Provided is a liquid crystal composition satisfying at least one or having suitable balance regarding at least two of characteristics such as high maximum or low minimum temperature of a nematic phase, large optical anisotropy, large positive dielectric anisotropy and high stability to ultraviolet light, and a liquid crystal display device including such a composition, particularly an encapsulated liquid crystal display device, and a liquid crystal display device serving as a constituent of 3D lenses. The liquid crystal composition contains a specific compound having large optical anisotropy as a first component, and a specific compound having large optical anisotropy and large positive dielectric anisotropy as a second component; a specific compound having large positive dielectric anisotropy as a third component; and a specific compound having large optical anisotropy and further having high maximum or low minimum temperature as a fourth component, and the liquid crystal display device includes the composition.

The present invention relates to liquid-crystalline media comprising—one or more compounds of formulae CC and/or CP and—one or more compounds selected from the group of compounds of formulae (I), (II) and (III), in which the parameters have the meaning indicated in Claim 1, and to components comprising these media for high-frequency technology, in particular phase shifters and microwave array antennas.

##STR00001##

An object of the present invention is to provide a composition that has positive Δε, exhibits a liquid crystal phase over a wide temperature range, has low viscosity, excellent solubility at low temperatures, and high resistivity and voltage holding ratio, and is stable against heat and light. By using this composition, IPS or TN liquid crystal display devices and the like that have excellent display quality and suppress display failures such as image-sticking and drop marks are provided in high yield. Provided is a composition that contains at least one selected from the group consisting of compounds represented by general formulae (i) and (ii) and at least one compound represented by general formula (iii). Also provided is a liquid crystal display device that uses the composition and an IPS or FFS device that uses the composition.

The liquid crystal composition has the nematic phase and contains a specific compound having large positive dielectric anisotropy as a first component, and a specific compound having small viscosity as a second component, and may contain a specific compound having large positive dielectric anisotropy as a third component, a specific compound having a high maximum temperature or large positive dielectric anisotropy as a fourth component, or a specific compound having negative dielectric anisotropy as a fifth component, and a liquid crystal display device includes the composition.

Shown is a liquid crystal composition satisfying at least one of characteristics such as high maximum temperature, low minimum temperature, small viscosity, suitable optical anisotropy, large dielectric anisotropy and small frequency dependence, or has a suitable balance regarding at least two of the characteristics, and an AM device including the composition. The liquid crystal composition contains a specific compound having large positive dielectric anisotropy as a first component, and a specific compound having small viscosity as a second component, and may contain a specific compound having high maximum temperature or small viscosity as a third component, a specific compound having positive dielectric anisotropy as a fourth component or a specific compound having negative dielectric anisotropy as a fifth component.

The present invention relates to liquid-crystalline media comprising one or more compounds of formula DFS ##STR00001##
in which the groups and parameters occurring have the meanings indicated in claim 1, to high-frequency components comprising same, especially microwave components for high-frequency devices, such as devices for shifting the phase of microwaves, in particular for microwave phased-array antennas. The present invention further relates to novel mesogenic compounds.

The present invention relates to benzotriazole derivatives selected from the group of compounds of formulae Ia, Ib and Ic as defined in claim 1, to mesogenic media comprising the compounds of formulae Ia, Ib and Ic, and to the use of these compounds and mesogenic media in optical, electronic and electro-optical applications, in particular in devices for regulating the passage of energy from an outside space into an inside space, for example in windows.

A liquid-crystalline medium, preferably having a nematic phase and dielectric anisotropy of 0.5 or more, which has one or more compounds of formula S

##STR00001## in which

##STR00002##

denotes

##STR00003##

and the other parameters have the meanings given in the text. Also, the use of the medium 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 use of the compounds of formula S for the improvement of the transmission and/or response times of a liquid-crystalline medium which comprises one or more additional mesogenic compounds.

A liquid crystal display device comprises a first substrate, a second substrate which faces the first substrate, an electrode part which is provided on at least one of the first substrate and the second substrate, and a liquid crystal layer which comprises a liquid crystal composition and is provided between the first substrate and the second substrate. The liquid crystal composition includes a liquid crystal compound of Formula 1. ##STR00001##
wherein R.sub.1, R.sub.2, A.sub.11, A.sub.12, A.sub.13, A.sub.21, A.sub.22, Z.sub.11, Z.sub.12, Z.sub.13, Z.sub.21, Z.sub.22, a, b, c, d, and e are as described herein.

A problem is to provide a liquid crystal compound satisfying at least one physical property such as high stability to heat and light, a high clearing point (or high maximum temperature), a low minimum temperature of a liquid crystal phase, small viscosity, suitable optical anisotropy, large dielectric anisotropy, a suitable elastic constant and excellent compatibility with other liquid crystal compounds, a liquid crystal composition containing the compound and a liquid crystal display device including the composition. A solution is a compound represented by formula (1). ##STR00001## In which, R.sup.1 is alkyl having 1 to 10 carbons or the like; Z.sup.1, Z.sup.2 and Z.sup.3 are independently a single bond, —COO—, —OCH.sub.2—, —CF.sub.2O— or the like, and at least one of Z.sup.1, Z.sup.2 and Z.sup.3 is —CF.sub.2O—; X.sup.1 is hydrogen, fluorine, —CF.sub.3 or —OCF.sub.3; and L.sup.1, L.sup.2, L.sup.3 and L.sup.4 are independently hydrogen, fluorine or chlorine.