Patents by Inventor Masahiro Ikuta

Masahiro Ikuta 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: 9217941
    Abstract: According to one embodiment, a method of manufacturing an erasable toner includes washing toner particles including therein a coloring material that is erasable by heating and a binder resin to obtain a toner cake having the amount of water of 20% by weight to 60% by weight, and drying the toner cake at 40° C. or more and at a temperature which is lower than the complete color erasing temperature of the toner particles by 30° C. or more.
    Type: Grant
    Filed: January 10, 2014
    Date of Patent: December 22, 2015
    Assignee: Toshiba Tec Kabushiki Kaisha
    Inventors: Tsuyoshi Itou, Kazuhisa Takeda, Yasuhito Noda, Takayasu Aoki, Masahiro Ikuta, Takafumi Hara, Motonari Udo
  • Publication number: 20150350477
    Abstract: In accordance with one embodiment, a color erasing apparatus comprises a conveyance path, a color erasing section and a control section. The conveyance path conveys a sheet. The color erasing section erases the color of an image formed with color erasable recording agent serving as recording agent containing coloring agent the color of which can be erased by heating. The control section carries out a control, in a case where the image formed on the sheet is not an image formed with the color erasable recording agent, so that the sheet is not subjected to a color erasing processing by the color erasing section.
    Type: Application
    Filed: May 27, 2014
    Publication date: December 3, 2015
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Kazuhisa Takeda, Tsuyoshi Itou, Masahiro Ikuta, Takafumi Hara, Motonari Udo, Takayasu Aoki, Yasuhito Noda
  • Publication number: 20150268571
    Abstract: Disclosed is a decolorizable electrophotographic toner, including: a binder resin; and a colorant which contains at least a color developable compound and a color developing agent and is covered with an outer shell so as to have a capsule structure, wherein the number ratio of particles having an equivalent circle diameter of 0.6 ?m or more and 2.5 ?m or less of the toner when measured using a flow particle image analyzer after the toner is dispersed in an aqueous medium at a ratio of 0.08% by weight and the resulting dispersion is subjected to a stirring treatment in which stirring is performed at 5000 rpm for 30 minutes using a homogenizer (T-25 digital ULTRA-TURRAX (manufactured by IKA Japan K.K., provided with a shaft generator S25N-10G)) is 30% by number or less.
    Type: Application
    Filed: June 5, 2015
    Publication date: September 24, 2015
    Inventors: Masahiro Ikuta, Takahito Kabai, Takayasu Aoki, Tsuyoshi Itou
  • Patent number: 9128394
    Abstract: An electrophotographic toner produced by mixing a dispersion of colorant particles containing a colorant and a dispersion of release agent particles containing a release agent and having a volume average particle diameter smaller than that of the colorant particles, aggregating the colorant particles and the release agent particles in the dispersion to produce first aggregates, mixing a dispersion of resin particles containing a binder resin and having a volume average particle diameter smaller than that of the release agent particles in the dispersion containing the first aggregates, and aggregating the first aggregates and the resin particles in the dispersion of the first aggregates and the resin particles to coat the first aggregates with the resin particles, producing second aggregates.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: September 8, 2015
    Assignee: Toshiba Tec Kabushiki Kaisha
    Inventors: Takafumi Hara, Masahiro Ikuta, Tsuyoshi Itou, Motonari Udo, Kazuhisa Takeda
  • Publication number: 20150168875
    Abstract: An image forming apparatus includes a first image forming unit configured to form a first image to be transferred to a sheet with a non-decolorizable material, and a second image forming unit configured to form a second image to be transferred to the sheet with a decolorizable material. At least a part of the second image transferred to the sheet is formed on the first image transferred to the sheet.
    Type: Application
    Filed: December 18, 2013
    Publication date: June 18, 2015
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Motonari UDO, Masahiro IKUTA, Kazuhisa TAKEDA, Tsuyoshi ITOU, Takayasu AOKI, Takafumi HARA
  • Patent number: 8940468
    Abstract: Disclosed is a process for production of a decolorable toner, including: aggregating dispersed fine particles of a color material comprising at least a color-forming compound, a color-developing agent and a decoloring agent with dispersed fine particles comprising at least a binder resin comprising a polyester resin to form aggregates in an aqueous medium, adding a reactive polymer having an oxazoline group in to the aqueous medium, and fusing the aggregates in the aqueous medium. As a result, it becomes possible to produce a decolorable toner which suppresses the generation of fine powder due to the release of fine particles of an erasable color material from the toner.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: January 27, 2015
    Assignee: Toshiba Tec Kabushiki Kaisha
    Inventors: Takayasu Aoki, Takafumi Hara, Tsuyoshi Itou, Masahiro Ikuta, Motonari Udo, Koji Shimokusa, Hiroshi Mizuhata
  • Publication number: 20140234768
    Abstract: Provided is a method for producing a toner including: aggregating colorant particles and release agent particles, thereby forming aggregates containing the colorant particles and the release agent particles; aggregating binder resin particles and the obtained aggregates containing the colorant particles and the release agent particles, thereby forming toner particle precursors; and aggregating and fusing the obtained toner particle precursors, thereby forming toner particles, wherein when the average circularity of the toner particles is represented by Rt, Rt satisfies the following formula (1): 0.85?Rt?0.92 (1).
    Type: Application
    Filed: March 13, 2014
    Publication date: August 21, 2014
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Takafumi Hara, Masahiro Ikuta, Tsuyoshi Itou, Motonari Udo, Kazuhisa Takeda
  • Publication number: 20140212805
    Abstract: Provided is a decolorizable toner including a binder resin and colorant particles which contain a color developable compound, a color developing agent, and a decolorizing agent, and have a capsule structure coated with an outer shell, wherein the binder resin is contained in an amount of 60 to 80% by mass with respect to the total amount of the toner components.
    Type: Application
    Filed: March 13, 2014
    Publication date: July 31, 2014
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Takafumi Hara, Masahiro Ikuta, Tsuyoshi Itou, Motonari Udo, Kazuhisa Takeda
  • Patent number: 8790857
    Abstract: Disclosed is a toner obtained by coating surfaces of core particles including at least a binder resin having a carboxyl group and a coloring agent with successive coatings of a water-soluble crosslinking agent capable of crosslinking with a carboxyl group and a water-soluble polymer having a carboxyl group, which have been successively applied on the core particles and crosslinked with each other. The thus-formed toner is provided with a good harmony of favorable fixability represented by a low lowest fixable temperature and favorable storage stability represented by little aggregation after standing at 50° C. for 8 hours.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: July 29, 2014
    Assignee: Toshiba Tec Kabushiki Kaisha
    Inventors: Tsuyoshi Itou, Motonari Udo, Kazuhisa Takeda, Takayasu Aoki, Masahiro Ikuta, Takafumi Hara
  • Patent number: 8785097
    Abstract: Disclosed is a decolorable toner produced by aggregating dispersed fine particles of a color material containing at least a color-forming compound, a color-developing agent and a decoloring agent with dispersed fine particles containing at least a binder resin having a carboxyl group, then adding a compound having a carbodiimide group or an epoxy group reactive with the carboxyl group of the binder resin, and thereafter fusing the aggregate particles, respectively in an aqueous medium. The thus obtained decolorable toner can suppress the generation of fine powder by the release of erasable color material fine particles from the toner particles.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: July 22, 2014
    Assignee: Toshiba Tec Kabushiki Kaisha
    Inventors: Takayasu Aoki, Motonari Udo, Tsuyoshi Itou, Masahiro Ikuta, Takafumi Hara
  • Publication number: 20140199622
    Abstract: According to one embodiment, an erasable toner of the present embodiment includes a binder resin, an electron donating coloring agent, an electron accepting developer, and a discoloring temperature regulating agent, in which when measuring for the first time by differential thermal scanning calorimetry, an endothermic peak temperature Tg of the binder resin and an endothermic peak temperature Th of the discoloring temperature regulating agent satisfy Tg<Th and Th?Tg>25° C.
    Type: Application
    Filed: January 16, 2014
    Publication date: July 17, 2014
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Takayasu AOKI, Takafumi HARA, Masahiro IKUTA, Tsuyoshi ITOU, Motonari UDO, Kazuhisa TAKEDA
  • Publication number: 20140199626
    Abstract: According to one embodiment, a method of manufacturing an erasable toner includes washing toner particles including therein a coloring material that is erasable by heating and a binder resin to obtain a toner cake having the amount of water of 20% by weight to 60% by weight, and drying the toner cake at 40° C. or more and at a temperature which is lower than the complete color erasing temperature of the toner particles by 30° C. or more.
    Type: Application
    Filed: January 10, 2014
    Publication date: July 17, 2014
    Applicant: Toshiba Tec Kabushiki Kaisha
    Inventors: TSUYOSHI ITOU, Kazuhisa Takeda, Yasuhito Noda, Takayasu Aoki, Masahiro Ikuta, Takafumi Hara, Motonari Udo
  • Patent number: 8669036
    Abstract: Disclosed is a producing method of a decolorizable toner, comprising dispersing a mixed composition containing encapsulated colorant particles which are particles containing a color developable compound and a color developing agent and coated with an outer shell, a polymerizable monomer, and a release agent in an aqueous medium, and subjecting the polymerizable monomer to suspension polymerization in the aqueous medium.
    Type: Grant
    Filed: August 31, 2011
    Date of Patent: March 11, 2014
    Assignee: Toshiba Tec Kabushiki Kaisha
    Inventors: Tsuyoshi Itou, Takahito Kabai, Takayasu Aoki, Masahiro Ikuta
  • Publication number: 20140064750
    Abstract: A color-fadable developer contains a binder resin, a color generation compound and a color developing agent. When the developer is heated from a temperature range of 0° C. to 20° C. to a temperature range of 150° C. to 180° C. at a temperature increase rate range of 5° C./min to 10° C./min a first time and a second time, a first differential scanning calorimetry curve based on a measurement by differential scanning calorimetry during the first heating has an endothermic peak that is missing from a second differential scanning calorimetry curve based on a measurement differential scanning calorimetry during the second heating, and has a different peak than the endothermic peak caused by a glass transition point of a binder resin.
    Type: Application
    Filed: July 8, 2013
    Publication date: March 6, 2014
    Inventors: Takafumi HARA, Masahiro IKUTA, Tsuyoshi ITOU, Motonari UDO, Kazuhisa TAKEDA, Takayasu AOKI
  • Patent number: 8603722
    Abstract: There is provided a method for producing a toner that includes encapsulated erasable colored fine particles aggregated with fine particles that contain at least a binder resin and a release agent. The method includes: mixing a dispersion of erasable fine particles with an aggregating agent to form an aggregating agent-containing colored fine particle dispersion; and mixing the aggregating agent-containing colored fine particle dispersion with a fine particle dispersion that contains at least a binder resin and a release agent, so as to aggregate the aggregating agent-containing colored fine particles with the fine particles that contain at least a binder resin and a release agent. In this way, the encapsulated colored fine particles are prevented from being released from the resultant toner particles, and an erasable toner can be obtained that has a narrow particle size distribution and that produces less fogging.
    Type: Grant
    Filed: April 14, 2011
    Date of Patent: December 10, 2013
    Assignee: Toshiba Tec Kabushiki Kaisha
    Inventors: Tsuyoshi Itou, Takayasu Aoki, Koji Imamiya, Masahiro Ikuta
  • Patent number: 8475993
    Abstract: A method for producing a decolorable toner comprising: forming particles containing a color former compound, a color developing agent, and a binder resin; forming first aggregated particles by aggregating and fusing the particles containing the color former compound, the color developing agent, and the binder resin in a dispersion medium; and forming second aggregated particles by aggregating and fusing the first aggregated particles and a binder resin in a dispersion medium.
    Type: Grant
    Filed: November 19, 2010
    Date of Patent: July 2, 2013
    Assignee: Toshiba Tec Kabushiki Kaisha
    Inventor: Masahiro Ikuta
  • Publication number: 20130011776
    Abstract: Disclosed is a decolorable toner produced by aggregating dispersed fine particles of a color material containing at least a color-forming compound, a color-developing agent and a decoloring agent with dispersed fine particles containing at least a binder resin having a carboxyl group, then adding a compound having a carbodiimide group or an epoxy group reactive with the carboxyl group of the binder resin, and thereafter fusing the aggregate particles, respectively in an aqueous medium. The thus obtained decolorable toner can suppress the generation of fine powder by the release of erasable color material fine particles from the toner particles.
    Type: Application
    Filed: June 29, 2012
    Publication date: January 10, 2013
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Takayasu Aoki, Motonari Udo, Tsuyoshi Itou, Masahiro Ikuta, Takafumi Hara
  • Publication number: 20130011775
    Abstract: Disclosed is a toner obtained by coating surfaces of core particles including at least a binder resin having a carboxyl group and a coloring agent with successive coatings of a water-soluble crosslinking agent capable of crosslinking with a carboxyl group and a water-soluble polymer having a carboxyl group, which have been successively applied on the core particles and crosslinked with each other. The thus-formed toner is provided with a good harmony of favorable fixability represented by a low lowest fixable temperature and favorable storage stability represented by little aggregation after standing at 50° C. for 8 hours.
    Type: Application
    Filed: June 29, 2012
    Publication date: January 10, 2013
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Tsuyoshi Itou, Motonari Udo, Kazuhisa Takeda, Takayasu Aoki, Masahiro Ikuta, Takafumi Hara
  • Publication number: 20130011777
    Abstract: Disclosed is a process for production of a decolorable toner, including: aggregating dispersed fine particles of a color material comprising at least a color-forming compound, a color-developing agent and a decoloring agent with dispersed fine particles comprising at least a binder resin comprising a polyester resin to form aggregates in an aqueous medium, adding a reactive polymer having an oxazoline group in to the aqueous medium, and fusing the aggregates in the aqueous medium. As a result, it becomes possible to produce a decolorable toner which suppresses the generation of fine powder due to the release of fine particles of an erasable color material from the toner.
    Type: Application
    Filed: June 29, 2012
    Publication date: January 10, 2013
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Takayasu Aoki, Takafumi Hara, Tsuyoshi Itou, Masahiro Ikuta, Motonari Udo, Koji Shimokusa, Hiroshi Mizuhata
  • Publication number: 20120328977
    Abstract: Encapsulated toner particles are formed by: aggregating core material particles containing at least a colorant and a core material resin in an aqueous dispersion medium to form core particles; adding coating resin particles into the aqueous dispersion medium during progress of the formation of the core material at a point of time when the volume-based median particle diameter of the core particles formed by the aggregation reaches 30 to 83% of that of desired toner particles; and continuing the aggregation to form a coating layer composed of a composite aggregate of the core material particles and the coating resin particles on the core material. In the thus-obtained toner, the colorant is uniformly and well incorporated in the toner particles, and therefore, the coloring ability is improved without causing a problem of release of fine powder.
    Type: Application
    Filed: June 18, 2012
    Publication date: December 27, 2012
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Masahiro Ikuta, Takayasu Aoki, Tsuyoshi Itou, Motonari Udo, Takafumi Hara, Kazuhisa Takeda