Page 93 - Shawl Weaving Artisan - TP

Textile & Handloom Exercise 1.6.55
Shawl Weaving Artisan - Wet Processing

Dyeing of fiber, yarn and fabric with direct dyes

Objectives : At the end of this exercise you shall be able to
• dyeing the wool fiber, yarn and fabrics with direct dyes
• dyeing the cotton fiber, yarn and fabrics with direct dyes.

Requirements

Tools/equipment’s/Instruments
• Gas stove - 1 No. • Measuring cylinders - 1 No.
• Stainless steel beaker - 1 No. • Glass /metal stirring rods - 1 No.
• Direct dyes( of different shades) - as reqd. • Rubber Gloves.(disposable) - 1 Set.
• Acetic acid - as reqd. Materials
• Soda ash - as reqd. • Wool, cotton yarn hanks - as reqd.
• Common salt - as reqd. • Wool and cotton fabric - as reqd.
• Lab thermometer - 1 No.
PROCEDURE

TASK 1: Dyeing of wool yarn with direct dyes
Preparation Cooling and rinsing
1 Take wool yarn hank and weight it to determine the 9 Gradually cool the dye bath to around 40°C to 50°C.
amount of dye and chemicals required.
10 Rinse the wool yarn thoroughly with cold water to
2 Then wash the wool yarn in cold water to remove remove any excess dye.
any impurities.
Neutralization
Dyeing 11 Mix acetic acid with water (around 1% to 2% of the

3 Make a paste of dye by add it with water and mix weight of the wool).
the dye with hot water (around 40°C to 50°C) in the 12 Immerse the wool yarn in the neutralizing solution.
dyeing vessel.
13 Let it treat for 10-15 minutes.
4 Then add salt (sodium chloride) to the dye bath
(around 10% to 20% of the weight of the wool). Rinsing and drying
5 Then add soda ash (sodium carbonate) to the dye 14 Rinse the wool yarn thoroughly with cold water to
bath (around 2% to 5% of the weight of the wool). remove any remaining neutralizing solution.
6 Then immerse the wool yarn in the dye bath. 15 Gently squeeze out excess water from the wool
yarn.
7 Heat the dye bath to (around 80°C to 90°C).
16 Then dry the wool yarn in a room temperature.
8 Maintain the temperature and let the wool yarn dye
for 60-90 minutes.

TASK 2: Dyeing of wool fabric with direct dyes
For wool fabric dyeing, follow the steps 1 to 16 mentioned
in TASK 1.

TASK 3: Dyeing of cotton yarn with direct dyes

1 Take a cotton yarn hank and weight it to determine 4 Then add salt (sodium chloride) to the dye bath
the amount of dye and chemicals required. (around 05% to 10% of the weight of the cotton
yarn).
2 Then wash the cotton yarn hank in a cold water to
remove any impurities. 5 Then add soda ash (sodium carbonate) to the dye
bath (around 2% to 5% of the weight of the cotton
3 Make a paste of dye by add it with water and mix yarn).
the dye with hot water (around 40°C to 50°C) in the
dyeing vessel. 6 Then immerse the cotton yarn in the dye bath.
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