Patents by Inventor Mitsuyo Matsumoto

Mitsuyo Matsumoto 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: 12065561
    Abstract: A resin composition is provided that comprises a resin and a phosphorus-based flame retardant. The resin includes a ?-1,3-glucan derivative resin having a main chain having a structure represented by the following structural formula (1): where each of Rs is independently a hydrogen atom or an alkylcarbonyl group, at least one of Rs is an alkylcarbonyl group, and n is a natural number. The phosphorus-based flame retardant has an average particle diameter of 5 ?m or less in the resin.
    Type: Grant
    Filed: June 3, 2021
    Date of Patent: August 20, 2024
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuyo Matsumoto, Yoshitaka Sekiguchi, Natsuki Koike
  • Publication number: 20230331962
    Abstract: A resin composition contains a resin and talc, wherein the resin contains a ?-1,3-glucan derivative resin with the main chain represented by the following Chemical Formula 1, and the talc has an average particle diameter of 10 ?m or less, where R's each independently represent hydrogen atoms or alkyl carbonyl groups, at least one of R's is an alkyl carbonyl group, and n represents a natural number.
    Type: Application
    Filed: April 14, 2023
    Publication date: October 19, 2023
    Inventors: Natsuki KOIKE, Mitsuyo MATSUMOTO
  • Patent number: 11618815
    Abstract: A resin composition is provided. The resin composition comprises an acrylonitrile butadiene styrene resin, a polystyrene resin, a polycarbonate resin, and a phosphorus compound. The amount of the polystyrene resin is equal to or greater than the amount of the acrylonitrile butadiene styrene resin. The amount of the polycarbonate resin is from 70 to 90 parts by mass with respect to 100 parts by mass of all the resins. The phosphorus compound contains a phosphazene compound, and the amount of the phosphazene compound is from 0.1 to 4.0 parts by mass with respect to 100 parts by mass of all the resins.
    Type: Grant
    Filed: June 22, 2020
    Date of Patent: April 4, 2023
    Assignee: RICOH COMPANY, LTD.
    Inventors: Natsuki Koike, Yasushi Akiba, Mitsuyo Matsumoto, Yoshitaka Sekiguchi
  • Publication number: 20220170106
    Abstract: In order to elucidate the mechanism of malignant alteration of pancreatic cancer caused by BACH1, changes in the gene expression depending on the expression level of BACH1 in the pancreatic cancer cell line were clarified by RNA sequencing. As a result of experiments on in vitro migration ability and invasion ability and in vivo orthotopic transplantation, BACH1 was found to be used as an excellent biomarker for epithelial-to-mesenchymal transition of pancreatic cancer when used alone or in combination with its downstream regulator FOXA1.
    Type: Application
    Filed: February 22, 2019
    Publication date: June 2, 2022
    Applicant: TOHOKU UNIVERSITY
    Inventors: Kazuhiko IGARASHI, Mitsuyo MATSUMOTO, Masaki SATO, Hironari NISHIZAWA
  • Publication number: 20210395496
    Abstract: A resin composition is provided that comprises a resin and a phosphorus-based flame retardant. The resin includes a ?-1,3-glucan derivative resin having a main chain having a structure represented by the following structural formula (1): where each of Rs is independently a hydrogen atom or an alkylcarbonyl group, at least one of Rs is an alkylcarbonyl group, and n is a natural number. The phosphorus-based flame retardant has an average particle diameter of 5 ?m or less in the resin.
    Type: Application
    Filed: June 3, 2021
    Publication date: December 23, 2021
    Inventors: Mitsuyo MATSUMOTO, Yoshitaka SEKIGUCHI, Natsuki KOIKE
  • Publication number: 20210009799
    Abstract: A resin composition is provided. The resin composition comprises an acrylonitrile butadiene styrene resin, a polystyrene resin, a polycarbonate resin, and a phosphorus compound. The amount of the polystyrene resin is equal to or greater than the amount of the acrylonitrile butadiene styrene resin. The amount of the polycarbonate resin is from 70 to 90 parts by mass with respect to 100 parts by mass of all the resins. The phosphorus compound contains a phosphazene compound, and the amount of the phosphazene compound is from 0.1 to 4.0 parts by mass with respect to 100 parts by mass of all the resins.
    Type: Application
    Filed: June 22, 2020
    Publication date: January 14, 2021
    Inventors: Natsuki KOIKE, Yasushi AKIBA, Mitsuyo MATSUMOTO, Yoshitaka SEKIGUCHI
  • Patent number: 8691484
    Abstract: Disclosed is a non-magnetic toner for use in developing electrostatic toner image, wherein the toner is produced by a toner production method that includes: dispersing in an aqueous medium an organic dispersion liquid that comprises in an organic solvent a pigment, a binder resin and/or a binder resin precursor, and a releasing agent; removing the organic solvent to prepare a dispersion slurry in which toner particles are dispersed in the aqueous medium; heating the dispersion slurry to a temperature equal to or higher than the melting point of the releasing agent; and washing the toner particles.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: April 8, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Tsuyoshi Nozaki, Chiyoshi Nozaki, Atsushi Yamamoto, Mitsuyo Matsumoto, Takuya Kadota, Katsunori Kurose, Yoshimichi Ishikawa
  • Patent number: 8435709
    Abstract: A toner for developing a latent electrostatic image produced by suspension polymerizing a polymerizable monomer composition in an aqueous dispersion medium, wherein the polymerizable monomer composition contains a polymerizable monomer, a colorant, and a layered inorganic mineral in which at least a part of an interlayer ion is replaced with an organic ion, and a process cartridge and an image forming method using the toner.
    Type: Grant
    Filed: March 17, 2008
    Date of Patent: May 7, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Atsushi Yamamoto, Chiyoshi Nozaki, Tsuyoshi Nozaki, Takuya Kadota, Hiroyuki Murakami, Mitsuyo Matsumoto, Katsunori Kurose, Yoshimichi Ishikawa
  • Patent number: 8309290
    Abstract: A toner including toner particles comprising a binder resin, a coloring agent and a wax. The toner particles are prepared by agglomerating and/or fusing at least two kinds of resin particulates and particles of the coloring agent dispersed in an aqueous medium. A first resin particulate among the at least two kinds of resin particulates contains a resin having a polyester skeleton and the wax. At least 50% by weight of the binder resin is polyester resins.
    Type: Grant
    Filed: September 14, 2007
    Date of Patent: November 13, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Atsushi Yamamoto, Chiyoshi Nozaki, Tsuyoshi Nozaki, Mitsuyo Matsumoto, Takuya Kadota, Hiroyuki Murakami, Katsunori Kurose, Yoshimichi Ishikawa
  • Patent number: 8216755
    Abstract: A toner manufactured by a method including the steps of dissolving or dispersing toner components comprising a binder resin, a colorant, and an encapsulated plasticizer to prepare an oily toner components liquid, and emulsifying or dispersing the oily toner components liquid in an aqueous medium to prepare the toner.
    Type: Grant
    Filed: June 1, 2009
    Date of Patent: July 10, 2012
    Assignee: Ricoh Company, Limited
    Inventors: Yoshimichi Ishikawa, Chiyoshi Nozaki, Tsuyoshi Nozaki, Takuya Kadota, Katsunori Kurose, Mitsuyo Matsumoto, Atsushi Yamamoto
  • Patent number: 8139984
    Abstract: An image forming apparatus, wherein a surface resistivity Rse[?] of a charger and a volume resistivity Rsw [?·cm] of the composition having a low softening point satisfy the following relationship: 0.8×10?1Rse<Rvw<1.5×10Rse is provided. The image forming apparatus contains a photoreceptor; a charger configured to charge the photoreceptor with a charger contacting thereto; an irradiator configured to irradiate the photoreceptor to form an electrostatic latent image thereon; an image developer configured to develop the electrostatic latent image with a toner to form a toner image on the photoreceptor; a transferer configured to transfer the toner image onto a recording material directly or through an intermediate transferer; and a fixer configured to fix the toner image on the recording material, wherein the toner comprises: a binder resin; a colorant; a composition having a low softening point; and an external additive.
    Type: Grant
    Filed: October 26, 2010
    Date of Patent: March 20, 2012
    Assignee: Ricoh Company, Limited
    Inventors: Hiroyuki Murakami, Masahide Inoue, Chiyoshi Nozaki, Tsuyoshi Nozaki, Atsushi Yamamoto, Takuya Kadota, Mitsuyo Matsumoto, Katsunori Kurose, Yoshimichi Ishikawa
  • Patent number: 8110330
    Abstract: To provide a toner that contains at least a binder resin, a colorant, a releasing agent and zeolite, the toner being manufactured through O/W type wet granulation and having an average circularity of 0.970 or greater, and a developer and image forming method using the toner.
    Type: Grant
    Filed: September 18, 2007
    Date of Patent: February 7, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshimichi Ishikawa, Chiyoshi Nozaki, Tsuyoshi Nozaki, Takuya Kadota, Katsunori Kurose, Mitsuyo Matsumoto, Atsushi Yamamoto, Masahide Inoue
  • Patent number: 8039185
    Abstract: To provide a toner for developing a latent electrostatic image comprising at least a colorant, a wax, and a binder resin, wherein Iwax (s) is a value measured by FTIR-ATR Spectroscopy before heating a mirror-surfaced pellet formed by compressing and molding the toner, and Iwax (t) is a value measured by FTIR-ATR Spectroscopy after heating the pellet at a surface temperature thereof of 130° C. for 1 minute satisfy Formulae (1), (2), (3), and (4), Iwax (t)?0.2*100/[T½(° C.)]??Formula (1) Iwax (s)?0.26??Formula (2) Iwax (t)?0.50??Formula (3) Iwax (t)>Iwax (s)??Formula (4) wherein both Iwax(s) and Iwax(t) are obtained by a formula: absorbance derived from the wax (2850 cm?1)/absorbance derived from the binder resin (828 cm?1).
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: October 18, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuyo Matsumoto, Chiyoshi Nozaki, Tsuyoshi Nozaki, Minoru Nakamura, Atsushi Yamamoto
  • Patent number: 8012658
    Abstract: A toner including a binder resin including a polyester resin and a vinyl resin; a wax; and a colorant, wherein the vinyl resin includes a unit obtained from a radically polymerizable monomer having an alkyloxysilyl group. An image forming apparatus including an image bearing member configured to bear an electrostatic image thereon; a developing device configured to develop the electrostatic image with a developer including the toner to form a toner image on the image bearing member; and a transfer device configured to transfer the toner image onto a receiving material. A process cartridge including an image bearing member; and a developing device configured to develop an electrostatic image on the image bearing member with a developer including the toner, wherein the process cartridge is detachably attached to an image forming apparatus as a unit.
    Type: Grant
    Filed: February 5, 2008
    Date of Patent: September 6, 2011
    Assignee: Ricoh Company Limited
    Inventors: Chiyoshi Nozaki, Takuya Kadota, Katsunori Kurose, Mitsuyo Matsumoto, Tsuyoshi Nozaki, Yoshimichi Ishikawa, Atsushi Yamamoto, Hiroyuki Murakami
  • Patent number: 7903998
    Abstract: An image forming apparatus having at least a latent electrostatic image bearing member, and a recharging unit configured to recharge a residual toner remaining on the latent electrostatic image bearing member, wherein after transfer, the residual toner is passed through the recharging unit and is then recovered in a developing device; a charging component of the recharging unit that comes into contact with the latent electrostatic image bearing member is a polymer sheet having a surface roughness (Ra) of 0.12 ?m to 0.51 ?m; the toner contains at least a pigment, a binder resin, and a releasing agent, and contains inorganic fine particles as an external additive, and the amount of the inorganic fine particles and the amount of the releasing agent satisfy three specific Expressions.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: March 8, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuyo Matsumoto, Chiyoshi Nozaki, Takuya Kadota, Katsunori Kurose, Tsuyoshi Nozaki, Atsushi Yamamoto, Yoshimichi Ishikawa
  • Publication number: 20110045401
    Abstract: An image forming apparatus, wherein a surface resistivity Rse[?] of a charger and a volume resistivity Rsw [?·cm] of the composition having a low softening point satisfy the following relationship: 0.8×10?1Rse<Rvw<1.5×10Rse is provided. The image forming apparatus contains a photoreceptor; a charger configured to charge the photoreceptor with a charger contacting thereto; an irradiator configured to irradiate the photoreceptor to form an electrostatic latent image thereon; an image developer configured to develop the electrostatic latent image with a toner to form a toner image on the photoreceptor; a transferer configured to transfer the toner image onto a recording material directly or through an intermediate transferer; and a fixer configured to fix the toner image on the recording material, wherein the toner comprises: a binder resin; a colorant; a composition having a low softening point; and an external additive.
    Type: Application
    Filed: October 26, 2010
    Publication date: February 24, 2011
    Inventors: Hiroyuki MURAKAMI, Masahide Inoue, Chiyoshi Nozaki, Tsuyoshi Nozaki, Atsushi Yamamoto, Takuya Kadota, Mitsuyo Matsumoto, Katsunori Kurose, Yoshimichi Ishikawa
  • Patent number: 7867685
    Abstract: An image forming method, including charging a photoreceptor with a charger contacting thereto; irradiating the photoreceptor to form an electrostatic latent image thereon; developing the electrostatic latent image with a toner to form a toner image on the photoreceptor; transferring the toner image onto a recording material directly or through an intermediate transferer; and fixing the toner image on the recording material, wherein the toner includes a binder resin; a colorant; a composition having a low softening point; and an external additive, and wherein a surface resistivity Rse [?] of the charger and a volume resistivity Rsw [?·cm] of the composition having a low softening point satisfy the following relationship: 0.8×10?1Rse<Rvw<1.5×10Rse.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: January 11, 2011
    Assignee: Ricoh Company, Limited
    Inventors: Hiroyuki Murakami, Masahide Inoue, Chiyoshi Nozaki, Tsuyoshi Nozaki, Atsushi Yamamoto, Takuya Kadota, Mitsuyo Matsumoto, Katsunori Kurose, Yoshimichi Ishikawa
  • Patent number: 7829254
    Abstract: The present invention aims at providing non-magnetic toner which is excellent in fixing property and charge property and capable of inhibiting occurrence of scumming, as well as an image forming apparatus and a process cartridge using the non-magnetic toner. A non-magnetic toner comprising: a toner base particle which comprises a binding resin, and a colorant; and external additives, wherein a surface of the toner base particle contains at least a resin having at least silanol group, and the external additives contain at least particles composed of silicon oxide.
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: November 9, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Katsunori Kurose, Chiyoshi Nozaki, Tsuyoshi Nozaki, Atsushi Yamamoto, Mitsuyo Matsumoto
  • Publication number: 20100227265
    Abstract: A colorless transparent toner including a binder resin and a layered inorganic mineral, wherein the layered inorganic mineral is an organic modified layered inorganic mineral, in which at least part of ions present between layers are modified with an organic ion.
    Type: Application
    Filed: March 4, 2010
    Publication date: September 9, 2010
    Inventors: Mitsuyo MATSUMOTO, Chiyoshi Nozaki, Atsushi Yamamoto
  • Patent number: 7709171
    Abstract: The present invention provides a charge control agent, adapted to control charging ability of resins or compositions containing resins, comprising a copolymer that comprises a polymer block A and a polymer block B, the polymer block A is prepared by copolymerizing a maleimide, which being unsubstituted or substituted for a hydrogen atom of an imide group by an electron-donating group, and styrene or a styrene derivative, and the polymer block B is formed of a polymer of styrene or a styrene derivative.
    Type: Grant
    Filed: July 18, 2007
    Date of Patent: May 4, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Atsushi Yamamoto, Chiyoshi Nozaki, Tsuyoshi Nozaki, Mitsuyo Matsumoto, Katsunori Kurose