The present, invention provides a liquid crystal display device that can exhibit excellent retardation stability against heat and that can prevent reduction in contrast ratio due to scattering even when the liquid crystal display device includes a retardation layer formed by polymerization of a reactive monomer, and a method for producing a liquid crystal display device suitable for production of the liquid crystal display device. The liquid crystal display device of the present invention includes paired substrates and a liquid crystal layer provided between the paired substrates. At least one of the paired substrates includes a retardation layer formed from a polymer of at least one type of monomer. The at least one type of monomer includes a photo-aligning monomer that is to be aligned by polarized light.

The invention relates to bimesogenic compounds of formula I

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wherein R.sup.11, R.sup.12, MG.sup.11, MG.sup.12, X.sup.11, X.sup.12 and Sp.sup.1 have the meaning given in claim 1, to the use of bimesogenic compounds of formula I in liquid crystal media and particular to flexoelectric liquid crystal devices comprising a liquid crystal medium according to the present invention.

There is provided a liquid crystal composition that exhibits a sufficiently low viscosity (η), a sufficiently low rotational viscosity (γ1), and a large elastic modulus (K.sub.33) without decreasing the refractive index anisotropy (Δn) and the nematic phase-isotropic liquid phase transition temperature (T.sub.ni) and without increasing the solid phase-nematic phase transition temperature (T.sub.cn). The liquid crystal display element that uses this liquid crystal composition satisfactorily obtains a pretilt angle and has a high voltage holding ratio (VHR) and high-speed response. Thus, a liquid crystal display element that has no or less alignment defects and display defects such as image sticking, and has high display quality and high response speed is obtained.

The present invention relates to a PSA-mode liquid crystal display device including a polymer produced by polymerizing a polymerizable compound by energy ray irradiation in a state in which a mixture of the polymerizable compound and a liquid crystal composition is held between the first substrate and the second substrate, the polymer having a number-average molecular weight of 50,000 or more in terms of polystyrene. In a PSA-mode display device in which alignment of liquid crystal molecules substantially vertically aligned between the substrates is controlled by applying a voltage, a pre-tilt angle can be properly given without being inhibited. Therefore, the present invention provides a PSA-mode display device with good alignment stability, uniform alignment within the substrates, and no or suppressed display defects and a method for producing the same.

The present invention relates to compounds that have ultraviolet light absorbing properties, and which can also have mesogenic properties. The present invention also relates to compositions that include one or more such compounds, and to articles of manufacture that include one or more such compounds, such as optical elements that include an optical substrate and a layer that includes at least one compound of the present invention.

A compound having a maximum absorption in a wavelength range of 350 nm to 550 nm that functions as a dichroic dye is provided. In particular, a compound represented by formula (1) is provided. In the compound represented by formula (1), R.sup.1 represents a hydrogen atom or the like; R.sup.2 represents an acyl group having 1 to 20 carbon atoms or the like; R.sup.3 represents a hydrogen atom or the like; and Y represents a group of formula (Y1). In the group of formula (Y1), * represents a bonding site with N, or a group of formula (Y2); and in the group of formula (Y2), * represents a bonding site with N; P.sup.1 and P.sup.2 each independently represent —S— or the like; and Q.sup.1 and Q.sup.2 each independently represent ═N— or the like.

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A compound having a maximum absorption in a wavelength range of 350 nm to 550 nm that functions as a dichroic dye is provided. In particular, a compound represented by formula (1) is provided. In the compound of formula (1), R.sup.1 represents a hydrogen atom or the like; R.sup.2 represents a hydrogen atom or the like; R.sup.3 represents a hydrogen atom or the like; Z represents —CO— or the like; and Y represents a group of formula (Y1). In the group of formula (Y1), * represents a bonding site with N, or a group of formula (Y2); and in the group of formula (Y2), * represents a bonding site with N; P.sup.1 and P.sup.2 each independently represent —S— or the like; and Q.sup.1 and Q.sup.2 each independently represent ═N— or the like.

##STR00001##

There is provided a polymerizable compound-containing liquid crystal composition having strong alignment regulating force of a liquid crystal compound. The polymerizable compound-containing liquid crystal composition includes: a polymerizable compound; and a liquid crystal compound, in which the polymerizable compound includes at least one polymerizable compound represented by General Formula (I), and in which the liquid crystal compound includes at least one component selected from the group consisting of at least one compound represented by General Formula (II) as a second component, at least one compound represented by General Formulae (IIIa), (IIIb), and (IIIc) as a third component, and at least one compound represented by General Formulae (IVa), (IVb), and (IVc) as a fourth component.

An optical film of the present invention includes a positive A-plate and a positive C-plate, in which the Re(450), Re(550), and Re(650) of the positive A-plate satisfy the relationship of Re(450)≦Re(550)≦Re(650), the positive A-plate is formed of a cured product of a composition including the liquid crystal compound A, and the positive C-plate is formed of a cured product of a composition including the liquid crystal compound C.

There is provided a liquid crystal display device which enables reductions in image sticking and droplet stains caused in production thereof without degradation of properties such as dielectric anisotropy, viscosity, the upper limit of the temperature of nematic phase, and rotational viscosity (γ.sub.1); and there is also provided a method for manufacturing such a liquid crystal display device. The liquid crystal display device is characterized in that a liquid crystal layer containing a liquid crystal composition is disposed between a substrate provided with a common electrode and a color filter layer and another substrate provided with a plurality of pixels each having a pixel electrode, each of the substrates is not provided with an alignment film but provided with an orientation controlling layer composed of at least two polymerizable compounds, each of the pixels has two or more regions having different directions of pretilt, and the liquid crystal composition contains a compound represented by General Formula (I) and a compound represented by General Formula (II).