Colour fastness
Colour fastness is a term—used in the dyeing of textile materials—that characterises a material's colour's resistance to fading or running. The term is usually used in the context of clothes. In general, clothing should be tested for colour fastness before using bleach or other cleaning products.
Light fastness, wash fastness, and rub fastness are the main forms of colour fastness that are standardised. The light fastness of textile dye is categorised from one to eight and the wash fastness from one to five, with a higher the number indicating better fastness.
