Patents by Inventor Katsuru Matsumoto

Katsuru 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: 8877416
    Abstract: A toner includes a binder resin, a colorant, and a benzilic acid compound. The binder resin contains a polyester resin A obtained by subjecting aromatic dicarboxylic acid, rosin and trivalent or higher-valent alcohol as starting materials to polycondensation, a content of the rosin in a sum of the starting materials being 60% by weight or more, and a polyester resin B obtained by subjecting aromatic dicarboxylic acid and polyhydric alcohol as starting materials to polycondensation.
    Type: Grant
    Filed: June 9, 2011
    Date of Patent: November 4, 2014
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Satoru Ariyoshi, Yasuhiro Shibai, Katsuru Matsumoto, Nobuhiro Maezawa
  • Patent number: 8580473
    Abstract: A toner includes a binder resin and a colorant. The binder resin contains a polyester resin A obtained by subjecting aromatic dicarboxylic acid, rosin, and trivalent or higher-valent alcohol as starting materials to polycondensation, a content of the rosin in a sum of the starting materials being 60% by weight or more, and a polyester resin B obtained by subjecting aromatic dicarboxylic acid and polyhydric alcohol as starting materials to polycondensation, the polyester resin B having a viscosity of 103 Pa·s or more and 105 Pa·s or less at a softening temperature of the polyester resin A, the polyester resin B being contained in an amount of 50 parts by weight or more and 200 parts by weight or less relative to 100 parts by weight of the polyester resin A.
    Type: Grant
    Filed: June 9, 2011
    Date of Patent: November 12, 2013
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Satoru Ariyoshi, Yasuhiro Shibai, Nobuhiro Maezawa, Katsuru Matsumoto
  • Patent number: 8273515
    Abstract: A toner containing a lignin resin, a carbon-neutral biomass polymer having a low environmental load and taking global environmental protection into account, as a constitutional component of a binder resin, and having a wide fixing non-offset range and an excellent fixing property, is provided. The toner contains at least a binder resin, a colorant, and a release agent. Furthermore, in the toner, the binder resin includes a resin A that is a lignin resin and a resin B that is another resin component, and the resin B has a peak top molecular weight of 103 to 104 and an acid number of 20 or less.
    Type: Grant
    Filed: November 18, 2009
    Date of Patent: September 25, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Satoru Ariyoshi, Katsuru Matsumoto
  • Patent number: 8252501
    Abstract: There is provided a method of manufacturing coalesced resin particles for obtaining coalesced resin particles by coalescing aggregated resin particles in a grain boundary-free state in a short period of time while keeping a grain size distribution within a narrow range. In a coalescence process, a slurry of aggregated resin particles is flowed through an inside of a pipe under predetermined heating and pressurizing conditions. In a before-cooling decompression process, a slurry of coalesced resin particles flowing through the inside of the pipe in a heat and pressure-applied state is subjected to pressure reduction before it is cooled down to a predetermined temperature in a cooling process. Then, in a decompression process, a coalesced resin particle slurry that has been cooled in the cooling process while being flowed through the inside of the pipe is decompressed to an atmospheric pressure.
    Type: Grant
    Filed: July 24, 2009
    Date of Patent: August 28, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Nobuhiro Maezawa, Katsuru Matsumoto
  • Patent number: 8187783
    Abstract: A method of manufacturing a toner in which uneven distribution of toner ingredients by subjecting them to fine dispersion is prevented and which is excellent in transferability, cleaning properties, anti-filming properties, anti-blocking properties, high-temperature offset resisting properties and transparency is provided. Melt-kneaded substances include binder resins, colorants and release agents, respectively. The colorant and the release agent are dispersed in the binder resin. The melt-kneaded substance is negatively charged by an anionic dispersant, whereas the melt-kneaded substance is positively charged by a cationic dispersant. An aggregate is formed by heteroaggregation of the melt-kneaded substances. The aggregate is fused by heating and formed into a spherical toner.
    Type: Grant
    Filed: July 2, 2008
    Date of Patent: May 29, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keiichi Kikawa, Yasuhiro Shibai, Katsuru Matsumoto
  • Patent number: 8163458
    Abstract: A toner capable of forming high quality images of excellent image reproducibility at high definition and high resolution, being decreased for the bleed-out of a wax ingredient to the surface, causing less filming to a photoreceptor and offset phenomenon in a high temperature region, is provided. The toner is manufactured by a method including a preliminary pulverizing step of pulverizing a melt-kneaded product of toner raw materials in a liquid to obtain a coarse powder slurry containing a coarse toner powder, a finely pulverizing step of passing the coarse powder slurry through a pressure resistant nozzle under heating and pressurization thereby further pulverizing the coarse toner powder to obtain a fine powder slurry containing a fine toner powder and in a heated and pressurized state, a cooling step of cooling the fine powder slurry, and a depressurizing step of depressurizing the fine powder slurry.
    Type: Grant
    Filed: July 3, 2008
    Date of Patent: April 24, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keiichi Kikawa, Katsuru Matsumoto
  • Patent number: 8097395
    Abstract: A method of manufacturing toner particles capable of decreasing the manufacturing costs by simplifying the manufacturing apparatus and by decreasing the number of the steps, as well as to provide toner particles, a two-component developer, a developing apparatus and an image forming apparatus are provided. A high-pressure homogenizer is constituted by a tank, a feed pump, a high-pressure pump, a heat exchanger, a nozzle, a first depressurizing module, a cooling unit, a second depressurizing module and a take-out port arranged in this order. A flow path constituted in the first depressurizing module has a straight portion tilted with respect to a direction in which the aqueous slurry passes and a portion for relaxing the flow of the aqueous slurry.
    Type: Grant
    Filed: November 30, 2010
    Date of Patent: January 17, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Katsuru Matsumoto, Keiichi Kikawa, Nobuhiro Maezawa
  • Patent number: 8092968
    Abstract: The toner includes a plurality of toner particles containing a binder resin and a colorant. In toner particles, according to measurement by a flow particle image analyzer, the content of small size particles having a circle-equivalent diameter of 0.5 to 2.0 ?m is 5% by number or less based on the entire toner particles, the content of medium size particles having a circle-equivalent diameter of more than 2.0 ?m and 4.0 ?m or less is 20% by number or more and 30% by number or less based on the entire toner particles, and the content of large size particles having a circle-equivalent diameter of more than 4.0 ?m and 6.0 ?m or less is 50% by number or more and 70% by number or less based on the entire toner particles, and the shape factor of the toner particles SF1 is 130 or more and 140 or less.
    Type: Grant
    Filed: March 13, 2009
    Date of Patent: January 10, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keiichi Kikawa, Ayae Nagaoka, Katsuru Matsumoto
  • Publication number: 20110305988
    Abstract: A toner includes a binder resin and a colorant. The binder resin contains a polyester resin A obtained by subjecting aromatic dicarboxylic acid, rosin, and trivalent or higher-valent alcohol as starting materials to polycondensation, a content of the rosin in a sum of the starting materials being 60% by weight or more, and a polyester resin B obtained by subjecting aromatic dicarboxylic acid and polyhydric alcohol as starting materials to polycondensation, the polyester resin B having a viscosity of 103 Pa·s or more and 105 Pa·s or less at a softening temperature of the polyester resin A, the polyester resin B being contained in an amount of 50 parts by weight or more and 200 parts by weight or less relative to 100 parts by weight of the polyester resin A.
    Type: Application
    Filed: June 9, 2011
    Publication date: December 15, 2011
    Inventors: Satoru ARIYOSHI, Yasuhiro Shibai, Nobuhiro Maezawa, Katsuru Matsumoto
  • Publication number: 20110305985
    Abstract: A toner includes a binder resin, a colorant, and, a benzilic acid compound. The binder resin contains a polyester resin A obtained by subjecting aromatic dicarboxylic acid, rosin and trivalent or higher-valent alcohol as starting materials to polycondensation, a content of the rosin in a sum of the starting materials being 60% by weight or more, and a polyester resin B obtained by subjecting aromatic dicarboxylic acid and polyhydric alcohol as starting materials to polycondensation.
    Type: Application
    Filed: June 9, 2011
    Publication date: December 15, 2011
    Inventors: Satoru ARIYOSHI, Yasuhiro Shibai, Katsuru Matsumoto, Nobuhiro Maezawa
  • Publication number: 20110305982
    Abstract: A toner includes a binder resin containing a polyester resin A obtained by subjecting aromatic dicarboxylic acid, rosin, and trivalent or higher-valent alcohol as starting materials to polycondensation, a content of the rosin in a sum of the starting materials being 60% by weight or more, and a polyester resin B obtained by subjecting aromatic dicarboxylic acid and polyalcohol as starting materials to polycondensation; a dispersing aid for dispersing the polyester resin A into the polyester resin B; and a colorant.
    Type: Application
    Filed: June 9, 2011
    Publication date: December 15, 2011
    Inventors: Katsuru MATSUMOTO, Yasuhiro SHIBAI, Satoru ARIYOSHI, Nobuhiro MAEZAWA
  • Patent number: 8067143
    Abstract: A functional particle is manufactured by a method including an aggregating step, a depressurizing step, and a cooling step. In the aggregating step, the functional particle is obtained by flowing a mixed slurry containing a core particle and a shell particle through a coiled pipeline while heating the mixed slurry to a glass transition temperature or higher of the core particle, to deposit the shell particles on the surface of the core particle. In the depressurizing step, the grain size of the functional particle is controlled and the coarse particle is pulverized to make the grain size of the functional particles uniform. In the cooling step, re-aggregation of the functional particles with unified grain size is prevented.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: November 29, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keiichi Kikawa, Katsuru Matsumoto, Nobuhiro Maezawa
  • Patent number: 8021817
    Abstract: A toner in form of aggregate of resin-containing particles is manufactured by aggregating the resin-containing particles which contain binder resin and the colorant, with the aid of an aggregate dispersant containing a polymer in which anionic polar groups are bonded to a main chain. To be specific, salt of divalent or higher valent metal is added to a slurry of the resin-containing particles so that a metal ion and the anionic polar group are bonded to each other, and a temperature of the slurry is increased so that a bond between the anionic polar group and a water molecule is broken. This decreases water-solubility of the polymer so that the resin-containing particles are aggregated.
    Type: Grant
    Filed: August 1, 2007
    Date of Patent: September 20, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keiichi Kikawa, Katsuru Matsumoto, Yasuhiro Shibai
  • Publication number: 20110069992
    Abstract: A method of manufacturing toner particles capable of decreasing the manufacturing costs by simplifying the manufacturing apparatus and by decreasing the number of the steps, as well as to provide toner particles, a two-component developer, a developing apparatus and an image forming apparatus are provided. A high-pressure homogenizer is constituted by a tank, a feed pump, a high-pressure pump, a heat exchanger, a nozzle, a first depressurizing module, a cooling unit, a second depressurizing module and a take-out port arranged in this order. A flow path constituted in the first depressurizing module has a straight portion tilted with respect to a direction in which the aqueous slurry passes and a portion for relaxing the flow of the aqueous slurry.
    Type: Application
    Filed: November 30, 2010
    Publication date: March 24, 2011
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Katsuru Matsumoto, Keiichi Kikawa, Nobuhiro Maezawa
  • Patent number: 7910279
    Abstract: A method of manufacturing aggregate particles capable of obtaining aggregate particles having high mechanical strength, small particle size, with narrow particle size distribution width by preventing interfusion of bubbles in the aggregate particles during stirring is provided. Aggregate particles are manufactured by stirring a resin particle slurry including resin particles dispersed in an aqueous medium and contained in a stirring vessel by a stirring section having a impeller and two or more screen members disposed so as to surround the impeller in the stirring vessel and each formed with a plurality of slits and aggregating the resin particles.
    Type: Grant
    Filed: November 8, 2007
    Date of Patent: March 22, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Nobuhiro Maezawa, Katsuru Matsumoto, Keiichi Kikawa
  • Patent number: 7887986
    Abstract: A method of manufacturing toner particles capable of decreasing the manufacturing costs by simplifying the manufacturing apparatus and by decreasing the number of the steps, as well as to provide toner particles, a two-component developer, a developing apparatus and an image forming apparatus are provided. A high-pressure homogenizer is constituted by a tank, a feed pump, a high-pressure pump, a heat exchanger, a nozzle, a first depressurizing module, a cooling unit, a second depressurizing module and a take-out port arranged in this order. A flow path constituted in the first depressurizing module has a straight portion tilted with respect to a direction in which the aqueous slurry passes and a portion for relaxing the flow of the aqueous slurry.
    Type: Grant
    Filed: August 8, 2008
    Date of Patent: February 15, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Katsuru Matsumoto, Keiichi Kikawa, Nobuhiro Maezawa
  • Patent number: 7875413
    Abstract: There is provided a capsulated toner which has low-temperature fixing ability, good storage stability, excellent charge stability, high fixing strength to a sheet paper, and low consumption, and is capable of forming a color image of high-definition, high-gloss, and high-density. The capsulated toner for electrophotography includes a shell layer containing a cycloolefin copolymer resin and a core particle including a synthetic resin different from the cycloolefin copolymer resin, wherein the capsulated toner has a core/shell type structure.
    Type: Grant
    Filed: May 1, 2007
    Date of Patent: January 25, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yasuhiro Shibai, Katsuru Matsumoto
  • Patent number: 7833446
    Abstract: The aggregated particles are manufactured through a method of manufacturing aggregated particles, which includes an aggregating step, a depressurizing step, and a cooling step. In the aggregating step, a slurry is prepared which contains aggregated particles obtained by flowing an aqueous slurry of resin fine particles having a volume average particle diameter in the range of 0.4 ?m to 3 ?m through a coiled piping in a heated and pressurized state and thereby aggregating the resin fine particles. In the depressurizing step, the slurry containing the aggregated particles is depressurized, and a particle size control is conducted by disintegrating coarse particles so as to homogenize particle diameters of the aggregated particles. In the cooling step, the slurry containing the aggregated particles of which particle diameters have been homogenized is cooled.
    Type: Grant
    Filed: August 1, 2007
    Date of Patent: November 16, 2010
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Nobuhiro Maezawa, Katsuru Matsumoto, Keiichi Kikawa
  • Patent number: 7781139
    Abstract: A toner manufacturing method that allows production of toner having desired characteristics with stability in accordance with fusion emulsification technique for obtaining a toner by granulating a resin kneaded product while dispersing it in an aqueous medium. A resin kneaded product containing at least a binder resin and a colorant is mixed with a dispersant/water-containing aqueous medium. The resultant admixture is stirred by an stirring apparatus including a screen with an admixture discharge hole disposed internally of a vessel and a rotor disposed in an stirring space created by the screen.
    Type: Grant
    Filed: December 4, 2006
    Date of Patent: August 24, 2010
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Satoru Ariyoshi, Yoshitaka Kawase, Keiichi Kikawa, Katsuru Matsumoto
  • Patent number: 7770828
    Abstract: Method of manufacturing resin particles capable of manufacturing resin particles of controlled particle size stably and efficiently by removing bubbles from the surface of a molten kneaded product as the raw material for resin particles thereby sufficiently ensuring action sites for a surfactant on the surface of the molten kneaded product, is provided. The method includes a coarsely-pulverizing step of pressurizing a mixture of a molten kneaded product containing a synthetic resin and an aqueous medium containing a surfactant to 15 MPa to 120 MPa thereby removing bubbles attached to the molten kneaded product containing the synthetic resin, and a finely-granulating step of finely granulating, by a high pressure homogenizer method, an aqueous slurry containing coarse particles of a molten kneaded product passing through a pressure proof nozzle in the coarsely-pulverizing step and in a state where bubbles attached to the surface are removed.
    Type: Grant
    Filed: November 9, 2007
    Date of Patent: August 10, 2010
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Katsuru Matsumoto, Keiichi Kikawa, Ayae Nagaoka