OPTICAL FILM AND LIQUID CRYSTAL DISPLAY DEVICE

摘要

An optical film wherein fixing of liquid crystal alignment can be easily accomplished, which optical film can realize a wavelength dispersion of low birefringence and from the industrial point of view, is inexpensive and can be easily produced. The optical film enables accurate regulation of optical characteristics, such as wavelength dispersion of birefringence, to desired value and enables fixing of desired alignment state, being uniform and able to attain area expansion. In particular, an optical film comprising a polyester comprising structural units derived from 1,1'-bicyclohexyl-4,4'-dicarboxylic acid and structural units derived from an aromatic diol compound of ortho form, wherein the state of alignment created at thermal aligning of the polyester is fixed by cooling to temperature of not above the glass transition temperature.