Abstract: Liquid crystal compositions comprising at least two components wherein the first component is at least one selected from propiolonitrile derivatives containing 2-4 rings and the second component is at least one selected from the liquid crystalline compounds containing 2-4 rings and a saturated or unsaturated hydrocarbon group of up to 10 carbons. The propiolonitrile derivatives of the first component are those wherein each ring is trans-1,4-cyclohexylene, 1,4-phenylene, 2,6-dioxan-1,4-diyl or 2,6-pyrimidine-1,4-diyl, each bridge between the rings is ethylene, carbonyloxy or covalent bond and the terminal group at one end is hydrocarbon group of up to 10 carbons which may contain at least one ether bond in the chain.

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: An object of the present invention is to provide organosilicon compounds having an excellent miscibility with other liquid crystal materials, low viscosity, and improved threshold voltage; to provide liquid crystal compositions comprising the organosilicon compound; and to provide liquid crystal display devices comprising the liquid crystal composition. The organosilicon compounds are expressed by the general formula (1)Ra--A.paren open-st.Z.sub.1 --A.sub.1 .paren close-st..sub.m .paren open-st.Z.sub.2 --A.sub.2 .paren close-st..sub.n .paren open-st.Z.sub.3 --A.sub.3 .paren close-st..sub.o Rb (1)wherein at least one of Ra, Rb, Z.sub.1, Z.sub.2, and Z.sub.3 has --SiH.sub.2 --; Ra represents hydrogen atom or an alkyl group having 1 to 20 carbon atoms; at least one --CH.sub.2 -- in the alkyl group may be replaced by --SiH.sub.2 --, --O--, --S--, --CO--, --CH.dbd.CH--, --C.tbd.C--, or 1,3 -cyclobutylene; Rb represents a group selected from Ra, a halogen atom, or CN; each of A, A.sub.1, A.sub.2, and A.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.

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: A liquid crystal composition which comprises at least one phenylbenzoate derivative represented by formula (1) ##STR1## wherein R.sub.1 is a hydrogen atom or an alkyl group of 1-10 carbons and others; X is a hydrogen atom or a halogen atom; A and B each independently represent a 1,4-phenylene group or a trans-1,4-cyclohexylene group and others; Z.sub.1 and Z.sub.2 each independently represent --CH.sub.2 CH.sub.2 --, --CO--O--, a covalent bond and others; m and n each independently represent 0 or 1.

Abstract: A liquid crystalline compound having a remarkably high .DELTA.n and good miscibility with other liquid crystalline compounds, and expressed by the general formula (1) ##STR1## wherein R.sub.1 represents, for example, a halogen atom, cyano group, or an alkyl or alkenyl group of 1 to 15 carbon atoms in which alkyl or alkenyl group hydrogen atom may be replaced, for example, by fluorine atom, and one or not-adjacent two or more methylene groups may be replaced by oxygen atom, --CH.dbd.CH-- or --C.tbd.C--; R.sub.2 represents an alkyl group of 1 to 10 carbon atoms or hydrogen atom; rings A.sub.1, A.sub.2, A.sub.3, and A.sub.4 independently represent, for example, 1,4-cyclohexylene or 1,4-phenylene in which hydrogen atom may be replaced by a halogen atom or cyano group; Z.sub.1, Z.sub.2, and Z.sub.3 independently represent, for example, a covalent bond or --CH.sub.2 CH.sub.2 --; s and t are 0 or 1; u is an integer of 1 to 5; and each of the elements in the general formula may be its isotope.

Abstract: The present invention provides a liquid crystal composition satisfying many characteristics required to liquid crystal compositions for AM-LCD, having a preferable .DELTA.n value in proportion to the cell thickness, and having very low threshold value suitable for driving at low voltage.The liquid crystal composition of the present invention comprises as the first constituent at least one compound selected from the group consisting of compounds represented by particular formula (I) and as the second constituent at least one compound selected from the group consisting of compounds represented by particular formulas (II-1)-(II-7).

Abstract: There is provided an electrically and chemically stable liquid crystalline compound which exhibits a significantly large value of De and a high voltage holding ratio. The compound is a phenyldioxane derivative represented by formula (1): ##STR1## wherein R represents a C1-C20 alkyl group; each of n1 and n2 represents 0 or 1; each of Q.sub.1 through Q.sub.6 represents a hydrogen atom, a fluorine atom, or a chlorine atom, provided that Q.sub.3 is a fluorine atom or a chlorine atom when n2 is 0, and that at least one of Q.sub.1 and Q.sub.3 is a fluorine atom or a chlorine atom when n2 is 1; each of Za and Zb represents a single bond, --COO--, or --CF.sub.2 O--; Zc represents a single bond or --CH.sub.2 CH.sub.2 --; Y represents a hydrogen atom, a halogen atom, or a C1-C5 halogenated alkyl group in which one or more non-adjacent methylene groups may be replaced by oxygen atoms or sulfur atoms; and each of the elements that constitute the compound may comprise isotopes of the element.

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: In order to provide novel compounds which are useful as liquid crystal materials for low voltages in several liquid crystal displays, have a large dielectric anisotropy, and are low in viscosity; and to improve characteristics of liquid crystal compositions, difluorooxymethane derivatives expressed by the following general formula (I) and liquid crystal compositions containing the compound are proposed ##STR1## wherein each of l, m, and n is 0 or 1, rings A.sub.1 to A.sub.3 independently represent six-membered rings such as trans-1,4-cyclohexylene and 1,4-phenylene, Z.sub.1 to Z.sub.3 independently represent a bonding group such as covalent bond and --CH.sub.2 CH.sub.2 --, L.sub.1 to L.sub.4 independently represent hydrogen atom or halogen atom, and X represents a group such as halogen atom and OCF3.They are useful as liquid crystal materials for low voltages in several modes such as active matrix mode and STN mode.