The invention relates to the use of at least one specific triazine or melamine and/or salt thereof as accelerator for a photoinduced reaction of 3-(4-tert-butylphenyl)-3-hydroxy-1-(4-methoxyphenyl)-propan-1-one, 1-(4-tert-butylphenyl)-3-hydroxy-3-(4-methoxyphenyl)-propan-1-one or a mixture of these compounds to give avobenzone. The invention furthermore relates to a composition comprising at least one specific triazine or melamine and to a method for the stabilisation of the UV absorption capacity of a composition by means of a mixture of at least one specific triazine or melamine together with 3-(4-tert-butylphenyl)-3-hydroxy-1-(4-methoxyphenyl)propan-1-one, 1-(4-tert-butylphenyl)-3-hydroxy-3-(4-methoxyphenyl)propan-1-one or a mixture of these compounds, particularly preferably together with 3-(4-tert-butylphenyl)-3-hydroxy-1-(4-methoxyphenyl)propan-1-one.
