31319916optical brightenerPT2026-03-30 20:26:13UF31319917FWANDUF31319918brightener, opticalNDUF31319919fluorescent bleachNDUF31319920fluorescent brightenerNDUF31319921fluorescent whitenerNDUF31319922fluorescent whitening agentNDUF31319923optical bleachNDUF31319924optical brightenersNDUF31319925optical whitenerNDBT31305866bleachPT