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CN-122013567-A - After-finishing process for improving light color fastness of fabric

CN122013567ACN 122013567 ACN122013567 ACN 122013567ACN-122013567-A

Abstract

The invention discloses a post-finishing process for improving the light color fastness of a fabric, which comprises the following steps of S1, preparing a modified fabric, S2, adding epoxy modified waterborne polyurethane emulsion, modified titanium dioxide, 2-ethyl-4-methylimidazole and fatty alcohol polyoxyethylene ether into deionized water, uniformly stirring to obtain a finishing liquid, and S3, padding the pretreated fabric in the finishing liquid, and performing post-treatment on the padded fabric. According to the process, the surface of the polyester fabric is modified, the thiol functional group with high reactivity is introduced, and meanwhile, the modified titanium dioxide is added, so that a highly stable three-dimensional network coating between the fabric, the polyurethane and the titanium dioxide is formed under high-temperature baking through the bridging effect of epoxy modified waterborne polyurethane in the finishing process, and the added modified titanium dioxide not only effectively inhibits photodegradation of dye caused by illumination and ultraviolet radiation, but also remarkably improves the illumination color fastness of the fabric.

Inventors

  • ZHU YANFENG
  • HONG DAN

Assignees

  • 浙江正达纺织科技有限公司

Dates

Publication Date
20260512
Application Date
20260228

Claims (10)

  1. 1. The after-finishing process for improving the light color fastness of the fabric is characterized by comprising the following steps of: S1, adding dyed polyester fabric into a sodium hydroxide solution, then adding a modifier, carrying out dipping treatment, filtering and washing after finishing the treatment, then adding the polyester fabric into an ethanol water solution, adding gamma-mercaptopropyl trimethoxy silane, carrying out stirring reaction, taking out after finishing the reaction, and drying to obtain a modified fabric; s2, adding the epoxy modified waterborne polyurethane emulsion, modified titanium dioxide, 2-ethyl-4-methylimidazole and fatty alcohol polyoxyethylene ether into deionized water, and uniformly stirring to obtain finishing liquid; And S3, padding the pretreated fabric in finishing liquid, and performing post-treatment on the padded fabric.
  2. 2. The finishing process according to claim 1, wherein the modifier in step S1 is prepared by adding 20-30 parts by weight of tetrabutylammonium bromide to 100 parts by weight of ethylene glycol, adding 15-25 parts by weight of benzyl alcohol, 10-20 parts by weight of sodium polyacrylate, 2-3 parts by weight of disodium edetate, and stirring at 40-60 ℃ for 30-50 min.
  3. 3. The finishing process according to claim 1, wherein in the step S1, the mass concentration of the sodium hydroxide solution is 0.5-1%, the feed liquid ratio of the polyester fabric to the sodium hydroxide is 1:20-30, the addition amount of the modifier is 1-2% of the mass of the polyester fabric, the temperature of the impregnation treatment is 50-60 ℃, and the time is 30-40min.
  4. 4. The finishing process according to claim 1, wherein the volume ratio of ethanol to water in the aqueous ethanol solution in step S1 is 90-95:5-10, the addition amount of the gamma-mercaptopropyl trimethoxysilane is 4-5% of the mass of the polyester fabric, the temperature of the stirring reaction is 60-70 ℃, and the time is 2-3 hours.
  5. 5. The post-finishing process according to claim 1, wherein in the step S2, the raw materials in the finishing liquid are 50-60 parts by weight of epoxy modified aqueous polyurethane emulsion, 5-8 parts by weight of modified titanium dioxide, 0.5-0.8 part by weight of 2-ethyl-4-methylimidazole, 1-2 parts by weight of fatty alcohol polyoxyethylene ether and 200 parts by weight of deionized water.
  6. 6. The finishing process of claim 1, wherein the modified titanium dioxide in step S2 is prepared by the following method: Adding titanium dioxide into ethanol water solution, adding vinyl triethoxysilane, heating for reaction, filtering, washing, and drying to obtain ethylene titanium dioxide, adding ethylene titanium dioxide into DMF, adding 5-amino-2-mercapto benzimidazole, and azodiisobutyronitrile, reacting at constant temperature, filtering, washing, and drying to obtain modified titanium dioxide.
  7. 7. The finishing process according to claim 6, wherein the volume ratio of ethanol to water in the ethanol aqueous solution is 4-5:1, the mass ratio of titanium dioxide to vinyltriethoxysilane is 100:7-10, the heating reaction is carried out at 50-60 ℃ for 4-6 hours, the mass ratio of the vinylated titanium dioxide to the 5-amino-2-mercaptobenzimidazole to the azodiisobutyronitrile is 100:8-11:0.1-0.2, and the constant temperature reaction is carried out at 70-80 ℃ for 3-4 hours.
  8. 8. The finishing process according to claim 1, wherein the padding treatment in step S3 is performed by two padding and the padding residual ratio is 70-85%.
  9. 9. The finishing process according to claim 1, wherein the post-treatment in step S3 is drying and baking, the temperature of drying is 90-110 ℃, the temperature of baking is 160-170 ℃ and the time is 2-3min.
  10. 10. A fabric produced by the finishing process of any one of claims 1-9.

Description

After-finishing process for improving light color fastness of fabric Technical Field The invention belongs to the technical field of fabric finishing, and particularly relates to a post-finishing process for improving the light color fastness of a fabric. Background Polyester (polyethylene terephthalate) fibers are widely used in the field of textile and clothing because of their excellent physical and mechanical properties, dimensional stability, easy care and other advantages. However, polyester fibers have regular molecular structures, high crystallinity, lack of active functional groups on the surfaces, and are chemically inert, which results in poor dyeing properties. In order to obtain vivid colors, polyester dyeing is usually carried out by using disperse dyes under the conditions of high temperature and high pressure or the existence of carriers. Although the disperse dye is the main dye of the polyester, the molecular weight of the disperse dye is smaller, and the disperse dye is combined with polyester fibers mainly by virtue of physical effects such as Van der Waals force, dipole effect and the like, and lacks chemical bond connection. Meanwhile, the molecular structure of the disperse dye generally contains chromophoric groups such as azo or anthraquinone, and the chromophoric groups are easy to undergo photooxidation or photoreduction reaction under long-term irradiation of sunlight, particularly ultraviolet rays, so that a chromophoric system is damaged, and the problems of fading or color change of the fabric are caused. Therefore, the polyester fabric, especially the product dyed with bright, medium and light colors, has generally low light color fastness, which limits the application in the fields of outdoor clothing, automobile interior trim, curtains and the like with high requirements on light resistance. In order to improve the light color fastness of the polyester fabric, an after-finishing method is generally adopted in the industry. One common technique is treatment with ultraviolet absorbers. For example, ultraviolet absorbers such as benzotriazoles and benzophenones are applied to the fabric surface by padding or coating. However, the ultraviolet absorbent of the small molecules is only physically adsorbed to the fiber, so that the binding fastness is poor, and the light-resistant function of the ultraviolet absorbent is not durable due to easy loss in the wearing and washing processes. In addition, during the finishing process, the auxiliary agents are also easy to migrate from the finishing liquid to the surface of the fabric, so that uneven distribution is caused, and the finishing effect and the appearance of the fabric are affected. Another technique is to use film-forming resins (such as polyurethane or acrylic ester) to finish the coating, and physically coat the dye molecules on the surface of the fiber to isolate the contact with light and oxygen. The method has the defects that firstly, the adhesion between a common resin coating and the surface of chemically inert polyester is poor, the coating is easy to peel off after repeated washing and friction, so that the color fastness is reduced, secondly, the original soft hand feeling and air permeability of the fabric are seriously affected by the excessively thick resin coating, so that the fabric becomes stiff and stuffy, and finally, the ultraviolet shielding capability of a pure resin film is limited, and the damage of high-energy photons to dye molecules cannot be fundamentally prevented. Therefore, developing an after-finishing technology which can firmly combine the functional coating on the surface of the polyester fiber, not only can remarkably and permanently improve the color fastness of light, but also does not sacrifice the original excellent hand feeling and style of the fabric is a technical problem to be solved in the field. Disclosure of Invention Aiming at the defects of the prior art, the invention aims to provide a post-finishing process for improving the light color fastness of the fabric. In order to achieve the above purpose, the present invention provides the following technical solutions: a post-finishing process for improving the light color fastness of a fabric comprises the following steps: S1, modifying the fabric, namely adding the dyed polyester fabric into a sodium hydroxide solution, then adding a modifier, carrying out dipping treatment, filtering and washing after the treatment is finished, then adding an ethanol water solution, adding gamma-mercaptopropyl trimethoxy silane, carrying out stirring reaction, taking out after the reaction is finished, and drying to obtain the modified fabric; s2, preparing a finishing liquid, namely adding epoxy modified waterborne polyurethane emulsion, modified titanium dioxide, 2-ethyl-4-methylimidazole and fatty alcohol-polyoxyethylene ether into deionized water, and uniformly stirring to obtain the finishing liquid; S3, finishing the fabric, namely padding