Abstract: An electric optical system, wherein outsides of transparent upper and lower substrates in a bend cell are placed cross-nicolly between (one or more than one) birefringent film(s) and (two or more than two) polarized plates, and wherein the said substrates facing each other have such a relationship that a pre-tilt direction of liquid crystal molecules in one substrate interface and a pre-tilt direction of liquid crystal molecules in the other substrate interface of the substrates being planar symmetrical positions against center planes of both substrates, optionally with an active switch element formed on either transparent substrate in matrix form, as well as wherein there is used an oriented memberane made of a liquid crystal compound etc. expressed by the formula 1 and/or the formula 5 as the above-mentioned liquid crystal molecules.

Abstract: Liquid crystal compositions are disclosed which satisfy various characteristics required of liquid crystal compositions used for TN-LCD or STN-LCD display mode, have a low viscosity to cope with the response at a high speed, have a high clearing point to cope with the change in environmental temperature, and have a small dependency of the pitch length on temperature. The liquid crystal compositions comprise, as a first component, at least one liquid crystalline 4-substituted-benzonitrile having a positive dielectric anisotropy, as a second component, at least one liquid crystalline compound having a small positive or negative dielectric anisotropy, and as chiral component A, at least one optically active compound expressed by general formula (X-a) or (X-b) ##STR1## wherein R.sup.0 represents an alkyl group or alkoxy group having 1 to 10 carbon atoms, X represents a halogen atom or CN, and Y represents an alkyl group having 1 to 10 carbon atoms or hydrogen atom.

Abstract: A LC composition for active matrix addressed display mode having a high voltage holding ratio and a reduced threshold voltage is provided, which composition contains:a first component consisting at least one compound of following formula (1) anda second component consisting at least one compound selected from the group of compounds of formulas (4), (5) and (6): ##STR1## wherein R.sup.1 and R.sup.2 represent C.sub.1-10 alkyl; X.sup.1 and X.sup.2 represent F, CF.sub.3, or OCF.sub.3 ; L.sup.0 -L.sup.5 represent H or F; and Z.sup.1 represents a single bond or --CH.sub.2 CH.sub.2 --.

Abstract: A LC material for TN and STN modes having a comparatively high .DELTA.n and a low viscosity is provided by a LC composition comprising a first component (formula I-c), a second component (formula II-c) and a third component (formula III or IV): ##STR1## wherein R.sup.1 is C.sub.1-10 alkyl; R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are C.sub.1-10 alkyl or C.sub.2-10 alkenyl in which alkyl and alkenyl groups one or two non-adjacent methylenes may be replaced by --O--; R.sup.6 is C.sub.1-10 alkyl, alkoxy or alkoxymethyl; Z.sup.1 and Z.sup.3 are --CH.sub.2 CH.sub.2 --, --COO-- or a single bond; Z.sup.2 is --C.tbd.C--, --COO--, --CH.sub.2 CH.sub.2 -- or a single bond; Z.sup.4 is --C.tbd.C--, --COO-- or a single bond; Q.sup.1 is H or F; A.sup.2, B, C and E are trans-1,4-cyclohexylene or 1,4-phenylene; D is trans-1,4-cyclohexylene or 1,4-phenylene in which H(s) at 2- or 3-position may be replaced by F(s); and 1 is 0 or 1.

Abstract: A LC composition for AM-LCD having a high clearing point is provided by a composition comprising a first component containing a compound(s) of formula (1) and a second component containing at least one compound expressed by any of formulas (2), (3) and (4): ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 represent C.sub.1-10 alkyl; X.sup.1 represents F or Cl; Y.sup.1 and Y.sup.2 represent H or F; Z.sup.1 and Z.sup.2 represent --CH.sub.2 CH.sub.2 --, --COO-- or a single bond; and A and B represent 1,4-phenylene or trans-1,4-cyclohexylene.

Abstract: The present invention provides a liquid crystal composition having a high clearing point, a low viscosity, a desired .DELTA.n (n.sub.e -n.sub.o) and an improved steepness of voltage-transmittance properties in the display of a supertwisted birefringence effect mode, and a liquid crystal display element having excellent contrast in which the liquid crystal composition is utilized.The present invention is directed to a liquid crystal composition characterized by containing a first component comprising a compound represented by the general formula ##STR1## wherein R.sup.1 is an alkenyl group having 2 to 8 carbon atoms, and a second component comprising a compound represented by the formula ##STR2## wherein R.sup.2 is an alkyl group having 1 to 8 carbon atoms, R.sup.3 is H or F, R.sup.4 is an alkoxy group, an alkyl group having 1 to 8 carbon atoms, F or a CN group.Furthermore, the present invention is also directed to a liquid crystal display element using the aforesaid liquid crystal composition.

Abstract: The present invention provides a liquid crystal composition wherein properties required in the super twist birefringence effect mode (SBE mode), particularly the high transparent point, low viscosity, and controllable optical isotropic value (.DELTA.n) are kept well balanced, the steepness of the voltage-transmission property is improved, and the value of N.sub.max that indicates high multiplex properties is high.A liquid crystal composition is provided containing a first component represented by the general formula: ##STR1## wherein R.sup.1 and R.sup.2 each represent an alkyl group having 1 to 8 carbon atoms,and a second component represented by the general formula: ##STR2## wherein R.sup.3 represents an alkyl group having 1 to 8 carbon atoms, or an alkenyl group having 2 to 8 carbon atoms, R.sup.4 represents H or F, R.sup.5 represents a CN-group or F, and ##STR3## represents ##STR4## and a liquid crystal display device that uses the same.

Abstract: A liquid crystal composition for twist nematic mode having improved reduction in threshold voltage and temperature dependency of the threshold voltage in a liquid crystal display element using the composition, and a liquid crystal display element are provided, which composition comprises a compound of the formula ##STR1## wherein R.sub.1 is 1-8C alkyl, R.sub.2 is F or CN and n is 1 or 2; or comprises the compound of the formula (I) as a first component and at least one member as a second component selected from compounds of the following formulas (II), (III) and (IV); ##STR2## wherein R.sub.3 is 1-8C alkyl and R.sub.4 is H or F, ##STR3## wherein R.sub.5 is 1-8C alkyl, R.sub.6 is 1-8C alkoxy or F, m is 1 or 2 and X is single bond or --COO--, and ##STR4## wherein R.sub.7 is 1-8C alkyl, R.sub.

Abstract: A nematic liquid crystal composition for multiplex drive display elements having superior characteristics, particularly a steep voltage-transmittance characteristic, is provided which composition comprises:(1) 10 to 50% by weight of first component comprising compound(s) of the formula ##STR1## wherein R.sub.1 1-8C alkyl and (2) 20 to 90% by weight of a second component comprising compounds of the following formulas (II), (III), (IV), (V) and (VI), the respective contents of which are 0-40, 0-50, 0-40, 0-40 and 0-40% by weight, the total weight of the first and second components being 60% by weight or more: ##STR2## wherein R.sub.2 is 1-10C alkyl, R.sub.

Abstract: A liquid crystal composition comprising at least one first component compound of formula (I), at least one second component compound of formula (II) and at least one third component compound of formula (III), ##STR1## wherein R.sup.1 is alkyl of 1 to 8 carbons; R.sup.2 is H or F; R.sup.3 is alkyl or alkoxy each of 1 to 8 carbons; and R.sup.4 is F, --CN, alkyl or alkoxy each of 1 to 8 carbons, the first, second and third component compounds contained in respective amounts of 20-40 wt. %, 10-40 wt. % and 20-50 wt. % and in a total amount of 70 wt. % or more in the composition is provided to improve a steepness of transmission vs. voltage curve in a SBE mode display cell which is operated at a high level of multiplexing.

Abstract: A novel ester compound which, when added to a liqud crystal composition, can raise its nematic phase-isotropic liquid phase transition point without raising its viscosity, and a liquid crystal composition containing the same are provided, which ester compound is expressed by the formula ##STR1## wherein R.sub.1 and R.sub.

Abstract: A novel phenylpyridine derivative which exhibits a positive dielectric anisotropy and is useful as a component of liquid crystal materials and also has a broad temperature range of liquid crystal phases, a high clearing point and a superior compatibility with other liquid crystal compounds or liquid crystal compositions, and a composition containing the derivative are provided. The phenylpyridine derivative is expressed by the formula ##STR1## wherein R represents an alkyl group of 1 to 10 carbon atoms, X represents H or F; Y represents F, --CN or an alkyl group or an alkoxy group of 1 to 10 carbon atoms; and m represents 0 or 1.

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 ester compound exhibiting liquid crystal phases within a broad temperature range and having a low viscosity and a high compatibility with liquid crystal compounds, and a liquid crystal composition containing the same are provided, which ester compound is expressed by the formula ##STR1## wherein X represents F or Cl; Y and Z each represent H, F or Cl and when either one of Y or Z is H, the other is F or Cl and further when X is Cl, Y and Z are not both Cl; --A-- represents a member selected from the group consisting of ##STR2## and R represents an alkyl group or an alkoxy group each of 1 to 10 carbon atoms.

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 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 novel liquid crystal ester compound which is useful as a component for TN type nematic liquid crystal composition, raising its nematic-isotropic liquid phase-isotropic liquid phase transition point without increasing its viscosity and a liquid crystal composition containing the same are provided, which ester compound is expressed by the formula ##STR1## wherein R.sup.1 represents an alkyl group or an alkoxy group each of 1 to 10 carbon atoms; ##STR2## represents ##STR3## Y represents -- COO--or --OCO--; any of ##STR4## n represents 0 or 1; and Z represents an alkyl group or an alkoxy group each of 1 to 10 carbon atoms, or a halogen atom of F, Cl or Br.

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 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: 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.