Abstract: The invention relates to a method for determining an integral sun protection factor (? SPF or iSPF) which encompasses both UVA and UVB radiation and can be used for classifying cosmetic and dermatological sunscreens. The method comprises the steps of applying a defined amount of the sunscreen onto a defined area of a skin substrate impregnated with a spin trap, exposing the skin substrate to a defined amount of UVA- and UVB rays by a sun simulator, subjecting the skin substrate exposed to radiation to an electron spin resonance (ESR) measurement, recording the number of free radicals trapped as a real number×1012 free radicals/mg of skin sample, and determining the integral sun protection factor ? SPF according to the equations (1) and (2) and (8) ? S ? ? P ? ? F = E 0 E ( 1 ) log 10 ? ( E ) = a · log 10 ? ( X · 1000 ) + b ( 2 ) E = 10 log ? ? 10 ? ( E ) .

Abstract: The invention relates to a method for determining an integral sun protection factor (?SPF or iSPF) which encompasses both UVA and UVB radiation and can be used for classifying cosmetic and dermatological sunscreens. The method comprises the steps of applying a defined amount of the sunscreen onto a defined area of a skin substrate impregnated with a spin trap, exposing the skin substrate to a defined amount of UVA- and UVB rays by a sun simulator, subjecting the skin substrate exposed to radiation to an electron spin resonance (ESR) measurement, recording the number of free radicals trapped as a real number×1012 free radicals/mg of skin sample, and determining the integral sun protection factor ?SPF according to the equations (1) and (2) and (8) ? S ? ? P ? ? F = E 0 E ( 1 ) log 10 ? ( E ) = a · log 10 ? ( X · 1000 ) + b ( 2 ) E = 10 log ? ? 10 ? ( E ) .

Abstract: The invention relates to a new method for determination of realistic UV protection factors or bread spectrum indices of a sunscreen preparation. Realistic UV protection factors are calculable by determination of the theoretical and the experimental UV absorbances of known UV filters in wavelength steps of about 5 nm in the range of 290-400 nm from a definite basic formulation (emulsion, gel etc.) and on a transparent substrate and introducing of the values in a mathematical model. These factors are in conformity with values measured in vivo. The number of the experiments for developing new formulations are significant reduced because only basic formulation, kind and concentration of the filters have to enter.

Abstract: The invention relates to a new method for determination of realistic UV protection factors or bread spectrum indices of a sunscreen preparation. Realistic UV protection factors are calculable by determination of the theoretical and the experimental UV absorbances of known UV filters in wavelength steps of about 5 nm in the range of 290-400 nm from a definite basic formulation (emulsion, gel etc.) and on a transparent substrate and introducing of the values in a mathematical model. These factors are in conformity with values measured in vivo. The number of the experiments for developing new formulations are significant reduced because only basic formulation, kind and concentration of the filters have to enter.

Abstract: The invention relates to a stable multiple phase emulsion of the O.sub.1 /W/O.sub.2 type with high proportions of the primary O.sub.1 /W emulsion. The new emulsions have an emulsifier-free primary oil-in-water phase consisting of a viscoplastic aqueous gel containing the finely distributed inner oil droplets together with a gelling agent, wherein the thixotropic primary oil-in-water phase has a yield point in the range from 20 to 100 Pa and a plastic viscosity of 0.01 to 0.1 Pa.multidot.s and contains at least one lipophilic agent in the primary oil; and a secondary oil phase in which the primary oil-in-water phase is present together with a lipophilic emulsifier; and wherein the proportion of the inner oily phase is from 10 to 35 % by weight relative to the total weight of the emulsion. The higher proportions of the inner oily phase render possible higher proportions of organic sun protection agents with simultaneous avoidance of skin irritations.

Abstract: A multi-phase sunscreen agent, characterized by at least two phases that are liquid to pasty or gelatinous and separate from each other spontaneously within seconds to less than ten minutes after a brief and gentle mixing process lasting less than one minute without any essential application of force, where at least one phase contains a UV filter.

Abstract: The invention relates to a novel process for the preparation of stable complex multiple emulsions of the water-oil-water type which are well suited for use in cosmetic preparations. The primary emulsions of the W/O type are prepared in the presence of both a non-ionic polymeric lipophilic emulsifier and a non-ionic polymeric stabiliser each preferably having an HLB value in the range from 6 to 10. In a second process step more water containing a hydrophilic emulsifier having a higher HLB value, preferably in the range from 12 to 25, is added to the primary emulsion until phase inversion occurs. It is important that the procedure in this second process step is not reversed, i.e. that the primary emulsion is not added to the aqueous phase. Further active substances, such as UV filters and vitamins, may be added to the aqueous or oil phase respectively.