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## each represent ##STR3## X represents ##STR4## Y represents hydrogen atom, F, Cl or CN; and Z represents F, Cl or CN.

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 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.

Abstract: Liquid-crystalline compounds which exhibit a liquid crystalline phase within a broader temperature range and also have a high transparent point and yet a low viscosity, and liquid-crystalline compositions containing at least one kind of the above compounds are provided, which compounds are high temperature liquid-crystalline substances consisting of 4 or 5 six-member-rings, expressed by the general formula ##STR1## wherein R and R' each represent hydrogen atom or an alkyl group or an alkoxy group, each having 1 to 10 carbon atoms; ##STR2## and n represents 0 or 1.

Abstract: Liquid crystal compounds which exhibit a liquid crystal phase within a broad temperature range and have a high clearing point and nevertheless a low viscosity, and liquid crystal compositions containing the same are provided, which liquid crystal compounds have positive dielectric anisotropy values and are expressed by the general formula ##STR1## wherein R represents hydrogen atom or an alkyl group of 1 to 10 carbon atoms; ##STR2## Y represents H or F; and X represent a halogen atom or CN.

Abstract: Liquid crystal compounds used for liquid crystal display elements are provided, which exhibit a liquid crystal phase within a broad temperature range and also have a low viscosity. The compounds are cyano-mono- or diphenylbicyclohexane derivatives expressed by the general formula ##STR1## wherein R represents hydrogen or an alkyl group of 1 to 15 carbon atoms and n is 1 or 2.

Abstract: Benzene derivatives useful as a component of liquid crystal compositions are provided which are expressed by the general formula ##STR1## wherein R represents a hydrogen atom or an alkyl group of 1 to 10 carbon atoms; R' represents a hydrogen atom, an alkyl group of 1 to 10 carbon atoms or an alkoxy group of 1 to 10 carbon atoms; and ##STR2## represents ##STR3## The derivatives exhibit small values of positive dielectric anisotropy; have broader liquid crystal temperature ranges; and in particular, have higher liquid crystalline-transparent points and yet have lower viscosities.

Abstract: New liquid crystal compounds having a low viscosity and nevertheless having a high transparent point and a broad nematic temperature range, and liquid crystal compositions containing the same are provided. The compounds are liquid-crystalline halogenobenzene derivatives expressed by the general formula ##STR1## wherein R represents an alkyl group having 1 to 10 carbon atoms; ##STR2## and X and Y each are H, F or Cl, at least one of X and Y being F or Cl.

Abstract: Novel fluorine-containing organic compounds having a positive dielectric anisotropy, useful as component(s) of liquid crystal compositions, and liquid crystal compositions containing the same are provided. The compounds have the general formula ##STR1## R.sub.1 and R.sub.3 both are 1-10 C alkyl or alkoxy; R.sub.2 is H or 1-10 C alkyl; and R.sub.4 is 1-10 C alkyl.