The so-called dyeing fastness (referred to as color fastness) refers to the degree of fading of dyed fabrics under external factors (such as extrusion, friction, washing, rain, exposure, light, saliva impregnation, water stains, sweat stains, etc ) during use or processing. The color fastness test of textile is a routine item in the intrinsic quality test of textile.

The test of color fastness generally includes light fastness, weather fastness, color fastness to washing, color fastness to friction, color fastness to perspiration, etc. Generally, when color fastness test is conducted, it refers to the degree of discoloration of dyes and the degree of staining on the lining. For color fastness rating, except for Lightfastness, which is grade 8, the rest are grade 5. The higher the level, the better the color fastness.

Dyeing fastness can be used to indicate the nature or degree of variation in dyeing state. The dyeing fastness of a fabric is related to the type of fiber, yarn structure, fabric structure, printing and dyeing methods, type of dye, and external force.