Effect of bleaching on the dyeing property of purple cashmere

In order to improve the dyeing quality of the bleached purple cashmere,the effect of bleaching technology on the dyeing property of purple cashmere is discussed in this paper.The influence of color and luster of the original cashmere,whiteness value,auxiliary agent SLS and Fe~(2+) removal treatment on the dye uptake rate is investigated separately.The results show that the balance dyeing rate of the bleached purple cashmere decreases with increase of the fiber whiteness;bleaching has impact on weak acid,reactive and mordant dyes,and without exception to these dyes,the dye uptake of the bleached purple cashmere decreases.Especially to mordant dye,the residue of Fe~(2+) will react with dye,vying with Cr~(3+) in dyeing process.Compared with original cashmere,bleached purple cashmere is more sensitive to dyeing conditions,which makes the dyeing evenness decreased.The use of dye in the low temperature is optimization process.