| 摘要 |
PURPOSE: To obtain a polyimide excellent in liquid-crystal alignment, etc., and suited for use as a liquid-crystal alignment film by reacting two specific diamino compounds with a specific tetracarboxylic dianhydride and heating the resultant poly(amic acid). CONSTITUTION: A diamino compound represented by formula I (wherein R<1> is a 1-20C alkyl) (e.g. ethyl 3,5-diaminobenozate) is reacted with a diamino compound represented by formula II (wherein (m) is 1-20; (n) is 1-2; and R<2> is a 1-20C alkyl or alkoxy) e.g. 4-(trans-4-ethylcyclohexyl)phenoxypropyl)3,5 diaminobenzoate} and the tetracarboxylic dianhydride represented by formula III in a solvent to yield a polyamic acid. This acid is heated to obtain a polyimide comprising 5-95mol% structural units represented by formula IV and 95-5mol% structural units represented by formula V. |
