We have studied liquid crystal (LC) alignment on UV-irradiated poly(vinyl cinnamate)(PVCi)films by using the texture observations and the anchoring energy measurements. Irradiation of the PVCi films with linearly-polarized UV light creates the optical anisotropy in the films, and the anisotropy can well align LCs perpendicular to the UV polarization. We discuss the LC alignment mechanisms and point out the important contribution from non-dimerized side chains of PVCi molecules. The anchoring energies on photo-processed PVCi films are shown to be smaller than those on conventional rubbed polyimide films. We propose a new method to generate pretilt angle on the photo-processed PVCi films, and successful results of pretilt angle generation are demonstrated. This method is applied to fabricate TN- and super-multidomain TN-LCDs, and the good electro-optical performance of the LCDs is confirmed.

Super twisted nematic (STN) liquid crystal displays(LCDs) using spiral polymer aligned nematic (SPAN) liquid crystals have been achieved by photo-polymerization of some kinds of chiral monoacrylates in liquid crystalline hosts.The spiral polymer made of a chiral monoacrylate in STN LCD has effect to reduce the driving voltage without any disadvantages for the STN LCD. The relation of chemical structure of a chiral monoacrylate and nature of spiral polymer is discussed.