Abstract: Liquid crystalline compounds which have a wide temperature range of liquid crystal phase, low viscosity, and improved threshold voltage; liquid crystal compositions; and liquid crystal display devices comprising the composition can be provided; and the liquid crystalline compounds are expressed by the general formula (1) Ra—A1—Z1—A2—Z2—A3—(Z3—A4)m—Rb  (1) wherein Ra represents an alkyl group having 1 to 20 carbon atoms one or more —CH2— in which alkyl group may be replaced by —O— or the like, and one or more hydrogen atoms in which alkyl group may be replaced by a halogen atom; Rb represents Ra, a halogen atom, or cyano group; A1, A2, A3, and A4 independently represent a divalent ring group; Z1, Z2, and Z3 independently represent an alkenylene group having 2 to 4 carbon atoms, —COO—, a covalent bond, or the like provided that at least one of Z1 to Z3 represents an alkenylene group having 2 to 4 carbon atoms, and at

Abstract: The invention is to provide liquid crystalline compounds which have a low viscosity, high negative dielectric anisotropy, high resistivity, and high voltage holding ratio, and are stable against heat and ultraviolet light; to provide liquid crystal compositions comprising the liquid crystalline compound; and to provide liquid crystal display devices using the liquid crystal composition therein; the liquid crystalline compound is expressed by the general formula (1)  wherein R1 and Y1 represent an alkyl group having 1 to 20 carbon atoms; X1, X2, and X3 independently represent single bond, 1,2-ethylene group, vinylene group, —COO—, —CF2O—, or —OCF2—; ring A1, ring A2, ring A3, and ring A4 independently represent trans-1,4-cycloliexylene, or 1,4-phenylene hydrogen atom on the ring may be replaced by fluorine atom or chlorine atom provided that at least one of ring A2, ring A3, and ring A4 represents 2,3-difluoro-1,4-phenylene; m and n are 0 or 1, and ea

Abstract: The liquid crystalline compound is expressed by the general formula (1) Ra-A1-Z1-A2-Z2-A3-Z3-A4-Rb   (1) wherein Ra represents an alkenyl group having 2 to 20 carbon atoms or an alkyl group having 1 to 20 carbon atoms any methylene group (—CH2—) in the alkenylene or alkyl group may be replaced by —O—, —S—, —CO—, —CH═CH—, or —C≡C—, but in no case —O— and/or —S— continues, and any hydrogen atom in Ra may be replaced by a halogen atom; Rb represents Ra, a halogen atom, or cyano group provided that at least one of Ra and Rb represents a group having double bond; A1, A2, A3, and A4 independently represent trans-1,4-cyclohexylene group, 1,4-phenylene group any hydrogen atom on the ring may be replaced by fluorine atom or cyano group, cyclohexenediyl group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl group, or 1,3-dioxane-2,5-diyl group; and Z1, Z2, and Z3 independently represent an alkenylene gro

Abstract: The invention is to provide liquid crystalline compounds which have a low viscosity, high negative dielectric anisotropy, high resistivity, and high voltage holding ratio, and are stable against heat and ultraviolet light; to provide liquid crystal compositions comprising the liquid crystalline compound; and to provide liquid crystal display devices using the liquid crystal composition therein; the liquid crystalline compound is expressed by the general formula (1) wherein R1 and Y1 represent an alkyl group having 1 to 20 carbon atoms; X1, X2, and X3 independently represent single bond, 1,2-ethylene group, vinylene group, —COO—, —CF2O—, or —OCF2—; ring A1, ring A2, ring A3, and ring A4 independently represent trans-1,4-cyclohexylene, or 1,4-phenylene hydrogen atom on the ring may be replaced by fluorine atom or chlorine atom provided that at least one of ring A2, ring A3, and ring A4 represents 2,3-difluoro-1,4-phenylene; m and n are 0 or 1, and each elem

Abstract: Liquid crystalline compounds expressed by the following formula (1), liquid crystal compositions thereof obtained by combination with specified liquid crystal compounds, and liquid crystal display devices using them, wherein, A1, A2, A3 and A4 denote each independently trans-1,4-cyclohexylene group etc.; Z1, Z2 and Z3 denote each independently —(CH2)2— etc.; Q1 and Q2 denote each independently H, F, Cl or Br; Q3 and Q4 denote each independently F, Cl or Br; 1, m and n denote each independently an integer of from 0 to 5; and p and q denote each independently an integer of 0 or 1.

Abstract: A compound represented by the following general formula (I), a liquid crystal composition comprising the same, and a liquid crystal element using this liquid crystal composition. ##STR1## (wherein B.sub.1 and B.sub.2 represent independently a trans-1,4-cyclohexylene group or a 1,4-phenylene group wherein at least one hydrogen atom on the six-membered ring is optionally substituted by a halogen atom, Y represents a halogen-substituted alkyl group having 1 to 3 carbon atoms, a halogen-substituted alkoxy group having 1 to 3 carbon atoms, a cyano group, a fluorine atom or a chlorine atom, X represents a fluorine atom, a chlorine atom or a hydrogen atom, R.sub.1 represents an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, n and m represent independently 1 or 2 and p represents 0 or 1.

Abstract: A liquid crystalline compound represented by the general formula (1) ##STR1## wherein R.sub.1 represents an alkyl or alkoxy group having 1 to 10 carbon atoms, a cyano group, a halogen atom, or an alkyl or alkoxy halide group having 1 to 4 carbon atoms; R.sub.2 represents an alkyl group having 1 to 10 carbon atoms; rings A.sub.1, A.sub.2, A.sub.3, and A.sub.4 each independently represent a 1,4-phenylene or 1,4-cyclohexylene group; Z.sub.1, Z.sub.2, and Z.sub.3 each independently represent a covalint bond, --CH.sub.2 CH.sub.2 --, --CH.dbd.CH--, --C.tbd.C-- or --COO--; 1 and m are 0 pr 1; and n is 0 to 10.

Abstract: Liquid crystal compositions which have excellent miscibility at low temperatures, a properly large optical anisotropy, and a small threshold voltage while satisfying various characteristics required of liquid crystal compositions for active matrix mode liquid crystal display devices. The compositions contain, as a first component, at least one compound expressed by any one of formulas ##STR1## and as a second component, at least one compound expressed by any one of formulas ##STR2## wherein R represents a straight chain alkyl group having 1 to 10 carbon atoms, X represents CF.sub.3 or OCF.sub.3, X.sup.2 represents fluorine or OCF.sub.3, each Y represents, independently of each other, a hydrogen or fluorine atom, and m is 1 or 2.

Abstract: The present invention is to provide a liquid crystallineThe present invention is concerned with a liquid crystalline compound expressed by general formula (1) ##STR1## wherein R.sub.1 represents cyano group, halogen atom, or a straight or branched alkyl group or halogenated alkyl group having 1 to 20 carbon atoms, one or not-adjacent two CH.sub.2 groups in the alkyl group or halogenated alkyl group may be replaced by oxygen atom or --CH.dbd.CH-- group; R.sub.2 and R.sub.2 ' represent hydrogen atom, halogen atom, or an alkyl group having 1 to 9 carbon atoms; X.sub.1, X.sub.2, and X.sub.3 independently represent --CH.sub.2 CH.sub.2 --, --CO--O--, --O--CO--, --CH.dbd.CH--, --C.tbd.C--, --(CH.sub.2).sub.4 --, --CF.sub.2 O--, --OCF.sub.2 --, --CH.sub.2 O--, --OCH.sub.

Abstract: The present invention provides a liquid-crystalline compound which has a reduced viscosity, a wide liquid crystal temperature range (high clearing point), a high chemical stability (extremely high specific resistance, high voltage holding ratio) and a high solubility with other liquid-crystalline compound(s) and preferably has a proper refractive index anisotropy. The present invention also provides a liquid crystal composition having excellent properties. The liquid-crystalline compound is represented by the following general formula (1): wherein R and R' each independently represents a C.sub.1-20 alkyl or halogenated alkyl group or a group obtained by replacing one or more --CH.sub.2 -- groups in the alkyl group by any of --O--, --S--, --CH.dbd.CH-- or --C.tbd.C--, provided that two or more --CH.sub.2 -- groups are not consecutively replaced by either --O-- or --S--; and Z.sub.1 and Z.sub.2 each independently represents a covalent bond or 1,2-ethylene group, provided that when both Z.sub.1 and Z.sub.

Abstract: Liquid crystalline compounds are disclosed which compounds are expressed by general formula (1) ##STR1## wherein R.sub.1 represents an alkyl group having 1 to 10 carbon atoms, ring A represents 1,4-phenylene or 1,4-cyclohexylene, each of X.sub.1, X.sub.2, X.sub.3, and X.sub.4 independently represents hydrogen atom or fluorine atom, Y.sub.1 represents CF.sub.3 or OCF.sub.3, and each of m, n, and p is independently an integer of 1 or 0. The liquid crystalline compounds have a wide temperature. The liquid crystalline compounds have a wide temperature range of nematic phase, low viscosity, large positive .DELTA..epsilon., high chemical stability, high miscibility with other liquid crystalline compounds at low temperatures, small temperature dependency of viscosity and .DELTA..epsilon., extremely high specific resistance (high voltage holding ratio), and good UV stability, and are preferably used for TFT.

Abstract: The present invention is concerned with a liquid crystalline compound expressed by general formula (1) ##STR1## wherein R.sub.1 represents cyano group, halogen atom, or a straight or branched alkyl group or halogenated alkyl group having 1 to 20 carbon atoms, one or not-adjacent two CH.sub.2 groups in the alkyl group or halogenated alkyl group may be replaced by oxygen atom or --CH.dbd.CH-- group; R.sub.2 and R.sub.2 ' represent hydrogen atom, halogen atom, or an alkyl group having 1 to 9 carbon atoms; X.sub.1, X.sub.2, and X.sub.3 independently represent --CH.sub.2 CH.sub.2 --, --CO--O--, --O--CO--, --CH.dbd.CH--, --C.tbd.C--, --(CH.sub.2).sub.4 --, --CF.sub.2 O--, --OCF.sub.2 --, --CH.sub.2 O--, --OCH.sub.

Abstract: An acrylonitrile derivative expressed by the following general formula I, a composition comprising the derivative and having an improved viscosity and optical anisotropy, and a liquid crystal display device: ##STR1## wherein rings A.sup.1 to A.sup.3 represent phenylene, cyclohexylene, dioxane, or pyrimidine, R.sup.

Abstract: Liquid crystal compositions which have a low threshold voltage, excellent miscibility at low temperatures, and a wide range of a nematic phase while satisfying various characteristics required of liquid crystal compositions for active matrix mode liquid crystal display devices. The compositions contain, as a first component, at least one compound expressed by any one of formulas ##STR1## and as a second component, at least one compound expressed by any one of formulas ##STR2## wherein each of the formulas, X represents CF.sub.3 or OCF.sub.3, each Y represents, independently of each other, a hydrogen or fluorine atom, m is 1 or 2, and n is an integer or 1 to 10.

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: Liquid crystal compositions having a small value of .gamma. (V.sub.10 /V.sub.90) and a small .tau. (fast response speed) in order to cope especially with high speed response, while satisfying various characteristics required of STN display mode. These compositions comprise at least one compound expressed by formula (I) as a first component; expressed by any one of formulas (II-a) to (II-d) as a second component; and expressed by formula (III) or (IV) as a third component; and as a fourth component, a chiral component in the amount necessary for maintaining the ratio d/P of the cell thickness d (.mu.m) to the pitch length of twist P (.mu.m) in the range of 0.4 to 0.6 when the liquid crystal composition is used for liquid crystal display devices. ##STR1## wherein R.sup.1 to R.sup.9 represent an alkyl group having 1 to 10 carbon atoms; Z.sup.0 to Z.sup.4 represent, for example, --CH.sub.2 CH.sub.2 --; A.sup.1 to A.sup.

Abstract: A novel liquid crystalline compound having a sufficiently large .DELTA.n, a superior, low temperature compatibility with other liquid crystals and a chemical stability; a liquid crystal composition containing the above compound; and a display element using the above liquid crystal composition are provided,which liquid crystalline compound is expressed by the formula (1): ##STR1## wherein R.sub.1 is an alkyl group or alkoxy group of 1 to 10C, cyano group or a halogen atom; R.sub.2 is an alkyl group of 1 to 5C wherein one methylene group (--CH.sub.2 --) may be replaced by oxygen atom; X.sub.1 and X.sub.2 each independently are hydrogen atom or a halogen atom; A and B each independently are single bond, 1,4-phenylene ring or 1,4-cyclohexylene ring which may be substituted by halogen atom may be; and p is 1 to 5.

Abstract: Liquid crystalline compounds are disclosed which are expressed by the following general formula (1) ##STR1## wherein R.sub.1 represents a branched alkyl group having 3 to 10 carbon atoms, ring A represents 1,4-phenylene group or 1,4-cyclohexylene group, Z.sub.1 and Z.sub.2 independently represent a single bond or 1,2-ethylene group, respectively, X.sub.1, X.sub.2, X.sub.3, and X.sub.4 independently represent fluorine atom or hydrogen atom, respectively, and Y.sub.1 represents oxygen atom or a single bond. The compounds are excellent in compatibility with other liquid crystalline compounds, and have a large positive value of dielectric anisotropy, extremely low viscosity, extremely high specific resistance (high voltage holding ratio), and excellent UV stability.

Abstract: Liquid crystalline alkenyl cyclohexane compounds of formula (I) having a nematic phase over a broad temperature range, a higher elastic constant ratio K.sub.33 /K.sub.11 and a lower viscosity, liquid crystal compositions comprising the above compounds and liquid crystal display elements using the liquid crystal compositions. ##STR1## wherein R.sub.1 is an alkyl group of 1-15 carbons, an alkenyl group of 2-15 carbons or an alkyl or alkenyl group in which at least one of non-adjacent methylene groups (--CH.sub.2 --) is replaced by --O--, --S--, --C.tbd.C-- or --COO--; R.sub.2 is a hydrogen atom or an alkyl group of 1-10 carbons; m is 0-5; when m is 2 or more, any one methylene group in --(CH.sub.2).sub.m -- may be replaced by --O--; and the rings A.sub.1, A.sub.2 and A.sub.3 are independently a 1,4-cyclohexylene, a cyclohexene-1,4-diyl or a 6-membered ring group, one or two --CH.sub.2 -- groups in said rings optionally replaced by --O-- or --S--.

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.