The invention relates to a liquid-crystalline medium, preferably having a nematic phase and dielectric anisotropy of 0.5 or more, which comprises one or more compounds of formula D

##STR00001## in which the parameters have the meanings given in the text,
to the use thereof in an electro-optical display, particularly in an active-matrix display based on the IPS or FFS effect, to displays of this type which contain a liquid-crystalline medium of this type, and to the compounds of formula T and their use for the improvement of the transmission and/or response times of a liquid-crystalline medium which comprises one or more additional mesogenic compounds.

A polymerizable LC material comprising one or more reactive mesogenic compounds, one or more chiral compounds and a block copolymer that comprises at least one polyfluorooxetane block bonded to a polyether block, said polyfluorooxetane block having a repeating unit of the formula ##STR00001## Further, a method for its preparation, a polymer film obtainable from a corresponding polymerizable LC material, a method of preparation of such polymer film, and the use of such polymer film and said polymerizable LC material in optical, electro-optical, decorative or security devices.

An optical film, a polarizing plate, and an image display device, each having an optically anisotropic layer obtained by curing a polymerizable liquid crystal composition including a polymerizable liquid crystal compound (LCC) having forward wavelength dispersion and a monofunctional compound, and immobilizing an alignment state of the polymerizable LCC. The number a.sub.1 of atoms of the polymerizable LCC and the number a.sub.2 of atoms of the monofunctional compound satisfy a relationship of Expression (1): 0.2<a.sub.2/a.sub.1<0.55; the number b.sub.1 of the rings B.sup.1 contained in the polymerizable LCC and the total number b.sub.2 of the aromatic rings Ar and the rings B.sup.2 contained in the monofunctional compound satisfy a relationship of Expression (2): b.sub.2=b.sub.1×0.5 or b.sub.2=(b.sub.1+1)×0.5.

The present invention discloses a compound of which a structural formula thereof is represented as the following formula: ##STR00001##
The compound disclosed by the present invention can be used as a liquid crystal compound and overcomes the problem that solubility of the traditional dibenzothiophene-class liquid crystals is poor, and thus can be better applied to the liquid crystal material field. The present invention further discloses a liquid crystal medium containing the compound and an application thereof.

A liquid-crystalline medium, preferably having a nematic phase and dielectric anisotropy of 0.5 or more, which comprises one or more compounds of each of formulae T and L ##STR00001##
in which the parameters have the meanings given in the claims and in the text. The use thereof in an electro-optical display, particularly in an active-matrix display based on the IPS or FFS effect, to displays of this type which contain a liquid-crystalline medium of this type. Also, the compounds of formulae T and L and their use for the improvement of the transmission and/or response times of a liquid-crystalline medium which comprises one or more additional mesogenic compounds.

A polymerizable LC material comprising one or more reactive mesogenic compounds, one or more chiral compounds and a block copolymer that comprises at least one polyfluorooxetane block bonded to a polyether block, said polyfluorooxetane block having a repeating unit of the formula

##STR00001##

Further, a method for its preparation, a polymer film obtainable from a corresponding polymerizable LC material, a method of preparation of such polymer film, and the use of such polymer film and said polymerizable LC material in optical, electro-optical, decorative or security devices.

A polymerisable LC material comprising one or more di- or multireactive mesogenic compounds and one or more compounds of formula UVI,

##STR00001##

and one or more compounds of formula UVII,

##STR00002##

Further, a method for its preparation, a polymer film with improved thermal durability and UV stability obtainable from a corresponding polymerisable LC material, a method of preparation of such polymer film, and the use of such polymer film and said polymerisable LC material for optical, electro-optical, decorative or security devices.

The invention relates to a polymerisable LC material comprising one or more di- or multireactive mesogenic compounds and one or more compounds of formula UVI,

##STR00001##

wherein the individual radicals have one of the meaning as given in the claims. Furthermore, the present invention relates also to a method for its preparation, a polymer film with improved thermal durability and UV stability obtainable from a corresponding polymerisable LC material, to a method of preparation of such polymer film, and to the use of such polymer film and said polymerisable LC material for optical, electrooptical, decorative or security devices.

An object of the present invention is to provide a compound having an excellent rate of change in HTP caused by exposure. Another object of the present invention is to provide a liquid crystal composition formed of the compound, a cured product, an optically anisotropic body, and a reflective film.

The compound of the present invention is represented by General Formula (1).

##STR00001##

In General Formula (1), a portion where a solid line and a broken line are parallel to each other represents a single bond or a double bond.

In General Formula (1), X.sup.1 to X.sup.8 each independently represent a hydrogen atom or a monovalent substituent. However, at least one of X.sup.1, X.sup.3, X.sup.5, or X.sup.7 and at least one of X.sup.2, X.sup.4, X.sup.6, or X.sup.8 represent a substituent including a group represented by General Formula (2).

##STR00002##

In General Formula (2), Z represents a single bond or —O—. Y.sup.1 and Y.sup.2 each independently represent a hydrogen atom or a hydrocarbon group not including an aryl group. *1 and *2 represent bonding positions.

The present invention relates to a liquid-crystal material (LC media) comprising thiophene derivatives which are stabilised by sterically hindered amines or amine derivatives (HALS, hindered amine light stabilisers), and to liquid-crystal displays (LC displays) which contain these LC materials.