Practical No. 1

DESIZING OF FABRIC

Desizing:

Desizing is the process of removing sizematerial from the fabric, which was applied duringsizing of yarn.

Objectives of Desizing:

o To remove the size material applied on fabricduring the weaving process

o To have a proper absorbency of water and dyesthroughout the fabric

o To reduce the consumption of chemicals insubsequent process

Apparatus:

i. Match Boxii. Stove

iii. Thermometeriv. Weighing Balancev. Measuring Flask

vi. vessel

Chemicals:

i. SandoClean PC (wetting agent)ii. NaCl

iii. Bactasol (MTN)

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Conditions:

i. Liquor ratio = 1:30ii. Temperature = 65-70 0c

iii. Time = 30-40 min

Procedure:

o First off all we took the sized fabric and thenweighed it.

o Then according to liquor ratio we took the waterand other reagents.

o Then we dipped the fabric in the solution of waterand other chemicals and then heated the water up to65-700c.

o We measured the temperature with the help ofthermometer.

o Tongs were used to remove the cover of the tub inwhich fabric was dipped.

o When 700c was achieved then fabric was dipped inwater for half an hour at this temperature.

o After half an hour take the fabric was took out andhot wash was given twice for 30 minutes.

o Then we gave it a cold wash and then the fabric wasdried.

Calculations:

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Fabric weight = 650g

Liquor ratio = 1:30

Water used = 650 x 30

=19500g

=19500/1000

=19.5 liter

Sandoclean:

Amount of the sandoclean = gramperliterxamountofwater1000

= 1gLx19500mL

1000

= 19.5 grams

NaCl:

Amount of the NaCl = gramperliterxamountof water1000

= 4gLx19500mL

1000

= 78 grams

Bactasole:

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Amount of the Bactasole = gramperliterxamountof water1000

= 4gLx19500mL

1000

= 78 grams

Note:

It should be noted that bactasole is enzymes and itworks only in acidic atmosphere. As pH of water is 7, but we required acidic atmosphere, i-e less than 7, co a small amount of acetic acid is used to create acidic atmosphere.

Starch Identification Test:

We put a drop of 0.5% iodine solution on the sized fabric and observed that blue colour was not obtained which indicates that starch was not applied as sizing material on the fabric.

Calculation of Size Removal percentage:

Original weight of fabric = 650g

Weight after desizing = 600 g

Size removal percentage= Originalweight−WeightafterdesizingOriginalWeight

×100

= 650−600650

×100

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= 7.69%

Conclusion:

o The desizing percentage shows that desizing is done appropriately.

o The chemicals break the starch into 3 sub portions such as glucose, maltose and oligosaccharide and thenremoved with washing in dye-bath at particular temperature.

Precautions:

o Glassware apparatus and open saturator should be washed properly.

o Use lab coats in lab to avoid from action of chemicals on clothes.

o Use gloves to avoid from action of chemicals on hands.

o Harmful chemicals should be treated carefully otherwise they can damage the skin.

o Chemicals should be weighed accurately otherwise goodresult will not be obtained.

Review Questions:

i. Why Sandoclean DTC and NaCl are used in desizing recipe?

Sandoclean DTC is used as wetting agent and NaCl acts as process activator.

ii. Why temperature is maintain between 650c and 700c?

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We maintain temperature in the range of 650c to 700c because above this temperature enzymes are killed and are deactivated.

Before Desizing:

After Desizing:

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Practical No. 2

SCOURING OF FABRIC

Scouring:

Scouring is a process which is carried out to removeall the impurities present in a fabric, such as oils,fats, waxes and other impurities which may hurdle inthe absorption of dyes.

Objectives:

o To remove the impurities from the fabric.o To have a uniform absorbency throughout the fabric

structure.o To make it ready for subsequent process (bleaching,

dyeing or printing) without any hurdle.

Apparatus:

vii. Match Boxviii. Stove

ix. Thermometerx. Weighing Balance

xi. Measuring Flaskxii. Vessel

Chemicals:

i. Sandoclean BC(wetting agent) 0.5g/L ii. Sirux (squesting agent) 2g/L

iii. NaOH 2g/L

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Conditions:

iv. Liquor ratio = 1:30v. Temperature = 100 0c

vi. Time = 30-40 min

Procedure:

o First off all we took the desized fabric and thenweighed it.

o Then according to liquor ratio we took the waterand other chemicals.

o Then we dipped the fabric in the solution of waterand other chemicals and then heated the water up to1000c.

o We measured the temperature with the help ofthermometer.

o Tongs were used to remove the cover of the vesselin which fabric was dipped.

o When 1000c was achieved then fabric was dipped inwater for half an hour at this temperature.

o After half an hour fabric was given hot wash twicefor half an hour.

o Then we gave it a cold wash and then the fabric wasdried.

Calculations:

Fabric weight = 600g

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Liquor ratio = 1:30

Water used = 600 x 30

=18000g

=18000/1000

=18 liter

Amount of the sandoclean = gramperliterxamountof water1000

= 0.5g

Lx18000mL

1000

= 9 grams

Amount of the NaCl = gramperliterxamountof water1000

= 2gLx18000mL

1000

= 36 grams

Amount of the sirus = gramperliterxamountofwater1000

= 2gLx18000mL

1000

10

= 36 grams

Precautions:

o Glassware apparatus and open saturator should be washed properly.

o Use lab coats in lab to avoid from action of chemicals on clothes.

o Use gloves to avoid from action of chemicals on hands.

o Harmful chemicals should be treated carefully otherwise they can damage the skin.

o Chemicals should be weighed accurately otherwise goodresult will not be obtained.

Review Questions:

i. Why scouring process is essential for dyeing cottonfabric?

Waxes which are present on the surface of fabric are removed in this process and we cannot get even shade without scouring so this process is essential for dyeing cotton fabric.

ii. WhySirrex2UD is used in scouring recipe?

It swells up the fabric so that trash can be removed easily.

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Before Scouring:

After Scouring:

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Practical NO. 3

BLEACHING of FABRIC

Objective:

The main objective of Bleaching is

o To achieve maximum whiteness.o To remove natural color impuritieso To have a uniform absorbency throughout the

fabric structureo To produce even fabric surface for dyeing and

printingo To make it ready for subsequent process

(bleaching, dyeing or printing) without anyresistance or hurdle.

Apparatus:

The apparatus used in the experiment was

i. Measuring Cylindersii. Measuring Balance

iii. Thermometeriv. Tubv. Stove

vi. Fuel Source

Chemicals:

The chemicals used for Bleaching are13

i. H2O2(Bleaching agent) 9g/L ii. SandoClean 4g/L

iii. Sirrix (squesting agent) 2g/Liv. NaOH 6g/Lv. Stabilizer 1g/L

Conditions:

i. Temperature = 100 0Cii. Time =30 min

iii. Liquor Ratio =1:30iv. Hot wash and cold wash

Procedure:

o First off all we took the Scoured fabric and thenweighed it. As we did in lab it weighed 600 g.

o Then according to liquor ratio we took the waterand other Chemicals.

o Then we added the chemicals in the water at roomtemperature and then heated it to 400C.

o At this temperature, we dipped the fabric in thewater and then raised the temperature to about 700C.

o At 700C we added H2O2 and then we heated it to about900C for 30 min.

o Then we gave it hot wash twice and the temperatureof water was kept 60-700C

o Then a cold wash was given once.

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Calculations:

Fabric weight = 600g

Liquor ratio = 1:30

Water used = 600 x 30

=18000g

=18000/1000

=18 liter

Amount of the sandoclean = gramperliterxamountofwater1000

= 4gLx18000mL

1000

= 72 grams

Amount of the Sirrix = gramperliterxamountof water1000

= 2gLx18000mL

1000

= 36 grams

Amount of the NaOH = gramperliterxamountofwater1000

= 6gLx18000mL

100015

= 108 grams

Amount of the stablizer = gramperliterxamountof water1000

= 1gLx18000mL

1000

= 18 grams

Amount of the H2O2 = gramperliterxamountofwater1000

= 9gLx18000mL

1000

= 162 grams

Precautions:

o Weight the fabric carefully.o Use tongs to remove the cover of steel tank.o Check the temperature carefully.

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Before Bleaching:

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After Bleaching:

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Practical No. 4

REACTIVE DYEING

Objective:

o To make the fabric coloredApparatus:

i. Glass Beakersii. Measuring Cylinder

iii. Pipettesiv. Stirrerv. Stove

vi. HTC dyeing Machinevii. Dyeing vessel

Chemicals:

The chemical used for dyeing process are

i. Reactive Redii. Shade 2 %

iii. Sodium Chloride ( NaCl ) 25 g/L iv. Sodium Carbonate (Na2CO3) 3 g/L

Conditions:

i. Liquor ratio 1:30ii. Temperature 80 0C

iii. Time 30-45 miniv. Hot wash at 70 0C

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v. Cold wash

Calculations:

Fabric weight =3g

Liquor ratio = 1:30

Water used = 3 x 30

=90mL

Color:

Shade of color = 1%

Amount of color solution to be pippeted out =weightoffabricxpercentageofshade

concentrstionofdyesolution

= 3gx11

= 3 mL

Water:

Amount of the water = Total amount of liquor – Amount of color solution

= 90 – 3

=87 mL20

NaCl:

Amount of the NaCl = 25 g per 1000 mL

1 mL contains NaCl = 251000

90 mL contains NaCl = 25×901000

= 2.25 grams

Na2CO3

Amount of Na2CO3 = 3g per 1000 mL

1 mL contains Na2CO3 = 31000

80.2 mL contains Na2CO3 = 3×901000

= 0.27 grams

Procedure:

o First off all we took the bleached fabric and thenweighed it. As we did in lab it weighed 4.01 g.

o We calculated the amounts of dye and otherchemicals.

o We prepared 1 % solution of Reactive Green.o We weighed the calculated amount of other

chemicals.

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o We took special vessel of HT Dye Machine, with thehelp of beakers we added water according to L:R, inthis vessel. We pippeted out calculated amount ofdye solution to this vessel.

o We added all other chemicals in the vessel.o After stirring, fabric sample was added in the dye

bath.o This vessel was put into the machine and the

program was adjusted on the machine.o On completion of required time, machine was stopped

and the fabric was put to hot wash at 70 0C.o Then we gave it a cold wash and then the fabric was

dried.

Precautions:o Weight the fabric carefully.o Check the temperature carefully.o Use chemicals with great care.

Before Dyeing:

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After Dyeing:

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