Patent ID: 7588702

Claim:
A method of increasing the UV absorbing life of a sunscreen composition containing (a) a dibenzoylmethane derivative that reaches a singlet excited state or fluoresces when exposed to UV radiation and (b) a cinnamate ester comprising adding a compound of formula (I) in an amount effective to quench the singlet excited state energy from the dibenzoylmethane derivative and transfer the singlet excited state energy from the dibenzoylmethane derivative to the compound of formula (I) thereby returning the dibenzoylmethane derivative to its ground state so that the dibenzoylmethane derivative can absorb more photons from ultraviolet light before it undergoes a photochemical reaction destructive to its UV-absorbing capability thereby photostabilizing (a) and (b) wherein one of R 1 and R 2 is a straight or branched chain C 1 -C 30 alkoxy radical, and the non-alkoxy R 1 or R 2 is hydrogen; and R 3 is a straight or branched chain C 1 -C 30 alkyl radical.