Patents by Inventor Takehiko Narisada

Takehiko Narisada 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 producing methyl methacrylate polymers
    Patent number: 3968059
    Abstract: A process of producing methyl methacrylate polymers is provided wherein the monomer are polymerized by a bulk polymerization procedure at 150.degree. to 180.degree.C with a conversion of 50 to 80% and the volatiles predominantly comprised of the unreacted monomer, separated from the polymer product, are cyclically reused as a part of the monomer feed for polymerization. In such a monomer feed cycle system, oligomers are substantially removed from the volatiles and then the volatiles are blended with a virgin monomer feed for polymerization, the content in the volatiles of impurities having boiling points of lower than 200.degree.C at normal pressure is maintained within the range of 5 to 20% by weight.
    Type: Grant
    Filed: February 4, 1975
    Date of Patent: July 6, 1976
    Assignee: Mitsubishi Rayon Co., Ltd.
    Inventors: Kazushi Shimada, Toru Maeda, Tamotu Nishizawa, Yositaka Sasaki, Takehiko Narisada, Hisao Anzai