What chemicals are used in denim washing?（2）

Sixth. Surfactant

Surfactant is a substance with fixed hydrophilic and oil-philic base group, which can be arranged directionally on the surface of solution and can significantly reduce the surface tension of solution. Surfactant has a wide range of applications in industrial production and daily life, its important roles are wetting, solubilizing, emulsifying, foaming, defoaming, dispersing, decontamination and so on.

1, wetting agent: non-ionic wetting agent is particularly unsuitable for enzyme and other sensitive substances in the bath, in the desizing process can increase the penetration of enzyme molecules on the fabric, improve the effect; Adding non - ionic wetting agent in the process of soft finishing can significantly improve the soft effect.

2. Anti-dyeing agent: The anti-dyeing agent consists of polyacrylic acid polymer compounds and non-ionic surfactants, which can prevent indigo dyes, direct dyes and reactive dyes from dyeing the clothing labels, cloth, embroidery, decals and other parts in the washing process, as well as prevent the dyeing of printed fabrics and yarn-dyed fabrics in the washing process. Suitable for enzyme washing process of denim clothing. Anti-stain agent not only has strong anti-stain effect, but also has extraordinary desizing and cleaning function, and cellulase in the same bath, can promote the cellulase, greatly improve the degree of denim clothing washing, shorten the washing time, reduce the amount of enzyme 20%-30%. The composition and composition of the anti-dye products produced by various manufacturers are not the same. At present, the products for sale have a variety of dosage forms such as powder and water agent.

3, wash agent (oil) : not only has strong anti-staining effect, but also has extraordinary desizing function and wash function. It can remove floating color and improve permeability when it is used for enzyme washing of leisure clothing. It can obtain clean and bright luster when it is used for enzyme washing. Soap oil is the most common detergent for clothing washes, its properties can be evaluated by testing dispersion, emulsification and decontamination power.

Seventh. Auxiliaries

1. Fixing agent: After dyeing cellulose fibers with direct dyes and reactive dyes, if washed directly, it will cause color shifting of unfixed dyes. In order to prevent the occurrence of this phenomenon and achieve the desired color fastness, usually textiles need to be fixed after dyeing. Color fixing agent is an important compound to improve the binding fastness of dyes and textiles. The existing color fixing agent is divided into: dicyandiamide color fixing agent, polymer quaternary ammonium salt color fixing agent.

2. Bleaching agent

① Spandex chlorine bleaching agent: chlorine bleaching agent and sodium hypochlorite used in the same bath can prevent the damage caused by bleaching of elastic silk and fabric after washing yellowing.

② Hydrogen peroxide bleaching stabilizer: hydrogen peroxide bleaching under alkaline conditions at the same time, but also make cellulose oxidation damage, resulting in fiber strength decline. Therefore, the effective decomposition of hydrogen peroxide must be controlled during hydrogen peroxide bleaching, and the stabilizer is generally added in the bleaching solution.

③ Hydrogen peroxide bleaching synergist: used together with caustic soda and hydrogen peroxide has special effect on the bleaching decolorization of vulcanized black dyed denim clothing.

④ Manganese removal agent (neutralizer) : after potassium permanganate treatment of denim fabric surface residual manganese dioxide, must be clear and clean, in order to make the bleached fabric show bright color and appearance, this process is also known as neutralization. The important ingredient is reducing agent.

3. Resin finishing agent

The role of resin finishing: cellulose fiber fabric, including cotton, hemp, viscose fabric, comfortable to wear, good moisture absorption, but easy to deform, shrink, wrinkle, crisp poor. This is because under the action of water and external force, there is relative slip between the amorphous macromolecular chains in the fiber. When the sliding macromolecular chains are removed by water or external force, there is relative slip between the sliding macromolecular chains, and when the sliding macromolecules cannot return to the original position after the removal of water or external force, resulting in folds. After resin treatment, clothing crisp, not easy to wrinkle deformation, can be ironing free. In addition to wrinkle prevention, the crepe grabbing and crepe pressing process in denim washing also requires resin shaping, which can keep the wrinkling effect unchanged for a long time. Resin finishing technology in clothing washing should have the characteristics of fixed pleating and color fixation.

Commonly used resin finishing agent: ① cat hair crepe resin. ② resin finishing catalyst. ③ Fiber protective agent. Additives to improve the strength of fabric.

Eighth, antistatic agent

Electrostatic harm: clothing and human body adsorption; Fabric attracts dust easily; There is a tingling feeling in the underwear; Synthetic fabrics produce an electric shock.

Antistatic agent products: antistatic agent P, antistatic agent PK, antistatic agent TM, antistatic agent SN.

Ninth, softener

1, the role of softener

When the softener is applied to the fiber and absorbed, it can improve the luster of the fiber surface. Applied to the surface of the textile to improve softness. The softener acts as a lubricant and is adsorbed on the surface of the fibers, thus reducing interactions between the fibers and improving their smoothness as well as their mobility. The softener has the following characteristics: ① The performance remains stable during processing. ② Can not reduce the whiteness and color fixation of clothing. ③ It can not be yellow and discolored when heated. ④ After storage for a period of time, it can not cause the change of color and feel of goods.

2, softener products: cold water drinking tablets, hot melt non-ionic film, fluffy softener, bright softener, moisturizing soft oil, anti-yellowing silicone oil, anti-yellowing softener, penetration silicone oil, smooth silicone oil, hydrophilic silicone oil.

Tenth, fluorescent whitening agent

Fluorescent brightening agent is a preparation of increasing the whiteness of fabrics under the sun by the use of optical effect, so it is also called optical brightening agent, which is close to colorless dyes. The fluorescent brightening agent used for clothing washing and whitening is mainly cotton brightening agent, which is divided into blue light brightening agent and red light brightening agent.

Elventh. Other chemical agents

Abrasive: Used for light fabric grinding treatment, can replace pumice stone, in order to avoid damage to the cloth surface and stone marks, scratches.

Stone grinding powder: pumice stone is the best substitute, the effect is better than grinding agent.

Sand wash powder: The surface produces fluff effect.

Stiffening agent: strengthen the feeling of thickness.

Fuzz agent: enhance the fuzz feel of clothing, soluble with enzyme preparation.

Paint: In accordance with the weight and effect requirements of clothing during operation, with different proportions of paint mixed with water, plus 10% solid color paste, in the clothing need to spray or drop or pen to create irregular patterns.