Abstract: A guest-host type liquid crystal composition comprising one or more host liquid crystals and dissolved therein one or more pleochroic dyes having a trans-4-substituted cyclohexyl group, preferably in an amount of 70% by mole or more of said trans-4-substituted cyclohexyl group among 4-substituted cyclohexyl groups, can afford a liquid crystal display device improved in display contrast and good stability due to no photochemical reaction of the liquid crystal composition.

Abstract: A ferroelectric liquid crystal device which comprises at least one pair of counterposed substrates, a ferroelectric liquid crystal material provided between the substrates, means for applying an electric field to the liquid crystal material and provided at the substrates, an alignment-controlling layer provided on the surface on the liquid crystal material side of each of the substrates, and a sealing member at the peripheral edges of the substrates, the alignment-controlling layer being a film of an organic polymer whose .beta. dispersion temperature is higher than the curing temperature of a sealant for the sealing member, preferably at least 200.degree. C., has a good alignment state of ferroelectric liquid crystal molecules achieved by cooling alone without any application of an electric field and has good display qualities such as a high contrast.

Abstract: Disclosed is an electrophotographic photoreceptor in which an organic lubricant is provided on the surface of an organic photoconductive layer or on a protective layer formed on the organic photoconductive layer. Elements of the organic lubricant are partly exposed from the surface of the organic photoconductive layer or the protective layer while the remainder portions of the elements are embedded or fixed by chemical reaction in the surface region of the photoconductive layer or the protective layer so that the exposed portions of the elements of the organic lubricant provides a lubricating surface layer. The lubricating surface layer supresses wear of the photoreceptor thereby enabling the photosensitive layer to withstand a long repeated use without impairing electrophotographic characteristics.

Abstract: In an optical data storage medium comprising a resin, substrate, a primary coat formed thereon and a recording layer of a dye decomposable by a laser beam formed on the primary coat, said primary coat is a silicone resin layer whose surface had been subjected to a plasma treatment. The primary coat prevents the substrate from attack by solvent for forming the recording layer, and enables the recording layer to be uniform in thickness with good adhesion.

Abstract: Disclosed are a novel naphthalocyanine dye shown in the specification, a method for preparing the same, and an optical information recording medium employing the same.According to the present invention, there can be obtained a novel naphthalocyanine dye, a method for preparing the same, and an optical information recording medium employing the same, which has excellent characteristics in recording/reading out property and in reading stability.

Abstract: A liquid crystal display element comprising a pair of substrates, a pair of electrodes provided on the respective substrates, at least one of which is transparent and a liquid crystal layer disposed between said substrates, the liquid crystal layer comprising a nematic liquid crystal, which exhibits a positive dielectric constant anisotropy and contains an optically active substance, the liquid crystal moleccule orientation direction in the liquid crystal layer is twisted in the range of 200.degree. to 250.degree. from the one substrate surface toward the other substrate surface so as to form a helical structure therein. A polyimide orientation film is provided between the electrodes and the liquid crystal layer. The polyimide orientation film is one made of a polyimide prepared by reacting a diamine compound having a long-chain hydrocarbon group or a diamine compound having a trifluoromethyl group with a tetracarboxylic dianhydride and causes a pretilt angle of at least 3.degree.

Abstract: The element comprises a pair of transparent substrates, a pair of light-transmitting electrodes each provided on the respective substrates, a ferroelectric liquid crystal layer disposed between the pair of substrates and orientation control films for the molecules of the ferroelectric liquid crystal provided between the electrodes and the ferroelectric liquid crystal layer. The orientation control film controls a tile angle of a biphenyle series nematic liquid crystal having biphenyl ring system below 1.5.degree. and causes a uniform molecule orientation characteristic and a memory property for the ferroelectric liquid crystal element of smectic C* liquid crystal and having a liquid crystal layer thickness of even more than 4 .mu.m.

Abstract: A liquid crystal composition containing azo dyes represented by the formula (I.sub.0) ##STR1## wherein X represents ##STR2## A.sup.1 represents --O-- or --NH--; R.sup.1 represents a hydrogen atom, an alkyl group, an alkoxyalkyl group, an aryloxyalkyl group, a dialkylaminoalkyl group, an arylaminoalkyl group, a cycloalkyl group, an alkoxy group, an alkoxyalkoxy group, an arylalkoxy group, an aryl group, a halogen atom or a group of ##STR3## D.sup.1 and D.sup.2 each represents an aromatic group which does not contain an ionic group;U.sup.1 and U.sup.2 each represents a hydrogen atom, a halogen atom, a methyl group, a methoxy group or an ethoxy group;Y.sup.1 represents --O-- or ##STR4## R represents a hydrogen atom, an alkyl group or may be connected to Z.sup.10 to Z.sup.12 to form a ring;Z.sup.4 to Z.sup.12 each represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxy group, an acylamino group or a cyano group, or Z.sup.4 and Z.sup.5, Z.sup.7 and Z.sup.8, and Z.sup.10 and Z.sup.

Abstract: In a liquid crystal display device produced by forming an orientation controlling film on each surface of upper and lower substrates having an electrode, placing a liquid crystal composition between said substrates, and then sealing the periphery of the substrate, the response times, particularly those at low temperatures can be reduced by using, as the aforesaid liquid crystal composition, a liquid crystal composition which is obtained by adding a material having a glass transition temperature (T.sub.g) of -90.degree. C. or lower to a liquid crystal material base and has a T.sub.g of -82.degree. C. or lower.

Abstract: A colorless liquid crystalline compound having at least one 6-membered ring and non-cyclic end groups in the molecular skeleton, said 6-membered ring containing two or more carbon atoms, at least one of which is directly bonded to a methylene group of a non-cyclic group having an alkoxy group at another end has a wide mesomorphic range. When said colorless liquid crystalline compound is mixed with a liquid crystal composition, the resulting mixture also has an enlarged mesomorphic range and in almost all cases has a reduced viscosity.

Abstract: A liquid crystal compound of the formula: R.sub.2 --X.sub.1 --Y.sub.1 --C(O)S--Y.sub.2 --Z, wherein R.sub.2 is preferably C.sub.7-14 alkyl; X.sub.1 is --COO-- or --OCO; ##STR1## and Z is --NO.sub.2 or --CN, shows a smectic phase, is large in positive delectric anisotropy and can give a liquid crystal composition suitable for use in a thermal address display device.

Abstract: The present liquid crystal compounds are novel ester-type compounds showing a smectic liquid crystal phase and being capable of increasing a dielectric constant anisotropy, represented by the following general formula: R--X.sub.1 --Y.sub.1 --X.sub.2 --Y.sub.2 --NO.sub.2, wherein R is an alkyl group; X.sub.1 and X.sub.2 are the same or different from each other and are group --COO-- and --OOC--, and when X.sub.1 is group --COO--, ##STR1## The present liquid composition contains the novel compound, and the present liquid crystal display device uses the liquid crystal composition for utilizing the characteristics of the novel compound. Particularly, the present liquid crystal display device is a thermally addressed display device.

Abstract: An optical apparatus comprises an optical device having an optically functional material sandwiched between a pair of substrates with electrodes formed on opposing surfaces. The optically functional material has such a characteristic that intensity of light issuing from the optical device changes asymmetrically in response to inversion of the polarity of an applied external field. Pulse voltages of one polarity for determining the intensity of the issuing light and pulse voltages of an opposite polarity are applied from a source at a predetermined period so that an average voltage is zeroed within the predetermied period. The issuing light intensity under the application of the pulse voltages of one polarity and the issuing light intensity under the application of the other pulse voltages are selected or changed by a switching unit.

Abstract: Orientation control films are coated on a pair of transparent substrates on the side contiguous to the ferroelectric liquid crystal layer and rubbed for aligning molecules thereof. The films are made of a polyimide polymer prepared by ring closure by heating and dehydrating of a polyamic acid which is synthesized by condensing, for example, pyromellitic dianhydride with 4,4'-diaminoterphenyl. A contrast ratio of the ferroelectric liquid crystal element is improved while keeping a high response characteristic of the ferroelectric liquid crystal materials.

Abstract: A liquid crystal composition comprising a host liquid crystal material and at least one guest novel anthraquine dye dissolved in said host liquid crystal material has a high order parameter, sufficient solubility in the host liquid crystal and high stability.

Abstract: A liquid crystal composition containing azo dyes represented by the formula (I.sub.0) ##STR1## wherein X represents ##STR2## A.sup.1 represents --O-- or --NH--, R.sup.1 represents a hydrogen atom, an alkyl group, an alkoxyalkyl group, an aryloxyalkyl group, a dialkylaminoalkyl group, an arylaminoalkyl group, a cycloalkyl group, an alkoxy group, an alkoxyalkoxy group, an arylalkoxy group, an aryl group, a halogen atom or a group of ##STR3## D.sup.1 and D.sup.2 each represents an aromatic group which does not contain an ionic group; U.sup.1 and U.sup.2 each represents a hydrogen atom, a halogen atom, a methyl group, a methoxy group or an ethoxy group;Y.sup.1 represents --O-- or ##STR4## R represents a hydrogen atom, an alkyl group or may be connected to Z.sup.10 to Z.sup.12 to form a ring;Z.sup.4 to Z.sup.12 each represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxy group, an acylamino group or a cyano group, or Z.sup.4 and Z.sup.5, Z.sup.7 and Z.sup.8, and Z.sup.10 and Z.sup.

Abstract: The description is concerned with a liquid crystal composition of the guest-host type which contains a pleochroic dye dissolved therein. The dye molecule has an end group or end groups in the molecule represented by the general formula: ##STR1## where Ro designates a straight chain of alkyl group, in which methylene group not adjacent to the nitrogen atom may be substituted by oxygen atom or sulfer atom; R1 designates an alkyl group having a chain length different from that of the alkyl group of Ro or a group ##STR2## in R1 a methylene group not adjacent to the nitrogen atom may be substituted by oxygen atom or sulfur atom, and R2 designates hydrogen atom, alkyl group, alkoxy group, cycloalkyl group or dialkylamino group.

Abstract: The liquid crystal compound of this invention is characterized by having the general formula.

Abstract: The present invention is characterized by a smectic liquid crystal compound represented by the following formula: ##STR1## wherein R is selected from alkyl and alkoxy groups; X from ##STR2## m and n are natural numbers; and R* is an optically active group containing an asymmetric carbon atom, and a liquid crystal composition containing said compound as a component. This compound is excellent in optical stability and high-speed response.

Abstract: A colorless liquid crystalline compound having at least one 6-membered ring and non-cyclic end groups in the molecular skelton, said 6-membered containing two or more carbon atoms, at least one of which is directly bonded to a methylene group of a non-cyclic group having an alkoxy group at another end has a wide mesomorphic range. When said colorless liquid crystalline compound is mixed with a liquid crystal composition, the resulting mixture also has an enlarge mesomorphic range and in almost all cases has a reduced viscosity.