2,7-Naphthalenedisulfonic acid, 4,5-dihydroxy-3-(phenylazo)-, disodium salt 4197-07-3 Acid Chromotrope 2R Acid Red 29 Acilan Chromotrope RR Brasilan Fast Fuchsine G C.I. 16570 C.I. Acid Red 29 C.I. Acid Red 29, disodium salt Chromotrope 2R Chromotrope Red 2R Cromatrope 2R Fast Fuchsin G Fast Fuchsine G Hispacid Fuchsin G NSC7829