acid dye

A chemical anionic dye used in dyeing protein fibres, including wool and silk, also polyamide fibres. This range of dyes is often referred to as brilliant dyes, are wet-fast and produce good results in fastness and brightness of colour. They can normally be applied in an acidic or neutral state. This large group of acid dyes, with a limited range of colours, is subdivided into four main classes:

• acid levelling or equalizing dyes
• acid milling dyes
• half milling or perspiration fast dyes
• super-milling or fast dyes