| 摘要 |
PURPOSE:To obtain a solution film forming method for realizing a small difference of a solute distribution between the top and rear surfaces and a superior physical quality using a three-component solution of a solvent, a polymer, and a low-molecular solute without remarkably lowering a productivity. CONSTITUTION:In a solution film forming method in which a film is produced by casting and drying a high-molecular solution of a solvent, a polymer, and a solute on a substrate, the salute is selected so that an interaction parameter chibetween the low-molecular solute and the polymer can be not more than 0.9. In the drying process, a solvent/polymer weight ratio on the film surface is maintained to be not less than 0.12 until the weight ratio of the solvent to the polymer in the casted film reaches 23%. As an alternative method, the molar volume of the low-molecular salute is not more than 270cm<3>/mole. |
