Congress 107 – S 2415 – A bill to suspend temporarily the duty on black SCR stage, 2,7-naphthalene disulfonic acid, 4-amino-3-[[4-[[-4-[(2 or 4 -amino-4 or 2-hydroxyphenyl)azo]phenyl]amino]-3-sulfophenyl] axo]-5-hydroxy-6-(phenylazo)-trisodium salt.