Direct Dyeing
Direct dyes are generally soluble in water because they contain water-soluble groups in their molecular structure. There are also a few dyes need to add some soda ash to help dissolve, he can not rely on other additives and direct dyeing of cotton, linen, silk, wool and viscose and other fibers, so called direct dyes. Direct dyes complete color spectrum, bright colors, low prices, easy dyeing methods, color uniformity, but its color fastness to washing is poor, color fastness to sunlight is not good. In addition to light colors, generally have to solid color treatment.

Reactive dyestuff dyeing
Reactive dyes are water-soluble dyes containing one or more reactive groups (also called reactive groups) in the molecule. Under certain conditions, they can be chemically combined with hydroxyl group in cellulose, amino group and amide group in protein fiber and nylon, so reactive dyes are also called reactive dyes.

Reducing Dye Dyeing
 Reducing dyes (trade name serin dyes) are insoluble in water, and when dyeing, they have to be reduced and dissolved into sodium salt of cryptochrome in alkaline reducing solution before dyeing fibers, and then oxidized so that they can be re-transformed into the original color precipitates and fixed on the fibers.
Reduction dyestuffs have full chromatography and bright color, and they are excellent dyestuffs in every performance, especially in sunlight resistance and color fastness to washing for other dyestuffs, but they are more expensive, with fewer red varieties, poorer color fastness to rubbing when dyeing thick colors, and some yellow-orange dyestuffs have light-sensitive brittle phenomenon, so their use is restricted to a certain extent.

Soluble Reduction Dye Dyeing
Soluble reducing dyes, also known as Indicotin dyes, are mostly derived from reducing dyes. Soluble reduction dyes are soluble in water, have certain affinity to cellulose fiber, good diffusibility and even dyeing of dyes, high color fastness to rubbing, good color fastness to sunlight, washing and perspiration.

Sulfur dyes dyeing
Sulfur dyes contain sulfur, it can not be directly dissolved in water, but can be dissolved in sulfide alkali, so it is called sulfide dyes. Sulfide dyes are simple to manufacture, inexpensive, simple dyeing process, easy to spell color, dyeing fastness is better, but the chromatography is not complete, mainly blue and black-based, color and luster is not bright, and the fiber has a brittle effect.