Continuous tone-on-tone dyeing method for knitted fabric by adopting active dye

Abstract

The invention discloses a continuous tone-on-tone dyeing method for a knitted fabric by adopting active dye. The method comprises the following steps of adding the same amount of clean water based on the total liquid amount in a preset bath ratio, and adding a piece of grey cloth to the mixed liquid for full wetting; adding salt, an accelerant and a levelling agent, which have the same concentration as that in a starting bath, to the clean water, and fully wetting the grey cloth; supplementing residual water of the starting bath with the clean water and preset original dye so as to reach the total liquid amount in the preset bath ratio; and feeding the wetted grey cloth into the residual water, supplemented with the clean water and the preset original dye, of the starting bath for dip dyeing. By virtue of full analysis on the components of the residual water of the starting bath, the problems of color mixing and dye hydrolysis which are caused by continuous dyeing by using the residual water of the starting bath are solved, so that the further reuse of a large amount of residual water of the starting bath is facilitated, and the effects of saving energy, reducing emission and the like can be achieved.

Description

technical field [0001] The invention relates to a continuous cylinder dyeing method for knitted fabrics dyed with reactive dyes of the same color and dark color. Background technique [0002] Most enterprises in our country follow the concept of dyeing knitted fabrics or yarns when doing reactive dye dyeing, first add dyes for level dyeing, and then add yuan Mingfen to promote dyeing. This process is reversible; if After adding alkali in sections, the chemical reaction between dye molecules and fibers occurs in the form of conjugate bonds or van der Waals forces. The basis of this theory is: firstly, too early and too fast adding of dyeing accelerator Yuanming powder (salt) will easily cause the initial dyeing rate to increase, and the dyed part will be dyed quickly. Second, premature addition of alkali agent in the dye solution may cause premature local chemical reaction of the dyed object, resulting in irreversible local uneven dyeing and hydrolysis of a large number of d...

AI Technical Summary

Problems solved by technology

Second, premature addition of alkali agent in the dyeing solution will easily cause local premature chemical reactions of the dyed object, resulting in irreversible local uneven dyeing, and at the same time causing a large number of dye molecules to hydrolyze

However, due to the large amount of salt, alkali, and dye residue in the water of the first vat, after the white gray cloth of the second vat is put into the vat, the concentration of salt, alkali, and dye solution in the vat is greater than the concentration of salt, alkali, and dye on the surface and inside of the fiber, resulting in a large amount of salt, alkali, and dye. Alkali and dye molecules quickly adsorb, diffuse, and permeate to the surface of the fabric and the interior of the fiber, and bond reactions occur quickly to cause color flowers in an instant

Due to the large amount of alkali contained in the dye solution and the high temperature for a long time, it is easy to cause the problem of hydrolysis of the dye