Views: 0 Author: Site Editor Publish Time: 2021-10-13 Origin: Site
For dyeing and printing dark fabrics with reactive dyes, sulfide dyes and direct dyes. Especially black and bright red, sometimes the wet rubbing fastness is required to reach grade 3 or above. Especially for orders exported to Europe, America and Japan, the requirements for wet friction are more strict. Therefore, it is necessary to use additives to treat the dyed finished products, so as to improve the wet rubbing fastness by 1-2 levels, reaching level 3 or even above. How do they react to different types of wet rubbing fastness improvers?
Reaction type of wet rubbing fastness improver
1. Adsorption precipitation wet rubbing fastness improver
This type is generally cationic polymer compound.
Multiple quaternary ammonium salt cations form ionic bonds with dye anions to produce insoluble lakes. The treated color fixing agent forms a film on the surface of the dyed fabric. In addition, multiple hydroxyl groups in the color fixing agent can form hydrogen bonds with the hydroxyl groups in cellulose fibers to promote the color fixing effect.
Individually, chitosan prepared by chitin can also be used as precipitation type wet rubbing fastness improver in dye fixation. The insoluble precipitate is fixed on the fiber surface, closes the hydrophilic group of the dye, and increases the dye molecules, so as to improve the wet rubbing fastness.
2. Crosslinked wet rubbing fastness improver
There are reactive groups on the molecule that can react with groups on dye molecules and cellulose molecules at the same time. It can form a highly diversified crosslinking system between dyes and fibers. So that the dyes and fibers can be more firmly connected to prevent the dyes from falling off from the fibers. Moreover, free dyes can also be closely linked together, so as to improve the color fastness of dyes.
3. Film forming, covering and isolating wet rubbing fastness improver
The film-forming covering wet rubbing fastness improver can form a continuous film on the fabric surface to separate the dye from the fabric. Moreover, these polymer compounds generally have the function of softener, which can slow down the friction between the fabric and the test white cloth, so as to improve the wet friction fastness of the fabric.
For example, polyamine color fixing agent synthesized by dicyandiamide and polyethylene polyamine. A network structure film is formed on the surface of the fabric to improve the wet rubbing fastness.
4. Color fixing agent type wet rubbing fastness improver
The purpose of this kind of enhancer is to improve the active fixation rate to reduce floating color and improve the wet rubbing fastness.
5. Comprehensive wet rubbing fastness improver
This kind of dye improves the wet rubbing fastness of fabrics through one or more of the functions of fixation, film-forming, crosslinking, adsorption and precipitation.
For example: Polyurethane wet rubbing fastness improver. It can not only form a continuous smooth film on the surface of the fabric, but also cover the dye under the film. The active groups on its macromolecules can covalently bond with fibers and dyes under certain conditions to improve the dye fixation rate.
Wet rubbing fastness improver JV-536 is a polymer compound. Formaldehyde free. It is suitable for the fixation finishing of fabrics dyed with reactive, vulcanized, direct and vat dyes. It is applied to the washing of denim ready-made clothes, and the effect is very excellent.
matters needing attention
1. The chemical material cannot be heated, and it is best to use soft water. The prepared working fluid is semitransparent lotion at 25 degrees centigrade. Please use it immediately after preparation.
2. It must be used at low temperature, and the working fluid cannot be heated.
3. If it is used before the setting machine, the material shall be melted in the high-level tank and the mixing condition shall be maintained; It is better to add bubbling device to the material chute to prevent it from being used
Precipitation of color fixing agent; Cool before putting into the setting machine.
4. When used in the dye vat, the material shall be melted first, then added, and the good circulation of working fluid shall be maintained.