Patents by Inventor Michiaki Ishikawa

Michiaki Ishikawa 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: 5272038
    Abstract: A resin coated carrier for developing an electrostatic image is disclosed. The carrier coating layer comprises a resin copolymerized of at least three fluorinated vinyl monomers. The carrier is useful for developing a negative charged electrostatic image formed on an organic photoreceptor.
    Type: Grant
    Filed: September 10, 1991
    Date of Patent: December 21, 1993
    Assignee: Konica Corporation
    Inventors: Akitoshi Matsubara, Meizo Shirose, Michiaki Ishikawa, Yoshiki Nishimori, Hiroyuki Takagiwa
  • Patent number: 5104762
    Abstract: A developer for electrophotography is disclosed. The developer comprises a carrier comprising magnetic particles being coated with a fluororesin in which an alkali salt of a fatty acid is contained in an amount of from 0.05 to 0.5% by weight of said carrier, and a toner comprising a colored particle comprising a colorant and a reaction product of a styrene-acryl copolymer having carboxyl groups with a multivalent metal compound, and an inorganic particle containing an ammonium salt-modified polysiloxane. The developer is excellent in the reproducibility of fine line, the density uniformity of solid image and the fine line-reproducibility in copies formed by successive generations and the durability.
    Type: Grant
    Filed: January 22, 1991
    Date of Patent: April 14, 1992
    Assignee: Konica Corporation
    Inventors: Meizo Shirose, Hiroyuki Takagiwa, Michiaki Ishikawa, Yoshiki Nishimori
  • Patent number: 5093220
    Abstract: An electrostatic latent image developer that is composed of at least three components, toner resin particles containing at least a colorant, carrier particles and fine inorganic particles is disclosed. The improved feature of the developer is that said toner resin particles contain a resin crosslinked with a divalent metal or metals of higher valency and that said fine inorganic particles are surface-treated with an ionic silicone compound.
    Type: Grant
    Filed: January 5, 1990
    Date of Patent: March 3, 1992
    Assignee: Konica Corporation
    Inventors: Hiroya Masaki, Meizo Shirose, Michiaki Ishikawa, Hiroyuki Takagiwa
  • Patent number: 5026620
    Abstract: A method for forming an electrophotographic image, comprising forming an electrostatic latent image on a latent image carrier, developing said latent image with a developer to form a toner image, transferring said toner image on a recording material, and fixing the toner image with a heat roller, is disclosed. The method is characterized by:1) said developer comprises an inorganic fine particle having pH of not lower than 7.0, and2) a resin coating layer containing carbon black is provided on said heat roller, and is grounded.
    Type: Grant
    Filed: June 16, 1989
    Date of Patent: June 25, 1991
    Assignee: Konica Corporation
    Inventors: Hiroya Masaki, Hiroyuki Takagiwa, Meizo Shirose, Michiaki Ishikawa