Diamino compounds represented by general formula (1); a polyamic acid and a polyimide both obtained from any of the diamino compounds; and an alignment film made from the polyimide. The alignment film is obtained by irradiating a film of the polyimide with polarized ultraviolet. (In general formula (1), G1 represents a C2-20 trivalent organic group; G2 independently represents a single bond, - COO-, -NHCO-, -O-, -S-, etc.; G3 represents a single bond or C1-20 alkylene; X and Y each independently represents hydrogen, fluorine, cyano, C1-12 alkyl, C3-8 cycloalkyl, etc.; and m is an integer of 0 to 3).
通用公式(1)表示的二
氨基化合物;从任何二
氨基化合物获得的聚
酰胺酸和聚
酰亚胺;以及由聚
酰亚胺制成的取向膜。 取向膜是通过用偏振紫外线照射聚
酰亚胺薄膜获得的。(在通用公式(1)中,G1表示C2-20三价有机基;G2独立表示单键,-COO-,-NHCO-,-O-,-S-等;G3表示单键或C1-20烷基;X和Y各自独立表示
氢,
氟,
氰基,C1-12烷基,C3-8
环烷基等;m为0到3的整数)。