The present invention relates to liquid crystal (LC) media comprising one or more polymerisable compounds as further specified in the description or claims and a self-alignment additive for vertical alignment. The media are adapted for use in LC displays, especially in LC displays of the polymer-sustained alignment type.

The invention relates to a compound of formula I,

##STR00001##

wherein R.sup.11, R.sup.21, A.sup.11, A, Z, X.sup.11, X.sup.21, Y.sup.11, Y.sup.12, Sp.sup.11, Sp.sup.21, o and p have one of the meanings as given in claim 1. The invention further relates to method of production of a compound of formula I, to the use of said compounds in LC media and to LC media comprising one or more compounds of formula I. Further, the invention relates to a method of production of such LC media, to the use of such media in LC devices, and to LC device comprising a LC medium according to the present invention. The present invention further relates to a process for the fabrication such liquid crystal display and to the use of the liquid crystal mixtures according to the invention for the fabrication of such liquid crystal display.

A liquid-crystalline medium which comprises at least one compound selected from the group of compounds of the formulae IA to IH,

##STR00001##

in which Z.sup.1 denotes a single bond, —CH.sub.2CH.sub.2—, —CH═CH—, —CH.sub.2O—, —OCH.sub.2—, —CF.sub.2O—, —OCF.sub.2—, —COO—, —OCO—, —C.sub.2F.sub.4—, —(CH.sub.2).sub.4—, —CHFCHF—, —CF.sub.2CH.sub.2—, —CH.sub.2CF.sub.2—, —C≡C—, —CF═CF—, —CH═CHCHO— or —CH.sub.2CF.sub.2O—,
and the use thereof for an active-matrix display, in particular based on the VA, PSA, PS-VA, PALC, FFS, PS-FFS, SA-VA, PS-IPS or IPS effect.

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

Provided is a polar compound having high chemical stability, high capability of aligning liquid crystal molecules, high solubility in a liquid crystal composition, and a large voltage holding ratio when used in a liquid crystal display device. The compound is represented by formula (1):

##STR00001##

in which, for example, R.sup.1 is alkyl having 1 to 15 carbons; MES is a mesogen group having at least one ring; Sp.sup.1 is a single bond or alkylene having 1 to 10 carbons; M.sup.1 and M.sup.2 are hydrogen; and R.sup.2 is a group represented by formulas (1a) to (1c):

##STR00002##

in which, Sp.sup.2 and Sp.sup.a are a single bond or alkylene having 1 to 10 carbons; S.sup.1 is >CH—; S.sup.2 is >C<; and X.sup.1 is —OH.

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.

A problem of the present invention is to provide a polymerizable compound and a polymerizable composition which cause little decrease in retardation and discoloration when a film-shaped polymer produced by polymerization is irradiated with ultraviolet/visible light for a long time at high temperature. A further problem is to provide a polymer produced by polymerizing the polymerizable composition and an optically anisotropic body using the polymer. As a result, a compound useful as a component of a polymerizable composition was obtained. An optically anisotropic body using a polymerizable liquid crystal composition containing the compound of the present invention is useful for application to an optical film and the like.

The present invention relates to liquid-crystalline media comprising one or more pleochroic dyes and one or more compounds selected from the group of compounds of formulae I, II and III,

##STR00001##

in which the parameters have the meaning indicated in Claim 1, and to components comprising these media for high-frequency technology, in particular phase shifters and microwave array antennas.

The invention relates to a liquid crystal compound having the structure of formula I wherein R is selected from the group consisting of H and alkyl or alkoxy groups of 1 to 12 carbon atoms in which one or more H are unsubstituted or substituted with halogen; A.sub.1 is selected from the group consisting of a single bond or a 1,4-phenylene group in which each H in the 1,4-phenylene group is independently substituted by one or more halogen atoms; L.sub.1 and L.sub.2 are each independently selected from H or halogen; Z.sub.1 is a single bond or —(CH.sub.2).sub.2—. The compound has advantages of low rotational viscosity, large dielectric anisotropy, good mutual solubility and stability, which can be added to LC composition to reduce the driving voltage of the display. Thus, the novel compound has prosperous applications in LCD industry.

##STR00001##

The invention relates to a liquid crystal compound having the structure of formula I wherein R is selected from the group consisting of H and alkyl or alkoxy groups of 1 to 12 carbon atoms in which one or more H are unsubstituted or substituted with halogen; A.sub.1 is selected from the group consisting of a single bond or a 1,4-phenylene group in which each H in the 1,4-phenylene group is independently substituted by one or more halogen atoms; L.sub.1 and L.sub.2 are each independently selected from H or halogen; Z.sub.1 is a single bond or —(CH.sub.2).sub.2—. The compound has advantages of low rotational viscosity, large dielectric anisotropy, good mutual solubility and stability, which can be added to LC composition to reduce the driving voltage of the display. Thus, the novel compound has prosperous applications in LCD industry.

##STR00001##