tetrasodium 3,3'-[carbonylbis[imino(2,5-dimethyl-4,1-phenylene)azo]]bisnaphthalene-1,5-disulphonate 3,3'-[Carbonylbis[imino(2,5-dimethyl-4,1-phenylene)azo]]bis(1,5-naphthalenedisulfonic acid)tetrasodium salt 3,3'-[Ureylenebis[(2,5-dimethyl-4,1-phenylene)azo]]bis[naphthalene-1,5-disulfonic acid disodium] salt C.I.29030 C.I.Direct Yellow 51 Carta Yellow RW