As a material used in an element used for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz, a liquid crystal composition is required, which has a high upper limit temperature of a nematic phase, a low lower limit temperature of a nematic phase, large dielectric anisotropy and a small tan δ in a frequency region where the phase control of an electromagnetic wave signal is performed, and stability against heat, and which has an excellent balance of the characteristics. A liquid crystal composition which is used in an element for phase control of an electromagnetic wave signal having any frequency from 1 GHz to 10 THz, the liquid crystal composition containing at least one compound selected from compounds represented by Formula (1) as a first component. ##STR00001##

A component for high-frequency technology or for the microwave range and millimeter wave range of the electromagnetic spectrum. The component contains a liquid-crystal compound of the formula I ##STR00001##
in which the parameters have the respective meanings given in the claims or in the text, or a liquid-crystal medium which itself comprises one or more compounds of this formula I. Also, the corresponding, novel liquid-crystal media, the use and preparation thereof, and the production and use of the components. The components are particularly suitable as phase shifters in the microwave and millimeter wave range, for microwave and millimeter wave array antennae and very particularly for so-called tuneable reflectarrays.

A liquid crystal composition includes at least one compound of general Formula I, at least one compound of general Formula II and at least one compound of general Formula M. The polymerizable liquid crystal composition provides a higher VHR (especially an excellent VHR after UV irradiation), a lower surface roughness of the polymer layer, a faster polymerization rate, a lower residual amount of the polymerizable compound and a better pretilt angle stability, which enables the production of a liquid crystal display device with a better voltage stability and a faster response speed, and can effectively reduce or prevent the occurrences of problems such as “burn-in”, “image sticking”, “Zara Particle” and “uneven display” in the liquid crystal display device. A liquid crystal display includes the liquid crystal composition. ##STR00001##

A liquid crystal composition, which is a material used for an element for electromagnetic wave signal control in a frequency range of 1 GHz to 10 THz, satisfies at least one of characteristics such as a wide temperature range of a nematic phase and a large refractive index anisotropy and a small dielectric loss tangent (tan δ) in the frequency region used for control, and has an excellent balance of characteristics, and an element containing the composition. A liquid crystal composition including: at least one compound selected from the group consisting of compounds represented by Formula (1). For example, R.sup.1 is C1-12 alkyl; Z.sup.11 is a single bond; L.sup.11, L.sup.12, L.sup.13 and L.sup.18 are hydrogen; L.sup.17 is methyl; Y.sup.11 and Y.sup.22 are hydrogen; and a, b, and c are respectively 0, 1, and 0.

##STR00001##

A material used in an element for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz. A liquid crystal composition containing at least one compound selected from a group of compounds represented by Formula (1), at least one compound selected from a group of compounds represented by Formula (2) and at least one compound selected from a group of compounds represented by Formula (3).

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For example, R.sup.1, R.sup.21, R.sup.22, R.sup.31, and R.sup.32 are alkyls having 1 to 12 carbon atoms; a ring A.sup.1 is 1,4-phenylene; Z.sup.11, Z.sup.13, Z.sup.21, Z.sup.23, Z.sup.31, and Z.sup.33 are single bonds; Z.sup.12, Z.sup.22, and Z.sup.32 are —C≡C— or —C≡C—C≡C—; L.sup.13 to L.sup.16, L.sup.21 to L.sup.23, and L.sup.31 to L.sup.36 are hydrogen or fluorine; Y.sup.11 and Y.sup.12 are hydrogen or fluorine; and n.sup.1 is 0.

As a material used in an element used for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz, a liquid crystal composition is required, which has a high upper limit temperature of a nematic phase, a low lower limit temperature of a nematic phase, large dielectric anisotropy and a small tan δ in a frequency region where the phase control of an electromagnetic wave signal is performed, and stability against heat, and which has an excellent balance of the characteristics. A liquid crystal composition which is used in an element for phase control of an electromagnetic wave signal having any frequency from 1 GHz to 10 THz, the liquid crystal composition containing at least one compound selected from compounds represented by Formula (1) as a first component.

##STR00001##

A liquid crystal composition includes at least one compound of general Formula I, at least one compound of general Formula II and at least one compound of general Formula M. The polymerizable liquid crystal composition provides a higher VHR (especially an excellent VHR after UV irradiation), a lower surface roughness of the polymer layer, a faster polymerization rate, a lower residual amount of the polymerizable compound and a better pretilt angle stability, which enables the production of a liquid crystal display device with a better voltage stability and a faster response speed, and can effectively reduce or prevent the occurrences of problems such as “burn-in”, “image sticking”, “Zara Particle” and “uneven display” in the liquid crystal display device. A liquid crystal display includes the liquid crystal composition.

##STR00001##

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:

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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##

A liquid crystal composition, which is a material used for an element for electromagnetic wave signal control in a frequency range of 1 GHz to 10 THz, satisfies at least one of characteristics such as a wide temperature range of a nematic phase and a large refractive index anisotropy and a small dielectric loss tangent (tan ?) in the frequency region used for control, and has an excellent balance of characteristics, and an element containing the composition. A liquid crystal composition including: at least one compound selected from the group consisting of compounds represented by Formula (1). For example, R.sup.1 is C1-12 alkyl; Z.sup.11 is a single bond; L.sup.11, L.sup.12, L.sup.13 and L.sup.18 are hydrogen; L.sup.17 is methyl; Y.sup.11 and Y.sup.22 are hydrogen; and a and c are respectively 0 or 1, b is 1, and a sum of a, b, and c is 2.

##STR00001##