Patents by Inventor Sadamu Hirakawa

Sadamu Hirakawa 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).

  • Patent number: 6448357
    Abstract: A polyolefin resin composition comprising (A) an ethylene-based polyolefin having a density of 0.865 to 0.980 g/cm3 and MFR of 0.01 to 50 g/10 min, (B) a phosphorous compound, and (C) at least one heat stabilizer selected from the group consisting of a phenol-based heat stabilizer and a tocopherol-based heat stabilizer. The polyolefin resin composition has excellent heat resistance, moisture resistance and discoloration resistance, and also when used as a packaging material, does not impair the taste of contents to be packaged, such as flavor or odor, and therefore does not impair the taste of the contents.
    Type: Grant
    Filed: July 14, 2000
    Date of Patent: September 10, 2002
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Naoshi Hamada, Sadamu Hirakawa, Akihiko Yamamoto
  • Patent number: 6110549
    Abstract: A sealant resin composition for retort packaging film comprises a high density polyethylene as the main resin component and a linear low density polyethylene polymerized by use of the metallocene catalyst. A sealant film produced therefrom is resistant to whitening, heat fusion, heat deformation after being subjected to boiling sterilization treatment and prevent breakage of pouches produced therefrom even at low temperatures because of its high impact strength and heat sealing strength.
    Type: Grant
    Filed: April 30, 1998
    Date of Patent: August 29, 2000
    Assignee: Mitsui Chemicals Inc.
    Inventors: Naoshi Hamada, Sadamu Hirakawa, Shigeo Ozaki
  • Patent number: 5308573
    Abstract: A method of molding a fuel tank wherein two baffle plates mounted on a blow-in are inserted in a molten parison of a thermoplastic resin surrounded by a split metal mold. The split metal mold is closed around the parison and a pressurized fluid is fed through the blow-in into the molten parison to blow-mold the fuel tank. The baffle plates, during the blow-molding, are melt-adhered onto the inner wall of the fuel tank. A blow-molded fuel tank containing two baffle plates adhered to the inner wall of the fuel tank is obtained.
    Type: Grant
    Filed: August 5, 1992
    Date of Patent: May 3, 1994
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventor: Sadamu Hirakawa