Synonyms: tetrasodium 7,7'-[carbonylbis[imino(3-methoxy-4,1-phenylene)azo]]bisnaphthalene-1,3-disulphonate;7,7'-[Carbonylbis[imino(3-methoxy-4,1-phenylene)azo]]bis(1,3-naphthalenedisulfonic acid)tetrasodium salt;1,3-Naphthalenedisulfonic acid, 7,7'-(carbonylbis(imino(3-methoxy-4,1-phenylene)-2,1-diazenediyl))bis-, sodium salt (1:4);1,3-Naphthalenedisulfonic acid, 7,7'-(carbonylbis(imino(3-methoxy-4,1-phenylene)azo))bis-, tetrasodium salt;Einecs 269-353-8