2,7-Naphthalenedisulfonic acid, 4-amino-3,6-bis[[4-[(2,4-diamino-5-methylphenyl)azo]phenyl]azo]-5-hydroxy-, disodium salt 6745-67-1 Artificial Silk Black R C.I. 35260 C.I. Direct Black 28 C.I. Direct Black 28, disodium salt Columbia Fast Black V Cutamin Black CV NSC75917 Rayon Black R