A composition containing a diester of a naphthalene dicarboxylic acid having compound formula (I) for photochemically stabilizing dibenzoylmethane derivatives, absorbing UV radiation, imparting gloss and for stabilizing natural hair color and hair dyes against fading, and which can be used to increase the emolliency and sunscreen protection factor (SPF) of cosmetic formulations and for filtering out ultraviolet radiation from human skin:wherein R1 is has the formula (II)wherein k is 1 to 13, preferably 1 to 6, most preferably 1, and R2, same or different, is selected from the group consisting of a compound of formula (II) wherein k is 1 to 13, preferably 1 to 6, most preferably 1, and an alkyl group, straight chain or branched, having 1 to 22 carbon atoms, and mixtures thereof. These diesters of formula (I) are quite effective in stabilizing the dibenzoylmethane derivative UV-A filter compounds making them more effective, and effective for longer periods of time.