Kain Industrial Additives: Introduction to Application Classification of Dyes

Categories are based on the application objects of dyes, dyeing methods, application performance and combination forms with dyed substances.

(1) Acid dyes and acid combined dyes Acid dye molecules contain acidic groups such as sulfonic acid groups and protecting groups, or salts of organic carboxylic acids. The dyeing process must be completed in an acidic or neutral dye bath, and is mainly used for dyeing protein fibers and polyamide fibers. During dyeing, the acidic group of the dye combines with the propanol or amide group in the fiber structure to dye the fiber. After some dyes are treated with metal mordants, they can form metal combinations in the fibers and be fixed on the fibers.

(2) Basic dyes The dye molecules contain basic groups, such as amino groups or substituted cyano groups, which can form salts with the rib groups on protein fibers and directly dyeing.

(3) Direct dye molecules contain acidic water-soluble groups and are mainly used for dyeing cellulose fibers. During dyeing, hydrogen bonds are formed between dye molecules and cellulose molecules.

(4) Sulfur dyes Sulfur dyes are insoluble in water. Because they need to be dyed in sulfide alkali solution, they are called sulfur dyes. Mainly used for dyeing cotton fibers.

(5) Neutral dyes Neutral dyes are metal complex dyes. Because they are dyed in a nearly neutral dye bath, they are called neutral dyes. dye. Used for dyeing vinylon, silk, silk, wool, etc.

(6) Ice dyes Ice dyes are composed of diazo components and coupling components, which react on the fiber to form insoluble azo dyes. Since ice is used under cooling conditions during dyeing, ice dyeing is mainly used for dyeing cotton fibers.

(7) Vat dyes. These dyes are insoluble in water. They are dyed by reducing them to soluble leuco bodies in alkaline solutions with a reducing agent (insurance powder). After oxidation, the leucobody is transformed into a water-insoluble dye in the fiber. It is mainly used for dyeing cellulose.

(8) Indigosol and lysine are soluble vat dyes, mainly used for cotton printing, and a small amount for silk, Hair dyeing.

(9) Reactive dyes contain reactive groups in the molecular structure of the dye, which chemically combine with the hydroxyl or amino groups on the fiber molecules during dyeing, so it is called a reaction. Sex dyes or reactive dyes are mainly used for printing and dyeing cotton, linen, silk and other fibers, and are also used for dyeing wool and synthetic fibers.

(10) Disperse dyes do not contain water-soluble groups in the dye molecules. They need to be ground into very fine particles and dispersed in water in the presence of a dispersant. Dyeing, so it is a disperse dye. It is mainly used for dyeing hydrophobic synthetic fibers (such as polyester, nylon, acetate, etc.).

(11) When dyeing with cationic dyes. This type of dye dissolves in water and combines with the dyed fiber in a cationic form, so it is called a cationic dye. Mainly used for dyeing wax fiber.

(12) Other dyes such as food dyes, leather dyes, and developing polypropylene dyes, fluorescent dyes, etc.