Synonyms: 2,7-Naphthalenedisulfonicacid, 3-hydroxy-4-[(2-hydroxy-6-sulfo-1-naphthalenyl)azo]- (9CI);2,7-Naphthalenedisulfonic acid,3-hydroxy-4-[(2-hydroxy-6-sulfo-1-naphthyl)azo]- (8CI);1-(2-Hydroxy-6-sulfo-1-naphthylazo)-2-naphthol-3,6-disulfonic acid;2,2'-Dihydroxy-1,1'-azonaphthalene-3,6,6'-trisulfonic acid; Biryuzon