초록 |
To apply for liquid crystal alignment layer of vertically aligned liquid crystal display (VA-LCD), surface energy controlled photo-reactive polyimide films were synthesized. Three photo-reactive polyamic acids were prepared from alicyclic dianhydride, cyclobutane-1,2,3,4-tetracarboxylic dianhydride [CBDA], and functional diamines, 4,4'-diaminodiphenylmethane [MDA], 3,5-diaminobenzyl 3-(biphenyl-4-yl)acrylate [DA-BIP] and 1-(3,5-diaminophenyl)-3-octadecyl-pyrrolidine-2,5-dione [DA-L-18IM], respectively. We have blended photo-reactive polyamic acids and irradiated linear polarized UV on the hybrid films. Optically anisotropy and birefringence of alignment layer were investigated by photo elastic modulator. We have also studied electro-optic properties of LCD cell fabricated with the linear polarized UV irradiated hybrid films, which showed very high pretilt angle and good electro-optic properties. |