Pure cotton black cheese dyeing process applied to vinyl sulfone type reactive dye

Abstract

The invention discloses a cheese pure-cotton low-alkali dyeing process applied to a vinyl sulfone type reactive dye. The cheese pure-cotton low-alkali dyeing process comprises the following steps of (1) pretreatment: carrying out pretreatment on pure-cotton cheese by adopting a refining agent; (2) dyeing: adding an anhydrous sodium sulphate aqueous solution into a main cylinder, and then carrying out heating circulation for four times of forward circulation and three times of backward circulation; then adding the active black dye into the main cylinder, heating and circulating, and then heating and circulating; (3) fixation: dissolving a dyeing partner into an aqueous solution, adding the aqueous solution into the main cylinder, then carrying out heat preservation circulation, depressurizing, sampling and color matching; and (4) performing subsequent treatment: performing washing and softening after the liquid is discharged when the standard is detected. According to the process, low-alkali, neutralization-free, less soaping and less hot water washing times are realized, the working time is shortened, and more importantly, the emission of COD (Chemical Oxygen Demand) is reduced. The quality of the obtained pure cotton black cheese achieves relatively low layer difference and good color fastness, particularly, the wet rubbing color fastness is obviously higher than that of a traditional process, and the market competitiveness is improved.

Description

technical field [0001] The invention relates to the technical field of cotton dyeing, in particular to a pure cotton black cheese dyeing process applied to vinyl sulfone type reactive dyes. Background technique [0002] The demand for black pure cotton cheese in the global market accounts for about 30% of the total production of cotton cheese, and vinyl sulfone type black series reactive dyes are the dominant dyes in the dyeing of pure cotton cheese. The reaction process of vinyl sulfone reactive dye dyeing cotton is: under alkaline conditions, the vinyl sulfone sulfate group on the reactive dye molecule first undergoes an elimination reaction to form a vinyl sulfone group, and then reacts with the (alkalined) primary on the cellulose The nucleophilic addition reaction of the alcoholic hydroxyl group produces a dye-fiber covalent bond. Scientific experiments have proved that this is a secondary chemical reaction. The side reaction is the hydrolysis reaction with water molec...

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Problems solved by technology

However, this method is not effective when applied to relatively thick cheese yarns, and it is easy to cause color difference between the outer yarn and the inner yarn.

[0007] Chinese invention patent 2014106532242 A method of low-alkali dyeing of black regenerated cellulose fiber cheeses using 5g / L sodium carbonate as a color-fixing alkali agent, using vinyl sulfone-type reactive dyes to dye black regenerated cellulose fiber cheeses Successful, but unsuccessful dyeing of natural pure cotton cheese, due to differences and limitations in the dyeing properties of high-purity cellulose fibers regenerated by chemical methods in the composition and properties of natural cotton fibers

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