Abstract: Carbocyclic compounds of the formula I ##STR1## wherein Q is a benzene or cyclohexane ring or a naphthalene system, X is in each case --CH.sub.2 --(CH.sub.2).sub.p -- where it is also possible for one or two non-adjacent CH.sub.2 groups to be replaced by --O--, --S--, --CO--, --O--CO--, --CO--O-- or --CH.dbd.CH--,p is 0, 1 or 2,A.sup.1 and A.sup.2 independently of one another are each a 1,4-phenylene group which is unsubstituted or monosubstituted or polysubstituted by halogen atoms and/or CH.sub.3 groups and/or CN groups and in which it would also be possible for one or more CH groups to be replaced by N atoms, a 1,4-cyclohexylene group wherein it would also be possible for one or two non-adjacent CH.sub.2 groups to be replaced by --O-- and/or --S--, a piperidine-1,4-diyl group or a 1,4-bicyclo[2.2.2]octylene group,Z is --CO--O--, --O--CO--, --O--, --CH.sub.2 --, --CH.sub.2 O--, --OCH.sub.2 --, --CH.sub.2 CH.sub.2 --, --CHCN--CH.sub.2 --, --CH.sub.2 --CHCN--, --CH.dbd.CH--, --CH.dbd.N--, --N.dbd.CH--, --NO.

Abstract: A liquid crystal optical element comprising a polymeric liquid crystal composition is disclosed, wherein the composition contains at least one compound selected from adamantane, an adamantane derivative, terphenyl, and a terphenyl derivative in an amount of from 0.01 to 15% by weight based on a polymeric liquid crystal. The optical element exhibits uniform vertical orientation.

Abstract: A non-linear optical article is constituted of a derivative of benzalacetophenone represented by the following general formula: ##STR1## wherein A and B each represent the same or different atom or group and stand for a hydrogen atom, an alkoxy group having 1 to 4 carbon atoms, a chlorine atom, a bromine atom, an amino group or a dialkylamino group having 1 to 2 carbon atoms.

Abstract: An optically active polymer comprises recurring units of the following formula: ##STR1## wherein l is an integer of 5-1000, n is an integer of 1-3, m is an integer of 2-20, and * denotes the location of an asymmetric center. The optically active polymer has a good mutual solubility with a low-molecular weight mesomorphic compound and is easily mixed with the latter to provide a uniform liquid crystal composition which shows ferroelectricity and better film formability and stability than the low-molecular weight mesamorphic compound alone.

Abstract: A phenyl pyrimidine compound of this invention represented by the following formula (I) forms a smectic C phase and is useful for a constituent of a ferroelectric liquid crystal composition.R.sub.1 --Ph--Py--R.sub.2 (I)wherein Ph represents 1,4-phenylene group, Py represents 2,5-pyrimidine, R.sub.1 and R.sub.2 represent independently an acyloxy group or alkoxy group, either R.sub.1 or R.sub.2 represents a linear acyloxy group or a linear alkoxy group having more than seven carbon atoms. The compound of this invention has a properties of .circle.1 a low viscosity, .circle.2 of forming a smectic C phase (Sc), .circle.3 of being more than 70.degree. C. of an upper limit temperature of a Sc phase. By applying these properties it is able to give a good alignment effect of a composition comprising the compound using a conventional alignment effect of a TN type cell.

Abstract: In one embodiment this invention provides a novel class of azomethine compounds which exhibit nonlinear optical response, such as 4-(4-dimethylaminobenzylideneamino)-4'- nitrostilbene: ##STR1##

Abstract: A ferroelectric liquid crystal composition exhibiting SC* phase within a broad temperature range including room temperature and also having high-speed response properties and a light switching element using the above-mentioned liquid crystal composition and exhibiting high-speed response properties are provided, which composition comprises at least one member of chiral compounds expressed by the formula ##STR1## wherein R.sup.1 and R.sup.2 each represent a linear or branched chain alkyl, alkoxy, alkoxyalkoxy, alkoxycarbonyl, alkanoyl or alkanoyloxy group each of 1 to 18 C and at least one of R.sup.1 and R.sup.2 has an asymmetric carbon atom in the alkyl chain moiety of these groups, and at least one member of chiral compounds having a spontaneous polarization value of 40 nC/cm.sup.2 or more.

Abstract: A composite material having droplets of a liquid crystal material in a matrix of a coploymer of a multifunctional acrylate, or a mixture of different multifunctional acrylates, and a multifunctional mercaptan is prepared by photopolymerization. The liquid crystal material is initially mixed with a multifunctional acrylate monomer, a multifunctional mercaptan, and a photoinitiator to form a solution. The solution is exposed to ultraviolet light, whereupon the multifunctional acrylate monomer and multifunctional mercaptan copolymerize in a step reaction, and the liquid crystal separates from the copolymer as droplets dispersed throughout the copolymer matrix. The resulting material is placed between transparent, electrically conducting plates to form an electro-optic display device.

Abstract: Liquid-crystalline phenylpyrimidinyl cyclohexanecarboxylates having a smectic phase, a process for their preparation, and their use in liquid-crystal mixtures The phenylpyrimidinyl trans-cyclohexanecarboxylates of the general formula ##STR1## form a smectic C phase besides a relatively broad nematic phase when R.sup.1 denotes an alkyl radical having 10 to 16 carbon atoms, in particular 11 to 16 carbon atoms, or an alkoxy radical having 8 to 14 carbon atoms, and R.sup.2 denotes an alkyl radical having 2 to 9 carbon atoms. They are therefore particularly suitable as components of liquid-crystalline mixtures having a smectic C phase since they induce a relatively broad nematic phase or extend a narrow nematic phase which is present and extend the temperature range of the smectic C phase to low temperatures, but in particular to high temperatures.

Abstract: An improved light modulating material for use in electro-optic and thermo-optic display devices is produced by forming a homogeneous solution comprising an acrylic resin containing active hydrogen groups, a liquid crystal material, a diisocyanate or epoxide, and a solvent. The homogeneous solution is preferably applied to a conductive substrate and the solvent is then evaporated, causing phase separation resulting in formation of a liquid crystal phase dispersed within a solid polymer matrix. Application of an electric field to the substrate causes the liquid crystal material to align, which in turn causes the coating to switch from substantially translucent to substantially transparent. If the electric field is removed the light modulating material again becomes substantially translucent. Switching times can be improved by incorporating a titanate or zirconate organometallic material into the light modulating material.

Abstract: The invention relates to a method of manufacturing permeable mineral membranes.The method of the invention is characterized in that a thin layer of gel of peptised hydroxide of at least aluminum is deposited on a permeable perous substrate and the resulting membrane is dried and fired at a temperature between 500.degree. and 1100.degree. C.The resulting membranes can be used for isotopic separation of gases or for filtration and ultrafiltration.

Abstract: The invention relates to the use of compounds of the formula IR.sup.1 --Q.sup.1 --A--(A.sup.2).sub.q --R.sup.2 Iwherein ##STR1## and R.sup.1, R.sup.2, Q.sup.1, Q.sup.2 and q have the meaning specified in claim 1, as components of smectic liquid-crystalline phases, and also smectic liquid-crystalline phases, in particular chiral tilted smectic phases containing compounds of formula I.

Abstract: Compounds are provided which comprise a fluorocarbon terminal portion and a chiral hydrocarbon terminal portion, said terminal portions being connected by a central core, said compounds having tilted smectic mesophases or having latent tilted smectic mesophases which develop when said compounds having said latent mesophases are in admixture with said compounds having tilted smectic mesophases or said compounds having latent tilted smectic mesophases.

Abstract: An optically liquid crystalline compound having an extremely large spontaneous polarization value and a chiral smectic liquid crystal composition containing the compound are provided, the compound being expressed by the formula ##STR1## wherein m represents an integer of 2 to 18; l represents an integer of 0 to 12; n represents 0 or 1; R represents an alkyl group or an alkoxy group each of 2 to 20 carbon atoms, a halogen atom or cyano group; and A and B each represent a single bond, ##STR2## wherein X represents hydrogen atom, a halogen atom or cyano group, and a chiral smectic liquid crystal composition containing at least one kind of the above compound.

Abstract: Liquid crystal phases containing components of the formulae I and III ##STR1## have an acceptable combination of threshold steepness, viewing angle and temperature dependence at a low threshold voltage.

Abstract: This invention provides a nonlinear optical medium which is a composite of a microporous inorganic oxide glass which contains an incorporated solution of a solvent and an organic component which exhibits nonlinear optical response.In one embodiment the solution incorporated in the microporous glass monolith is composed of dioxane and 4-N,N-dimethylamino-4'-nitrostilbene.

Abstract: Pyrimidine derivatives represented by the general formula: ##STR1## wherein R is a straight chain alkyl group having from 1 to 12 carbon atoms or an alkoxy group having from 1 to 12 carbon atoms. The pyrimidine derivatives are added to nematic liquid crystal compositions to reduce the threshold voltage of display devices by increasing the N.fwdarw.I transition temperature and the dielectric anisotropy.

Abstract: Nitrogen-containing heterocyclic compounds of the formula IR.sup.1 --A.sup.1 --Z.sup.1 --A.sup.2 [Z.sup.2 --A.sup.3 ].sub.n --R.sup.2whereinR.sup.1 and R.sup.2 in each case independently of one another are an alkyl group with 1-15 C atoms, it also being possible for one or two non-adjacent CH.sub.2 groups to be replaced by 0 atoms and/or --CO-- groups and/or --O--CO-- groups and/or --CO--O-- groups, and one of the radicals R.sup.1 and R.sup.2 is also H, F, Cl, Br or CN,is a 1,4-cyclohexylene group, it also being possible for one or two non-adjacent CH.sub.2 groups to be replaced by 0 atoms, a 1,4-bicyclo(2,2,2)-octylene group or a 1,3-dithiane-2,5-diyl group,Z.sup.1 and Z.sup.2 in each case independently of one another are --CO--O--, --O--CO--, --CH.sub.2 CH.sub.2 --, --OCH.sub.2 --, --CH.sub.2 O-- or a single bond,A.sup.2 and A.sup.3 in each case independently of one another are a 1,4-phenylene group, pyrimidine-2,5-diyl group, 1,4-cyclohexylene group, it also being possible for one or two non-adjacent CH.

Abstract: A ferroelectric liquid crystal composition exhibiting SC* phase within a broad temperature range including room temperature and yet having cholesteric phase and further high-speed response properties and a light switching element using the above composition and having high-speed response properties are provided, which composition comprises an achiral compound expressed by the formula ##STR1## wherein R.sup.1 and R.sup.2 each represent the same or different linear or branched chain alkyl group of 1 to 18 carbon atoms, in 20 to 70% by weight and having cholesteric phase; and which composition may further comprise at least one member of optically active compounds selected from four specified pyrimidine compounds.

Abstract: A smectic C liquid crystal mixture having a broad smectic C phase temperature range including room temperature, a ferroelectric smectic C liquid crystal mixture having a large spontaneous polarization, comprising the above smectic C mixture and at least one optically active compound, and a liquid crystal display element having an improved response time, containing the above ferroelectric smectic C liquid crystal mixture are provided, which smectic C liquid crystal mixture comprises(1) at least two components at least one of which is a pyrimidine compound expressed by the formula ##STR1## wherein R.sup.1 represents a linear alkyl group of 4 to 20 carbon atoms and R.sup.2 represents a linear alkyl group having 7-20 carbons and having a smectic C phase;(2) at least one pyrimidine compound of the formula (I) and at least one pyrimidine compound expressed by the formula ##STR2## wherein R.sup.3 represents a linear alkyl group of 6 to 12 carbon atoms and R.sup.