Optical brightener OB-1 is mainly used for lanon and widely applied ... ABS, PS, HIPS,PA,PC, EVA and hard PVC etc. Optical brightenerchemical name: 2,2-(4,-4'-vinyl biphenyl) dual benzoxazoleCAS ... whitening agent for PET,PBT, PP fibers, widely applied to ABS, PS, HIPS,PA,PC, EVA and hard PVC etc. optical brightener OB ...