Patents by Inventor Katsutoshi Wakamiya

Katsutoshi Wakamiya 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: 4888264
    Abstract: A mixture of a colorant, and a binder compound having an aliphatic hydrocarbon long chain and having a relatively low melt viscosity, is kneaded in a molten state in the presence of solid media such as balls or beads to form a uniform mixture in which the colorant particles or aggregates have been disintegrated to a size of 5 .mu. or below. Solid particles which may be used as a toner are formed from the uniform mixture and may be encapsulated, as desired, to provide a capsule toner.
    Type: Grant
    Filed: June 6, 1988
    Date of Patent: December 19, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toru Matsumoto, Toshiyuki Koshio, Yasuhide Goseki, Hisayuki Ushiyama, Masuo Yamazaki, Ichiro Ohsaki, Toshiaki Nakahara, Junichi Kurimoto, Katsutoshi Wakamiya
  • Patent number: 4740443
    Abstract: An encapsulated toner for development of electrical latent images comprises a core particle containing a colorant and a soft solid material, inorganic fine particles attached to the vicinity of the surface of the core particle, and a shell coating the core particle and the inorganic fine particles. The inorganic fine particles function to, e.g., reinforce the encapsulated toner with a thin shell and may be attached to the core particles through dry-mixing. The core particles with the attached inorganic particles may be coated with a shell resin through phase separation.
    Type: Grant
    Filed: August 20, 1987
    Date of Patent: April 26, 1988
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiaki Nakahara, Junichi Kurimoto, Yasuhide Goseki, Toshiyuki Koshio, Hisayuki Ochi, Hisayuki Ushiyama, Toru Matsumoto, Ichiro Ohsaki, Katsutoshi Wakamiya, Masuo Yamazaki
  • Patent number: 4661430
    Abstract: A developing method, which comprises arranging a latent image-bearing member which bears a latent image on the surface and a toner-carrying member which carries an insulating non-magnetic toner at the developing section with a certain gap provided therebetween, coating the toner-carrying member with the insulating non-magnetic toner, conveying the resultant coated layer to the developing section while regulating the thickness thinner than said gap and developing the latent image on the latent image-bearing member under the application of an alternate electric field on the toner. Since the toner has a form of a microcapsule comprising a soft core material and a hard shell material and also contains a colorant in addition to the core material, adequate discharging can be effected during triboelectric charging to give an image with a constant density through stably charged state.
    Type: Grant
    Filed: August 6, 1984
    Date of Patent: April 28, 1987
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsutoshi Wakamiya, Toru Matsumoto, Masuo Yamazaki
  • Patent number: 4656111
    Abstract: A pressure-fixable toner comprising a combination of a compound A having a hydrocarbon chain and a compound B having an amino group in addition to a hydrocarbon chain is excellent in dispersibility of colorant, pressure fixing characteristic and developing characteristic. Further, an encapsulated pressure-fixable toner comprising a core of the pressure-fixable toner particles and a shell encapsulating the core is also excellent in these properties.
    Type: Grant
    Filed: January 22, 1985
    Date of Patent: April 7, 1987
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsutoshi Wakamiya, Toru Matsumoto, Masuo Yamazaki
  • Patent number: 4626490
    Abstract: A core material comprising a binder mixture of a long chain organic compound and an ester of a higher alcohol and a higher carboxylic acid is encapsulated with a thin shell material to give an encapsulated toner. The encapsulated toner has a uniform structure and a narrow particle size distribution and is excellent in developing and fixation characteristics, when used in electrophotography, etc.
    Type: Grant
    Filed: January 22, 1985
    Date of Patent: December 2, 1986
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masuo Yamazaki, Katsutoshi Wakamiya, Toru Matsumoto, Ichiro Ohsaki, Toshiaki Nakahara, Hisayuki Ushiyama
  • Patent number: 4610944
    Abstract: A process for producing a toner, comprising the steps of suspending a molten mixture of starting materials of a binder containing a compound having a hydrocarbon chain and a colorant in an aqueous dispersing medium in the presence of a hardly water-soluble fine powdery inorganic dispersant, cooling the dispersed particles, and recovering the cooled particles.
    Type: Grant
    Filed: January 3, 1984
    Date of Patent: September 9, 1986
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toru Matsumoto, Masuo Yamazaki, Katsutoshi Wakamiya
  • Patent number: 4590142
    Abstract: A capsule toner, comprising core particles of a core material exhibiting a cloud point within the range of from 30 to 90 and a penetration within the range of from 2 to 15, and a shell material coating the core particles. The capsule toner is preferably formed by dispersing the core particles in solution of the shell material in a good solvent for the shell material, and then adding a poor solvent for the shell material to cause the deposition of the shell material on the core particles.
    Type: Grant
    Filed: August 29, 1984
    Date of Patent: May 20, 1986
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masuo Yamazaki, Toru Matsumoto, Katsutoshi Wakamiya, Ichiro Ohsaki, Toshiaki Nakahara, Hisayuki Ushiyama
  • Patent number: 4581312
    Abstract: A pressure-fixable capsule toner for electrophotography having characteristics such as good combination of fixability and durability and also a stable charge controlling characteristic is provided. The core materials typically are of polyethylene or paraffin wax. The shell material is a vinyl polymer characterized by low molecular weight distribution represented by a ratio of weight-average molecular weight/number average molecular weight of not larger than 3.5. The vinyl polymer is preferably a copolymer of styrene or a derivative thereof and a tertiary amino-group containing vinyl monomer.
    Type: Grant
    Filed: August 28, 1984
    Date of Patent: April 8, 1986
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiaki Nakahara, Ichiro Ohsaki, Masuo Yamazaki, Katsutoshi Wakamiya, Toru Matsumoto, Hisayuki Ushiyama
  • Patent number: 4514485
    Abstract: An electrophotographic developer comprises magnetic particles coated with a low surface energy resin, toner particles and electroconductive fine powders. This developer can develop solid areas uniformly and does not form fog.
    Type: Grant
    Filed: August 19, 1982
    Date of Patent: April 30, 1985
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hisayuki Ushiyama, Hisayuki Ochi, Tatsuo Miyamae, Katsutoshi Wakamiya