Dyeing method adopting activated dye with high fixation rate

Abstract

The invention relates to a dyeing method adopting an activated dye with a high fixation rate. The dyeing method comprises the steps as follows: firstly, a water / organic solvent co-solvent system is adopted to enable the activated dye to dye cotton fabrics; after dyeing is completed, the water content on the fabrics is reduced through changing dye bath or evaporation; organic alkali and inorganic alkali are added for fixation for a certain period at a certain temperature; and after the fixation is completed, the fabrics are subjected to washing, soaping, washing and drying. The technical scheme adopted by the invention has a simple technology, convenience in operation and no special requirement for dye and equipment, large-scale production can be performed by conventional equipment, the solvent is easy to recycle, and salt-free and low-alkaline dyeing can be achieved; and meanwhile, hydrolysis of the dye on the fabrics can be reduced, so that the dye can be fixed on fibers, the environmental pollution and the production cost are reduced, and the dyeing method has wide application prospect.

Description

technical field [0001] The invention belongs to the field of reactive dye dyeing methods, in particular to a dyeing method with high color fixation rate of reactive dyes. Background technique [0002] Reactive dyes can be covalently bonded with cellulose fibers, which can endow fabrics with excellent wet fastness. In addition, their bright colors and complete chromatograms have become the most important type of dyes for cellulose fiber dyeing. Reactive dyes are generally fixed on cotton under alkaline conditions, and the hydroxide ion OH in the dyeing solution - It can also undergo a nucleophilic reaction with the dye to generate a hydrolyzed dye, thereby reducing the color fixation rate of the dye (the color fixation rate is generally only 50% to 80%). Hydrolyzed dyes cannot react with cotton and have little affinity for fibers. In order to obtain dyed products with high wet fastness, they must be washed out in the washing process. Washing requires a lot of water, resultin...

AI Technical Summary

Problems solved by technology

Dyes with high directness and high fixation rate are not easy to be washed off after hydrolysis, which will affect the color fastness and uniformity of dyeing; dyeing under low-alkali or neutral conditions requires the development of new dyes or changes in the dyeing process, such as increasing temperature and Increase the electrolyte concentration; cold-batch dyeing technology can increase the utilization rate of dyestuff by 10% to 15%, but the control of the production process is strict, the controllability of shade is poor, and the residual sodium hydroxide can easily cause the fabric to feel hard and the tear strength to decrease and other defects; low liquor ratio dyeing can reduce the amount of salt used and increase the dye uptake rate, but the requirements for equipment are high; a large number of neutral electrolytes can easily cause salt pollution; fabric pretreatment modification has better wet treatment fastness degree, but the shade will become darker and the light fastness will decrease; the use of cationic color fixing agent can increase the dyeing depth of the fabric, but it will reduce its wet rubbing fastness; reactive color fixing agent will release formaldehyde, and the wet rubbing fastness is still not enough Ideal, color change and other issues