| abstract |
Compounds represented by the following general formula: wherein Rf and Rf' mean a perfluoroalkyl group having 1-20 carbon atoms or a ( omega -H-perfluoroalkyl group represented by the formula H(CF2)t in which t stands for an integer of 1-20, R2 denotes a hydrogen atom, a straight-chain or branched aliphatic hydrocarbon group having 1-20 carbon atoms, an alicyclic or aromatic hydrocarbon group having 5-10 carbon atoms, a perfluoroalkyl group having 1-20 carbon atoms, or omega -H-perfluoroalkyl group represented by the formula H(CF2)u- in which u stands for an integer of 1-20, X and Y mean individually a single bond, -CO- or a divalent hydrocarbon group having 1-6 carbon atoms, l stands for a number of 2-16, and m and n are individually a number of 1-6. The compounds are useful for preparing fluorine-modified silicone derivatives suitable for cosmetic compositions. |