Patents by Inventor Eiji Y. Yamamoto

Eiji Y. Yamamoto 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).

  • Light-weight polyester film and process for its production
    Patent number: 5204418
    Abstract: A light-weight polyester film which comprises (A) from 50 to 95% by weight of a crystalline polyester resin and (B) from 5 to 50% by weight of a maleimide copolymer, said maleimide copolymer being dispersed in the film in the form of particles having diameters of from 0.1 to 20 .mu.m and fine voids being present in the film, and which has an apparent specific gravity of from 0.3 to 1.1, wherein said maleimide copolymer comprises from 30 to 50 mol % of a maleimide monomer group, from 30 to 70 mol % of an aromatic vinyl monomer group, from 0 to 40 mol % of an unsaturated dicarboxylic anhydride monomer group and from 0 to 40 mol % of other copolymerizable monomer group, and said maleimide copolymer has a glass transition temperature higher by at least 10.degree. C. than the crystalline polyester resin.
    Type: Grant
    Filed: January 30, 1992
    Date of Patent: April 20, 1993
    Assignee: Unitika Ltd.
    Inventors: Kenji Yasue, Eiji Y. Yamamoto, Katsuyuki Toma, Minoru Kishida, Yoshiaki Kozuka