Patents by Inventor Masaharu Kittaka

Masaharu Kittaka has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Crystalline parahydroxybenzoic acid anhydride and process for preparing the same
    Patent number: 7304182
    Abstract: The present invention provides a process for preparing crystalline parahydroxybenzoic acid anhydride, comprising the step of precipitating and isolating parahydroxybenzoic acid in an aqueous solvent at a temperature equal to or above the transition temperature of parahydroxybenzoic acid.
    Type: Grant
    Filed: April 12, 2004
    Date of Patent: December 4, 2007
    Assignee: Kabushiki Kaisha Ueno Seiyaku Oyo Kenkyujo
    Inventors: Ryuzo Ueno, Masaya Kitayama, Nobutaka Izumichi, Masaharu Kittaka
  • Crystal of p-hydroxybenzoic anhydride and process for producing the same
    Publication number: 20060264670
    Abstract: The present invention provides a process for preparing crystalline parahydroxybenzoic acid anhydride, comprising the step of precipitating and isolating parahydroxybenzoic acid in an aqueous solvent at a temperature equal to or above the transition temperature of parahydroxybenzoic acid.
    Type: Application
    Filed: April 12, 2004
    Publication date: November 23, 2006
    Inventors: Ryuzo Ueno, Masaya Kitayama, Nobutaka Izumichi, Masaharu Kittaka
  • Granule of parahydroxybenzoic acid or parahydroxybenzoic ester and process for producing the same
    Patent number: 6673962
    Abstract: Granular product of parahydroxybenzoic acid or its ester which exhibits well suppressed dusting and caking tendency and a process for preparing the product are provided. The granular product of parahydroxybenzoic acid or its ester according to the instant invention has an average particle size of equal to or more than 150 &mgr;m and a hardness of 10-3000 g. The granular product of the invention can be prepared by dry compressing powdery parahydroxybenzoic acid or its ester to give compressed material, pulverizing and classifying the material.
    Type: Grant
    Filed: December 18, 2002
    Date of Patent: January 6, 2004
    Assignee: Kabushiki Kaisha Ueno Seiyaku Oyo Kenkyujo
    Inventors: Ryuzo Ueno, Masaya Kitayama, Nobutaka Izumichi, Masaharu Kittaka
  • Granule of parahydroxybenzoic acid or parahydroxybenzoic ester and process for producing the same
    Publication number: 20030160205
    Abstract: Granular product of parahydroxybenzoic acid or its ester which exhibits well suppressed dusting and caking tendency and a process for preparing the product are provided. The granular product of parahydroxybenzoic acid or its ester according to the instant invention has an average particle size of equal to or more than 150 &mgr;m and a hardness of 10-3000 g. The granular product of the invention can be prepared by dry compressing powdery parahydroxybenzoic acid or its ester to give compressed material, pulverizing and classifying the material.
    Type: Application
    Filed: December 18, 2002
    Publication date: August 28, 2003
    Inventors: Ryuzo Ueno, Masaya Kitayama, Nobutaka Izumichi, Masaharu Kittaka
  • Granules of 2-hydroxynaphthalene-3-carboxylic acid and method for preparing the same
    Patent number: 6562998
    Abstract: Granular product of 2-hydroxynaphthalene-3-carboxylic acid with well-suppressed dusting tendency, and process for preparing the same is provided. Granular product of 2-hydroxynaphthalene-3-carboxylic acid having an average particle size of 150 &mgr;m or more and a hardness of 70-3000 g, and a process for preparing the same comprising the steps of dry compressing powdery 2-hydroxynaphthalene-3-carboxylic acid to give compressed material and pulverizing and classifying the same.
    Type: Grant
    Filed: June 26, 2001
    Date of Patent: May 13, 2003
    Assignee: Kabushiki Kaisha Ueno Seiyako Oyo Kenkyujo
    Inventors: Ryuzo Ueno, Masaya Kitayama, Nobutaka Izumichi, Syungo Nara, Masaharu Kittaka
  • Water-soluble azo compounds and process for the preparation thereof
    Patent number: 6239263
    Abstract: Novel water-soluble azo compounds useful as raw materials for preparing dyes excellent in dyeing properties and fastness and prepared from a coupler consisting of 2-hydroxynaphthalene-3,6-dicarboxylic acid or an ester thereof or an amide derivative of the same and a diazonium compound having a group of the general formula: —B—(CH2)2- Q or —B′—(CH2)2-Q′ (wherein B and B′ are each an electron-attracting group; and Q and Q′ are each a group capable of forming a vinyl group through the elimination with an alkali, provided the groups Q and Q′ are each bonded at the &bgr;-position of the ethyl group).
    Type: Grant
    Filed: August 26, 1999
    Date of Patent: May 29, 2001
    Assignee: Kabushiki Kaisha Ueno Seiyaku Oyo Kenkyujo
    Inventors: Ryuzo Ueno, Masaya Kitayama, Kenji Minami, Masaharu Kittaka
  • Water-soluble azo compounds and process for producing the same
    Patent number: 6020470
    Abstract: The present invention provides novel water-soluble azo compounds derived from 2-hydroxynaphthalene-3,6-dicarboxylic acid or derivatives thereof and diazonium salts having sulfo group(s). These compounds are useful as raw materials for dyes having excellent dyeing properties and fastness.
    Type: Grant
    Filed: March 22, 1999
    Date of Patent: February 1, 2000
    Assignee: Kabushiki Kaisha Ueno Seiyaku Oyo Kenkyujo
    Inventors: Ryuzo Ueno, Masaya Kitayama, Kenji Minami, Masaharu Kittaka