Leather Dyes Specialized Manufacturer
Ltd. is an acid dyes, direct dyes, leather dyes, feed additives and other chemical raw materials manufacturers, products are mainly used in leather, wool, tweed, silk, paper, wood, metal and other industry sectors.
Knowledge about Dyes! What are the applications and precautions of acid dyes?
Acid dyes refer to dyes that contain acidic molecules in their molecular structure, which can combine with the amino groups of proteins and fibers through ionic bonds. They can be applied under acidic, weakly acidic, or neutral conditions, and are water-soluble dyes with acidic groups in their structure, used for dyeing in acidic media. Most contain sodium sulfonate, are soluble in water, have bright colors, and a full range of hues.
Acid dyes have a complete spectrum, bright colors, and light and wet fastness that vary depending on the type of dye. Compared to direct dyes, acid dyes have a simpler structure and, due to insufficient planar structure length, cellulose fibers lack directness and cannot be used for cellulose dyeing. Different types of acid dyes vary in molecular structure, performance, and methods of use.
1. Classification
(1) Strong Acid Dyes
The first developed acid dyes, which require dyeing in a strong acid dye bath. They have a simple molecular structure, low molecular weight, and contain sulfonic or carboxyl groups. Their affinity for wool is not strong, allowing for uniform transfer, hence they are also referred to as acid dyes.
(2) Weak Acid Dyes
Weak acid dyes are generated from strong acid dyes by increasing molecular weight, introducing aromatic sulfonyl groups, or adding long carbon chains. Their molecular structure is more complex, they have a greater affinity for wool, do not damage the wool, have deep colors, improved color fastness, and are uniform.
(3) Acid Medium Dyes
A type of acid dye that forms metal complexes on fabrics after treatment with certain metal salts (such as chromium salts, copper salts, etc.) as mordants. The mordanting process is relatively complex, but it results in products with good light, wash, and abrasion fastness.
(4) Acid Complex Dyes
Composed of some acid dyes and metals like chromium and cobalt. They are soluble in water, and their dyes can be sun-exposed with good light fastness. The parent of this dye is similar to acid coal body dyes, but during the preparation of the dye, atoms are introduced into the azo dye molecules, with a metal atom to dye molecule ratio of 1:1, hence also called 1:1 metal complex dyes. There is no need for additional mordant treatment during dyeing.
2. Selection Guide:
Acid dyes are only suitable for fibers with positive charges. For example, cotton fibers can be dyed with acid dyes after cationization.
When dyeing with two types of dyes, the structure of the dye and the structure of cationic cotton play a dominant role. An increase in the number of groups on cationic cotton leads to better washing effects.
Latest developments
Dezhou Jinmao Chemical Co., Ltd.
Address: 1922 Yingbin Street, Lingcheng District, Dezhou City, Shandong Province, China
WhatsApp:
Focus on GLIDE