Dyeing of 100% cotton fabric with reactive dye to produce combined shade

Name of the Experiment: Dyeing of 100% cotton fabric with reactive dye to produce combined shade.

Introduction:

Reactive dyes are a class of highly colored organic substances, primarily used for tinting textiles, that attach themselves to their substrates by a chemical reaction that forms a covalent bond between the molecule of dye and that of the fibre. The dyestuff thus becomes a part of the fibre and is much less likely to be removed by washing than are dyestuffs that adhere by adsorption. The most important characteristic of reactive dyes is the formation of covalent bonds with the substrate to be coloured. Fiber reactive dyes are the most permanent of all dye types. Unlike other dyes, it actually forms a covalent bond with the cellulose or protein molecule. Once the bond is formed, what you have is one molecule, as the dye molecule has become an actual part of the cellulose fiber molecule.

 Objective:

1. To learn about dyeing process of cotton fabric by reactive dye.
2. To dye cotton fabric by reactive dye.
3. To make a combined shade using red, yellow, blue color substances.
4. To write a report according to the experiment.

Nature of the sample:

• Pre-treated 100% cotton knitted fabric.

Apparatus Required:

• Beakers.
• Glass Rod.
• Pipette
• Measuring Cylinder.
• Digital Balance.
• Sample dyeing machine.
• Pot.

Process Sequence:

Collection of pre-treated sample

↓ 

 Set water level

↓ 

 Add leveling agent 

↓ 

 Add dye solution

↓ 

 Add salt solution 

↓

Add soda ash solution

↓

 Add fabric sample

↓

Add fabric sample

↓ 

Run time for 30 minute 

↓ 

 Bath drop

↓

Rinsing 

↓

Hot wash at 90deg for 10minute

↓

Drying

 

 Dyeing Recipe has been shown in the table:

Sl No.	Chemicle	Recipe 1	Recipe 2	Recipe 3	Recipe 4
1	Reactive Dye (Red)	3%	1.5%	0.5%	0.8%
2	Reactive Dye (Yellow)	1.5%	3%	0.5%	0.2%
3	Glubar Solt	40 g/l	50 g/l	20 g/l	20 g/l
4	Soda Ash	15 g/l	20 g/l	10 g/l	10 g/l
5	Levelling Agent	1.5 cc/l	1.5 cc/l	1.5 cc/l	1.5 cc/l
6	Wetting Agent	2	2	2	2
7	Sequestering Agent	2	2	2	2
8	Time	30 min - 45 min	30 min - 45 min	30 min - 45 min	30 min - 45 min
9	Temperature	60℃	60℃	60℃	60℃
10	M:L	1:15	1:15	1:15	1:15

 Function of Chemicals:

• Leveling Agent:

  • Control of the exhaustion dye so that it is taken up evenly.
    

•  Sequestering Agent:

   

   

⇝ Sequestering agents or Chelating agents remove metal ions from a solution.
⇝ These agents are used to eliminate water hardness and heavy metals, such as iron and copper which can affect the process.

Reactive Dye:

⇝ Main substances to produce color.

Glauber Salt:

⇝ The salt in the reactive dyeing increases the affinity of the dye towards the Cellulosic substrate.
⇝ Salt increases the exhaustion rate of reactive dyestuffs.
⇝ As reactive dyestuffs have a lower affinity, more inorganic salt is required when using reactive dyestuffs in order to accelerate absorption.

Soda Ash:

⇝ Reactive dyeing required alkali medium, Soda ash control the pH of the dye bath.

Calculation :

Calaulate Your Data

Comments: The fabric absorbed dyes particle very well and turns into violate color.