, chemical name 5-amino-2-chloro toluene-4-sulfonic acid, is normally called C-acid, It is an important intermediate to synthesize red organic dyestuff. Industrially mainly used to synthesize Lake Red C. and widely used in coloration of paint, dope ,ink, rubber and plastic. This product has the similar speciality with commonly aromatic hydrocarbon, almost no poisonous. It is produced subject to Japan Industrial Standard JISK4147-88.