Also Called: C.I. acid red 112;2,7-Naphthalenedisulfonic acid, 3-hydroxy-4-[[2-sulfo-4-[ (4-sulfophenyl)azo]phenyl]azo]-, tetrasodium salt;2,7-Naphthalenedisulfonic acid, 3-hydroxy-4-[[2-sulfo-4-[(4-sulfophenyl)azo]phenyl]azo]-, tetrasodium salt;2,7-Naphthalenedisulfonic acid, 3-hydroxy-4-[2-[2-sulfo-4-[2-(4-sulfophenyl)diazenyl]phenyl]diazenyl]-, sodium salt (1:4)