The present invention discloses a liquid crystal composition, comprising: at least a first compound selected from the group consisting of a compound of general Formula I-1, a compound of general Formula I-2, and a combination thereof, and at least a second compound selected from the group consisting of a compound of general Formula II-1, a compound of general Formula II-2, a compound of general Formula II3, a compound of general Formula II-4 and a combination thereof The liquid crystal composition provided in the present invention has the properties of appropriate optical and dielectric anisotropies, high clearing point, existence of a nematic phase over a wide range of temperature, low viscosity and good high-temperature stability. The liquid crystal composition is applicable to a liquid crystal display (LCD) device, to enable the LCD device to have such properties as short response time, excellent display effect at high temperature, and others.

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The present invention discloses a liquid crystal composition and a display device containing the same. The liquid crystal composition comprises one or more compounds of general Formula I; one or more compounds of general Formula II; and one or more compounds of general Formula III. The liquid crystal composition provided in the present invention has the properties of large optical and dielectric anisotropies, high clearing point, fast response speed, high resistivity, and good high-temperature and UV stability, and is applicable to a liquid crystal display (LCD), and particularly an LCD display requiring fast response speed, such that a good display effect of images without ghosting can be achieved when the LCD display works in a harsh environment.

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To provide a liquid crystal composition satisfying at least one of characteristics such as high maximum temperature, low minimum temperature, small viscosity, suitable optical anisotropy, large negative dielectric anisotropy, large specific resistance, high stability to ultraviolet light and heat, or having a suitable balance regarding at least two of the characteristics; and an AM device having characteristics such as short response time, a large voltage holding ratio, low threshold voltage, a large contrast ratio and long service life. The composition has negative dielectric anisotropy and contains a specific compound having large negative dielectric anisotropy as a first component, 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 negative dielectric anisotropy as a fourth component, or a specific compound having a polymerizable group as an additive component.

The problem to be solved by the present invention is to provide: a liquid crystal composition suitable for a liquid crystal display element which hardly generates drop marks in production without worsening various characteristics thereof as liquid crystal display elements such as dielectric anisotropy, viscosity, nematic phase upper limit temperature, low-temperature nematic phase stability, y.sub.1 and others, and also burn-in characteristics of display elements, and which realizes a stable discharge amount of a liquid crystal material in an ODF process, and to provide a liquid crystal display element using the composition. The purpose of the present invention is to provide a liquid crystal composition provided with photosensitizing properties as the entire composition where a polymerizable monomer is combined with specific liquid crystal compounds.

The subject is to provide liquid crystal display device having a short response time, a large voltage holding ratio, a low threshold voltage, a large contrast ratio, a long service life and a small flicker rate.

The liquid crystal display device having a liquid crystal alignment film formed on the opposing surfaces of a pair of substrates, and a liquid crystal composition therebetween, wherein the liquid crystal alignment film includes a polymer derived from a polyamic acid having a photodegradable group, and the liquid crystal composition includes at least one compound represented by formula (1) as a first component:

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R.sup.1 is alkyl having 1 to 12 carbons or the like; ring A is 1,4-cyclohexylene, 1,4-phenylene or the like; Z.sup.1 is a single bond or the like; X.sup.1 and X.sup.2 are hydrogen or fluorine; Y.sup.1 is fluorine or the like; and a is 1, 2, 3 or 4.

An object of the present invention is to provide a composition that has positive Δ∈, 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 selected from compounds represented by general formula (iii). Moreover, a liquid crystal display device using the composition and an IPS or FFS device that uses the composition are provided.

Provided is a liquid crystal composition satisfying at least one of characteristics such as a high maximum temperature, a low minimum temperature, small viscosity, suitable optical anisotropy, large negative dielectric anisotropy, large specific resistance, high stability to ultraviolet light and high stability to heat, or has a suitable balance regarding at least two of the characteristics; and an AM device including the composition and having a short response time, a large voltage holding ratio, a low threshold voltage, a large contrast ratio or a long service life. The composition contains a specific compound having at least one polymerizable group, and a liquid crystal display device includes the composition. The composition may contain a specific compound having large negative dielectric anisotropy as a first component, and a specific compound having a high maximum temperature or small viscosity as a second component.

The present invention relates to liquid crystalline (LC) medium, to a method of its production and to the use of such LC media in polymer network liquid crystalline (PNLC) light modulation elements operated in the normally transparent mode. Furthermore, the present invention relates to such light modulation elements, as such, to the use of such light modulation elements as light shutters for transparent OLED displays, to the use of such light modulation elements in smart windows, and to a method of production of such light modulation elements according to the present invention.

Provided are a polymerizable compound having at least one monovalent group (A), a polymerizable composition containing the polymerizable compound, a liquid crystal composite prepared from the polymerizable composition, and a liquid crystal device having the polymerizable composition. ##STR00001## In monovalent group (A), R.sup.1 and R.sup.2 are independently hydrogen, halogen or alkyl having 1 to 20 carbons, and in the alkyl, at least one piece of —CH.sub.2— may be replaced by —O— or —S—, and at least one piece of —(CH.sub.2).sub.2— may be replaced by —CH═CH—, and in the groups, at least one hydrogen may be replaced by halogen.

A liquid-crystalline medium containing one or more compounds of formula IA, ##STR00001##
and the use thereof in an active-matrix display, in particular in a VA, IPS, U-IPS, FFS, UB-FFS, SA-VA, SA-FFS, PS-VA, PS-OCB, PS-IPS, PS-FFS, PS-UB-FFS, PS-posi-VA, PS-TN, polymer stabilised SA-VA or polymer stabilised SA-FFS display.