Liquid-crystalline media comprising one or more compounds of formula T

##STR00001##

as defined in claim 1, 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-crystalline medium, in particular based on a mixture of polar compounds, and to the use thereof for an active-matrix display, in particular based on the VA, SA-VA, IPS, PS-IPS, FFS, PS-FFS, UB-FFS or PS-UB-FFS effect.

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##

A liquid crystal cell in which antenna units are arranged includes a TFT substrate, a slot substrate, and a liquid crystal layer. The TFT substrate includes a first dielectric substrate, TFTs supported by the first dielectric substrate and patch electrodes electrically connected to the TFTs, and a first alignment film covering a groove part between the adjacent patch electrodes. The slot substrate includes a second dielectric substrate, a slot electrode including slots and supported by the second dielectric substrate, and a second alignment film covering the slot electrode. The liquid crystal layer sandwiched between the TFT substrate and the slot substrate. The liquid crystal layer includes a liquid crystal material having a lower limit temperature of a nematic phase of the liquid crystal material of 32 C. or lower and an upper limit temperature of the nematic phase of the liquid crystal material of 110 C. or higher.

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 device using a liquid crystal medium exhibiting an optically isotropic liquid crystal phase, particularly, a blue phase liquid crystal medium for polarized light control application, in which reduction of an effective dielectric constant in a high frequency region is suppressed. A liquid crystal composition contains achiral component T, and has a liquid crystal phase optically exhibiting isotropy, in which achiral component T contains at least one compound selected from the group of compounds represented by formula (1) as a first component, at least one compound selected from the group of compounds represented by formula (2) and formula (3) as a second component, and is used for optical switching for controlling retardation by electric field-induced birefringence.

A liquid-crystalline medium, preferably having a nematic phase and exhibiting a dielectric anisotropy of 0.5 or more, which contains compounds of formula B and formula S ##STR00001## in which ##STR00002##
denotes ##STR00003##
denotes ##STR00004##
the use thereof in an electro-optical display, particularly in an active-matrix display based on the IPS or FFS effect, displays of this type which contain a liquid-crystalline medium of this type, and the use of the compounds of formula S for the improvement of the transmission and/or response times of a liquid-crystalline medium which contains one or more additional mesogenic compounds.

Provided is a liquid crystal compound containing 2,3,4-trisubstituted benzene, a liquid crystal composition thereof, and a liquid crystal display element or a liquid crystal display comprising the liquid crystal compound or the liquid crystal composition, wherein the liquid crystal composition has a lower viscosity, can achieve a quick response, and further has a moderate dielectric anisotropy , a moderate optical anisotropy n, and high stability to heat and light. The liquid crystal display element or liquid crystal display comprising the liquid crystal composition has the properties of a wider nematic phase temperature range, an appropriate birefringence anisotropy, a very high electrical resistivity, a good ultraviolet resistant property, a high charge retention rate, a low vapor pressure etc., and particularly, the liquid crystal compound or the liquid crystal composition has the advantage of a high light transmittance.

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.

There is provided a liquid crystal composition which has favorable characteristics and excellent characteristic balance as a material for an element used for phase control of an electromagnetic wave signal with a frequency of 1 MHz to 400 THz. A liquid crystal composition which contains at least one compound selected from the group consisting of compounds represented by Formula (1), and is used for phase control of an electromagnetic wave signal with a frequency of 1 MHz to 400 THz:

##STR00001##