Synonyms: barium 3-[(1-hydroxy-2-naphthyl)azo]naphthalene-1,5-disulphonate;3-[(1-Hydroxy-2-naphthalenyl)azo]-1,5-naphthalenedisulfonic acid barium salt;1,5-Naphthalenedisulfonic acid, 3-((1-hydroxy-2-naphthalenyl)azo)-, barium salt (1:1);1,5-Naphthalenedisulfonic acid, 3-(1-hydroxy-2-naphthalenyl)azo)-, barium salt (1:1);1,5-Naphthalenedisulfonic acid, 3-(2-(1-hydroxy-2-naphthalenyl)diazenyl)-, barium salt (1:1);Einecs 268-058-1