It is in combination with a HALS for the light stabilization of LDPE and LLDPE as well as EVA copolymers for agricultural films. It can be used as well as a UV barrier to protect the contents of packages for both industrial and consumer applications. Also, in combination with HALS, RIASORBUV-531 can be used in HDPE molded articles e.g. in crates. RIASORBUV-531 also protects a number of other polymers against degradation caused by light exposure such as plasticized PVC and rubbers. RIASORBUV-531can be used in combination with antioxidants, phosphites and light stabilizers.