Patents by Inventor Kohsuke SATOH

Kohsuke SATOH 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).

  • Publication number: 20230279222
    Abstract: Resin particles include a binder resin in each of the resin particles. The binder resin includes a biomass-derived resin, and polyethylene terephthalate or polybutylene terephthalate. An amount A of a biomass-derived component of the biomass-derived resin and an amount B of the polyethylene terephthalate or the polybutylene terephthalate satisfy A>B. Each of the resin particles has a core-shell structure including a shell layer and a core layer. An average thickness of the shell layer is from 100 nm to 500 nm.
    Type: Application
    Filed: March 2, 2023
    Publication date: September 7, 2023
    Applicant: Ricoh Company, Ltd.
    Inventors: Tsuneyasu NAGATOMO, Junichi WATANABE, Yuka MIZOGUCHI, Kohsuke SATOH
  • Publication number: 20230185209
    Abstract: A resin particle contains resin containing a tetrahydrofuran insoluble portion containing a non-linear polymer in which a non-linear prepolymer is cross-linked with a metal ion, wherein the resin particle has a carbon-14 concentration of 5.4 pMC or greater, wherein the tetrahydrofuran insoluble portion has a glass transition temperature of from ?60 to lower than 0 degrees C. as measured by differential scanning calorimetry.
    Type: Application
    Filed: November 29, 2022
    Publication date: June 15, 2023
    Inventors: Kazuoki FUWA, Kohsuke SATOH, Toshihiko SUGIYAMA, Natsuko MATSUSHITA
  • Publication number: 20230185210
    Abstract: A glittering toner includes: a flat metallic pigment having a surface coated with a resin; a polyester-styrene acrylic composite resin; and a polyester resin. When a solubility parameter of the polyester-styrene acrylic composite resin is represented by SP1 (cal/cm3)1/2 and a solubility parameter of the polyester resin is represented by SP2 (cal/cm3)1/2, the SP1 and the SP2 satisfy a relational expression (1): [SP2?SP1>0.3] and the SP1 satisfies a relational expression (2): [10<SP1].
    Type: Application
    Filed: December 12, 2022
    Publication date: June 15, 2023
    Inventors: Tsukiko TAKAHASHI, Kohsuke SATOH, Kazumi SUZUKI, Daichi HISAKUNI, Kazuoki FUWA
  • Publication number: 20230139673
    Abstract: The present disclosure provides a resin particle including a binder resin, in which the binder resin contains a biomass-derived resin and a recycled resin, and a content (% by mass) of the biomass-derived resin and a content (% by mass) of the recycled resin in the binder resin satisfy the following relational equation (1): Content of recycled resin >Content of biomass-derived resin.
    Type: Application
    Filed: October 13, 2022
    Publication date: May 4, 2023
    Applicant: Ricoh Company, Ltd.
    Inventors: Kohsuke SATOH, Tsuneyasu Nagatomo, Junichi Watanabe
  • Patent number: 11079700
    Abstract: An image forming apparatus is provided that includes: an image bearer; a charger; an irradiator; a developing device containing a toner; and a transfer device. The image bearer has a Martens hardness of from 185 to 250 N/m2. The toner satisfies a relation 0.13?X/Dn?0.16, where X [?m] represents an average value of an amount of deformation of the toner by micro-indentation at when a load reaches 3.00×10?4 N at a loading rate of 3.0×10?5 N/sec under an environment of 32 degrees C. and 40% RH, and Dn [?m] represents a number average particle diameter of the toner. The toner contains an external additive comprising silica particles and particles composed mainly of strontium titanate. The particles composed mainly of strontium titanate further contain a third element M selected from the group consisting of La, Mg, Ca, Sn, and Si.
    Type: Grant
    Filed: March 6, 2020
    Date of Patent: August 3, 2021
    Assignee: Ricoh Company, Ltd.
    Inventors: Keiji Makabe, Tsuneyasu Nagatomo, Kohsuke Satoh, Daichi Hisakuni, Kousuke Suzuki, Shintaro Akiyama
  • Patent number: 11061345
    Abstract: A toner including toner particles, each toner particle including a toner base particle, and inorganic particles, wherein the inorganic particles include particles of a fluorine-containing aluminium compound, and a liberation ratio of the inorganic particles is 10% or greater but 60% or less.
    Type: Grant
    Filed: February 24, 2020
    Date of Patent: July 13, 2021
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohsuke Satoh, Tsuneyasu Nagatomo, Keiji Makabe, Daichi Hisakuni
  • Publication number: 20200301308
    Abstract: An image forming apparatus is provided that includes: an image bearer; a charger; an irradiator; a developing device containing a toner; and a transfer device. The image bearer has a Martens hardness of from 185 to 250 N/m2. The toner satisfies a relation 0.13?X/Dn?0.16, where X [?m] represents an average value of an amount of deformation of the toner by micro-indentation at when a load reaches 3.00×10?4 N at a loading rate of 3.0×10?5 N/sec under an environment of 32 degrees C. and 40% RH, and Dn [?m] represents a number average particle diameter of the toner. The toner contains an external additive comprising silica particles and particles composed mainly of strontium titanate. The particles composed mainly of strontium titanate further contain a third element M selected from the group consisting of La, Mg, Ca, Sn, and Si.
    Type: Application
    Filed: March 6, 2020
    Publication date: September 24, 2020
    Inventors: Keiji MAKABE, Tsuneyasu NAGATOMO, Kohsuke SATOH, Daichi HISAKUNI, Kousuke SUZUKI, Shintaro AKIYAMA
  • Publication number: 20200272066
    Abstract: A toner including toner particles, each toner particle including a toner base particle, and inorganic particles, wherein the inorganic particles include particles of a fluorine-containing aluminium compound, and a liberation ratio of the inorganic particles is 10% or greater but 60% or less.
    Type: Application
    Filed: February 24, 2020
    Publication date: August 27, 2020
    Inventors: Kohsuke Satoh, Tsuneyasu Nagatomo, Keiji Makabe, Daichi Hisakuni
  • Patent number: 10295919
    Abstract: A toner is provided. The toner includes toner particles each including a mother particle and external additive particles covering the mother particle. In a SEM image of the toner, toner particles having a ratio Sd/St of from 5% to 50% are present at a frequency of 15% or more, where Sd representing an area of a largest recessed portion D of each toner particle and St representing whole area of the toner particle, Sd and St determined from the SEM image magnified and binarized to discriminate recessed portions and projected portions of the toner particle from each other. An external additive coverage rate Ca at the largest recessed portion D is from 30% to 100%.
    Type: Grant
    Filed: December 19, 2017
    Date of Patent: May 21, 2019
    Assignee: Ricoh Company, Ltd.
    Inventors: Keiji Makabe, Tsuneyasu Nagatomo, Kohsuke Satoh, Kenji Yoneda
  • Publication number: 20180181014
    Abstract: A toner is provided. The toner includes toner particles each including a mother particle and external additive particles covering the mother particle. In a SEM image of the toner, toner particles having a ratio Sd/St of from 5% to 50% are present at a frequency of 15% or more, where Sd representing an area of a largest recessed portion D of each toner particle and St representing whole area of the toner particle, Sd and St determined from the SEM image magnified and binarized to discriminate recessed portions and projected portions of the toner particle from each other. An external additive coverage rate Ca at the largest recessed portion D is from 30% to 100%.
    Type: Application
    Filed: December 19, 2017
    Publication date: June 28, 2018
    Inventors: Keiji MAKABE, Tsuneyasu NAGATOMO, Kohsuke SATOH, Kenji YONEDA
  • Patent number: 9804516
    Abstract: A toner includes a base particle; and an external additive covering the base particle. The toner includes a tetrahydrofuran (THF)-insoluble component having a glass transition temperature determined from a DSC curve when heated for the second time of from ?50° C. to 10° C. and an average circularity not greater than 0.98, and satisfies the following relation: Bt?0.025×Ct?1.80 wherein Bt represents a BET specific surface area [m2/g]; and Ct represents a coverage [%] of the external additive covering the base particle.
    Type: Grant
    Filed: April 21, 2016
    Date of Patent: October 31, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Keiji Makabe, Tsuneyasu Nagatomo, Kohsuke Satoh, Junichi Watanabe, Kenji Yoneda, Daichi Hisakuni
  • Patent number: 9791794
    Abstract: A toner includes a base particle comprising a crystalline polyester resin; and an external additive which is a group of silica particles having a number-average particle diameter of from 0.01 ?m to 0.11 ?m on the surface of the toner. A number ratio of the silica particles having a circularity not less than 0.8 is 20% or more in the total number of the silica particles.
    Type: Grant
    Filed: February 24, 2016
    Date of Patent: October 17, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Junichi Watanabe, Kenji Yoneda, Kohsuke Satoh, Tsuneyasu Nagatomo, Keiji Makabe, Daichi Hisakuni
  • Publication number: 20160334722
    Abstract: A toner includes a base particle; and an external additive covering the base particle. The toner includes a tetrahydrofuran (THF)-insoluble component having a glass transition temperature determined from a DSC curve when heated for the second time of from ?50° C. to 10° C. and an average circularity not greater than 0.98, and satisfies the following relation: Bt?0.025×Ct?1.80 wherein Bt represents a BET specific surface area [m2/g]; and Ct represents a coverage [%] of the external additive covering the base particle.
    Type: Application
    Filed: April 21, 2016
    Publication date: November 17, 2016
    Inventors: Keiji MAKABE, Tsuneyasu Nagatomo, Kohsuke Satoh, Junichi Watanabe, Kenji Yoneda, Daichi Hisakuni
  • Publication number: 20160266507
    Abstract: A toner includes a base particle comprising a crystalline polyester resin; and an external additive which is a group of silica particles having a number-average particle diameter of from 0.01 ?m to 0.11 ?m on the surface of the toner. A number ratio of the silica particles having a circularity not less than 0.8 is 20% or more in the total number of the silica particles.
    Type: Application
    Filed: February 24, 2016
    Publication date: September 15, 2016
    Inventors: Junichi WATANABE, Kenji Yoneda, Kohsuke Satoh, Tsuneyasu Nagatomo, Keiji Makabe, Daichi Hisakuni
  • Patent number: 8703378
    Abstract: A method of manufacturing toner including mixing mother toner particles containing a binder resin and a coloring agent and first particles having an average primary particle diameter of from 100 nm to 1 ?m to using a mixer including a rotary shaft member, multiple stirring members provided to the surface of the shaft member, and a casing to cover the multiple stirring members, wherein the cross section of the inner periphery of the casing relative to a direction perpendicular to the rotation axis of the shaft member is circular around the rotation axis with a substantially constant distance between the inner periphery and the rotation axis. The casing covers the multiple stirring members and a cooling jacket is provided to at least part of the outer periphery of the casing. The weight ratio of the particles to the mother toner particles is from 1.5% to 10%.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: April 22, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohsuke Satoh, Tetsuya Tanaka, Masahiro Kawamoto, Natsuko Matsushita
  • Publication number: 20120070774
    Abstract: A method of manufacturing toner including mixing mother toner particles containing a binder resin and a coloring agent and first particles having an average primary particle diameter of from 100 nm to 1 ?m to using a mixer including a rotary shaft member, multiple stirring members provided to the surface of the shaft member, and a casing to cover the multiple stirring members, wherein the cross section of the inner periphery of the casing relative to a direction perpendicular to the rotation axis of the shaft member is circular around the rotation axis with a substantially constant distance between the inner periphery and the rotation axis. The casing covers the multiple stirring members and a cooling jacket is provided to at least part of the outer periphery of the casing. The weight ratio of the particles to the mother toner particles is from 1.5% to 10%.
    Type: Application
    Filed: September 16, 2011
    Publication date: March 22, 2012
    Inventors: Kohsuke SATOH, Tetsuya Tanaka, Masahiro Kawamoto, Natsuko Matsushita