Patents by Inventor Tomohiko Tokunaga

Tomohiko Tokunaga 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: 9146484
    Abstract: To provide an emulsion polymerized agglomerated toner for electrostatic charge image which is excellent in the fixing property even at a high temperature without deteriorating other properties and which does not emit an odor offensive to people, and a process for its production. An emulsion polymerized agglomerated toner characterized in that the odor index of aliphatic aldehydes measured by gas chromatography is at most 300, and an emulsion polymerized agglomerated toner which is an emulsion polymerized agglomerated toner obtainable via a polymerization step, a flocculation step and an aging step, characterized in that an emulsion polymerized latex before the flocculation step is a latex having a peroxide value of at most 30.
    Type: Grant
    Filed: October 7, 2014
    Date of Patent: September 29, 2015
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Masaya Ota, Tomohiko Tokunaga, Kazuo Mitsuhashi
  • Publication number: 20150024324
    Abstract: To provide an emulsion polymerized agglomerated toner for electrostatic charge image which is excellent in the fixing property even at a high temperature without deteriorating other properties and which does not emit an odor offensive to people, and a process for its production. An emulsion polymerized agglomerated toner characterized in that the odor index of aliphatic aldehydes measured by gas chromatography is at most 300, and an emulsion polymerized agglomerated toner which is an emulsion polymerized agglomerated toner obtainable via a polymerization step, a flocculation step and an aging step, characterized in that an emulsion polymerized latex before the flocculation step is a latex having a peroxide value of at most 30.
    Type: Application
    Filed: October 7, 2014
    Publication date: January 22, 2015
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Masaya OTA, Tomohiko Tokunaga, Kazuo Mitsuhashi
  • Publication number: 20080213683
    Abstract: To provide an emulsion polymerized agglomerated toner for electrostatic charge image which is excellent in the fixing property even at a high temperature without deteriorating other properties and which does not emit an odor offensive to people, and a process for its production. An emulsion polymerized agglomerated toner characterized in that the odor index of aliphatic aldehydes measured by gas chromatography is at most 300, and an emulsion polymerized agglomerated toner which is an emulsion polymerized agglomerated toner obtainable via a polymerization step, a flocculation step and an aging step, characterized in that an emulsion polymerized latex before the flocculation step is a latex having a peroxide value of at most 30.
    Type: Application
    Filed: October 28, 2005
    Publication date: September 4, 2008
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Masaya Ota, Tomohiko Tokunaga, Kazuo Mitsuhashi
  • Patent number: 6720123
    Abstract: A process for producing a toner for developing electrostatic image is described, which involves an agglomerate step wherein a dispersion liquid containing at least primary polymer particles and colorant particles is stirred in a stirring tank to agglomerate the particles to thereby obtain agglomerate of the particles and an aging step wherein the resultant agglomerate of the particles is kept at a temperature higher than the glass transition temperature (Tg) of the primary polymer particles by 10° C. or more for a predetermined period of time to thereby fuse the particles, which process is characterized in that the concentration of solid content (C1) in the agglomerate step is 10 to 40% by weight, and that the concentration of the solid content (C2) in the aging step is in the range of 0.3C1≦C2≦0.8C1.
    Type: Grant
    Filed: February 6, 2002
    Date of Patent: April 13, 2004
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Yuqing Xu, Kazuo Mitsuhashi, Tomohiko Tokunaga, Toyomasa Hoshino
  • Publication number: 20030003387
    Abstract: A process for producing a toner for developing electrostatic image is described, which involves an agglomerate step wherein a dispersion liquid containing at least primary polymer particles and colorant particles is stirred in a stirring tank to agglomerate the particles to thereby obtain agglomerate of the particles and an aging step wherein the resultant agglomerate of the particles is kept at a temperature higher than the glass transition temperature (Tg) of the primary polymer particles by 10° C. or more for a predetermined period of time to thereby fuse the particles, which process is characterized in that the concentration of solid content (C1) in the agglomerate step is 10 to 40% by weight, and that the concentration of the solid content (C2) in the aging step is in the range of 0.3C1 <C2 <0.8C1.
    Type: Application
    Filed: February 6, 2002
    Publication date: January 2, 2003
    Applicant: Mitsubishi Chemical Corporation
    Inventors: Yuqing Xu, Kazuo Mitsuhashi, Tomohiko Tokunaga, Toyomasa Hoshino