TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: Alternately, glycidol and mercapto group-containing alkoxysilane partial condensate, are subjected to dealcoholization reaction, to obtain alkoxy group-containing mercapto group-containing silane modified phenol resin. The obtained modified phenol resin is made to conjugate a solid acid such that the mercapto group is oxidized and sulfonated, to obtain the proton conductive material. The proton conductive material is dissolve or dispersed in a solvent, to obtain solution or sol. The resulting solution or sol is subjected to gelatinization, and the solvent is removed from the solution or sol. EXAMPLE - Glycidol (in g) (200) and methyl silicate 56 (tetra methoxysilane partial condensate) (1997.6), were stirred. Dibutyl tin dilaurate was added to the resulting mixture and reacted at 90degreesC under nitrogen atmosphere. The reaction mixture was cooled for 6 hours after distilling methanol. The resulting mixture was maintained for 20 minutes under 13 kPa and cooled to room temperature, to obtain glycidyl ether group-containing alkoxysilane partial condensate (2110.2) having epoxy equivalent of 782 g/eq. KP7516 (ortho cresol novolak resin) (700), methyl ethyl ketone (600) and 2-methyl imidazole (2) were added to the obtained condensate (683.9) and reacted at 85 degrees C for 4 hours. The reaction mixture was cooled to 80 degrees C, to obtain alkoxy group-containing silane modified phenol resin solution (A) having phenolic hydroxyl equivalent of 400 g/eq. Tungstic acid (100) was dissolved in tetrahydrofuran, to obtain solution (B). The solution (A) was added to the solution (B) and stirred, to obtain solution (C). The resulting solution (C) was applied on a substrate, to obtain a film with thickness 100 mum. The resulting film was dried at 90 degrees C for 1 hour, hardened at 210 degrees C for 2 hours and cooled to room temperature, to obtain a gel film with thickness of 30 mum. The obtained gel film had proton conductivity of 4x10-3 S/cm.