Disclosed herein is a light emitting device and method of manufacturing such a device comprised of a series of photopolymerizable, chiral liquid crystalline layers that can be solvent cast on a substrate. The mixture of chiral materials in each successive layer may be blended in such a way that each layer has the same chiral pitch. Further the chiral materials in each layer may also be blended so that the ordinary and extraordinary refractive indices in each layer match the other layers such that the complete assembly of layers will optically function as a single relatively thick layer of chiral liquid crystal. The chiral nematic material in each layer can spontaneously adopt a helical structure with a helical pitch. The light emitting layers of the light emitting device can further comprise electroluminescent material that emits light into the band edge light propagation modes of the photonic crystal.

A phase difference film is formed by using a liquid crystal compound and that indicates an Nz factor of more than 0 and less than 1, an optical film with same, and a display device. The phase difference film is formed by using a composition including a polymerizable liquid crystal compound having a mesogen group, where an order parameter of the mesogen group in an in-plane slow axis direction of the phase difference film is set as Sx, an order parameter of the mesogen group in a direction orthogonal to the in-plane slow axis direction in a plane is set as Sy, and an order parameter of the mesogen group in a thickness direction of the phase difference film is set as Sz, in a case where the mesogen group has a rod or a disc shape, differing Expressions are satisfied.

The invention relates to a polymerisable LC material comprising at least one di- or multireactive mesogenic compound of formula T,

R.sup.T1-(A.sup.T1Z.sup.T1).sub.m1-G.sup.T1-(Z.sup.T2-A.sup.T2).sub.m2-R.sup.T2T

and at least one compound of formula CO-1,

##STR00001##

wherein the parameter are R.sup.T1, A.sup.T1, Z.sup.T1, m1, G.sup.T1, Z.sup.T2, A.sup.T2, m2, R.sup.T2, L.sup.1 to L.sup.3, R.sup.1 and R.sup.2, and n are defined as given in claim 1.

Furthermore, the present invention relates also to a method for its preparation, a polymer film with improved thermal durability obtainable from the 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, electro-optical, decorative or security devices.

The present invention provides an optically anisotropic film exhibiting excellent reciprocal wavelength dispersion, a circularly polarizing plate, and a display device. The optically anisotropic film of an embodiment of the present invention is an optically anisotropic film formed from a composition including a liquid crystal compound and an infrared absorbing dye, in which the optically anisotropic film satisfies a relationship of Formula (A): Re(450)/Re(550)<1, and an absorption at a wavelength of 700 to 900 nm in the fast axis direction of the optically anisotropic film is larger than an absorption at a wavelength of 700 to 900 nm in the slow axis direction of the optically anisotropic film. In Formula (A), Re(450) represents an in-plane retardation of the optically anisotropic film at a wavelength of 450 nm and Re(550) represents an in-plane retardation of the optically anisotropic film at a wavelength of 550 nm.

A polymerizable liquid crystal composition containing two polymerizable liquid crystal compounds (A) and (B) is provided. A polymer of compound (A) exhibits a reverse wavelength dispersion property and the phase difference value [R(A,3000,450)] at a wavelength of 450 nm measured after irradiation in an oriented state with ultraviolet ray at 3000 mJ/cm.sup.2 varies in a positive sense relative to the phase difference value [R(A,500,450)] at a wavelength of 450 nm measured after irradiation in an oriented state with ultraviolet ray at 500 mJ/cm.sup.2. A polymer of compound (B) exhibits a reverse wavelength dispersion property and the phase difference value [R(B,3000,450)] at a wavelength of 450 nm measured after irradiation in an oriented state with ultraviolet ray at 3000 mJ/cm.sup.2 varies in a negative sense relative to the phase difference value [R(B,500,450)] at a wavelength of 450 nm measured after irradiation in an oriented state with ultraviolet ray at 500 mJ/cm.sup.2.

The present invention is related to the filed of optically variable security elements comprising a region based on a single cured ink comprising a cholesteric liquid crystal polymer, said region having at least two, preferably at least three, patterns exhibiting, at at least one viewing angle, a different CIE (1976) color index parameter and/or a different position of the selective reflection band for protecting security documents against counterfeiting and/or illegal reproduction. In particular, the present invention relates to processes for manufacturing said features, when the processes comprises the steps of a) applying on a substrate by a rotogravure process with the use of a gravure cylinder having at least two, preferably at least three, different engravings a single cholesteric liquid crystal precursor composition, b) heating the applied composition to bring said composition to a cholesteric liquid crystal state, and c) curing the composition so as to form the region based on a single cured ink comprising a cholesteric liquid crystal polymer.

A liquid crystal composition including: a polymerizable liquid crystal compound capable of expressing birefringence with inverse wavelength dispersion; and a (meth)acrylate compound containing two or more (meth)acryloyl groups per one molecule, wherein: an amount of the (meth)acrylate compound is 8 parts by weight or less, the amount being relative to 100 parts by weight of a sum total of the polymerizable liquid crystal compound and the (meth)acrylate compound.

The present invention has an object to provide a polymerizable liquid crystal compound used for formation of an optically anisotropic film having excellent reciprocal wavelength dispersion, a polymerizable liquid crystal composition, an optically anisotropic film, an optical film, a polarizing plate, and an image display device. The polymerizable liquid crystal compound of an embodiment of the present invention is a polymerizable liquid crystal compound represented by Formula (1), in which a Clog P value of a group represented by Ar in Formula (1) is 3.5 or less.

##STR00001##

The present invention has an object to provide a polymerizable liquid crystal compound used for formation of an optically anisotropic film having excellent reciprocal wavelength dispersion and moisture-heat resistance, a polymerizable liquid crystal composition, an optically anisotropic film, an optical film, a polarizing plate, and an image display device. The polymerizable liquid crystal compound of the present invention is a polymerizable liquid crystal compound represented by Formula (1), in which a Clog P value of a group represented by Ar in Formula (1) is 4.3 or more and less than 7.0.

##STR00001##

A liquid crystal composition including a liquid crystal compound capable of expressing a birefringence with reverse wavelength distribution, a (meth)acrylic acid ester compound other than the liquid crystal compound, and a surfactant containing a fluorine atom, wherein a ratio Mw/Np of a molecular weight Mw of the (meth)acrylic acid ester compound relative to a number of electrons Np of the (meth)acrylic acid ester compound is 17 or more and 70 or less, and an amount of the surfactant relative to 100 parts by weight of a total of the liquid crystal compound and the (meth)acrylic acid ester compound is 0.11 part by weight or more and 0.29 part by weight or less.