Abstract: The compound (1) according to the invention has general solid-state properties necessary for a compound, stability against heat, light and the like, a suitable optical anisotropy, a suitable dielectric anisotropy, and excellent compatibility with other liquid crystalline compounds. The liquid crystal composition according to the invention contains at least one compound represented by formula (1). The liquid crystal display element according to the invention contains the composition. The compound (1) is represented by formula (1): wherein Ra, Rb, A1, A2, A3, A4, A5, A6, Z11, Z12, Z13, Z14, Z15, Z16, Y1, Y2, k, l, m, n, p and q are as defined in the specification.

Abstract: The compound (1) according to the invention has general solid-state properties necessary for a compound, stability against heat, light and the like, a suitable optical anisotropy, a suitable dielectric anisotropy, and excellent compatibility with other liquid crystalline compounds. The liquid crystal composition according to the invention contains at least one compound represented by formula (1). The liquid crystal display element according to the invention contains the composition. The compound (1) is represented by formula (1): wherein Ra, Rb, A1, A2, A3, A4, A5, A6, Z11, Z12, Z13, Z14, Z15, Z16, Y1, Y2, k, l, m, n, p and q are as defined in the specification.

Abstract: A novel liquid crystal material having a carbon chain containing a conjugated diene as a terminal substituent of the molecule and exhibiting superior characteristics is provided, which is a diene derivative expressed by the formula (I) ##STR1## wherein R and R' each independently represent 1-5C alkyl; A and B each independently represent 1,4-cyclohexylene or 1,4-phenylene; n is 0 or 1; m is an integer of 0 to 2; X and X' each independently represent H atom or F atom when A is 1,4-phenylene or represent H atom when A is 1,4-cyclohexylene; Y is alkyl, halogen or CN, alkoxy, methyl group substituted by 1-3 halogen atoms or trihaloalkoxy when A is 1,4-phenylene, or represent alkyl, alkoxy, methyl group substituted by 1-3 halogen atoms or trihaloalkoxy when A is 1,4-cyclohexylene; and R and R' are not simultaneously alkyl chain of 4 or more carbon atoms.

Abstract: A novel liquid crystal material having a carbon chain containing a conjugated diene as a terminal substituent of the molecule and exhibiting superior characteristics is provided, which is a diene derivative expressed by the formula (I) ##STR1## wherein R and R' each independently represent 1-5C alkyl; A and B each independently represent 1,4-cyclohexylene or 1,4-phenylene; n is 0 or 1; m is an integer of 0 to 2; X and X' each independently represent H atom or F atom when A is 1,4-phenylene or represent H atom when A is 1,4-cyclohexylene; Y is alkyl, halogen or CN, alkoxy, methyl group substituted by 1-3 halogen atoms or trihaloalkoxy when A is 1,4-phenylene, or represent alkyl, alkoxy, methyl group substituted by 1-3 halogen atoms or trihaloalkoxy when A is 1,4-cyclohexylene; and R and R' are not simultaneously alkyl chain of 4 or more carbon atoms.

Abstract: A novel liquid crystal material having a carbon chain containing a conjugated diene as a terminal substituent of the molecule and exhibiting superior characteristics is provided, which is a diene derivative expressed by the formula (I) ##STR1## wherein R and R' each independently represent 1-5C alkyl; A and B each independently represent 1,4-cyclohexylene or 1,4-phenylene; n is 0 or 1; m is an integer of 0 to 2; X and X' each independently represent H atom or F atom when A is 1,4-phenylene or represent H atom when A is 1,4-cyclohexylene; Y is alkyl, halogen or CN, alkoxy, methyl group substituted by 1-3 halogen atoms or trihaloalkoxy when A is 1,4-phenylene, or represent alkyl, alkoxy, methyl group substituted by 1-3 halogen atoms or trihaloalkoxy when A is 1,4-cyclohexylene; and R and R' are not simultaneously alkyl chain of 4 or more carbon atoms.

Abstract: A novel liquid crystal compound having an intermediate group of a cis-1,4-substituted 2-butenyl group, low viscosity and a broad mesomorphic temperature range is provided, which compound is expressed by the following formula: ##STR1## wherein R.sup.1 represents an alkyl group of 1 to 10 carbon atoms, n represents 1 or 2, X represents a hydrogen atom, an alkyl group, a halogen atom, a cyano group, an alkoxy group, a methyl group substituted by 1 to 3 halogen atom(s) or a trihaloalkoxy group, and Y and Y' each independently represents a hydrogen atom, or a halogen atom.

Abstract: A novel liquid crystal material having an alkenyl group at the end of the molecule, and having a low viscosity is provided. When the compound is added to a display element it is able to reduce the threshold voltage of the resulting display element. The compound is expressed by the formula (I), ##STR1## wherein X is a F atom, a trifluoromethyl group, a trifluoromethoxy group or a difluoromethoxy group, --A-- is 1,4-cyclohexylene or 1,4-phenylene, --B-- is 1,4-cyclohexylene, l is 0, 1 or 2, m is 0, 1 or 2, l+m.gtoreq.1, Z is --CH.sub.2 CH.sub.2 -- or single bond, n is an integer of 0 to 4, R is a H atom or a linear or branched alkyl group of 1-7C, and when R is an alkyl group, the double bond has a trans-configuration. The compounds of the present invention are suitable as liquid crystal material for STN display element, and further are chemically stable; hence it is possible to prepare a composition having a superior multiplex characteristic and capable of effecting a low voltage drive.

Abstract: The present invention provides a liquid crystalline compound having a large negative dielectric anisotropy value, a low viscosity and a large birefringence value and a liquid crystal composition suitable as an element constituting light switching elements. The liquid crystalline compound is expressed by the formula ##STR1## wherein R.sup.1 and R.sup.2 each independently represent an alkyl group or an alkoxy group each of 1 to 15 carbon atoms and Y.sub.1 and Y.sup.2 each independently represent H or F.

Abstract: A liquid crystal compound having a relatively low viscosity, a superior compatibility with other liquid crystalline compounds and suitable for preparing a liquid crystal device having a high response rate, and a superior liquid crystal composition containing the compound are provided, which compound is expressed by the formula ##STR1## wherein R.sup.1 is H, F, Cl, CN or 1-20C alkyl or alkenyl in which alkenyl one --CH.sub.2 -- group or two not adjacent --CH.sub.2 -- groups may be replaced by --O-- and in which alkenyl the position and number of the double bond may be optionally chosen; A.sup.1, A.sup.2 and A.sup.3 are ##STR2## the H atom(s) of which ##STR3## may be replaced by F, Cl or methyl; B.sup.1 and B.sup.2 are --CH.sub.2 CH.sub.2 --, --CH.sub.2 O--, --OCH.sub.2 -- or single bond; n is 0 or 1; and m is 0 to 20.

Abstract: An alkenyl ether derivative having a low viscosity, a good compatibility with other liquid crystalline compounds and being capable of use in preparing a liquid crystal display element having a high response rate are provided, which derivative is expressed by the formulaR.sub.1 --CH.sub.2 --O--(CH.sub.2)n--A.sub.1 --A.sub.2 A.sub.3 --R.sub.2[1]wherein R.sub.1 is a 2-7C alkenyl group having a double bond at its terminal or a double bond of a trans configuration at a position other than its terminal, R.sub.2 is 1-10C alkyl group or alkoxy group, A.sub.1 and A.sub.2 each independently are a 1,4-phenylene or a trans-1,4-cyclohexylene, A.sub.3 represents a 1,4-phenylene, a trans-1,4-cyclohexylene or a single bond and n is 1 or 2.

Abstract: The present invention provides a novel pyrimidine derivative having a large .DELTA..epsilon. value and a low viscosity, and affording a liquid crystal composition having a high clearing point and a low threshold voltage value without raising its viscosity when the derivative is mixed with other liquid crystal compositions or liquid crystal compound. The pyrimidine derivative is a 5-[2'-(trans-4"-alkylcyclohexyl)ethyl]-2-(3,4-difluorophenyl)pyrimidine expressed by the formula ##STR1## wherein R represents a linear alkyl group having 1 to 10 carbon atoms.

Abstract: A 2-substituted-alkyl ether having an optically active group and useful as a component of ferroelectric liquid crystal compositions and a liquid crystal composition containing the same are provided, which 2-substituted-alkyl ether is expressed by the formula ##STR1## wherein R.sup.1 represents a linear or branched chain alkyl, alkoxy, alkanoyl, alkanoyloxy or alkoxycarbonyl of 1 to 18 C; R.sup.2 represents a linear or branched alkyl of 2 to 15 C; ##STR2## each independently represents ##STR3## wherein Y represents cyano, halogen, methyl or methoxy; X represents --OR.sup.3, ##STR4## F, Cl or Br wherein R.sup.3 represents a linear or branched alkyl group of 1 to 10 C of H; and * indicates asymmetric C.

Abstract: An optically active compound particularly useful as a component of liquid crystal compositions having a high response rate and a chiral liquid crystal composition containing the same are provided, which optically active compound is expressed by the formula (I) ##STR1## wherein R.sup.1 represents alkyl or alkoxy each of 1-20 C, H, halogen or CN; ##STR2## and ##STR3## each represent a specified six-membered ring; R.sup.2 represents alkyl of 1-20 C; the asterisk designates an asymmetric carbon atom; and m and n each represents 0 or 1.

Abstract: An optically active compound having a large spontaneous polarization value and capable of affording a composition exhibiting a suitable ferroelectric liquid crystal temperature range and a liquid crystal composition containing the same are provided, which compound is expressed by the formula ##STR1## wherein either one of R.sup.1 and R.sup.2 represents an alkyl group or an alkoxy group each of 1 to 20 carbon atoms and another thereof represents an optically active group.

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: 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 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.