C.I. Direct brown 33

Direct brown 33 (C.I. 35520)

2,7-Naphthalenedisulfonic acid, 5-((diamino((8-hydroxy-6-sulfo-2-naphthalenyl)azo)phenyl)azo)-4-hydroxy-3-((4'-((4-hydroxyphenyl)azo)(1,1'-biphenyl)-4-yl)azo)-, trisodium salt