Abstract: A fully automated computer controlled system and method to simultaneously measure in a dynamic mode the streaming potential, impedance and permeability resulting from a flow of various liquids through a sample, particularly a compressed mass of human hair. The system includes four air-pressurized reservoirs and three test cells, each test cell containing a sample to be tested. An impedance measurement is made by impressing a signal wave train across each sample over a selected range of frequencies, preferably in the 10-10,000 Hz range, rather than at a single frequency. The air pressure is controlled within 2% of a selected pressure and the outlet flow of liquid from the test cells is continually measured to provide an accurate and reproducible set of measurements.

Abstract: Disclosed are improved topical compositions having improved efficiency such as improved sunscreen effectiveness for protecting the skin from the harmful effects of ultraviolet irradiation, such as sunburn and sun-induced premature aging of the skin.

Abstract: The present invention relates to oil-in-water emulsion compositions useful for imparting an artificial tan to human skin. These emulsions contain paucilamellar lipid vesicles, i.e. vesicles comprising several concentric lipid bilayers, encapsulating an aqueous dihydroxyacetone solution. The vesicles comprise a polyoxyalkylene alkyl ether, a sterol, a quaternary ammonium compound, and optionally, a non-surface active oil. In further embodiments, these emulsion compositions contain one or more sunscreens, and are also useful for protecting human skin from the harmful effects of sunlight and other sources of ultraviolet radiation. The present invention also relates to methods for preparing these compositions, methods for providing an artificial tan to human skin, and methods for protecting human skin from the harmful effects of ultraviolet radiation.