Nippon Shokubai Co., Ltd.

Hitachi Cable, Inc.

Ntt Advanced Technology Corporation

Kozo Tajiri

Tomomi Makino

Yoshinobu Asako

Koki Hirano

Takami Ushiwata

Sadao Miki

Seiichi Teshima

Yoko Matsui

Shinichi Goto

Masayoshi Konishi

Yasunori Okumura

Junichi Nakamura

Yasunori Tsujino

Ai Matsumoto

Go Masuda

Tohru Matsuura

Masayoshi Kuwabara

Tatsushi Hirauchi

Noriyoshi Yamada

Shinpei Sato

Keiko Ando

Kumiko Kawada

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.

Production method of polyimide solution and fluorinated polyimide solution

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.

Optical waveguide substrate with optical fiber fixation groove, process for its production, stamps for use in this production process, and opto-electronic hybrid integrated module including said optical waveguide substrate

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 &#x3bc;m or higher. The flexible optical waveguide can be produced by subjecting a surface of the substrate, on which surface the lower cladding layer is to be formed, to physical treatment with a whetstone or chemical treatment with a corona discharge and then successively forming the lower cladding layer, the core layer, and the upper cladding layer on the surface of the substrate.

Flexible optical waveguide and process for its production

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 &#x3bc;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.

Light selective transmission filter

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.

Halogenated polyamide acid composition and its applications

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. Further, by forming the coating film while keeping the coating film sprayed with a gas particularly during the course of spin coating thereby giving rise to a layer of air flow on the coating film, misty substances of the coating solution generated within the spin coater can be prevented from adhering again to the coating film and consequently ensure the production of a coating film of uniform quality. This formation of the layer of air flow can be facilitated by providing the spin coater with a lid and furnishing the lid with a gas feed port.

Method and apparatus for production of fluorine-containing polyimide film

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&#x2032; independently denote a chlorine, bromine, or iodine atom; p and p&#x2032; 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&#x2032; independently denote an integer of 0-3; and p+q total 3, and p&#x2032;+q&#x2032; total 3).

Polyamide acid and polyimide, and optical material

Method for production of halogen-containing aromatic compound

This invention relates to a method for the production of an aromatic compound (II) having a (CH,),CX,Br group (wherein X represents a fluorine or chlorine atom and the X's may be same or different, and n is an integer in the range of 0 to 4) by the reaction of photo-bromination of an aromatic compound (I) having a (CH,),CX,H group (wherein X and n are as defined above) with a brominating agent, wherein the photo-bromination reaction is carried out while removing hydrogen bromide generated in the reaction system and/or in an atmosphere of a low oxygen content, and a halogen-containing naphthalene compound represented by the following formula (1):

Growing community of inventors

Sanda, Japan

Kozo Tajiri