Abstract
Transparent vinylsilsesquioxane-titania (ViSiO3/2-TiO) hybrid gel films were prepared from vinyltriethoxysilane and titanium tetrabutoxide by the sol-gel method. UV light irradiation partly cleaved Si-C bonds and addition-polymerized C=C bonds to form Si-O-Si and Si(CH2)nSi linkage in the hybrid films due to the photosensitizing effect of TiO component. The refractive index and dynamic hardness of the hybrid films increased, and the thickness and contact angle for water decreased by the structural changes induced by the UV light irradiation. In comparison with several kinds of organosilsesquioxane-titania (RsiO3/2-TiO, R=methyl, ethyl, phenyl and benzyl) hybrid gel films, ViSiO3/2-Ti,sub>2 was found to show the largest increase in hardness due to the formation of Si(CH2)nSi linkage. Micropatterning was successfully performed on the ViSiO3/2-TiO hybrid films by UV light irradiation through a photomask. The patterned film can be applied as a printing plate with the surface energy differences as well as a micro-optical component with the surface profiles and refractive index differences.
