Cosmetic or dermatological formulations comprising at least one particulate UV filter substance and at least one dialkyl naphthalate having the structural formula ##STR00001## wherein R.sup.1 and R.sup.2 are selected independently of one another from the group consisting of branched and unbranched alkyl groups having 6 to 24 carbon atoms, are useful for protecting skin from harmful effects of solar radiation, particularly from UV-A and UV-B radiation.