| abstract |
(57) [Summary] [Purpose] To obtain an alignment film which is rubbing-less and has excellent durability. [Structure] A polyamic acid was prepared from pyromellitic dianhydride and bis (4-aminophenyl) ether using N-methylpyrrolidone as a solvent, and this solution was added with a 2-fold molar amount of p- 2-Aminoethylphenyl-p-methoxycinnamate is added to form a photocrosslinkable polyamic acid ammonium salt. This solution is spin-coated on a glass substrate with ITO to a thickness of about 1000Å, and then an aqueous solution of polyvinyl alcohol is further coated and dried. Using linearly polarized UV light with a wavelength of about 3200Å as the light source for exposure, After curing, the substrate is immersed in water and then a mixed solution of dilute hydrochloric acid, tetrahydrofuran and N-methylpyrrolidone to remove the polyvinyl alcohol and the cross-linked site. |