Patents by Inventor Kazuo Ohkouchi

Kazuo Ohkouchi 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).

  • Method for preventing polymerization in an acrylic acid manufacturing process
    Patent number: 7005544
    Abstract: A method for effectively preventing polymerization of acrylic acid during an azeotropic dehydration distillation in an acrylic acid manufacturing process and thus enabling stable operation of the azeotropic dehydration column over an extended period of time. The acrylic acid is separated in an azeotropic dehydration column from an acrylic acid aqueous solution fed therein, and the method includes withdrawing from the bottom of the azeotropie dehydration column a bottom effluent containing 50% or more of glyoxal (including the hydrates thereof) contained in the acrylic acid aqueous solution fed into the azeotropic dehydration column.
    Type: Grant
    Filed: August 29, 2003
    Date of Patent: February 28, 2006
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Kazuo Ohkouchi, Tomohiro Nakae, Kazuhiko Sakamoto
  • Method for producing (meth)acrylic acid
    Patent number: 6888026
    Abstract: An object of this invention is to provide a method for producing acrylic acid that enables to suppress adverse influence of byproducts during distillation and to accomplish long-term continuous operation of the acrylic acid production apparatus. This invention is directed to a method for producing (meth)acrylic acid comprising the step of isolating (meth)acrylic acid from a liquid containing (meth)acrylic acid by distillation wherein the liquid contains glyoxal (including its hydrate) in a concentration of 0.1 mass % or less.
    Type: Grant
    Filed: September 26, 2002
    Date of Patent: May 3, 2005
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Kazuhiko Sakamoto, Kazuo Ohkouchi, Tomohiro Nakae
  • Method for preventing polymerization in an acrylic acid manufacturing process
    Publication number: 20040044120
    Abstract: A method for effective preventing polymerization of acrylic acid during an azeotropic dehydration distillation in an acrylic acid manufacturing process and thus enabling an stable operation of the azeotropic dehydration column over an extended period of time. A method for preventing the polymerization of acrylic acid in an acrylic acid production process, wherein acrylic acid is separated in an azeotropic dehydration column from an acrylic acid aqueous solution fed therein, the method comprising withdrawing from the bottom of the azeotropic dehydration column a bottom effluent containing 50% or more of glyoxal (including the hydrates thereof) contained in the acrylic acid aqueous solution fed into the azeotropic dehydration column.
    Type: Application
    Filed: August 29, 2003
    Publication date: March 4, 2004
    Inventors: Kazuo Ohkouchi, Tomohiro Nakae, Kazuhiko Sakamoto
  • Method for inhibiting polymerization of a vinyl compound
    Patent number: 6664418
    Abstract: A method for inhibiting polymerization during transportation, storage and/or production of (meth)acrylic acid or an ester thereof includes adding an N-oxyl compound and water to a vinyl compound; or dissolving an N-oxyl compound in water and adding the solution to a vinyl compound in a process of recovering, purifying, and/or synthesizing of the vinyl compound. The method can effectively inhibit polymerization of the vinyl compound.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: December 16, 2003
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Kazuhiko Sakamoto, Kazuo Ohkouchi, Masahiro Uemura, Sei Nakahara, Masatoshi Ueoka
  • Method for producing (meth)acrylic acid
    Publication number: 20030065215
    Abstract: An object of this invention is to provide a method for producing acrylic acid that enables to suppress adverse influence of byproducts during distillation and to accomplish long-term continuous operation of the acrylic acid production apparatus. This invention is directed to a method for producing (meth)acrylic acid comprising the step of isolating (meth)acrylic acid from a liquid containing (meth)acrylic acid by distillation wherein the liquid contains glyoxal (including its hydrate) in a concentration of 0.1 mass % or less.
    Type: Application
    Filed: September 26, 2002
    Publication date: April 3, 2003
    Inventors: Kazuhiko Sakamoto, Kazuo Ohkouchi, Tomohiro Nakae