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This paper describes a flexible monostabilized ferroelectric liquid crystal (FLC) device using molecularly aligned polymer walls and networks, which are sequentially formed with a two‐step photopolymerization‐induced phase separation. When ultraviolet (UV) light was irradiated through a photomask onto a heated nematic phase solution of FLC and monomer, monomer molecules that had flowed into the irradiated areas were photopolymerized, and polymer walls aligned along the rubbing direction of the polyimide alignment layers on plastic film substrates were formed. After uniform UV irradiation without a photomask, polymer networks aligned along the rubbing direction were formed in the FLC. The FLC molecules were monostabilized in the rubbing direction by the strong anchoring of the polymer networks. The device, which was sandwiched between crossed polarizers, exhibited a monostable electro‐optic characteristic with a high contrast ratio of over 100:1 and a response time of less than 1 ms. The FLC device exhibit...

This paper discusses thermal phase transitions in a nematic liquid crystal material, filling a highly strained porous polyolefin film. Ruptured and aligned polymer fibrils, whose minimum diameter reaches several tens of nm, formed polymer networks in the porous film. From observations of temperature-controlled composite films using a polarizing microscope, it was noted that the isotropic-to-nematic phase transition temperatures of submicron liquid crystal domains, located in or near molecularly aligned streak-like polymer areas, were significantly higher than those located at some distance from these areas. It was assumed that the highly aligned polymer chains in the fine fibrils promote the nematic phase of the liquid crystal. The stretched porous polymer, exhibiting spatial ordering on a submicron scale, is thus suitable for the control of thermal phase transitions in a liquid crystal.

This paper describes the alignment of ferroelectric liquid crystal (FLC) structures formed between aligned polymer fibres, where the FLC smectic layers are determined by polarising microscopy and X-ray diffraction. The FLC/polymer composite films were formed from a nematic phase FLC/monomer solution using a photopolymerisation-induced phase separation method. It was found that bending of the FLC smectic layers was induced in both the film plane and the cross-sectional plane at the phase transition from smectic A to chiral smectic C of the FLC material. The light transmittance properties of the composite film between crossed polarizers was analysed by light propagation simulation in several optical anisotropic media, based on the evaluated smectic layer model.