Abstract: An optically active compound exhibiting high speed response properties when used as a component of liquid crystal materials used in a liquid crystal display mode utilizing ferroelectricity, and a liquid crystal composition containing the compound are provided, which compound is expressed by the formula ##STR1## wherein R.sup.1 represents alkyl, alkoxy or alkoxycarbonyl each of 2 to 18 C, R.sup.2 represents alkyl of 3 to 18 C or alkoxy of 1 to 18 C and A represents a member selected from a group of two directly bonded six-membered rings having a halogen atom, cyano group, methyl group or trifluoromethyl group attached thereonto and * represents an unsymmetric carbon atom.

Abstract: A liquid crystal compound suitable as a material for ferroelectric liquid crystal display elements and a liquid crystal composition containing the same are provided, which liquid crystal compound is an optically active-2,5-diphenylpyridine expressed by the formula (I) ##STR1## wherein one of R.sup.1 and R.sup.2 is 1-20C alkenyl, alkynyl, alkoxy, alkenyloxy or alkynyloxy and the other is an optically active group; and X and Y each independently represent H, halogen or CN and at least one of X and Y is H.

Abstract: Novel compounds characterized by increased spontaneous polarization values as one of the important specific features required for ferroelectric liquid crystal compositions, a liquid crystal composition containing the same, and an optical switching element utilizing the composition as a liquid crystal.

Abstract: A compound capable of shortening the response time of liquid crystal display elements and a composition containing the same are provided, which compound is expressed by the formula ##STR1## wherein R.sup.1 represents a linear or branched chain alkyl group or alkoxy group, each of 1C-18C; Ar represents ##STR2## wherein X represents H, halogen atom, cyano group or methyl; A represents --COO-- or --CH.sub.2 O--; R.sup.2 represents a C.sub.1 -C.sub.18 alkyl, A C.sub.2 -C.sub.18 alkanoyl, a C.sub.3 -C.sub.18 alkoxycarbonyl or a C.sub.4 -C.sub.18 2-alkoxypropanoyl; C having a symbol * attached thereonto represents asymmetric carbon atom; and when R.sup.

Abstract: An optically active substance which, when added as a component of ferroelectric liquid crystal compositions, is extremely small in the reduction of the resulting liquid crystal temperature region, and a liquid crystal composition containing the same are provided, which substance is an optically active-2-alkoxy-propyl ether expressed by the formula (I) ##STR1## wherein R.sup.1 represents a straight or branched chain alkyl, alkoxy, alkanoyl, alkanoyloxy or alkoxycarbonyl each of 1 to 18 C; R.sup.2 represents a linear or branched chain alkyl each of 1 to 15 C; --A-- represents a specified group constituted by two directly bonded, six-membered rings; and * indicates asymmetric carbon atom.

Abstract: An optically active compound having particularly a specific feature of increasing spontaneous polarization value as one of important specific features for ferroelectric liquid crystal compositions, and a ferroelectric liquid crystal composition containing the compound are provided, which compound is expressed by the formula ##STR1## wherein R.sup.1 represents a linear or branched chain alkyl, alkoxy, alkanoyl, alkoxycarbonyl or alkoxycarbonyloxy each of 1 -15C, H, halogen or -CN; R.sup.2 represents an optically active group having 2-20 skeletal atoms, ##STR2## wherein X represents H, halogen or -CN; l represents an integer of 1-10; m is 0 or 1; and * indicates asymmetric C.

Abstract: New fluoroalkoxydiphenyl pyrimidines which are organic compounds having optically active groups, liquid crystal compositions containing the said compounds and electro-optic elements using the said compositions are provided.The compounds have the following general formula: ##STR1## wherein R.sup.1 is an alkyl or alkoxy group having 1-20 carbon atoms, a halogen atom or a cyano group, R.sup.2 is a straight-chain or branched chain alkyl group having 1-15 carbon atoms, --A-- is a group of ##STR2## X and Y independently indicate a hydrogen atom, a halogen atom or a cyano group, and * indicates that its carbon atom is an asymmetric carbon atom.

Abstract: A liquid crystalline, optically active compound useful as a component of various liquid crystal compositions, a liquid crystal composition containing the same and a light switching element using the liquid crystal composition are provided, which liquid crystalline, optically active compound is expressed by the formula ##STR1## wherein R.sup.1 is 1-18C alkyl or alkoxy, R.sup.2 is 2-18C alkyl or 1-18C alkoxy, A is ##STR2## wherein X is halogen or CN, m is 0 to 12, and * indicates an asymmetric carbon atom.

Abstract: A liquid crystalline compound useful as a component of liquid crystal compositions for liquid crystal display elements, exhibiting ferroelectric liquid crystal phases over a broad temperature range including room temperature, and a liquid crystal composition containing the same are provided. The compound is a thioether compound of the formula ##STR1## wherein R.sup.1 is a 2-10C alkyl; R.sup.2 is methyl or ethyl; but the carbon number of R.sup.1 is always larger than that of R.sup.2 ; A is ##STR2## wherein X is H, halogen or CN; Y is a 1-18C alkyl or alkoxy; l is 1 or 2; and * indicates optically active carbon atom.

Abstract: An optically active liquid crystal compound having specific features suitable to a display mode utilizing ferroelectric chiral smectic phases and particularly having a large spontaneous polarization value, and a chiral liquid crystal composition containing the compound are provided, which compound is expressed by the formula ##STR1## wherein R.sup.1 represents an alkyl group of 2 to 18 carbon atoms; R.sup.2 represents an alkyl group or alkoxy group each of 1 to 20 carbon atoms, hydrogen atom, a halogen atom or cyano group; A represents --COO-- or --OCO--; B and C each represent a single bond, ##STR2## wherein X represents hydrogen atom, a halogen atom or cyano group; and l, m and n each represent 0 or 1.

Abstract: A novel smectic C liquid crystal compound useful as a component of ferroelectric liquid crystal materials capable of effecting high-speed response is provided, which compound is a smectic liquid crystalline 5-alkoxy-2-(4-alkylphenyl)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 of 7 to 20 carbon atoms.

Abstract: The present invention provides optically active compounds represented by the following general formula: ##STR1## liquid crystal compositions containing the compounds, and electro optical elements using the above compositions.The compounds of the present invention are optically active compounds having characteristics suited for a ferroelectric liquid crystal composition, especially having enough spontaneous polarization to realize quick response.

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: The optically active compounds of the formula: ##STR1## wherein R.sup.1 is an alkyl or an alkyloxy group having a carbon number of 1-18, R.sup.2 is an alkyl group having a carbon number of 1-18, and A is a biphenyl group or a biphenyl group having a halogen atom or a cyano group are provided.The optically active compounds are useful for liquid crystal elements, especially for components of ferroelectric liquid crystal mixtures inducing high value of spontaneous polarization.

Abstract: An optically active-2-methylbutyrate capable of imparting a spontaneous polarization value to achiral smectic compositions and also constituting ferroelectric liquid crystal compositions exhibiting a fast response at room temperature, and a liquid crystal composition containing the same, and further a light-switching element therefrom, are provided, which optically active-2-methylbutyrate is expressed by the formula ##STR1## wherein R represents a linear or branched alkyl group or alkoxy group, each of 1 to 18 carbon atoms; A represents ##STR2## wherein X represents any one of F, Cl, Br or cyano group; and * indicates an optically active carbon atom.

Abstract: A sealed contact device is formed by disposing a fixed electrode having a fixed contact in an air-tight space defined in a hermetical container in which an electrically insulating gas is sealed at a high pressure, a movable contact of a movable electrode is provided for contact opening and closing with the fixed contact, and means is provided with respect to the movable electrode for allowing it positively movable in the air-tight manner, whereby an optimum contact opening speed of the movable contact and at the same time a proper contact pressure are both obtainable.

Abstract: A novel liquid crystalline, halogen-containing heterocyclic compound having a characteristic that even when its S.sub.c * phase is supercooled, no other smectic phases appear, and a liquid crystal composition containing the same are provided, which compound is expressed by the formula ##STR1## wherein R.sub.1 and R.sub.2 each represent an alkyl group of 2 to 18 carbon atoms; X represents --N.dbd. or --CH.dbd.; Y represents F or Cl; n represents an integer of 0 to 10; and a symbol * represents an asymmetric carbon atom.

Abstract: Novel chiral smectic liquid crystalline ester compounds having a superior stability and exhibiting a high response rate when used in the form of display elements and chiral smectic mixtures containing at least one of these compounds are provided, which compounds are expressed by the formula ##STR1## wherein n is an integer of 2 to 16; l is 0, 1 or 2; m is 1 or 2 under the condition of l+m.gtoreq.2; X represents methylene group --CH.sub.2 -- or single bond when l is zero, methylene group --CH.sub.2 -- or ether linkage --O-- when l=1 or ether linkage --O-- when l=2; and Y represents R, OR, --COR, --OCOR, --OCOOR or --COOR wherein R throughout represents an alkyl group of 1 to 18 carbon atoms; and asterisk * shows an optically active carbon atom.

Abstract: The present invention provided optically active alcohols represented by the general formula: ##STR1## wherein R.sup.1 indicates an alkyl or alkyloxy group having a carbon number of 1-18, and A indicates a phenyl or a biphenyl group; or a phenyl or biphenyl group having a halogen atom or a cyano group. The alcohols are intermediates of optically active materials useful for components of liquid crystal materials for liquid crystal display elements having quick response.

Abstract: A novel 3-substituted biphenyl compound useful as a component of chiral liquid crystal compositions useful for light-switching elements by the use of ferroelectric liquid crystals; a chiral liquid crystal composition containing the compound; and a light-switching element utilizing the composition are provided, which compound is expressed by the formula ##STR1## wherein either one of R.sup.1 or R.sup.2 represents an alkyl group of 4 to 18 carbon atoms having a methyl branch and the other thereof represents an alkyl group of 2 to 18 carbon atoms; X represents a halogen atom of F, Cl or Br or cyano group; and l represents 0 to 1.