| abstract |
The use of substituted alpha -methylstyrene derivatives of the formula I, where the variables have the following meanings: R1 C4-C10-alkoxy, C1-C12-alkylamino, C1-C12-dialkylamino, substituents which confer solubility in water and which are selected from the group consisting of carboxylate, sulfonate or ammonium residues; R2 hydrogen, C2-C10-alkyl, C1-C12-alkoxy; R3 COOR5, COR5, CONR5R6, CN; R4 COOR5, COR5, CONR5R6, CN; where the substituents R3 and R4 are identical in each case; R5 and R6 independently of one another hydrogen, C1-C12-alkyl, C2-C10-alkenyl, C3-C10-cycloalkyl, C3-C10-cycloalkenyl, aryl, hetaryl, unsubstituted or substituted; as photostable UV filters in cosmetic and pharmaceutical preparations to protect the human skin or human hair from the sun's rays, alone or together with UV-absorbing compounds known per se for cosmetic and pharmaceutical preparations. |