Notes for Printing and dyeing factory use reactive dye
1. Why do you need to use a small amount of cold water to adjust the slurry when the chemical is used? The temperature of the chemical should not be too high?
(1) The purpose of adjusting the slurry with a small amount of cold water is to make the dye easily and thoroughly wet. If the dye is directly poured into water, the outer layer of the dye forms a gel, and the dye particles are wrapped to make the inside of the dye particles difficult to wet. , so you should first use a small amount of cold water to adjust the pulp, then use hot water to melt.
(2) If the temperature of the chemical is too high, it will cause hydrolysis of the dye and reduce the fixing rate of the dye.
2. Why is it slow and even when feeding?
This is mainly to prevent the dye from being dyed too fast. If the dye is added quickly at a time, the dyeing rate will be too fast, which will make the outer layer of the fiber deep, and the inside is easy to cause color stain or strips.
3. After adding the dye, why should I dye it for a certain period of time (eg: 10min) and start adding salt?
Salt is a dyeing agent. When the dye is dyed to a certain extent, it has reached saturation. It is difficult to continue dyeing and salting to break this balance, but it takes about 10-15 minutes before the salt is promoted. Fully infiltrated evenly, otherwise it will easily cause strips and stain.
4. Why do you want to add salt in several times?
The purpose of the salt addition is to promote the dye evenly, so as not to promote the dyeing too fast, resulting in color stain.
5. Why do you need to fix it after a certain period of time (such as 20 minutes) after adding salt?
There are two main reasons: A, is to let the salt dissolve evenly in the cylinder, fully promote dyeing B, is to let the dyeing into the dyeing saturation to reach equilibrium, and then add alkali fixing color to achieve the highest dyeing amount.