Abstract: There is provided a method for producing a polarizing film having far superior water resistance to conventional polarizing films by contacting a liquid containing cationic polymers with a surface of a polarizing film.

Abstract: [Problem] In the present invention, it is an object to improve display quality by improving response speed of a liquid crystal element in a liquid crystal display device, in particular, response speed in the case of falling. [Means for Solving the Problems] In the present invention, it is characterized that a liquid crystal layer is divided into plural regions (domains) substantially by mixing a chemical compound including a liquid crystal skeleton in a liquid crystal layer exisiting liquid crystal molecules as a technique to improve response speed of a liquid crystal element in a liquid crystal display device for solving the above problem.

Abstract: The invention relates to compensation films for liquid-crystal displays with additions of rod-shaped liquid crystals mentioned below, to polarizer plates which have at least one compensation film of this type, to liquid-crystal displays which have compensation films of the said type, and to processes for the production of the said compensation films, polarizer plates and liquid-crystal displays, to the use of the compounds described in greater detail below as additions to compensation films for liquid-crystal displays, and to further subject-matters of the invention which can be seen below.

Abstract: Optical films are described having a polymerized microstructured surface that comprises the reaction product of a polymerizable resin composition comprising at least one polymerizable ethylenically unsaturated triphenyl monomer. Also described are certain triphenyl (meth)acrylate monomers and polymerizable resin compositions.

Abstract: There are provided an optical compensation film including an alignment film whose adhesiveness to a substrate and a liquid crystal layer and alignment property are excellent when a novel substrate is used to solve the problem regarding deteriorated durability being caused when a retardation film including a liquid crystal film is used under a hot and humid environment, and an integrated polarizing plate comprising the same. The O-plate includes a substrate; an alignment film prepared by coating the substrate with a composition for an alignment film that is composed of polyvinyl alcohol, a multifunctional acrylate monomer, a compatibilizing agent, a photo initiator and a solvent, followed by undergoing drying, curing and rubbing processes; and a splay-aligned liquid crystal film formed on the alignment film.

Abstract: The present invention relates to liquid-crystalline compounds having two fluorinated biphenyl units, a terminal trifluoromethyl or trifluoromethoxy group and a —CF2O— bridge between the two fluorinated biphenyl units. The invention also relates to liquid-crystalline media prepared therewith and to liquid-crystal display devices (LC displays) containing these media.

Abstract: The present invention relates to a liquid-crystalline medium, characterised in that it contains a polymerisable component (A) containing one more polymerisable compounds and a liquid-crystalline component (B) containing one more compounds of the general formula I in which R, rings A1 and A2, Z1, Z2, Y1, Y2, X0 and r are as defined in Claim 1.

Abstract: A transparent substrate with optical compensation ability comprises polyimide having the following chemical formula: wherein A and A? are cyclic aliphatic or aromatic compounds, B and B? are cyclic aliphatic or aromatic compounds. In particular, the refractive index of the transparent polyimide is nx=ny>nz, that is, it has ability of adjusting the negative type c-plate phase difference, wherein nx represents the lateral refractive index, ny represents the longitudinal refractive index, nz represents the vertical refractive index along the thickness direction, and m and n are between 10 and 10,000.

Abstract: Inorganic nanoparticles having a refractive index of at least 1.60 wherein the nanoparticles are surface modified with a surface treatment comprising a compound comprising a carboxylic acid end group and a C3-C8 ester repeat unit.

Abstract: Microstructured films such as brightness enhancing films, polymerizable resin compositions comprising an organic component and surface modified nanoparticles, and surface modified nanoparticles are described. The microstructured film has a polymerized structure comprising the reaction product of the polymerizable resin composition (e.g. having a refractive index of at least 1.58). The cured nanocomposite (e.g. structure) can exhibit improved crack resistance. In some embodiments, the flexibility is expressed in terms of a cylindrical mandrel bend test property (e.g. a mandrel size to failure of less than 6 mm or a mandrel size to failure according to the equation D=1000(T/0.025?T) wherein T is the thickness in millimeters of a (e.g. preformed base layer). In other embodiments, the flexibility is expressed in terms of a tensile and elongation property (e.g. a tensile strength at break of at least 25 MPa and an elongation at break of at least 1.75%).

Abstract: A liquid crystal display includes a first substrate, a second substrate, and a liquid crystal layer. The first substrate includes a first insulating substrate, in which a pixel area is defined, a gate line formed on the first insulating substrate, a data line crossing the gate line, and a thin film transistor connected to the gate line and the data line. The second substrate is opposite to the first substrate. The liquid crystal layer is interposed between the first and second substrates and includes a liquid crystal composition with a nematic-isotropic phase transition temperature (Tni) of 79° C. or above.

Abstract: A novel optical compensatory sheet comprising an optically anisotropic layer comprising at least one liquid crystal compound, at least one cellulose ester, and at least one polymer A comprising at least one repeating unit derived from a monomer having a fluoro-aliphatic group, and at least one repeating unit having a group selected from the group consisting of carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO3H) or a salt thereof and a phosphonoxy group {—OP(?O) (OH)2} or a salt thereof, is disclosed. A novel optical compensatory sheet comprising an optically anisotropic layer comprising at lest one liquid crystal compound at least one polymer C, having a weight average molecular weight of not less than 5000 and less than 20000, represented by a formula (1b), and at least one polymer D, having a weight average molecular weight of not less than 20000, represented by a formula (1b), is also disclosed.

Abstract: The invention relates to a liquid-crystalline medium based on a mixture of polar compounds having negative dielectric anisotropy, which contains at least one compound of the formula I and at least one compound of the formula II in which R1, R2, R3, R4, ring A, Z1, Z2 and m are as defined in Claim 1, and to the use thereof for an active-matrix display based on the ECB, VA, PS-VA, FFS, PALO or IPS effect.

Abstract: An optical film comprising at least one compound represented by formula (1) is disclosed. In the formula, Y11, Y12 and Y13 each independently represent methine or a nitrogen atom; R11, R12 and R13 each independently represent formula (A), (B) or (C) or a hydrogen atom, provided that at least two of R11, R12 and R13 each independently represent formula (A), (B) or (C). In the formulae, L12, L22, and L32 each represent a 5-membered heterocyclic group.

Abstract: The present invention relates to a retardation film, a method for manufacturing the same, and a liquid crystal display device including the same. More particularly, the present invention relates to a retardation film that includes 1) an acryl-based film, and 2) a coating layer of a negative C type material, the retardation film according to the exemplary embodiment of the present invention may be applied to an IPS (in-plane switching) mode liquid crystal display, and it is possible to control a ratio of an in-plane retardation value and a thickness retardation value of the retardation film.

Abstract: A composition, including a liquid crystal polymer or oligomer having a terminal hydroxyl group, and a cross-linking agent including a bismaleimide compound, an epoxy resin or a combination thereof, wherein the liquid crystal polymer or oligomer is represented by Formula 1: Z1—(R1)m—(R2)n—Z2??(1), wherein R1 is represented by Formula 2: —X1—Ar1—Y1—??(2), wherein X1 and Y1 are each independently selected from the group consisting of O, CO and NR?, in which R? is independently selected from the group consisting of a hydrogen atom, a substituted or unsubstituted C1-C20 alkyl group, and a substituted or unsubstituted C6-C30 aryl group, and Ar1 includes at least one divalent aromatic or alicyclic organic group selected from the group consisting of Formula 3:

Abstract: The invention is to provide an AM device containing a liquid crystal composition that satisfies at least one of characteristics such as a high maximum temperature of a nematic phase, a low minimum temperature of a nematic phase, a small viscosity, a large optical anisotropy, a large dielectric anisotropy, a large specific resistance, a high stability to ultraviolet light and a high stability to heat, or that is suitably balanced regarding at least two of the characteristics, and having a short response time, a large voltage holding ratio, a large contrast ratio, a long service life and so forth, where the liquid crystal display device contains the liquid crystal composition that includes a specific compound having a large dielectric anisotropy as a first component and having positive dielectric anisotropy.

Abstract: Provided is a liquid crystal display device includes: a first substrate (6); a second substrate (7); a liquid crystal layer (LC); a first alignment film (606) placed on the first substrate; a second alignment film (705) placed on the second substrate; and at least one of: a transparent layer (610) contacting the first alignment film on the other side of the liquid crystal layer and being lower in volume resistivity than the first alignment film; and a transparent layer (710) contacting the second alignment film on the other side of the liquid crystal layer and being lower in volume resistivity than the second alignment film, wherein the transparent layer contains polysiloxane expressed by Chemical Formula 1: where R1 and R2 each represent an alkyl group or alkoxy group having 1 to 3 carbon atoms, or a hydroxyl group, and at least 30% of hydroxyl groups are contained.

Abstract: Provided is a liquid crystal composition that satisfies at least one of characteristics such as high maximum temperature of a nematic phase, low minimum temperature of a nematic phase, small viscosity, large optical anisotropy, large dielectric anisotropy, large specific resistance, high stability to ultraviolet light and high stability to heat, or that is suitably balanced between at least two of the characteristics; and provided is an AM device. The liquid crystal composition having a nematic phase includes a three-ring compound having a specific difluoromethyleneoxy bond having large dielectric anisotropy as a first component, a specific three-ring compound having large dielectric anisotropy as a second component, a specific four-ring compound having high maximum temperature as a third component, and a specific two-ring compound having high maximum temperature and small viscosity as a fourth component, and the liquid crystal display device contains this composition.

Abstract: The invention provides a liquid crystal compound having a high stability to heat, light or the like, a wide temperature range of a nematic phase, a small viscosity, a large optical anisotropy and a suitable elastic constant K33, and further having a suitable negative dielectric anisotropy and an excellent compatibility with other liquid crystal compounds.

Abstract: Disclosed is a liquid crystal composition that can satisfy at least one of properties such as a high upper limit temperature of a nematic phase, a low lower limit temperature of a nematic phase, a low viscosity, a proper optical anisotropy, a negatively high dielectric anisotropy, a high specific resistance, a high stability against ultraviolet light, and a high stability against heat, or has a proper balance between at least two of the above properties. The liquid crystal composition comprises a first component of a dicyclic compound which has a negatively high dielectric anisotropy and contains fluorines at least three of lateral positions, a second component of a specific compound having a low viscosity, and a third component of a specific compound having a negatively high dielectric anisotropy and contains a negatively dielectric anisotropy. The liquid crystal display element comprises the composition.

Abstract: A birefringent film which comprises a compound having a proton-accepting group and a compound having a proton-donating group; and a birefringent film which comprises a compound having a proton-accepting group and a proton-donating group. The proton-accepting group and proton-donating group are combined with each other through intermolecular hydrogen bonding.

Abstract: The present invention relates to a light-sensitive compound, a polymer formed by using the compound, and a production method of the compound and polymer. More particularly, the present invention relates to a unit compound that exhibits light-sensitivity with respect to three different wavelengths, a polymer having light-sensitive, which is polymerized by using the unit compound as a monomer, and a production method of the compound and polymer. The light-sensitive compound and the polymer according to the present invention may be usefully applied to an optical film.

Abstract: The present invention relates to thiophene derivatives, to processes and intermediates for the preparation thereof, to the use thereof for optical, electro-optical and electronic purposes, in particular in liquid-crystal (LC) media and LC displays, and to LC media and LC displays comprising same.

Abstract: A depolarizing film of the present invention comprises a film containing at least one liquid crystal compound, wherein the liquid crystal compound comprises a liquid crystal compound (1) that satisfies the relation: 0.05??n?0.5, with the proviso that ?n=ne?no, ne represents an extraordinary-ray refractive index, and no represents an ordinary-ray refractive index, and the film has a haze value of 15% or less and a thickness of 1 ?m to 10 ?m.

Abstract: A smart film structure is provided. It includes a light shuttle film, a heat insulating film structure arranged on one surface of the light shuttle film, and an attached layer arranged on another surface of the light shuttle film. This smart film structure is attached to a transparent object by using the attached layer, to change the transparent state of the transparent object at user's own choice. The transparent object may be insulated against heat by means of the heat insulating film structure, so as to lower indoor temperature and reduce the use of air conditioners with the advantage of energy conservation.

Abstract: The invention is to provide a liquid crystal composition that satisfies at least one of characteristics such as a high maximum temperature of a nematic phase, a low minimum temperature of a nematic phase, a small viscosity, a suitable optical anisotropy, a large negative dielectric anisotropy, a large specific resistance, a high stability to ultraviolet light and a high stability to heat, or that is suitably balanced regarding at least two of the characteristics; and is to provide a AM device that has a short response time, a large voltage holding ratio, a large contrast ratio, a long service life and so forth, wherein the liquid crystal composition has negative dielectric anisotropy and includes a two-ring compound having a large negative dielectric anisotropy and having at least three fluorines or chlorines at the lateral positions as a first component, a specific compound having a large negative dielectric anisotropy as a second component, a specific compound having a small viscosity as a third component,

Abstract: The invention relates to novel calamitic mesogenic compounds which are especially suitable for use in birefringent films with negative optical dispersion, to novel liquid crystal (LC) formulations and polymer films comprising them, and to the use of the compounds, formulations and films in optical, electrooptical, electronic, semiconducting or luminescent components or devices.

Abstract: Disclosed is a negative C-type retardation compensator for a liquid crystal display. The negative C-type retardation compensator for the liquid crystal display includes polyarylate having a thio group or a sulfur oxide group in a polymer main chain thereof. Accordingly, the retardation compensator has an absolute value of negative retardation that is larger in a thickness direction than a retardation compensator which includes polyarylate having no thio group or sulfur oxide group in a polymer main chain thereof even though the retardation compensator having the thio group or sulfur oxide group and the retardation compensator having no thio group or sulfur oxide group are the same as each other in thickness. Thereby, the negative C-type retardation compensator for liquid crystal displays is capable of being desirably applied to the liquid crystal displays.

Abstract: The invention provides a liquid crystal compound having a high stability to heat, light or the like, a nematic phase in a wide temperature range, a small viscosity, a suitable optical anisotropy (especially, a relatively small optical anisotropy), a large elastic constant K33 and a suitable dielectric anisotropy (especially, a relatively large dielectric anisotropy), which is represented by formula (1-1). For example, R1 and R2 are alkyl having 1 to 10 carbons, alkenyl having 2 to 10 carbons or alkoxy having 1 to 9 carbons; the ring A1 and the ring A2 is 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene or 3,5-difluoro-1,4-phenylene; and m and n are 0, 1, 2 or 3, and the sum of m and n is 3.

Abstract: The invention relates to mesogenic tetrahydropyran compounds having at least four rings, of the formula I in which R1, A1, A2, X1, L1, L2, m and n have the meanings indicated in Claim 1, and to a process for the preparation thereof, to the use thereof in liquid-crystalline media, to liquid-crystalline media comprising at least one compound of the formula I, and to electro-optical displays containing a liquid-crystalline medium of this type.

Abstract: To provide a liquid crystal polyester composition which is suited for use as a material for forming a liquid crystal polyester film having excellent thermal conductivity. Also, an excellent electronic circuit board is provided by using an insulating film obtained from the liquid crystal polyester composition. The liquid crystal polyester composition of the present invention is composed of a liquid crystal polyester, a solvent and a thermally conductive filler. The thermally conductive filler is contained in the amount of 50 to 90 volume % based on the total amount of the liquid crystal polyester and the thermally conductive filler, and the thermally conductive filler contains 0 to 20 volume % of a first thermally conductive filler having a volume average particle diameter of 0.1 ?m or more and less than 1.0 ?m, 5 to 40 volume % of a second thermally conductive filler having a volume average particle diameter of 1.0 ?m or more and less than 5.

Abstract: Provided are a liquid crystal composition containing, as a first component, a polymerizable compound represented by general formula (I): and a liquid crystal display element using the liquid crystal composition.

Abstract: The invention provides a compound represented by formula (1). In the formula (1), R1 is hydrogen, methyl or ethyl; X1 is a single bond, —O— or —OCO—; X2 is a single bond, —O—, —COO— or —OCO—; A1 and A2 are each independently a divalent aromatic ring or a divalent cyclohexane ring, and in these rings, arbitrary hydrogen may be replaced by halogen, alkyl having 1 to 3 carbons or halogenated alkyl having 1 to 3 carbons; Z1 is independently a single bond, —O—, —S—, —COO—, —OCO—, —CH2O—, —OCH2—, —CH?CH—COO—, —OCO—CH?CH—, —CH2CH2—COO—, —OCO—CH2CH2—, —CON(R)— or —N(R)CO—; R is hydrogen or methyl; Y is a terpenoid residue or a steroid residue; m is an integer from 0 to 20; and n is an integer from 0 to 3.

Abstract: A polymerizable liquid crystal compound shown by the following formula, a polymerizable liquid crystal composition that includes the polymerizable liquid crystal compound and a chiral compound polymerizable with the polymerizable liquid crystal compound, a liquid crystalline polymer obtained by polymerizing the polymerizable liquid crystal compound or the polymerizable liquid crystal composition, and an optically anisotropic article that includes the liquid crystalline polymer, are disclosed.

Abstract: A liquid crystal composition is provided that satisfies at least one characteristic among the characteristics such as a high maximum temperature of a nematic phase, a low minimum temperature of a nematic phase, a low viscosity, a large optical anisotropy, a large dielectric anisotropy, a large specific resistance, a high stability to ultraviolet light and a high stability to heat, or is properly balanced regarding at least two characteristics. An AM device is provided that has a short response time, a large voltage holding ratio, a large contrast ratio, a long service life, and so forth. The liquid crystal composition has a nematic phase, wherein the first component contains a specific five rings compound having a large optical anisotropy and a large dielectric anisotropy, the second component contains a specific compound having a low viscosity. The liquid crystal display device contains the liquid crystal composition having a nematic phase and the composition thereof.

Abstract: A reactive silicon dioxide compound, wherein the formula of the reactive silicon dioxide compound is shown as Formula (I): where each R is a reactive group shown as Formula (II) or Formula (III), independently: and where R1, R2 and R3 include H or CH3, independently, n1 is an integer of about 1-6 and n2 is an integer of about 0-4. An optical protective film containing the reactive silicon dioxide compound is also provided.

Abstract: Embodiments of the invention provide a negative light sensitive resin composition, a color filter and a liquid crystal display device. The negative light sensitive resin composition comprises: an alkaline soluble resin, which is a terpolymer, or a derivative of the terpolymer, made from the following three monomers: styrene, ?-pinene, and a carboxylic acid or anhydride containing an unsaturated double bond; a light sensitive resin containing ethylene unsaturated double bonds, which is in a mass ratio of 0.1 to 1.2:1 to the alkaline soluble resin; a photoinitiator, which is in a mass ratio of 0.0001 to 0.001:1 to the composition; a modifying adjuvant, which is in a mass ratio of 0.001 to 0.01:1 to the solid fraction in the composition; and a solvent, which is in a mass ratio of 2 to 20:1 to the solid fraction in the composition. The color filter and the liquid crystal display device comprise a light filter structure formed by the curing of the aforementioned negative light sensitive resin composition.

Abstract: The invention is directed to compositions of display cell structure and electrode protecting layers for improving the performance of display devices. The composition comprises a polar oligomeric or polymeric material having a glass transition temperature below about 100° C., and the resulting display cells or electrode protecting layer have an average crosslinking density of below about 1 crosslink point per 80 Dalton molecular weight.

Abstract: Provided are a liquid crystal composition containing, as a first component, a polymerizable compound represented by general formula (I): R11—S11-L11-(M11-L12)m-M12-L13-(M13-L14)n-Z11??(I) and a liquid crystal display element using the liquid crystal composition.

Abstract: An object is to provide a liquid crystal composition which exhibits a blue phase in a wide temperature range. Another object is to provide a liquid crystal composition which exhibits a blue phase, with which high contrast can be provided, in a liquid crystal display device. A liquid crystal composition which exhibits a blue phase includes: a nematic liquid crystal including a compound represented by a structural formula (100) (PPEP-5FCNF (abbreviation)); and a chiral agent. In a liquid crystal display device, a liquid crystal layer is formed using the liquid crystal composition including a nematic liquid crystal including a compound represented by a structural formula (100) (PPEP-5FCNF (abbreviation)) and a chiral agent, and the liquid crystal composition exhibits a blue phase.

Abstract: Diamine compounds, which in particular are useful as precursors for the production of liquid crystal alignment layers, are represented by the general formula I: wherein A1 represents an organic group of 1 to 40 carbon atoms; A2 represents a hydrogen atom or an organic group of 1 to 40 carbon atoms.

Abstract: The subject is to provide a liquid crystal that has a high stability to heat, light and so forth, a wide temperature range of a nematic phase, a small viscosity, a large optical anisotropy and a suitable elastic constant K33, and further has a large negative dielectric anisotropy and an excellent compatibility with any other liquid crystal compound. The invention provides the compound (1): wherein, for example, R1 and R2 are hydrogen, alkyl having 1 to 10 carbons, alkenyl having 2 to 10 carbons, alkoxy having 1 to 9 carbons, alkoxyalkyl having 2 to 9 carbons or alkenyloxy having 2 to 9 carbons; when one of the ring A1, the ring A2 and the ring A3 is 1,4-phenylene or 2,3-difluoro-1,4-phenylene, the other two are 1,4-cyclohexylene or 1,4-cyclohexenylene; and Z1 is a single bond, —(CH2)2—, —CH2O—, —OCH2—, —COO— or —OCO—.

Abstract: Provided are a liquid crystal composition containing, as a first component, a polymerizable compound represented by general formula (I): (Z11)m11-M11-(L11-M12)n11-COO-(M13-L12)n12-M14-(Z12)m12??(I) and a liquid crystal display element using the liquid crystal composition.

Abstract: A liquid crystalline compound shown by the following formula (I). wherein R1 to R13 represent a hydrogen atom, a fluorine atom, a methyl group, a trifluoromethoxy group, or a cyano group, X represents —O—, —O—CO—, or the like, n is 0 or 1, and R14 represents -A-CO—CH?CH2, wherein A is a linking group. The liquid crystalline compound has a higher liquid crystal phase upper limit temperature, is chemically stable, can be inexpensively produced, and exhibits a large selective reflection wavelength zone ?? (a large ?n). A liquid crystalline composition comprising the liquid crystalline compounds, an optical film having a liquid crystal layer formed using the liquid crystalline composition, and an optical laminate comprising a substrate, an alignment film formed on the substrate, a liquid crystal layer formed using the liquid crystalline composition on the alignment film are also disclosed.

Abstract: The instant invention relates to mesogenic systems comprising a) a polymeric component, component A, obtained or obtainable from polymerisation of a precursor comprising one or more mesogenic mono-reactive compounds, one or more di-reactive compounds, which optionally are also mesogenic compounds and optionally a photo-initiator and a low molecular weight component, component B, comprising one or more mono-reactive, mesogenic compounds, one or more mesogenic compounds and one or more chiral dopants, exhibiting a Blue Phase, as well as to the use of these systems in deices and to these devices.

Abstract: The present invention relates to dielectrically positive liquid-crystalline media comprising one or more compounds of the formula I in which the parameters have the meaning indicated in the specification, and optionally one or more compounds selected from the group of the compounds of the formulae II and III in which the parameters have the meaning indicated in the specification, and optionally one or more compounds of the formula IV in which the parameters have the meaning indicated in the specification, and to liquid-crystal displays containing these media, especially to active-matrix displays and in particular to TN, IPS and FFS displays.

Abstract: The invention provides a liquid crystal composition that includes a specific compound having a negatively large dielectric anisotropy as a first component and a specific compound having a negatively large dielectric anisotropy as a second component, that optionally includes a specific compound having a high maximum temperature or a small viscosity as a third component and a specific compound having a negatively large dielectric anisotropy as a fourth component, and that has negative dielectric anisotropy, and provides a liquid crystal display device containing this composition.

Abstract: The present invention relates to dielectrically positive liquid-crystalline media comprising a dielectrically neutral or slightly positive component, component A, comprising one or more dielectrically neutral or slightly positive compounds of the formula I in which the parameters have the meaning indicated in the specification, and a dielectrically positive component, component B, comprising one or more dielectrically positive compounds, and optionally a second dielectrically neutral component, component C, and to liquid-crystal displays containing these media, especially active-matrix displays and in particular TN, IPS and FFS displays.

Abstract: The invention provides a liquid crystal compound which has stability to heat, light and so forth, a nematic phase in a wide temperature range, a small viscosity, a large optical anisotropy, and a suitable elastic constant K33, and further has a suitable and negative dielectric anisotropy and an excellent compatibility with other liquid crystal compounds. Moreover, the invention provides a liquid crystal composition comprising this liquid crystal compound and a liquid crystal display device containing this liquid crystal composition. A liquid crystal compound represented by formula (a): for example, R1 and R2 are alkyl having 1 to 10 carbons, alkenyl having 2 to 10 carbons or alkoxy having 1 to 9 carbons; ring A1 and ring A2 are 1,4-phenylene or trans-1,4-cyclohexylene; L1 and L2 are hydrogen or fluorine, and at least one of L1 and L2 is fluorine; and Z1 and Z2 are a single bond, —(CH2)2—, —CH?CH—, —CH2O— or —OCH2—.