Abstract: A tetracyclic compound expressed by the following general formula (1) wherein H1 to H12 represent hydrogen atom at least one of which is replaced by a halogen atom, when either H6 or H8 is replaced by a halogen atom, at least one of the remaining hydrogen atoms is replaced by a halogen atom; R1 and Y1 independently represent an alkyl group, alkoxy group, or alkoxyalkyl group having 1 to 20 carbon atoms, or an alkenyl group having 2 to 20 carbon atoms, one or more methylene group in R1 and Y1 may be replaced by oxygen atom, sulfur atom, dihydrosilylene group, dimethylsilylene group, —CH═CH—, or —C≡C—; and X1, X2, and X3 independently represent a covalent bond, 1,2-ethylene group, or 1,4-butylene group; and a novel liquid crystal composition comprising the tetracyclic compound and having, at the same time, a wide temperature range of a nematic phase, high optical anisotropy, and high chemical stability.

Abstract: Novel liquid crystalline compounds which have a wide temperature range of liquid crystal phase, are excellent in miscibility with other liquid crystalline compounds, have a low viscosity, are low in toxicity, and are safe; liquid crystal compositions comprising the liquid crystalline compound; and liquid crystal display devices fabricated by using the composition are provided; and the compounds are cyclohexane derivatives expressed by the general formula (1) wherein R represents an alkylene chain having 2 to 10 carbon atoms in which alkylene chain ethylene group (—CH2CH2—) may be replaced by ethenylene group (—CH═CH—) or methylenoxy group (—OCH2—); and M represents COOH or CN group.

Abstract: The present invention provides new liquid crystalline compounds having a high optical anisotropy value and excellent compatibility with the other liquid crystals, and liquid crystal composition comprising the compounds. The liquid crystalline compounds are represented by the general formula (1): wherein H1, H2, H3, H4, H5, H6, H7, H8, H9, H10, H11 and H12, each independently, represent H, F or Cl, at least one of H1, H2, H3, H4, H9, H10, H11 and H12 is F or Cl, R1 represents an alkyl group of C1-20, in which methylene groups may be replaced by —O—, —S—, —Si—, —CH═CH— or —C≡C—, any hydrogen atoms may be replaced by a halogen atom, and Y1 is replaced by R1, F, Cl, Br, I or a cyano group.

Abstract: Liquid crystalline compounds having a wide temperature range of liquid crystal phase, a high dielectric anisotropy, and a high optical anisotropy; and liquid crystal compositions and display devices containing the composition. The liquid crystalline compounds are conjugated nitrile derivatives expressed by the formula (1) ##STR1## wherein R represents an alkyl group or a fluoroalkyl group each having 1 to 10 carbon atoms, halogen atom, or cyano group provided that in the alkyl or fluoroalkyl group, one or not-adjacent two or more methylene or fluoromethylene groups may be replaced by oxygen atom or 1,2-ethenylene group; A.sub.1, A.sub.2, A.sub.3 and A.sub.4 represent 1,4-cyclohexylene group, 1,4-phenylene in which one or two hydrogen atoms on the ring may be replaced by fluorine atom, 1,3-dioxane-2,5-diyl, or pyrimidine-2,5-diyl; B.sub.1, B.sub.2, and B.sub.

Abstract: The present invention provides a liquid crystal compound having a negative dielectric constant anisotropy value of a large absolute value, a controlled optically anisotropy value, a high resistivity, a high voltage retention, and high stability against heat and ultraviolet radiation; a liquid crystal composition containing such a liquid crystal compound; and a liquid crystal display element fabricated from such a liquid crystal composition.There is disclosed a liquid crystal compound having 6,6-difluorotetrahydropyran-2,5-diyl, 6,6-difluoro-2,3-dihydro-6H-pyran-2,5-diyl, and/or 6-fluoro-3,4-dihydro-2H-pyran-2,5-diyl in the skeleton thereof; a liquid crystal composition containing such a liquid crystal compound; and a liquid crystal display element fabricated from such a liquid crystal composition.

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 crystalline compounds which have excellent compatibility with other liquid crystal materials, especially at low temperatures, high voltage holding ratio, low threshold voltage, their small temperature dependency, high .DELTA.n, and broad liquid phase temperature range, the compounds being represented by formula (1)Ra--A.sub.1 --Z.sub.1 --A.sub.2 --Z.sub.2 --(--A.sub.3 --Z.sub.3 --).sub.m --A.sub.0 --Rf (1)(wherein m is 0 or 1; A.sub.0, A.sub.1, A.sub.2 and A.sub.3 represent a six-membered ring, ring A.sub.0 is 1,4-phenylene which may be substituted with 1 to 3 of F and/or Cl, rings A.sub.1, A.sub.2 and A.sub.3, independently of one another, are selected from trans-1,4-cyclohexylene, 1,4-phenylene which may be substituted with one or more halogen atoms, cyclohexene-1,4-diyl or 1,3-dioxane-2,5-diyl; Z.sub.1, Z.sub.2 and Z.sub.3 represent a bridge between the rings and independently of one another, are selected from --(CH.sub.2).sub.2 --, --(CH.sub.2).sub.4 --, --CH.sub.2 O--, --OCH.sub.

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: A compound represented by the following general formula (1) is provided. This has broader temperature range of nematic phase, lower viscosity and higher miscibility with other liquid crystal compounds at low temperature than those of conventional liquid crystal compounds, and the compounds have high chemical stability. ##STR1## wherein H.sub.1 to H.sub.8 represent independently a hydrogen atom or a halogen atom, provided that at least one of them is a halogen atom; R.sub.1 represents a moiety which is an alkyl group having 2 to 20 carbon atoms provided that one or more methylene groups (--CH.sub.2 --) which are not successive in the alkyl group are replaced with an oxygen atom (--O--) in the form of ether; Y.sub.1 represents an alkyl group having 1 to 20 carbon atoms, and one or more methylene groups in Y.sub.1 independently may be replaced with an oxygen atom, a sulfur atom, a dihydroxysilyl group, a dimethylsililene group, --CH.dbd.CH-- or --C.tbd.C--; X.sub.1 to X.sub.

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: An object of the present invention is to provide a novel liquid crystalline compound having a large dielectric anisotropy, small change in threshold voltage depending on temperature, and an improved solubility to other liquid crystal materials at low temperatures, and expressed by the following general formula (1): ##STR1## wherein R represents, for example, an alkyl group or alkoxy group having 1 to 10 carbon atoms, m and n are independently 0 or 1, A.sub.1, A.sub.2, and A.sub.3 are independently, for example, trans-1,4-cyclohexylene group, 1,4-phenylene group one or more hydrogen atoms on the ring of which may be replaced by F, Z.sub.1, Z.sub.2, and Z.sub.3 independently represent --COO--, --OCO--, --(CH.sub.2).sub.2 --, --CH.sub.2 O--, --OCH.sub.2 --, or a covalent bond provided that at least one of Z.sub.1, Z.sub.2, and Z.sub.3 represents ester bond, --CH.sub.2 O--, or --OCH.sub.2 --, X represents, for example, CF.sub.3, CF.sub.2 H, and Y represents H or F.

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: A propiolonitrile derivative of formula (I) ##STR1## wherein n1 and n2 each independently stand for 0 or 1; A1, A2 and A3 each independently represent a 1,4-phenylene, a 1,4-phenylene substituted by one or more fluorine atoms, a trans-1,4-cyclohexylene, a 1,3-dioxane-2,5-diyl or a 1,3-pyrimidine-2,5-diyl; Z1, Z2 and Z3 each independently represent a single bond, ethylene, ethenylene, ethynylene, carbonyloxy, oxycarbonyl, methyleneoxy, oxymethylene, 1,4-butylene or 1,4-butenylene; R represents a saturated, aliphatic hydrocarbyl radical of 1-10 carbons, an unsaturated, aliphatic hydrocarbyl radical of 2-10 carbons, a saturated or unsaturated, aliphatic hydrocarbyl radical of 1-10 carbons containing one or more ether linkages (--O--) in the chain and a saturated or unsaturated, fluoro-substituted aliphatic hydrocarbyl radical of 1-10 carbons containing one or more fluorine atoms in the chain; X1 and X2 each independently represent H, F or Cl;provided that at least one of X1 and X2 is F or Cl, when both n1 and n2

Abstract: Disclosed are (A) a liquid crystalline compound of the general formula: ##STR1## wherein X.sub.1 stands for a hydrogen atom, cyano group, a halogen atom, or an alkyl group with 1-20 carbon atoms, and one or more methylene groups in the alkyl group may be replaced by --CH.dbd.CH--, --.tbd.C--, or oxygen atoms and one or more hydrogen atoms may be substituted by halogen atoms; X.sub.2 stands for a hydrogen atom, an alkyl group with 1-10 carbon atoms, or a substituent of --(A.sub.4 --Z.sub.4).sub.s --A.sub.6 --X.sub.3 ; l, m, n and s each stands for an integer of 0 or 1, and p, and q each stands for an integer of 0-5; X.sub.3 for an alkyl group with 1-10 carbon atoms; Z.sub.1 -Z.sub.4 each independently stands for a covalent bond or an alkylene group with 1-5 carbon atoms, and one or more methylene groups in the alkylene group may be replaced by --CH.dbd.CH--, --C.tbd.C--, or an oxygen atom and one or more hydrogen atoms i the alkylene group may be substituted by halogen atoms; the ring A.sub.1 -A.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: A compound expressed by the general formula (1): whereinR.sup.1 denotes an alkyl group having 1 to 20 carbon atoms in which one or more methylene groups in said group may be replaced by oxygen atoms or --CH.dbd.CH-- and one or more hydrogen atoms in said group may be replaced by fluorine or chlorine atoms, with the proviso that two or more methylene groups may not be continuously replaced by oxygen atoms;Y.sup.1 denotes a halogen atom, CN, CF.sub.3, CHF.sub.2 or an alkoxy group having 1 to 5 carbon atoms, in which at least one hydrogen atom is replaced by a fluorine atom and one or more hydrogen atoms may be further replaced by chlorine atoms;Z.sup.1, Z.sup.2 and Z.sup.3 each independently denote a covalent bond, --CH.sub.2 CH.sub.2 --, --CH.dbd.CH-- or CF.sub.2 O--, with the proviso that at least one of Z.sup.1, Z.sup.2, and Z.sup.3 is --CF.sub.2 O--;rings A.sup.1, A.sup.2 and A.sup.

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: The present invention is to provide liquid crystalline compounds having a wide temperature range of a liquid crystal phase, low viscosity, and large ratio of elastic constants; liquid crystal compositions comprising the compound; and liquid crystal display devices comprising the composition; the liquid crystalline compounds being fluoroalkenyl derivatives expressed by the general formula (1) ##STR1## wherein A.sub.1, A.sub.2, A.sub.3, and A.sub.4 independently represent trans-1,4-cyclohexylene group or 1,4-phenylene group; Z.sub.1, Z.sub.2, and Z.sub.3 independently represent --(CH.sub.2).sub.2 --, --CH.dbd.CH--, --C.ident.C--, or a single bond; Q represents H or F; l is an integer of 1 to 5; m, n, and o are independently an integer of 0 to 5; p and q are independently an integer of 0 or 1; and each element which constitutes the derivatives may be an isotope of the element.

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: There is provided a liquid crystal composition in particular with a low threshold voltage and a wide range of nematic phase temperature (with high TNI point and low TC), while satisfying various properties required for liquid crystal compositions for active matrix type liquid crystal display elements. The composition contains, for example, compounds represented by general formulas (1-1) and (2-1): ##STR1## where each R.sub.1 independently represents an alkyl group having 1 to 10 carbon atoms; X.sub.1 represents H or F; and each X.sub.2 independently represents F, OCF.sub.3, CF.sub.3, or OCF.sub.2 H.