Cotton knitwear low-temperature bleaching pre-treatment method

Abstract

The invention discloses a cotton knitwear low-temperature bleaching pre-treatment method. The method comprises cotton knitwear low-temperature bleaching, water washing, acid neutralization and deoxygenization. Cotton knitwear is formed through blending of cotton fibers, cellulose acetate fibers and / or chitosan fibers, the content of the cellulose acetate fibers and / or chitosan fibers is above 20%,the low-temperature bleaching temperature is 70 to 80 DEG C, the time is 30 to 60 min, a treatment solution comprises 0.5 to 2 g / L of emulsifying agent, 0.5 to 1 g / L of penetration agent, 4 to 10 g / Lof caustic soda, 6 to 12 g / L of hydrogen peroxide and the balance water. It is unexpectedly found that acyl contained in special fibers such as the cellulose acetate fibers and the chitosan fibers can catalyze activated hydrogen peroxide to bleach cotton knitwear, it is ensured that the good bleaching effect is obtained at the low bleaching temperature, low-temperature bleaching is achieved without adding of activator / catalyst, the method is more friendly to the environment, and finally, energy saving and environment friendliness are achieved at the same time.

Description

technical field [0001] The invention belongs to the technical field of pretreatment of textile printing and dyeing, and in particular relates to a pretreatment method for low-temperature bleaching of cotton-containing knitted fabrics. Background technique [0002] Cotton is a natural cellulose fiber, its main component is cellulose, but there will be impurities such as pectin, waxy substances, ash, natural pigments and other impurities during the growth process, the existence of these impurities will seriously affect the uptake of dyes during the dyeing process. Therefore, it needs to be removed through pre-treatment processes such as scouring and bleaching before dyeing. [0003] Among them, the traditional method for pre-bleaching of cotton fibers is hydrogen peroxide bleaching, but conventional hydrogen peroxide bleaching needs to be carried out at high temperature (above 95°C) for a long time (about 1h) to achieve the best bleaching effect, which not only consumes more e...

AI Technical Summary

Problems solved by technology

However, since the activator / catalyst does not participate in the final reaction, but is discharged with the wastewater, it not only increases the difficulty of sewage treatment, but is also unfriendly to the environment

[0007] Therefore, the existing low-temperature activation / catalytic bleaching only solves the problem of "energy saving", but cannot solve the problem of "environmental protection"