Patents by Inventor Shuji Watakabe

Shuji Watakabe 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: 5262227
    Abstract: An aromatic polyimide film directly laminated with a metal foil and an aromatic polyimide film directly laminated on both sides with a metal foil wherein the polyimide film (substrate) comprises an aromatic polyimide layer-A of 6-200 .mu.m thick whose polyimide is derived from a biphenyltetracarboxylic acid or its derivative and a phenylenediamine and an aromatic polyimide layer-B of 0.2-15 .mu.m thick whose polyimide is derived from an aromatic tetracarboxylic acid or its derivative and an aromatic diamine having plural benzene rings, and the polyimide layer-A has a thickness of not less than 55% of the total thickness of the aromatic polyimide substrate film, the polyimide layer-B is fixed to the polyimide layer-A under the condition that the layer-B cannot be peeled from the layer-A along the interface between these layers-A and -B and the metal foil is directly fixed on the surface of the polyimide layer-B via no adhesive.
    Type: Grant
    Filed: May 30, 1991
    Date of Patent: November 16, 1993
    Assignee: Ube Industries, Ltd.
    Inventors: Seiichirou Takabayashi, Katsuo Imatani, Kazuaki Mii, Shuji Watakabe