Patent ID: 7928179
Filing Date: 2011-04-19
Classification: C08G,C08L,Y10T

Abstract:
1. A method for preparing a photoreactive group-containing siloxane compound, comprising the steps of subjecting a system comprising (a) a photoreactive group-containing alkoxysilane selected from photoreactive group-containing alkoxysilanes having the following general formulae (1) and (2): wherein each of R 1 to R 5 is an alkyl group of 1 to 4 carbon atoms or acetyl group, each of a and b is an integer of 1 to 3, and mixtures thereof, with the proviso that if component (a) is a single alkoxysilane, it is a trialkoxysilane, and if component (a) is a mixture of alkoxysilanes, it contains at least 70 mol% of a trialkoxysilane, (b) a hydrolyzable group end-capped dimethylsiloxane having the general formula (6): wherein R 6 is hydrogen, methyl or ethyl, A is an oxygen atom or ethylene, n is an integer of 5 to 100, and x is an integer of 1 to 3, and (d) an alcohol to hydrolytic condensation in the presence of a basic catalyst and with an amount of water greater than the amount necessary for hydrolytic condensation of all alkoxy groups, rendering the resulting system neutral, and distilling off the alcohol.