Abstract: A silica glass for a radio-frequency device has an OH group concentration being less than or equal to 300 wtppm; an FQ value being higher than or equal to 90,000 GHz at a frequency of higher than or equal to 25 GHz and lower than or equal to 30 GHz; and a slope being greater than or equal to 1,000 in a case where the FQ value is approximated as a linear function of the frequency in a frequency band of higher than or equal to 20 GHz and lower than or equal to 100 GHz.

Abstract: One embodiment of the present invention relates to a hard coat film including a first layer in which a polymer of a polymerizable composition containing at least one polyfunctional polymerizable compound having two or more polymerizable groups in one molecule is detected as a main component and an organic solvent-soluble resin is not detected by composition analysis using a RAMAN spectroscopy; and a second layer adjacent to the first layer, in which an organic solvent-soluble resin and a polymer of a polymerizable composition containing at least one polyfunctional polymerizable compound having two or more polymerizable groups in one molecule are detected by the composition analysis, and a thickness is greater than 15 ?m. Further, the present invention relates to a polarizing plate, an image display device, and a method for producing the hard coat film.

Abstract: Provided is a polarizing film showing high dichroism comprising a substrate, and a photo alignment film and a light absorption anisotropic film laminated on the substrate in this order. The light absorption anisotropic film is obtained by fixing the alignment of a dichroic dye composition comprising at least one nematic liquid crystalline azo dichroic dye and in X-ray diffraction measurement thereof, diffraction peaks derived from periodic structure along a vertical direction to the alignment axis are present, the period indicated by at least one of the diffraction peaks is 3.0 to 15.0 ? and an intensity of the diffraction peak does not show a maximum value in the range of ±70° of the film normal line direction in a plane vertical to the alignment axis.

Abstract: One embodiment of the present invention relates to a hard coat film including a first layer in which a polymer of a polymerizable composition containing at least one polyfunctional polymerizable compound having two or more polymerizable groups in one molecule is detected as a main component and an organic solvent-soluble resin is not detected by composition analysis using a RAMAN spectroscopy; and a second layer adjacent to the first layer, in which an organic solvent-soluble resin and a polymer of a polymerizable composition containing at least one polyfunctional polymerizable compound having two or more polymerizable groups in one molecule are detected by the composition analysis, and a thickness is greater than 15 ?m. Further, the present invention relates to a polarizing plate, an image display device, and a method for producing the hard coat film.

Abstract: Provided is a polarizing film showing high dichroism comprising a substrate, and a photo alignment film and a light absorption anisotropic film laminated on the substrate in this order. The light absorption anisotropic film is obtained by fixing the alignment of a dichroic dye composition comprising at least one nematic liquid crystalline azo dichroic dye and in X-ray diffraction measurement thereof, diffraction peaks derived from periodic structure along a vertical direction to the alignment axis are present, the period indicated by at least one of the diffraction peaks is 3.0 to 15.0 ? and an intensity of the diffraction peak does not show a maximum value in the range of ±70° of the film normal line direction in a plane vertical to the alignment axis.

Abstract: A polarizing film comprising a substrate, and a photo alignment film and a light absorption anisotropic film laminated on the substrate in this order, wherein the light absorption anisotropic film has a content ratio of 30% by mass or less of a liquid crystalline non-colorable low molecular weight compound and is obtained by fixing the alignment of a dichroic dye composition comprising at least one nematic liquid crystalline azo dichroic dye; in X-ray diffraction measurement thereof, diffraction peaks derived from periodic structure along a vertical direction to the alignment axis are present, the period indicated by at least one of the diffraction peaks is 3.0 to 15.0 ? and an intensity of the diffraction peak does not show a maximum value in the range of ±70° of the film normal line direction in a plane vertical to the alignment axis.

Abstract: A light absorption anisotropic film, having at least one dichroic dye, in which the light absorption anisotropic film shows a diffraction peak derived from a periodic structure in a direction in a plane of the light absorption anisotropic film in X-ray diffraction measurement and the diffraction peak has a half width of 1.0 ? or less.

Abstract: A light absorption anisotropic film, wherein content of a liquid crystalline non-colorable low molecular weight compound is 30% by mass or less; and which is obtained by fixing the alignment of a dichroic dye composition comprising at least one type of azo-based dichroic dye having nematic liquid crystallinity; and shows a diffraction peak derived from a periodic structure in a direction parallel to the alignment axis on measurement of X-ray diffraction. The light absorption anisotropic film is high in dichroism.

Abstract: A light absorption anisotropic film, wherein content of a liquid crystalline non-colorable low molecular weight compound is 30% by mass or less; and which is obtained by fixing the alignment of a dichroic dye composition comprising at least one type of azo-based dichroic dye having nematic liquid crystallinity; and shows a diffraction peak derived from a periodic structure in a direction parallel to the alignment axis on measurement of X-ray diffraction. The light absorption anisotropic film is high in dichroism.

Abstract: A polarizing film comprising a substrate, and a photo alignment film and a light absorption anisotropic film laminated on the substrate in this order, wherein the light absorption anisotropic film has a content ratio of 30% by mass or less of a liquid crystalline non-colorable low molecular weight compound and is obtained by fixing the alignment of a dichroic dye composition comprising at least one nematic liquid crystalline azo dichroic dye; in X-ray diffraction measurement thereof, diffraction peaks derived from periodic structure along a vertical direction to the alignment axis are present, the period indicated by at least one of the diffraction peaks is 3.0 to 15.0A and an intensity of the diffraction peak does not show a maximum value in the range of ±70° of the film normal line direction in a plane vertical to the alignment axis.

Abstract: A light absorption anisotropic film, having at least one dichroic dye, in which the light absorption anisotropic film shows a diffraction peak derived from a periodic structure in a direction in a plane of the light absorption anisotropic film in X-ray diffraction measurement and the diffraction peak has a half width of 1.0 ? or less.