Abstract: To obtain a water-resistant polarizing film free from deterioration in dichroic ratio caused by water-resistant treatment, it is critical that adjacent sulfonic acid groups or sulfonate groups in the organic dyes to be used for the polarizing film are spaced at moderate intervals.

Abstract: There is provided a method for producing a polarizing film having far superior water resistance to conventional polarizing films by contacting a liquid containing cationic polymers with a surface of a polarizing film.

Abstract: To obtain a water-resistant polarizing film free from deterioration in dichroic ratio caused by water-resistant treatment, it is critical that adjacent sulfonic acid groups or sulfonate groups in the organic dyes to be used for the polarizing film are spaced at moderate intervals.

Abstract: There is provided a method for manufacturing a thin polarizing film having an absorption axis oblique to a width direction of the film which comprises the steps of: performing an orientation treatment in two directions in a plane of a support film; applying a solution containing a lyotropic liquid crystal compound onto a surface of the support film; and causing a column-shaped aggregate of the lyotropic liquid crystal compound to be oriented in a direction (orientation direction) equal to the vector sum of a direction of first orientation treatment and a direction of second orientation treatment.

Abstract: To obtain a water-resistant polarizing film free from deterioration in dichroic ratio caused by water-resistant treatment, it is critical that adjacent sulfonic acid groups or sulfonate groups in the organic dyes to be used for the polarizing film are spaced at moderate intervals.

Abstract: A birefringent film of the present invention comprises at least one kind of polycyclic compound including a —COOM group (the M denotes a counter ion), wherein an index ellipsoid satisfies a relation of nz>nx=ny. The polycyclic compound includes, for example, acenaphtho[1,2-b]quinoxaline derivative represented by the following general formula (I). The birefringent film of the present invention can be formed thin-type and have a high birefringent index in the thickness direction, since the birefringent film comprises the polycyclic compound.

Abstract: There is provided a method for manufacturing a thin polarizing film having an absorption axis oblique to a width direction of the film which comprises the steps of: performing an orientation treatment in two directions in a plane of a support film; applying a solution containing a lyotropic liquid crystal compound onto a surface of the support film; and causing a column-shaped aggregate of the lyotropic liquid crystal compound to be oriented in a direction (orientation direction) equal to the vector sum of a direction of first orientation treatment and a direction of second orientation treatment.

Abstract: Provided is a production method for a thin birefringent film with a satisfactory alignment property, in which a refractive index is controlled three-dimensionally and optical properties are unlikely to decrease in the case where the birefringent film is placed under high temperature and high humidity. The production method for a birefringent film of the present invention includes: the step (1) of preparing a solution that exhibits a nematic liquid crystal phase, containing at least one kind of polycyclic compound containing a —SO3M group and/or a —COOM group (M represents a counter ion) and a solvent; the step (2) of preparing a base material at least one surface of which is subjected to a hydrophilization treatment; and the step (3) of applying the solution prepared in the step (1) to the surface of the base material prepared in the step (2), the surface being subjected to the hydrophilization treatment, followed by drying, in which a contact angle of water at 23° C.

Abstract: There is provided a method for producing a polarizing film having far superior water resistance to conventional polarizing films by contacting a liquid containing cationic polymers with a surface of a polarizing film.

Abstract: To obtain a water-resistant polarizing film free from deterioration in dichroic ratio caused by water-resistant treatment, it is critical that adjacent sulfonic acid groups or sulfonate groups in the organic dyes to be used for the polarizing film are spaced at moderate intervals.

Abstract: The present invention provides a birefringent film that hardly generates cracks even when the film is exposed under a high-temperature and high-humidity environment for a long period of time. The birefringent film of the present invention is a film containing, as a major component, a lyotropic liquid crystalline polycyclic compound containing an acenaphtho[1,2-b]quinoxaline derivative unit in a molecular structure and having a molecular weight of 500 or higher. The birefringent film of the present invention preferably has a refractive index ellipsoid showing a relationship of nx?nz>ny, and more preferably has an in-plane birefringence of 0.01 or higher at the wavelength of 590 nm.

Abstract: The present invention provides a thin and light-weight birefringent film having a desired Nz coefficient, such that an index ellipsoid satisfies a relationship of nx?nz>ny. The birefringent film of the present invention contains a first acenaphtho[1,2-b]quinoxaline derivative exhibiting lyotropic liquid crystallinity and a second acenaphtho[1,2-b]quinoxaline derivative exhibiting lyotropic liquid crystallinity, wherein an index ellipsoid satisfies a relationship of nx?nz>ny. An Nz coefficient of this birefringent film is preferably 0 to 0.5.

Abstract: Provided is a production method for a thin birefringent film with a satisfactory alignment property, in which a refractive index is controlled three-dimensionally and optical properties are unlikely to decrease in the case where the birefringent film is placed under high temperature and high humidity. The production method for a birefringent film of the present invention includes: the step (1) of preparing a solution that exhibits a nematic liquid crystal phase, containing at least one kind of polycyclic compound containing a —SO3M group and/or a —COOM group (M represents a counter ion) and a solvent; the step (2) of preparing a base material at least one surface of which is subjected to a hydrophilization treatment; and the step (3) of applying the solution prepared in the step (1) to the surface of the base material prepared in the step (2), the surface being subjected to the hydrophilization treatment, followed by drying, in which a contact angle of water at 23° C.

Abstract: A birefringent film of the present invention comprises at least one kind of polycyclic compound including a —COOM group (the M denotes a counter ion), wherein an index ellipsoid satisfies a relation of nz>nx=ny. The polycyclic compound includes, for example, acenaphtho[1,2-b]quinoxaline derivative represented by the following general formula (I). The birefringent film of the present invention can be formed thin-type and have a high birefringent index in the thickness direction, since the birefringent film comprises the polycyclic compound.

Abstract: Provided is very thin liquid crystal panel and liquid crystal display apparatus with a high contrast ratio in an oblique direction, less light leakage, and a small color shift in an oblique direction. The liquid crystal panel of the present invention includes a liquid crystal cell, a first polarizer arranged on one side of the liquid crystal cell, a second polarizer arranged on the other side of the liquid crystal cell, a first optical element arranged between the first polarizer and the liquid crystal cell, and a second optical element arranged between the first optical element and the liquid crystal cell. The first optical element has substantially optically negative uniaxial property, and the second optical element exhibits a refractive index ellipsoid of nx>nz>ny, and is formed of one or more kinds of polycylic compound having a —SO3M group and/or a —COOM group (M represents a counter ion).

Abstract: Provided are a liquid crystal panel and a liquid crystal display apparatus with a high contrast ratio in an oblique direction, less light leakage, a small color shift in an oblique direction, and extremely small thickness. The liquid crystal panel of the present invention includes a liquid crystal cell, a first polarizer arranged on one side of the liquid crystal cell, an optical element (A), an optical element (B), and a second polarizer arranged on the other side of the liquid crystal cell. The optical element (A) exhibits a refractive index ellipsoid of nx>nz>ny, is formed of a specific polycyclic compound, and has an Nz coefficient of 0.05 to 0.45. The optical element (B) exhibits a refractive index ellipsoid of nx>nz>ny and has an Nz coefficient of 0.55 to 0.95.

Abstract: Provided is a thin birefringent film whose refractive index is three-dimensionally controlled. The present invention provides a birefringent film including at least one polycyclic compound containing a —SO3M group and/or a —COOM group having a refractive index ellipsoid satisfying a relationship represented by nx>nz>ny, in which M represents a counter ion. Since such a birefringent film has a high in-plane refractive index, the thickness thereof is sharply reduced as compared with a conventional birefringent film and a desired retardation value can be obtained.

Abstract: The present invention provides a birefringent film that hardly generates cracks even when the film is exposed under a high-temperature and high-humidity environment for a long period of time. The birefringent film of the present invention is a film containing, as a major component, a lyotropic liquid crystalline polycyclic compound containing an acenaphtho[1,2-b]quinoxaline derivative unit in a molecular structure and having a molecular weight of 500 or higher. The birefringent film of the present invention preferably has a refractive index ellipsoid showing a relationship of nx?nz>ny, and more preferably has an in-plane birefringence of 0.01 or higher at the wavelength of 590 nm.