| 摘要 |
PURPOSE: A liquid crystal alignment agent is provided to form a liquid crystal alignment film which does not cause the deterioration of a display performance even if driven for a long time. CONSTITUTION: A liquid crystal alignment agent comprises (a) polyamic acid A and (b) polyamic acid B. The polyamic acid A is obtained by reacting tetracarboxylic dianhydride with diamines having a photoreactive structure. The polyamic acid B is obtained by reacting at least one kind of tetracarboxylic dianhydride selected from the group consisting of 1,2,3,4-cyclobutanetetracarboxylic dianhydride and pyromellitic dianhydride with at least one kind of selected from the group consisting of 2,2'-dimethyl-4,4'-diaminobiphenyl, p-phenylenediamine, 4,4'-diaminodiphenylmethane, and 4,4'-diaminodiphenylether. |
