Shown is a liquid crystal composition satisfying at least one or having suitable balance regarding at least two of characteristics such as high maximum or low minimum temperature of a nematic phase, large optical anisotropy, large positive dielectric anisotropy and high stability to ultraviolet light, a liquid crystal display device including such a composition, particularly including an encapsulated composition, and a liquid crystal display device including the composition serving as a constituent of 3D lens. The liquid crystal composition contains a specific compound having large optical anisotropy as a first component, and a specific compound having large optical anisotropy and positive dielectric anisotropy as a second component; a specific compound having large positive dielectric anisotropy as a third component; and a specific compound having large optical anisotropy and further having high maximum or low minimum temperature as a fourth component, and the liquid crystal display device includes the composition.

There is provided a liquid crystal composition which enables a significant reduction in crystallization temperature as compared with addition of a homolog while having a similar skeleton structure, which has an excellent compatibility, and which enables an increase in the absolute value of negative dielectric anisotropy (Δ∈). The liquid crystal composition contains two or more compounds which each have two to four ring structures between two side chains. At least one of the ring structures is a 2,3-difluorobenzene skeleton. The two side chains are bonded to different ring structures. The positions of the 2,3-difluorobenzene skeletons are different from each other, and the number of the ring structures are the same as each other.

The present invention relates to liquid-crystalline media (LC media) having negative or positive dielectric anisotropy comprising self-alignment additives (SAMs) with an at least one bifunctional or polyfunctional anchor group, which effects the homeotropic (vertical) alignment of the LC media at a surface or the cell walls of a liquid-crystal display (LC display). The invention therefore also encompasses LC displays having homeotropic alignment of the liquid-crystalline medium (LC medium) without conventional imide alignment layers. The LC media may be supplemented by a polymerizable or polymerized component, which serves for stabilization of the alignment, for adjustment of the tilt angle and/or as passivation layer.

The liquid crystal light modulator includes a first substrate (10) and a second substrate (20) disposed between two polarizers, and a pair of electrode structures (24, 24). The substrates include homeotropic alignment films (12) and (22), and at least one of the substrates has a function of aligning C-directors of liquid crystal molecules along one direction. The one direction forms an azimuth angle in the range of 35 to 55 degrees with the direction of the electric field generated by the pair of electrode structures (24, 24). A liquid crystal composition layer (31) contains a ferroelectric liquid crystal composition having a chiral smectic C phase or a liquid crystal composition that has an achiral smectic C phase and negative dielectric anisotropy. Light transmittance is modulated by the electric field generated by the electrode structures (24, 24) changing the birefringence index of the liquid crystal composition layer (31).

The present invention relates to a liquid crystal display device that includes a particular color filter containing a material containing chiral liquid crystals and a particular pigment. The present invention provides a liquid crystal display device that can prevent a decrease in the voltage holding ratio (VHR) of a liquid crystal layer and solve the problem of display defects, such as white spots, variations in alignment, and burn-in. Because liquid crystal display devices according to the present invention characteristically prevent a decrease in the voltage holding ratio (VHR) of a liquid crystal layer and reduces the occurrence of display defects, such as burn-in, the liquid crystal display devices are particularly useful as liquid crystal display devices in IPS mode and FFS mode for active-matrix driving and can be applied to household electrical appliances, automobiles, production facilities, measuring and analytical instruments, and communication devices.

The present invention relates to liquid-crystalline media (LC media) having negative or positive dielectric anisotropy, comprising a low-molecular-weight component and a polymerizable component. The polymerizable component comprises self-aligning, polymerizable mesogens (polymerizable self-alignment additives) which effect homeotropic (vertical) alignment of the LC media at a surface or the cell walls of a liquid-crystal display (LC display). The invention therefore also encompasses LC displays having homeotropic alignment of the LC medium without alignment layers. The invention discloses novel structures for self-alignment additives which have a certain position of the functional groups.

The compound is represented by general formula (i). In the compound, in a group K.sup.i1, at least two secondary carbon atoms in an alkyl group (a linear alkyl, halogenated alkyl, or cyanogenated alkyl group having 3 to 40 carbon atoms) are replaced with —C(═X.sup.i1)— and/or —CH(—CN)—, where X.sup.i1 is an oxygen atom, a sulfur atom, NH, or NR.sup.13; in addition, a group A.sup.i2, a group A.sup.i3, or the group K.sup.i1 includes, as a substituent, at least one P.sup.i1-Sp.sup.i1- group, where P.sup.i1 is a polymerizable group, and SP.sup.i1 is a spacer group or a single bond. The liquid crystal composition including the compound represented by general formula (i) can be adsorbed onto substrates between which a liquid crystal layer is held, and, consequently, without the use of an alignment film, liquid crystal molecules can be maintained in a state in which the liquid crystal molecules are aligned in a vertical direction. ##STR00001##

The disclosure provides a liquid crystal device including a liquid crystal composition containing a dichroic dye (dye-containing liquid crystal composition) that is in a light transmissive state when no voltage is applied to the transparent electrode and in a light scattering state when voltage is applied. The liquid crystal composition exhibits a negative dielectric constant anisotropy. The haze value of the liquid crystal device is 10% or less when no voltage is applied at 25° C., and the haze value is 50% or more when a rectangular wave voltage (AC 50 V, 60 Hz) is applied. The voltage holding ratio of the dye-containing liquid crystal composition is 60% or less at 25° C. The liquid crystal device provided by the disclosure is used as a component to provide a liquid crystal display apparatus, a light control apparatus, or a light transmitting apparatus with a high contrast.

The present invention provides a compound represented by formula (i), a liquid crystal composition using the compound, and a liquid crystal display device using the liquid crystal composition. The compound represented by formula (i) has a partial structure K.sup.i1 represented by any of general formulas (K-1) to (K-17) and further has ring B having at least two P-Sp- groups. Therefore, when used for a liquid crystal composition, the compound adsorbs to substrates sandwiching the liquid crystal composition (liquid crystal layer) and allows liquid crystal molecules to be held such that they are aligned in a vertical direction without a PI layer, and improved alignment stability and low-temperature storage stability can be achieved.

Provided are an alignment aid that sufficiently exerts an alignment control force causing liquid crystal molecules to be vertically aligned and can reduce a change in pretilt angle over time, a liquid crystal composition containing the alignment aid, and a liquid crystal display device. The alignment aid of the present invention has the function of causing the liquid crystal molecules to be aligned spontaneously. In the light absorption spectrum of the alignment aid, the longest wavelength at which the absorbance is 0.5 is 330 nm or shorter. Preferably, the light absorption spectrum is measured on a solution prepared by dissolving the alignment aid in tetrahydrofuran at a concentration of 1000 ppm.