Abstract: A novel liquid crystalline compound by the formula:

Abstract: Provided is a main chain type liquid crystal polyester which comprises at least two units selected from an aromatic diol unit, an aromatic dicarboxylic acid unit, and an aromatic hydroxycarboxylic acid unit as essential units and a structural unit having a cationically polymerizable unit in at least one of the terminal ends. The main chain type liquid crystalline polyester, when used as an optical material, is excellent in the capability of retaining a liquid crystal orientation having been aligned and fixed under practical service conditions and exhibits an excellent mechanical strength.

Abstract: A film for optical elements is formed by a liquid crystalline composition comprising the following components (a) and (b): (a) a liquid crystalline polymer which exhibits an optically positive uniaxial property; and (b) a polycyclic compound having a molecular weight of not more than 1,000 and wherein a plurality of alicyclic rings and/or aromatic rings are connected together through a linkage chain of 0 to 4 main-chain carbon atoms bonded to different ring carbon atoms, with hydrocarbon groups each having 1 to 20 carbon atoms being bonded respectively to both end rings through a linkage chain of 0 to 4 main-chain carbon atoms, an orientation form formed in the state of liquid crystal of said liquid crystalline composition being fixed.

Abstract: As a compensator for use in an OCB mode liquid crystal display there is provided a compensating film capable of making color compensation and attaining such a viewing angle expansion as has not been attainable heretofore. A compensating film for a liquid crystal display, constituted by at least one layer of a compensating film to be used in an OCB mode liquid crystal display, the compensating film being formed by a discotic liquid crystalline material having a fixed orientation form of a discotic liquid crystal, the compensating film being disposed between a driving liquid crystal cell and a pair of upper and lower polarizing plates, and the orientation form being a hybrid orientation in which the angle between discotic liquid crystal directors near the upper interface of the film and the film plane and the angle between discotic liquid crystal directors near the lower interface of the film and film plane are different from each other.

Abstract: Provided is a liquid crystal display device of a TN type which is improved on a display contrast, gray scale characteristics and viewing angle characteristics of a display color. A liquid crystal cell of a TN type for drive is sandwiched by a pair of upper and lower polarizing plates and at least one compensating film which has an extinction axis angle of 5 to 90 degrees as an absolute value and an optical rotating angle of 0.

Abstract: As a compensator for use in an OCB mode liquid crystal display there is provided a compensating film capable of making color compensation and attaining such a viewing angle expansion as has not been attainable heretofore.A compensating film for a liquid crystal display, constituted by at least one layer of a compensating film to be used in an OCB mode liquid crystal display, the compensating film being formed by a discotic liquid crystalline material having a fixed orientation form of a discotic liquid crystal, the compensating film being disposed between a driving liquid crystal cell and a pair of upper and lower polarizing plates, and the orientation form being a hybrid orientation in which the angle between discotic liquid crystal directors near the upper interface of the film and the film plane and the angle between discotic liquid crystal directors near the lower interface of the film and film plane are different from each other.

Abstract: A compensating film capable of compensating both twist structure based on a liquid crystal cell and refractive index anisotropy to diminish the visual angle dependence of a liquid crystal display is provided.The film is formed using a discotic liquid crystalline material and the orientation form of the discotic liquid crystal is a twisted orientation.

Abstract: A liquid crystalline polymer film useful as a high functional optical element is provided. Said liquid crystalline polymer film is formed on a substrate and having at least a tilt orientation fixed, and said tilt orientation is such that the angle between a director of said liquid crystalline polymer and a flat surface of said substrate is in the range of 5 to 85 degrees in terms of an average value.

Abstract: A viewing angle compensator for a liquid crystal display having characteristics such as being able to diminish the visual angle dependency of the liquid crystal display is provided. The viewing angle compensator of the present invention comprises a light transmitting base and a film of a liquid crystalline polymer formed on the base, the liquid crystalline polymer taking in the state of liquid crystal a structure wherein a refractive index in the thickness direction is larger than a refractive index in any direction within the plane of the polymer and assuming a glassy state at a temperature lower than the liquid crystal transition point thereof.

Abstract: The present invention relates to a method for producing a viewing angle compensator for liquid crystal displays which diminishes the view angle dependency of the liquid crystal display. More specifically, the method of making the view angle compensator involves applying a coating of an optically active polyester containing as a constituent a hydrocarbon unit selected from the group consisting of bulky aromatic units, polycyclic hydrocarbon units and ortho-substituted aromatic units, or a composition containing a liquid crystalline polyester which contains the said hydrocarbon unit as a constituent and also contains an optically active compound to a light transmitting substrate. The foregoing coating is heat-treated at a temperature higher than the glass transition point of the polyester to form a cholesteric orientation. The heat-treated coating is thereafter cooled to a temperature lower than the glass transition temperature to solidify a cholesteric structure.

Abstract: A liquid crystalline polymer film useful as a high functional optical element is provided. Said liquid crystalline polymer film is formed on a substrate and having at least a tilt orientation fixed, and said tilt orientation is such that the angle between a director of said liquid crystalline polymer and a flat surface of said substrate is in the range of 5 to 85 degrees in terms of an average value.

Abstract: According to the present invention there is provided a viewing angle compensator for a liquid crystal display capable of diminishing the viewing angle dependency of the liquid crystal display.The viewing angle compensator comprises a light transmitting substrate and a film of a specific liquid crystalline polyester, the liquid crystalline polyester taking in the state of liquid crystal a structure wherein a refractive index in the thickness direction is larger than a refractive index at least in one direction in a plane and assuming a glassy state at a temperature lower than the liquid crystal transition point of the polymer.The viewing angle dependency of the liquid crystal display can be greatly diminished and thus the viewing angle compensator of the present invention contributes to the realization of high-grade displays and higher performance of a liquid crystal display unit.

Abstract: It is intended to provide a liquid crystalline polyester whose orientation in the state of liquid crystal can be easily immobilized as glass phase and which is suitable for application to optical elements.A liquid crystalline polyester comprising repeating units a, b, c and d represented by the following general formulae: ##STR1## where X and Y are each independently a hydrogen atom, Cl, Br or an alkyl group having 1 to 4 carbon atoms, the repeating units a, b, c and d being in mole ratios such that (a+b)/(c+d) is approximately 1, a/b is in the range from 98/2 to 50/50 and c/d is in the range from 70/30 to 10/90.

Abstract: It is intended to provide a novel polyester which is optically active, can be prepared easily and inexpensively and is superior in stability and solubility in solvents.A liquid crystalline polyester consisting essentially of repeating units represented by the following formulae (a), (b), or (b') and (c): ##STR1## where the repeating unit c contains an optically active carbon and X is an alkyl group having 1 to 4 carbon atoms or a halogen atom, the repeating units a, b or b' and c being in mole ratios such that a/b is in the range from 95/5 to 5/95, a/b' is range from 95/5 to 50/50 and (a+b)/c or (a+b')/c is approximately 1.