Improved cashmere oxidation-reduction bleaching method

Abstract

The invention discloses an improved cashmere oxidation-reduction bleaching method, which includes the following steps: (a) pre-treating cashmere with 1-3 wt% of a chelating dispersion agent, 0.5-2 wt% of a surfactant, 2-5 wt% of a penetrating agent, 0.1-0.4 wt% of p-tolyl phenylacetate and 0.5-1 wt% of 2,4,5-trimethyl benzaldehyde; (b) performing oxidation bleaching with 40-47 wt% of hydrogen peroxide, 12-15 wt% of sodium pyrophosphate, 0.75-1.2 wt% of sodium pyridine-3-carboxylate, 1.3-1.5 wt% of potassium methyl malonate, 0.05-0.12 wt% of 2,4-dimethyl phenol and 3.5-5 wt% of 5-sulfosalicylic acid; (c) performing neutralizing washing with 35-45 wt% of isopropyl alcohol, and 3.6-7 wt% of s-butyl-diethyl malonate; (d) performing reduction bleaching with 7-10 wt% of sodium hydrosulfite, 3.5-4 wt% of sodium pyrophosphate, 5-7 wt% of acetic acid, 5-6% of softening agent, 0.65-1 wt% of hydroxyethyl acrylate, and 1.1-1.5 wt% of 2-bromo-2'-fluoroacetophenone, and (e) washing the cashmere with deionized water. The method can reduce damage on scale layer on the cashmere during the bleaching process.

Description

technical field [0001] The invention relates to the technical field of dyeing and finishing, in particular to an improved redox bleaching method for cashmere. Background technique [0002] Cashmere is a high-grade textile raw material, which has the effects of light weight, softness and warmth. However, cashmere has poor alkali resistance and heat resistance. Therefore, when it is necessary to meet a certain whiteness requirement and protect the strength of wool, the choice of bleaching method and process is particularly important. Chinese invention patent CN102851936B discloses a low-damage bleaching method for wool fabrics, which reduces the strength damage of wool fabrics. But, find in inventor's recent research, although this bleaching method can reduce the damage of woolen fabric, can cause irreversible change to the scale layer of wool (specifically, the bonding degree of scale layer and cortex layer descends, causes scale layer layers tend to come off, reducing the ...

AI Technical Summary

Problems solved by technology

However, the scale layer of cashmere is much thinner than that of wool. If the same bleaching method is applied to cashmere, it will have a significant impact on the service life of cashmere fabrics.