The present invention relates to polymerisable compounds, to processes and intermediates for the preparation thereof, to liquid-crystal (LC) media comprising them, and to the use of the polymerisable compounds and LC media for optical, electro-optical and electronic purposes, in particular in LC displays, especially in LC displays of the polymer sustained alignment (PS, PSA) and self-aligning (SA) type.

Liquid-crystalline medium contains at least one compound of formula I,

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and at least one compound formulae ST-1 to ST-17 and the use thereof for an active-matrix display, in particular based on the VA, PSA, PA-VA, SS-VA, SA-VA, PS-VA, PALC, IPS, PS-IPS, UB-FFS, U-IPS, FFS or PS-FFS effect.

The present invention provides a liquid crystal display device that maintains a sufficient voltage holding ratio over a long period of time even when a liquid crystal panel having a narrower frame is used and that undergoes no burn-in or no stains on a display screen. The liquid crystal display device of the present invention includes an active-matrix liquid crystal panel and a backlight, wherein the liquid crystal panel includes a liquid crystal layer, a pair of substrates between which the liquid crystal layer is sandwiched, alignment layers disposed on surfaces of the pair of substrates facing the liquid crystal layer, and a seal part that bonds the pair of substrates to each other and that is disposed around the liquid crystal layer, and the liquid crystal panel is formed by a liquid crystal one-drop fill process, wherein the liquid crystal layer includes a liquid crystal material and at least one of a radical scavenger and an antioxidant, and the seal part has a width of 0.6 mm or less at least in part.

The present invention provides a liquid crystal display device that maintains a sufficient voltage holding ratio over a long period of time even when a liquid crystal panel having a narrower frame is used and that undergoes no burn-in or no stains on a display screen. The liquid crystal display device of the present invention includes an active-matrix liquid crystal panel and a backlight, wherein the liquid crystal panel includes a liquid crystal layer, a pair of substrates between which the liquid crystal layer is sandwiched, alignment layers disposed on surfaces of the pair of substrates facing the liquid crystal layer, and a seal part that bonds the pair of substrates to each other and that is disposed around the liquid crystal layer, and the liquid crystal panel is formed by a liquid crystal one-drop fill process, wherein the liquid crystal layer includes a liquid crystal material and at least one of a radical scavenger and an antioxidant, and the seal part has a width of 0.6 mm or less at least in part.

There is provided a liquid crystal composition including at least one compound represented by General Formula (i) and at least one compound represented by General Formula (N). The total amount of the compound represented by General Formula (i) is 10% by mass or greater. In the liquid crystal composition and the liquid crystal display element using the composition, the liquid crystal composition has a positive Δ∈ and a flat transmission characteristic curve. Therefore, gradation characteristics are easily controlled. Furthermore, display defects due to burn-in, dropping marks, and the like can be suppressed, and therefore excellent display quality is exhibited. The liquid crystal display element using this liquid crystal composition can be also provided.

There is provided a liquid crystal composition including at least one compound represented by General Formula (i) and at least one compound represented by General Formula (N). The total amount of the compound represented by General Formula (i) is 10% by mass or greater. In the liquid crystal composition and the liquid crystal display element using the composition, the liquid crystal composition has a positive Δ∈ and a flat transmission characteristic curve. Therefore, gradation characteristics are easily controlled. Furthermore, display defects due to burn-in, dropping marks, and the like can be suppressed, and therefore excellent display quality is exhibited. The liquid crystal display element using this liquid crystal composition can be also provided.

The present invention relates to liquid-crystalline media comprising one or more pleochroic dyes and one or more compounds selected from the group of compounds of formulae I, II and III,

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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.

The invention relates to a liquid crystal compound having the structure of formula I wherein R is selected from the group consisting of H and alkyl or alkoxy groups of 1 to 12 carbon atoms in which one or more H are unsubstituted or substituted with halogen; A.sub.1 is selected from the group consisting of a single bond or a 1,4-phenylene group in which each H in the 1,4-phenylene group is independently substituted by one or more halogen atoms; L.sub.1 and L.sub.2 are each independently selected from H or halogen; Z.sub.1 is a single bond or —(CH.sub.2).sub.2—. The compound has advantages of low rotational viscosity, large dielectric anisotropy, good mutual solubility and stability, which can be added to LC composition to reduce the driving voltage of the display. Thus, the novel compound has prosperous applications in LCD industry.

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The invention relates to a liquid crystal compound having the structure of formula I wherein R is selected from the group consisting of H and alkyl or alkoxy groups of 1 to 12 carbon atoms in which one or more H are unsubstituted or substituted with halogen; A.sub.1 is selected from the group consisting of a single bond or a 1,4-phenylene group in which each H in the 1,4-phenylene group is independently substituted by one or more halogen atoms; L.sub.1 and L.sub.2 are each independently selected from H or halogen; Z.sub.1 is a single bond or —(CH.sub.2).sub.2—. The compound has advantages of low rotational viscosity, large dielectric anisotropy, good mutual solubility and stability, which can be added to LC composition to reduce the driving voltage of the display. Thus, the novel compound has prosperous applications in LCD industry.

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Disclosed is a novel stabilizer represented by formula I,

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Further disclosed is a liquid crystal composition comprising a compound of formula I. The liquid crystal composition disclosed in the present invention has a low viscosity γ.sub.1, a moderate dielectric anisotropy Δ∈, a moderate optical anisotropy Δn, and most principally a high reliability, and can achieve a quick response of liquid crystal display.