Chemical name: 2,2-(1,4-phenylene)bis-4H-3,1-benzoxazin-4-one CAS No.:18600-59-4 Molecular formular:C22H12N2O4 Molecular weight:368.34 Appearance: White to off-white crystalline powder Melting point,degree:310min. Assay, %: 98min. Ash, %: 0.1max. Loss on Drying: 0.5max. UV ABSORBER HOSORB-UV3638 is a highly efficient benzoxazinone type UV absorber, which is distinguished by its superior low volatility and strong & broad range of UV light absorption together with no color contribution & excellent stabilization for polymers. It� is designed to meet the demanding high temperature requirements for processing engineering plastics such as Nylon, PC,PET,PBT and PPO. It is also highly effective in other polymers such as polyamides, polyacetals, polyolefins fibers, styrenics, elastomers where long term UV light stability is required.