Abstract: A liquid-crystalline polymer composition comprising a ferroelectric liquid-crystalline polymer and a low molecular weight liquid-crystalline compound which exhibits smectic C phase or chiral smectic C phase. Such liquid-crystalline polymer compositions have not only excellent moldabilities such as ease of orientation, but also exhibit chiral smectic C phase at wide temperature range within room temperatures and exhibit high speed response to changes of external fields and high contrast ratios when they are used for optical display elements.

Abstract: There is disclosed a mesomorphic compound represented by the following formula (I): ##STR1## wherein A.sub.1 denotes a single bond, ##STR2## denotes ##STR3## X denotes hydrogen, a halogen or cyano group; Y denotes oxygen or sulfur; R.sub.1 and R.sub.2 respectively denotes a linear or branched alkyl, alkoxy, alkylcarbonyloxy, alkoxycarbonyl or alkoxycarbonyloxy group each having 1-18 carbon atoms and each capable of having a substituted of chloro, bromo, cyano, alkoxy or akoxycarbonyl group; and B denotes ##STR4## A ferroelectric liquid crystal composition comprises at least two mesomorphic compounds including at least one mesomorphic compound represented by the formula (I). A ferroelectric liquid crystal device is constituted by disposing the ferroelectric liquid crystal composition between a pair of substrates.

Abstract: A trifluorobenzene derivative having a superior stability and a large positive dielectric anisotropy value and a liquid crystal composition containing the derivative are provided, which derivative is expressed by the formula ##STR1## wherein R is 1-10C alkyl and one --CH.sub.2 -- group or two not-adjacent --CH.sub.2 -- groups in the alkyl may be replaced by O and/or --CO-- and/or --COO-- and/or --CH.dbd.CH--, --A-- and --B-- are 1,4-cyclohexylene, 1,4-phenylene, pyrimidine-2,5-diyl or 1,3-dioxane-2,5-diyl, l and m each are 0, 1 or 2 and l+m.gtoreq.1, and Z.sup.1 and Z.sup.2 each are --COO--, --OCO--, --CH.sub.2 CH.sub.2 --, --OCH.sub.2 --, --CH.sub.2 O--, --CH.dbd.CH-- or single bond and may be same or different.

Abstract: The invention relates to a liquid crystal display element with a particularly low temperature-dependence of the threshold voltage.

Abstract: A liquid crystal composition, comprising: a first liquid crystal material comprising 20 to 70% by weight, based on the total weight of the composition, of at least one liquid crystal compound of the formula: ##STR1## wherein each of R.sup.1 and R.sup.2 is independently an alkyl group having 1 to 8 carbon atoms.a second liquid crystal material comprising at least two kinds of liquid crystal compounds selected from compounds of the formulas: ##STR2## wherein R is independently an alkyl group having 1 to 8 carbon atoms, the amounts of compounds (VII), (VIII) and (IX), based on the total weight of the composition, being up to 20% by weight, up to 20% by weight, and up to 10% by weight, respectively, anda third liquid crystal material comprising 2 to 15% by weight, based on the total weight of the composition, of one kind of liquid crystal compound selected from compounds of the formulas: ##STR3## wherein each of R.sup.1 and R.sup.2 is independently an alkyl group having 1 to 8 carbon atoms.

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 device for reversible optical information storage with a polymeric liquid crystalline storage medium, with the storage medium consisting of a macroscopically oriented film of a liquid crystalline polymer that contains photochromic groups, and with the information being stored by local disorientation of the molecules induced by photoisomerization by means of a selectively acting light source.

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: The present invention provides a liquid crystal composition wherein properties required in the super twist birefringence effect mode (SBE mode), particularly the high transparent point, low viscosity, and controllable optical isotropic value (.DELTA.n) are kept well balanced, the steepness of the voltage-transmission property is improved, and the value of N.sub.max that indicates high multiplex properties is high.A liquid crystal composition is provided containing a first component represented by the general formula: ##STR1## wherein R.sup.1 and R.sup.2 each represent an alkyl group having 1 to 8 carbon atoms,and a second component represented by the general formula: ##STR2## wherein R.sup.3 represents an alkyl group having 1 to 8 carbon atoms, or an alkenyl group having 2 to 8 carbon atoms, R.sup.4 represents H or F, R.sup.5 represents a CN-group or F, and ##STR3## represents ##STR4## and a liquid crystal display device that uses the same.

Abstract: Variable-transmittance articles, such as an ophthalmic lens, are prepared by applying to or incorporating within the article a combination of two (or more) organic photochromic substances exhibiting different activated absorption maxima within the matrix in which the substances are incorporated. One organic photochromic substance has an absorption maximum within the range of between greater than 590 and about 700 nanometers. The other organic photochromic substance exhibits at least one absorption maximum and preferably two absorption maxima, within the range of between about 400 and less than 590 nanometers. The organic photochromic substances are used in a proportion to achieve a near neutral coloring of the article. The article may also be tinted with a light compatible tint (dye) to achieve a more neutral color when the photochromic substances are activated.

Abstract: Optically responsive films comprising birefringent nematic and/or birefringent chiral nematic liquid crystal microdroplets dispersed in electron beam cured polymeric reaction products are disclosed.

Abstract: A photochromic material adapted for coating light transmissive materials. The photochromic material contains photosensitive silver halide crystals having dimensions in the range of approximately 50 Angstroms to 800 Angstroms. The silver halide crystals are surface doped with copper ions and another sensitizer selected from mild reducing agents or sulfur-bearing ions. The crystals are dispersed in a protective polymer that does not irreversibly bind halogen.

Abstract: Certain derivatives of stilbene and diphenylacetylene are capable of second harmonic generation when illuminated by coherent optical radiation.

Abstract: Disclosed are herein optically active ether derivatives represented by the formula (I): ##STR1## (wherein X represents --COO-- or --OCO--; A represents an alkyl or alkoxyl group having 3 to 15 carbon atoms; R represents an alkyl or alkyloxyalkyl group having 1 to 20 carbon atoms; l and m each represents a number of 1 to 2; and * indicates an asymmetric carbon atom), preparation processes therefor, liquid crystal materials containing such ether derivatives as active ingredient, and an optical switching element using said liquid crystal materials as liquid crystal element.

Abstract: A liquid crystal display device of the type in which thermo-writing is performed by means of irradiation of laser beams, the display device including a laser-sensitive liquid crystal composition exhibiting a maximum absorption at or near the wavelength of the impinging laser beam with which the display device is to be used. The specific improvement of the present invention comprises including in the liquid crystal composition at least two types of laser-responsive dyes, each being present in an amount less than its solubility limit in the liquid crystal composition, and each of the dyes evidencing a maximum absorption at or near the wavelength of the laser beam. In an embodiment, the dyes are chosen from the class of squarilium dyes.

Abstract: Compounds of the formula ##STR1## wherein Z represents a single covalent bond or --CH.sub.2 CH.sub.2 --, R.sup.1 denotes 1E-alkenyl with 2-10 carbon atoms or 3E-alkenyl with 4-10 carbon atoms and R.sup.2 is alkyl with 1-10 carbon atoms, 2E-alkenyl with 3-10 carbon atoms or 3-alkenyl with 4-10 carbon atoms,as well as their use in liquid crystalline mixtures and for electro-optical purposes.

Abstract: An optically active ester compound useful as a component of a ferroelectric liquid crystal composition is represented by the following formula: ##STR1## wherein R is C.sub.1-18 alkyl or C.sub.1-18 alkoxyl; R' is C.sub.1-18 alkyl or C.sub.

Abstract: A nonlinear optical material is provided by mixing a polymer liquid crystal having a chiral center and a nonlinear optical compound. The polymer liquid crystal may be a ferroelectric polymer liquid crystal. The nonlinear optical material is preferably in the form of a solid solution. A nonlinear optical device is formed by orienting the nonlinear optical material to provide an optical member.

Abstract: A composite material includes droplets of a liquid crystal material dispersed within a matrix of a photopolymerized polymer. The material is prepared by forming a solution of the liquid crystal material and a monomer, and then polymerizing the monomer with light. The solubility of the liquid crystal material in the polymer is less than in the monomer. As polymerization progresses, a portion of the liquid crystal material separates as a second phase in the polymer matrix. The liquid crystal can be any suitable such material that is soluble in the monomer and less so in the polymer, and the monomer is a polymerizable acrylate or methacrylate. Liquid crystal devices are prepared by forming the composite material between two electrically conducting substrates.

Abstract: Spirooxazine compounds are incorporated into a plastic host comprised of copolymers of poly(vinyl alcohol) and poly(vinyl acetate). This combination results in a photochromic composite which exhibits significantly improved temperature stability relative to the prior art.