Abstract: The hair treatment method includes applying to hair an effective amount of aqueous, alcoholic or aqueous-alcoholic hair treatment composition containing from 0.05 to 15 percent by weight of at least one as-yet-uncrosslinked hydrolytic precondensation product for forming an inorganic-organic hybrid polymer and optionally at least one film-forming hair-setting polymer, and subsequently crosslinking the as-yet-uncrosslinked hydrolytic precondensation product while the as-yet-uncrosslinked hydrolytic precondensation product remains on the hair to form the inorganic-organic hybrid polymer in order to provide long-lasting good hair setting. The hydrolytic precondensation product has an Si—O—Si network and is made by hydrolytically condensing at least one organosilane having crosslinkable groups with or without a network-modifying compound for modifying the crosslinking of the crosslinkable groups.

Abstract: Object of the invention is the use of at least one inorganic-organic hybrid prepolymer in cosmetic agents and the use of inorganic-organic hybrid prepolymers or crosslinked inorganic-organic hybrid polymers in the treatment of hair, skin or nails.