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.

Abstract: A novel organic compound usable as a component of liquid crystal compositions having a positive value of dielectric anisotropy and a liquid crystal composition usable as a material for liquid-crystalline display devices operated under a low driving voltage are provided which compound is a benzoic acid ester derivative expressed by the formula ##STR1## wherein R represents an alkyl group of 1 to 10 carbons and X represents ##STR2##

Abstract: A novel ester derivative affording a positive large dielectric anisotropy value (.DELTA..epsilon.) of liquid crystal compositions and also reducing the optical anisotropy value (.DELTA.n) thereof when the derivative is contained therein, and a liquid crystal composition containing the ester derivative are provided, which ester derivative is expressed by the formula ##STR1## wherein R represents an alkyl group or an alkoxy group each of 1 to 10 carbon atoms and X represents F or Cl.

Abstract: Novel liquid crystal compounds, 2-cyano-4-halogenophenyl substituted-benzoates suitable as a component constituting a liquid crystal composition which exhibits a negative dielectric anisotropy, and a liquid crystal composition containing the same are provided, which benzoates are expressed by the formula ##STR1## wherein R represents an alkyl group or an alkoxy group each of 1 to 10 carbon atoms; ##STR2## represents ##STR3## or ##STR4## X and Y each represents H or a halogen atom of F or Cl and at least one of X and Y is necessarily H; and Z represents a halogen atom of F, Cl or Br.

Abstract: A novel compound usable as a component constituting liquid crystal materials having a positive dielectric anisotropy value and a liquid crystal composition containing the same are provided, which compound is an alcohol derivative expressed by the general formula ##STR1## wherein R.sup.1 represents a hydroxyalkyl group of 1 to 10 carbon atoms having hydroxyl group at the end or an intermediate position thereof; R.sup.2 represents an alkyl group or an alkoxy group each of 1 to 10 carbon atoms or --C.tbd.N; and ##STR2## represents ##STR3## and when R.sup.2 represents --C.tbd.

Abstract: A novel pyridine derivative capable of increasing the dielectric anisotropy value (.DELTA..epsilon.) or optical anisotropy value (.DELTA.n) of liquid crystal compositions including the derivative and lowering the driving voltages of liquid crystal display elements using the composition, and also a liquid crystal composition containing the pyridine derivative are provided, which pyridine derivative is expressed by the formulaR--X--COO--Y--CH.sub.2 CH.sub.2 --Z--Awherein R represents an alkyl group or an alkoxy group each of 1-10 carbon atoms; X represents ##STR1## Y represents ##STR2## when Y is ##STR3## Z represents ##STR4## and A represents F, Cl or cyano group; and when Y is ##STR5## Z represents ##STR6## and A represents an alkyl group or an alkoxy group each of 1-10 carbon atoms.

Abstract: A novel compound which exhibits superior effectiveness particularly in reducing the driving voltage of liquid crystal display elements, and a liquid crystal composition containing the same are provided, which compound is a 5-alkyl-2-(3,4-difluorophenyl)pyrimidine expressed by the formula ##STR1## wherein m represents an integer of 1 to 8.

Abstract: A novel 1,4-dipyrimidinylbenzene derivative which is useful as a component constituting a liquid crystal composition which is superior in properties and also physically and chemically stable, as a material for liquid crystal display elements, and a liquid crystal composition containing the same are provided, which derivative is expressed by the formula ##STR1## wherein X represents an alkyl group or an alkoxy group each of 1 to 10 carbon atoms, methylthio group or cyano group and Y represents an alkyl group or an alkoxy group each of 1 to 10 carbon atoms.

Abstract: A liquid crystal compound having a positive value of dielectric anisotropy and a low viscosity and being capable of extending the mesomorphic range of liquid crystal composition toward its lower region, and a liquid crystal composition containing the same are provided, which compound is a trans-4-substituted-cyclohexanecarboxylic acid .beta.-(4-halogenophenyl) ethyl ester derivative expressed by the general formula ##STR1## wherein R.sup.1 represents R.sup.2, ##STR2## wherein R.sup.2 represents an alkyl group or an alkoxy group, each having 1 to 15 carbons and X represents F or Cl.

Abstract: New compounds useful as constituents of liquid crystal compositions exhibiting a negative dielectric anisotropy are provided, which are 2-cyano-4-halogenophenyl esters expressed by the general formula ##STR1## wherein R represents hydrogen atom or an alkyl group or an alkoxy group of 1 to 10 carbon atoms; ##STR2## each represent either one of ##STR3## l, m and n each represent 0 or 1 and the total of l+m+n is 1, 2 or 3; X represents F or Cl; and Y and Z each represent hydrogen atom or F or Cl.

Abstract: Novel liquid crystal compounds having a positive dielectric anisotropy and liquid crystal compositions containing the same are provided, which liquid crystal compounds are 2,3-dicyano-5-substituted pyrazines expressed by the general formula ##STR1## wherein n represents 0 or 1; X represents R, ##STR2## in the case of n=0 and R, ##STR3## in the case of n=1; and R represents a linear chain alkyl group or an alkoxy group, each of 1 to 10 carbon atoms, and which liquid crystal compositions, when sealed in a TN cell, make it possible to operate the cell under a low threshold voltage and in a small consumption of electric power.

Abstract: Novel liquid crystal compounds having superior properties and liquid crystal compositions containing the same are provided, which compounds are expressed by the general formula ##STR1## wherein R.sub.1 represents an alkyl group or an alkoxy group, each having 1 to 10 carbon atoms and R.sub.2 represents cyano group or an alkyl group having 1 to 10 carbon atoms.

Abstract: Novel compounds capable of improving various characteristics required for liquid crystal compositions when added to liquid crystal substances, and liquid crystal compositions containing the same are provided, which novel compounds are halogenopyrimidine derivatives expressed by the general formula ##STR1## wherein R.sup.1 represents an alkyl group of 1 to 10 carbon atoms, R.sup.2 represents a halogen atom of F, Cl of Br and l represents 1 or 2.

Abstract: A novel 4-halogenobenzoic acid derivative useful as a component constituting a liquid crystal composition having a large value of dielectric anisotropy and also a large value of optical anisotropy, and a liquid crystal composition containing the same are provided, which derivative is expressed by the formula ##STR1## wherein X and Y, each represent F, Cl or Br.

Abstract: Novel compounds having a small dielectric anisotropy value (.DELTA..epsilon.), a low viscosity and a small .gamma. value (ratio of saturation voltage to threshold voltage) indicating sharpness, and liquid crystal compositions containing the same are provided, which compounds are 2,4-difluorobenzene derivatives of trans-4-alkylcyclohexanes expressed by the general formula ##STR1## wherein n is 1 or 2, m is 0 or 1 and R represents an alkyl group of 1-10 carbon atoms.

Abstract: Novel liquid crystal compounds having a large positive dielectric anisotropy value and also a low viscosity and a good stability to heat, light, air and water, and liquid crystal compositions containing the same are provided, which compounds are fluorobenzene derivatives expressed by the general formula ##STR1## wherein n represents 1 or 2, X represents CN or COCH.sub.3, and R represents hydrogen atom or an alkyl group or an alkoxy group each of 1 to 15 carbon atoms.

Abstract: A liquid crystal substance having a high nematic-clearing point and a broad nematic temperature range and yet a low viscosity, and a composition containing the same, are provided, which substance is 4-unsubstituted or substituted-4"-cyano-trans,trans,trans-tercyclohexanes expressed by the general formula ##STR1## wherein R represents hydrogen atom or an alkyl group of 1 to 10 carbon atoms.

Abstract: New liquid-crystalline ester compounds which exhibit a liquid-crystalline phase within a broad temperature range and have a positive, dielectric anisotropy, and a liquid-crystalline composition comprising the same are provided which ester compounds are expressed by the general formula ##STR1## wherein R represents hydrogen atom or an alkyl group of 1 to 10 carbon atoms; ##STR2## X represents ##STR3## Y represents hydrogen atom, F, Cl or CN; and Z represents F, Cl or CN.

Abstract: Liquid crystal compounds useful as a component of liquid crystal compositions having superior actuation characteristics within a broader temperature range are provided, which compounds are carboxylic acid cyclohexyl ester derivatives expressed by the general formula ##STR1## wherein A represents ##STR2## R- or RO-; B represents ##STR3## R represents an alkyl group or an alkoxy group, both having 1 to 10 carbon atoms; and R' represents an alkyl group having 1 to 10 carbon atoms.