Patents by Inventor Hirokuni Kawashima

Hirokuni Kawashima 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).

  • Process for preparing photoconductive cadmium sulfide
    Patent number: 4415643
    Abstract: A process for preparing photoconductive cadmium sulfide comprising steps of forming precipitated cadmium sulfide particles, primarily firing said cadmium sulfide particles, deionizing said cadmium sulfide particles, and secondarily firing said cadmium sulfide particles.
    Type: Grant
    Filed: August 27, 1981
    Date of Patent: November 15, 1983
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koji Goto, Isamu Kajita, Ichiro Nomura, Hirokuni Kawashima
  • Process for preparing cadmium sulfide for electrophotography and product thereof
    Patent number: 4382917
    Abstract: Cadmium sulfide particles are heated in a solution of a compound capable of generating sulfur when heated. The cadmium sulfide thus treated is suitable for a photoconductive material for electrophotography.
    Type: Grant
    Filed: December 23, 1980
    Date of Patent: May 10, 1983
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kiyoshi Suzuki, Hirokuni Kawashima
  • Electrophotosensitive element has resin encapsulated CdS particles in binding resin
    Patent number: 4335195
    Abstract: An electrophotosensitive member having a photoconductive layer prepared by dispersing in a binding resin, photoconductive powder particles coated with a thermoplastic resin. By the use of the such photoconductive powder particles coated with the resin, there can be provided an electrophotosensitive member particularly excellent in the moisture resistant property.
    Type: Grant
    Filed: August 4, 1980
    Date of Patent: June 15, 1982
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yuji Nishigaki, Hirokuni Kawashima
  • Cadmium sulfide for electrophotography
    Patent number: 4316947
    Abstract: Cadium sulfide for electrophotography is produced by reacting hydrogen sulfide with a solution containing cadmium sulfate, sulfuric acid and hydrochloric acid of a low concentration, and then firing the resulting cadmium sulfide without adding a donor impurity other than that derived from the hydrochloric acid.
    Type: Grant
    Filed: September 8, 1980
    Date of Patent: February 23, 1982
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kiyoshi Suzuki, Hirokuni Kawashima
  • Electrophotographic photoreceptor
    Patent number: 4264696
    Abstract: An electrophotographic photoreceptor has a photoconductive layer on a substrate. The photoconductive layer comprises a photoconductor and a water-soluble compound which reacts with free anion released from the photoconductor to produce an unsoluble salt and contains anion having smaller equivalent ionic conductance than that of the free anion.
    Type: Grant
    Filed: April 23, 1979
    Date of Patent: April 28, 1981
    Assignee: Kasei Optonix, Ltd.
    Inventors: Hirokuni Kawashima, Kiyoshi Suzuki, Yoshiyuki Mimura, Kunihiko Yoneshima
  • Process for preparing raw particles of cadmium sulfide for electrophotography
    Patent number: 4197122
    Abstract: A process for preparing raw particles of cadmium sulfide for electrophotography comprises reacting a solution containing cadmium ion and hydrochloric acid with hydorgen sulfide to make cadmium sulfide particles deposited from the solution.
    Type: Grant
    Filed: April 29, 1977
    Date of Patent: April 8, 1980
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirokuni Kawashima, Kiyoshi Suzuki
  • Process for producing cadmium sulfide for electrophotography
    Patent number: 4021237
    Abstract: CdS for electrophotography is produced by contacting sulfide ion, cadmium ion and a donor impurity of Group IIIa or IIIb of the Periodic Table and firing the resulting CdS. An acceptor impurity may be added to the first step or the second step.
    Type: Grant
    Filed: November 14, 1974
    Date of Patent: May 3, 1977
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirokuni Kawashima, Kiyoshi Suzuki