Reactive dye salt-free dyeing method

Abstract

The invention relates to a reactive dye salt-free dyeing method which comprises the following steps of: soaking pre-swelled cotton fabric into reactive dye liquor, heating up to a primary dyeing temperature of 40-100 DEG C and keeping the temperature for 0-20 minutes, adding an organic solvent, heating up to a dyeing temperature of 60-100 DEG C and keeping the temperature for 0-20 minutes, adding soda ash, heating up to a fixation temperature of 40-100 DEG C and keeping the temperature for 30-60 minutes, cooling to room temperature, and carrying out washing, soaping and washing on the cotton fabric. The method is simple and easy to industrialize, is capable of obtaining dye-uptake and fixation rate higher than a traditional reactive dye dyeing process, has relatively good leveling property and is capable of realizing salt-free low-alkaline dyeing.

Description

Technical field [0001] The invention belongs to the field of reactive dye dyeing, and particularly relates to a reactive dye salt-free dyeing method. Background technique [0002] Reactive dyes have bright colors, complete chromatograms, and excellent wet processing fastness. They are the most important type of dyes for cellulose fiber dyeing. However, in order to improve the dye uptake and fixation rate, a large amount of inorganic salts are often used during the dyeing process. Salt is difficult to remove through simple physical, chemical and biochemical treatments, which brings a great burden to the environment. At present, the development of low-salt and salt-free reactive dyes is mainly centered on the synthesis of new dyes, the research and development of dyeing auxiliaries, fiber modification and the formulation of reasonable low-salt dyeing processes. [0003] Low-salt reactive dyes mainly reduce the amount of salt by increasing the molecular weight and coplanarity of the ...

AI Technical Summary

Problems solved by technology

[0003] Low-salt reactive dyes mainly improve the affinity of dyes and fibers by increasing the molecular weight and coplanarity of dyes, reducing the number of sulfonic acid groups, and introducing cationic groups to reduce the amount of salt. The problem with this method is that it is necessary to develop new types of dyes , The chromatogram is not easy to match, it is easy to dye unevenly, and it will increase the amount and cost of dyes

Substitute salts include sodium formate, potassium phthalate, EDTA, sodium citrate, polycarboxylate sodium salt, etc. The main problem is that it will increase the cost of dyeing, and it is difficult to enter the fiber when the molecular weight is large

The cationization method of cotton fiber mainly includes pretreatment of cotton fabric under alkaline conditions by connecting reactive amine compounds on cellulose fibers or using quaternary ammonium salts, but the cationization reagents with small molecular weights have poor directness and low dosage. However, the level dyeing and penetrating properties of macromolecular and polymer cationic reagents are significantly reduced, and the light fastness will also be reduced, and many cationic reagents themselves are not good for the environment.