A liquid crystal composition containing a polymerizable compound of the present invention has excellent characteristics of being able to prepare a PSA type liquid crystal display element with no problem of depositing in a wide temperature range, having high polymerization speed, high liquid crystal alignment regulation force after polymerization, excellent display qualities with no display unevenness, and excellent display characteristics with no defects in display characteristics such as image sticking and is appropriate as a liquid crystal composition in a practical use. Further, the liquid crystal display element with the above-described liquid crystal composition can be appropriately used for a PSA type liquid crystal display element.

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.

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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 CHCH, and in the groups, at least one hydrogen may be replaced by halogen.

A liquid crystal composition satisfying at least one characteristic such as high maximum temperature, low minimum temperature, small viscosity, suitable optical anisotropy, large negative dielectric anisotropy, large specific resistance, high stability to UV light or to heat, or having a suitable balance regarding at least two of the characteristics, and an AM device having characteristics such as a short response time, a large voltage holding ratio, a low threshold voltage, a large contrast ratio and a long service life are shown. The liquid crystal composition contains a specific compound having at least three polymerizable groups, and the 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.

Shown is a liquid crystal composition satisfying at least one of characteristics such as a high maximum temperature, a low minimum temperature, a small viscosity, a suitable optical anisotropy and a large dielectric anisotropy, 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 negative dielectric anisotropy as a first component, and a specific compound having small viscosity as a second component, and may contain a specific compound having negative dielectric anisotropy as a third component, a specific compound having a high maximum temperature or small viscosity as a fourth component or a specific compound having a polymerizable group as an additive component.

[Object] An object of the present invention is to provide a liquid crystal composition containing a polymerizable compound for use in the manufacture of a PSA or PSVA liquid crystal display device. The polymerizable compound has a sufficiently high polymerization rate. The PSA or PSVA liquid crystal display device has few or no display defects due to a change in pretilt angle, has an adequate pretilt angle, and has high responsiveness. The present invention also provides a liquid crystal display device having the liquid crystal composition.

[Solution] The object is achieved by using a liquid crystal composition containing one or two or more polymerizable compounds represented by the general formula (I).

A liquid crystal composition, a liquid crystal display (LCD) device using the liquid crystal composition, and a method of manufacturing an LCD device are provided. The liquid crystal display device comprises: a first substrate; a liquid crystal layer disposed on the first substrate, the liquid crystal layer including a liquid crystal compound; and a first liquid crystal alignment layer disposed between the first substrate and the liquid crystal layer, wherein the first compound includes a first compound, which has at least one hydrophilic group bonded to one end of a core structure thereof and a benzoyl derivative moiety bonded to the other end of the core structure thereof.

A liquid crystal display device, whereby transparency when no voltage is applied and scattering properties when a voltage is applied, are good, adhesion between a liquid crystal layer and a vertical liquid crystal alignment film is high, and its lifespan is long even in a severe environment. The liquid crystal display device has a liquid crystal layer formed by disposing a liquid crystal composition containing a liquid crystal and a polymerizable compound between a pair of substrates provided with electrodes, and irradiating and curing the composition with ultraviolet rays by an ultraviolet irradiation apparatus, and at least one substrate is provided with a liquid crystal alignment film to vertically align a liquid crystal, wherein the ultraviolet irradiation apparatus is an ultraviolet irradiation apparatus capable of controlling the irradiation light intensity and wavelength of the ultraviolet rays to be irradiated and the surface temperature of the pair of the substrates.

A negative liquid crystal material includes a liquid crystal compound and a viscosity-decreasing agent. The liquid crystal compound has a negative dielectric anisotropy. The viscosity-decreasing agent is represented by the following chemical formula (1):

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in the chemical formula (1), X and Y are each H or a halogen group, and at least one of X and Y is a halogen group; and R and R are each a linear saturated alkyl group having 1 to 5 carbon atoms or a linear saturated alkoxy group having 1 to 5 carbon atoms.

Liquid-crystalline (LC) media having positive dielectric anisotropy and liquid-crystal displays (LCDs) containing these media, especially displays addressed by an active matrix and in particular to LC displays of the TN, PS-TN, STN, TN-TFT, OCB, IPS, PS-IPS, FFS, HB-FFS, XB-FFS, PS-FFS, SA-HB-FFS, SA-XB-FFS, polymer stabilised SA-HB-FFS, polymer stabilised SA-XB-FFS, positive VA or positive PS-VA type.

A liquid crystal composition includes at least one compound represented by formula I and at least one compound represented by formula II. The liquid crystal composition has a relatively large absolute value of dielectric anisotropy, a relatively large K value, a relatively long low-temperature storage time period, a relatively low polymer layer surface roughness, a relatively small pre-tilt angle, a relatively fast speed for forming pre-tilt angle, a relatively low polymer residue, a relatively high VHR and a relatively good pre-tilt angle stability, while maintaining appropriate clearing points, optical anisotropy and rotational viscosity. A liquid crystal display device containing the liquid crystal composition has a relatively wide temperature usage range, relatively good contrast, and relatively good low-temperature mutual solubility. In addition, the production process of PSA-type liquid crystal displays is improved, and at the same time, the problems of image sticking, uneven display and broken bright spots.

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