SUNSCREEN COSMETIC COMPOSITIONS, ITS PREPARATION AND ITS USE

摘要

Cosmetic compsns. for topical use, esp. for protecting the skin and/or hair from the effects of light, comprise metal oxide nano-pigments (i.e. pigment particles with an average size of 100 nm or less) dispersed in an o/w emulsion with an aq. oil droplet size of 100-1000 nm. Also claimed is a process for preparing the above compsn. comprising: (a) mixing an oil phase with an aq. phase in the presence of an emulsifier at a temp. above the phase inversion temp. of the system to form a w/o emulsion; (b) reducing the temp. below the phase-inversion temp. to form an ultrafine o/w emulsion; and (c) adding the nano-pigments during step (a) and/or after step (b). Also claimed is a cosmetic treatment process for protecting the skin and/or hair against UV radiation, esp. solar radiation, comprising applying a compsn. as above.