Dyeing method of natural fibers in supercritical carbon dioxide fluid

Abstract

The invention discloses a natural fiber dyeing method in a supercritical carbon dioxide fluid. A natural fiber textile is placed in a supercritical carbon dioxide dyeing unit, which is dispersed with reactive dyes and in a dissolving state; the dyes are adsorbed uniformly on the fiber, and fully diffused in the fiber; and a catalytic fixation of the dyes on the fiber is realized in a 1.0-6.0 MPa carbon dioxide gas medium and with existence of a dye fixation catalyst. According to the invention, dye up-take and dye fixation reaction are conducted in different units and under different conditions, so a side reaction between a large amount of dyes, which are not absorbed, in a fluid and the dye fixation catalyst is avoided, when a dyeing and a dye fixation are carried out in a same bath. Therefore, utilization rate of the dyes and dye fixation catalysis efficiency of the catalyst to the dyes on the fiber during the dye fixation reaction are both increased. The technical method of the present invention has advantages of high dye fixation efficiency, high dye utilization rate, simple technology, green and environment friendliness.

Description

technical field [0001] The invention relates to a natural fiber dyeing method in supercritical carbon dioxide fluid, in particular to a dyeing method in which disperse reactive dyes are used in supercritical carbon dioxide fluid to carry out dyeing and color fixing reactions on natural fibers respectively, which belongs to the textile industry. Dyeing and finishing technology field. Background technique [0002] Supercritical carbon dioxide fluid is a green and environment-friendly fluid medium. It replaces the traditional water bath for dyeing and processing fiber textiles. It has the characteristics of environmental protection and clean production, as well as outstanding energy-saving and consumption-reducing effects. The status quo of high resource consumption, large amount of sewage discharge, and serious environmental pollution is of great significance. [0003] At present, synthetic fiber textiles such as polyester, nylon, acetate, acrylic fiber, and polypropylene fib...

AI Technical Summary

Problems solved by technology

However, the use of a large amount of solvent or organic wetting and bulking agent to pretreat the fiber takes a long time, and the residue on the fiber needs to be further processed, and the remaining solvent or auxiliary agent needs to be separated and recovered, which increases the complexity of the process. It also prolongs the process flow, and puts forward higher requirements for the explosion-proof safety of processing equipment

Although the fiber modified by the modifier can improve the fixation rate of the dye, it may also change the original natural quality of the natural fiber and affect its wearability

Adding acid to the supercritical carbon dioxide fluid can make the color fixing reaction between the dye active group and the fiber easier, but it also reduces the solubility of the dye in the supercritical carbon dioxide fluid, thereby affecting the dyeing of the dye on the fiber. amount and color yield, and the utilization rate of disperse reactive dyes in hydrophobic fluids will also decrease after protonation; in addition, the acidified supercritical carbon dioxide fluid also puts forward higher requirements on the corrosion resistance of equipment; at the same time, it is necessary to obtain higher For a good dyeing effect, the dyeing processing time is often longer (4 hours or longer), indicating that the acid's role in promoting the color fixing reaction is still not ideal

Images