Provided is an optically anisotropic layer with which an image display device having suppressed occurrence of oblique light leakage can be manufactured; and an optical film, a polarizing plate, and an image display device, each having the optically anisotropic layer. The optically anisotropic layer is obtained by curing a polymerizable liquid crystal composition including a predetermined rod-like liquid crystal compound and a predetermined monofunctional compound, and immobilizing an alignment state of the rod-like liquid crystal compound, in which a number a1 of atoms of the rod-like liquid crystal compound and a number a2 of atoms of the monofunctional compound satisfy a relationship of Expression (1): 0.2<a2/a1≤0.68, and the rod-like liquid crystal compound is immobilized in a state of being vertically aligned with respect to the main surface of the optically anisotropic layer.

Liquid crystal mixtures containing a photoalignment component A) containing a photoreactive mesogen of formula I,

##STR00001## a liquid-crystalline component B) containing one or more nematogenic compounds, and a polymerizable component C) containing one or more polymerizable compounds of formula P,

P.sup.a-Sp.sup.a-(A.sup.p).sub.n2-Sp.sup.b-P.sup.b  P and a method of producing such LC media, the use of such media in LC devices, and LC devices containing such a LC medium, and further a process for the fabrication of such liquid crystal displays and the use of the liquid crystal mixtures for the fabrication of such liquid crystal display.

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.

To provide a liquid crystal display device, whereby transparency when no voltage is applied and scattering properties when a voltage is applied, are good, adhesion between a liquid crystal layer and a vertical liquid crystal alignment film is high, and its lifespan is long even in a severe environment. The liquid crystal display device has a liquid crystal layer formed by disposing a liquid crystal composition containing a liquid crystal and a polymerizable compound between a pair of substrates provided with electrodes, and irradiating and curing the composition with ultraviolet rays by an ultraviolet irradiation apparatus, and at least one of the substrates is provided with a liquid crystal alignment film to vertically align a liquid crystal, wherein the ultraviolet irradiation apparatus is an ultraviolet irradiation apparatus capable of controlling the irradiation light intensity and wavelength of the ultraviolet rays to be irradiated and the surface temperature of the pair of the substrates, the liquid crystal composition contains a compound represented by the formula [1], and the liquid crystal alignment film is a liquid crystal alignment film obtained from a liquid crystal alignment treating agent containing a polymer having a side chain structure represented by the formula [2-1] or formula [2-2].

X.sup.1-X.sup.2-X.sup.3-X.sup.4-X.sup.5-X.sup.6X.sup.7.sub.pX.sup.8  [1]

(X.sup.1 is a specific side chain structure; X.sup.2, X.sup.3, X.sup.4 and X.sup.6 are each a single bond, etc.; X.sup.5 and X.sup.7 are each a benzene ring, etc.; p is an integer of from 0 to 4; and X.sup.8 is a C.sub.1-18 alkyl group, etc.),

—Y.sup.1-Y.sup.2-Y.sup.3-Y.sup.4Y.sup.5.sub.nY.sup.6  [2-1]

(Y.sup.1, Y.sup.2 and Y.sup.3 are each a single bond; Y.sup.4 and Y.sup.5 are each a benzene ring, etc.; n is from 0 to 4; and Y.sup.6 is a C.sub.1-18 alkyl group, etc.,

—Y.sup.7-Y.sup.8  [2-2]

(Y.sup.7 is a single bond; and Y.sup.8 is a C.sub.8-22 alkyl group, etc.).

It is an object of the present invention to provide a liquid crystal composition having positive Δ∈, having a liquid crystal phase in a wide temperature range, having high solubility at low temperatures, having high ODF process compatibility, having a high specific resistance and voltage holding ratio, and being insensitive to heat and light. In order to achieve this object, there is provided a liquid crystal composition containing at least one compound represented by the following general formula (i) and at least one compound represented by the following general formula (ii). ##STR00001## (wherein R.sup.i1 denotes an alkyl group having 2 to 5 carbon atoms) ##STR00002## (wherein R.sup.ii1 and R.sup.ii2 independently denote an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and X.sup.ii1 and X.sup.ii2 independently denote a hydrogen atom or a fluorine atom)

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 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.

A liquid-crystal (LC) medium which is based on a mixture of polar compounds and is substantially dielectrically neutral, its use for optical, electro-optical and electronic purposes, in particular as optical retarder or optical compensator in LC displays, an optical retarder or optical compensator containing the LC medium, an optical, electrooptical or electronic device containing the optical retarder or optical compensator, and a process of manufacturing the optical retarder or optical compensator.

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.

The present invention relates to a process of preparing a light modulation element of the PS-ULH (polymer stabilised ULH) type, which allows to reduce the operational voltage and allows to improve the switching time of the light modulation element.