jvbdjkhsdkv

1. Classification and general properties of colorants
 Solutions
 Percentage
 Mole fraction
 Molality
 Molarity
In this lecture We ''ll learn about
Lecture 1

2. • Theory
• Reactive dye:
• A class of colored synthetic organic chemicals that attach to textile fibers via a
chemical reaction that forms a covalent bond. Reactive dyes are the most
permanent of all dye types and are the most common type of dye used on cotton
and other cellulose fibers.
• . Exhaust Process:
• Batch Process is the most popular and common method used for processing of
textile materials. Batch process is also sometimes referred to as Exhaust Process.
•
• Equipment & Material:
• Cotton fabric, wetting agent, weighing balance, pH meter, water bath, measuring
cylinder, reactive dyes, soda ash, caustic soda, salt
Title: Dyeing of 100% cotton fabric using reactive dyes in exhaust method and
study the effect of salt on shade depth.

3. • Working Procedure:
• Weigh all the chemicals and dyestuff according to the calculation w.r.t L:R.
• Start dyeing at room temperature by putting fabric in the liquor
• Wait for 15 minutes and add half the amount of salt calculated.
• Let the temperature raise up to boiling or prescribed temperature.
• When the temperature reached on desired level, add rest of salt and soda ash for
pH.
• Let the dyeing be carried out for 45 min. After that cool down the dye bath.
• Rinse, wash & rinse the fabric
• Dry the fabric using oven
• Check the fastness properties
H

4. • Observations& Calculations:
• Subjective Evaluation
• Take Liquor Ratio 1/50
Reactive
dyes
Dyes
Wetting
Agent
Sequesteri
ng agent
Salt PH Temprature Time Shade
depth
Fastness
properties
1 % 1 g/l 1 g/l 10 g/l 11
soda
ash
60 C 45
minute
s
3 % 1 g/l 1 g/l 20 g/l 11
Soda
Ash
65 C 45
minute
s
6 % 1 g/l 1 g/l 30 g/l 11
Causti
c
70 C 45min
utes

5. • Graphs and Charts:
• Demonstrate results in charts and graphs using data. Always add Standard
deviation (SD).
• Conclusions: to the process, chemicals, working conditions, and results (as
presented in graphs and charts).
H

6. • Questions:
• What is Reactive dyes?
• What is the effect by increasing the dyes percentage?
• What is exhaust process?
• What is the effect by increasing salts concentration?
•
H

7. The
H

8. The
H

9. The
H

10. The
H

11. The
H

12. The
H

13. The
H

14. The
H

15. The
H

16. The
H

17. The
H

18. The
H

19. The
H

20. The
H

21. The
H

22. The
H

23. The
H

24. The
H

25. The
H

26. The
H

27. The
H

28. The
H

29. •
•
• Theory
• What is meant by direct dyes?
• Direct dye, also called Substantive Dye, any of a class of coloured, water-soluble
compounds that have an affinity for fibre and are taken up directly, such as the
benzidine derivatives. Direct dyes are usually cheap and easily applied, and they
can yield bright colours.
Experminet # 1
To dye 100% cotton fabric with direct dyes using exhaust method.
1,2-diphenylhydrazine 1,1'-biphenyl-4,4'-diamine

30. • Exhaust Process:
• Batch Process is the most popular and common method used for processing of
textile materials. Batch process is also sometimes referred to as Exhaust Process.
• Equipment & Material:
• 100% cotton fabric, wetting agent, weighing balance, pH meter, water bath,
measuring cylinder, direct dyes,Salt.
•
H

31. • Weigh all the chemicals and dyestuff according to the calculation w.r.t L:R.
• Start dyeing at room temperature by putting fabric in the liquor.
• Wait for 15 minutes and add half the amount of salt calculated.
• Let the temperature raise up to boiling or prescribed temperature.
• When the temperature reached on desired level, add rest of salt and soda ash for
pH.
• Let the dyeing be carried out for 45 min. After that cool down the dye bath.
• Rinse, wash & amp; rinse the fabric.
• Dry the fabric using oven.
• Check the fastness properties.
Working Procedure:

32. Observations& Calculations:
Subjective Evaluation
Take Liquor Ratio 1/50
H
Direct Dyes Wetting
Agent
Sequestering
agent
Salt PH Tempratu
re
Time Shade
depth
Fastness
properties
1 % 1 g/l 1 g/l 10 g/l 8 - 9 80- 90 C 45 minutes
3 % 1 g/l 1 g/l 20 g/l 8 - 9 80- 90 C 45 minutes
6 % 1 g/l 1 g/l 30 g/l 8 - 9 80- 90 C 45minutes

33. • What is direct dyes?
• What is the effect by increasing the dyes percentage?
• What is exhaust process?
• What is the effect by increasing salts concentration?
Questions:

34. The
H