Patents by Inventor Tatsuhiko Niwa

Tatsuhiko Niwa 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).

  • Process for polymerizing vinyl chloride
    Patent number: 4145499
    Abstract: Disclosed is a process for polymerizing vinyl chloride, alone or in combination with a comonomer, in the vapor phase maintained at a pressure lower than the vapor pressure of the monomer at the polymerization temperature employed, and in the presence of the specified seed vinyl chloride polymer particles. The seed polymer particles used are prepared by polymerizing vinyl chloride, along or in combination with a comonomer, under bulk conditions, in the presence of 0.001% to 2% by weight, based on the weight of the monomer, of a cellulose ether soluble in the monomer.
    Type: Grant
    Filed: April 28, 1978
    Date of Patent: March 20, 1979
    Assignee: Toyo Soda Manufacturing Co., Ltd.
    Inventors: Mineo Nagano, Shigeru Awazawa, Tatsuhiko Niwa