The present invention relates to heteroaromatic isothiocyanates of formula N

##STR00001##

as defined in claim 1, to liquid-crystalline media comprising one or more compounds of formula N and to 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 present invention relates to heteroaromatic isothiocyanates of formula N

##STR00001##

as defined in claim 1, to liquid-crystalline media comprising one or more compounds of formula N and to 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.

A curved liquid crystal display device, includes: a first bent substrate; a second bent substrate disposed facing the first bent substrate; a liquid crystal layer disposed between the first bent substrate and the second bent substrate, the liquid crystal layer including first liquid crystal molecules disposed adjacent to the first bent substrate and second liquid crystal molecules disposed adjacent to the second bent substrate; a first alignment inducing layer disposed between the first bent substrate and the liquid crystal layer; and a second alignment inducing layer disposed between the second bent substrate and the liquid crystal layer, wherein one of the first alignment inducing layer and the second alignment inducing layer includes a polymerized reactive mesogen, and the remaining alignment inducing layer includes polyimide.

A liquid crystal composition that satisfies a plurality of characteristics in characteristics such as a high maximum temperature of a nematic phase, a low minimum temperature of the nematic phase, small viscosity, large optical anisotropy, large dielectric anisotropy (1 kHz and 20 GHz), large specific resistance, high stability to ultraviolet light and high stability to heat, and that can be used in the form of a millimeter wave phase or microwave phase antenna.

The liquid crystal composition contains at least two specific compounds having the large optical anisotropy and the large dielectric anisotropy as a first component, and a specific compound having a wide nematic phase and capable of adjusting suitable optical anisotropy as a second component, and may contain such a component compound that can finely control the characteristics of the composition.

Provided are a compound represented by general formula (I), a liquid crystal composition that uses the compound, and a liquid crystal display device that uses the liquid crystal composition. Adding the compound represented by general formula (I) to a liquid crystal composition can prevent degradation of the liquid crystal composition by light, heat, etc. The compound represented by general formula (I) dissolves well in the liquid crystal composition. Thus, when the compound represented by general formula (I) is used, a liquid crystal composition having both low viscosity () and high reliability can be prepared, and a high-speed response liquid crystal display device can be provided.

To provide a compound having an effect of preventing photodegradation of a liquid crystal composition and high solubility in a liquid crystal composition, a liquid crystal composition containing the compound, and a liquid crystal display element containing the composition.

There are provided a compound represented by M(Z-Q)m, a liquid crystal composition containing the compound, and a liquid crystal display element using the composition. Here, m is 3, 4, or 5; M is a trivalent, tetravalent, or pentavalent cyclic group, an organic group, or a group constituted by trivalent nitrogen; Z is a single bond, O, COO, or OCO; and Q is a monovalent group represented by Formula (Q-1):

##STR00001## in Formula (Q-1), R.sup.a is a hydrogen atom, O, OII, an alkyl group, or an alkenyl group, a terminal group (CH.sub.3) is optionally substituted with NIIR.sup.2 or NR.sup.3R.sup.4, and here R.sup.3 and R.sup.4 are an alkyl group.

The present invention provides an optical film exhibiting high alignment and good phase difference development in an oblique direction, and a polarizing plate and an image display device using the same. This optical film of the present invention has a substrate; and a phase difference layer which is provided on the substrate to be adjacent to the substrate, in which the phase difference layer is a layer formed by fixing vertical alignment of a liquid crystal compound having a polymerizable group included in a liquid crystal composition containing the liquid crystal compound and a polymer compound, a difference in ?a value between the polymer compound and the substrate, which is calculated using three-dimensional SP values, is 3 or less, and a content of the polymer compound is less than 10 parts by mass with respect to 100 parts by mass of the liquid crystal compound.

A liquid crystal medium that has stability to heat, light and so forth, a wide temperature range of a liquid crystal phase and significantly large dielectric anisotropy to develop an optically isotropic liquid crystal phase is required. Moreover, various optical devices that can be used in a wide temperature range, and have a short response time, a large contrast ratio and a low drive voltage are required. A liquid crystal composition contains an achiral component T containing at least one compound (1) represented by formula (1) and a chiral agent to develop an optically isotropic liquid crystal phase, wherein in formula (1), R.sup.1 is alkyl having 1 to 12 carbons, L.sup.1, L.sup.2 and L.sup.3 are each independently hydrogen, fluorine or chlorine; and Y.sup.1 is fluorine, CF.sub.3, or OCF.sub.3. ##STR00001##

A compound represented by formula (1), a liquid crystal composition containing the compound, and a liquid crystal display device including the composition.

##STR00001## R is alkyl having 1 to 15 carbons or the like; ring A.sup.1 and ring A.sup.2 are independently 1,4-cyclohexylene, 1,4-phenylene or the like; Z.sup.1 and Z.sup.2 are independently a single bond, COO or the like; Y.sup.1, Y.sup.2 and Y.sup.3 are independently hydrogen, fluorine or chlorine; and m is 0, 1 or 2.

The invention relates to mesogenic media comprising one or more bimesogenic compounds, one or more nematogenic compound, one or more chiral compound and a compound of formula I,
R.sup.11-A.sup.11-(Z.sup.12-A.sup.12).sub.m-AGI
in which, the parameter A.sup.11, A.sup.12, Z.sup.12 and R.sup.11 have one of the meanings as given in claim 1, and to the use of these mesogenic media in liquid crystal devices and in particular in flexoelectric liquid crystal devices, as well as to liquid crystal devices comprising a liquid crystal medium according to the present invention.