Chemical name: 2- (2'-Hydroxy-5'-tert-octylphenyl)benzotriazole CAS No.:3147-75-9 Molecular formular:C20H25N3O Molecular weight:323 Appearance: White powder Melting point,degree:103-105 Assay (HPLC), %: 99min. Ash, %: 0.1max. Loss on drying, %: 0.3max. Transmittance 450nm 98%min. 500nm 99%min. UV ABSORBER HOSORB-329 is excellent benzotriazole ultraviolet absorbent with effective absorption of ultraviolet radiation in 270-380 nm region. It is suitable for polyester, rigid PVC, PS, PMMA, PC, ABS resin etc. It is particularly suitable for the protection of polycarbonates. In transparent products and high temperature processing of engineering plastics, its effect is excellent. It can also be used for polyolefin.