Views: 1104 Author: Site Editor Publish Time: 2022-12-05 Origin: Site
Cellulose fibers such as pure cotton are usually dyed with anionic water-soluble dyes such as direct dyes and acid dyes. These dyes have a complete color spectrum and bright colors. But, because the structure of this type of dye has a water-soluble group, therefore, the dye is hydrophilic, and when washed, the color on the clothes is prone to fading and fading. The process of fading will make the appearance of the clothes old; at the same time, the dye will be hydrolyzed into the dye solution and will stain the cotton clothes, resulting in staining and color matching.
Speaking of this, first of all, I would like to introduce a concept to everyone, solid color. As the name implies, color fixation is to improve the color fastness of fabrics; and additives that can improve the color fastness of various types are called color fixers. Next, I will systematically explain how to solve the problem of fading and staining of cotton clothes from the source.
The working mechanism of color fixing agent:
The first is that dyes are dyed on different fibers, and the dyeing mechanism and color fastness are different, so the mechanism and application of the color fixing agent are also different.
(1) Use cationic groups such as quaternary ammonium salts or tertiary amine salts in the color-fixing agent molecule to bond with the anionic group in the structure of the ionic dye, so that the dye and the color-fixing agent form insoluble color blocks and deposit on the fiber , thereby improving the color fastness of the dye on the fabric.
(2) Use the reactive groups in the fixing agent molecules to cross-link with the reactive groups on the dye molecules and the hydroxyl groups on the cellulose molecules to reduce the water solubility of the dyes.
(3) Utilize the film-forming performance of the color fixing agent on the fabric to improve its color fastness. During the high-temperature drying process of the fabric treated with the color-fixing agent, the reactive cross-linking groups on the molecules of the color-fixing agent are self-crosslinked into macromolecules, forming a protective film with a certain strength on the surface of the fabric and fiber, wrapping the dye Cover the fiber, so that the dye is not easy to fall off.
Types of color fixing agent
From the principle of color fixing agent, color fixing agent can be divided into two categories: reactive color fixing agent and non-reactive color fixing agent.
Reactive color-fixing agent refers to the introduction of reactive groups into the molecules of the color-fixing agent. Epoxy groups are commonly used. This type of color-fixing agent can form covalent bonds with certain groups in fiber dye molecules. The improvement of color fastness is more favorable. Non-reactive color fixing agent refers to two types of film-forming and blocking water-soluble groups on the fiber surface, and its main types are divided into cationic color fixing agent and resin color fixing agent.
Daily Laundry Protection
1. Use care laundry detergent: Laundry detergent is easier to rinse, not easy to fade, does not hurt hands, and prevents static electricity; laundry detergent generally contains softener, so it is softer, more comfortable, and brighter than washing powder.
2. Reverse drying method: Turn the clothes to dry in reverse, which can prevent the ultraviolet rays from directly irradiating most of the fabrics and causing fading, especially for some dark clothes. For brightly colored clothes, try to dry the clothes in a dark and ventilated place.
3. For black, red and blue clothes that are easy to fade, it is best to soak and wash them separately.
As consumers, all we can do is pay attention to daily washing protection. If pure cotton clothes are not easy to fade, it is best to choose mid- to high-priced clothes. The fabrics of mid-to-high priced clothes will basically have solid color, and the color of the clothes will be longer-lasting, brighter and more comfortable to wear.