What are the pretreatment agents for printing and dyeing

The pre-treatment process of printing and dyeing includes fiber singeing, desizing, scouring, bleaching, mercerizing and other processing processes. Penetrating agents, emulsifiers, cleaning agents and other surfactants need to be added to organic sulfates, sulfonates and polyoxyethylene. ether-based.

1. Penetrating agent, wetting agent

The commonly used penetrants in the textile industry are the sulfate of butyl ricinoleate, the sodium salt of butylnaphthalene sulfonate, and the like. In neutral solution, sodium dioctyl succinate sulfonate has particularly strong penetration ability; in acidic solution, in addition to the above varieties, fatty alcohol polyoxyethylene ether or alkylphenol polyoxyethylene ether is commonly used; In solution, such as mercerization process, a shorter carbon chain sulfate such as octanol sulfate is used.

2. Emulsifier

In the textile process, oiling is often necessary to improve the lubricating properties of silk and yarn. However, oil should be removed before printing and dyeing to avoid affecting the dyeing. Therefore, emulsifiers should be added to these textile oils beforehand, or emulsifiers should be added to the cleaning bath to ensure the removal of oil spots. Generally, non-ionic surfactants are used.

3. Cleaning agents, namely detergents, detergents

Removal of oil from textiles, which used to be based on soap, now uses a variety of synthetic detergents and non-ionic surfactants, including slightly more expensive oleic acid amide derivatives.

In addition, there are enzymes used to promote starch hydrolysis during desizing; activators and anti-corrosion agents are added during bleaching to speed up the bleaching process and increase the brightness without corroding equipment. At present, the desizing, scouring, and bleaching have been completed in one bath, and a new compound strong cleaning aid is used.