An optically anisotropic layer including a polymer and a compound having a mesogen skeleton, wherein the polymer has a property such that a film of the polymer that is formed by a coating method using a solution of the polymer satisfies nz(P)>nx(P)?ny(P), wherein nx(P) is a refractive index in a direction which, among in-plane directions of the film, gives a maximum refractive index, ny(P) is a refractive index in a direction which is perpendicular to the direction of nx(P) among the in-plane directions of the film, and nz(P) a refractive index in a thickness direction of the film, and the compound having a mesogen skeleton shows an in-plane retardation with reverse wavelength distribution under specific conditions.

A liquid crystal composition including a polymerizable liquid crystal compound capable of expressing birefringence with reverse wavelength distribution and a surfactant containing a fluorine atom, a 1-octanol/water partition coefficient of the surfactant being less than 5.0.

The present invention relates to a liquid crystalline medium comprising dichroitic dyes made of benzothiadiazoles and related extended heterocyclic derivatives, the use of said medium for optical, electro-optical and electronic purposes, in particular in devices for regulating the passage of radiation energy from an outside space into an inside space, for example in windows. The invention further relates to devices containing the liquid crystalline medium according to the invention. Some new dichroitic dyes are disclosed.

A polymerizable compound, a polymerizable composition, and a polymer, which have a low melting point at a practical level and exhibit excellent solubility in a general-purpose solvent, can be produced at low cost. The polymerizable compound, polymerizable composition, and polymer can produce an optical film, which exhibits excellent transparency and achieves uniform conversion of polarized light over a wide wavelength band, and an optically anisotropic article. The polymerizable compound is represented by formula (I). ##STR00001##

A liquid crystal cured film includes a liquid crystal cured layer formed of a cured product of a liquid crystal composition containing a polymerizable liquid crystal compound capable of expressing birefringence with reverse wavelength distribution, the polymerizable liquid crystal compound containing an ethylenically unsaturated bond and an aromatic ring. The film satisfies 1.00<X(S)/X(A), where X(S) represents a peak ratio X of one surface of the liquid crystal cured layer; X(A) is a peak ratio X of the other surface of the liquid crystal cured layer; the peak ratio X is a ratio represented by X=I(1)/I(2); I(1) is a peak strength derived from in-plane deformation vibration of the ethylenically unsaturated bond in measurement of infrared total reflection-absorption spectrum; and I(2) is a peak strength derived from stretching vibration of an unsaturated bond of the aromatic ring in measurement of infrared total reflection-absorption spectrum.

The present invention provides a novel method for producing an ester group-containing compound and a derivative produced using the compound as a synthetic intermediate. The invention also provides a polymerizable composition containing the compound obtained by the production method and a film-shaped polymer obtained by polymerizing the polymerizable composition. The present invention is a method for producing an ester group-containing compound, the method including a mixing step of mixing a condensing agent, a Bronsted acid, a carboxylic acid, and a phenol or an alcohol to prepare a reaction mixture. The Bronsted acid selected is other than the condensing agent, the carboxylic acid, and the phenol.

A polymerizable composition of the present invention has favorable solubility, and an optically anisotropic body using the polymerizable composition is unlikely to discolor and is excellent in heat resistance and light resistance. The problem to be solved by the present invention is to provide a polymer obtained by polymerizing the polymerizable composition and an optically anisotropic body using the polymer. The present invention relates to a polymerizable composition which includes a compound having at least one mesogenic group and satisfying an expression represented by Expression (1), and which satisfies an expression represented by Expression (2).

0.5YI/n500Expression (2)

An object of the present invention is to provide an optical film having an optically anisotropic layer having excellent durability, and a polarizing plate and an image display device using the same. This optical film of the present invention is an optical film at least having an optically anisotropic layer, in which the optically anisotropic layer is a layer obtained by polymerizing a polymerizable liquid crystal composition containing a predetermined liquid crystal compound, a predetermined mesogen compound, and a polymerization initiator, an I/O value of the liquid crystal compound is more than 0.56, and an I/O value of the mesogen compound is 0.56 or less.

An object of the invention is to provide a coloring composition which can form a light absorption anisotropic film having an excellent dichroic ratio, a dichroic dye compound, a light absorption anisotropic film, a laminate, and an image display device. A coloring composition according to the invention contains a dichroic dye compound which has a Hansen solubility parameter of 17.5 or greater and has a structure represented by Formula (1), and a liquid crystalline compound.

L.sup.1-A.sup.1-N?N-A.sup.2-N?N-A.sup.3-L.sup.2(1) in Formula (1), A.sup.1, A.sup.2, and A.sup.3 each independently represent a divalent aromatic group which may have a substituent. Any one of A.sup.1, A.sup.2, and A.sup.3 represents a divalent thienothiazole group which may have a substituent. In Formula (1), L.sup.1 and L.sup.2 each independently represent a substituent.

The polymerizable liquid crystal compound has reverse wavelength dispersion or low wavelength dispersion and has high solubility in various solvents. The polymerizable liquid crystal compound provides an optically anisotropic body having high adhesiveness to substrates (or alignment films), by adding the polymerizable liquid crystal compound to a polymerizable composition and polymerizing the polymerizable composition using ultraviolet light. The invention provides a polymerizable composition containing the polymerizable liquid crystal compound having reverse wavelength dispersion or low wavelength dispersion, a polymer obtained by polymerizing the polymerizable composition, and an optically anisotropic body using the polymer. The present invention provides a polymerizable low wavelength dispersion or polymerizable reverse wavelength dispersion compound having in the molecule a partial structure represented by the general formula (AO-1); and also provides a composition containing the compound, a polymer obtained by polymerizing the composition, and an optically anisotropic body and the like using the polymer.

##STR00001##