A polar compound has a high chemical stability, high ability to align liquid crystal molecules and high solubility in a liquid crystal composition, and causes no decrease of liquid crystallinity of the liquid crystal composition, a liquid crystal composition contains the compound, and a liquid crystal display device includes the composition. The compound is represented by formula (1), the composition contains the compound, and the liquid crystal display device uses the composition. ##STR00001## In formula (1), R.sup.1 is alkyl having 3 to 15 carbons, alkenyl having 4 to 15 carbons or the like; a is an integer from 2 to 12; and R.sup.2 is a group represented by formula (1a), formula (1b) or formula (1c). ##STR00002## In the formulas, S.sup.1 and S.sup.2 are independently a single bond, alkylene having 1 to 10 carbons; S.sup.3 is >CH— or >N—; S.sup.4 is >C< or >Si<; and X.sup.1 is —OH, —NH.sub.2 or the like.

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.

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 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.

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.

The present invention relates to an LC medium comprising two or more polymerizable compounds, at least one of which contains a substituent comprising a tertiary OH group, to its use for optical, electro-optical and electronic purposes, in particular in LC displays, especially in LC displays of the PSA (polymer sustained alignment) or SA (self-aligning) mode, to an LC display of the PSA or SA mode comprising the LC medium, and to a process of manufacturing the LC display using the LC medium, especially an energy-saving LC display and energy-saving LC display production process.

The present invention belongs to the technical field of liquid crystal materials, and in particular relates to a liquid crystal composition and a liquid crystal display element or liquid crystal display containing the liquid crystal composition. The liquid crystal composition of the present invention is characterized in that the liquid crystal composition comprises more than or equal to 30% of a compound represented by Formula I, and also comprises one or more compounds represented by Formula II and one or more compounds represented by Formula III. The liquid crystal composition of the present invention has a high refractive index, a high clearing point and also a low rotational viscosity, and is mainly used for the display of a projector with a relatively high working temperature and a low cell thickness.

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An object of the invention is to provide conjugate fibers with an encapsulated liquid crystal, which can be used for forming a flexible liquid crystal display device, and the conjugate fibers without disturbance of arrangement of liquid crystal molecules within the fibers. The conjugate fibers according to the invention are sheath-core conjugate fibers having a liquid crystal composition as a core component, and the conjugate fibers with the encapsulated liquid crystal, in which the liquid crystal composition contains a halogen-containing liquid crystal compound.

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 the technical field of liquid crystal displays, and particularly relates to a liquid crystal composition containing a 2-methyl-3,4,5-trifluorobenzene liquid crystal compound and use thereof, wherein the liquid crystal composition of the present invention comprises, in percentages by weight, 1-50% of one or more compounds represented by general formula I and 10-70% of one or more compounds represented by general formula II, and may further comprise 0-30% of compounds represented by general formula III and/or 6-45% of one or more compounds represented by general formulas IV to XIII The liquid crystal composition provided by the present invention has a low rotational viscosity and a large elastic constant, is presented as having a shorter response time, and can significantly improve the display effect of a liquid crystal display when applied to TN, IPS and FFS mode displays.