Views: 4 Author: Site Editor Publish Time: 2023-05-05 Origin: Site
Cooking is to remove natural impurities on cotton fabrics with chemical methods and physical methods to achieve the purpose of refining and purifying cellulose. Cooking is a very important link in the previous processing process. It especially emphasizes the repetitiveness of the process and the consistency of product quality.
With high mature cotton fiber, its cellulose content reaches more than 94%, and the impurities that need to be removed during refinement are about 6%.
The closer to the outer layer, the higher the impurities. These impurities are mainly located on the surface of the newborn wall. The hydrophobic layer with pectin as the skeleton is formed through the main chain of the pectin and the branches. The main purpose of refining is to destroy and remove this hydrophobic mesh layer, especially to remove wax.
Natural fiber has a pigment with a pigment -like pigment with a pigment -like dye in the growth process. This pigment cannot be completely removed during the cooking process, and can only be removed by bleaching process.
The purpose of bleaching is to remove natural pigments and improve the whiteness of fabrics. At the same time, other impurities remaining on cotton fabrics, such as cottonseed shells, wax, nitrogen -containing substances, etc. Essence
The oxidant and reducing agent can bleach natural fibers, but the pigment does not completely destroy the pigment in natural cellulose. One is the limited whiteness after the restoration of the bleach. Therefore, the bleaching effect is ideal; the oxidant can destroy the pigmented molecules in natural fibers, and its bleaching is persistent.
Commonly used reducing bleaching agents include: sodium sulfate, sodium sulfate, insurance powder, etc. The commonly used oxidative bleach is: hypochliparite, sodium sodium chloride, hydrogen perpasposol, potassium permanganate, etc.
At present, the main method of domestic bleaching of cellulose fiber is hydrogen peroxide bleaching method. The hypochlorite bleaching method is only used in hemp fabrics, while other bleaching methods are basically replaced by the above methods for various reasons. In the production process, there is only dialogue in the production process. Other bleaching methods with special requirements with special requirements will be used.