METHOD FOR PREPARING A PHOTO-CROSSLINKABLE COMPOSITION

摘要

The invention relates to a photo-crosslinkable composition that can be obtained by a method including the following steps: (a) the hydrolysis and condensation reaction of a [(epoxycycloalkyl)alkyl]-thalkoxysilane in solution in an organo-aqueous medium containing water in an initial water/monomer molar ratio of between 3 and 15, with at least one water-soluble solvent, at a pH of between 1.6 and 4.0, by heating the solution to a temperature of between 50 and 70°C for a duration of between 180 and 350 minutes in order to obtain a solution of an organo-mineral hybrid prepolymer, in which the totality or quasi-totality of the alkoxysilane groups has been hydrolysed, and which comprises in average at least 4 (epoxycycloalkyl)alkyl groups; (b) cooling the polyepoxide prepolymer composition thus obtained down to a temperature of between 15 and 25°C; (c) adding to said composition at least one cationic-polymerisation photo-primer and at least one photosensitiser having a maximum absorption at a wavelength of between 300 and 420 nm, and optionally adding a surfactant; (d) agitating the composition thus obtained for a duration of between 10 and 120 minutes at a temperature of between 15 and 25°C; (e) filtering the composition thus obtained with a filter comprising pores with an average size of between 1 and 5 µm; and (f) storing the liquid filtrate thus obtained at a temperature lower than 0°C, preferably between -20 and -10°C. The invention also relates to the use of such a photo-crosslinkable composition as a negative photosensitive resin in a photolithography process.