Synonyms: 3,3'-[carbonylbis[imino(2-methyl-4,1-phenylene)azo]]bisnaphthalene-1,5-disulphonic acid;1,5-naphthalenedisulfonic acid, 3,3'-[carbonylbis[imino(2-methyl-4,1-phenylene);1,5-Naphthalenedisulfonic acid, 3,3'-[carbonylbis[imino(2- methyl-4,1-phenylene)azo]]bis-;3,3'-[Carbonylbis[imino(2-methyl-4,1-phenylene)azo]]bis(1,5-naphthalenedisulfonic acid)