An object of the present invention is to provide a liquid crystal composition suitable for producing liquid crystal display elements which reduces the risk of the formation of droplet traces during production and allows a liquid crystal material to be ejected at a constant rate during an ODF process without deteriorating the properties of the liquid crystal display element, such as dielectric anisotropy, viscosity, nematic-phase upper-limit temperature, nematic-phase stability at a low temperature, and γ.sub.1, and the image sticking resistance of the display element, and a liquid crystal display element including the liquid crystal composition. Provided are a liquid crystal composition having a negative dielectric anisotropy, the liquid crystal composition including one or more compounds represented by General Formula (I), one or more compounds represented by General Formula (II), and the compound represented by Formula (IIIb-1) and a liquid crystal display element including the liquid crystal composition.

The invention relates to a liquid-crystalline medium having negative dielectric anisotropy comprising one or more compounds of formula I ##STR00001##
and
one or more compounds selected from the group of the compounds of the formulae IIA, IIB and IIC, ##STR00002##
wherein the groups and parameters have the meanings indicated in claim 1, to a guest-host liquid crystal medium derived therefrom comprising one or more dichroic dyes and the use of said medium in devices such as light shutters, switchable windows, switchable mirrors and guest-host displays. The invention further relates to devices containing the liquid crystalline medium according to the invention.

A positive dielectric anisotropic liquid crystal composition includes one or more compounds of formula I and one or more compounds of formula II: ##STR00001##
wherein R1 represents cyclopropyl, cyclobutyl or cyclopentyl, R2, R3 and R4 are as defined in the specification, and a liquid crystal display device. The liquid crystal composition has positive dielectric properties, a high charge retention ratio, a low rotary viscosity, a fast response time, and especially a high transmittance, and is suitable for manufacturing a TFT-LCD with a high transmittance and a fast response.

Aromatic isothiocyanates of formula C

##STR00001##

liquid-crystalline media comprising one or more compounds of formula C, and high-frequency components comprising these media, especially microwave components for high-frequency devices, such as devices for shifting the phase of microwaves, tunable filters, tunable metamaterial structures, and electronic beam steering antennas, e.g. phased array antennas.

The invention relates to a liquid crystal device comprising at least two opposing transparent substrates, at least one liquid crystal switching layer sandwiched between said opposing substrates comprising one or more polymerised photoreactive mesogens of formula I,

R.sup.11-Sp.sup.11-X.sup.11[-A-Z].sub.o-A.sup.11-CY.sup.11═CY.sup.12[—C═O].sub.x[—O].sub.y-A[-Z-A].sub.p—X.sup.21-Sp.sup.21-R.sup.21  I

wherein R.sup.11, R.sup.21, A.sup.11, A, Z, X.sup.11, X.sup.21, Y.sup.11, Y.sup.12, Sp.sup.11, Sp.sup.21, o, p, x and y have one of the meanings as given in claim 1, and one or more nematogenic compounds, an electrode structure provided on one or both of the opposing substrates, wherein one or more of said substrates are additionally provided with an optical grating or a lens structure adjacent to the LC switching layer. The invention is further related to a method of production of said liquid crystal device, to the use of said Liquid Crystal device in various types of optical and electro-optical devices, and to electro-optical devices comprising the liquid crystal device.

The disclosure belongs to the technical field of liquid crystal materials, and specifically relates to a polymerizable compound, a preparation method therefor, and the use thereof. The polymerizable compound has a structure as shown in general formula I. Compared with the existing polymerizable RM, the polymerizable compound has the advantages of a good solubility, a faster polymerization rate, a more complete extent of polymerization, and less residues, thereby improving the problem of poor display to a great extent.

##STR00001##

A liquid crystal mixture applied in light modulating devices includes at least one compound selected from the group of compounds of formula I, at least one compound selected from the group of compounds of formula II and/or formula III, and at least one chiral compound. A light modulating device includes the liquid crystal mixture, where the light modulating device has reduced haze in the transparent state while increased opacity in the light scattering state.
R.sub.1-MG.sub.1-X-MG.sub.2-R.sub.2  I ##STR00001##

To provide a liquid crystal composition having at least one or a suitable balance regarding two of characteristics such as high maximum or low minimum temperature of a nematic phase, small viscosity, suitable optical anisotropy, large dielectric anisotropy, large specific resistance, high stability to ultraviolet light or heat and a large elastic constant; and an AM device including the composition and having a short response time, a large voltage holding ratio, low threshold voltage, a large contrast ratio, a long service life and so forth. The liquid crystal composition contains a quencher as an additive component and a specific compound having large positive dielectric anisotropy as a first component, and a liquid crystal display device includes the composition. The composition may contain a specific compound having high maximum temperature or small viscosity as a second component, or a specific compound having negative dielectric anisotropy as a third component.

Provided is a polar compound having high chemical stability, high capability of aligning liquid crystal molecules, high solubility in a liquid crystal composition, and a large voltage holding ratio when used in a liquid crystal display device. The compound is represented by formula (1):

##STR00001##

in which, for example, R.sup.1 is alkyl having 1 to 15 carbons; MES is a mesogen group having at least one ring; Sp.sup.1 is a single bond or alkylene having 1 to 10 carbons; M.sup.1 and M.sup.2 are hydrogen; and R.sup.2 is a group represented by formulas (1a) to (1c):

##STR00002##

in which, Sp.sup.2 and Sp.sup.a are a single bond or alkylene having 1 to 10 carbons; S.sup.1 is >CH—; S.sup.2 is >C<; and X.sup.1 is —OH.

A polar compound has a high chemical stability, high ability to align liquid crystal molecules and high solubility in a liquid crystal composition, and causes no decrease of liquid crystallinity of the liquid crystal composition, a liquid crystal composition contains the compound, and a liquid crystal display device includes the composition. The compound is represented by formula (1), the composition contains the compound, and the liquid crystal display device uses the composition. ##STR00001## In formula (1), R.sup.1 is alkyl having 3 to 15 carbons, alkenyl having 4 to 15 carbons or the like; a is an integer from 2 to 12; and R.sup.2 is a group represented by formula (1a), formula (1b) or formula (1c). ##STR00002## In the formulas, S.sup.1 and S.sup.2 are independently a single bond, alkylene having 1 to 10 carbons; S.sup.3 is >CH— or >N—; S.sup.4 is >C< or >Si<; and X.sup.1 is —OH, —NH.sub.2 or the like.