Ultraviolet absorber UV-531 belongs to benzophenone ultraviolet absorber, its chemical name is 2- hydroxy -4- n-octyloxy benzophenone, and it is light yellow needle crystal powder at room temperature. It is an efficient anti-aging additive with excellent performance, which can strongly absorb ultraviolet light at 270 ~ 340 nm. It has the characteristics of light color, non-toxicity, good compatibility, low mobility and easy processing, and is widely used in PE, PVC and PP. But also provides good light stabilization effect for dry phenolic and alkyd varnishes, polyurethanes, acrylics, epoxies and other air-dried products, automobile refinishing paints, powder coatings, polyurethanes, rubber products and the like.