An Acid Dye is a dye, in chemical regard a sodium (less often–ammonium) salt of a sulfonic, carboxylic or phenol organic acid. Acid dye is soluble in water and possesses affinity for amphoteric fibers while lacking direct dyes' affinity for cellulose fibers. When dyeing, ionic bonding with fiber cationic sites accounts for fixation of colored anions in the dyed material. Acids are added to dyeing baths to increase the number of protonated amino-groups in fibers.

Some acid dyes are used as food colorants.

Used In :

• Paper
• Nylon
• Silk  Yarn And Textiles Dyeing
• Lab Stains
• Inks

Characteristic :

• Good Solubility
• Good Levelling property
• Several are suitable for high temp application /  blend dyeing