Dyeing process for spun silk

Abstract

The invention provides a process for dyeing spun silks, belonging to the weaving yarn dyeing technical field. The process comprises the following steps that: spun silk yarns which are ready to be dyed and undergo the pre-dyeing treatment are put in a dye vat, water is added in the dye vat, and the bath ratio is controlled; at the normal temperature, auxiliary agent and cotton-used reactive dyes are added in the dye vat; the dye vat is kept warmth at the normal temperature; at the normal temperature, salt is added in the dye vat; the dye vat is kept warmth at the normal temperature again; the dye vat is heated, and the temperature-rise speed is controlled; the dye vat is kept warmth; finally after sequential steps of temperature drop and liquid discharging, fresh water washing, soap washing, hot water washing, color fixation, upper flexibility, dewatering and drying, dyed spun silk yarns are obtained. The process has the advantages of improving the color fastness of dyed spun silk yarns by one or two levels, having good level-dyeing property, improving the color yield by 20 percent and improving the breaking strength by 5 to 10 percent; because alkali is not used for the color fixation, the process has the advantages of simple process, unnecessary following acid neutralization step, energy conservation and low dyeing cost; because alkalization and acid neutralization steps are not necessary, the process is environment friendly.

Description

technical field [0001] The invention belongs to the technical field of dyeing of textile yarns, and in particular relates to a dyeing process of spun silk. Background technique [0002] Spun silk (spun silk), also known as spun yarn, belongs to the category of yarn. It is processed from recycled silk or waste silk) and belongs to protein fiber. Spun silk is a high-grade silk weaving material, and the silk fabrics made of it are very popular among people. [0003] At present, the dyeing of spun silk in the industry mainly adopts the traditional process of dyeing cotton with reactive dyes under alkaline conditions, which can be specifically determined by figure 1 As shown, add auxiliaries and reactive dyes for cotton to the dyeing container such as a dyeing vat at room temperature, and keep warm; then add salt, keep warm; then fix the color, and heat up from room temperature to 60-80°C at a heating rate of 1°C / min After 5-10 minutes of heat preservation, add alkali (soda as...

AI Technical Summary

Problems solved by technology

The disadvantage of this kind of dyeing process is: due to the existence of the alkali-adding process, the workers are cumbersome to operate. If the operation is improper, such as adding alkali too quickly or unevenly, it will cause serious color flowers, and under alkaline conditions, it will damage the dyeing process. And silk fibroin, resulting in a decrease in the strength of silk, and under the condition of adding alkali, due to the intensification of hydrolysis of reactive dyes, the percentage of dyeing will further decrease, and the subsequent processes such as washing process are strictly required. If it is not washed, there will be alkali residual, then there will be weathering phenomenon after drying in the last drying process, which will affect the color reproducibility of silk; since the temperature used in the color fixing process is 60-80 °C, this temperature is not conducive to speeding up the dyeing speed and increase the dye uptake rate, because the selection of this temperature value does not treat cotton fiber and spun silk differently, so it is blind to a certain extent

And because spun silk belongs to protein fiber, the swelling degree of protein fiber in water increases as the temperature rises, and the voids in spun silk fibers increase accordingly, which is conducive to the entry of reactive dye molecules into the fiber and diffusion inside the fiber , so as to speed up the dyeing speed and increase the dyeing rate. Although affected by the characteristics of the dye itself, the temperature cannot be increased without restraint, but it is at least not an ideal temperature for the color fixing temperature of 60-80 ° C; due to the presence of alkali addition process , so the subsequent acid neutralization process is required, which not only leads to cumbersome process, waste of energy, and increased cost, but also produces unfavorable factors for environmental protection

[0004] In fact, although people have objectively realized the many unfavorable factors caused by the aforementioned spun silk dyeing process, but due to the constraints and deep-rooted influence of the traditional concept of craftsmanship, they dare not go beyond the threshold, thus hindering and inhibiting exploration and innovation.

Images