Synonyms: 2,7-Naphthalenedisulfonicacid,4-[[4-[(3,6-disulfo-1-naphthalenyl)azo]-7-sulfo-1-naphthalenyl]azo]-3-hydroxy-,pentasodium salt (9CI); 2,7-Naphthalenedisulfonic acid,4-[[4-[(3,6-disulfo-1-naphthyl)azo]-7-sulfo-1-naphthyl]azo]-3-hydroxy-,pentasodium salt (8CI)