To suspend temporarily the duty on 2,7-Naphthalenedisulfonic acid, 5-[[4-chloro-6-[[2-[[4-fluoro-6-[[5-hydroxy-6-[(4-methoxy-2- sulfophenyl)azo]-7-sulfo-2-naphthalenyl]amino]-1,3,5-triazin 2-yl] amino]-1-methylethyl]amino]-1,3,5-triazin-2-yl]amino]-3-[[4- (ethenylsulfonyl)phenyl]azo]-4-hydrox'-, sodium salt.