Patents by Inventor Toshihiko Yamato

Toshihiko Yamato 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: 7906263
    Abstract: The color toner for developing electrostatic latent images comprising a colored resin particle containing at least a binder resin, a colorant, a charge control agent and a parting agent, wherein an extracted liquid with water by means of a hot water extraction method from said colorant has a pH value in the range from 6.0 to 8.0, said colored resin particle has a volume average particle diameter (Dv) in the range from 4 to 10 ?m and an average circularity in the range from 0.93 to 0.995, an amount of extracted components with methanol is 7% by weight or less, and an amount of residual volatile compounds is 500 ppm or less. The color toner for developing electrostatic latent images has excellent image-reproducibility and environmental durability and can form an image with a stable image density under a high temperature and high humidity condition.
    Type: Grant
    Filed: March 14, 2005
    Date of Patent: March 15, 2011
    Assignee: Zeon Corporation
    Inventors: Hiroshi Nakatani, Toshihiko Yamato, Hiroto Kidokoro
  • Publication number: 20080044752
    Abstract: The color toner for developing electrostatic latent images comprising a colored resin particle containing at least a binder resin, a colorant, a charge control agent and a parting agent, wherein an extracted liquid with water by means of a hot water extraction method from said colorant has a pH value in the range from 6.0 to 8.0, said colored resin particle has a volume average particle diameter (Dv) in the range from 4 to 10 ?m and an average circularity in the range from 0.93 to 0.995, an amount of extracted components with methanol is 7% by weight or less, and an amount of residual volatile compounds is 500 ppm or less. The color toner for developing electrostatic latent images has excellent image-reproducibility and environmental durability and can form an image with a stable image density under a high temperature and high humidity condition.
    Type: Application
    Filed: March 14, 2005
    Publication date: February 21, 2008
    Applicant: ZEON CORPORATION
    Inventors: Hiroshi Nakatani, Toshihiko Yamato, Hiroto Kidokoro
  • Patent number: 7078144
    Abstract: The present invention relates to a method for manufacturing a toner with adjusted particle size distribution having a step of preparing colored particles that contain a binder resin and a colorant, and a step of classifying the colored particles. In the classification step, a classifier that has a plurality of vane-wheel classifying rotors coaxially in a casing, enables the rotating speed of each classifying rotor to be set to be the same as or different from each other, and can simultaneously perform a plurality of stages of classification corresponding to each classifying rotor is used; and the powder material comprising colored particles to which a fluidizing agent is added is fed to the classifier to perform classification.
    Type: Grant
    Filed: December 17, 2003
    Date of Patent: July 18, 2006
    Assignee: Zeon Corporation
    Inventors: Nobuyasu Ota, Toshihiko Yamato
  • Publication number: 20040253531
    Abstract: The present invention relates to a method for manufacturing a toner with adjusted particle size distribution having a step of preparing colored particles that contain a binder resin and a colorant, and a step of classifying the colored particles. In the classification step, a classifier that has a plurality of vane-wheel classifying rotors coaxially in a casing, enables the rotating speed of each classifying rotor to be set to be the same as or different from each other, and can simultaneously perform a plurality of stages of classification corresponding to each classifying rotor is used; and the powder material comprising colored particles to which a fluidizing agent is added is fed to the classifier to perform classification.
    Type: Application
    Filed: December 17, 2003
    Publication date: December 16, 2004
    Applicant: ZEON CORPORATION
    Inventors: Nobuyasu Ota, Toshihiko Yamato