What are the commonly used desizing methods and their effects?

(1) Hot water wash

In order to save costs, many manufacturers use hot water desizing. Hot water can only dissolve some water-soluble pulp, can not degrade the pulp, the viscosity of the pulp can not be reduced, the desizing rate is low, and the pulp dissolved in the hot water will re-stick to the clothing, so the application of this method very limited.

(2) Alkali desizing

The ability of caustic soda to remove starch is strong, and at the same time, it has a certain decontamination ability. Due to the action of alkali and cotton cloth, it is difficult to remove the residual alkali on the cloth surface, and it is necessary to increase the number of cleanings. If the cleaning is not clean, it will affect the subsequent color registration and enzyme washing process. If the clothing fabric contains polyester, the alkali will also cause damage to the polyester fiber.

(3) Softener desizing

Softeners are generally aliphatic cationic compounds or macromolecular silicone oils, which have no cleaning ability and no desizing effect. Some manufacturers use softener to desizing, in fact, the main function is to increase the lubrication of the clothing surface and prevent the appearance of washing marks. However, due to the cationic and water-repellent properties of the softener, it is easy to cause problems such as difficulty in enzymatic washing, staining, and uneven horses.

(4) Desizing with detergent

Some manufacturers use washing powder for desizing. The washing powder has a good cleaning effect and has a certain ability to remove the pulp. However, when it is used for denim desizing, the staining phenomenon is serious. Large influence, easy to inactivate enzymes. Non-ionic sap oil has good wetting, emulsifying and cleaning functions, as well as anti-staining ability and smoothing effect. It is used by many manufacturers, but the desizing effect is average.

(5) Desizing enzyme desizing

Desizing enzyme is a complex with α-amylase as the main component. Generally, mesothermal amylase is used in washing plants. The effect of single amylase is not good. Desizing effect of the pulp. Compared with other desizing methods, desizing enzyme can clean starch-containing slurry without damaging the fiber, has strong color retention ability, fluffy and soft hand feeling, and is especially suitable for color retention and washing.

(6) Desizing of stone powder

The stone grinding powder is composed of ultra-fine abrasives and a variety of organic components. It can be used for desizing of heavy denim. It can not only remove the slurry, but also abrad the surface of the fabric. In the desizing stage, a part of the stone grinding effect is produced. , which can greatly reduce the amount of enzymes in the subsequent fermentation process, shorten the fermentation time, and is especially suitable for denim desizing with high contrast requirements.

(7) Bleaching and desizing

Bleaching water itself has strong oxidative properties and a certain degree of alkalinity, which can degrade the pulp. At the same time, it has a certain bleaching effect, which can significantly improve the brightness of the cloth surface, but when used alone, the color will fade and the shade will also change. , It is necessary to add chlorine bleach protection agent to not only desizing, but also to ensure that the color does not fade. Using bleaching water and a small amount of caustic soda and chlorine bleaching protective agent together, to desizing denim fabric, the color does not change after desizing, the shade does not change, and the cloth surface does not flower, especially suitable for black cow desizing, which can effectively remove The sulfur smell of black bull.