Colorfastness definition is that the ability to keep original dye color under the influence of other kinds of external factors in the use processes of dyeing textiles. Or we can define color fastness like this: Color fastness refers to the resistance of color to fade or bleed of a dyed or printed textile materials to various types of influences e.g. water, light, rubbing, washing, perspiration etc. It is an important indicator to measure the quality of dyeing products.
Colour fastness of textiles refers to the degree of fading for dyed or printed fabrics under the influence of external factors (extrusion, friction, washing, rain, sun exposure, light, seawater impregnation, saliva impregnation, water impregnation, sweat impregnation, etc.) in the process of use or processing. It is an important index of fabrics. If colour fastness is good, textiles are easy to fade in the process of post-processing or use; Poor colour fastness will lead to the fading or staining of textiles, which will spoil the beauty of wear, and harm health.
The quality of colour fastness of textiles is not unfamiliar to most consumers, for example, black jeans turn grey after being washed twice, new socks dye your soles, white bottom shirts are “polluted” by dark sweaters, and silk dresses become colourless after being washed only once. These quality problems related to colour fastness have been bothering us, and are also major issue of consumer complaints. From this year’s spot checks of textiles and clothing by various national quality supervision departments, the unqualified colour fastness occurs frequently.
Testing for colorfastness is an essential step in cleaning any fabric. Whether you plan on washing a new pair of jeans or spot cleaning an upholstered chair, knowing how your fabric will react to the product in which you are going to use is essential. It will also a prevent a possible disaster in the washing machine when colors from one garment can bleed onto all the other clothes in the same load.
