Abstract: An optical element which exhibits a great improvement in durability even after repeated use. The optical element comprising a substrate having thereon (a) a recording layer comprising a liquid crystal polymer composition and (b) a surface protective layer in this order, in which the protective layer comprises a plurality of layers laminated such that the hardness thereof increases from the layer adjacent to the recording layer toward the uppermost layer in order, or the protective layer comprises a plurality of layers laminated such that the glass transition point thereof becomes higher from the layer adjacent to the recording layer toward the uppermost layer in order. Furthermore, the layer adjacent to the recording layer preferably has a pencil hardness of HB or higher and the uppermost layer preferably has a pencil hardness of 3 H or higher.

Abstract: A light modulation device with high density, high sensitivity, and excellent stability while having a simple construction and a non-destructive memory reading method using the same are disclosed. The light modulation device comprises a high polymeric liquid crystal film comprising a uniaxially orientated side chain type high polymeric liquid crystal containing a photochromic compound, and it modulates light in the wavelength region in which the photochromic compound has no absorption by making use of a change in refractive index anisotropy of the high polymeric liquid crystal film which has been caused by photoisomerization of the photochromic compound. The device is useful as a stable and high-density optical computing device or an erasable optical memory material.

Abstract: An erasable display medium comprising a substrate having thereon at least one liquid crystal polymer layer comprising a side chain type liquid crystal polymer which repeatedly and reversibly switches from a transparent state and a light-scattered state by the action of at least one of heat, an electrical field, and a magnetic field is disclosed, said side chain type liquid crystal polymer being a copolymer comprising a repeating unit represented by formula (I): ##STR1## and a repeating unit represented by formula (II): ##STR2## or a copolymer comprising a repeating unit represented by formula (III): ##STR3## and a repeating unit represented by formula (IV): ##STR4## wherein R.sup.a and R.sup.

Abstract: A reversible display medium comprising substrate 1 having thereon recording layer 2 containing a side chain type high polymeric liquid crystal capable of repeatedly and reversibly switching between a transparent state and a light-scattered state by the action of heat, an electrical field or a magnetic field, wherein said side chain type high polymeric liquid crystal is a copolymer comprising at least one liquid crystal monomer unit and at least one non-liquid crystal monomer unit having a hydrogen bond-forming substituent, e.g., a hydroxyl group, a carboxyl group, a sulfonic group or a phosphoric group. The display medium is excellent in durability on repeated use, heat sensitivity, display contrast, and record preservability.

Abstract: A liquid crystal-polymer composite film comprising a polymeric substance carrying a liquid crystal component and a non-liquid crystal component in the side chain thereof and having dispersed therein a low-molecular weight liquid crystal compound and an optical modulation element using the composite film are disclosed. The composite film can be driven at a low voltage and exhibits hysteresis.

Abstract: A liquid crystal-polymer composite film comprising (1) a high-molecular weight compound containing at least one kind of monomer units providing a side chain having a liquid crystal nature and at least one kind of monomer units providing a side chain having no liquid crystal nature and (2) a low-molecular weight liquid crystal, the high-molecular weight compound (1) and the low-molecular weight liquid crystal (2) being in separate phases, and the monomer units providing a side chain having no liquid crystal nature being crosslinked; and an electro-optical element comprising a pair of substrates each having an electrode having interposed therebetween a liquid crystal-polymer composite film comprising (2) a low-molecular weight liquid crystal and (1) a high-molecular weight compound in separate phases, the substrates each having a surface comprising a material having a reactive group on the side in contact with the composite film, the reactive group being chemically bonded to the high-molecular weight compound (

Abstract: A phase separation liquid crystal polymer for displays, optical shutters and memories is disclosed, having on the side chains thereof at least one liquid crystal component and at least one non-liquid crystal component, said liquid crystal component and non-liquid crystal component being present in separate phases. The polymer has an increased degree of freedom in control of physical properties and exhibits improved resolving power, improved contrast, and improved rate of response.

Abstract: A novel photochromic compound and a polymer comprising the photochromic compound are disclosed. The novel photochromic compound of the present invention is a spirooxazine compound having an addition polymerizable organic functional group or a ring-opening polymerizable organic functional group therein.

Abstract: An optical modulation display device is disclosed, comprising a polymer matrix having dispersed therein a liquid crystal composition containing a photochromic compound as a constituting component, or comprising a photochromic polymer matrix having dispersed therein a liquid crystal composition. The display device provides a wide area and flexible display which can be driven without using a matrix addressing system.

Abstract: The present invention provides a medical material having an easily-slippery property and durability which the conventional technologies have never provided by fixing a hydrophilic polymer on the surface of a base material through strong covalent bondings and a method for preparation thereof.

Abstract: A novel photochromic compound and a polymer comprising the photochromic compound are disclosed. The novel photochromic compound of the present invention is a spirooxazine compound having an addition polymerizable organic functional group or a ring-opening polymerizable organic functional group therein.