Patents by Inventor Yaosuo Kitabatake

Yaosuo Kitabatake 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: 4859560
    Abstract: A method of producing toner particles for use in electrophotography where the particles have a colored resin core particle containing a resin and a colorant and charge controlling layer on the particle's outer surface. The charge controlling layer contains a charge controlling agent but not any colorant. The method comprises the steps of:(1) preparting toner core particles by mixing, kneading, crushing and sorting a first material including a resin material and a colorant,(2) preparing charge controlling particles with smaller diameters than the toner core particles by mixing, kneading, crushing and sorting a second material including a charge controlling agent, and(3) thereafter mixing the toner core particles the said charge controlling particles and causing a charge controlling layers to be formed around the toner core particles by applying a pressure to the mixed particles.
    Type: Grant
    Filed: October 9, 1987
    Date of Patent: August 22, 1989
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Tadashi Nakamura, Yaosuo Kitabatake, Yoshiaki Takahashi, Kazuya Maeda