A liquid crystal composition has a negative dielectric anisotropy and contains a specific compound having large negative dielectric anisotropy as a first component, and a specific compound having small viscosity as a second component. The composition 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.

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

The subject is to shown a liquid crystal display device that has characteristics such as 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 disclosure relates to a liquid crystal display device having an electrode group formed on one or both of a pair of substrates that are opposed to each other, and a plurality of active devices connected to the electrode group, and a liquid crystal alignment film formed on the opposing surfaces of the pair of substrates, and a liquid crystal composition sandwiched in between the pair of substrates, wherein the liquid crystal alignment film includes a polymer having a photodegradable group, and the liquid crystal composition includes at least one compound selected from the group consisting of compounds represented by formula (1) as a first component: ##STR00001##

The present invention provides a liquid crystal alignment film not only having an excellent alignment property and stability, but also having high film strength, and thus exhibiting excellent durability and a high residual image property, a method for preparing the same, and a liquid crystal display device using the same.

The polymerizable liquid crystal compound has reverse wavelength dispersion or low wavelength dispersion and has high solubility in various solvents. The polymerizable liquid crystal compound provides an optically anisotropic body having high adhesiveness to substrates (or alignment films), by adding the polymerizable liquid crystal compound to a polymerizable composition and polymerizing the polymerizable composition using ultraviolet light. The invention provides a polymerizable composition containing the polymerizable liquid crystal compound having reverse wavelength dispersion or low wavelength dispersion, a polymer obtained by polymerizing the polymerizable composition, and an optically anisotropic body using the polymer. The present invention provides a polymerizable low wavelength dispersion or polymerizable reverse wavelength dispersion compound having in the molecule a partial structure represented by the general formula (AO-1); and also provides a composition containing the compound, a polymer obtained by polymerizing the composition, and an optically anisotropic body and the like using the polymer.

##STR00001##

An optical film includes a liquid crystal layer derived from a smectic phase, wherein an Nz factor of the liquid crystal layer is from 0.2 to 0.8. A display device that includes the optical film, and a method of producing an optical film is also provided.

Display device and:fabrication method thereof are provided. A display includes a polymer liquid crystal cell, including a first electrode layer, a second electrode layer, and a light-scattering adjustment layer between the first electrode layer and the second electrode layer; and a light source arranged on a first side of the polymer liquid crystal cell and configured to emit light into the light-scattering adjustment layer. The first electrode layer includes at least one first electrode. The second electrode layer includes at least one second electrode. The display region of the polymer liquid crystal cell includes a plurality of regions having a light-scattering ability increase along a direction away from the light source.

An object of the present invention is to provide a powder mixture containing a polymerizable liquid crystal compound, the powder mixture having a low risk of occurrence of fire due to the flammability of solvent, causing no changes in the appearance due to, for example, precipitation or crystallization of the solute during storage at low temperatures, causing no changes in the composition due to evaporation of solvent during long-term storage or leakage of solvent during long-term storage or transportation, being not viscous and having fluidity unlike nematic liquid crystal compositions, and being easily handled. Another object is to provide a nematic liquid crystal composition, a solution composition, cured products, optical films, and display devices that employ the above-described powder mixture.

Disclosed is a polymerizable compound having a structural formula as represented by the following formula I:

##STR00001##

The polymerizable compound disclosed in the present invention has a plurality of ring systems, and the entire molecular structure thereof is curved and twisted. The present invention further discloses a liquid crystal medium comprising the polymerizable compound, the polymerizable compound provided by the present invention has an appropriate polymerization rate in the liquid crystal medium, and the liquid crystal medium can be well applied to a PS-(polymer stabilized)- or PSA-(polymer stabilized alignment)-type liquid crystal display device. Further disclosed is a liquid crystal display device prepared from the liquid crystal medium.

There is provided a liquid crystal composition having the following properties without suffering reductions in refractive index anisotropy (n) and nematic phase-isotropic liquid phase transition temperature (T.sub.m): sufficiently low viscosity (), sufficiently low rotational viscosity (1), a large elastic constant (K.sub.33), and a negative dielectric anisotropy () with a large absolute value. There is also provided a liquid crystal display device of, for example, a VA type that uses such a liquid crystal composition and that has a high response speed and excellent display quality with defective display being eliminated or reduced. In particular, a liquid crystal composition having a negative dielectric anisotropy is provided, the composition containing a first component that is at least one compound represented by General Formula (i) and a second component that is at least one compound selected from compounds represented by General Formula (L).