( Aniline 2: 5 Disulphonic Acid ) Synonyms: 2-amino 1, 4-benzenedisulphonic acid, 2, 5 disulfoaniline, 4-sulphometanilic acid Empirical Formula: C6H7N S2O6 CAS no.: 98 - 44 - 2 Appearance: Moist White Powder Applications: Intermediate for Optical Brightening Agents and for dyes like Direct Blue 70, 78, 82, 83, Direct Black 77, Direct Green 20, Direct Red 103, Film Orange P ( by) , Mordant Azol Printing Bordeaux B, Pigment Saturn Yellow 5 GL etc.