小特集 「フラットパネル・カラーディスプレイ」
配向膜材料
1990 年 27 巻 6 号 p. 472-477
詳細
1990 年 27 巻 6 号 p. 472-477
Various kinds of organic materials have been examined for alignment films. Among them, aromatic polyimides were chosen for their mechanical strength, heat- resistance and solvent- resistance. Aromatic polyimide must be baked at temperatures higher than 300°C. At such high temperatures, colored filters composed of organic polymer and dyes were damaged. Therefore, an alignmemt film which could be handled at temperatures lower than 180°C was expected. Japan Synthetic Rubber Co. has developed a new aliphatic cyclic polyimide which could be easily soluble in organic solvents like γ-butyrolactone, N-methylpyrrolidone for an alignment film of AM·LCDs. A thin film could be easily made using this soluble polyimide solution after evaporating solvent at temperatures lower than 180°C. Moreover, electric properties and anchoring energy of this aliphatic cyclic polyimide were excellent in comparison with other structure polyimides. On the other hand, alignment films for STN·LCD must have a high pretilt angle of 6-10°. As a result, new type polyimides consisting of polyimide and alkylamine with long alkyl chains were developed.
