Cotton dyeing by reactive dye semi-continuous method:
Pad roll method:
Recipe:
Dyestuff → 3% (on product weight)
Soda ash → 15 g / liter
Salt → 60 g / liter
Temperature → 20°C to 250C
Urea → 150 g / liter
Sodium alginate → A small amount
Dyeing Process:
The wet cloth is first padded in a bath containing dyestuff, alkali, urea, and wetting agent. At this time the temperature is kept from 20°C to 25°C. The padded cloth is taken to a chamber in the form of a roll. Four such rolls are made together and kept in the chamber at a temperature of 20°C and 100% humidity. While in the chamber, the rolls are rotated slowly. The batching time may vary from 2 to 4 hours, depending on the dye’s reactivity. The cloth is then washed in cold water and treated with a soap solution. Finally washed with cold water and taken for further activities. This method is suitable for high reactivity dye. https://bdfabric.com/oxidizing-and-reducing-bleaching-agent-in-textile/
Cotton dyeing by reactive dye semi continuous method-Pad jigger method:
Recipe:
Dyestuff → 3% (on product weight)
Salt → 60 g / liter
Soda ash → 15 g / liter
Water →15 times
Temperature → 40°C to 90°C
Time → 1 hour 30 minutes.
Dyeing process:
First, the stock solution is made by measuring the quantity of dyestuff. The squared/bleached cloth is then taken in a water bath. Then the dye solution is slowly added. After 10 minutes of dyeing, add salt slowly and shake with the cloth. Soda ash is added 15-30 minutes after adding salt. Then gradually increase the temperature from 40°C to 90°C and dye for 1 to 1.5 hours. It is then washed thoroughly with cold water and treated with the soap solution and then re-washed.
Mention that light acid washing at the end of the dyeing process increases the brightness of the shade.
