The correct selection of dyes is a key factor in improving the uniformity of nylon dyeing. There is a wide range of dyes available for dyeing nylon fibers, among which dispersed dyes, anionic dyes such as acid dyes, 1:2 metal complex dyes, and preferred direct dyes are important.

Disperse dyes with simple molecular structures can mask physical and chemical differences in nylon fibers due to their non-ionic properties and low molecular weight, but this dye can only achieve moderate color fastness. Disperse dyes with complex structures can have good wet fastness when dyeing nylon fibers, but due to their high molecular weight, they can only mask chemical differences and cannot mask physical differences. The preferred direct dyes bring superior wet treatment fastness to nylon dyeing, and are economical for producing dark colored products. Compared with dispersed dyes, dyeing with bright dyes can obtain relatively more bright colored products (with better shade than dispersed dyes). Acid dyes are commonly used for nylon dyeing. Their advantages include easy coloring, deep color, simple dyeing procedures and requirements, good wet fastness of the dyed product, but poor uniformity compared to dispersed dyes.

The leveling ability of various dyes on nylon fibers is generally as follows: dispersion dyeing>acid dyes>reactive dyes>neutral dyes>direct dyes. At present, acid dyes such as Tectilon, ErionylA, LanaSet, and low-temperature disperse dyes are commonly used for nylon with good dyeing performance and high color fastness.

Article source: Nylon colored yarn

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