摘要:
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.
摘要:
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 element which constitutes this compound may be replaced by its isotope.
摘要:
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.
摘要:
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.1 represents cyano group, halogen atom, an alkyl group, or an alkoxy group, and R2 represents ##STR2##
摘要:
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.
摘要:
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.
摘要:
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 group having 2 to 4 carbon atoms, —(CH2)2—, —COO—, —OCO—, —C≡C—, —CH2O—, —OCH2—, or single bond any hydrogen atom in the groups may be replaced by a halogen atom provided that at least one of Z1, Z2, and Z3 represents an alkenylene group having 2 to 4 carbon atoms.
摘要:
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.
摘要:
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.
摘要:
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--.