There is provided an element which has large dielectric anisotropy and low dielectric loss in a high frequency range, has high reliability, and is used for phase control of an electromagnetic wave signal with a frequency of 1 MHz to 400 THz. An element in which a liquid crystal composition contains a compound represented by the following Formula (1) and has a refractive index anisotropy of 0.30 or more at a wavelength of 589 nm, and a polyimide alignment film contains 10% or more of a repeating unit represented by the following Formula (2) with respect to all repeating units:

##STR00001##

The problem is to provide a polymerizable compound having suitable polymerization reactivity, a high conversion ratio, low polymerization starting temperature, and high solubility in a liquid crystal composition; a liquid crystal composition containing the compound; and a liquid crystal display device including the composition.

A means thereof includes a compound represented by formula (1) and a liquid crystal composition containing the compound.

##STR00001##

In formula (1), R.sup.1, R.sup.2 and R.sup.3 are independently alkyl or the like; n is 0 or the like; ring A.sup.1 is phenyl or the like, and ring A.sup.2 and ring A.sup.3 are independently 1,4-phenylene or the like; Z.sup.1 and Z.sup.2 are independently a single bond or the like; Sp.sup.1 to Sp.sup.4 are a single bond or the like; a is 1 or the like; c, d and e are independently 0 or 1, and a sum of c, d and e is 1 or the like; and P.sup.1 to P.sup.4 are a polymerizable group, and at least one of P.sup.1 to P.sup.4 is a polymerizable group represented by formula (P-1).

##STR00002##

A photoreactive liquid crystal composition containing (A) a photoreactive polymer liquid crystal which includes a photoreactive side chain in which at least one type of reaction selected from (A-1) photocrosslinking and (A-2) photoisomerization occurs, and (B) a low molecular weight liquid crystal. An optical element or display element is formed having a liquid crystal cell including the photoreactive liquid crystal composition.

An object of the present invention is to provide a composition that realizes high n, has a wide liquid crystal phase temperature range, small viscosity, excellent low-temperature solubility, and high resistivity and voltage holding ratio, and is stable against heat and light, and to provide a liquid crystal composition having an excellent lens effect and excellent chemical stability using the composition, and a liquid crystal display device and a liquid crystal lens that use the liquid crystal composition. The present invention provides a liquid crystal composition that contains one or two or more compounds represented by general formula (i) and one or two or more compounds represented by general formula (ii), a liquid crystal display device using the liquid crystal composition, a liquid crystal lens using the liquid crystal composition, and a birefringence lens for stereoscopic image display using the liquid crystal composition.

The present invention relates to compounds of formula M

##STR00001##

in which R.sup.M has the meaning indicated in claim 1, to liquid crystal mixture comprising the same, to the use of these liquid-crystal media, in particular in components for high-frequency technology, and to components of this type which contain media according to the invention, and to the production and use of these components. The components according to the invention are suitable, in particular, as phase shifters in the microwave and millimetre wave region, for microwave and millimetre wave array antennae and very particularly for so-called tunable reflectarrays.

The disclosure provides a liquid crystal composition having favorable characteristics and excellent characteristic balance as a material used for an element used for phase control of an electromagnetic wave signal having a frequency of 1 MHz to 400 THz. A liquid crystal composition which is used for phase control of an electromagnetic wave signal having a frequency of 1 MHz to 400 THz, and which includes a compound selected from the group represented by Formula (1),

##STR00001## in Formula (1), the ring A.sup.0 to the ring A.sup.4 are each independently 1,4-phenylene and the like; Z.sup.0 to Z.sup.3 are each independently a single bond or CF.sub.2O, where CF.sub.2O is one or less in Z.sup.0 to Z.sup.3; p is 0 or 1; and R.sup.1 is alkyl having 1 to 12 carbon atoms and the like, and R.sup.11 is CN and the like.

Provided are liquid crystal compounds and mixtures incorporating the same. The liquid crystal compounds of the invention generally comprise a cyclopentane group and at least two other rings. In one embodiment, the liquid crystal compounds of the invention comprise a cyclopentane group and at least two other rings, one of which is a fused ring system.

The present invention relates to thermotropic ionic liquid crystal molecules of general formula (I)

##STR00001##

With E.sub.1 and E.sub.2, which may be identical or different, representing, independently of one another, a linear, saturated and unsubstituted C.sub.10 to C.sub.14 hydrocarbon-based radical, A.sup.x representing a sulfonate anion or a sulfonylimide anion of formula SO.sub.2N.sup.SO.sub.2C.sub.yF.sub.2y+1 with y being an integer ranging from 0 to 2 and C.sup.x+ a sodium, lithium or potassium ion, most particularly advantageous for their conductivity performance qualities as an electrolyte in particular for lithium batteries.

The present application relates to mixtures which have liquid-crystalline properties. The application furthermore relates to the use of the mixtures in devices which regulate the transmission of light through an area element.

The invention relates to compounds of the formula I, ##STR00001##
in which R, A, Z, m, L.sup.1, L.sup.2, L.sup.3 and X have the meanings indicated in Claim 1, to a process for the preparation thereof, and 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.