Also Called: Benzenesulfonic acid, 4,4'-[1,3-phenylenebis[azo( 4,6-diamino-3,1-phenylene)azo]]bis-, disodium salt;Benzenesulfonic acid, 4,4'-[1,3-phenylenebis[2,1-diazenediyl(4,6-diamino-3,1-phenylene)-2,1-diazenediyl]]bis-, sodium salt (1:2);Benzenesulfonic acid, 4,4'-[1,3-phenylenebis[azo(4,6-diamino-3,1-phenylene)azo]]bis-, disodium salt