Patents by Inventor Aiko Okamura

Aiko Okamura 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).

  • Aqueous pigment ink composition
    Patent number: 5861447
    Abstract: An aqueous pigment ink composition comprising an oxidized carbon black obtained by wet-oxidation of a carbon black using a hypohalous acid and/or salt thereof, and a water-soluble cationic polymer or oligomer in an aqueous medium. The aqueous pigment ink composition of the present invention does not cause clogging in a nozzle when used for ink jet recording, enables smooth writing from a narrow pen tip, and provides a recorded image excellent in water resistance and light resistance and excellent in density and hue.
    Type: Grant
    Filed: July 18, 1997
    Date of Patent: January 19, 1999
    Assignee: Orient Chemical Industries, Ltd.
    Inventors: Toshiyuki Nagasawa, Sohko Itoh, Aiko Okamura