| 摘要 |
PURPOSE:To improve the plasticity of a molded article by hydrolyzing a metal alkoxide solution, adjusting the pH of the sol to a specific level and lowering and then raising the pH with an acid and an alkali to form a formed article. CONSTITUTION:A solution of a metal alkoxide is hydrolyzed with an acid to form a sol having a pH of 2-3. The pH of the sol is lowered to about 1.2-1.6 with nitric acid, etc., and then adjusted to 1.5-3.5 with an alkali. The sol of the above state is dried and cast to obtain a formed material of gelatinous thin film. Since the formed material is produced by the lowering and raising of the pH of the sol without using any organic binder, the processability of the formed material can be improved to prevent the damage and deformation of the material in processing. The plasticity of the formed article can be improved by this process. |
