The presently claimed invention relates to additive mixture comprising a compound of formula (1) and a compound of formula (2). The presently claimed invention further relates to a composition comprising an organic material which is susceptible to oxidative, thermal or light-induced degradation and the additive mixtures. The presently claimed invention also relates to a method for stabilization of organic materials by incorporating therein or applying thereto the additive mixtures. Further, the presently claimed invention relates to the use of the additive mixtures as light stabilizer for organic materials.