Patents by Inventor Takeaki Oouti

Takeaki Oouti 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).

  • Developer for electrophotography
    Patent number: 5266433
    Abstract: A two-component developer for electrophotography includes a toner comprising toner particles and an external additive composed of a compound of imidazole series or an imidazole derivative. The external additive has a volume median particle size below that of the toner particles, or of 0.1 to 100 .mu.m. The amount of external additive is 0.001 to 5% by weight based on the weight of the toner particles. As a result, scattering of toner may be prevented and the formation of fog in the background may be reduced. In addition, the electrostatic charge characteristics of the toner may be improved and the electrostatic charge rises in a satisfactory manner.
    Type: Grant
    Filed: December 7, 1990
    Date of Patent: November 30, 1993
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshihisa Ishida, Tadashi Nakamura, Nobuhiko Nakano, Kanshiro Okamoto, Takeaki Oouti, Shintaro Hatano