Definition: the so-called acid dye is a kind of containing acid group, in acid, the weak acid, neutral in the bath with fiber and
protein can have a direct polyamide fibers of a class of anionic dyes.
Structural features: dye molecular structure is relatively simple, mostly single-azo dyes, for a small number of dual-azo dyes, in the absence of a longer conjugated double bonds, aromatic elements of plane or linear features is not strong, So the lack of affinity for
cellulose fiber.
Application features: acid dyes by a full, bright color, and other characteristics. Wet fastness and the sun and fastness with different varieties and are very different. One relatively simple structure, with more acid-wet fastness on the poor.
Category: According to the chemical structure of acid dyes, dyeing and dyeing process of the different conditions, acid dyes can be divided into three categories, including strong acid, neutral and with weak acid bath of acid dye staining.
Application for: acid dyes many varieties, mainly for wool, silk and other protein fiber
polyamide fibers and dyeing and printing, can also be used for leather, ink, paper and cosmetics and food coloring pigment.
Do you know Acid Dyes ? 
