Abstract: A liquid crystal composition is disclosed which comprises at least one liquid crystalline compound having a total number of carbon of 4 to 24 in the portions of acyclic hydrocarbon, and the average value of the total number of carbon atoms in the liquid crystalline compound in the liquid crystal composition is 5 or more. A liquid crystal display (particularly, AM-LCD) having higher voltage holding ratio than that of conventional ones can be achieved.

Abstract: A tolan derivative useful as a component of liquid crystal materials and being superior to conventional tolan derivatives in the characteristics of .DELTA.n and viscosity, and a liquid crystal composition containing the same are provided, which tolan derivative is expressed by the formula ##STR1## wherein R.sup.1 and R.sup.2 each represent an alkyl group of 1 to 10 carbon atoms.

Abstract: A compound and a liquid crystal composition containing the compound are provided, which compound, when added to a nematic liquid crystal composition, increases the dielectric anisotropy value, lowers its threshold voltage and raises the ratios of elastic constants and hence makes steep the voltage-transmittance characteristic,which compound is an alkenyl ether compound expressed by the formula ##STR1## wherein R is a 2-8C alkyl group having a double bond at its end or a double bond of trans configuration at an optional position and n is 0 to 4.

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: A liquid crystal compound is provided, having a large optical anisotropy .DELTA.n value and yet a low viscosity, and which can be added to a liquid crystal composition, without lowering the NI point of the composition and raising the viscosity thereof, while raising the .DELTA.n value thereof. The liquid crystal compound is a 4-substituted-4'-(1-alkynyl)tolan expressed by the formula ##STR1## wherein R.sup.1 and R.sup.2 each is 1-8C alkyl and one CH.sub.2 group or two non-adjacent CH.sub.2 groups present therein may be replaced by any one of O, --CO--, --CO--O--, --O--CO-- or --CH.sub.2 .dbd.CH.sub.2 --; --A-- is unsubstituted 1,4-phenylene, 1,4-phenylene having one or two F, Cl or Br atoms or CN groups, 1,4-cyclohexylene, pyrimidine-2,5-diyl or 1,3-dioxane-2,5-diyl; X is --COO--, --OCO--, --CH.sub.2 --CH.sub.2 --, --OCH.sub.2 --, --CH.sub.2 O--, --CH.dbd.CH-- or a single bond; n is 0 or 1 and when n is 0, X is a single bond; and Y is H or F.

Abstract: A novel phenylpyrimidinecarboxylate derivative which, when used as a component of liquid crystal compositions, can raise the clearing point of the mesomorphic range of the liquid crystal compositions and/or increase the dielectric anisotropy value of the compositions, and a liquid crystal compositions containing the derivative are provided, which derivative is expressed by the formula ##STR1## wherein X.sup.1 represents an alkyl or alkoxy each of 1-10 C; X.sup.2 represents a 4-substituted phenylk having an alkyl, of 1-10 C, F, Cl, Br or --CN at 4-position or a 3,4-disubstituted phenyl having F, Cl, Br or Cn at 4-position and F, Cl or Br at 3-position; and L represents a N atom and M represents a C atom.

Abstract: A benzoic acid derivative having a large positive dielectric anisotropy value and a superior compatibility, reducing the threshold voltage value of the resulting liquid crystal cell and being very effective for broadening the mesomorphic range of the resulting liquid crystal composiiton and reducing the driving voltage, and a liquid crystal composition containing the derivative are provided, which benzoic acid derivative is expressed by the formula ##STR1## wherein R represents an alkyl group of 1 to 10 carbon atoms and A represents ##STR2##

Abstract: A liquid crystalline compound having a small .DELTA.n value; suitable for preparing a liquid crystal display element having a broad viewing angle; having a large positive .DELTA..epsilon. value; and suitable for preparing a liquid crystal composition having a low driving voltage for liquid crystal display devices, and a liquid crystal composition containing the compound are provided, which compound is expressed by the formula ##STR1## wherein n represents an integer of 0 to 20.

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: 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: A liquid crystalline compound useful as a component of liquid crystal compositions for TN mode display elements and having a large positive .DELTA..epsilon. value and also a low viscosity for the .DELTA..epsilon. value and a liquid crystal composition containing the compound are provided, which compound is expressed by the formula ##STR1## wherein n represents an integer of 0 to 20.

Abstract: A liquid crystalline compound and a liquid crystal composition containing the compound usable for liquid crystal display devices are provided, which liquid crystalline compound is expressed by the formulaR.sup.1 --A.sup.1 --B.sup.1 --A.sup.2 --B.sup.2 --A.sup.3.sub.n (CH.sub.2).sub.m CH.dbd.CF.sub.2wherein R.sup.1 is H or 1-20C alkyl or alkenyl wherein one --CH.sub.2 --group or two --CH.sub.2 -- groups not adjacent to each other may be substituted by --O--; the position and number of the double bond may be optionally chosen; A.sup.1, A.sup.2 and A.sup.3 each are ##STR1## and the H of the ##STR2## may be substituted by F, Cl or methyl; B.sup.1 and B.sup.2 each are --CH.sub.2 CH.sub.2 --, --CH.sub.2 O--, --OCH.sub.2 -- or a single bond; n is 0 or 1; and m is 0-20.

Abstract: A novel phenylprimidinecarboxylate derivative which, when used as a component of liquid crystal compositions, can raise the clearing point of the mesomorphic range of the liquid crystal compositions and/or increase the dielectric anisotrophy value of the compositions, and a liquid crystal compositions containing the derivative are provided, which derivative is expressed by the formula ##STR1## wherein X.sup.1 represents an alkyl or alkoxy each of 1-10 C; X.sup.2 represents a 4-substituted phenyl having an alkyl, of 1-10 C, F, Cl, Br or --CN at 4-position or a 3,4-disubstituted phenyl having f, Cl, Br or CN at 4-position and F, Cl or Br at 3-position; and either one of L or M represents .dbd.N-- and the other represents --C.dbd..

Abstract: Novel compounds which, when used as a component of nematic liquid crystal compositions, can improve the characteristics of .DELTA.n and viscosity of the resulting liquid crystal compositions and also does not greatly adversely affect other characteristics thereof, and a liquid crystal composition containing such a compound are provided, which compound is expressed by the formula ##STR1## wherein R.sub.1 and R.sub.2 each independently represent an alkyl group of 1 to 12 carbon atoms.

Abstract: A novel compound which is able to improve various characteristics of display element by using it as a component for liquid crystal compositions, and a liquid crystal composition containing the same are provided, which compound isa 2-pyrimidinyl-1, 3-dioxane compound expressed by the formula ##STR1## wherein Y.sub.1 represents --R, ##STR2## SCH.sub.3 or --CN; Y.sub.2, --R, ##STR3## R, an alkyl group of 1-12 C and one or two CH.sub.2 groups therein can be replaced by oxygen atom; X.sub.1, X.sub.2, X.sub.3 and X.sub.4 each independently are choiced from H, F, Cl, Br or --CN; and X.sub.5, F, Cl, Br, --CN or an alkyl group of 1-12 C and one or two CH.sub.2 groups therein can be replaced by oxygen atom.

Abstract: Novel compounds which, when used as a components of liquid crystal compositions, have good compatibility with other components and also have large values of dielectric anisotropy and optical anisotropy, and liquid crystal compositions containing the same are provided, which compounds are 4'-cyano-3'-halogenophenyl 4-(5-substituted-pyrimidin-2-yl)benzoate expressed by the formula ##STR1## wherein R represents an alkyl group of 1 to 10 carbon atoms or --(CH.sub.2).sub.m --O--(CH.sub.2).sub.p --CH.sub.3 wherein m and p each represent an integer of 0 to 8 and m+p.ltoreq.8, and X represents a halogen atom.

Abstract: A novel pyrimidine derivative which, when used as a component of a liquid crystal composition, is useful for driving a liquid crystal cell containing the composition at low voltages, and a liquid crystal composition containing the same are provided, which pyrimidine derivative is expressed by the formula ##STR1## wherein n represents an integer of 0 or 1; R represents an alkyl or alkoxy group of 1 to 10 carbon atoms; and X.sub.1, X.sub.2 and X.sub.3 each represent hydrogen atom, F, Cl or Br as halogeno group, cyano group or trifluoromethyl group and at least one of X.sub.1, X.sub.2 and X.sub.3 is trifluoromethyl group.

Abstract: A compound which, when added as a component to other components, raises the N-I point of the resulting liquid crystal composition and nevertheless affords only a relatively small rise in viscosity of the composition, and a liquid crystal composition containing the same are provided, which compound is a 1-(trans-4'-alkylcyclohexyl)-2-4"-[trans-4"'-(trans-4""-alkylcyclohexyl)cy clohexylphenyl]ethane expressed by the formula ##STR1## wherein R.sup.1 and R.sup.2 each represent an alkyl group of 1 to 10 carbon atoms.

Abstract: A novel liquid crystal compound useful as a component of liquid crystal compositions and a liquid crystal composition containing the same are provided, which compound is a phenoxypropanol ester derivative expressed by the formula ##STR1## wherein R.sup.1 and R.sup.2 each represent an alkyl group or an alkoxy group each of 1 to 15 carbon atoms, F atom, Cl atom or CN group, but either one of R.sup.1 and R.sup.

Abstract: A novel liquid crystal compound which is superior in compatibility with other liquid crystal compounds or liquid crystal compositions, chemically stable, and when added to liquid crystal compositions, can raise the clearing point thereof almost without increasing the viscosity and enhance .DELTA..epsilon. and .DELTA.n thereof, and a liquid crystal composition containing the same are provided, which compound is expressed by the formula ##STR1## wherein R represents an alkyl group or an alkoxy group each of 1 to 10 carbon atoms; Y represents F, Cl or H; and Z represents F, Cl, cyano group or an alkyl group or an alkoxy group each of 1 to 10 carbon atoms.