerator, which is veryeffective in removing combined sulphur, piperidin may be mentioned . Caustic soda— long since shown to be one o f the mostpowerful o f inorganic catalysts— i s another suitable substancefor eff ecting removal o f combined sulphur of vulcanized indiarubber. This substance has the advantage of being cheap .

Generally speaking, Spence has found that it i s best to workwith all components o f the reaction in solution ; and in this connection the use o f a solution of aniline-potassium in excess o faniline sufficient to dissolve the rubber at the Operating temperature is particularly advantageous . In this case , the rubber, aswell as the accelerator , i s brought into intimate contact in aniline solution

,and the sulphur which is liberated is thrown out

P RO CES S ES 30 1

o f the field of reaction as an insoluble alkaline sulphide . In thecase where caustic soda is employed as the devulcanizing agent ,the less complete devulcanization eff ected is explained by thefact that no solvent or means has yet been found of bringingthis accelerator and the rubber together in homogeneous solution. Vigorous ag itation facilitates the reaction . S imilarly, theprocess , in order to eff ect the best results , should be carried outin absence of moisture , the presence o f water having been foundto be particularly disadvantageous. The temperature at which thereaction may be carried out may vary within wide limits according to the reagent used ; the higher the temperature , within certain limits

,the better will be the results obtained , and for practical purposes it is found that a temperature of about 170 to

180 degrees C. is usually advantageous .A s examples of the eff ectiveness of his process , Spence citesexamples o f the reduction of the combined sulphur from 78 to

90 per cent . in one Operation in soft vulcanized rubber and 73per cent . in hard rubber.

CHA P TER XVl l l .

P HY S ICA L TE STS A ND A NA LY SE S O F CRUDE A ND

VULCA N IZED RUB B ER . S P EC I F I C GRA V ITY .

S P EC I F I CATIO NS F O R TE STING RUB B ER

GO ODS .

IT long has been the boast o f expert rubbe r superintendentsand manufacturers that they find little trouble in matching compounds . A s a matte r of fact, some of them are remarkablyexpert. Given a small samp le of vulcanized rubber in a familiarl ine and the price at which it must be produced , they are oftenable, without much experimenting, by thei r knowledge of rubber and compounding ingredients , to get a result apparentlysimilar.

This , in fact, was the only way possible when rubber manufacturers Operated on individual knowledge and experience andin sel f-defense conducted thei r processes secretly and withoutscientific assistance . Under modern conditions it is no longeradvisable , even for experienced superintendents, to attempt closeduplication O f particular rubber compositions or to meet specified requi rements by inspection for Odor, color, weight or qualitative hand tests o f strength , stretch and hardness .

Rubbe r manufacturers are no longer credited by importantcustomers with exact knowledge o f what will best serve the needsof the latter ; hence specific specifications , the laboratory, thedevelopment department, and the introduction of team-work inthe coOrd ination of science and practical experience on the partof chemi st, superintendent , and heads of factory departments .

To meet these conditions , the rubber manufacturer requiresintimate knowledge concerning the origin and preparation of

market grades of crude rubber and methods for determiningtheir quality.

S tandardization of regular factory product , including considerations O f quality as well as price , calls for application ofthe scientific method .

304 A NA LYSES O F RUB B ER

in an empiri c way by the producers and their conclusions reserved and compared after completion of the sc ientific tests madewithout knowledge of the first results .A N A B STRA CT or TH E SCI ENTI F I C METHOD A ND F OL’S CON CLUS I ON S .

Empiric judging of rubbe r depends largely on color, smell ,and stretch . These tests at best are only roughly approximate ,

although the rubber expert by means O f them can distinguishmarked diff erences in quality. I t is a mistake to presuppose thatmechanical properties o f the rubber when vulcanized run parallelto color, smell and stretch in the raw state. Variations in physical condition do not permit hand-pulled tests nor quantitativeexpression of value . The influence of temperature variationsis also marked.

Smoked sheet cannot be judged better by rule of thumb thancrepe . I ts color denotes only the degree of smoking. Sheet iseasier judged as to its mechanical properties than crepe .

B lack rubber presents the most diffi culties for empiric judgment , as it cannot be subj ected to a hand test .

Scientific methods obviate these obj ections , because eachsample i s suitably prepared and tested quantitatively. The 137

samples under investigation were examined after the followingscheme :Chemical A nalysis1. M oisture .2 . Resin.3 . A sh .

4. N itrogen calculated as albumen .5. Rubber.6. A cetic degree .Vi scosity Number.Vulcanization and P hysical Tests1. Tensile strength .

2. E longation .3 . P ermanent set a fter 24 hours at 400 pe r cent .stretch measured after six hours’ rest.4. Temporary set measured directly after release f rom

40 ) per cent . stretch .5. Determination of load necessary to stretch sample

'

4(I ) per cent . (kilograms per square centimeter) .

CHEM I CA L AND P HYS I CA L P RO P ERTI ES 305

C . Vulcanization and P hysical Tests (Continued ) :6 . Diff erence of the load necessary to stretch sample

400 per cent . and that requi red for the last o ffive successive 400 per cent . stretchings .7. E lasticity or rebound .8. Coefficient O f vulcanization .

Concerning the importance and corre lation O f these determinations , F ol concludes : (1) chemical analysis is not sufficienta lone for judgment of the rubber quality . P roperties O f rubberare chiefly determined by the physical nature o f rubber and therubber molecule . The quantitative chemical diff erences are notenough to account for the large differences found in the physicalproperties ; (2 ) in general a high viscosity indicates good mechanical properties of the rubber after vulcanization . However

,the

opposite must be assumed with some reservation , since in studying the relation between the viscosity and tensile strength itappeared that various samples with a low viscosity had a veryh igh tensile strength . The samples that exhib ited this relationwere almost exclusively smoked sheet . This phenomenon iscaused by the fact that it is very difficult to dissolve smoked sheetin benzol completely . The dissolved part has a low viscosityand presumably contributes little to the excellent qualities shownby the sample after vulcanization , whi le the very considerableamount of undissolved rubber apparently is the most valuablepart of the sample and most probably causes the good propertiesa fte r vulcanization .

The tensi l e strength ,permanent set after stretching 400

per cent . and the coefficient of vulcaniz ation were taken asquantit ies suitab l e for clas s ify ing the samp l es . These quanti ti es are c lose l y related . Thus . h igh tensi l e strength generally accompanies h i gh coefficient of vu lcanization and lowpermanent s‘et . E longation at b reak a l so indicates the qua l ityof the rubb er : of samp l es equa l l y loaded , that i s the bestwh ich has the h ighest elongation at b reak .

The remainder of the phy s ica l tests made were set asideas practica l l y va lueles s for the end in v iew .

O ne

i

of the most important points demonstrated by th i si nvestigation is the lack of uni form i ty in firs t latex rubb er .The greates t divergencies were found in v i scos it y

,tens i le


strength,permanent set and the coefficient of vulcanization .

The causes o f th i s lack of uni formity and its prevention areamong the most important prob lems of the rubber industry.

The rubb ers investigated were clas sified as follows :Breaking strain Coe fficient of

(kilograms per sq . c . m .) Permanent set.

135 k. g . and over Maximum 5% M inimum 5120 k. g . to 135 k. g . 5% to 7% M inimum 4

90 k. g . to 120 k. g . 7% to 12% M inimum 3

80 k. g . to 90 k. g . Over 12% Below 3Below 80 k. g . O ver 12% Below 3

The div i s ion O f the 137 samples among the diff erentclas ses i s indicated b elow

Class . Shee t. Crepe . Blanket.17

2

3 012 21 37 51 2

0 11 10 9 0

36 9S 6

These figure s demonstrate c learly that,in genera l ,

smoked sheet i s b etter than crepe . However,there are sam

p les of crepe that are equal to smoked sheet as far as mechanica l propert ies are concerned . The number of samples ofblanket is too small to permit a decisive conclusion , but thefigure s would indicate that b lanket i s inferior in quali ty tosmoked sheet and often also to crepe .

Lack of uniformity in plantat ion rubbers reveals itse lfch i efly in the diff erence in rapidity of vulcanization . Two

rubb ers outward l y of ab solutely equal value may produce enti t e l y diff erent resul ts after vulcanization . Empiric judgmentcannot tel l how a rubb er wil l behave during vulcanization ,hence the estimate of value i s l iab le to be incorrect . Th i scaus es much uncertainty and di sappointment to the manufacturer .

The researches of K . Gorter on the v i scos ity index ' as astandard for the prel iminary testing of crude rubber are abs tracted as fol lows :3

The viscosi ty index i s the logarithm of the vi scosi ty ofa 1 per cent . solution and 'i s superior as a standard to the vi s

2O ne sample unsmoked .

" “Chem ical A bstracts ,” O ctober 10, 1916.


I f the difficul t ie s associated with the chem ical inves t igation of the nature and influence of the impuritie s” necessarilymake progres s in th i s direction s low ,

i t i s not surpri sing thatthe work having as its ob j ect the identification and evaluationby chem ical means of diff erent rubb er sub stances or caoutchouc s i s st i l l in a more or les s emb ryonic state .

Recent work by Caspari Suggests the poss ib i l i ty of discrim inat ing,up to a point , by physico - chem ical methods , between caoutchoucs of different commercia l quality . A ccord

ing to Caspari , rubb er i s of a composite character and consi sts of (l ) “ solub le” rubb er, wh ich i s a weak but elasticco l loid

,so lub l e in light petroleum ,

and (2 ) of “ insolub l e” or“pectous” rubb er , which i s an elastic colloid of considerabl emechanical strength . The latter , in some respects resemblinga sl ightl y vulcanized material

,preserves it s structure on con

tact with so l vents . I t i s,however

,gradually disso l ved by

b enzene and carbon tetrach loride , but whereas the v i scosit i esof the so lub l e in B razi l ian and plantati on P ara , respectively ,are very s imi lar

,the “pectous” in the latter i s far more readi ly

attacked by b enzene or carbon tetrachloride than the “pectous”of the former. A ccording to Caspari , B razi l ian fine contains35 to 50 per cent . of

“pectous,

” whereas p lantation rubberexam ined by h im showed no more than 10 to 25 per cent .Caspari be l i eves that “nerve” or strength i s main l y due tothe pectous” variety . The work of Caspari wil l requi re confirmation and amplification b efore it i s app l i ed to rubb ereva luation . I t suggests a new field of research , indicatingthe possib i l i ty of estimating the qual ity by a direct physicochem ical method .

SECO NDARY P RODUCTS— RUBBER RES I N S .

— The outstandingfeature of the work o f H e inr ichsen and Marcusson i s that al lresins

,excepting that f rom P ara (Hevea ) , are Optically active.

In certain cases , therefore , the absence O f optical activity in theextracted resin may be taken as evidence that no rubber otherthan Hevea i s present . P ara resin contains 15 per cent . andother resins up to 100 per cent . of unsaponifiable matter. The

opti ca l activ i ty appears to be mainly due to the latter . I odinevalues vary ing from for j elutong resin to 118 for P araresin were found . So far as the investigation has been carried

M ETHODS O F TEST 309

it appears that the resins from vulcanized rubber exhibit thesame characteristics as those from the crude material . D. B loom,

as the result of the examination of 150 samples of resin fromdiff erent species , concluded that the “acid value” of the resinfrom the same species is constant .

The eff ect of rubber resin on vulcaniz ing capacity is a matterO f controversy. Litharg e has been shown to be practically inoperative as a catalyst in the absence O f rubber resins . Wherelitharge or other catalyst was not emp loyed it has been foundthat the rubber resins do not exercise any marked effect on thecuring capacity .

M ECHAN I CAL I M P URI TI E s .

— B eadle and S tevens give the following method (for these materials only ) . They depolymer

ize”the rubber by heating with a solvent of high bo'il ing point ,

thinning sti l l further with a solvent of low viscosity,

filteringand weigh ing.

I N SOLUBLE M A TTERm N I TROGEN OUS SUBSTAN CES — This itemdoes not apply to accidental mechanical impurities , but to naturaland norma l substances always present to some extent in cruderubber . Whi l e there i s no proof that norma l “ insolub l e” i sessentially a nitrogen product (a part doubtless consisting ofoxidation products ) it is fairly certain that it normally containsa high proportion of nitrogen .

Schmitz’s,method , grams rubber, treated with 50 c c .

pentachlorethane for five to seven hours at 85 to , 90 degrees C .

with the formation of very fluid solution readily filterable , particularly i f somewhat diluted with chloro form . The residue canbe further purified by dissolving in five per cent . solution ofsodium hydroxide and reprecipitating with hydrochloric acid .

P RACTI CAL CO N S IDERATI O N S — There l s considerable evidenceto warrant the assumption that the “ inso luble” matter in cruderubber has an important bearing on vulcanizing capacity, but noquantitative relation has been discovered . While it has beenshown that the removal of the “ insoluble markedly decreasescuring capacity, the experience of the author is that rubbers withlow proportions of “ insoluble” do not necessarily cure badly, nordo samples with h igh “ insoluble” necessarily cure rapidly . P rob

3 10 . A NA LYSES O F RUB B ER

ab ly insoluble varies so in composition that further methods ofseparation must be devised before “ insoluble” can be taken as acriterion of quality. The author prefers the indirect method fordetermining “ insoluble , which consists in evaporating a convenient volume of clear solution , Obtained by treating to onegram of rubbe r with 100 to 200 cc . benzene in a tall cylinder,allowing to settle and weighing the residue in a pipetted portiondrawn O ff from above the residue .

E STI MATI ON O F RUBBER— A ssumi ng a satis factory method ofseparating the “ insoluble” matter, the most satis factory indi rectmethod of estimating rubber is by deducting the sum O f moistureplus resin plus “ insoluble” from 100. This method involves theassumption that the whole o f the ash and nitrogen i s present ininsoluble form . The author recommends the return of theanalysis in the following form

MoistureResin (acetone extract )Insoluble matterRubber (diff erence )The above contains

A sh (mineral matter )N itrogenN itrogen protein

These notes apply only to routine technical analysi s of whichthe chie f Obj ect is to ascertain whether a distinct abnormality isdisclosed and to control methods o f production or of gaugingsuitabil ity for specific manufacturing purposes .

DI RECT M ETHOD B Y TETRABROM IDE F OR DETERM I N I NG RUBB ER.

-The reader is re ferred for details of this method to the workby Caspari on “

Laboratory M ethods for Rubber A nalysis .”The reaction of bromine on caoutchouc is C1 0 H 1 6 6 B r

C H 1 4 B r4 2 H B r .

E STI MATI ON O F MO I STURE .—The best method is (l ) to dry inwater oven at 98 degrees C . till an increase in weight becomes

apparent or for a standard time of two hours , or (2 ) to takethe diff erence between original weight o f sample and weightafter acetone extract plus the extract .

3 12 A NA LYSES O F RUB B ER

tain intrinsic and typical properties of the raw material , such ascuring capacity, strength , distensibil ity and capacity for recover

A ny system of eva luation based on factors influencing thevulcanization process must be carried out under standardizedconditions o f mixture , cure and test . P ure rubber and sulphurare considered the best , because most uni form and al so becausea filler renders the reaction less delicate .

THE A NA LYS I S O F VULCA N I ZED RUBBER.

TH E pioneer work of rubber analysi s was done by Dr .

Robert Henriques and Dr . Carl O t to W eb er . F ollowingthese di stingui shed chem i st s others have worked on the probl em s and as a resul t there is avai lab le an exce l lent s elect ionof re l iab le ana lyti c methods . S tandard methods have b eenadopted for specification purposes by the United S tate s'

i ureau of S tandards, Wash ington , Di strict of Columbia ;

Am erican Society for Testing M aterial s , P hi ladelph ia , P ennsy lvania ; National B oard of F i re Underwriters ’ Laborator i es ,Chi cago

,I l l inoi s : Joint Rubber I nsulati on Comm ittee , A meri

can I nsti tute O i E l ectrical E ngineers .A complete analysi s of vulcanized rubber inc ludes1. A cetone extract : (a ) free sulphur , (b ) waxes .2 . Ch loroform extract , m ineral rubber, tar or asphalt .3 . A l coho l ic potash extract

,rubb er sub stitutes .

4 . Total sulphur .5. A sh and m ineral analysi s .6\ Rubber .7. Specific grav ity .

RENTA RKS O N A NALYS I S .

The following remarks in explanation of the analysisare f rom Circular 38 on “

Testing of Rubber Goods ,” by theUnited S tates B ureau of Standards .

A CETO N E E X TRA CT .—A C€tO l l e extracts the rubb er resin s ,

the free sulphur , and any m inera l oi l s or wag es that may

have been used . The di ff erence in amount between the totalacetone extract and the free sulphur present i ndicates something regarding the qua l i ty of the rubb er present . F or the

METHODS O F TES TS 3 13

b est grades of P ara rubb er thi s should not exceed five percent . of the rubb er . The pres ence of m inera l oil indicates thepossib i l i ty of reclaimed rubb er having b een used .

F REE SULPHUR— The free sulphur i s that part of the sul

phur origina l ly added as such / which remains unchangedafter vul canization . Smal l amounts of free sulphur are notharmfu l and i t i s difficult to place a lim i t b ey ond wh ich iti s to be considered exces s ive . A l im i t i s usual ly p laced onthe f ree sulphur in h igh-grade insulation compounds , chieflyb ecaus e it may corrode the copper wire .

TOTAL SULPHUR — Sulphur occurs in vulcanized rubberas free sulphur , in comb ination with the rubb er , and at times

o in the mineral fil lers,rec laimed rubb er , and rubber sub s ti

tutes . I t i s l imited in Specification in h igh-grade materia l inorder to e l iminate undes irab l e sulphur mineral s and preventas far as pos sibl e the us e of inferior or reclaimed rubbersand rubber sub stitutes . The inferior rubbers require a largerpercentage of sulphur than P ara for proper vulcanization ,whi le reclaimed rubber and sub sti tute s contain usua l l y largeamounts of sulphur.

A SH A ND SULPHUR I N TH E A SH .—The ash or res idue a fter

ignition , consis ts principa l ly of the non-volati le mineralfi ll ers . I t i s used in calculation of the rubb er b y diff erence .The sulphur in the ash is determined mere ly for the purposeof O btaining a correction figure and has no other significance .

B ARYTES .

'

—There i s no obj ection to the sulphur presencein m ineral fi l lers

,provided the m ineral containing it has no

injurious eff ect on the rubber,and that amount of such sul

phur may be readi ly determined . B ary tes i s such a sub stanceand is perm i tted in practical l y a l l compounds where the

amount of sulphur i s lim i ted by specifications . There areno other fi l lers wh ich as yet fulfi l b oth of the conditionsnamed .

RUBBER— The determ ination of the amount of rubberpresent in a vulcanized compound i s both important and difficult. The procedure extensively used is to calculate the percentage of rubb er by the diff erence b etween l 00

gper cent .and the sum O f the ash (sulphur free ) , tota l sulphur, and

3 14 ANA LYSES O F RUB B ER

corrected acetone extract . I t i s a s good as any method yetdevised , although not always accurate .

SPECI F I C GRAVITY . -I t i s apparent that with equal percentages by weight of ingredients, a compound of a givenspecific gravity wil l have les s rubb er per unit volume thanone of h igher specifi c gravity . I n order to insure a minimumvolume of rubb er

,specific gravi ty l im i t s are stated .

CHLORO F ORM EXTRACT.-The so—called mineral rubbers ,

such as tar,bitum inous sub stances

,elaterite

, gi lsonite , etc . ,are us ed extens ively as rubb er substi tutes . These subtancesare partly soluble in acetone , but the mate rial so removed isnot characteristic of these substitutes and not readily distinguished from vasel ine and s imi lar m ineral oi l s . P art ofthe in solub l e portion remaining after the treatment with acetone i s solub l e in chl oroform , the solution b eing very darkin color . P roperl y Vulcanized h igh-grade rubb ers yie ld onlya small amount during the chloroform extraction , the solution b eing practi cal ly colorles s .

A LCO HOLI C- P OTASH E XTRACT.— Some rubbe r substitutes

are prepared by the action of sulphur or sulphur chloride onvegetab l e oi l s . A l coholic-potash extraction detects the presence of such sub stitute s and gives some idea of the amount .P ara rubb er contains only a smal l percentage of material extracted by th i s solvent .BUREAU O F STA NDA RDS

’METHODS O F A NALYS I S .

PREPARATI ON O F SAMPLES(1) SO F T RUBBER— A sample of not less than 25 grams

Shal l be prepared by taking pieces from various parts of theoriginal sample . W i th those having cover and tube , separatesamples of each Shal l b e made . F rom fire hose remove th e

backing before grinding .(2 ) GRI NDI N G— The sample shall be cut into smal l

pieces and then run through a grinder, taking for analysi sonl y such material as wil l pas s a 20-mesh sieve . Care mus tb e taken to see that the grinder does not become appreciablywarm during the grinding . I f the nature of the material i ssuch that it gums together so that it wi l l not pas s throughthe s ieve (as would be the case with under-vulcanized sam

3 16 A NA LYSES O F RUB B ER

low a temperature as possible , us ing a gentle current of ai r. Dry

the flask and contents in an air bath at 90 degrees to 95 degreesC. ; cool and weigh . Ca l l the residue “acetone extract , uncorrected .

” Calculate the results to percentage .(11) F REE SULPHUR— A dd to the flask (paragraph 10 )

containing the acetone extract , uncorrected , 50 to 60 c .c . of distilled water and two or three c .c . of bromine . (I f the acetoneextract indicates a large amount of free sulphur, the amount ofbromine used may be increased ) . Heat gently on the steam bathuntil the solution is practical ly colorless , and filter into a 250-c .c .beaker. Cover the beaker with a watch glass

,heat to boil ing on

the steam bath , add 10 c .c . of 10 per cent . barium chloride solution , and allow the precipitate to stand overnight . The next dayfilter the precipitate on an 11 cm . 590 Schleicher and Schull filterpaper. Ignite in a smal l porcelain crucible , using a sma l l B unsenflame and not allowing the paper to inflame ; cool and weigh .

Calculate the barium sulphate to sulphur by means of the factorand calculate the percentage of free sulphur.(12 ) TOTAL SULPHUR— P lace gram of rubber in a

porcelain crucible of about 100 c .c . capacity. A dd 20 c .c . of thenitric acid-bromine mixture (paragraph cover the cruciblewith a watch glass

,and allow to stand for one hour. Heat very

care fully for an hour,remove the cover, rinsing it with a little

distilled water, and evaporate to dryness . A dd five grams o ffusion mixture (paragraph 8) and three to four c .c . of distilledwater. Digest for a few minutes , and then spread the mixturehal f way up the side of the crucible to facilitate drying. Dry ona steam bath or hot plate . F use the mixture , using a sulphurfree flame , until a l l the organic matter has been destroyed andthe melt is quite soft . A llow to cool , place the crucible in a 600c .c . beaker , and cover with distilled water. Digest three or fourhours on the steam bath . F i lter into a 800- c .c . beaker, washingthoroughly with hot water. The total volume should be about500 c .c . A dd seven to eight c .c . concentrated hydrochloric acidto the filtrate

,and heat on the steam bath . Test the solution for

acidity with congo paper,add 10 c .c . of 10 per cent . barium

chloride solution , and allow to stand overnight . F i lte r bariumsulphate as be fore . Ca lculate to percentage of sulphur present .

B UREA U O F S TANDA RDS’

ME TH ODS 3 17

(13 ) A SH — Wrap a l -gram samp le in an l l -cm. 590

Schleicher and Schul l filter paper, and a fter extracting with acetone for four hours transfer to a medium- s ized porcelain crucib le and ignite at the lowest possib l e temperature : cool andweigh .

(14 ) SULPHUR O F A SH .-A dd a few drops of concentrated

nitric ac id to the ash (paragraph stir with a small glas srod and evaporate O ff the excess acid on the steam bath . A dd

five grams of fusion mixture (paragraph 8) and heat until fused .When cool , place the crucible in a 400- c .c . beaker

,cover with

water,and heat on the steam bath for two or three hours . F ilter

into a 600- c .c . beaker (reserve the insoluble residue for testingaccording to paragraph add seven to eight c .c . concentratedhydrochloric acid to the filtrate , cover , and heat to boil ing on thesteam bath . A dd 10 c .c . of 10 per cent . barium chloride solution ,and allow to stand overnight . Treat the barium sulphate prec ipitate as under paragraph 11. Calculate the sulphur by the

factor(15) B ARYTES .

— In case the total sulphur is limited byspecification and b ary tes i s perm itted as a fi l ler

, the lattermust b e determ ined , s ince the sulphur present in thi s minera lmust b e deducted from the tota l sulphur . The barytes i s calculated from the b arium i n the ash

, determ ined as fol lowsfi l ter off the in solubl e matter after the fus ion and extractionin paragraph 14

,wash back into the original beaker with

hot water . add five c .c . of 10 per c enf. hydrochloric acid , andheat the solution on the steam bath unti l as much as possib lei s di s solved . F i l ter through the same fi lter as b efore

,wash

ing thorough ly with hot water . N ear ly neutraliz e the solution with sodium carbonate

,leaving it sl ight ly acid . Saturate

the solution with hydrogen sulphide , and when the l ead sulphide has settled fi l ter into a 400- c .c . beaker and wash thorough ly . The total volume should not be over 200 c .c . Coverthe beaker containing the fil trate

,heat to boiling, and add

10 c .c . of 10 per cent . sulphuri c acid . A l low the precipitateto stand overnight . F i lter off the barium sulphate as directedin paragraph 11. Calculate the percentage of barytes . Thencalculate the percentage of sulphur in the b ary te s by the

factor

3 18 ANALYSES O F RUB B ER

(16 ) CALCULATI O N S — (a ) Subtract the free sulphurfrom the acetone extract uncorrected ,” and report the difference as “acetone extract corrected .” (b ) Subtract the sulphur in the ash from the ash as determined in paragraph 13 ,and report “ash , sulphur- f ree . (c ) Subtract from the totalsulphur determined according to paragraph 12 , the percentageof sulphur present as barytes , i f the latter determination hasb een made (see paragraph and report the diff erence as“ tota l sulphur corrected .” Then add

'

the sulphur so deductedto the ash ,

in thi s case reporting the latter s imply as “ashcorrected . I n other words

,only the sulphur other than that

in b arytes wi l l b e deducted from the ash when the total sulphur i s corrected for barytes . (d ) Subtract from 100 percent . the sum of the “acetone extract corrected

,

” total sulphur (corrected or not , as the case may b e ) , and ash (sulphurfree , or corrected for sulphur other than barytes ) , and

call the remainder “ rubber by diff erence . (e ) Divide the“acetone extract corrected” by the sum of the acetone extract corrected” and the rubber by diff erence” and cal l theresul t “ratio , acetone extract to rubber .” I t wil l b e S implerto expres s the results in percentages . When new rubber onlyi s used th i s wil l give the percentage of acetone- soluble matter in the rubber.

(17) SPECI F I C GRAVI TY. -Make this determination in apycnometer

, us ing about 5 gram s of rubber cut i nto smalls trips

,tak ing care to avoid hav ing air bubbles adhering to

thy. rubber. Do not use a ground sample for thi s determinati on

,s ince i t i s intended to determine the specifi c gravity of

the compound as a whole . A s ide from the diffi cul ty ofcompletely removing ai r bubb les , the specific gravity of asample wh ich i s ’ at al l porous wil l b e , afte r grinding, higherthan when this i s determined on strips . Calculate the specificgravity on the basi s of water at 15 degrees C as

(18) A LCO HOLI C-POTASH EXTRACT.-F i re hose

,tested

according to the National B oard of F ire Underwriters’ specifications , ca l l s for an alcohol ic-potash extraction . I t i s performed on the dried rubber remaining after the acetone extraction . Complete method appears in paragraph 28.

A NA LYSES O F RUB B ER

(23 ) F REE SULPHUR— Trans fer the aqueous solution °

(paragraph 21) to a. 250-c .c . beaker, and heat on the steam bathuntil the ether has been removed . A dd 25 c .c . bromine water

,

heat one hour, add five c .c . concentrated hydrochloric acid,and

heat until the excess of bromine has been driven O ff . (Test foracidity with congo paper ; the amount of acid specified is sufficient i f instructions are fo llowed exactly

,and a large excess o f

acid is to be avoided . ) F ilter into a 250-c .c . beaker, add 10 c .c .10 per cent . barium chloride solution and finish the determination as under paragraph 11.

(24 ) A SH — P roceed as under paragraphs 13 and 14 .

(25) TOTA L SULP HUR — P roceed as under paragraph 12 .

There wil l b e no correction for b arytes .(26 ) CALCULATI O N S — (a ) Sub tract the sum of the free

sulphur” and “waxy h ydrocarbons” from the“acetone extract

uncorrected ” and report the di ff erence as acetone extractcorrected . (b ) Sub tract from 100 per cent . the sum O f the“acetone extract corrected ,” “waxy hydrocarbons

,

” “ash sul

phur- free ,” and tota l sulphur” and report the resul t as rub

b er by di ff erence .” (c ) Divide the “acetone extract corrected” by the sum of the

“acetone extract corrected andthe

“rubber by di ff erence” and report the resul ts under ratio ,acetone extract to rubber,” as under paragraph 16 (e ) .

(27) CHLORO F ORM EXTRA CT .-W i thout remov ing the ad

hering acetone from the rubber (paragraph 20 ) extract wi thchloroform for four hours . E vaporate off the solvent in aweighed flask or beaker

, d ry at 90 degrees to 95 degrees C.,

cool and weigh .

'

Reserve the rubb er fo r the a lcoholic-potashdeterm ination .

(28) A LCOHO LI C-POTASH EXTRACT .—Dry the rubber

(paragraphs 10 ,18

,and 27 ) at about 50 degrees to 60 degrees

C.,transfer to a 200- c .c . E r l enmeyer flask , add 50 c .c . alco

hol ic-potash so lution , and heat under a reflux condenser forfour hours . F i l ter through a folded fil ter into a 250- c .c .b eaker

,washing with 50 c .c . of 95 per cent . a l cohol , and then

50 c .c . of boil ing water . E vaporate the fi l trate to dryness .Transfer the res idue to a separatory funnel , using about 75c .c . of di stil led water . A dd a few drops of methyl orange ,and acidify the solution with 10 per cent . hydrochlori c acid .

CA LCULA TI ON O F RESULTS 321

Extract with four portions of ether, 25 c .c . each , unless thefourth portion should b e colored , wh en the extraction shouldb e continued unti l no further quantity can b e extracted . Unitethe other fractions , wash thorough ly with disti l led water, andevaporate the ether in a weighed b eaker . Dry at 90 degreesto 95 degrees C.

,cool and weigh .

The methods of rubb er ana lysi s specified by The American Society for Testing M aterial s , the N ational B oard of

F ire Underwriters’ Laboratori es , and the Joint Rubb er I nsulation Comm i ttee in genera l close ly resemb le those recom

mended by the United S tates B ureau of S tandards . The Cottleextracting apparatus i s specified in place of the al l -glas sapparatus of the B ureau of S tandards .JO INT RUB B ER INSULATIO N COMM ITTEE ’

S

METHODS .

The percentage of rubber sha l l b e considered to be the

di ff erence b etween 100 and the sum of the total sulphur andash express ed as percentages and figured on the total compound . I f the alcohol ic-potash extract i s over two per cent .of the rubb er as first calculated , sub tract th i s excess al so fromthe rubb er . The organic-acetone extract shal l be obtainedby taking the diff erence b etween the total acetone extractand the free sulphur . The organic acetone extract

,free sul

phur,total sulphur and alcoholic-potash extract shal l b e fig

ured on the amount of gum as found by the above procedure .A general outline of the procedure is given on following

page . I t will be seen that the residues from the alcoholicpotash saponification are treated with hydroch loric acid to te

move organic matter, and the part insoluble in acid is dried anddivided into two parts , one of which is used for the determination of sulphur, and the other ignited . A sulphur determination is a l so made on the ash . The rubber hydrocarbons as apercentage of the total sample are given by the followingformula

C HRubber Hydrocarbons 100

4 D G

The total weight of sample used in the determination is fourgrams and the letters C

,D

,E

,F

,G

,and H represent the weights

in grams of the Substance in the diagram. 0


A ni l ine diff ers from other solvents in that rubber dissolvedin it forms a thin solution wh ich permits the mineral fillers toseparate readily.

The small amount of nitrobenzene is used , because it makessolution more rapid . Semi- cured compounds dissolve moreslowly than thoroughly cured so ft stocks or very hard ones .With under- cured compounds a soft , pasty mass is formed ,which is very slow to dissolve , while this does not occur i f thematerial is properly vulcanized .

In some few cases an additional digestion with hal f thequantity of solvent for five hours will reduce the amount ofmineral fillers about per cent . In specification work it isadvisable to make this second digestion after the ether has beenexpelled from the tube by heating.

A nalysis of the fillers shows that the rubber as found bydiff erence will not include the sulphur of vulcanization .The sum of the percentages of rubber found and organic

acetone extract is slight ly greater than the percentage of rubber used in the recipe .

The fi l lers during vulcanization and a fterwards in thecourse o f analysis have combined with sulphur to form newcompounds . I f this combination of fillers and sulphur is a substitution of sulphur for some other acid radical , the resultantproduct would weigh less than the sum of the ingredients entering the reaction and the rubbe r found by difference would beslightl y greater thereby.

DIRECT DETERM I NA TIO N O F RUBBER BYWET COMBUSTION .

‘

TH E rubber nitrosite for combustion is prepared as follows :A fter the rubbe r sample has been ground in a meat- chopper to pas s a 20-mesh s ieve , and a V2 gram of i t extracted 3hours with acetone

,and 72 hour or longer with chloroform ,

the extracted samp l e i s al lowed to dis solve in , or thoroughl yabsorb , chloroform . A small F lorence flask (75 c .c . ) i s used ,which may b e about one-half ful l of the solvent . N i trousoxide vapors

,evolved from dilute n itric acid (Specific gravityand arsenic trioxide . are then passed through the cooled

6

L. G. Wesson and E . S . Knor r . Wet Combustion in the N itros iteCombustion Method for the Direct Determination of Rubber. Amer ican Chem ical Soc iety P roceed ing s , September , 1916 .

RUB B ER B Y WET COMB US TI ON 325

chloroform until the deep-green color becomes permanentfor

,say 15 m inutes , and the whole allowed to stand over

night for comp l etion of the action .The ch loroform i s then decanted through a dry Gooch

cruc ib l e and asbestos matte (the former rests in an ordinary60- degree filter funnel ) into the combustion flask , f rom whichthe chloroform is then evaporated by means o f a boiling-waterbath and a d ry -air current .7

M eanwh i le the re sidue in the F lorence flask has b eensim i larly dried . The s eparation of fi l lers and nitrosite i s nowbrought about in the following way : Small portions (5 c .c . )of calcium ch loride-dried ethyl acetate are added to the residue ih the F lorence flask , the latter warmed , and the l i quiddecanted through the Gooch crucib l e into the combustionflask

,repeated l y , until the fi l trate runs through enti rely col

or les s . A fter evaporation of the acetate (recovery of thesolvent as wel l ) the res idue i s careful ly freed from solventby warm ing the containing flask in a boiling water bath for

,

say,15 minutes

,after wh ich 15 c .c . of water contain ing 1

drop concentrated HCl , are added , and quick ly evaporated bythe us e of a boi l ing calcium chloride bath and b risk currentof dry air . The heating I S continued at least one-half hourafter the res idue is again apparently dry .

The combustion apparatus consists of a 200 c .c . roundbottomed disti l l ing flask , which is provided with a droppingfunnel (100 c .c. ) through a one-holed rubber s topper, and aseries of U-tubes containing in order : (1) concentratedH

ZSO ,—K2Cr ,O 7 , renewed every 1 or 2 combustions ; (2 )water containing a drop of the preceding ; (3 ) granular zinc ;

(4 ) calcium chloride ; (5) soda- l ime (weighed ) ; (6 ) sodal ime and calcium ch loride (weighed ) .

The combustion is conducted as follows : The weighedsoda—l ime tubes in pos it ion , and the combustion flask cooledby water , a vo lume (20 c .c . ) of cooled concentrated sulphuri cacid i s run rapidly into the flask on the nitrosite ; then thecooled oxidiz ing so lution of 10 grams pulverized KgCrzO 7

in7

J. B Tuttle , of the Bureau of S tandards,has found that the chloro

form sol iible res idue thus recovered may be very apprec iable and it is tohis sug g estion that th i s mod ification i s due.

326 ANA LYSES O F RUB B ER

75 c .c . c oncentrated H zSO , , i n a very S low stream . The flaskmay now b e gently warmed by a sand bath to obtain amoderately rapid evolut ion of gas“.

Th i s i s done as long as gas continues to be evolved(about one hour ) , when a carbon dioxide free current of air,the heating b eing maintained ; i s passed via the dropping funne l through the apparatus for at l east one-half hour to sweepa l l carb on diox ide into the soda- l ime tub es .W'

eight CO 2 X X 200 g ives percentageC10 H " ; in the sample .

We hope , in conclus i on , that further study and improvements of th i s method wil l eventual ly give a reliabl e and nottoo diffi cul t procedure for the direct determ i nation of rubb er ,not only i n good qual i ty compounds

,but a l so in factice and

other inferior sub stitute- containing rubbers .SULP H IDE SULP HUR.

The presence of metall ic sulphides and sulphates in technical rubber articles complicates the estimation of the combined

” sulphur . O rdinarily the free sulphur and that presentas substitute are extracted with acetone and alcoholic potash ,respectively . In the absence of sulphides and sulphates an estimation of sulphur in the residue gives the percentage in com

bination with the rubber . In the presence of sulphides and sulphates it i s usual to heat a portion of the residue with high boiling point solvents to destroy the rubber and render it soluble .The sulphur is then estimated in the washed mineral residue .The sulphur is also estimated in another portion of the extractedrubber

,and the sulphur combined with the rubber estimated

by difference .The method is unsati s factory and has two disadvantages .

F i rst , many vulcanized rubbers are decomposed with difficulty.They carbonize and cake even at carefully regulated temperatures . Consequently the residue , after washing with benzene ,contains undissolved organic matter which protects the decom

“That car bon monoxide is formed dur ing the combustion can be

shown by al lowing the g ases wh ich have passed the absorption train to

come in contact with heated copper oxide and then barium hydroxidesolution. A prec ipitate ensues , but the amount is not apprec iable for theresults o f the analys i s .


mixture a few minutes . Traces of hydrogen sulph ide areremoved by a current of carbon dioxide and the lead sulphidei s col lected

,washed and titrated iodometrical ly .

SULPHATE SULPHUR.

The residue in the Voigt flask , containing the sulphate si s extracted repeatedly with hydroch loric acid and the sulphate s determ ined as barium sulphate .

SOLVENTS F O R VULCA N IZED RUBBER A NALYS I S .

E ther,in presence of hydrochlori c acid , gradual ly di s

so lves vulcanized rubber at the ordinary temperature , and thedis solved rubb er contain s about per cent . of sulphur . A

m ixture of b enzene and hydrochloric ac id al so di s solve s vulcan ized rubber . Chlorohy d rocarbons act S imi lar ly to the mixture of So l vents and hydroch lori c acids , but are no more rapidthan a m ixture of b enzene and acids .

Douglas F . Twiss,in analyti c work on rubb er

,finds that

a m ixture of equal part s by volume of concentrated hydroch loric acid and ether acts readi l y on rubb er m ix ing s atord inary temperature,the penetrat ion of the acid being faci l i

tated by the swe l l ing acti on of the ether .A nother application for th i s reagent i s the neutralization

of accelerators,such as l i tharge , before attempting the r e

mova l of free sulphur from rapid-curing mix ing s . Wherenecessary to exam ine the content of comb ined sulphur in apartially cured rubber—mix wh ich contains much mineralaccelerator and free sulphur, the convers ion of the acceleratorinto an inert substance b efore the acetone extraction has theadvantage of remov ing the l ikelihood of vulcanization duringextraction .

To eff ect such purpose the procedure used i s to treat oneto two gram s of the rubber with the acid- ether reagent unti lth i s reagent penetrates throughout the mass . The progressof the action

,in presence of l itharge , i s easi ly fol lowed by

the change in color. The change i s usually completed in adayu The rubb er mas s can then be removed or ' the etherevaporated . The mass i s next washed in running water anddried . I t i s then ready for acetone extraction and the comb ined sulphur estimated in the re sidual rubber . I f mineral

F REE SULP HUR— M INERA L F ILLERS 329

sulphates are ab sent , the sulphur in the extracted rubber may

b e cons idered as organica l ly comb ined sulphur . I t i s saferto begin with two samples and to estimate the total free andcomb ined sulphur in one and free sulphur in the other . The

above process appears to b e desirab l e where there are largequantities of free sulphur and acce l erator . I n the oppositeinstance the method of S tevens i s perfectly sati sfactory .MT. P RO S P ECT LA BO RATO RY METHODS O F A NALYS I S .

The methods emp loyed in the M t. P rospect Laboratory ,Department o f Water Supply, Gas and E lectricity of the Cityof New Y ork

, possess novel features introduced by F rankGottsch . “

These method s are as follows :F REE SULPHUR.

—The dried acetone extract is enti relytrans ferred to a 60 c .c . iron or nickel crucible by acetone , chloroform or benzol , and the so lvents evaporated O ff on the steambath and 6 grams of potassium carbonate and four grams ofsodium peroxide are added . M ix

, cover , heat at low temperature over asbestos shield to avoid sulphur fumes, until the mixture fuses , then bring to quiet fusion for 15 to 20 minutes . A voidrapid heating and explosions and rotate the melt while solidi fying. When cool put crucible and cover into a casserole with200 c .c . of water, add five to ten c .c . bromine water and boi lmelt till disso lved . Settle , decant , filter and wash through thickfilter with hot water. Cool , acidi fy filtrate with dilute hydrochloric acid , make up to 400 c .c . and precipitate boiling withten c .c . of ten

‘

per cent . solution of barium chloride .M I N ERA L F I LLERS .

—A one-gram sample is extracted by acetone for four hours and the rubber dried in the water oven at100 degrees C. , until the O dor O f acetone is gone . Transferthe sample to a 100 c .c . beaker

,burn the thimble to ash and add

it to the beaker. A dd 50 c .c . of clear molten salol and heat thebeaker on the hot plate at a temperature of not less than 120degrees , nor more than 150 degrees C., stirring occasionally untilthe rubber is apparently dissolved . A fter settling

,transfer the

l iquid to a 200 c.c . beaker and i f the residue in the small beakercontains particles of undissolved rubber more salol is added andsolution completed . Sti r two c .c . of a one per cent . solution ofsoluble cotton in amyl acetate into the warm liquid in the 200c .c . beaker, cool and add redistilled turpentine unti l a good


flock has formed , adding at least 75 c .c . of turpentine withconstant stirring. A llow the liquid to stand until the flocksettles . The supernatant liquid is decanted and filtered by suction through an alundum crucible placed in a Spencer holder.Wash the flock by decantation with turpentine, filtering the latter ; transfer the whole to the crucible , then dissolve care fullyin a few c .c . of acetone , and wash the fi l lers with acetone , beingcare ful not to a l low the fillers to cover and clog the sides O fthe crucib le . A ll beakers and the crucible are to be thoroughlywashed with acetone . Dry to constant weight at 105 to 110 deg rees C. , coo l ing in a desiccator. Evaporate al l the filtrate andwashings , trans fer to a weighed porcelain dish ,

burn O ff the or

ganic matter . A dd weight of residue to that o f the fillers in thecrucible and calculate as mineral fillers .

F ORE I GN A LCOHOLI C P OTASH EXTRACT— The dry rubberresidue f rom the acetone extract is extracted with 50 c .c . O f

alcoho l ic potash , stoppered , in an air oven kept between 105 and110 degrees C. , for four hours . Cool , filter and wash the residuec lean with hot absolute alcoho l . P recipitate potassium chlorideby acidi fying fi ltrate strongly with hydrochloric acid , settle , filter and wash with hot chloroform and evaporate the fil trate ona steam bath ti l l odor of hydrochloric acid just disappears . Takeup residue with chloroform ,

filter and wash with hot chloroforminto a beaker, and evaporate to dryness . I f the residue is notoily or greasy to touch , it may be disregarded . I f 0 i or greasythe residue is washed with small portions of 88 degrees B eaumenaphtha

,filtered through a washed plug of cotton into a smallweighed beaker

,evaporated and dried in water oven at 95 to

100 degrees C . in 15-minute periods until the weight is constant

,or increases . The resul t is calculated as foreign alcoholic

potash extract .”VULCAN I ZED RUBBER GUM B Y WE I GHT.

— Subtract the sumof the percentages of free sulphur

,organic acetone extract, , min

era l fillers and corrected foreign matter from 100 per cent . The

ba lance is the vulcanized rubber gum by weight .VULCAN I ZED RUBBER GUM B Y VOLUME — Multiply the per

centage by weight O f vulcanized rubber gum by the specific gravity . The product i s that specified by the term vulcanized rub

ber gum by volume .


ELECTRO LYTIC METHODS .

E LECTRO LYTI C M ETHOD F OR LEAD A ND ZI N C I N VULCAN I ZEDRUBBER— The folloiving method is by E lmer D. Donaldson .The portion re lating to the deposition o f zinc on platinum directis adapted from a method by W. S . Kimley .

Donaldson’s method consists of digestion of the ash in nitricacid and precipitation of lead as peroxide (P bO g ) , followed byevaporation and precipitation of zinc as metal , both on platinum .

The electrolytic apparatus was equipped with a rotating electrode

and pole- reversing switch . The larger -electrodes were of platinum gauze 172 inches wide by 2 inches high , sand blasted , andthe rotating gauze inch wide by 2 inches high . The apparatuswas connected to a 110- vo lt direct current generator and lampresistance .

Lead — Weigh one gram rubber, wrap in a seven- centimeterash l es s paper and incinerate in a 20 to 30 c .c . porce lain crucib l e .B rush the ash into a 200 c .c . electrolytic beaker, add 25 c .c . concentrated nitric acid , and digest on hot plate for 15 minutes .B oil to expel nitrous fumes and dilute to about 125 c .c . , havingsolution at 158 degrees to 176 degrees F . E lectrolyze withrotating cathode

, using direct current O f two to three amperes .The lead will appear on the large gauze anode as peroxide, blackwhen in large amounts , b ronze colored when in smal l amounts .E lectrolyze 30 minutes and wash anode thoroughly with waterto remove mechanical impurities , then with alcoho l and ether.Dry for 30 minutes at 338 degrees F . Weigh as peroxide oflead (P bO z ) and for convenience calculate to litharge (P hO ) ,using the factor No metals present in rubber mix ing s wi l linterfere with this determination .

Zinc—Wash the solution and the insoluble matter from the

electrolytic beaker,from which the lead has been removed , into

a litre beaker . A dd five c .c . of concentrated sulphuric acid ,evaporate dry

,and drive off most of the sulphuric acid . This

is done to insure complete removal of nitric acid , wh ich wouldinterfere with the electro deposition of zinc . A fter evaporation ,c ool and digest residue , which usua lly contains considerable insoluble, with 50—75 c .c . water. The zinc i s now present as zincsulphate and is readi ly soluble . F ilter and wash . I f the zincoxide content is known to be low use entire filtrate , but i f 20 per

INSULA TI ON S P E CI F I CA TI ON 333

cent . or over, catch filtrate in 200 c .c . volumetric flask . Makeup to mark and take 50 c .c .Wash this portion of solution representing grams O f

rubber sample into a 200 c .c . electrolytic beaker . A dd considerable excess o f saturated solution of sodium hydroxide over thatnecessary to redissolve the zinc hydroxide . E lectrolyze at ordinary temperature at 2 to amperes , rotating the anode for 20minutes . Remove and wash with water, alcohol and ether. Dryat 212 degrees F . for a few minutes , cool and weigh .

Zinc i s deposited on the cathode and i s weighed as metal .The weight of zinc is calculated to zinc oxide. A luminum willnot interfere even i f the solution is gelatinous f rom the precipi ‘fated aluminum hydroxide . In event that i ron is present

,filter

off the iron hydroxide after adding just enough sodium hydroxide solution to insure solution of the zinc hydroxide . Then addfurther sodium hydroxide solution to this filtrate . Lead peroxideand zinc can be dissolved from the platinum gauze by concen

trated nitric acid saturated with tartaric acid .JO INT RUBBER INSULATIO N COMM ITTEE

’

S S P ECI FICA TIO NF O R 30 P ER CENT. H E VEA RUBBER COM P OUND.

(CHEM I CA L

1. A 30 per cent . fine P ara or best quality plantation Hevearubber compound with mineral fil l ers Shal l b e furnished . I t

Shal l contain only the fol lowing ingredients : (1) rubber ; (2 )sulphur ; (3 ) Inorganic mineral matter ; (4 ) refined oil paraffin O r ceres in .2 . The vul caniz ed compound shal l conform to the fol

lowing requi rements,when tested by the procedure of the

Joint Rubb er I nsulation Committee,results being expres sed

a s percentages by weight of the whole sample .REQU I REME N TS I NDEPENDENT O F TH E AMOUNT O F

RUBBER F OUND. Maximum .

Rubber 33Waxy hyd rocarbons 4Free sulphur

Red lead,carbon , or organic fil lers shall not be present .

”

Joint Rubber Insulation Committee Report in The Journal of Industr i al and Chemical Eng ineeri ng ”

(March , The procedure isoutl ined elsewhere in this chapter .

A NA LYSES O F RUB B ER

REQUI REMENTS DEPENDENT UPO N AMOUNT OFRUBBER F OUND.

(Requirements for intermed iate percentag es shal l be in proportion to the

percentag e of rubber found .)30 P er Cent. 33 P er Cent.

Rubber Compound. Rubber Compound .

Maximum. M inimum . Maximum. Minimum .

Saponifiable acetone extractUnsaponifiable res insCh loroform extractA lcohol ic potash extractTotal sulphur (Note 2 )Spec ific g ravity3 . The acetone solution shal l not fluoresce .

4 . The acetone extract (60 c .c . ) Shal l be not darker thana l ight straw color.

5. Hydrocarbons Sha l l be sol id , waxy and nOt darkerthan a l ight b rown .

6 . Chloroform extract (60 c .c . ) shal l b e not darker thana straw color .7. F ailure to meet any requirement of thi s specification

wi l l be considered sufficient cause for rej ect ion .8. Contam ination of the compound , such as by the us e

of impregnated tapes , wil l not excuse the manufacturer fromconforming to thi s specification .

Note 1. Th i s specification shal l b e supplemented byappropriate clauses relating to tensi le strength

,elas ti city ,

electric insulat ion res i stance and diel ectri c strength . (See theW i re and Cable Specifications of the American Soci ety forTe sting Materials , the A s sociation of Rai lway E lectricalE ngineers , etc . , for examples of such clauses . )

Note 2 . The l imit on total sulphur may be omitted atthe option of the purchaser .

Experience has shown that compounds of the grade whichcontains only good Heven rubber, may be rel ied Upon to be morepermanent than those made of rubber o f other grades . It is notaffi rmed by the committee that a compound which conforms withthis specification is neces sarily permanent , or that a better compound cannot be made , but it is believed that enforcement ofthe specification will l imit the use of in ferior materials and thatit will put the manufacturers more nearly upon equality of endeavor , where they can use thei r experience to obtain the best

336 A NA LYS ES O F RUB B ER

The chloroform extract is l imited ; first,to prevent the use

of b ituminous substances , and , second , to limit depolymerizedand under- cured rubber.

The alcoholic potash extract i s limited to prevent the use of

saponifiable rubber substitutes .The specific gravity i s l imited to reconcile the specification

of ingredients by weight with the practice of purchasing materialby volume .

F luorescence of the acetone solution is prohibited , as it ind icates the presence of b ituminous substances , rosin oil or mineraloi l s .

The color O f the acetone extracts i s specified to conformwith the normal color of the extract of Herred rubber. A darkercolor indicates adulteration or an inferior grade of rubber .

The hydrocarbons are required to b e solid in order toprevent the use of oils and paraffin of low-melting point . The

shade required is that Obtained from paraffi n wax or ceresin .Liquid hydrocarbons indicate reclaimed rubber softened withmineral oil , or paraffin of low-melting point .

The color of the ch loroform extract i s specified to conform with the color o f di sso l ved gum i n sma l l quantiti es .The presence of bitum inous sub stances would b e indicatedby a b rown or b lack color .

I t would b e des irable that the sulphur of vulcanization bel im i ted to exclude reclaimed rubb er which contains the Sul ~phur of i ts prev ious vulcanization , but the committee has noty et deve loped an acceptab l e method for determ ining thi squantity . I t i s

,therefore

,confronted with the choice of ei ther

p lacing a lim i t on the tota l sulphur or giving up the attemptto exclude shoddy b y sulphur limi tat ion . O ption i s , therefore ,given to the purchas er to ins ert or omit the lim i t '

O n totalsulphur . Such insertion wil l at times exclude reclaimed rubber and the committee b el i eves i t pos s ib l e to make a suitablecompound with this l im itation . The comm itt ee th inks thata sulphur l imi t posit ively excluding reclaim ed rubb er , wouldplace too great a hardship , i n other way s , on the manufac

turet s . .Where the specification i s used with no total sulphurlimit,

'

the us e of many kinds of,or much

,

reclaimed rubber ,wi l l be gu arded against by the l im i t s of the various compo

P HYS I CAL TES TING O F RUB B ER 337

nents of the acetone extract . When the limitation on tota lsulphur i s om i tted , sulphur-bearing fi l l ers , which posses s certain advantages , may be used .This specificat ion should b e supplemented by appropriate

e lastici ty and tensil e strength tests , in order to add to theas surance that good rubb er has been used and that the vul

canization process has been properly carri ed out ; also byappropriate electri c . stres s and res istance tests , to assureproper insulating qualiti es and homogenei ty of structure . The

exact value of the l im i t s for these tests wi ll depend upon theuse to which the material i s to b e put.

The Joint Rubber Insulation Committee’s chemical clauses ,or analytical procedure for insulation , have been adopted by thefollowing

A merican E lectric Rai lway (E ngineering) A ssociationS tandard Specification for Rubb er I nsulated W ire and Cab le .

American Society for Testing M aterial s : P roposed specifications for Insulated Wi re and Cable ; 30 ,

per cent . HeveaRubber.

A ssoc iation of Railway E lectrical Engineers : S tandardSpecifications for W i re and Cable .

I nterborough Rapid Trans it Co . , M otive P ower Department

, N ew Y ork : Specification No . 2 .

N ew Y ork Central Rai l road Co . , E lectrical Department :Specification N O . 300 .

P anama Canal : O ffice of General P urchasing A gent,Cir

cular No .

S ignal Corps, U. S . A rmy : Genera l Specification No .

581-A .

P HYS ICA L TESTING O F RUBBER GO ODS .

THERE i s a great variety of special app l iances that aff ordreally valuable test s as to the durab i l i ty

,tens ile strength and

wearing qua l ity of certain kinds of goods . A s a rule , theseaim to subj ect the vulcanized art icl e to condit ions equivalentto those to which i t wi ll b e sub j ected in actual service . F or

rubber boots and shoes , for example , a machine i s employedwhich bends the shoe exactly as it i s b ent when the weareri s walking, and at the same time gives a friction mot ion on

ANA LYSES O F RUB B ER

the sole . Thi s i s run at hi gh speed , so that a week’s wear onthe mach ine corresponds to a month of service in actual use.

A machine i s al so used for testing air-b rake hose whichcounterfeit s the swing and kink ing motion that the hose getsin actual service . The hose wh i ch stands thi s sort of usagelongest i s supposed to be adapted to endure the longest timein actual use.

Ti re s,both pneumatic and solid

,are tested by being put

on a whee l r im and run the equivalent of hundreds and thousands O f miles over roughened surfaces Upon which they arepressed by a lever carrying heavy weight . These mechanica lcontrivances are valuable in showing the severe usage thatrubb er wi l l often stand , but none of them are exact paral lel sto ab solute service , for as a rul e th ey are more severe , particular ly in the i ntense heating that may come to the rubberfrom high speeds and great friction .

Manufacturers and purchasers o f rubber goods have alsomany S imple and excel l ent tes ts for approximating the va lueof the rubb er. I n belt and hose covers and tubes , a strip ofthe rubb er i s removed from the fab ri c and stretched to Showit s tensi le s trength . The fab ric i s al so pul l ed apart , and theintegrity of the fri ction proved by the way it re si st s suchseparation . Rubber Springs sometimes have b een placedunder a steam hammer

,which was allowed to drop upon

them ,the result s b eing noted and that compound standing

up longest b eing considered the best .STANDARD METHODS F OR PHYS I CAL TESTI N G.

The following methods are standard for the physica lexam ination of vulcanized rubber goods as specified by theB oard of E stimate and A pportionment of N ew Y ork City :

SAMPLI N G— The contracting department sha l l s elect andtake al l sample s for testing . The number of samples and thequantity to b e taken from the del iverie s will depend upon thesiz e of the artic les and the quantity del ivered .

Samples shal l fairly represent the del ivery,and pieces

shal l b e . taken from not les s than one per cent . of the numberof units delivered .

340 A NA LYSES O F RUBBER

When naphtha has b een used th e test piece s Shall bea l lowed to remain at rest for not l ess than one hour beforetesting .

I n all cas es where backing i s removed and bufling done ,the test pieces Shall remain at rest for not l ess than ten m ih r

ute s before tes ting .F R I CTI O N TE ST P I ECES — Test pieces for frict ion or adhe

s ion tests shal l be cut and prepared as fol lows :A ll k inds of hose , round pack ing and similar articles

shal l b e cut t ransversely unless the diameter i s so small thata practi ca l measurement cannot b e’ taken

,in which case the

test pieces Shal l b e cut longitudinally .B elting , packing or gasket material may b e cut in any

direction .Test pieces from washers , ferrules (sleeves) , molded gas

kets and other odd—shaped arti cles Sha l l b e prepared in themanner cal led for in ’

the unit specification , i f i t I S Impracticable to prepare them in accordance with thes e rul es .Cotton rubber- l ined hose test pieces and braided hose test

pieces shall be accurately cut transversely two inches wide andfull length of the circumference] They shall be cut through thewa l ls so that they can be laid out flat the full length of the piece .O ne—quarter inch of the rubbe r lining shall be carefully andcleanly trimmed O ff on each S ide, without injuring the fabric

,

leaving a strip of rubber lining one and one-hal f inches wideundisturbed on a strip of cover two inches wide . A separationb etween l ining and cover of thi s s trip shal l be started forabout one and one-half inches .

Test pieces of wrapped hose , round pack ing and Similararticles shall be accurately cut transversely one inch wide and '

left circular, to .permit sl iding on to a mandrel . A separationbetween the rubber and the fabric or between the layers inaccordance with the test to be made shall be started full width ofthe piece and far enough distant to permit proper fastening ofclamps or hooks , as the case may be .

Solid round packing and similar articles Shall have a coredrilled out for the mandrel .

F abri c-backed rubber packing test pieces shall be preparedin the same manner as for cotton rubber- l ined hose , except

ME THODS F OR P HYS I CA L TESTING 341

that if the rubb er part i s more than one-eighth inch thick , thetest piece Shal l b e prepared exactly opposite , l eaving a strip ofsheeting one and one-half inches wide on a strip of rubber twoinche s wide . A s eparation between sheeting and rubber shal lb e started for about one and one-half inches .

B elting test pieces shall be accurately cut one inch wide andshall be stripped down to all but two plies , and a separation ofthe two plies started for about one and one-hal f inches.

A ll pieces o f flat material , such as packing, gasket , belting,etc . , Shall be cut not less than 12 inches long when'ever possible .

DETERM I NATI ON O F TEN S I LE STRENGTH .

The determination of tensile strength O f the rubber compound sha l l be made as fo l lows

A PPARATUS .-A ll tensile strength tests shall be made on an

apparatus the general design of which con forms to the Schoppermachine.

GRI PS — When bar-test pieces are used , the grips for holdingthe test pieces shall be such that they will tighten automatically,exerting a uni form pressure proportionate to the applied tensionacross the full width o f the piece , regardless o f any variation inthe thickness o f the rubber.

RI NG—TEST P I ECES — These shall be placed over the revolving rollers o f the Schopper machine .

MARK I NG B A R-TEST P I ECES — The bar- test pieces shall bestamped in center portion with two lines two inches apart, usinga rubber ink-pad stamp . The distance between the outside edgesof these stamped lines shal l be accurate to one one-hundredthof an inch .

MEASUREMENT O F B A R-TEST P I ECES .—The width and thick

ness of the test pieces shall be accurately determined at threepoints equidistant between the marks , a spring gage or ratchetstop micrometer being used .

M EASUREMENT O F RI NG—TEST P I ECES .—The width and thick

ness of the test ring shall be accurately determined at not lessthan four opposite points on the ring, care being taken to getthe minimum cross section as near as possible , the area of whichsha l l be used in computing the tensile strength .

B REAK I NG— B ar- test pieces shall be tightly fastened in thejaws and brought just taut . The machine shall then

'be started


and the speed so regulated throughout the entire test that thej aws separate at the uni form rate of 20 inches per minute .

The number of pounds necessary to break the test p i ece shallbe read to the nearest tenth O f a pound and computed to poundsper square inch , using the measurements nearest to the break.When break ing the ring—test piece the ring shall be S lipped

over the revolving bearing provided for it and the procedurecontinued exactly as for the bar - test piece , the speed being soregulated that it will give an equivalent elongation of test pieceper minute .

TEN S I LE STREN GTH ACROSS TH E SEAM .

B ar and ring—test pieces shall be prepared as usual , exceptthat the seam shall not be buff ed off .

In cutting, the seam shall be centered in the middle of thebar- test piece

,at right angles to the axis , as nearly as possible .

The center o f the seam shall be made to lie along a diameterof the ring- test piece as nearly as possible .

The calculation shall be based on the average cross sectionin both kinds of test pieces in the usual manner, but excludingthe cross section of the seam or seams .

ELO N GATI O N A T TH E BREAKI NG PO I NT.

The elongation at the breaking point shall be accurately determined during the tensile strength test as follows :

O n the bar test a rule graduated to hundredths O f an inchshall be kept Opposite the two marks and the distance the outside edges O f these two marks are apart at the instant of breaking shall be noted .

This distance shall be computed into per cent . of elongation ;i . e i f the marks are twelve inches apart at the break, that piecewould have 500 per cent . elongation .

RI N G—TE ST P I ECES .

— These shall have the elongation readto the nearest whole per cent . from the automati c record onthe stretch tapes .

DETERM I NATI ON O F SET.

The dete rmination of set Shall be on the test piece as brokenin the tensi le strength test not less than one nor more than one

344 A NALYSES O F RUB B ER

F RI CTI O N TE ST.— The qual ity of fr i c tion Shall be deter

m ined by suspending a 20—pound weight from the separatedend of the duck of one of the l - inch test specimens previouslydescribed

,the force being applied radially. The separation

Shall b e uniform and regular , and the average speed shal l notexceed 8 inches in 10 m inutes

,the di stance being measured

whi l e the weight i s s ti l l in place .STRETCH I NG TE ST .

— Test specimens from tube and coverwi l l be quickl y stretched unti l the 2- inch marks are 10 inchesapart and immediately released . They will then be re-markedas at firs t wi thin 10 s econds after starting to release and againstretched to 10 inches b etween the new marks , remaining sostretched for 10 minutes . The specimens Shal l then be completely re leased , and with in 30 seconds after start ing torelease the distance b etween the marks last applied wil l bemeasured

,and the in itial set must not be more than MI inch .

A t the end of 10 m inute s the di stance b etween the marks willagain b e measured , and the final set must not be more thaninch . These t est spec imens may be cut from the tub e andcover of the friction- te st specimen

,but Sha l l not be used for

tensi le test .TEN S I LE STRENGTH .

—Test specimens from tube and covershal l b e pul l ed in a tensi le machine with a test speed of 20inches per minute . The inner tube mus t have a tens il e strengthof not les s than 800 pounds or more than pounds persquare i nch , and the cover not les s than 700 pounds or morethan poi md s per square inch . The elongation Shall besuch that the marks , original ly two inches apart , stretch to atl eas t 10 inches before specimen breaks . I f the tensi le s trengthin pounds per square inches i s greater than that required ,the sample may b e accepted , providing the per cent . increasein elongation i s equa l to or greater than the per cent . increasein tens i le st rength in pounds per square inch above the maximum figure .

P ORO S ITY TEST—The rema i n i ng 17 i nches Sha l l b emounted and placed in a test rack ; the circumference willbe measured and the hose fi l l ed with ai r at 140 pounds pressure per square inch ; the rubber cover shall be cut from clamp

ME CHAN I CA L AND CHEM I CA L P RO P ERTI ES 345

to c lamp (taking care not to injure the duck ) and th i s pressure maintained for five minutes . A t the end of th i s timethe hose will b e submerged in water to determine whetherthe inner tub e i s porous . The escape of ai r through the tub eshall be dist inct enough so that porosi ty wil l not be confus edwith the escape of air wh ich i s confined in the structure ofthe hose . I n the event the hose fai ls on bursting test at thepoint at wh ich cut was made for poros i ty test and a satisfactory hydraul ic tes t i s not obtained , the porosi ty ,

and hyd raulic test wil l be repeated on another piece of hose .

B URSTI N G TE STs .—The section of hose , which was used

for porosity tes t , shal l then be subj ected to a hydraul ic pressure of 200 pounds per square inch , under wh ich pres sure itshall not expand in circumference more than inch for airb rake hose and H, inch for air- s ignal hose , nor develop anysmal l leaks or defects . A fter the above test , thi s s ection Shal lthen stand a hydraul ic pres sure of 500 pounds per square inchfor 10 m inutes

,without bursting or developing any sma l l

l eaks or defects,after which the hydraul ic pres sure shall b e

increased to a minimum of 700 pounds per square inch without bursting , at the rate of not l es s than 100 or more than200 pounds per five seconds .

RELATIO NSH I P O F MECHA N ICAL TO CHEM ICAL

P RO P ERTI E S .

n

F ROM experiments made there i s no quest ion that thecombined sulphur at “optimum cure in the case o f Hevea plantation rubb er i s a remarkab ly constant quantity , equal on theaverage to approximately -3 per cent . Where more thanth i s amount of combined sulphur has been found , either themethod of vulcanization i s at fault or the means of determining the

“optimum” cure are inaccurate . I n th i s connectionit i s necessary to point out that in the case of very soft , lowgrade rubbers it i s difficul t to judge of the “optimum” cure ,and there i s a lways the tendency to increase the cure to bey ond the “optimum” point in the hope of thereby improvingthe physical or tens il e properties of the product . I n the caseof any good grade O f Hevea plantation rubber there is no such

“Doctor D. Spence.

“

On the Relationsh ip o f Mechanical to Chem ical P rope rti es .

” “Ind ia Rubber Journal ,” December 9, 1916.


O

difficul ty,however

,and where more than -3 per cent . of

combined sulphur i s reported in thi s case,either the sample

i s over-cured,or what amounts to the same thing

,vulcaniza

t ion has not b een proper ly carried out. W i th proper methods of vulcanizati on , and with the requi s i te experience inthe judging of the proper cure

,the comb ined sulphur at

“optimum” cure should never great ly exceed the figures wehave g iven . I t should b e pointed out, however , that if thetime of cure required to produce the “optimum result i sex tended , the chances ar e an increase in the amount of thecomb ined sulphur at the “optimum” point over the figureswe have given wi l l be found . Depolymerization

,requi ring an

increase in cure to b ring the rubb er up to apparent physica l“optimum” l eads to ‘ an increase in the comb ined sulphur cons iderab ly over the amount wh ich we have given . The rubberin this case is , nevertheless , overcured , and where the vulcanization of the rubb er i s carri ed out scientifical ly

,i n a

m inimum of time , and with the least pos s ib l e injury to themolecul e , the comb ined sulphur at “O ptimum” cure wil l neverbe found to exceed three per cent .Whether these figures ob tain for rubb ers of diff erent

botanica l origin or not we have not suffici ent analytical evidence at present to say . The constancy of thi s resul t i sdeduced from experiments made on Hevea B ras iliemis rubberon l y . The re lation between the rubber and combined sulphurat correct cure i s SO constant that i t i s regarded as representing a more or l es s definite compound of rubber and sulphurto wh ich a formula may be as signed on the assumption thatpartial valencies of the rubber aggregate have not al l thesam e affinity for sulphur .

I t may be of interest to record the fact that we haveob s erved that the point at which the physical propertie s ofpure balata on vulcanization suddenly change to more nearlyresemble those of rubb er

,corresponds very closely with a

combined sulphur content of three per cent . I f pure balatai s m ixed with al itt le sulphur and a sui tabl e catalyst , whi ch i sessential to its proper vulcanization

,it wil l b e found that

when about three per cent . of sulphur has combined with theba lata , the phy sical properties of the vul caniz ed balata change


ard curve or other m ethods are correlated to manufacturingconditions and the t ests carri ed out on rigidly standardizedl ines .

Vulcanization is essential ly a chemical proces s ; so also i sthe sub s equent decomposition of rubb er which has been overcured

,and hence the proportional re lationship of rubb er and

sulphur in comb ination i s the b est guide for a s tab le product ,the first es sential in the manufacture of rubb er goods .

Di scus s ing the case in wh ich the“coeffi cient” (according

to S tevens ) may b e wrong , but the mechanical propertiescorrect

,Schid rowitz and Goldsborough note that the question

at i s sue i s whether state of cure or correct cure i s to bejudged by the chem ical or the mechanical properties of thevulcaniz ed artic le- by sulphur comb ined with the rubb er orby the stressstrain curve . Their answer is that ultimately theattributes or quali ty of vulcaniz ed rubber must b e judged bythe physica l or mechanical properties .Certain low-curing rubb ers requi re , in order to acqui re

the necessary mechanical properties , a protracted cure , and inthe course of such cure will combine with more than three percent . of sulphur, and in general slow-curing rubbers deteriorate more rapidly than rapid-curing goods , and will not agewell because of the excess of combined sulphur , and possibl yal so by reason of the long heating neces sary .

The physica l and mechanical effects which vulcanizationhas upon rubb er are shown in the clearest manner by the

stres s- strain curve m ethod , and there i s no other knownm ethod whereb y the mechanical aspect of vulcanization canbe systematical ly and accurate ly fol lowed and measured .

Regarding this method , its authors , Schidrowitz and Goldsborough remark

I n v i ew o i the apparent lack of comprehens ion concerning s tress- strain curves . we take th i s opportunity of b ri eflyre- stating some of the more important points .

1. The“type of the curve i s ind ependent of the state of

cure . I t therefore connotes inherent properties .2 . A s the “type” varies for diff erent rubbers , its determination affords a valuable method of comparison in regard toimportant mechanical properties .

S P E CI F I C GRA VI TY IN . COM P OUNDING 349

3 . We obtain a graphic representation of the progress ofvulcanization .4 . We are able to cure to a definite mechanical condition ,and to estimate the rate of cure necessary to attain that con

dition .5. Having settled the position of the curve for a given rub

ber mixing we are able to control the vulcanization of the factory product .Much else may be done with and deducted from the stressstrain curve method . In more propitious times the authors propose to recur to the subj ect at length .While agreeing that stressstrain curves are of great value ,

intelligently applied , Dr . S tevens holds that the coeffi cient ofvulcanization is the safest guide as to the state of cure .

S P ECI FIC GRA VITY IN RUBBER COM P OUNDI NG.

TH E relation of bulk to weight depends on the Specificgravity of the material and is of great importance in the rubbe rindustry because it controls the number of pieces pe r pound inmolded rubber goods , and the rubber-coated area obtainable perpound in the case of coated fabrics , f rom any given stock .

The specific gravity of any substance is the particular'

ratio

of its weig ht to that of an equal bulk of another substance takenas standard , or unit weight. F or all solids and liquids, the standard substance of . unit gravity is distilled water at 62 degreesF . F or gases the standard is hydrogen gas at the atmosphericpressure O f the sea level .

The method of determining specific gravities o f solidsdepends On the fact that any insoluble substance immersed inwater loses weight equal to the weight of the volume of waterwhich it displaces . The means o f asce rtaining specific gravitiesvary according as the substance under examination is Sol id ,l iquid , or gaseous .

In the case of solid bodies,not in powdered form, a balance

or other weighing apparatus i s employed by which the weightof the material in ai r and its 1655 of weight in water may bedetermined . These values hav ing been found experimentally,the specific gravity is ascertained by dividing the weight of thematerial in air by its loss of weight in water . F or rapid determinations of spec ific gravity, special instruments are often used ;

350 ANA LYSES O F RQB B ER

for example , the spiral balance, or a direct reading instrument ,known as a gravitometer.

F or materials in the form of powder the specific gravitybottle is used . This is o f various forms , but i s essentially asmall glass- stoppered flask provided with a reference mark onthe neck . A fine chemical balance is necessary to make theweights and the procedure is as follows“ , for solids heavier thanwaterWeigh the flask filled to the mark with water, then place the

substance , of known weight, in the flask, fill to the mark withwater

,and weigh again . The calculation of the specific gravity

will be(We ight o f substance in air ) (weighto f flask and water ) (we ight of flask

and water and substance ) .

Spec ific g ravity(W

'

eight of substance in air ) .

I t should be noted that specific gravity is not to be takenas a test for quality as applied to rubber compounds , but shouldbe considered simply as a factor in the economy of any givenstock . A practical application is found in estimating the weightof a proposed article when its net cubical contents of stock isknown . The weight for water of the cubical contents is ascertained by multiplying by the weight in grains of one cubicinch of water. This product, multiplied by the specific gravity ofany material , will give the weight o f the Obj ect in that material .From Bai ley’s “

Chem ists’ P ocket Book.

352 DI VI S I ONS O F RUB B ER MANUF A CTURESome manufacturers , following A ustin G. Day’s ideas , have

used alkaline solutions in washing certain gums , to neutral ize thevegetable acids

,and it i s a question i f it might not be as wel l to

use dilute acids to neutralize the strong alkaline qual ities ofgums that go through certain k inds O f coagulation . Some factori es al so examine the coarser grades of gums , chemical ly , andg ive them a treatment to remove odor . A s a rule , however,manufacturers rush them through the washing machines , sheetand dry them

,and get them into the mixing mills as soon as

possible .DRYI NG— The drying of rubber, according to earlier practice

,requi red a great deal of time . I t was the boast o f more

than one rubber mill that no P ara rubber was used by them untilit had been dried for a year. The manufacturers of mechanicalrubber goods were the first to break away from this tradition .In many cases they found , when there were rush orders on hand ,that they must put on their mills g um that was practically justoff the washer

,and mix it , or el se lose orders . O f course , they

were forced to get most of the moisture out, or neutralize whatwas le ft , and they learned incidentally that they got a strongercompound with the green gum than with the “seasoned , whencethe belie f grew up that the months

'

and years of drying werenot necessary , as had be fore been supposed In addition to this ,some of them learned that long drying meant oxidation on theoutside , or the turning of rubber into resin , which further increased their doubt of the wisdom of the slow-drying process .

These thoughts once entertained , it was not long be forevarious plans were introduced into the drying

,for hastening the

removal O f the moisture . The simplest o f these , of course , wasartificial heat , and the presence of a fan for removing themoisture- laden atmosphere . Later developments have broughtabout a process , lasting only a few hours , for d rying rubbervery cheaply at quite a high heat , thereby giving it hot from thed ryer to the man who runs the mixer, and doing away with theexpensive process of breaking down . This latter idea i s to some ,of course , as revolutionary as was the first thought of quickdrying, but that it is wholly in the line of progress is proved bythe fact that it has now been used for a number of years bymany manufacturers whose goods stand very high .

M ILLI NG— CA LENDER ING 353

MI LLI NG— The milling of crude rubber i s simply putting onhot rolls the dry rubber which is found in a tough , intractablesheet, and running it until it gets to be a so ftened , homogeneousmass . ’

The gum,when this is accomplished , is ready for mix

ing. These mixing rolls are run at diff erent speeds and arecalled friction rolls , and the various adulterants and ingredientsthat are to be incorporated with the rubber are pressed into thesoftened gum by their revolution .

No general rule can be laid down for mixing in all l ines .A n expert compounder knows that certain g iims should bemixed on cool rolls , and others under considerable heat . Hi sknowledge of specific compounds teaches him to hasten mixingin many cases , where another, without sk ill , would requi re verymuch more time to get the same result . In some cases the ing redients are put in together, in others it i s necessary to addthem in definite order . Some have dissolved substances thatwould make the rubber stick to the rolls like glue unless theywere put in at just the right time ; others have so large a proportion of earthy matters that , un less the gum be humored , itapparently wil l not take them in , and so on . E ach l ine of workand , in fact , each factory has its own ‘ special methods , and oftenone or more Sk illed mixers who can handle compounds thatnone O f the others seem to be able to do anyth ing with .

CALENDERI NG.

—The use of the calender i s to Sheet thegoods so that they may be easily made into the desired forms .The S implest form of calender is a mixing mi l l with the keywithdrawn that normally holds one roll in place

,so that both

run by even motion . This is used in many sma l l factories wherenothing but molded work i s made .

The modern Sheeting calender i s ordinari ly a three—rollmachine . I t i s sometimes made with four or more rolls , however , and these rol ls may be almost any size , the widest forrubber work being more than 80 inches . A considerable degreeo f Sk ill i s required for running the calender on a variety ofstocks , nor can any general rules be laid down for calender work .

This is proved by the value that is set upon good calender men,and by the diff erence that there is between the work of a good

one and a poor one . There are as many diff erent kinds of calenders as there are patterns of mixing mills . A sheet calender

354 DI VI S I ON S O F . RUB B ER MANUF A CTUREhas smooth rolls , and is for running absolutely smooth goods .I n shoe work there are engraved rolls , pebb led roll s , and SO 1ing calenders engraved with knurled surface to produce therough shoe sole . The carriage drill business has embossing calenders

,and so on . A type of calender that is use ful in most

l ines o f work i s known as the friction calender, the rolls in whichrun at uneven speeds and drive the gum deeply into or throug hthe meshes of the fabric .

SPREADI N G. Where india rubber is handled in solutionthere i s used in place o f the calender aspreading mach ine , knownunder the various names o f “Y ankee flyer,” “

English spreader,”“doughing machine ,” etc . In th i s a sheet of rubber is Spreadon the cloth by being placed on an endless apron of the fabric ,the apron running over the roll

,against which hangs a heavy

knife . A very thin coating of the rubber solution is constantlyscraped off thi s surface , which then passes over hot drums orsteam chests

,evaporating the solvent .

DIV I S IO NS O F RUBBER MA NUFA CTURE A ND TYP ICALCOM P OUNDS .

TH E foremost European manufacturers of rubber goods , asa rule , make evervth ing in the l ine of compounded rubber, hardor so ft , and in addition o ften are producers of gutta-perchagoods . In the United S tates , on the other hand , the tendencyhas been to specialize , and as a result the industry has divideditsel f natural ly into the following general lines z°mechanicalrubber goods ; ti res , pneumatic and solid ; molded work ; sun

dries , druggists’, surgica l , and stationers’ ; dental and stamp rubbers ; surface clothing ; carr iage cloth ; mackintoshes and proofing ; boots and shoes ; insulated wire ; hard rubber ; cements :notions ; plasters ; and reclaimed rubber.

The following brief description O f the manipulation o f rubber in these various l ines is given because there are superintendents and managers who are experts in one line but who maybe wholly un familiar with machinery and processes used in otherl ines .

M ECH A N I CA L RUBBER GOODS .

This line o f rubber manufacture , which is also known inEurope as technical rubber goods , embraces all the heavier com

356 DI VI S I ONS O F RUB B ER MANUF A CTURECOMPOUNDS F OR MECHAN I CAL GOODS .

- (Continued )CHEAP WATER HOSE COVER.

Coarse P araBest shoe rec laimWhite substituteBarytesLitharg eFine rag s

SulphurCotton seed oil

CHEAP WATER HOSE LI N I NG.

Coarse P araA ssamA fricanBest shoe reclaimWhite substituteZ inc oxideBarytesLitharg eWh itingBlue leadSulphurCotton seed oil

PERF ORATED MATS OR PACK I NG.

Coar se P araA ssamBest shoe reclaimWh ite substituteBlack substituteZ inc oxide

Sub l imed leadLitharg eLime

SulphurCotton seed o il

MATTI NG.

0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

B I LLI ARD CUSH I ON SF ine P araA ssamSub l imed leadBarytesLitharg eBlue leadSulphur

F I B ROUS GASKETS .F ine P araCoarse P araF ine rag sZ inc Ox ideBarytesLi tharg eSoapstoneWhitingSulphurBlue lead

RED SHEET PACKI N G.

Coarse P ar a

Red oxideA sbestineSulphurLimeCoconut oilBLACK SHEET PACK I N G.

Lopor iM echanical good s recla imZ inc oxideSubl imed leadA sbestine

0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

O O O O O O O O O O O O O O O O O O O

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

O O O O O O O O O O O O O O

O O OO

O O O O O O O O O O O O O O O

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

WH I TE TUB I N G,NO . I .F ine P ara

Coarse P ara

MACH I N E ROLL .Fine P araA f r ican tonguesZ inc oxideLitharg eP ar is whiteSulphurLampblackLime

WRI NGER ROLL,I N S IDE

A fr ican smal l bal lP ontianak 14 5Wh ite vulcani zed rubber dustCotton fiberWRI N GER ROLL, OUTS IDE .

Coarse P ara

Congo bal lZ inc oxideP ar is wh iteSulphurLime

B O O TS AND SHO ES 357

COMPOUNDS F OR MECHAN I CAL GOODS — (Continued )WH I TE TUB I N G

,NO .

—(Com) F I BER SOLE — (Com)Z inc oxide LithQP OHe

Sulphur Calc ined “1 3 8116 813

LimeSulphur

WH ITE SOLE .

WH ITE TUBI NG, N O 11 Coar se P ara

Ground.

waste rubber

Coarse P ara Z inc O x I dCZ inc oxide Black SubStl tUte

Wh iting Lime

Wh ite substitute SulphurSulphur

CHEAP WH I TE TUBI NG i

Coar se P ara

Mozamb iqueWhite substituteZ inc oxideWh iting

0 0 0 0 0 0

O O O O O O O O O O O O O O O O

O O O O O O O O O O O

BOOTS A ND SHOES .

The manufacture o f rubber boots and shoes , althoughapparently a S imple business , not only requi res large capital , buti s one that has often been overtaken by disaster. I t i s a matterof common knowledge that, gi ven the same compounds , the samemachinery, and the same ski lled workmen , no two mills are ablealways to turn out exactly the same grades o f goods . Qual ityis one ingredient that may or may not be added to the goods , nomatter how honest the endeavor. That there are reasons forth is , no one can doubt, and that the day will come when th isbranch of manufacture wi l l be an exact science is probably true .That , however, will entail a definite“ knowledge of rubber fromthe moment it firSt sees the light as creamy liquid exuding fromthe tree , through every event in its l i fe —in coagulation , transit ,storage , factory manipulation , compounding, calendering, cur

ing, its death in the service of man,and its later resurrection

in 'the process o f reclaiming. The need for exact in formationregarding the ingred ients added in the course ofwompound ing

RED SOLE .

Coar se P ara

Red inner tube.

rec laimGround r ed sol ingRed oxide o f i ronCalc ined magnes iaSulphurCoar se P araA uto tire reclaimGround waste rubber

M ineral rubberLitharg eZ inc oxideWhitingSulphur

358 DI VI S I ONS O F RUB B ER MA NUF A CTUREand their relation to each other, mechanically and chemically,has b een met by sc ientific study with marked improvement inquality of goods , machinery, and processes .

In the complete rubber shoe plant there are found , for initialequipment , washing rolls , m ixers , refining mil ls , and calenderssuch as most o f the other lines employ . In addition , there arespecial calenders

,with engraved rol ls for shoe-upper work ;

others , also , with engraved rol l s for sol ing :presses for moldingboot heels

,sole-cutting machines , and . O f course , vulcanizers . A S

thi s class o f goods is cured by what i s known as the “dry heat”—that is , by being confined in dry , hot air for several hoursit will readily be seen that it is a radically diff erent businessfrom mechanical rubber goods , for instance . These dry heatersare simp ly large, ventilated rooms , fitted with steam pipes forheating, lined with tin , double wal led to prevent radiation , intowhich hundreds of pairs of boots or shoes are run on ske letoncars to undergo the process of vulcanization . The manufactureof rubber footwear, in brief , there fore , consists in washing, drying, compounding and calendering the rubber and fabrics , thecutting of the calendered sheets into various shapes for cementing over lasts in the shapes desired , var ni shing, and the dryheat cure .

The usual method of curing rubber boots and shoes consistsin exposing them on racks in large

,dry heaters where the tem

pe rature of the air i s slowly raised by steam circulating in coilsbeneath the racks . Moisture and volatile products escape bynatural ventilation through openings in the roof of the heater.The air, a poor conductor of heat , ci rculates slowly and without pressure . The working conditions are there fore not underpo sitive control , and the time of vulcanization i s long, usuallyfrom eight to ten hours . The fact that the goods

,during vul

canizing , are not under pressure perm its the formation of blisterswherever included ai r or moisture is present . The loss f romthis cause is sometimes very considerable, and difficult to remedy . O ther defects o f the dry heater system of curing areirregularity o f cure

, due to faulty circulation of the ai r ; excess ive space required to handle the goods , because the cure isprotracted unduly, and . large cost of operation . Notwithstand

ing these de fects and drawbacks , the dry heater has remained

360 DI VI S I ONS O F RUB B ER MANUF A CTURE2 . Removal by vacuum of entrapped air and vulcanization

by pressure and heat appl ied by air, non-oxidizing, gases , orsteam.

3 . Compression of the goods by inflation or otherwise , ina mold heated internally or externally by steam ,for vulcani

zation.

BOOT A ND SHOE COMPOUNDS .

SHOE UP P ERs,H I GH GRADE .F ine P ara

Coarse P araSulphurLitharg eLampblackCoal tar 10 .0

Wh itingSHOE UPPERS

,MEDI UM GRADE .Fine P ara

Coar se P ara

S li oe rec laimSulphur

Coal tarWhitingBOOT UP P ERs

,H I GH GRADE .F ine P ara

Coarse P araSulphurLithar g eLampblackCoal tarWhitingBOOT UPPERS

,MEDI UM GRADE .Fine P ara

Coarse P araShoe rec laimSulphur 2 .0

Litharg eWhitingCoal tar 12 .0

SHOE SOLI NG,H I GH GRADE .F ine P ara 10 .0

Central Amer ican 12 0

Shoe r eclaimSulphurLitharg eLampb lackA sphaltum 8 0Wh itingSHOE SOLI N G

,CHEAP GRADE .

Coar se P araShoe r eclaimSulphurLitharg e

SHO E SOLI N G,CHEAP GRADECon. )


0 0 0 0 0

O O O O O O O O O O O O O O O O O

o o o o o o o o o o o o o o o o o o o

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0


BOOT A ND SHO E CEMENT.Fine P araSulphurLitharg eDissolve in naphtha to cous isteney suitable for brush work.

A sphaltumWh it ing 35.0

BOOT SOLI N G,H I GH GRADE .

Coar se P araSulphurLitharg eLampb lackA sphaltum\VhitingBOOT HEELS

,H I GH GRADE .F ine P ara 5

Coar se P ara 1

?A f r ican g radesReclaim 20

EMFFFF

o

oo

c

o

o

o

o

bbo

c

o

o

Sulphur 1

Litharg e 12A sphaltum 6Wh iting 36 .BOOT HEELS

,MEDI UM GRADE .

A frican g radeRec laimSulphurLithargeA sphaltumWh itingBLACK TEN N I S SOLI NGFine P araCoar se P araWh it ingLitharg eLampb lackSulphurP laster of P ar isBOOT A ND SHOE F RI CTI ON .F ine P ara 15 .0

A f r ican g radesSulphurLitharg e 15.0

DRUGGI STS ’AND S TA TI ONERS

’SUNDRIES 361

RUBBER- SHOE VARN I SH .

Calcutta linseed oi l i s p laced in an iron kettl e over ananthracite fire in a deep fireplace , to carry away the fumes .To the oil are added small proport ions of litharge , sulphurand j apan drier. The contents o f the kettle are Slowly boiledfor some hours unti l we l l th ickened . The l iquid require s constant attention and frequent stirring to prevent ignit ion orrai sing over the top of the kettl e . When judged suffi cientlyboi led , the kettle i s removed out of doors and when wel lcooled the contents are thinned for us e to about 50 degreesB eaume with turpentine and naph tha . Care must b e exerc is ed that the addition of these volati l e l iquids b e not madeunder conditions permitt ing thei r vapors to find their wayto the fire in the varnish house

,or d i sastrous consequences

wil l result . A s imple method of preventing thi s i s to placeSand bags at the bottoms of the doors of the varnish boilingroom .

DRUGGI STS’, STATIO NERS’A ND SURGICAL SUNDRIE S .

TH I S part of the rubber business entails more skill fulmanipulat ion and more finesse in manufacture than almostany other line . A n atomizer bulb

,for example , must be

graceful in Shape , with delicately smooth surface , of goodcolor , and ei ther of the non-bloom ing variety or so near itthat the sulphurous effloresc ence wil l be so s light as to passunnoticed

,while in mechanical goods a length of garden 'hose

may be of an y color, may b loom until crusted with sulphurcrystals

,but if it “s tands up to work , i t i s the b est , and i s

b eautiful in the eyes of the trade .The question of colored rubber i s one that has interested

th i s b ranch of the busines s from i t s inception . I n none otheri s so much wh ite rubb er made and , incidental ly , none othersget such good effects . Th i s ins is tence by customers on wh itegoods and by physicians on black , containing no trace of lead ,has entail ed a deal of trouble upon thi s trade , for the manufacturers unti l recently could not go into the open marketand buy a high grade of wh i te recovered rubb er , while ofb lack there is

‘

ever an ample supply , and for b lack goods tosui t the phy sician the manufacturer i s forced to substitute a

362 DI VI S I ON S O F RUB B ER MA NUF A CTUREdry

,bulky vegetable b lack for oxide of lead or white lead , and

then not get as good a result .The mach inery used i s very simi lar to the equipment ofa mechanical goods factory , but the scale i s smaller . Washers ,

g rinders ,ca l enders

,tub ing mach ines , steam vulcanizers , and

smal l s team presses are the mach ines used . Specia l machinesare emp loy ed in certain part s o f the work , but their use i sl im ited to a few factories .

The feature in thi s trade which stands out most di stinctly from other rubber lines is , perhaps , the manufacture ofho l low work

,as atom iz ers

,syringes , breast -pumps , and a host

of oth er ba l l s and bulb s . The parts for thes e are cut fromsheets of compounded rubber

,cemented together at the edges ,

inflated to the genera l shaps of the mold and cured in opensteam heat . I n order that the bal l may fi l l the mold perfectlyduring the cure , a few drops of water or a l i ttle ammonia areput ins ide of i t wh ich , vaporizing under the heat , developspres sure enough to perfectly shape i t and add to it s outersurface the fini sh found on the inner surface of the mold .

The difficul ti es that manufacturers in th i s l ine experiencein mak ing perfect goods are legion

,as they are in other l ines .

They are added to by the fact that the trade , as already indicated , demands articl es of b eauty from a gum that was designed for uti l ity solely . A trace of b lack in a white compound may spoil hundreds of dollars’ worth of goods , nor cansuch trace b e rubbed off

,scoured out, or eradicated , after

vulcanization . Hence , white , black , red and other colors mustbe mixed on separate mi l ls , and the trimmings and scraps keptsedulously apart .

P ure gum— that i s , rubb er compounded on ly with sulphuror some other vulcaniz ing agent— i s al so largely produced inth i s l ine . F or example , i t makes .what i s known as denta ldam , the pure sheet used by denti sts . Thi s i s general ly asulphur compound cured in open steam . Certain manufac

turers,however

,practice the vapor cure with good Succes s in

mak ing these goods . Th i s cure gives a beautiful fini sh,but

if not done with great sk i l l i t may b e disastrous to both theworkman and the goods .

364 DI VI S I ONS O F RUB B ER MANUF A CTURECOMPOUNDS F OR DRUGGI STS’

,STATI ON ERS’ A ND SURGI CAL

SUNDRI E s . Continued )SPO N GE RUBBER

,N O . I I . N O N - BLO OM I NG BLACK

Coarse P araF

'

PWh ite substitute m ” a

Wh iting Litharg egulphur

eres inP ine oil Lampb lackAmmonium carbonate Lead hyposulph ite

MA CK INTO SHES , P RO O F ING A ND CA RRIAGE CLOTH .

TH I S busines s may be handled,in a measure

,as the

mechanical goods bus ines s is ; that i s , the gum s may b e mixedby heat on ordinary mixers , and then spread by calenders onthe fab rics wh ich give the artic l es their strength . Thi s i s themanner in whi ch rubb er surface clothing i s run . The machinery i s s imp le

,since

,in c loth ing , the parts are cemented

together and cured in dry heat . I n carriage cloth s,after ca l

ender ing , the goods are grained on embossing ro l l s , varnished ,and run into a dry heat .

The mackintosh and proofing bus ines s , however , i s somewhat a departure from thi s . Here the gum ,

after m ixing dry ,i s usual ly put in churns with a cheap solvent and reduced toa so lution . I t i s then appl i ed to the cloth with a knifespreader .

F or doub le- texture work , a simple doub l ing machineb rings two surfaces together. A portion of the bus ines s thathas divided itself from the res t i s what i s known as proofingfor the trade . Here manufacturers simply coat the cloth andsell it to others

,who make it up into garments , or anythingin fab ric or rubb er for wh ich there may b e a cal l . The mack

intosh manufacturer to-day is not only familiar with a greatvariety of rubber gums and ingredients used in compounding ,but i s al so an expert in fabrics

,as h is bus ines s i s real ly

closely akin to the tailoring busines s .CLOTH I N G A ND CARRI AGE CLOTH COMPOUNDS .

DULL F I N I SH CLOTH I NG . DULL F I N I SH HE AVY COATS .F ine P ara Fine P ara

Reclaim Recla imWh iting P ar is wh iteLitharg e 10 50 Lampblack 3 0

Coal tar Litharg eSulphur SulphurP alm oil Black substituteRos in Coal tar

CLOTHING COM P OUNDS,E TC.

CLOTH I N G A ND CARRI AGE CLOTHWH ITE SURF ACE CLOTH I N GFine P araWh ite reclaimed

Wh itingZ inc oxideCalcined magnes iaSulphur

DOUBLE TEXTURE .Fine P araP ar i s wh iteLitharg eZ inc oxideSulphur

CHEAP DOUBLE TEXTURE .

Lump A f r ican flakeA ccra buttonsBlack substituteCheap shoe reclaimGi lder s’ wh itingLitharg eCoal tarSulphurP ontianakCalc ined magnes iaRos in

GO SSAMER F I N I SH .Fine P araP ar is wh iteLampb lackShel lacSulphur

TRAN SPARENT GO SSAMER .Fine P araCentral Amer icanShel lacSubstitute 12 0

SulphurS I NGLE TEXTURE CLOTH I N G.F ine P araZ inc oxide

'Litharg eLampb lackSulphurP alm oil

CEMEN T F OR HEAVY COATSF ine P araWh itingLitharg eLampb lackSulphur

Ros in 1 0

Coal tar l 0CEME NT F OR COATS .

Central Amer icanA f r ican flake


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


O O O O O O O O O O O O O O O O O O


0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

o o o o o o o o o o o o o o o

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

365

COMPOUNDS — (Continued )CEMENT F OR COATSWh iting 3 .0

Litharg e .5Rec laim 3 .0Sulphur 5

VULCAN I ZED GOSSAMERFine P araWh itingLampblackLitharg eCoal tarSulphur

CHE A P GO SSAMER .

wo

PROO F I NG.

A fr ican flakeA ccra buttonsShoe r eclaimWh ite substituteLitharg eCalc ined magnes iaP ar is wh iteSulphurZ inc oxideP alm O il

CHE A P P ROO F I NG.

ReclaimP ontianakWh itingBlack substituteLitharg eSulphurCoal tar

CARRI AGE CLOTH N O I .

Coarse P araRec laimWh itingLitharg eLampblackSulphurCoal tarCARRI AGE CLOTH N O I

Coarse P ara

SubstituteReclaimP ar is whiteLitharg eLampb lackTar 9

M ineral rubberSulphur

F"

\l

o

s

s

e

e

rs

382

888

88

8

88

“Ch

I

7

32

0

74

34

03

33

83

88

366 DI VI S I ONS O F RUB B ER MANUF A CTURETIRE S .

A LTHOUGH the ti re business seemed at first to be a naturalpart of the mechanical rubber goods bus iness , i t real ly provedit se lf

,later

,to be a bus iness whol ly di stinct from it . Even

the large manufacturers of mechanical goods who began tiremaking on a cons iderab le scale , keep thi s part of their busines s distinct from other branches as a rul e , running it as anenti re ly separate department . A large bus iness i s done inpneumatic t i res for b icycles and motor cycles , but i t i s muchsurpassed b y the production of pneumatic automobil e t ires .The knowledge gained through the manufacture of pneumaticb icy cle tires (which , by the way , was one of the hardest probl ems that the rubber trade ever solved ) has proved wonderful ly eff ective in developing the sk i l l neces sary to make thi sheavier and more important artic le . Thi s ti re , l ike the b icycletire , i s bui lt up of fr ictioned duck , with an outer coating ofh igh-grade rubb er careful ly vulcaniz ed . Wh i le a variety ofcompounds is used in its make-up,

it is true that no manufacturer is able to sell a very low grade of good s , even of unguaranteed quality, because the li fe o f the ti re is so important, andthe purchaser so desirous for a good article . Cheapening toany great extent is not feasible , particularly in tires sold unde rmileage guarantee . A n adjunct of this business is the manufacture of inner tubes , which has assumed very large proportions .

The general machinery used in making tires i s the samethat i s used in the work of preparing rubber in other lines .There are two general classes of tires manufactured

,however

Those that are molded,and those that are made in such a way

that they can b e wrapped for the proces s of vulcanization .W rapped goods

, O f course , are cured in an open heat . I n theone case the tires are cured in presses , sometimes in nest s ofmolds , and sometimes in vulcanizers . Various ingenious andvaluabl e processes and special machines have b een invented ,and are now in us e in this l ine . A n industry that has grownup in connection with the ti re business , and has increased thepractica l knowledge of the uses of rubber wonderfully, i s thatof ti re repairing, which is carried on in many places and to animportant extent outside of the rubber factories proper.

368 DI VI S I ONS O F RUB B ER MANUF A CTURETI RE COMPOUNDS . Continued )B I CYCLE T IRE— I N N ER TUBE . SOLID CARRI AGE TIRE .

F ine P ara Coarse P araZ inc oxide Upper CongoBlue lead Z inc oxideLitharg e Subl imed leadP ar is wh ite Litharg e

Ground sol id tireBest r eclaimSulphur

B I CYCLE T IRE F RI CTI O N

Fine P ara CA B TI RE .

A ccra P araCameroons Z inc oxideLitharg e Infusor ial earthl

.

e.

SulphurWhi ting LithargeSulphurBA BY CARRIAGE T IRE .

SO L ID TRUCK TI RE .

Congo Fine P araP ontianak A uto tire rec laimFloating reclaim Z inc oxideCheap reclaim Li tharg eSubstitute 8 5 Sulphur

Calc ined magnes iaBarytes M ineral rubberSulphur 4 . A sbestine

INSULATEDWIRE .

TH E manufacture of insulated wire , either wi th india rubber compound or gutta-percha insulation , i s a l ine that i smore distinct ly apart from other portions of the rubb erbusiness than almost any other . F or gutta -percha , the general mach inery used is described in the chapter on that gum .

Where india rubb er i s used , the crude gum i s treated in thesame way as in m echanical goods . I t may be forced over thewires by tub ing machines , or welded together in strips thatare run b etween grooved rol ls .

B raiding mach ines are al so a part of the outfit for weav

ing the protective covering , and the wire is usual ly wound onhuge drum s and vulcaniz ed in open s team heat or in pansunder water in open steam . P oli sh ing mach ines

,testing

machines , and various mechanical contrivances are , also , apart of this equipment . The l ine of compounds used is oneadapted almost whol ly to th i s industry , and embraces a greatvariety of ingredients and gum s that are treated specifica l ly ,under their spec ial heads , el sewhere in thi s book.

INSULA TI ON COMP OUNDS 369

WH ITE CORE .F ine P araMagnes ia

Litharg eWh iting

B LA CK CORE ,Fine P araMagnes i a

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0

Litharg e WH I TE ELECTRI C TAPEWhi ting Borneo

RED ANTI MO N Y CORE . A f r ican flakeCoar se P ara Balsam fir

Soapstone VYhiting .

Golden antimony Z inc ox i deWh ite substitute

RED CORE .

Coarse P araZ inc oxide 1

I ron oxideWhite substitute 1\VhitingUNVULCA N I ZI NG I N SULATI O .

Coarse P ara

.8

2:

0

0

0

°

C

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

8Q

mm

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

b.)

3 .

3 .

3 .$

00

00

3Rec laim (not devulcanized ) 3

GRAPH ITE I N SULATIO N .

Coarse P ara

Graph iteSulphur

I—I ARO ‘Kf I RE COVERI NG.

o o o o o o o o o o o o o o o o

Madag asca r0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

SulphurSO F T COVERI NG

,N O . I

Madagascar

ga

l

la

fia F RI CTI O N TAPE

,N O . I I

u p urCoarse P ara

SO F T COVERI N G,N O . I I . A f r ican smal l bal l

Central Amer i can A f r ican flakeSS Z inc oxide

.0 Wh iting0

0

0 0 0 0 0 0 0 0 0 0 0 0 0

SulphurCotton seed oi l

MOLDED GO ODS MANUFA CTURE .

A PART of the rubb er business that b elongs either to them echanical or to the druggist s’ sundries l ine has

,during the

past few years , detached itsel f f rom the rest , so that to-daymany large factori es are run s imply in producing small mold

I N SULATI ON COMPOUNDS .

\VI I I TE ELECTR I C TAPEA f r ican soft bal lCameroonsA fr ican flakeWh itingZ inc oxideRos in

BLACK ELECTR I C TAPEA ssamA f r ican flakeP ontianakBarytesZ inc oxideLampblackTurpentine , crude

F RI CTI O N TAPE,NO . IF ine P ara“

A f r ican smal l bal lA frican flakeBest shoe reclaimZ inc oxideBarytesLitharg e“mitingSub l imed lead

370 DI VI S I ONS O F RUB B ER MANUF A CTUREwork . They have the usual equipment of rubb er machinery

,

specia l app l iances “

for fil l ing and emptying mo lds,and the

usual aggregation of hard and soft metal molds that run

into thousands of do l lars in a short time . The extent towh ich th i s busines s i s carri ed may b e imagined when i t i sknown that one company runs 300 presses on thi s work

,and

many have from 20 to 50 i n constant s erv1ce . When i t i srememb ered that very rare ly are two compounds exactlya l ike , i t wi l l b e s een that , in th i s l ine also , the expert compounder has a wide field for thought and experiment .

COMPOUNDS F OR MOLDED GOODS .

TOUGH M EDI UM HARD VALVE . SMALL ARTI CLES , N O . I I I .Fine P ara (Con )BarytesLitharg e 9 .75P lumbag o 8 .00Wh iting 16 .00

Blue lead 6 . 50 SPRI NGS .

Sulphur Coar se P ara

SO F T PUMP VALVE .

A ffl ca“

F ine P ara Ground rubber waste

Coar se P araLi tharg e

BarytesLitharg eBlue leadLamblackSulphur

SMALL ARTI CLES,N O . I .

Coar se P araBlue leadWh itingInfusor ial earth

4 252 00

SMALL ARTI CLE S ,N O . 11 .

P enangBlack substituteZ inc‘

oxide532221

“

L

LA RGE ARTI CLESopor rSulphur Black substitute

SMA LL ARTI CLE S , N O . I I I Ground sol id ti resCoarse P ara BarytesReclaim Litharg eBarytes Lime

Litharg e SulphurBlue lead P alm O il

Lime

SulphurRED SO F T PUMP VALVEF ine P ara 3

Coar se P ara 3

A ntimony golden sulph ide ’

1

Sulphur N

o

o

c

O

O

men

MEDI UM PUMP VALVEFine P araCoar se P ara

A f r ican th imb lesBarytesLitharg eWh itingSoapstoneBlue leadSulphur

372 DI VI S I ONS O F RUB B ER .MANUF A CTUREHARD RUBBER CoM P OUNDs . Continued )RODS . RED MOLDED— (Com )

P in MadagascarVermi l ion

Conl

gObal l Ch ina c layBorneo Sulphur:Hard rubber dust P alm 0 11

SulphurCotton seed oil SEM I -HARD.

BeeswaxLime

SYRI N GE P I PES .

Fine P araSulphurHard rubber dust

RED IVI OLDED. CO IVI B S .

Fine P ara F ine P araRed oxide Sulphur

CEMENTS .

MAN Y rubber factori es are run wholly on this l ine of

work,'

the gums b eing mixed as in a general rubber bus iness ,put into solution in churns , and sold by the barrel for aninfinite variety of purposes . Hundreds of diff erent formulasare in use for cements intended for general and specific purposes . The l eather shoe bus iness , for instance , call s for a dozenor more special cements . The bicycl e busines s has need for agreat many grades of what are known as t ire cements . Sticki

nes s . waterproof quali ti es , durab i li ty , and cheapnes s in theirgoods are sought by all cement manufacturers , and , in orderto secure these qual i t ies , they demand ski ll in compoundingin no way inferior to that shown in other lines of rubberwork .

CEMENTPURE-

GUM CEMENT.F ine P ara d is solved in benzol ornaphtha.

WH ITE (CURI NG) .Fine P ara 20 poundsZ inc oxide 12 pound s

Sulphur 2 pounds

Naphtha 25 gal lonsYELLOW (CURI NG) .Fine P ara 20 pound s

Litharg eZ inc oxide 8 pound s

Sulphur 2 pounds

Naphtha 25 gal lons

COMPOUNDS .

LEATHER SOLE CHAN N EL,

N O . I .Fine P ara (washed ) 30 pounds

Ros in '5 pound sNaphtha 40 gal lons

,LEATHER SOLE CHAN NEL,

N O . I I .Fine P ara (washed ) 10 pound s

Ros in 5 pounds40 gal lonsHARD-RUBBER CEMENT.Fine P ara 30 pounds

Sulphur 10 pounds

Naphtha 12 gal lons

DEN TA L AND STAM P GUM COM P OUNDS 373

CEMEN T COMPOUNDS — (Continued )LE ATH ER WELTI NG.F ine P ara 10 pounds

Sulphur 5 ounces

Naphtha 10 g al lonsLEATHER SOLE-LAYI NG.

Lagos buttons or str ips 10 poundsP ontianak 5 pound sNaphtha 20 gal lonsLEATHER BELTI NG

,NO . 1 .

Carbon b isulph ide 20 pounds

O il of turpentine 2 pounds

Gutta-

percha suffi c ient to form a

DAVY’S UN IVERSAL .Outta-

percha.

Common pitch .

Equal parts of each me lted to

g ether .

F I N E DI PPED WORK .

F ine P ara 2 pounds

Carbon bisulph ide 60 pound sA bsolute alcohol 4 pound s

paste. MARI N E GLUE,F REN CH .

LEATHER BELTI N G, N O . 11 . Dissolve 10 pounds caoutchouc

Caoutchouc 6 pounds in naphtha and add 20 pounds

Shel lac 4 pound s she l lac . Melt unti l m ixed and

Carbon b isulph ide 40 pound s pour wh i le hot on metal plates toTurpentine 4 pounds cool .

DENTAL A ND STAM P GUM

TH E manufacture of unvulcanized g ums ’

for the use ofdentists and rubberstamp manufacturers is an industry apartfrom other lines

,and one that has as sumed large proportions .

The rubb er i s compounded and sold by the manufacturer, andcured and finished by the dentist or rubberstamp manufacturer . I n stamp work the rubber i s compounded for softrubber and many hundreds o f tons are sold during the year,while , of course , the dental rubber i s so mixed that under thecure i t b ecomes vulcanite of the color desired . The machinery for this work consi sts chieflv O f washers , m ixers , andca l enders .

DENTAL A ND STAMP GUM COMPOUNDS .

DE NTAL—{I IGH T P I N K . DE NTAL— BLACK VVE IGH TED.F ine P araLithopone (g reen .0 15 5Lac sulphurLime

P ale vermil ionUltramar ine b lue Trace

DENTAL— BLACK PALATE .Fine P ara STAMP GUM ’ N O ' I '

Lac sulphurLampblackLime

DE NTA L— RED PALATE .Fine P araLac sulphurDark verm i l ionLime

O O O O O O O O O O O O O O O O O O O O O O

374 DI VI S I ONS O F RUB B ER MANUF A CTUREDE N TAL A ND STAMP GUM COMPOUNDS — (Continued )STAMP GUM ,

N O . I I . STAMP GUM,N O . I I I .

F ine P ara 20 -0

Coarse P ara Litharg e\Vhiting White leadZinc ox ide mm.

Litharg e Barytes.

IISulphur Sulphur

NO TIONS .

TH I S department of the rubber business , the importanceo f which is not general ly appreciated

,i s that which takes in

such Work as waterproof dres s b indings,dress shields , ch i l

dren’s aprons , diapers , etc . S evera l large factorie s manufac

ture thes e goods,mixing their rubber by the usual proces ses ,

coating it on calenders , and having specia l machines for forming and curing the goods in thei r special shapes . I n themanufacture of dress shields the vapor cure i s o ften pract iced very succes sful ly . The rubber manufacturers of thi sc lass are not by any means inexpert compounders . Theyhave al so

,perhaps

,gone as far as any in deodori zing rubber

goods , so that the smell of the gum or any compoundinging redients i s wholly done away with .N OTI O N -TRADE COMPOUNDS .

DRESS SH I ELDS . VVI I ITE B A TTI I NG CA P

Fine P ara Fine P araZl

7

nG oxi de Z inc oxideWh ite substi tute

Sul hurLitharg e p

.

Sulphur Calcmed magnes ia

BLUE SH EETI NG— VAPORP

CURE ’

5 5CRIM SO N BATH I NG CA P .Fine ara 6 . Fine P araZ i nc Od e

Ultramar ine b lue S O IUbIe 0 11 red

“rH I TE S I 'I EETI N G VA P ORsulphur

CURE Calcmed magnesi a

F ine P araZ inc oxideN URSERY SHEETI NG . BLUE BATH I NG CA PFine P ara F ine P ara

gizgtigil de

Solub le O il blueSulphurP alm oil Calc ined magnes ia

CHA P TER XX .

GUTTA - P ERCHA— ITS SOURCES , P RO P ERTI ES ,

MA N I P ULATIO N A ND P RINCI P A L USESTY P ICA L COM P OUNDS— B ALATA .

GUTTA-PERCHA , wh ich was introduced into Europe fromS ingapore in 1843 , was for a whi l e confounded with indiarubber, from which i t differs in some very important particulars . I t becomes soft and p lastic on immers ion in hot water ,retaining the shape then given it on cooling

,whereupon it

becomes hard , but not brittle , l ike other gums . India rubber ,on the other hand , does not soften in hot water , and retains itsoriginal e lasticity and strength unimpaired . The water

,as

such , exerci ses no softening action on gutta-percha , the eff ectb eing purely one of temperature , wh ich may equally well b eproduced by hot ai r , onl y somewhat more slow ly . The degreeof heat requi red depends upon the qual ity of the material , buteven the hardest kinds b ecome p lastic above 150 degrees F .

H eated in air cons iderably above the boi l ing point of water,gutta-percha decomposes and final ly igni tes , burning with alum inous smoky flame and emitt ing a pungent odor resemblingthat from burning rubb er. I f heated in a vacuum

,gaseous

and l iquid products are obtained simi lar to those result ingfrom the dist i l lation of rubber . The l iquid which disti l ls overcons is ts chiefly of hydrocarb ons of the terpene seri es , whichform an excel lent solvent for caoutchouc . The two mostimportant are isoprene and caoutchine

,which are identical with

the l iquids by the same names obtained from india rubber .S ince these products can al so be ob tained from other sources ,Dr . Eugene O bach and others have O bserved that they mayyet form a stepping -stone in the synthetica l production ofindia rubber and gutta-percha from the lower terpenes .

A curious phys ical characteri s tic of gutta-percha is thatwhen it has been softened in water

,although it is so plastic

that it wil l reproduce the most del icate impress ions , i t wi l lwithstand b lows from hammers or may b e thrown against

COMP ONENTS O F GUTTA -P ERCHA 377

stone without b eing marred . The reason is that i t containsa large amount of air . B y subj ecting gutta-percha to a vacuum

,a large amount of air i s withdrawn from the gum , and

i t loses i ts property of hardening on cooling , its substancebeing like a tough , greasy leather.

Nowhere on the glob e have genuine gutta-percha treesb een found outs ide of an area embracing portions of the M alaypeninsula

,B orneo , Sumatra , and adj acent i s lands . These trees

belong to the natural order S apotaceaz; the principal genera andspecies will b e noted further on .P ure gutta i s insoluble i n ether and ligh t petroleum spirit

at ordinary temperatures,whereas both albane and fluavile

dis solve readily in them . Gutta posses ses all the valuab lequali ties O f gutta-percha , but in a much enhanced degree ; i tb ecomes soft and plastic on heating

,and hard and tenacious

on cooling, without being in the least brittle . B ut the resinsthemselves at ordinary temperatures are either soft or qui tefriabl e . I t i s , therefore , gutta wh ich forms the useful constituent of gutta-percha , and the res ins are only acces sorycomponents , which , although admiss ib le , and perhaps evendes irab le in a comparatively smal l amount

,yet have a de

c ided ly detrimental eff ect when they preponderate . H ence ,in order to determine the technical value of a sample of guttapercha

,i t i s neces sary first to learn the relative proportion

or ratio between gutta and resins . There must also be takeninto account the water enclosed in the mass , and the coarse impurities—wood fibers

,bark, sand , etc . —which are described as

dir t. These components represent the loss or waste to the manufacturer.While the relative proportion of gutta and resins forms an

important criterion for estimating the commercial value o f asample , it i s not in itsel f sufficient . A lthough the analysis oftwo different specimens may give the same result , the physicaland mechanical properties , and , most important of all , the durabil ity, may differ widely, owing to a difference in their molecular constitution . It will thus be seen that there are guttas andguttas . In addition to the qual itative analysis , it is necessary toscrutinize the gutta itsel f , which requires much judgment andexperience . A naly ses have been made of specimens wh ich con

378 GUTTA -P ERCHArained eight times as much gutta as resin ; others containedabout an equal amount of both , and in still others the amount ofresin was three times that of gutta . Samples in which the percentage of resin reaches that of gutta , or surpass it , are of ad ecided ly in ferior description . These diff erences are due doubtless to the fact that the gutta-percha of commerce is derivedfrom trees o f various species , and also in part to the treatmentwhich the gum receives at the hands of the gatherers , who arepected of mixing the product of diff erent trees , to say noth

ing of adulterations of a more debasing character.The commercial classification o f gutta—percha is less sati s

factory than that O f india rubber, since no standards have become fixed in the markets . While P ara rubber

,for instance ,

may be bought and sold by means of established designations ,“I slands fine ,” “Upriver fine ,” and the like , no such practiceexists with regard to gutta-percha . S ince all transactions in thelatter are based upon samples

,trade names and brands are little

considered . However , “Macassar, and “

B andj ermassin ,” whichare the names of districts producing gutta-percha , were formerly used to indicate the highest quality, while “Sumatra sortswere supposed to be less valuable , and “

B orneo the lowest o fa l l . I n a sense these designations have become merely commerc ial

,no longer aff ording any indication of the origin of the

gutta-percha . A t the same time , “Macassars” and “B andjer

massins”m ight vary with every new arrival , so that one was

not certain , in buying one of the so rts named , to obtain partienlar ly good gutta-percha ; it might have been the very opposite .

Innumerable sorts appear in the S ingapore market— whichis the center of the gutta-percha trade ; but Dr . O bach selectedtwelve of the principal b rands as typical O f all the rest , anddivided them into four groups , for convenience in comparison ,the best being named first . They are as follows , the designations being derived either from the countries of their origin orf rom the places of export :

1. P ahang— from the M alay peninsula.

I . s

, 2 . Bulongan red— f rom Macassar, Borneo.

I 3 . Bandi er r ed— from Bandj ermass in, South Borneo4. Bag an g ool ie soondie— from Borneo.

Gool i e r ed soond ie— f rom Serapong , Borneo .

O. S erapong g oo l i e soond i e— f rom S erapong , Borneo .

380 GUTTA -P ERCHAreceptacles p laced under the tree . The col l ected m i lk is thengently boiled, either by itsel f or with the addition of water . Thema te rial obtained without the use O f water is called a goalie, theother a gutta; but the two k inds are Often mixed together. The

gool ie is more compact than the gutta , and has a dough- l ikesmell . The word soondie is derived from the Malay term“gutta- sundek ,” which is applied to the product of trees of theP ay ew species already re ferred to .

The processes employed by manufacturers for c leaning rawgutta-percha are either mechanical or ”

chemical . Those of thefirst class will first be considered . Generally speaking, the rawgutta-percha is either first cut up in a slicing machine and thensoftened in hot water

,or the lumps are placed directly in hot

water and the soft materia l trans ferred to the washing machine .There it i s washed with hot water for a longer or shorter time ,and then passed through a strainer . Next, as a rule , it is washedonce more , then put into a kneading or masticating machine , toconsolidate it and remove the mechanically enclosed water, andfinally i t goes to the roll ing mi l l , to be made into sheets .

The slicing machine or chopper now used is pretty much thesame as that proposed by Charles Hancock

,of England , in his

patent (NO . O .L. ) of 1847, except that it i s providedwith a greater numbe r o f fluted and serrated knives , instead ofonly three plain ones , fixed in the slots o f a heavy iron disc . Theb locks of gutta-percha are packed into a trough and then forcedagainst the rotating disc , the knives in which cut the materialinto thin sl ices .

The wash ing mach ine consi st s of an iron ro l l er of starshaped section

,enclosed in a cy l indrical shell provided with

one or two proj ections,or rib s , against which the gutta-percha

is forced in going around . The cylindrical shell is enclosedin a large i ron case

,fil led with water

,wh ich i s heated by

means of di rect s team . The dirt , as it i s washed off,fa l l s

through the lower part of the cylindrical shel l into the outercas e , whence it i s drawn off periodica l ly . Th i s machine i sdeveloped from that ~desc ribed in the Engl i sh patent of R . A .

B rooman (NO . O .

The gutta-percha leaves the washing mach ine in a plas ticstate and passes to the straining mach ine— a strong iron cy l

ME CHAN I CAL TREA TMENT 381

inder with a perforated bottom , On wh ich a number of di scsof fine wire g auze have been placed . I t has a pi ston whichis driven home by hydraul ic power, at a pres sure of topounds per square inch , squeez ing the soft gutta through

the meshes of the gauz e .The kneading mach ine or masticator resemb l es the

washer,except that the rol ler i s smaller in diameter

,and the

fluting s are more numerous and not so deep . The guttapercha i s kept hot during mastication and the water escapesin the form of steam through openings at the top .

The m ixing machine , introduced by P aul P fe iderer , i ssimilar to that used in the india rubber, l inol eum ,

and othersimilar industries . I t i s provided with pecul iarly shapedb lades

,working agains t one another . The machine i s used

for mixing the various sorts of gutta-percha , in order to .obtaina material of requisite properties , and also for blendinggutta-percha with pigment s or other ingredients . The roll scan be heated by steam ,

but heat i s developed by the kneadingproces s its elf , and care must be taken not to overheat thematerial

The gutta-percha is next rol led into sheets,usually b e

tween and inch , and cut into lengths of 5 or 6 feet ,and stacked away for use . The roll ing machine takes thematerial from the m ixer and squeezes i t between parallelrol lers , running it back and forth unti l i t i s cool and hardenough for cutting up .

The - average percentages of waste,shown by numerous

anal y ses of the twelve brands of gutta~ percha catalogued ona preceding page , are about a s fol lowsP ahang 34 Bulong an wh iteBulongan r ed 35 Wh ite m ixedB and jer red 44 Band ier wh iteBagan gool ie soondie 32 Sarawak mixedGool ie red soond ie 27 P adang rebo i ledSe rapong soond ie 36 Banca rebo i led

The diff erence in the quali ty of various b rands of guttapercha , measured by the relative proport ions of gutta andresin , has already been mentioned . O f the sort s mentionedabove

,

“B anca reboiled” shows a comparatively small los s in

cleaning, but i t i s the least valuab l e on the l i st , being low

382 GUTTA -P ERCHAi n gutta , whereas P ahang, though l osing more in the cleaning proces s

,i s by far the most Valuab l e sort in the market ,

b ecause so rich in gutta . Gutta-percha imported in recenty ears loses more in cl eaning than formerly ; Dr . O bach ,

in1898,estimated the los s as almost twice as great as formerly .The chemical washing proces s was suggested by Charles

Hancock , i n an English patent , in 1846 . He steeped raw guttapercha

, cut into sma l l pieces,in a solut ion of caustic alkal i

or ch loride of l ime,to neutra l ize the acidity and remove any

unpl easant odor . H i s experiments showed that the alkalinetreatment not only reduced the percentage of dirt— that is , i twas better cl eaned than by the mechanical process— but les sened the capacity of the gutta-percha for retaining mechani

cal ly enclosed water . B ut the treatment with chemicalsrequires great care and judgment , and thorough subsequentwashing with water ; otherwise the material wil l b e renderedperi shab le .Chemicals were al so used by O bach for hardening guttapercha . The real ly valuable const ituent of gutta-percha being

the gutta , the more a samp l e contain s of the latter, the betteri t i s , provided the gutta it self i s of a good description . F or

certain purposes i t i s advantageous to improve the hardnessand other mechanical propertie s of gutta-percha , and thi s canbe done by extracting the res in with a suitab l e solvent , whichleaves the gutta it self intact . The raw gutta-percha i s firstchopped and thrown on drying platform s gently heated fromb elow by steam pipes . O r the pieces may be thrown intoa rotating drum heated by currents of warm air . They thengo to a s erie s of tanks in which petroleum spirit i s used asa solvent for the res in . The spirit b ecomes charged with theresinous matters

,and the resulting solution is di sti lled off

,

after which the material remaining i s masticated as in thecase of any other gutta-percha . A specimen treated by thi sproces s wil l remain quite hard under a temperature whichwil l render other specimens soft and plastic . O ther liquidsmay also be used , as ether, and a saturated solution of carbondisulphide in alcohol .

I nstead of removing impurities from gutta-percha bywashing i t either with water or an alkal i , th i s can be done

384 GUTTA -P ERCHAC

constitution of the resin and also of the gutta . The softeningtemperature of gutta-percha depends ent irely upon the ratioof gutta and resin . A specimen of which 60 per cent . wasres in was softened at the temperature of 48 degrees C . to thesame extent as another specimen , containing only 2% percent . of resin , for which a temperature of 55 degrees C . wasrequired . The t ime for the material to become hard again

,

after having previously been softened in hot water,depends

in a l ike degree upon the proport ion of gutta and res in . B ut

the principa l mechanical property of gutta-percha with whichthe manufacturer has to deal i s the tensi le streng th . A specimen having 45 per cent . of gutta and 55 per cent . of res inwi l l break under pres sure of 770 pounds to the square inch ,whereas for another specimen

,after most of the resin has

b een extracted with petroleum spirit , nearly twice that breaking strain wil l b e requi red . A s for the elongation of guttapercha— i . e .

,the extent to which it will stretch before break

ing— it i s al so affected by the percentage of res in,being in

the last two cases,for in stance

,490 and 500 per cent . , respec

tively , but i t al so depends on the nature of the gutta .The earli est practical use of gutta-percha was for surgi

cal appliances— for bandages,spl ints , and receptacles for vac

c ine‘

virus . I t i s used for ear trumpets ; for the handles ofsurgical instruments

,as i t aff ords a firm grip and i s prefer

ab le to wood for anti septi c reasons ; in medicine , in the form(1) of a very th in t is sue , (2 ) of sticks , and (3 ) of a 10 percent . solution in chloroform ; for chem ical purposes , in theform of tubes

,pumps

,syringes , bottles , ,

and the l ike , and forladles and tub es for handling caustic alkal ies and corrosiveacids and liquids in chem ical works ; and for mechanical purposes , as rings and cups for pumps and hydraul ic pres ses andfor driving bands (belting ) . F or the latter purpose balata isal so us ed largely , interposed between canvas ; such belts can bej oined by means of a solution of balata or gutta-percha in carbon di sulphide . A nother application of gutta-percha i s that fortaking impres sions of medal s

,and al so of the interior of

large guns . Gutta-percha i s al so modeled into ornaments inthe shape of the leaves and petals of flowers , thi s being doneby working the gum by hand in hot water with one or two

USES IN INSULA TI ON 385

s imple iron tools . Such ornaments are often appl ied to thedecoration of j ars made of semi-porous ware

,the whole being

painted afterward .B ut the most important application of gutta-percha i s in

the insulation of submarine and subterranean cab les . Dr .

W erner von S i emens first proposed gutta-percha for insulati ng purposes in 1846 , and in the next year he designed ascrew press , for the s eam l es s covering of wires with thatmaterial

,which is sti l l in exi stence , while the principle of

the pres s i s st i ll adhered to . Gutta-percha has been foundto be very permeable to the X - rays , and it has been proposedto uti l ize th i s property to examine gutta-percha- covered wiresfor the detection of defects in the copper conductor, particular ly in “j oints

,

” or for finding air-bubbles . The X - rays mayalso be used for the detection of large foreign bodies in theraw gutta-percha .

The electric properties of gutta-percha depend ch iefly onthe nature of the gutta and to a less extent upon the res in ;but only very s l ightly on the relative proportion of thes e twocomponents . They depend al so upon the nature and amountof the impuriti es and on the water . The insulation and inductive capacity are li ttl e aff ected by the extraction of the res in .The in sulation should b e as high as pos s ib le , and the inductive capaci ty , for most purposes , as low as poss ib le , butwhereas the latter i s mostly as sociated with other good qua l it ies of the material , such i s not always the cas e with a highinsulation . A third electric property is called dielectricstrength

,or resi stance to piercing by high voltage . A thick

ness of a li ttl e over inch of gutta-percha breaks down withvolts , and one of about 1- 10 inch with volts:

Gutta-percha hardened b y the extraction of i t s res in i sused chiefly in the manufacture of go l f bal ls . Gutta-perchafor th i s purpose should b e tough , elastic , and not britt le atlow temperatures ; i t should b e specifical ly l ighter than water ,in order not to sink i f dropped accidental ly into a ditch . I t i srequi si te that the proper grade of raw material b e chosen andthat the resin be extracted as completely as pos s ib l e . To tes tthe elast icity of golf bal ls , a machine. is used , cons isting of (1)a perpendicular s cale

,divided into feet and tenths ; (2 ) a

386 GUTTA -P ERCHAc l ip

,at the top , for holding the ba l l to b e tested ; and (3 ) aniron p late at the bottom . The ob j ect i s to measure the re

b ound of the ball , when released from the cl ip and fall ingupon the plate . A ball made of gutta—percha , of which 25

per cent . was resin , rebounded only to the point on the scalemarked 30 ; a bal l containing only 10 per cent . resin reboundedto 45 ; and stil l another , having only a small percentage , re

bounded to 60—the highest point reached . A ba l l of balata,

having the resin thoroughly removed , rebounded to 59 .

Some figures wil l give an idea how greatly the physicaland mechanical properti es of gutta-percha are affected by theextraction of the resin . Careful ly selected specimens of am edium quality were cut fine and int imately m ixed

,and then

divided into two portions . O ne portion was next washed inthe ordinary way with water ; the other treated with petrol eum spiri t unti l nearly a l l the res in had b een extracted . The

two specimens showed the fol lowing analys esGutta . Res in. Dirt. Water . Total .

Cleaned in ord inary way 100

Same mater ial , hardened 100

The di ff erent phys ical and mechanical properties of thetwo specimens are indicated in the next compari son

O rd inary . Hardened .

Temperature when commenc ing to soften . . C. C.

Temperature when commenc ing to harden . C. C.

Time o f hardening 17 min. 45 sec.

Tens i le streng th— pounds per squareE long ation— per cent. 360 285

The e lectrical properties , on the other hand , are but l i tt leaff ected

,the i nsulation being practically the same as before ,

and the decrease of specific inductive capacity i s probably dueto the smal ler percentage of water in the hardened materia l .

The principal cause of the destruction of gutta—percha i sthe ab sorption of atmospheric oxy gen , which alters the guttaand produces a brittle resin of qui te a diff erent nature to thatorigina l ly present in the material . Thi s destructive ox id izat ion i s greatly ass is ted by l ight , and b y other causes— forinstance

,by any action tending to make the material porous ,such as alternate wetnes s and dryness

,the presence of sub

stances which exerci se a solvent action on gu tta-percha as awhole or any of it s components . Certain alkaline substances

388 GUTTA -P ERCHAGaullie combined gutta-percha with Roman cement by

means of animal gall , forming a plast ic material , capable ofb eing stamped and molded .Cooley mixed gutta-percha with res in oil under heat , then

mixed in carbonate of soda with roasted s tarch . To thi s compound he added asphalt to make it harder , or hyposulphiteof lead

,to make it softer . He also made a great many gutta

percha compounds in which salts were present . These hesteeped in water after mixing unti l they became soft andflexib le .Charles M acintosh made a compound for telegraph W i re

f rom gutta-percha , naphthalene , and lampblack .Charles Hancock boi led gutta-percha in muriate of l ime ,

passed i t between heated cylinders , s ifting the surface withrosin

,in the production of a compound for complete insula

tion . A nother of hi s compounds was made of gutta-percha ,shel lac

,and borax . H e al so made gutta-percha sponge by

mixing with it carbonate of ammonia or alum and applyingheat . He also made a hard gutta-percha wh ich was s imilarto vulcanite by mixing it with sulphur, putting i t in moldsand keeping the compound at a high temperature for severaldays .

Duncan invented a great many compounds for guttapercha cement , many of which are now in general us e . O ne

suggestion of his was the mixing of gutta-percha with Canadabalsam and shel lac , the resultant compound being a goodcement capab le of standing considerabl e heat and in no dangerof becom ing greasy on it s surface .

Robert Hutchinson claimed that he was able to rendergutta-percha les s l iab l e to oxidize , to improve its e lasticity ,increase its tenacity

,and dim i n i sh its l iab il ity to become s ticky

or tacky , by compounding i t with lanichol or wood cholesterin .(See Lanoline . )

F orster deodorized gutta-percha by mixing with it essentialoil , orris root , or gum benzoin .

Liquid gutta-percha is gutta-percha dissolved in chloroform

,to which a little carbonate of lead i s added in the shape

of '

a fine powder. A fter agitation , the mixture i s s et aside

VULCAN IZA TI ON 389

unti l the insoluble matter has settled . The clear l iquid i sthen decanted .

Spil l , in order to prevent gutta-percha that had been vulcanized from being attacked by grease , treated i t to a solutionof melted beeswax

,hardening this coating with an infus ion

of nutgalls .Gode froy mixed gutta-percha with powdered coconut shell ,

claiming that it would stand a higher degree of heat , and wasconsiderably more elastic .

,

Day , in America , mixed pipe claywith gutta-percha to prevent its sponging during vulcanization .The vulcanization of gutta-percha , i n spite of a common

impres s ion to the contrary , i s something that can be eas i lyaccomplished , and is analogous to the vulcanization .of indiarubb er . I t can be done by mixing with free sulphur or sulphid es that contain free sulphur, or by the us e of chloride ofsulphur. A s the P arkes mixture attacks gutta-percha veryeasi ly

,the dipping for vulcanization must b e very quick , the

artic le afterward b eing a l lowed to remain in the ai r for somehours . The s econd dip can be a li ttl e longer , as the surfacei s l ess eas i ly attacked than before . The vulcanized producti s qui te hard and wil l s tand a high degree of heat . Chlorideof sulphur mixed with b i sulphide of carbon can also be incorporated in a solution of gutta-percha and bi sulphide of carbon , with the result that the gutta-percha will b e thoroughlyvulcanized .

The late Robert Di ck,of Glasgow

,who was a succes sful

manufacturer of gutta-percha artic les in the mechanical l ine ,produced many vulcanizabl e compounds of gutta-percha ofgreat value , some of wh ich follow . He claimed that his compounded gutta-percha retained the good qualitie s of the gum ;

that i s,that it was homogeneous and plasti c at a moderate

heat , but tough and hard at ordinary temperatures , and thatit was just as va luab l e afterward for mixing and molding overagain .Compound No . 1 i s described as the hardest and tough

est , and may be us ed , in place of l eather and vulcanized indiarubber , for tires , bel ts , pul l ey coverings , hors e shoes , etc . No.

2 i s softer and more elastic,and suitab le for soles and heels

of shoes , wringer rol l s , springs , playing ball s , mats y etc . These

390 GUTTA -P ERCHAgoods are mixed in the usual way , and vulcanize in the masticator

,but not enough to take away the plas tic qualities of the

gutta-percha . F or treati ng this compound,a special masti

cator was devised by M r . Di ck, the rol l ing cyl inders beingho l low ,

and a B unsen gas-burner inserted through one endof the hol low axle , whil e the gases pas s off at the other, thusheat ing both rol ler and mixture . The outer cylindrical masticator i s j acketed and heated with steam :

COM P OUND N O . 1 .

P ure cleaned hard gutta-

percha

P ure c leaned tough se lected gutta-percha or balata (prefer

ably more rather than less )P ure cleaned “

low Wh ite gutta-

percha (preferably lessrather than more )

“Crumb

”or g round g ood old vulcanized ind ia rubber

Hardwood veneer dustSulphurZ inc oxide (or z inc dust)Flocking , or the cut fiber of cotton textile fabricsTotal

COM P OUND N O . I I .

P ure c leaned tough gutta-

percha .

P ure c leaned balata or s e lected gutta-

percha

P ure c leaned “low wh ite” gutta-

percha“Crumb

”or g round g ood old vulcanized ind ia rubber

Hard g round veneer dustFrench chalk, powderedSulphurZ inc oxide (or z inc dust)Flocking ,

or the cut fiber of cotton texti le fabr icsA lum, g round

Total 100

A nother compound patented by M r . Dick embraced theuse of low grade A fri can and B orneo rubbers , which , aftercleansing, were mixed with gutta-percha , while still moist, inhot water. A fter the mixing the compound i s treated under amoist heat , where the temperature i s 212 degrees to 240 degrees F . , the resul t b eing a tough , plas tic fibrous dough . Thi scompound is then , so the inventor claims , equal to any service for which the gutta-percha and balata compounds areus ed . A n important property in this compound .i s the shrinking quality which gutta-percha possesses , while its power ofcohes ion rendered i t especially valuable for i nsulating wires .

Shepard mixed gutta-percha with sulphur , exposed i t toa heat varying from 300 degrees to 350 degrees F .

,admitting

392 GUTTA -P ERCHAmers ing the gutta-percha in nitric acid , and then placing i t foran hour in a so lution of carbonate of soda , thus producing atougher wearing surface .

B arlow and F orster mixed g utta-percha with kauri gumand m i lk of sulphur for a cab le coating.M acintosh immersed gutta-percha in concentrated sul

phur ic acid for a number of seconds to harden the surface .He also mixed gutta-percha with gun cotton , curing withsulphuric acid , claiming that the resultant compound wasnot l ikely to be aff ected by the heat of tropical cl imates .

TYP ICAL GUTTA - P ERCHA CEMENT COM P OUNDS .

l .— F or j oining wood : gutta-percha , 11 pounds ; shel lac , 3

pounds ; Venice turpentine , 5 pounds ; pitch , 1 pound .2 .— F or uniting metal s , glass , stone , and earthenware

gutta-percha , 45 pounds ; shellac , 20 pounds ; gum mastic , 5pounds , oxide of l ead 12 pound ; s torax , 3 pounds ; Venice

turpentine,26% pounds .

3 .—F or cementing leather : gutta-percha

,4 ounces ; bisul

ph ide of carbon , 20 ounces ; asphaltum ,1 ounce ; common

res in,1 ounce .

4 .— Gutta-percha glue : gutta-percha , 1 pound ; rosin , 1

pound ; l itharge , 1 ounce ; powdered glass , quantum suflicit.5.— Shoemaker’s wax : melt gutta-percha

,20 ounces ; add

pitch , 58 ounces ; soap , 5 ounces ; rosin , 6 ounces ; beeswax , 5ounces ; palm oil , 1 ounce ; tal low , 5 ounces .

6 .— F or preserving metal s and other surfaces : coal tar

,20

pounds ; gutta-percha , 5 pounds ; minium , 6 pounds ; whitelead , 7 pounds ; pitch ,

10 pounds ; resin , 10 pounds ; spirit turpentine

,4 pounds ; sulphur , 38 pounds .

7— General cement : M ake a solution of balata of 5 ouncesin y, gallon naphtha , and another of gutta-percha 5 ounces ingal lon naphtha . Combine the two solutions and add 13ounces res in or pitch and sti r and mix thoroughly .

“Gentsch

’s gutta-percha” i s a widely used sub stitute for

gutta-percha,made in general as follows : the ingredi ents us ed

are mineral wax,tar

,resin , and rubber. The process i s thus

described by a sci enti st who visited the E ngl i sh factory . A

m ixture of res in,wax

,and tar was thrown into a kneading

machine , steam being applied from below to keep the tem

ANALYS I S O F GUTTA -P ERCHA 393

perature at the proper point . Twenty minute s later , the masshaving been kneaded meanwhile , the steam was turned off

and the rubber (cut into smal l p ieces ) added , being fed inslowly to prevent j amming of the knives of the kneadingmachine . The machine was stopped from time to time to testthe condition of the mass , and at the end of three hours thesolut ion of the rubber was found to be complete and the masswas removed from the machine and passed between roll ers ,coming out in s lab s inch thick— the finished material .

THE A NALYS I S O F GUTTA -P ERCHA.

TH I S of course refers to the analys is for the crude gum ,

and,to have the analysis complete , i t should cover the amount

of water present , the amount of foreign matters and impurities

,the amount of ash , the amount of pure gutta , and the

amount of resins .The water i s eas i ly determ ined by heating a known weight

from the sample at a temperature ranging from 212 degreesto 230 degrees F the los s in weight being the amount ofwater present . This i s a common proces s in chemical analy5 15 . I n the case of gutta-percha , i t must be varied , as thesample is l iab le to oxidize even under examination

,causing

an increase of weight . Thi s i s overcome by conducting theheating in a slow current of nitrogen

,or carbonic acid gas .

J . A . M ontpel l i er ; devi sed an apparatus for thi s , whichcons isted of a special retort with a large opening which heus ed as a vapor bath and having a tubulure at it s side . I t i sclosed by a large cork

,in wh i ch there are two holes

,one for

the tub e which is to introduce the gas , and the other for thethermometer . The sample to be dried i s placed in a crucib leof porcelain or platinum suspended within the retort . A s thewater evaporates i t i s borne by the current of gas througha tub e inserted in the s ide tubulure , and into U- shaped tubes ,containing sulphuric pumice

,which retain it . F urther on

the U- tubes are connected with a Liebig tube with five bulbscontaining pure sulphuric acid to prevent the entrance ofmois t air after the apparatus cool s , a further use being tomake i t poss ib l e to regulate the speed of the current of gas .

The retort i s immersed in an oi l bath heated by a B unsenburner. I f carbonic acid be used it i s obtained by the action of

394 GUTTA -P ERCHAhydroch loric acid on marb le chips produced in a Kipp apparatus fol lowed by wash flasks , the first of which contains potass ium b icarbonate in solut ion , which i s intended to stop thepas sage of any hydrochloric acid , and the second containingsulphuri c acid at 150 degrees to thoroughly dry the gas . To

be ab solutely sure that th i s gas i s dry a des s icator fil led withsulphuric pumice i s placed b etween the retort and the secondwash flask . The O peration of drying one gram with thisapparatus takes 6 to 7 hours . The determ ination of theamount of impurit i es , which comes next , may be eff ectedvery easi ly , by using M . J . Jean’s exhaust apparatus . A smal lpart of the sample

,from one-half a gram to a gram , i s weighed ,

cut i nto smal l fragments, put in a fil ter

,the weight of which

i s known , which in turn i s placed in a platinum cone . Thi scone i s then put in the extens ion of the apparatus ; thi s extens ion communicates by two tubes with the retort containingpure chloroform . A condenser

,i n which a current of cold

water constantly ci rculates in order to condense the chloroform vapor, i s placed at the upper part of the extension .

The retort rests on a sand-bath,very gently heated by a

B unsen burner . Under the influence of the s light heat thechloroform evaporates , passes through one of the tubes , anddrops on the fi lter containing the gutta-percha , which it gradually di s solves . The solution , pass ing through the fil ter, thendrip s into the retort through the second tube .

A l l the impuri ties remaining in the fi lter, i t i s sufli c ientto dry and weigh the fil ter to get the weight of the fore i gnmatters . The drying should be done in the apparatus used indetermining the amount of water.

The next process i s the determinat ion of the amount ofash . I n gutta-percha thi s i s always very smal l , as mineralmatter i s almost entirely absent from it , the quanti ty neverexceeding one-half of 1 per cent . The amount of ash i s determined b y burning in a capsule of platinum a known weight ofgutta .

The fourth step i s the determination of the amount ofpure gutta

,and of the resins . B oth fluavile and albane are

solubl e in absolute alcohol at the boi ling point , and as puregutta i s insoluble in it , thi s i s a very ready means of separa

396 GUTTA -P ERCHAgums have diff erent constants and characteristics— in somewidely diff erent, and in the cases of the gums above cited suffic iently diff ering to make identification of their parent gum aneasy matter. F rom the gums so far examined it i s hoped toestab li sh the fact that the combined evidence o f the constantsand characteristics of the resins, together with the character ofthe accompanying hydrocarbons , will show that each species ofgum varies f rom each other sufficiently to make diff erentiationof unnamed specimens complete , and to establish the fact thatevery specimen of the same species of gum i s alike in the characteristics quoted .

RESUME O F ANALYTI CAL WORK .Gutta-perchal—Res ins , soft, pasty , yel low.

Chicle.—Res ins hard , g rayish yel low, br ittle.

Tuna— Res ins hard , dark yel low, br ittle.

A lmei d ina— Res ins hard,br ittle

,yel low.

Jelutong .— Res ins soft, brittle, yel low.

B alata.— Res ins turb id l iquid , y el low.

P ay ena.—Resins simi lar to chicle resins.

Saponification Acidvalue . value .

*Gutta-

percha res ins 5*Gutta-

percha (albane )*Gutta-

percha (fluavile )*Ch icle r es ins TraceCh icle (res in A ) Trace

Ch icle (r es in B ) Trace

TTuno res insTJelutong TraceA lmeid inaBalata Trace

TP ay ena spec ies Trace*Average of 4 spec imens .

'

l'

Averag e of 2 specimens .

While the saponification values of gutta-percha , tuno , andj elutong resins respectively are almost identical,their separation

into component resins corresponding to albane and fluavile ofgutta-percha gives entirely diff erent results f rom the latter andfrom each other . The resins of chicle and P ay ena diff er aswidely and the accompanying hydrocarbons are quite different .

A nalyses of common gutta-percha, by Edouard Heckel andF r . Schlagdenhauffen

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O OOO O O O O O O O O O O O O O O O

A NA LYS IS O F RES INS 397

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Total 100 100

Gutta-percha is made of a mixture of hydrocarbons , andthere is usually present a certain amount of oxygen . A ccordingto Granville H . Sharpe , its ultimate composition is

Carbon

Hy dy rog en

"Spec ific g ravity, to

The primary analysis o f gutta-percha by Sharpe isHydrocarbon

Total 100.

Obach gives the following average results f rom a large number of analyses of each of twelve leading brands or sorts ofgutta-percha

Gutta . Res in . Water

P ahangBandier r ed

Bulongan red

Bag anGool ie r ed soondie

SerapongBulongan wh iteM ixed wh iteBandi er wh iteSarawak m ixedP adang rebo iledBanca r ebo i ledA nother series of analyses by O bach relate

ents of the resins in gutta-percha , as followsO O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

398 GUTTA -P ERCHABALATA .

B ALATA is the gum of the “bully or bullet tree— theM imusops balata— found in B ritish and Dutch Guiana , and inVenezuela . I t is marketed in two forms

,

“block” and sheet.”The sheet is usually worth about 30 per cent . more than the blockbalata . The sheet is used for belt covering, while the block ismore used in compounding. B alata i s usually reddish gray,though sometimes brown . The dried sheet milk or sheet productusually contains 39 per cent. gutta and 37 per cent . rosin ; whilethe boiled or block contains 51 per cent . gutta and 48 per cent .rosin . The sheet shrinks from 10 to 20 per cent . while the blockshrinks from 20 to 30 per cent .

The balata tree may be tapped when 5 inches in diameter.I f tapped too deep, the tannin sap injures the product, and thewound is slow to heal . The outer bark is removed before tapping.The milk runs for about three hours , and a tree will generallyyield about liters of mi lk, or l to 2 kilos of balata . I t

usually requires about two weeks for the milk to dry.In character this gum occupies a position between indiarubber and gutta-percha , combining in a degree the elasticity of

one with the ductility of the other, and freely softening andbecoming plastic and easily molded in hot water. Balata is driedordinarily by evaporation . A more rapid coagulation is eff ectedby the use of spirits o f wine . A lum i s sometimes used to coagulate , but is not very satis factory. The gum i s sometimes mixedduring the gathering with the mi lk that produces gum known astouchpong and barta-balli . I t i s used principally in the manufacture of belting and for insulation work . I t has been util izedalso for gol f balls and as a substitute for rubber in dress shields .

400 INDEXA damanta 119

resm 154A dam

’s process for uniting rub

ber to metals 260

A ddah N ig g ers rubber 20

A dhesor 119

A fr ican rubbers 17rubber sources 9

,17

A g almatol ite 89

A ir brake and s ignal hose tests . 343

A lcohol 48, 230

Denatured 231

A lexander rec la im ing 295A lex ite 141A lg in gum 119A l lard fire proof fe lt 255A lme id ina rubber 33A ls tom

'

a plumosa 41A lum 48

,194

A lum ina 89A lum in ite 89A luminum flake 89

lanolate 213oxide 89

sulphate 195A lundum 89

A ly ing’

s rubber cure 58Amazonian res in rubber 34Amber 154Burm ite 158

res in substitute 119

Ambr iz rubber 23Ambroin 141

Amer ican proces s z inc 190Amer ican showerproofing com

pound s 252Amer ican Soc iety F or Testing

Mater ials ; methods of 321

Amianthus 91

Ammonia 196Ammonium carbonate 196

ch lor ide 197mur iate 197

tung state 197Amole juice 48

Amorphous sulphur 63

Amph ibol ine 89, 255A nalyses of oil subst itutes

(tab le) 118

A nder son rec la im ing 295A ngola rubbers 23

A ngostura rubber 13

A nhyd r ite 90

A ni l ine 197

co lor s for rubber

g?40


0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

O O O O O O O O O O O O O O O O O O O O

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0



O O O O O O O O O O

O O O O O O O O O O O O O O O O O O O O O O O


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0



A nthracene 232, 239A nt imony 90

cr imson sulph ide 184

golden sulph ide 191

iod ide 198

oxide 90

pentasulph ide 68

red 66A ntipolo gum 34

A pocynacew 7A rab ic , Gum 155A rg i l laceous red shale 90

A rkos ite 155

A rmalac 141

A r s enate , P otas smm 204

A r senic 90yel low 191

A r temis ia abs inthiwm 227A r tocarpacew 7A rtocarpus inci sa 34

interg r z’

folia 35A ruwim i rubber 22

A sbestic 91

A sbestine 91

A sbestonit 120

A sbestos 91A nalys i s of 92

A sclepiadaceae 7A spha lt 155

A rtific ial 156French 162

Lithro- carbon 165Manj ak 166

M inera l i nd ia rubber 166

Retin 170Tr inidad 174

A s sam rubber 25

wh ite 38

A s s inee rubber 20

A s trag alus gummifera 174

A str ictum 120

A tallea ex celsa 45A tm ido 92

A tmo id 92

A ttoaboa rubber 20

A ureol in 192

A ylsworth’s Condens ite 144

A xim rubber 21

A . R. D. Gum 119

I NDEX 401

Balsam 156

Canada 158

of storax 156

of sulphur 156

Tolu 174

Balsams in rubber compound ing 153Banana rubber 34

Bangui rubber 22, 378

B annig an rubber cure 57B arabarj a rubber 24

B ar beris vulg aris 192Barber ry ye l low 192

Bar ium carbonate 92, 95

ch lor ide 198

sulph ide 64

wh ite 186

Bar low and Forster’s gutta-

per

cha compound 392

Barta-Bal l i gum 34

Barytes 92

B ashnag el’s rec laiming proces s . 293

Bas le’s rec laim ing process 296

Bas s am rubber 19

B ass ia P arkii 37

B asofor 93

Batanga bal l rubber 21

Bathurst rubber 19

Bayin rubber‘

20

B ead le and Stevens , analyses of

H evea latex 44

b leach ing of crude rubber 53

mechanical impur it ies inc rude rubber 309

Becton wh ite 187

B eeswax 156

B e ira rubber 35

Be lg ian Congo rubber 22

B elled in’s proces s for leather

impregnation 120

Bengue la rubber 23

B en in bal l rubber 21

Benton, preservation of rubber

goods 258Benzene 232, 240Benz ine 239, 240Benzoin 157Benzol 232

Benzole 232

Bernste in, vulcanization by ultraviolet rays 62

Ber ry , analys i s of gutta-

percha

res ins 395Besk 26

Beta separator 50

B etite 142

B ever ly Rubber Works 293

B ey l ikg y’s rec la im ing proces s . . 295

B iborate , Sod ium 207

B ichromate, P otass ium 204 a

B irch-bark tar 157Bi scuits , A fr ican 19B i sulphate, P otas s ium 204

B isulph ide, Carbon 234

subst itute , Carbon 235B i sulph ite, Sod ium 208B itumen 157A uvergne 157Black, A nt imony 93

Bone 179Carbon 179Gas 179Graph ite 179Hyd rocarbon 179Hypo 64 178

Jet 179Lamp 179lead 93

P ar is 180

p igments for rubber 178

p itch 158Satin g los s 180

Blanc fixe 93

Bland ite 120

B landy’s patent subst itute 120

Bleach ing powder 198

B lown o i l s 213

Blue, Ch inese 181

Chrome 181

Cobalt 181

I nd ig o 181

lead 93

Molybdenum 181

p igments for rubber 180

P russ ian 181

Saxon 181

Smalts 182

Thenard’

s 181

Ultramar ine 182Ya le 183

Bol ivi an rubber 12

94

b lack 94

naphtha 237

Book gutta 26

Boot s and shoes . Compound s for 360

Dry heat cure of 358

M anufacture of 357

P res sure cure of 359

Varn ish for 361

Borac ic ac id 199

Borate ,Z inc 187

Borax 199 207

B orcherdt’s compound 120

Borneo rubber 25

No. 3 38

B orracha 14

B os sang a rubber 48

Botany B ay gum 153

402 INDEX

Boug iva l wh ite 187

Bourn’

s rec la im ing process . 294

B ras s ica campes tris 225B r ier ly

’

s patent art ific ia l elaterite 120

B r immer’

s rec la iming 296

B r iti sh gum 158

B r ittlenes s in rubber goods 257

B r ixey’s Ker ite formula 128

B rom ine 64

B rooks ite 143

B ros ium galactodendron 37

B rown p igments for rubber 184

B rown’s hard rubber subst itute . 143

B ucaramanguina 94

Buki rubber 23“Bul let” tree gum 398

Bul ly” tree gum 398

Bumba rubber 23

Burgundy pitch 158

Burm ite amber 158

Burnt hypo 64

umber 94

B us s ira rubber 22

Butanes , Rubber s from 272

Button lac 158

Buttons , A fr ican 19

B uty rospcrmmn P arku 38

CADM IUM yel lowCadoret

’

s r es inol ines

Calam ineCalc ium carbonate

ch lor ideoxalateoxidephosphatesulphatewh ite

Calculation of analysesCalender ing rubber

Ca lome lCalony ctz

'

on spec iosumCalotropis g ig antea

Cameroons rubber

Cameta rubber

Campbel l and Cushman’

s punc

ture fluidCampbe l l’s Endur ite

CampheneCamphor

O i l of

Canada ba lsamCandel itta

'

wax

Cand le tar

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

O O O O O O O O O O O O O O O O O O O O O

0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0


0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0



0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0

Ceras inCeratoma s tlzqua

Canoe gums 35Caoutchene 121Caoutchite 121Caoutchouc aluta 143

oil 214

Caoutchouc ine 234 376Cape Coast rubber 20Carbol ic ac id 199Carbon b i sulph ide 234

b isulph ide subst itute 235b lack 179tetrachlor i de 235 244

Carbonaceous c lay 95Carbonate , Bar ium 95

P otass ium 204

Sod ium 208Carbo-nite 143Carburet of i ron 95

'

Carn gum 159Carnauba wax 159Car rol gum 121

Carr’

s patent cerea l gum 121Car se l y e l low 102Cartag ena rubber 15Case in 159Caspar i crude rubber valuati on

methods 308

tetrabrom ide method fordetermining rubber 310

Cas tilloa elas tica 9tunu 43Ulei 9

Casti l loa plantation rubber 31Castor o i l 214

Catechu 200Cativo gum 35Cattimandu gum 35Cauchin rubber 39

Caucho rubber 13 14

Caulbry’s rubber cure 60

Caustic potash 205soda 209

Caviana rubber 11

Ceara rubber 16

plantation rubber 31

Cel lazote 267Cellit 143Cel lul ith 143

Ce l lulo id 143

Ce l lulose 143

Cement, Gutta-

percha 392

P ortland 109

Rubber.372

Centra l Amer ican rubber 14 3 1

plantat ion rubber 31

160

404 INDEXComp

’

ound ing ,Reasons for rubber 89

Waxes in rubber 153

Conakry rubber 19

Con- cur rent rubber 122

Condens ite 144

Congo Free State rubbers 22

plantat ion rubber 31

Consol idated oil 215

Cooley’s art ific ial 156

gutta-percha compound . 388

Coorong ite 36, 160

Copal 160

Copper sulphate 200

Coral ite 145

Cor imite 145

Cork 97122

Corkal ine 122

Corn oil 215

subst itute 122

Cornite 145

Cornwal l c lay 98

Corundum 98“Corus cus

” finish 99

Corypha rerifera 1

33Cottonseed oil 215

'

Couma uti lis 37

Cout inho mach ine 50

Cow tree rubber 37

Coyuntla juice 48

Cravenette process 251

Cream of tartar 201, 204

Creosote oil 215

Cr oton draco 171

Crude rubber , Bleach ing of 53

Caus e of color in 52

Mechanical and chem icalre lat ionsh ips of 345

P hys ica l tests and analys es of 302

Shr inkag e of 263

A fr ican g rades of .263 , 264

Calculat ion of 265

E ast Ind ian g rades of . 264

P ara g rades of 263

Valuat ion of .303

Class ificat ion in 306

Cor re lat ion of tests in 305E stimat ion of mo i sture

310

E stimation of rubber in 310Fol’s conc lus ions ou . . 305Form for 310

Gorter’s viscos ity in

dex in 306

M echan ical impur it iesin 309

Mo isture in 310

0 0 0 0 0 0 0 0 0



0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0

0 0 0 0 0 0 0

0 0 0 0 0 0 0


O O O O O O O O O O O

0 0 0 0 0 0 0 0 0 0 0 0 0

Crude rubber—ContinuedValuation of- Continued

N itrog enous insolub lematter in 309

P ract ica l considerati ons on 309Schm itz method for 309

O utl ine s cheme for 304P hys ical and mechani

cal 311A dhes ive tests in 311Mechanical tests in 311V iscos ity tests in 311Vulcanizat ion testsin 311

S econdary p r o d ucts(rubber

'

res ins) in 308S chid rowitz method of 307Sc ient ific method for . 304Tetra-brom ide method

for rubber in 310Wash ing loss in 311

Cuma i rubber 37Cumaka-bal l i 35Cutch 200 201Cyanide , P otas smm 205Cy co 266

DA FT’

S process for uniting rubber to metal 260

Dammar 161Dankwerth

’s Russ ian subst itute 122

Dannin’

s mach ine 50Day’s Ker ite 127

us e of p ipe c lay 108De Costa’s apparatus 51Denatured alcohol 231De P ont’s subst itute 145Dental and stamp gum, Com

pounds for 373Manufacture of 373

Deodor ization process 256Bourne’s 256Cattel l’s 256De la Granj a’s 256F reeley

’

s 256Hancock’s , Char les 256Lavater and Tranter’s 256Traun Rubber Co.

’s 257

Dermat ine 122

Derry,’s waterproof harness o il . 226

Dextr ine 161

Dextros e 161

Diatite 145

Diatomaceous earth 98

Dichlor - ethylene 236

Dichops is elliptica 41

poly antha 379

INDEXDick’s gutta-

percha compounds389, 390

Dieffenbach’s rubber cure 56

Dimethyl butanes , Rubbers from 272

Dippe l’s oil 237

Divi s ions of rubber manufacture 354Doebr ich

’s compound 123

Donald son’s e lectrolyt ic method

for lead and z inc . 332

Doremus fire proofing process . 255

Dow’

s inner -tube fi l ler 266

Drugg ists’

, stationer s’ and surg i

cal sundr ies Com

pound s for 361

Manufacture of 363

Dry heat 54

m ixing 359

Rubber 352F i l lers in 89

Unusual 115

Dry ing oil 227

Dul l fini shDuma

’

s canvas sai l wate rproofing 255

Duncan’s gutta percha compound 388

Durant patent for b leach ing gutta percha 236

Durate 123

Durvez’

s rec la im ing proces s 296

Dutch Congo bal l rubber 22

l iquid 237

pink 192

Duvivier and C haudet’s gutta

percha compound . 391

Duvivier’

s gutta-

percha c o m

pound . 108

Dye ing rubber 247Frankenburg’s a n i l inelakes for 249

Hoffer’s method for 247

P arkes’ formulae for . 247

Dy em cos tulata 26

EARTH wax 161

East A fr ica rubbers 23

East Ind ia rubber 25

Sources of 9

Eaton, B . J. and Grantham J., on

opt imum cure .71, 73

Eaton’ ,s A . K., rubber cure 56

Ebner’

s patent A . R. D. 119

Ebonitine 145

E ckste in’s Hya l ine 147

Ekert’s h igh pres sure compos it ion 123

E laste ine 123

Elastes 266

E lastic g lue 123 ,161

E lastic ite 123

0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0

405

E lastite 123E laterite 130 161

A rt i fic ial 119E lateron hydrocarbon 131E lectr ic coagulat ion proces s 52

cur ing process 63

fin ish 98

propert ies of gutta-

p e r

cha 385E lectroplating on rubber , Goodyear’s method of . . 248E lectrose 145E lemi 162E lmer

’s rubber cure. 59

E lworthy’s proces s for preserving

rubber goods 258Emarex minera l rubber 131Embos s ing rubber 248

B ourbr idg e method for 248Emery 98Endur ite 124

Eng l i sh 5 h o w e r proofing com

pound 253Entrafina P ara rubber 10Enzymes in crude rubber 52Equateur rubber 22E sbenite 145E smeralda rubber 15Ether 237Ethyl ch lor ide 237Eucal iptia 215Eucalypius g lobulus 215Eucalyptus oil 215Eucommia ulmoi des 42

Euphorbia drag eana 4?lactiflua 34

rhipsaloides 34rubber 34, 124

34

trig ona 35Euphorbiacea 7Euphorb ium, Gum 162

Eureka vulcaniz ing compound 64

Ever lastic 266

Eves’s rec laim ing process . 296

FAGIOLI puncture fluid 266Fa lke and R ichard’s rubber cure 56Faraday’s analys is of latex 266Fard’s Spanish wh ite 187Far ina 98Faure’s rec laiming process 294

F ay ol le’s substitute 124Feldspar 99Fenton’s artific ial rubber 124F iber , Vulcan ized 152F ibr ine-Chr ist ia gum 124

406 INDEX146

162

9

3934

Vog eln 9F ig juice proofing 124F i l lers in d ry m ixing 89F ine P ara rubber 10F ire c lay 99

A l lard’s 255Doremus

’255

Dumas’

255

proofing 255F irmus 124F i sh g lue 162

oil 216Flake , A fr ican 18F l int 99Liquor of 202F lorence z inc 190F lour , Glas s 99

P hosphate 100

F lour ide, S i l icon 206F luvia 26F ol on valuat ion of crude rubber 304Form ic ac id .48, 201Forster’s gutta-

percha compound 388showerproofi

'ng c o m

pound 254Fos s i l far ina 100flour 100

meal 100

F osterom’

a g raci lis 39F ouquiera splendens 40F rankenburg

’s ani l ine lakes

0

249

non inflammab le rubber

solut ions 230

puncture fluid 266Frankincense 162Frankl in subst itute 125Frank-Marckwald’

s coagulat ionprocess 51French asphalt 162

chalk 100

Congo rubber 21

gutta-percha 125

proces s z inc oxide 190

rec laiming process 296talc 112

West A fr ica rubbers 19

wool g rease 216

F rost rubber 125Ful lers’ earth 100Fulton wh ite 188Fumero of van den Kerckhove . 51

F untumia elas tica4g

Fuse l oil 231

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0




0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0

0 0 0 0 0

0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0

O O O O O O O O O O O O O O O O O O O O O O O O O



GABOON rubberGa lal ithGal ipotGamb ia n ig g er sGamb ie rubberGambog eGambr iaGar icz

'

nia morellaGarnet lacGarn ier’s rubber cure

Garr 1ty and Avery’s proces s for

unit ing rubber to

metal s 260Gas proofing 261

B ousfield’

s 261Churrel

’

s bal loon 261compound s for 261, 262P el len’s 261

Gascardia M adag as cariensis 40P err ier i 40

Gasol ine 237Gaul l ie

’

s gutta-percha compound 388

Ge lat ine, Glug los s 163Genasco hyd rocarbon 131Gerard

’s rubber cure 68

German b lack substitute 120

showerproofing c o m

pounds 252, 254Gerner

’s Hevenoid 126

Gi lbert-B esaw’s rec laiming proces s

E lasticF i shWaterproof

Glug loss g elatineGlutenGlycer ineGoa g um

Godefroy’s gutta-

percha c o m

pound'

389

Gold Coast rubber 20

Gold , O xide of . . 100

Golden ant imony sulph ide 66 , 191

Go ld ing’s Rubber ic , Formula for 135Gold ste in’s unvulcanized washers 138Golf bal ls , Gutta-

percha 385I f ard core 146

Goodyear’s , Char les , hot vulcanization 55

lead acetate patent 102tr iple compound 114, 248

N e lson, ind ia r u b berleather 126

408 INDEXH ancock’s— Continuedvapor cure 60H ancornia Speciosa 16Hard rubber compound s 371

Manufacture of 141, 371subst itutes 141

Harmer’

s subst itute 126Harr ies

’s formula for 271rubber researches 271

Harr is’s rubber cure 56Hatchetine 166Havermann

’

s rubber cure 58Hayward’s rec la iming 294Heat cure 54Hebblewaite and Holt’s proces s . 251H ecke l and Schlag denhauffen

’s

analyses of guttapercha 396

H einr ichsen and Marcusson on

rubber res ins 308H e inzer l ing

’s rec la im ing proces s ,

294, 297Helbronner and Bernste in’s ultraviolet rays cure .6 l , 62

H elenite 164H e lfer’s process for coagulat ion . 49Helm’

s rubber cure 58, 65Hematite 184

Henr iques’ analysis of vulcanized rubber 312

analyses of o i l sub sti

tutes (tab le) 118Henr i’s ultra violet rays 61

Heptane 237Hermiz ing proces s 57H evea B raz iliens is 9latex , A na lys is 44

P lantation 71Heve rubber 39H eveenite 126

Heveenoid 126

Heyl -Dia’s rec la im ing process 297H inr ichsen

’s review of synthet ic

rubber 270Honduras str ip rubber 15Honeycomb sulphur 67Hopkinson’s Vulcanine 139Hung ar ian g reen 183Hunter’s O sse in patent 106

gutta-

percha compound . 388Lanichol 218

Huth’s Insul ite 126

Hya l ine 146Hyatt and P enn

’s rec la im ing

proces s 297Hydrocarbon b lack 179

rubber 126Hydroch lor ic ac id 201

Hydrog en peroxide 201

H y d rolaineHy d roleneHyposulph ite , Lead

Sod ium


0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

O O O O O O O O O O O O O O O O O O O O

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0

0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

JA CKSON’S printer s’ rol lers com

pound

Japan waxJava rubber

IDRI AL I N 164Ike lemba rubber 23Ind ia rubber leather 126

Solub i l ity of 228Ind ian gutta-

percha 41hemp rubber 39red 185

Ind igo b lue 181I ndig ofera 181I nd r ial it 164Infusor ial earth 101Inr ig 266Insolac it 147Insulate 147I nsulated Wi re, Compounds for 369

Manufacture of 368Insulation, Bureau of Standards’

method s of analys is of

Compounds forMay all

’

s tapeMulholland

’

s

Jo int Rubber InsulationCommittee’s o u tl ine of analys i s of

(tab le)Spec ification for 30 per

cent. H eveaSubmarine cab le

InsullacInsul iteI od ide , Z incI od ineIpomarza bona-nox

I reson’s packing compound

I ron, Carburet ofoxide red

peroxidepyr ites

I sanga rubberI s ing lassI s lands fine P ara rubber

I solatine

I soprene

Rubbers fromI ta ituba rubber

INDEXJe lutong 25, 39

res in 164

Jequie rubber 16

Jet b lack 179Jeve rubber 39

Jintawan gutta 39Johnstone’S non-drying compound 127Jo int Rubber Insulat ion Comm ittee , Ca lculation ofanalys es of 321

Method s of analys i s of ,321, 322

outl ines of analys is . 322

Requirements of spec ifi

cat ions of 334

Spec ificat ions , by whomadopted 337

Jones’ substitute 127Jose lyn’s rubber cure 57Jungb luth’s compound 127Jun iper gum 165

Justs’ ac id -

proof 127

KA M P TULI CON 127Kaol in 101

Kapak 131

Karavod ine’

s rec la im ing process 297Kar ite gutta 38Kasenoid 147Kas sa i rubber 23

Katanga rubber 23Kau Dreg a gum 41

Kaur i gum 165Keene’s gutta-percha compound . 391

Kelgum 127Ke l log’s Kelgum 127Ke l ly’s process for bronze eff ect

on r u b ber -coatedfab

‘

r ics 249

Kempeff’s hard rubber subst itute 147

Keratite 147Keratol 147Ker ite 127Formula for 128Kermes 101Kerosene 217Kess ler’s rec laiming 297Kianizing proces s 254K iel’s compounds 148

Kiese lguhr 102

King’s ye l low 191

Kir rage compound 128K itte l’s rec la im ing process 297Kle in,

Link and Gottsch’s ani l inemethod for analys is of vulcan izedrubber

Koalatex

409

Koener’s rec laiming 297Kommo1d 128

Koneman’s rec la1m1ng 297

Kormte 148

Kremmtz wh ite 188

Kw1lu rubber 23

LA BELLE’S m ineral rubber 131Laboratory, Equipment of works 303

171158163171

153Lactitis 148

Lagos rubber 21

Lahou rubber 19

Lake Leopold rubber 22

Lallemantia iber ica 218

o il 218

Lam ina fiber 149

Lampb lack 179

Lamplough’s Volenite 138

Lamu ba l l rubber 24

Landolphia 7

Carpodinus 9

Clitandms 9Lang

’s Nove lty rubber 131

Lanichol 218

Lanolate , A lum inum 213

Lanol in 218

Lard oil 219

Lar ix E ur opea 245Lascel les -S cott on naphtha 240

methane rubber so lvents 239on minera l wool 106

Latex, Rubber 8

A dulteration of rubber 34

Amapa 34

Molango 34

Sucuba 34

Surva 34

Tamanguiro 34

A nalysis of H evea 44, 266

Lavender oi l 219

Lavendula mm 219

Lead acetate 102, 202Blue 93

carbonate 102

n itrate 202

oxide 102

oxych lor ide 102

peroxide 102

Red 110

Sub l imed 112

Sugar of 102 112 202

sulphate 102

410 INDEXLead— Continued .

sulph ide .68, 180

Wh ite 113

Leadbetter’

s M eta l ined rubber . . 130

Leather , Cooley’s art ific ia l 102Leather ine 128

Leathero id 149Leatherubber compound 128Lemon o il 219

Leonard’

s substitute 128Les snenn and We inkopf

’

s formula 251

Leva’s d ry ing process 46Liber ian rubber 20Liconite 128Lig ro in 240

Lime 49, 102juice 49

P hosphate of 95Lime ite 129

Lin i gum 165Linoxin 129

Linseed oi l 1 219

Manganated 221

Linum us itatiss imum 219Liquid rubber 131

Liquor of 202

Litharg e 103

Litharg r ite 104

Lithog raph ic varni sh 220

Lithopone (l ithophone) 104, 188Lithro- carbon 165Little known rubber s 32

Liver of sulphur 68

Liverpool pres sed 18

Loanda rubber 23

Loango rubber 21,23

Lombiro rubber 24

Lom i bal l rubber 21

Lopor i rubber 22

Loranthus rubber 39

Lucas’s gutta-

percha compound . 391

Luff , B . D. W., on synthet ic rub

ber

Luft’s cel luloid rubberLugo

rubberLump rubber , A fr icanLuvituku rubber

MCCA RTNEY’S reclaiming process 295Maboa gum 39

Machacon juice 49

M ach ines . Coagulat ing 50

Beta separator 50

Cout inho’s 50

Da-Costa’s 51

Danin’s 50

0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 00 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0

Machines— Continued .

Van den Kerckhove’

s

fumero

Wickham’

s

Mac intosh’s gutta-

percha com

pound 388

Mackintoshes , Manufacture of 364MacMahon

’

s Maponite 129Macwarr iebal l i gum 39Madag ascar rubber 24

B lack 24

P inky 24

Madanite 129Made ira rubber 12Magnes ia, Heavy calc ined 104

Light calc ined 104Ma ize oi l 215M ajung a rubber 24B rown cure 24

nig g ers 24

Unr ipe 24

Malaya rubber 29,

Male rubber 43Mana 38M anaos rubber 12Mandarnva rubber 39Manegatu gum 39Mang abe i ra rubber 16Mang a

- ice rubber 39Mang anated l inseed 0 11 221

Mang anese , Destruct ion of rub

ber by 105P eroxide 105

Mam’

hot dichotoma 16Glaaiovii 16

Mani la gum 166Manjak 166Manoh twi st rubber 20M anufacture of rubber goods 351Maponite 129

Marb le flour 105Marcy’s rubber cure 55 56, 57Marks’ rec la im ing process 294, 298

Mar loid 149

Massaranduba rubber 39

Mas s icot 105

Mastic 166

Mathew’

s proces s for colored des igns on proofed

fabr icsMatto Grosso rubber

May all’

s rec la im ing processtape insulat ionM ayumba rubberMechanical rubber goods A naly

s is of

Compound s forManufacture of

412 INDEXNove lty rubber subst ituteNut- g a l lNuts , A fr ican rubber

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0

O B A CH ,A nalyses of gutta-

percha

compos ition of guttapercha res ins

O cati llo rubber

O ceanica rubber

O cher , Red

Yel lowO hmlacO il , Blown

CamphorCaoutchoucCastor

Cod - l iverCo lzaConsol idatedCorn

Cottons eedCreosoteDer ry’s waterproof har

nes s

Dippe l’sEucalyptusF i shFuselKeroseneLal lemant1a

Lard

LavenderLemon

LinseedMaizeMang anated l inseedM i rbaneMustardN eats footof vitr iolO l iveO riganumO r r i sP a lmCongoLagos

Wh iteP eppermintP etroleumP ineP oppyseedRapeseed

RockRosemaryRos inRus s ian m ineral P arkeseine

O il —C0 ntimwdShale 225Tar 226Thyme 226Turpentme 226, 245Vulcan ized 226

Walnut 226Wh ite d rying 227Ra11goon_ 224

Wormwood 227O i ls used in rubber compound s . 213Okonite 132O ld Calabar rubber 20 21

O leargum 221

O le ic ac id 203O leo res ins 167O leum wh ite 188O l ibanum gum 167O l ive oi l 221

O l ivier’s ultra violet rays cure 61

O ls son’s Zackingumm i 140

O pt imum cure 71 346O rang e bal l rubber 23

mineral 106

verm i l ion 185

O r inoco rubber 13O r r i s o il 222

O r r’s wh ite 189

O s se in 106

O stromis lensky’s theory of vul

canization 275

O xal ic ac id 203

O xidat ion and vulcanization Veloc ity of 285

O x imony 185

O xol in 132

O xydases in crude rubber 52

O ysters , A fr ican 19

O zocer ine 167

O zocer ite 168

P AGODITE

P ala gumP alm oil

CongoLagos

Wh iteP alo Amar i l lo gum

coloradoP anama rubber

P antasote

P aipaver s omniferumP ara rubber

P araffi n waxP aragol

P ar i s b lack

INDEXP arkes

’

s gutta-

percha compound 391sur face colors 247

P armelee’s rubber cure 57

P ar them'

um arg entatum 17P assmore rec la im ing 298P aste rubbers , A fr ican 18

P au rubber 39

43P ay en

’

s ana lys is of gutta-

percha 397lead acetate patent 102P ectous rubber 308

P ed ry oid 133

P eg amo id 149

P enang rubber 25P ensa

’s rubber 132

P entane 241

P entasulph ide , A ntimony 68

P enther rec la im ing proces s 298

P epperm int oil 223

P erchoid 133

P ermanent wh ite 93 , 107P ernambuco rubber 16

P eroxide , I ron 185Hyd rog en 201

subst itutes 133

P eruvian rubber 13

P eter son rec laim ing 298

P etr ifite 107P etro latum 223

P etroleum j el ly 224

naphtha 240

o il 224

Rang oon wh ite 224

solvents 241

P henol 203

P hosphate of sod ium 209

P hosphorus 107

P hys ical testmg of rubber goods ,302, 337

A ir b rake and s ignal hos e 343Burst ing test of . 345Fr iction test of . . 344

P oros ity test of . 344

Stretch ing test of coverand tube of 344

Tens i le s t r e n g th oftube and cover of 344

Test spec imen of 343

Defects of test pieces for 343Set in 342

B ar test p ieces 343

R ing test p ieces for . 343

Standard methods of . 338

Temperature 339

Tens i le strength 339

Time 339

Tens i le strength determ inat ion 341

acros s the seam. 342

0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0


413

P hys ical testing of rubber

g oods—Continued .

Tens i le strength—Continued .

A pparatus for 341

bar test pieces for ,Marking 341

Measurement of 341B reaking 341

breaking pomt E longation at 342

Gr ips 341

.

r ing test p1eces 341, 342r 1ng test pieces , M eas

urements of 341test pieces , P reparation of 339A verag es 339

E long at ion 339Fr iction 340

Sampl ing 338

Set 339

P ickeum gum 41

substitute 133

P icradenia flor ibunda utilis 41

P igments for color ing rubber 176

P ine o il 244

P inus lentis cus 175

maritima 175

palus tr is 175

S y lves tr is 244

P ioneer m ineral rubber 131

P ipe c lay 108

P istacia lentiscus 175P itch 169

Black 158Burgundy 158

Coal ite 160

Jews 155

Natura l 167

Stear ine 173

Veg etab le 175

P ithecolobium big emmum 207

P lantation rubber 27Forms of 31

B i s cuit 29

Block 30

Crepe 29Flake 30

Lace 30

Sc rap 30

Sheet 29

Worm 30

H evea , O ptimum cure of 71

M arket names of 30

Amber c repe 30

B rown c repe 30

Ceara 31

Central Amer i can 31

Ceylon Casti lloa 31

Columbo sc rap 31

414

P lantation rubber—Continued .

Market names of—Con.

Congo 31F irst latex crepe 30

Guayaqui l Castil loa 31

Java Cas tilloa 31

M exican 31

Rambong 31

Smoked Sheet, pla instandard qual ity . . 31

r ibbed s t a n d a r dqual ity 30Tobago 31

Tr inidad 31

Uganda 31

Un s m o k e d Sheet,standard qual ity . 3 1

West Ind ies 31

Wor ld’s A nnual production of 28

P laster of P ar i s 108

P laster s , Compounds for 375Manufacture of 375

P lasticon 150P lastite 150P lumbag ine 108

P lumbago 108F ono l ith 189

P ont ianak rubber 26

P res sed 26

Refined 26

P oppenhusen rec la iming process 295

P oppyseed oi l 224

P ortland cement 109

P otash 204

caustic 205

P otass ium ac id tartrate 204

arsenate 204

b ichromate 204

b i sulphate 204

carbonate 204

cyanide 205

hydroxide 205

permanganate 205

P otato cel luloid 150P ouckpong gum 42

P owdered coal 109

P ozel ina 49

P ratt Vulcabeston 152

P reserving rubber goods , P rocesses for 257

Benton’s 258

E lworthy’s 258

Kreusler and Bude’s 257

Mowbray’s 258

Trueman’s 258

Truss’

259

under"

water 257

Zing ler’s 259

INDEX0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0




0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


QUERCUS infectoniaQuickl imeQuinn’s rubberQuittah n ig g er s rubber

RAM BONG plantation rubber 31

Rangoon rubber 25

Rapes eed oil 215, 224

Rate of cure of plantat ion P ara

rubber 73, 311

P resspahm 150P res sure cure 62

P r ice (Amer ican) rec la imingprocess 298

(Eng l ish) r e c l a 1mingproces s 298

P r ince’s metal l ic pa in 185P r int ing on inflatab le rubberfi lms 248P roofed fabr ics , Compounds for 364

Manufacture of 364

O rnamenting 248P ropert ies in rubber , Relat1on

sh ip of mechanicalto chem ical 345

Depolymer izat ion 346

O pt imum cure 345Stres s - stra in type curve . 348

P ropylene ch lor ide 244

P rotoch lor ide, Sulphur 68

P rus s ian b lue 181

red 185P um ice 110

P uncture fluids and ti re fi l ler s 266

Campbel l and Cushman S 266

Cellazote 267

Cy co 266

Dow’s 266

E lastes 266

Ever lasti c 266Fag iol i 266Frankenburg 266

Inr ig 266

N ewmastic 267

P uncture Closer 267

Roland’s 267

Rubber foam 267

Rubber ine 268

S cott’s 268

Suber’s 268

Tire Li fe 268

P urcel l ite 133

P uruh 49

P urus rubber 12

P uzzolana 110

P yroxyl in 150

P . F. U. gum 41

INDEX416

Rotten stoneRouen wh iteRoux rec la im ing proces s

Rubber , A ct ion of metals on . .

A dhes ive pr inc iple o f

c rude 8

asphalt 135

Calender ing 353

cements 372

Chemical formula of 8, 271

Coeffi c ient of vulcan1zat ion and the stateof cure of 347

colors , Requi rements for 249Deodor izat ion of 256

E lectroplat ing on 248

Emboss ing of 248

flux 135

foam 267

g ood s , P h ys ical testing of 337

g rades , Crude 10

Harr ies formula for . 271

Impregnat ing 251

I nsolub le mattei in 309

latex 8

A dulterat ion of 34

A nalys is of H evea 44, 266

maker s’

wh ite 189

manufacture 354

Divis ions in 354

Boots and 357

Cement 372

Dental a n d stampgum 373

Drug g i sts .

’station

ers’

and surg ica lsund r ies

Hard rubber

Insulated w i reMackintoshes , proof

ing and carr iag ec loth 364

M echanical goods 354

Mold work 369

Notions 374

P lasters 375

Ti res 366

P r imary proces ses in 351

Calender ing 353

Drying 352

M i l l ing 353

Spread ing 354

Wash ing 351

N ervy” pr inc iple in . .8, 308

N itrog enous sub stancesin 309

O il subst itutes for 117

A nalyses of 118

O ptimum cure of 346

0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


o o o o o o o o o o o o o o o o o o o o o o o

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0

O O O O OOO O O O O O O O O O O O O O O O O O


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Rubber- Continued .

P hys ical propert ies of 7

p igments 176P reserving goods 257scrap 292

Shr inkag e of 263

Solub i l ity of (tab les ) ,228 229

res ins (tab les ) 229

solvents 230

Sources of 7Spec ific g ravity of 265, 349Synthet ic 274

tree, Male 43“Type” curve of crude 348

Uniting metals to 259Valuat ion of crude 303ve lvet 135

Rubberaid 135Rubber ic 135Rubber ine 268

Rubber ite 135

Ruber ine 135

Rubero id 135

Rub -h ide 136

Rus s ian m 1ueral 0 11 225

S AL ammoniac 206

soda 206

Saleratus 206

Sa l icyl ic ac id 206

Salol , vulcanized rubber solvent . 329Salt 49 206

Rec laim ing 206

Saltpeter 206

Salt- pond rubber 20

Sandarac gum 171

Sankuru rubber 22

Santos rubber 16

S apium big landulosum 42

tolimense 15

S apotacea' 377

Sarawak 26

Sarco 136

Sarua rubber 41

Satin g loss b lack 180

Saxon b lue 181

Schidrowitz, exam inat ion of crude

rubber 307

and Goldsborough on co

effi c ient of vulcanization and stateof cure 348

stress stra in type curves 348S cott’s puncture fluid 268

Seed lac 171

Se iba gum 41,42

INDEXSelen ium 111Seneg al gum 171Ser inguina 49Sernamby P ara rubber 10, 11

Shale, A rg i l laceous red 90oi l 225spi r it 244

Sharpe, A nalys is of gutta-percha

397Compos it ion of gutta

percha by 397Shea butter 38She l lac 171Shepard

’s gutta-

percha compound 390Showerproofing 251

Amer icanCohuru

’s 255

Cravenette 251Eng l i sh 253Forster’s 254F rankenburg

’s 255

German 252, 254Kyanized 254

Sm ith’s porous 255

Shr inkag e of c r u d e rubber

(tab les) 263, 264

S ierra Leone rubbers 20

S i lex 111

S i l icaS i l icate, Carbon b lack 180

Cotton 111

S i l icon flour ide 206

S i lky A ss inee rubber 20

S i luminite 150

S imond’s rec la iming 295

S impson’s rubber cure 57

S inapis alba 221

nig ra 221

S ize 172

S lag wool 111

S laked l ime 111

S late 111

S ludg e oil res ins 173Smalts 182

A nalys i s of (tab le) 182

Sm ith’s , Thos ., Theskelon cement 136porous fab r ic shower

proofing 255

Wi l loughby, gutta-

per

cha compound . 152, 387

50, 206bark 207

Cast i le 207Res in 207subst itutes 136

Soapstone 111

Soda 207209206

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0




0 0 0 0 0 0 0 0 0 0 0 0



417

Sod ium b iborate 207b isulph ite 208carbonate 208ch lor ide 208hyd roxide 209hyposulph ite 209

phosphate 209s i l icate 210sulphate 210

tung state 210Sol igum 136Solub i l ity of rubber (tab les) .228, 229

of rubber res ins (tab les) . 229So lub le g lass 210Solvent, Chute’s rubber res in 236

Gottsch’s vulcanized rub

ber

Twis s’ vulcani zed rub

ber 328

228Methane 239P etroleum 241Rubber 230Vulcanized rubber 328

Sorel’s compound 103 151Soudan rubber 19Spanish wh ite 189“Spec ial” b rand ZlnC oxide 190

Spec ific g ravity, Determination of 350in rubber compound ing . 349of rubber 265of petroleum n a p h t h a

(tab le) 241

Spec ificat ion, Th irty per cent.H evea insulationcompound 333

Spence, color in crude rubber 52“O n the Relationsh ip of

M e c h a n i cal to

Chemical P ropert ies” 345oxy dazes in crude rub

ber 52rec la iming process 299

Spermacet i 173Spi l l’s gutta-

percha compound 389Spind le rubber 24

Sp i r its of turpent ine 245of wine 50Wood 246

Spread ing rubber 354Spruce gum 173St. Georg e turpent ine rubber 138Stab i l it 151Starch 112

Stear ine 173 225

pitch 173Steenstrup

’

s rec la iming proces s . 298o

418 INDEXStevens , coeffic ient of vulcanizat ion and the state


of cure 347Stick rubber 24

Sticklac 171, 173Stockholm tar 173Storax, Bal sam of 156Straits rubber 29Strasburg turpent ine 158Subers

’ fi l ler 268

Sub l imed lead 112

Submarine cab les , Insulat ion of . 387Subst itute, B landy ’s 120

B rown’s hard 143

Carbon b isulph ide 235Dankwerth

’

s 122

De P ont’s 145 q

F ayol le’s 124Frankl in 125

German b lack 120

Gr iscom’

s 125Harmer’s 126

Jones’s 127

Moroccol ine 131

Nature and use of 117Nig rum E last icum 131

Novelty rubber 131

O hmlac 132

P aragol 132

P edry oid 133

P erchoid 133

P eroxide 133

P ickeum 133

P urcell ite 133

Resol ines 134

Russ ian 136

Soap 136Tong oil 137Wichman’s 139

Wolfert’s 139

Sug ar of lead 112, 202

Sulo 136

Sulphate, Sod ium 210

Sulph ide , Lead 68Z inc 69

Sulphur 69Balsam of 69, 156

bath cure 63

ch lor ide 65fumes 50

Honeycomb 67

Liver of 68

lotum 69

M i lk of 68

Sulphuret, A nt imony 66

Sulphur ic ac id 210

Sumatra rubber 29

Sur face co lors 247

pr inting 247

O

Susu-

poko gum 41Synthet ic ru-bher 269

Avai lab le sources of 273Butanes 272Ear ly invest igations on 269d imethyl butanes 272H istory ofI soprene 271 272P ract ical uti l ity of 273P roduction of 270

TAB B Y ITE 136Taberncemontana Thurs ton: 41Talaing rubber 41Talc 112Tal ite 112Tal low 225

M ineral 166Talotalo gum 41Tamatave rubber 24

P inky 24Tanni c ac id 211Tannin 211

174B irch bark 157Cand le 159oil 226Stockholm 173

Tarpaul in compound 102Tartar ic ac id 211Tava rubber 23Taylor’s P urcel lite 133Terra-verte 183

A nalys is of 184Tetrach lor ide , Carbon 235, 244Tetrachlormethene benzene sub

stitute 244Texoderm 151Textiloid 137Theilgaard

’s rec laiming proces s . 298

Thenard’s b lue 182

Theskelon cement 137Th imb les , A fr ican 18Thion 244Thomas

’s rubber cure 56

Thus , Gum 174Thyme oil 226Thymus vulg arzs 226Tin oxide 113

Tire Life 268Ti res , Compounds for 367

Manufacture of 366Tirucal li gum 42

Tobago plantation rubber 31

Togoland rubber 21

Tolu bal sam 174Toluene 245

420

Vulcanization —C0ntinwed .

INDEX

process of—Continued .

H enr is’Hot

Joselyn’

s

Marcy’sM eyers’Mul lee

’s

Murphy’sNewbrough and F a

g an’s 64

N ewbrough’

s 57N ickel

’s 60

O l ivier’s 61O stromis lensky

’s 275

P arkes’, A lex. 59P armelee’s 57P ressure cure 62Raymond

’

s 61R ider’s 58S impson’s 57Sulphur bath 63Thomas

’56

Trotter’s 55Ultra-vio let rays 61Vapor 54, 59Wi l lman

’

s 57without sulphur 275A cce lerators for 282A g ents for 287benzoyl peroxide . .283 , 284mechani sm of 280nitroso c o in pounds

(tab le) 288org anic p e r o x ides

(tab le) 289P atents for 285, 287

peroxides 282tr initrobenzene .277 278Vulcanized rubber analys is 312

A ni l ine method for m in

era l fi l lers in 323Bureau of S t a n dmethods for

insulat ion, 30 per

ards’

.312, 314cent.

P ara 319acetone extract 319alcohol ic potash extract 320ash 320calculations 320

ch loroform extract . . 320free sulphur 320

g eneral 319total sulphur 320unsaponifiable mat

ter 319

waxy hydrocarbons . 319mechanical g oods 315

o o o ooo o o o o o o

0 0 0 0 0 0 0 0 0


O O O O O O O O O O O O O

0 0 0 0 0


Vulcanized rubber analys i s— Conacetone extract 315a lcohol ic -potash extract 318ash 317barytes 317calculat ions 318free sulphur 316spec ific g ravity 318sulphur of ash 317tota l sulphur 316

outl ine plan 312

preparat ion of samples 314g r ind ing 314hard rubber 315soft rubber 314reag ents 315acetone 315a lcohol ic potash 315bar ium ch lor ide solut ion 315fus ion m ixture 315nitr ic ac id -bromine 315remarks on 312acetone extract 312alcohol ic potash extract 314ash and sulphur in

ash 313barytes 13ch loroform extract 14

free sulphur 313rubber 313spec ific g ravity 314total sulphur 313

E lectro lyt ic methods for 332Lead 332Z inc 332

Jo int Rubber Insulat ionCommittee’s method s for 321

calculat ion 321

outl ine plan (tab le) 322Mt. P rospect Laboratory

methods for 329alcohol ic -

p o t ash extract 330free sulphur 329m ineral fi l lers 329rubber by we ight 330

by volume 330Rubber by wet .combust ion 324

Solvents for 328, 329

Sulphate sulphur method 328Sulph ide sulphur meth

0 d 326, 327Vulcaniz ing ing red ients 63

pressures (tab le) 70

INDEX 421

Vulcanizing ing redients—Continued .

processes 54

temperatures (tab les ) 78246

WALNUT oil 226

Wamba rubber‘ 23

Washers , Unvulcanized packing . 138

Wash ing rubber 351

Waste rubber , Grades 293

Sources of 293

Wax ,A nt 40

Bees 156

Candel itta 159

Carnauba 159

Earth 161

Japan 217

M inera l 167

P araffi n 168, 223

Weber , Dr . C. 0 , analys is of XANTH ORRH OEA A rboreavulcanized rubber 312 A ustralis

cel lulose compound 152 gum

Wesson and Knor r , rubber bywet combust ion 324 X elton

West Ind ian rubber 16 Xingu rubber

Wet heat cure . 54 XyleneW’

halebone , A rtific ial 141 Xylo id inWhaleite 139 XylolWheat flour 113 Xylonite

rubber 139“X X

”brand z inc oxide

Whee ler’s rec la iming process . 298

Wh ite, Bar ium 187Becton 187

B lane fixe 186'

i

Boug ival 187

Calam ine 187o o o o o o o o o o o o

G lar lton 187o o o o o o o o o o o o o o o o

Chines e 187o o o o o o o o o o o o o o o

Constant wh ite 186Fard’s Spanish 187Fulton 188

188o o o o o o o o o o o o o o o o

Kremnitz 188

lead 113

L ithopone (l ithophone) 188

bf orat 188

Mondan 188

O leum 188

O rr’s 189

pigments for 186

F onol ith 189

Ross’

s 189

Rouen 189 ZA CK I NGUM M I

Rubber Maker s’ 189 Zea may sSpani sh 189 Z inc borateTroye’s 189 carbonate

Wh ite—Continued .vi tr io l 114Z inc borate 187carbonate 189oxide 189sulph ide 191

Wh iting 114

Wichman’s substitute 139Wickham’

s mach ine 51Wi l lman

’s rubber cure 57

Winthrop gum 139

Wither ite 114Wol fert’s subst itute 139

Wood ashes 50sp ir it 246

Wood ite 139

Wormwood oil 227Wray’s gutta-

percha compound ,152, 387

YALE blueYel low, A nt imony golden sul

phideA rsenicA ureo l inBarber ryCadm iumCarselChrome

CobaltDutch pinkGambog e

guttaocher

pigments for rubberTurner

’sZ inc

422 I NDEXZ inc— Continued .

ch lor ide 69, 114iod ideoxide 114

,“Green SealRed Seal”Spec ia l” brandWh ite S ea l” brand . .XX” brand

sulphate

OZ inc Continued .

sulph idewh iteyel low

Zing ler’s Dermatine '

compound

preservat ion of rubber

goodsZ insser’s bar rel l iningZuhl

’

s rec laiming processZy lonite

ADVERTI SEM EN TS

Economy of Cost and Strong e r Rubber

Besides

se of hand ling

curacy of

e igh ing

ving of waste

there is

further great

antage of

ick M ix ing

he granulatedtic le s are ah

bed so quicklythe rubber and

pounds , and so

st the process ,

t mixing is com

ted in abouthalfusual time .

his gets the rub

off the mill ine to savemuchof

disruption oftheeswhichdetracts

much from the

ngthofthe gum.

y using Granulated M.R.X . you save time andnger rubber. Samples and price on application.

Standa rd Emarex Company5 Mad ison Avenue -NEW YORK

ADVE RTI SEM EN TS

B RA NDS

The Resu lt of 3 4 Y ears Con

s istent P rog ress and Deve lopment

U. S. RUBBER RECLAIMING CO.,Inc.

42nd ST . BUILDING , NEW Y O RK

INDEX O F ADVERTISERS

A cushnet P roces s Co.

A lum inum Flake Co .,The

A stlett, H . A . Co.

Binney Sm ith Co.

Bi rm ingham I ron FoundryBuff alo Foundry Mach ine Co.

Butcher , L. H . Co.,Inc .

Cabot, Samuel , Inc . Ins ide FrontCanfield O il Co.

,The

Carter Be l l Manufactur ing Co. , The

Connecticut M i l l s Co .

Continental Rubber Co. of New YorkConsulting Co .

, The

Coul ston, J . W. Co.

Cutler , David A .

Day , J. H . Co.,The

E ag le- P itcher Lead Co ., TheFar r el Foundry Mach ine Co.

F razar 8: Co. O ppos ite Ba’

ckH ender son

,F. R . Co .

Hog g son "’

P ettis Manufactur ing Co.,The

I nd ia Rubber P ub l ish ing Co ., The 10,15, 17, 28, 37

Loewenthal,R . M . Co.

Manhasset Manufactur ing Co

Maywald , Fr eder ick J. , F . C. S .

O balski Sweeney, I nc .

P h i ladelph ia Rubber Wo .ks Co.

Rare M etal P roducts Co .

Raven M ining Co. of UtahRoess ler 81 Hass lacher Chem ical Co.,

The

S cheel , W i ll iam H .

S chrader’

s , A . Son, Inc . 42.

Scott, H enry L. Co. Ins ide Back CS eaver Co.

Somer set Rubber Reclaim ing WorksStam ford Rubber Supply Co .

,The

Standard Emarex Co.

Str esen-Reuter H ancock, Inc .

Tag l iabue, C. J . Manufactur ing Co.

Taylor , A rm itag e Co., Inc.

Ty pke King ,Ltd .

Tyson B rother s , I nc .

U. S . Rubber Reclaiming Co ., I nc .

Waldo, E . M . F. O ppos ite Ins ide Front CWeber , Lothar E .

,Dr .

West, H . T. Co .,I nc .

VVestmoreland Chem ical and Color Co The

W i l l iams, C. K . Co .

Wood,Char les E .

ADVERTI SEMEN TS

LOEWENTHALI NCO RP O RATE D

c r ap

u s 1ve y

spec ialists in our line w e plac e

at y our d isposal expert s ervic e bas ed

on y ears of“know ing how

”

,and

g ua r ante e s b a cked by r eputation

You li’viiii’i iAuto ScrapWe{Iii/

“I

East 42nd Street New Y ork

ADVERTI SEMEN TS

A ND

KINDRED PRODUCTS

Importe rs and Trade r s B u ild ing

P ear l Street NEW YORK

81 ll 0B y HENRY C. P EA RSO N,

The most in forming story o f the B raz il ian rubber centers everwritten .I t reflects intimate knowledge , based on years of study, and

the observations and experiences during the writer’s several visitsto the A mazon country .

A fter being a rubber manu

facturer, and for 25 years awriter on rubber ; after trave l ing through the rubberp lanting belt around t h e

world , and visiting all thep lantation centers of b’I ex ico,Central America and the F ar

East , the author spent a winter in the ‘ country of the

A mazon,leisurely traversing

the course o f that great riverfrom P ara to M anaos andbeyond .

He describes the country,its flora and fauna ; its peop le and thei r customs ; therubber forests,the gatherer’s

l i fe and methods,and theprocesses of tapping and co

agulating . He covers the

upper Amazon and its tributaries and describes the rubber interestsof B ol ivia , P eru, Colombia , and o f A cre— the richest rubber territory in the world .

In addition to thi s , the book deals with the various phases ofp lanting,gathering and marketing of rubber, and will be found botha h igh ly instructive and very entertaining narrative of a section ia

timately known to few, but of great and increasing interest to many .P rofus ely I llus trated

P R I CE 3 0 0

P U B L I S H E D B Y

The Ind ia Rubber P ublishing,

Company25 We st 45th Stre e t, New Y ork

Continental RubberCompany ofNewYork

GUAYULE RUBBER

Usua l Good Qua lity

20% Shr inkag e

CIRCLE BRAND

P ARRA BRA ND

120 B roadway , New Y ork

c ient 1c reatment

Reclaiming of F ricti on Scrapfor

T h e T r a d e

ACUSHNET P ROCESSN EW B E D F O RD ,

M A S S .

Wa shed and Dr ied

Re ady for

Compound ing

TRIANGLE BRAND

DURO BRAND

ADVERTI SEMEN TS

M a nuf a c tu r e r

M ED

S TA NDA RDIZED QUA LITY

N EW Y O RK

5 2 VA NDE R B ILT A VE .

P H ILA DELP H IA ,

A KRO N , O H IO LA ND T ITLE B LDG .

13

14 ADVERTI SEM EN TS

THAT HAS STOOD

THE TEST FOR YEARS

Spec ia l GRA DE S for the fo llowing TRA DE S

Insu la ted Wire

B oo t and Shoe

Mechanica l— Au to Tire

P roofing

Hard Rubbe r

We will cheerfully furnish samples upon request

SOMERSET RUB B ER

RECLA IMING WORKSNew B runswick

,N. J.

F a cto r y— Ea st M ills tone , N. J., Some r s e t County

16 A DVERTI SEM EN TS

Un ique Co lors E spec ially Mad e

Rubber Makers Use

Blacks

Reds

Yellows

Browns

pr inc ipal rubber manufacturers in the

United States , E urope and Japan use thes e colors .

S end for samples , pr ices and particulars .

B inney 81 Sm i th Co .

SO LE M A KER S

N ew Y ork City

Rubber

Compounds

Pneumatic anSolid Tires

Inner TubesRubber

Composmons

Soles

Heels

Leather

Substitutes

etc.

ADVERTI SEMEN TS

REG. U. S . P AT. O F F .“ REG. UN ITED KINGDO M

P ub l i she d on the l s t o f e a c h month b y

THE INDIA RUB BERWORLD

NEW YORK

E dited by

H E NRY c . P E A RSON , F .R .G .

STA B LI SHED in 1889 , to represent the interestsmanufacturers and distributors of india rubber and allied

goods in the United S tates , this j ourna l has broadened its scopeuntil it now commands a position of importance as a record ofthe rubber trade and industry in all other countries as we l l . A t thesame time it has taken a leading position as an exponent of therubber-planting interests and the intelligent exploitation of forestrubber

,while its statistical department is more fully relied upon

than any other source of in formation of this class .The publishers believe that to-day no other special j ournal

published covers its field so fully, or commands a circulation sowidespread or of such a high character. The contents of TH EI NDI A RUBBER WORLD are

,for the most part , expert informa

tion , covering whatever is new in factory processes , in . rubber

machinery, in applications of rubber , in company developmentor changes

,market conditions

,and whatever e l se may concern

the entire field of rubber interests .A s an advertising medium ,

it is believed that the paperoccupies an exceptional ly high position as a medium for bringingmanufacturers and consumers of rubber goods into contact, andfor attracting the attention of manufacturers to new appliancesand materials .

YEA RLY SUB SCRIP TIO N

UNITED STA TES A ND MEXICO ,

A LL O THER COUNTRIES ,

17

S ta nd a rd s o f Ex c e l len c e -a nd Ef f ic i en c y

ime te

ue(B a s ic Sulphate -Non -P o isonou s )

W e shall b e pleased to quote

d e l ivered pr ices anywhere in the

United States and for E xport.

W arehous es ma intained in a ll

pr inc ipa l c itie s , insur ing prompt

s ervic e .

G E N E RA L O F F IC E S

208 S . LaSa lle Stre e t CHICAGO

E X P O RT D E P A R TM E N T

10 1 P a rk Avenue NEW YORK

P LA NTS

JO P LIN, MO . CINCINNATI , O . NEWARK, N. J.

{E s ta b l i s h e d 1882

120 M i lk S tree t , B os ton , Mass .

A n inert pigm ent wh ich

sm ooth es and toug h ens

tire compounds and .mate

r ially les sens c laim s for

adjustm ents

E qua lly adapted to other

c om pound s W h ere du ra

b i l ity and r es i l iency a re

required

22 A DVE RTI S EM EN TS

COLORS MINERALS CHEMICALS

We are in pos ition to supp ly promptl y , at

attrac tive pric es , the fo l low ing m aterials , bothin car load s from m ill or less car loads frome ither Chicag o or C leve land stocks :

LITHOPONE

ZINC OXIDE

WHITING

MAGNESIUMCARBONATE

OXIDE

HYPOBLACK

WHITE

LITHARGE

We A ssur e P r ompt and Efi’

czient A ttention to

A l l I nquir ies , La rge or Sma l l

Ma in O ff ic e

CH I C A G O

Branc h e sCLEVELA ND NEW Y O RK DETRO IT

TO RO NTO P H ILADELP H IA

IRON OXIDES TALCALL GRADES

BARYTESSULPHURREFINE )

BLANC FIXECOMMERCIAL GILSONITE

ANTIMONY SULPHURET ANILINE OILGOLDEN

CRIMSON COLORSCHEMICAL

CARBON BLACK MINERAL

LAMP BLACK BENZOLE

H . T . WEST CO .,I N C.

148 STATE ST. B O STO N , MA SS . Cable Address:Westant

M a nufa c tur e r s a nd Dea le r s

P roductsDisti l lates , Compound s

Res iduums , P itc hes

O i ls and Waxes

R e f ined , s tand ard ized , s e le c ted fo r

In6 ar8 ind iv id ual requ ireme nts

P ur e natura l g as p ro d uc t , o f h ig he s t s tr eng th and un ifo rm ity ; f re ef rom o i ls

D i r e c t d is t i l late s and c ompound s

to m e e t any spe c if ic ations as to

vi s c o s ity , c o lo r and ro s in ac id ity

RO S IN GUM TUR P EN T IN E CA N DLE T A R

P I N E O IL W O O D TUR P ENT I N E P A RA FFIN E W A XE ST A R O I L CRUDE TUR P ENT IN E P ETRO LEUM O ILS

GUM THUS VEN ICE TURP EN T IN E CO TT O N SEED O ILS

P IN E P ITCH BURGUNDY P ITCH VA RN I SHE S

S h ipm ents in any qua ntity d ir e c t fr om p o ints of pr od uc tion o r

fr om loca l s to cks

26 ADVERTI SE IVI EN TS

THEWESIMOREIAND0HEM|0AI AND00101100MPANY

P H ILA DE LP H IA N EW Y O RK

9 2 5 C h e s tnut S tre e t 9 2 W i l l iam S tre e t

O r i g ina l M a nuf a c tu r e r s in th e Un i te d S ta te s o f

REDOXIDES OF IRON

TRA DE M A RK

The best compounding, coloring and covering values for the money

STRIOTLY PURE AND IMPALPABLY FINE

W e M a n u f a c t u r e a V a r i e t y o f S h a d e s o f

R E D O X I D E O F I R O N

P a r ti cu la r l y A d ap te d fo rRubber M anufactur er s

’ Us e

Extreme l y s trong in co lo r ing power andg round impa lpab l y fine . A l so variousg rade s o f Ta lc , S oap stone and A sb e stine . Write us for s amp l e s and price s .C . K. W ILLIAMS 8: CO .

EA STON . P A .

A ldehyde Ammonia (Cry stals ) .

F ormaldehyde U. S . P . 40 P er Cent. Volume.

Formanilid .

Hexamethy lene Tetramine (P owdered ) .

Sulphuret of A ntimony— Golden

,Crimson,

Vermilion.

THE RO ESSLER HASSLACHER CHEMICAL CO .

Wi lliam Street New Y

A l u m i n u m F l a k e

The Colloidal P igmentwhich Vitalizes the Compound

P ro no unc e d b y e xp e rts to b e

The Ideal Rubber Compounding Ingredient

Low e s t in S p e c if i c G r avity H i g h e s t in Q ua l ity

14 y e a r s'

p e r s i s te nt u s e i n rub b e r m i l ls a l l ove r th e wo r ld its b e s t e nd o r s e m e nt

THE ALUMINUM FLAKE CO AKRON, OHIO

A R IA L B RA N DS

RUB B E R S UB S T ITUTE A N D

C H LO R IDE O F S ULP HUSuper ior Qual itie s . m ad e from b e s t mater ial s and b y up

-to-d ate me thod s .

Wh ite Sub stitute . BlackSub stitute . Mono Ch lor id e Sulphur , for makingWhite Rubber Sub s titute . P roto Chlor ide Sulphur , for cur ing purposes .

B i-Chlor id e Sulphur, for making Brown Rubber Sub stitute .

A lso Waxes and E arths . Tr ial orders sol ic i ted .

W I L L IA M H . S C H E E L

15 9 M a id e n La ne a nd 3 7 F le tc h e r S tr e e t , N e w Y o rk, N .

THE INDIA RUBBERWORLD

NEW YORK

E dited by

H E NRY C. P E A R SON , F . R . G. s .

YEA RLY SUB SCRIP TIO N

UNITED STA TES A ND MEXICO ,

A LL O THER COUNTRIES ,

ADVERTI SEMEN TS

Bos ton Yarn Company

BO STON, MA SS.

So le Se llin g ‘

A g e nts fo r

STATE COTTON CORPORATION

Manufa c tur e r s o f

AUTOMOBILE TIRE FABRICS

Sea Islands, Egyptians P eelers

LOWELL, MASS. LEROY, N. Y. NEWBURYPORT, MASS.

C O N N ECT IC UT M I LLS A N D O P E RA T IV E S'

H O M E S .

OII IIQQIICOI omponvM A N UF A CTUR E RS O F

F IN E S EA IS LA ND , EGY P TIA N A ND

P E E LE R TIRE F A B R IC S

O F F IC E R S

TRA CY S . LEW IS . P R E S . 8: TR E A S . R . J . C A LDW E LL . V .-P R E S

H A R RY L . B UR RA G E , C H A I RM A N O . B UTLE R . S EC .-M GR .

R . L . F IS H E R , A S S T . TR E A S

P LA N TS

D A N I E L S O N . C O N N E C T IC UT

T A U N T O N . M A S S A C H U S E TT S

1 5 P A RK R o w N E W Y O R K

32 ADVERTI SEMEN TS

TRA DE M A RK

“Qui n t on

The F abr ic for Endurance

MANHASSET MFG. COMPANYP rovidence Rhode Is land

Perfect Vulcanization

is the m os t vita l fa ctor in the m anufacture . o f rubb er g ood s ,

b e cau s e the qua lity and cost of the fin i shed p roduct d ep end ab so

lute ly up on the un iform ity and dur ation of the cure

TAG A utomatic Control le rsa re recognized a s stand a rd equ ipm ent in rubbe r p lants a ll ove r the wo r ld be c au s eo f the ir super-human a c cu ra c y in a utom atic a lly m a inta i n ing p rop e r tempe ra ture

and time in vu lc an iz ing.O u r d om ina tin g p os ition in the rubbe r fie ld adm irab ly q ua l ifie s u s to

economica lly and eflic iently s o lve y ou r tempe ra tu re p rob lem s .

Cata lo g s and e xp e rt advi c e g lad ly offe re d to tho s e inte r e ste d .

Largest IndependentM anufacturers of A utomatic Con

.trollers , Thermometers , etc . , for the Rubber Industry

B RO O KLYN, N. Y. CH ICA GO B O STO N NEW O RLEA NS“

SA N FRA NCI

AlDVEKTl S EM EN TS

Absolutely Dries Without Injury All Kinds of

Rubbe r and Compounds

SH ELF DRYE R W ITH VACUUM P UM P A N D CO N DE NSE R

B uflovak Dry ers represent “The H ig he s t A tta inme nt

Va cuum Dr y e r Con s truc t ion .

” I n our Shelf Dry ers , the bodyof the Dryer , even on the larg est s izes , i s made in one piece of ourspecial “GUN I RO N metal

,thus eliminat ing the numerous j oints

found in other types and insuring the maintenance O f a hig h vacuum .

The “B utlovak”

Rotary Dryer used for dry ing rec laimed rubber,compound s , and other material s , i s noted for its rigid construction ,

h igh efficiency, and low Operating cost . O ur catalog showing theseand other Vacuum A pparatus wi l l be sent on request .

Buffalo Foundry Machine Co4 6 Winche s te r Ave . BUF FA LO , N. Y .

33

34 ADVERTI SEMEN TS

CA LENDERS , M ILLS , RE F IN ERS , SHEETER

CRA CKERS , WA SHERS , P RESSES , HO SE MA CHI

ERY , HA RD RUB B ER MA CH IN ERY , DRIVE

SHA FT ING , F R ICT ION CLUTCHES , ETC .

E ng ine e r s a nd M a nufa c tur e r

FARREL FOUNDRY SI MACHINE C

A N SON IA , CONN . , U. S . A .

C ab le A d d r e s s : F A RRELM A CH— A N SO N I A

B ranc h O ff ic e : 910 UN IO N N A T IO N A L B A N K B LDG C LEVE LA N D ,

36 A DVE RTI S EM EN TS

E s tab li she d 183 6 In c o rpo r a ted 1850

WASHERS , MILLS , REF INERS, CALENDERS

HYDRAULIC AND SCREW P RESSES

ACCUMULATORS

CHILLED AND SAND CAST ROLLS , GEARING, ETC.

So le B u i ld e r s o f

SCHO F IELD P ATENT B IAS SHEARS

BANBURY AUTOMATIC RUB BER MIXERSB IRMINGHAM

”TREAD MAKING MACHINES

Spec ial Machinery B uilt to O rde r

B IRMINGHAM IRO N F OUNDRDerby , Conn . , U. S . A .

RUBBER M IX ING MA CHINER

We m anu fa ctu re Rubb e r Chum s fo r a ll c la s s e s 0

w o rk, and in a ll s i ze s , Heavy M ixe r s e sp e c ia lly ad ap teto Ti re m anu fa ctu r ing ,

m ix ing m a chine s fo r d r y m ate r ia l

Sc re e n s , B o lting Re e ls and Ra cks o f a ll kind s .Wr ite fo r ou r ca ta lo g s .The J. H. Day Company

CINCINNATI , O HIO

NEW YO RK PHILADELPH IA B O STO N KANSA S CITY CHICAO

A I ) VERTI S EM EN TS

An Ency clopedia of Machines Us ed in Crude Rubber

Washing , Dry ing , P reparing of Ing redients , Mixing

P reparing of F abrics , Calender ing ; Ty pical Vul

canizers , P res s es and Molds , Spreaders , Tubing

Machines ; Cements ; Rec laimed Rubber ; Ex

tracting Machines for Wild Rubber ; Labo

ratory Equipment ; Deres ination , etc ., etc.

B y HENRY C. P EARSON,F . R. G. 5 .

Ed itor of The Ind ia Rubbe r Wo r ld

This is the first author itative book containing com

prehensive descr iptions of the machinery used in prepa

ration of crude , compounded and r eclaimed rubber . I t

will be found an extremely valuable r eference work forrubber factory super intendents , master -mechan l cs and

eng ineers , etc .

The book is substantially bound in cloth, contains

4 19 pag es , 428 illustrations , and is conveniently indexed .

P r ice P ostpaid .

Descr iptive c ir cular and table of contents sent on

appl ication .

P UB LISHED B Y

THE INDIA RUBBER PUBLISHING COMPANY25 We s t 45th Stre e t, New Y o rk

AD I’ERTI S EAI EN TS

RUB B ER CH EM I ST

F REDER ICK J. M A YWA LD,F . C . S.

89 P IN E STREET , N EW Y O RK

F ormulas and processes modernized and standard ized . Costs reduced . P lans for lay-out of rubber factories . Experimental work for the manufac

turer, the inventor, the dea ler, in a ful ly equippedplant . A nalyses and physica l tests . Shrinkage tests .Experimental vacuum dry ing.

I have had many years’ experience in overcom

ing factory troub les , and have helped many rubbermanufacturers to correct errors in their methods andput thei r manufacturing on an efficient and economical basis .

Let us talk over y our prob lems .

P OLYGLOT

RUB B ER TRADE

DIRECTORYof the

United State s and Canada

19 16

This directory gives most comp lete and rel iab le informationthe entire rubber trade , properly classified and arranged to

faci l itate easy reference .The P O LY GLO T feature is a nove l one , enab l ing any onenot understanding Engl ish , but famil iar with F rench

, German ,Spanish , P ortuguese or I ta l ian , to avai l himsel f of al l the in formation as readily as though he read Engl ish .

The book contains the fol lowing :RUBBER GOODS M A NUF A C

TURERS

A lphabetical ly ar rang ed , with l i stso f offi cer s

,and clas ses of g ood s

made .

LI ST O F RUBBER MA NUF A CTURERS

Geog raph ica l ly ar rang ed .

I ST O F RUBBER MA N UF A CTURERS

Class ified by products .

RUBBER GOODS DEA LERSGeog raph ical ly ar rang ed .

CRUDE RUB BER I M P ORTERSBROKERSWA STE RUBBE R DEALERS

M A NUF A CTURERS O F RECLA I M ED RUB

LI ST O F

A ND

RUBBER FA CTORY SUP P LI E SRUBBER M A CH I N ERY

,TOOLS A N D A R

P LI A N CE S

RUBBER COM P A N I ES I NCORP ORA TED I N

TH E UN I TED STA TE SFrom January 1, 1915, to A pr i l 1,1916.

RUBBER TRADE O RGA N I ZA TI ON S I N

TH E UN ITED STATE SW ith date o f organizationnames of officers .

RUBBER TRA DE O RGA N I ZATI ON S , F ORE IGN

TRADE -M A RK S

N A M E S )Clas s ified by products .

and

(I NCLUDI NG TRA DE

Thi s directory should be on the desk o f every man interestedin the rubber trade . I t i s a mine of in formation,compiled witha view to thoroughness

,accuracy and simpl icity .

The book i s accompanied by addenda sheets , which bring upto date the l ist o f rubber manufacturing concerns .The vo lume is substantia l l y bound in cloth . I t wi l l be sentpostage paid to any address on receipt of or equiva lent funds

,per copy .

P ub li she d b y

THE INDIA RUBBER WORLD25 Wes t 45th Street, New York

F i g . 1

O ne-h a l f s ize

H E name SCHRA DER is a g uarantee of qua l ity. Th e

reputation wh ich th e produc ts of A . S CHRA DER’S SON ,

INC. , h ave acqu i red res ts upon s eventy-four years 0 1

e ffic ient s e rvi c e to th e trad e and pub l ic . S ince its e stab l ishment in 1844 the SCHRA DER firm h as had P ERF E CTI ON as

its watchword . S CHRA DER'

UNI VERSA L P NEUMA TITIRE VA LVES are th e re g ular equ ipment of more than n inetype r c ent. of a l l automob i le , motorcy c le and b icyc le ti re s mad e

in the Un ited S tates and Canad a , b e ing a lso extens ive ly us edb y T i re M anufacturers in F rance and Great B r ita in.

SCHRADER UNIVERSAL

TIRE P RESSURE GA UGES

A ls o oc cupy a pre fe rentia l pos ition in th e favor o f M otor ists .

F ig ure 1 s h ows th e GA UGE w ith th e s tand a rd b a s e mad e tc

fit TIRE VA LVES of th e A mer ican type . A S th is s tyle 0

GA UGE cou ld not b e us ed to measure th e inflation of ti refitted w ith th e E uropean s tyle T i re V alves . we have d es igne

a GA UGE w ith th e comb ination b as e (F i g . 2 ) wh ich ren

d e rs th e SCHRADER UNI VERSA L GA UGE appl icab le to a l

TIRE VA LVES . A s i l lus trated in F i g ure 2 , th e GA UGE ire ady for us e on E uropean type Va lves . F o r us e 0

th e S CHRA DER UNI ‘ ERSA L VA LVE , s imp ly uns c rew th

d etach ab le foot or s ocket.To m eet th e re qu i rements of th e U. S . A rmy w e hav

d eve lope d , in conjunction w ith th e S ig nal Co rps , th e GA UGi l lus trated (F i g . w ith b as e at an ang le of for meas u r in

pres s ures in pneumatic truck tires . O ftentime s th e free s pac

on truc k ti res b etween th e hub and fe l loe of th e wh ee l irath e r l im ited , b ut w ith th i s type of GA UGE th e pres sur

c an b e conven iently as c erta ined .

Th e ind icating s leeve of th e GA UGE 18 marke d to

m easur ing a i r pres s ures up to 170 lb s . and can b e us e d iconne ction w ith tires as la rg e as 8% in. in d iame ter .

F o r us e ab road ,we are prepared

to furn is h an ang le b as e g aug e o f th istype fitted w ith c omb ination b as e and

ind ic ating s leeve c a l ib rated in pound s

and k i log rams ,s im i la r to i l lus tration F i g . 3

(F i g . O ne-h a l f s i z e

S P E CI A LI S TS

IN A LL

CO LO RS F ILLERSA ND

CHEM ICA LSF O R

RUB B ER WO RKERS

HEA DQUA RTERS

RECO GN IZED STA NDA RDSand alway s alert to new

QUA LITIES of P ROVEN MER ITA lso

LARGEST AMERICAN PRODUCERS

MA GNESIA -MA GNES ITE

L. H. BUTCHER COMPANY,Inc.

E s tab l is h e d 1890

NEW YORK LOS ANGELES SAN FRANCISCO

on the date to which renewed.

TTAN

Co-Operation and s ervi ce have p laced F razar Com

pany in the enviab le pos it ion of b eing a lway s a s tepin advance .W e have an intimate know ledg e of our products andth eir functions .

O ur lab oratory i s conducted s o le ly for the s ervice of

the rubb er trade at larg e .W e are interes ted in y our prob lems and d e s ire 'to

co-operate .

F r azar 8: C O .

E s tab l ish ed ’

1856

Church Street N ew Y ork

Cqqrls and Pigments for Rubber"'compounding

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Transcript of Cqqrls and Pigments for Rubber"'compounding