Abstract: The invention aims to provide a method by which a solution of polyimide can be easily obtained. Further, the invention aims to provide a fluorinated polyimide solution by which fluorinated polyimide excellent especially as an optical material and an electronic functional material can easily be produced. The production method of the soluble polyimide solution according to invention is characterized by mixing a mixture containing a polyamide acid, a cyclodehydration reagent, and a solvent by a rotation-revolution mixing method. Further, the fluorinated polyimide solution of the invention is a solution of polyimide defined by the following formula (II): wherein, X and Y independently represent divalent organic groups; Z represents chlorine atom, bromine atom, or iodine atom; p represents an integer of 1 to 3; q represents an integer of 0 to 2; and p+q=3.

Abstract: An optical waveguide substrate with an optical fiber fixation groove, including an optical waveguide which contains a lower cladding layer on a base substrate, wherein the lower cladding layer has an optical fiber fixation groove and a core groove, and a weir is provided between the optical fiber fixation groove and the core groove. The optical waveguide substrate with an optical fiber fixation groove is produced by forming a lower cladding layer on a base substrate using a male stamp produced from a female stamp and then successively forming a core layer and an upper cladding layer thereon.

Abstract: Provided are a polyimide which is inexpensive, has various excellent material properties including strength, heat resistance, low moisture absorption, mold releasability (detachability), dielectric properties, electrical properties, and optical properties, and can exhibit a high level of water repellency, and a polyamic acid composition useful as a raw material therefor. Also provided are the polyimide which can give a polyimide composition that, besides having such excellent material properties, is capable of having a controlled surface resistivity, and a polyamic acid composition useful as a raw material therefor.

Abstract: The invention provides a flexible optical waveguide in which an optical waveguide film is directly formed on a substrate without using an adhesive and which is excellent in flexibility of the optical waveguide film, including the substrate, and excellent in adhesiveness between the substrate and the optical waveguide film, as well as a process for producing the flexible optical waveguide in a simple and easy manner. The flexible optical waveguide includes a lower cladding layer, a core layer, and an upper cladding layer successively formed on a substrate and a surface of the substrate, on which surface the lower cladding layer is to be formed, has an arithmetic average roughness (Ra) of 0.03 ?m or higher.

Abstract: The present invention provides a light selective transmission filter which selectively shields light and has a high transmittance of light at a specific wavelength such as visible rays, and which has a sufficiently reduced thickness and excellent heat resistance. The present invention further provides a lens unit including such a light selective transmission filter. The light selective transmission filter selectively reducing a transmittance of light has a thickness of less than 200 ?m and includes a base material containing a functional film with reflow resistance. The lens unit includes such a light selective transmission filter and a lens.

Abstract: In an optical waveguide, the present invention provides a process for producing an optical waveguide, and a stamp for use in the production process, in which the thickness of a lower cladding layer in the portion positioned in the lower side of a core layer is easily controlled even if any one or more materials of a substrate, a cladding material, and a stamp are material with low rigidity. The production process of the present invention comprises steps of forming a lower cladding layer which has a core groove and spacer grooves formed substantially in parallel with intervals in both sides of the core groove on a substrate by making use of soft lithography with a second stamp (i.e.

Abstract: The invention aims to provide a method by which a solution of polyimide can be easily obtained. Further, the invention aims to provide a fluorinated polyimide solution by which fluorinated polyimide excellent especially as an optical material and an electronic functional material can easily be produced. The production method of the soluble polyimide solution according to invention is characterized by mixing a mixture containing a polyamide acid, a cyclodehydration reagent, and a solvent by a rotation-revolution mixing method. Further, the fluorinated polyimide solution of the invention is a solution of polyimide defined by the following formula (II): wherein, X and Y independently represent divalent organic groups; Z represents chlorine atom, bromine atom, or iodine atom; p represents an integer of 1 to 3; q represents an integer of 0 to 2; and p+q=3.

Abstract: The present invention provides a flexible optical waveguide in which at least one of a lower cladding layer, a core layer, and an upper cladding layer is composed of an epoxy film formed using an epoxy resin composition containing a polyglycidyl compound having a polyalkylene glycol chain(s) and at least two glycidyl groups or an epoxy film having a glass transition temperature (Tg) of 100° C. or lower, a process for its production, and an epoxy resin composition for flexible optical waveguides.

Abstract: An optical waveguide substrate with an optical fiber fixation groove, including an optical waveguide which contains a lower cladding layer on a base substrate, wherein the lower cladding layer has an optical fiber fixation groove and a core groove, and a weir is provided between the optical fiber fixation groove and the core groove. The optical waveguide substrate with an optical fiber fixation groove is produced by forming a lower cladding layer on a base substrate using a male stamp produced from a female stamp and then successively forming a core layer and an upper cladding layer thereon. The stamp for use in such a production process includes concave portions or convex portions, corresponding to the optical fiber fixation groove and the core groove, as well as a convex portion or a concave portion corresponding to the weir. An opto-electronic hybrid integrated module includes the optical waveguide substrate with an optical fiber fixation groove.

Abstract: The invention provides a flexible optical waveguide in which an optical waveguide film is directly formed on a substrate without using an adhesive and which is excellent in flexibility of the optical waveguide film, including the substrate, and excellent in adhesiveness between the substrate and the optical waveguide film, as well as a process for producing the flexible optical waveguide in a simple and easy manner. The flexible optical waveguide includes a lower cladding layer, a core layer, and an upper cladding layer successively formed on a substrate and a surface of the substrate, on which surface the lower cladding layer is to be formed, has an arithmetic average roughness (Ra) of 0.03 ?m or higher.

Abstract: To provide to a resin composition for an optical packaging material having a coefficient of thermal expansion approximately same as that of quartz and Pyrex (registered trade name) and capable of providing an optical packaging material exhibiting excellent flame retardancy and an optical packaging component, and an optical module and its production method. A molded body, an optical packaging component and an optical module having a low coefficient of thermal expansion and excellent flame retardancy can be obtained using a resin composition for an optical packaging material comprising a resin and inorganic fine particles which are made of a hydrolyzed condensate compound of an alkoxide compound and/or a carboxylic acid salt compound and have an average radius of gyration of 50 nm or smaller.

Abstract: A halogenated polyamide acid composition containing a halogenated polyamide acid, a metal oxide precursor, a catalyst of reaction of generating a metal oxide from the precursor, and/or a coupling agent having a reactive group. A halogenated polyimide film is obtained by, for example, carrying out the heat treatment of the halogenated polyamide acid composition. The halogenated polyimide film has a refractive index at wavelength of, for example, 1,550 nm of 1.520 or lower. Further, an optical waveguide uses the halogenated polyimide film as at least one of a core layer and a clad layer, and a relative refractive index difference between the core layer and the clad layer of the optical waveguide is, for example, 0.6 or greater. An optical waveguide device contains such an optical waveguide.

Abstract: The present invention provides a light selective transmission filter which selectively shields light and has a high transmittance of light at a specific wavelength such as visible rays, and which has a sufficiently reduced thickness and excellent heat resistance. The present invention further provides a lens unit including such a light selective transmission filter. The light selective transmission filter selectively reducing a transmittance of light has a thickness of less than 200 ?m and includes a base material containing a functional film with reflow resistance. The lens unit includes such a light selective transmission filter and a lens.

Abstract: A method for producing a fluorine-containing polyimide film excelling in heat resistance, resistance to chemicals, water repellency, dielectric properties, electrical properties, and optical properties and a spin coater suitable for the method are to be provided. A method for the production of a fluorine-containing polyimide film which comprises forming a coating film of a fluorine-containing polyimide precursor in an atmosphere having a relative humidity thereof adjusted to a level of not more than 50 RH % and then subjecting the fluorine-containing polyimide precursor to heat treatment thereby forming a fluorine-containing polyimide film is provided. By adjusting the relative humidity in accordance with this method, the fluorine-containing polyimide precursor can be prevented from being decomposed by the absorption of moisture and consequently prevent effectively the fluorine-containing polyimide film from forming piriform spots and scratches.

Abstract: A halogenated polyamide acid composition containing a halogenated polyamide acid, a metal oxide precursor, a catalyst of reaction of generating a metal oxide from the precursor, and/or a coupling agent having a reactive group. A halogenated polyimide film is obtained by, for example, carrying out the heat treatment of the halogenated polyamide acid composition. The halogenated polyimide film has a refractive index at wavelength of, for example, 1,550 nm of 1.520 or lower. Further, an optical waveguide uses the halogenated polyimide film as at least one of a core layer and a clad layer, and a relative refractive index difference between the core layer and the clad layer of the optical waveguide is, for example, 0.6 or greater. An optical waveguide device contains such an optical waveguide.

Abstract: A fluorinated polyamide acid resin composition for optical materials containing a fluorinated polyamide acid and a non-polycondensable compound (A) with an aromatic ring having a boiling point of 340° C. or lower, the resin composition being used for obtaining a fluorinated polyimide membrane by a baking process. This fluorinated polyamide acid resin composition for optical materials contains a non-polycondensable compound (A) which was found to reduce a light absorption at 1.49 ?m and a light absorption at 1.35 ?m and extending to visible light, even if the baking temperature is 340° C. or lower.

Abstract: The present invention discloses an ink-jet recording sheet which, on at least one surface of a support, has a porous ink absorbing layer containing fine particle silica having the average particle size of 0.5 ?m or smaller produced by wet process, electrolytes such as alkaline metal salts and alkaline earth metal salts, and polyvinyl alcohol; and then has a gloss layer. The ink-jet recording sheet has excellent features, that is, it has gloss like that of photographic printing paper, the excellent ink absorption speed and ink absorption capacity, and does not produce defects of the coating due to the cracks generated during drying in production processes of the ink absorbing layer. Therefore, the ink-jet recording sheet is suitable as a recording sheet for an ink-jet printer.

Abstract: A polyimide excelling in heat resistance, chemical resistance, water repellency, dielectric characteristics, electrical characteristics, and optical characteristics and a polyamide acid useful as the raw material therefor are provided. Specifically, a polyamide acid containing a chlorine atom and a fluorine atom and comprising a repeating unit represented by the following formula (1): (wherein X and X? independently denote a divalent organic group; Y and Y? independently denote a chlorine, bromine, or iodine atom; p and p? denote independently denote the number of fluorine atom {F in the formula (1)} bonded to the relevant benzene ring, representing an integer of 0-3; q and q? independently denote an integer of 0-3; and p+q total 3, and p?+q? total 3).

Abstract: A method for producing a fluorine-containing polyimide film excelling in heat resistance, resistance to chemicals, water repellency, dielectric properties, electrical properties, and optical properties and a spin coater suitable for the method are to be provided. A method for the production of a fluorine-containing polyimide film which comprises forming a coating film of a fluorine-containing polyimide precursor in an atmosphere having a relative humidity thereof adjusted to a level of not more than 50 RH % and then subjecting the fluorine-containing polyimide precursor to heat treatment thereby forming a fluorine-containing polyimide film is provided. By adjusting the relative humidity in accordance with this method, the fluorine-containing polyimide precursor can be prevented from being decomposed by the absorption of moisture and consequently prevent effectively the fluorine-containing polyimide film from forming piriform spots and scratches.

Abstract: The present invention provides a dispersion of silica particle agglomerates having a sharp particle size distribution and capable of forming a porous coating film having a high transparency by drying.