Effective measures to improve colour fastness to wet friction（1）

Among textile products, the main factors affecting the color fastness to wet rubbing are fabric type and fabric structure;  Textile pretreatment, such as desizing, cooking, bleaching, mercerization, etc.  The selection of textile dyes, as well as the process, temperature, time control is strict, and the selection and use of additives is correct;  Textile after treatment, etc.  

In view of these factors affecting the color fastness to wet rubbing, we should pay attention to the following points:  

1.According to the analysis of textile material science, the general chemical fiber fabric has better color fastness to wet friction than cotton and other natural fabrics, and the thin fabric is better than the heavy fabric.  Therefore, in textile processing, each process should be evenly treated to improve the absorbability of fiber and the reactivity or adsorption fixation of dye, so that the dye is fully dyed.  In the dyeing process, strict control is required, and auxiliaries must be correctly selected and used.  In order to improve the color fastness to wet rubbing of textile products, full soaps can be carried out in the post-treatment of textiles. For example, polyester fibers dyed with disperse dyes are set at high temperature, resulting in dye swimming to the fiber surface, resulting in a decrease in rubbing fastness.  In this case, fixing agent or smoothing agent can improve the color fastness to friction to a certain extent.  

2.When selecting dyes, choose dyes with good lifting and levelling, which are conducive to the penetration and diffusion of dyes, and can improve wet rubbing fastness to a certain extent.  The dye should have a certain water-soluble and direct, water-soluble group can not be too much, otherwise it will affect the wet rubbing fastness behind.  And the directness should also choose medium as the best.  The selected dye should not have too high directness, generally should be greater than 70%.  

3.The color fastness to wet rubbing of natural fabrics such as cotton is relatively poor, so the grey cotton fabric with uniform yarn count and smooth surface should be selected.  High-efficiency pre-treatment agent should be used if pretreatment is needed.  

4.Reactive dyes should use soft water or deionized water as far as possible to reduce the influence of calcium and magnesium plasma in the water on the dye, so as to improve the absorption of dye fiber, dye in the fiber molecule fixation more stable.