A compound is represented by general formula (I), a liquid-crystal composition contains this compound, and devices are made using this liquid-crystal composition. Having a large refractive-index anisotropy Δn and a sufficiently high Tni, highly compatible with liquid-crystal compositions, and exhibiting a high dielectric anisotropy in the radio frequency range, the compound is a useful material for RF phase shifters, phased-array antennae, image recognition devices, distance meters, liquid-crystal displays, liquid-crystal lenses, and birefringent lenses for 3D image display, among other devices. ##STR00001##

The present invention relates to a cholesteric liquid crystalline (LC) medium for a Polymer-Network Liquid Crystalline (PNLC) light modulation element, to a method of its production and to the use of such cholesteric LC media in PNLC light modulation elements. Furthermore, the present invention relates to PNLC light modulation elements, as such, to a method of their production, to the use of such light modulation elements in optic or electro optic devices, in particular in LC displays, and to optic or electro optic devices comprising such light modulation elements according to the present invention.

A compound that helps achieve a high voltage holding ratio (VHR) of a liquid crystal composition, a liquid crystal composition that contains this compound, and a liquid crystal display element made with this liquid crystal composition. More specifically, a compound represented by general formula (Y), which has polymerizable groups and polar group(s). A liquid crystal composition containing one or two or more compounds represented by general formula (Y), each of which has polymerizable groups and polar group(s). A liquid crystal display element made with a liquid crystal composition that contains one or two or more compounds represented by general formula (Y), each of which has polymerizable groups and polar group(s).

A LC lens and a liquid-crystal medium used in said LC lens, wherein the medium contains one or more compounds of each of formulae I and II ##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 III. The liquid crystal composition has a higher optical anisotropy, the relatively large elastic constants K.sub.11 and K.sub.33 while maintaining a relatively high clearing point, an appropriate dielectric anisotropy and a better low-temperature intersolubility. A liquid crystal display device which includes the liquid crystal composition has advantages of a fast response, a high contrast and a wide temperature range, thereby having a good display effect and a large range of applicability. ##STR00001##

The invention relates to a compound of formula I,

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wherein R.sup.11, R.sup.21, A.sup.11, A, Z, X.sup.11, X.sup.21, Y.sup.11, Y.sup.12, Sp.sup.11, Sp.sup.21, o and p have one of the meanings as given in claim 1. The invention further relates to method of production of a compound of formula I, to the use of said compounds in LC media and to LC media comprising one or more compounds of formula I. Further, the invention relates to a method of production of such LC media, to the use of such media in LC devices, and to LC device comprising a LC medium according to the present invention. The present invention further relates to a process for the fabrication such liquid crystal display and to the use of the liquid crystal mixtures according to the invention for the fabrication of such liquid crystal display.

The invention relates to a liquid-crystalline medium having a nematic phase comprising one or more compounds of formula X

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wherein the parameters have the meaning given in the text,
to the use thereof in an electro-optical display, particularly in an active-matrix display based on the IPS or FFS effect, to displays of this type which contain a liquid-crystalline medium of this type and to the use of the compounds of formula X for improvement of the transmission and/or response times of a liquid-crystalline medium which comprises one or more additional mesogenic compounds, as well as to certain compounds of formula X, as specified in the text.

A liquid-crystalline medium which comprises at least one compound selected from the group of compounds of the formulae IA to IH,

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in which Z.sup.1 denotes a single bond, —CH.sub.2CH.sub.2—, —CH═CH—, —CH.sub.2O—, —OCH.sub.2—, —CF.sub.2O—, —OCF.sub.2—, —COO—, —OCO—, —C.sub.2F.sub.4—, —(CH.sub.2).sub.4—, —CHFCHF—, —CF.sub.2CH.sub.2—, —CH.sub.2CF.sub.2—, —C≡C—, —CF═CF—, —CH═CHCHO— or —CH.sub.2CF.sub.2O—,
and the use thereof for an active-matrix display, in particular based on the VA, PSA, PS-VA, PALC, FFS, PS-FFS, SA-VA, PS-IPS or IPS effect.

A liquid crystal composition contains: at least one compound of general formula I and at least one polymerizable compound of general formula II. Such a liquid crystal composition has a suitable optical anisotropy, a suitable dielectric anisotropy, and a better pretilt angle consistency while maintaining a relatively high clearing point, and the drop mura is good. When the liquid crystal composition is applied to a PSA liquid crystal display, the liquid crystal composition has an excellent display effect. ##STR00001##

Methods for monitoring catalytic chemical reactions are provided. Such a method may comprise (a) exposing a solid surface to conditions to induce a chemical reaction of reactants at an interface formed between the solid surface and a liquid crystal, wherein the solid surface catalyzes the chemical reaction and the liquid crystal is characterized by an anchoring orientation that changes during the chemical reaction; and (b) measuring the anchoring orientation of the liquid crystal at one or more time points and at one or more locations on the solid surface during step (a). Systems for carrying out the methods are also provided.