Patents by Inventor Toru Takatsuna

Toru Takatsuna 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: 20210041798
    Abstract: A magnetic toner includes toner particles. The toner particles each include a toner mother particle and an external additive attached to a surface of the toner mother particle. The toner mother particles contain a binder resin and a magnetic powder. The external additive includes resin particles as external additive particles. The resin particles have a blocking rate of no greater than 40% by mass. The resin particles have a number average primary particle diameter of at least 40 nm and no greater than 120 nm. A resin constituting the resin particles is a vinyl resin including repeating units represented by general formulas (1) and (2), and a repeating unit derived from a sulfo group-containing vinyl compound. The content of the repeating unit derived from the sulfo group-containing vinyl compound in the vinyl resin is at least 0.1 mol % and no greater than 3.
    Type: Application
    Filed: August 4, 2020
    Publication date: February 11, 2021
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Toru TAKATSUNA, Sho SUMIOKA
  • Publication number: 20200285161
    Abstract: A toner includes toner particles each including a toner mother particle. The toner mother particles contain a binder resin, a magnetic powder, and conductive titanium oxide particles. The conductive titanium oxide particles have an aspect ratio of at least 5.0. The amount of the conductive titanium oxide particles is at least 2 parts by mass and no greater than 10 parts by mass relative to 100 parts by mass of the binder resin.
    Type: Application
    Filed: March 3, 2020
    Publication date: September 10, 2020
    Applicant: KYOCERA Document Solutions Inc.
    Inventor: Toru TAKATSUNA
  • Patent number: 9829817
    Abstract: A developer includes a toner including toner particles and a carrier including carrier particles. The carrier particles each include a carrier core and a carrier coating layer covering the carrier core. The carrier coating layer contains a fluorine-containing resin. The toner particles each include a toner mother particle and resin particles located on a surface of the toner mother particle. The resin particles have a number average primary particle diameter of at least 70 nm and no greater than 200 nm. A dispersion obtained by dispersing 0.1 g of the resin particles in 100 mL of distilled water has an electrical conductivity of at least 2.5 ?S/m and no greater than 6.0 ?S/m. A degree of aggregation Y160 of the resin particles represented by expression (1) “Y160=100×M160A/M160B” is at least 15% by mass and no greater than 40% by mass.
    Type: Grant
    Filed: March 7, 2017
    Date of Patent: November 28, 2017
    Assignee: KYOCERA Document Solutions Inc.
    Inventor: Toru Takatsuna
  • Publication number: 20170261875
    Abstract: A developer includes a toner including toner particles and a carrier including carrier particles. The carrier particles each include a carrier core and a carrier coating layer covering the carrier core. The carrier coating layer contains a fluorine-containing resin. The toner particles each include a toner mother particle and resin particles located on a surface of the toner mother particle. The resin particles have a number average primary particle diameter of at least 70 nm and no greater than 200 nm. A dispersion obtained by dispersing 0.1 g of the resin particles in 100 mL of distilled water has an electrical conductivity of at least 2.5 ?S/m and no greater than 6.0 ?S/m. A degree of aggregation Y160 of the resin particles represented by expression (1) “Y160=100×M160A/M160B” is at least 15% by mass and no greater than 40% by mass.
    Type: Application
    Filed: March 7, 2017
    Publication date: September 14, 2017
    Applicant: KYOCERA Document Solutions Inc.
    Inventor: Toru TAKATSUNA
  • Patent number: 9423713
    Abstract: A positively chargeable electrostatic latent image developing toner includes a plurality of toner particles each including a toner mother particle and an external additive adhering to a surface of the toner mother particle. The external additive includes metal oxide particles and coat layers that are each disposed over a surface of a corresponding one of the metal oxide particles. The coat layers contain a nitrogen-containing resin. The metal oxide particles contain metal ions having an electronegativity of no greater than 11.
    Type: Grant
    Filed: April 7, 2015
    Date of Patent: August 23, 2016
    Assignee: KYOCERA Document Solutions Inc.
    Inventor: Toru Takatsuna
  • Patent number: 9304426
    Abstract: The present disclosure relates to an electrostatic latent image developing toner containing a toner particle including a toner core containing a binder resin and a shell layer coating a surface of the toner core. The shell layer contains a unit derived from a monomer of a thermosetting resin, and a unit derived from a thermoplastic resin. The thermosetting resin is one or more resins selected from the group of amino resins consisting of a melamine resin, a urea resin, and a glyoxal resin. The toner particle contains fine particles in an interfacial portion between the toner core and the shell layer, and the fine particles have a charge property opposite to that of the toner, or have a volume resistivity lower than both a volume resistivity of the binder resin and a volume resistivity of the shell layer.
    Type: Grant
    Filed: June 26, 2014
    Date of Patent: April 5, 2016
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Yoshio Ozawa, Masami Tsujihiro, Toru Takatsuna, Ryotaro Komada
  • Publication number: 20150293465
    Abstract: A positively chargeable electrostatic latent image developing toner includes a plurality of toner particles each including a toner mother particle and an external additive adhering to a surface of the toner mother particle. The external additive includes metal oxide particles and coat layers that are each disposed over a surface of a corresponding one of the metal oxide particles. The coat layers contain a nitrogen-containing resin. The metal oxide particles contain metal ions having an electronegativity of no greater than 11.
    Type: Application
    Filed: April 7, 2015
    Publication date: October 15, 2015
    Applicant: KYOCERA Document Solutions Inc.
    Inventor: Toru TAKATSUNA
  • Publication number: 20150004537
    Abstract: The present disclosure relates to an electrostatic latent image developing toner containing a toner particle including a toner core containing a binder resin and a shell layer coating a surface of the toner core. The shell layer contains a unit derived from a monomer of a thermosetting resin, and a unit derived from a thermoplastic resin. The thermosetting resin is one or more resins selected from the group of amino resins consisting of a melamine resin, a urea resin, and a glyoxal resin. The toner particle contains fine particles in an interfacial portion between the toner core and the shell layer, and the fine particles have a charge property opposite to that of the toner, or have a volume resistivity lower than both a volume resistivity of the binder resin and a volume resistivity of the shell layer.
    Type: Application
    Filed: June 26, 2014
    Publication date: January 1, 2015
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Yoshio OZAWA, Masami TSUJIHIRO, Toru TAKATSUNA, Ryotaro KOMADA
  • Patent number: 8663885
    Abstract: In a positively chargeable toner, calcium carbonate fine particles having a certain average primary particle diameter are attached to the surface of toner base particles. The toner base particles contain at least a binder resin and a colorant. The calcium carbonate fine particles are ones which had been subjected to a surface treatment with a positively chargeable surface treating agent and a silicone oil. A mass ratio of the positively chargeable surface treating agent to the silicone oil attached to the surface of the calcium carbonate fine particles is set to be 7:3 to 3:7 in terms of the positively chargeable surface treating agent:the silicone oil.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: March 4, 2014
    Assignee: Kyocera Document Solutions Inc.
    Inventor: Toru Takatsuna
  • Publication number: 20130040235
    Abstract: In a positively chargeable toner, calcium carbonate fine particles having a certain average primary particle diameter are attached to the surface of toner base particles. The toner base particles contain at least a binder resin and a colorant. The calcium carbonate fine particles are ones which had been subjected to a surface treatment with a positively chargeable surface treating agent and a silicone oil. A mass ratio of the positively chargeable surface treating agent to the silicone oil attached to the surface of the calcium carbonate fine particles is set to be 7:3 to 3:7 in terms of the positively chargeable surface treating agent:the silicone oil.
    Type: Application
    Filed: August 9, 2012
    Publication date: February 14, 2013
    Applicant: KYOCERA DOCUMENT SOLUTIONS INC.
    Inventor: Toru Takatsuna
  • Publication number: 20080131172
    Abstract: A non-magnetic monocomponent toner is provided for use in a developing device of a non-contact developing method, and is obtained by externally adding an external additive to cylindrical toner particles having a ratio of a cylindrical length (L) to a cylindrical diameter (D), (L/D), within a range from 1 to 2. The non-magnetic monocomponent toner having excellent developability for use in an electrophotograhic apparatus employing a non-contact developing method.
    Type: Application
    Filed: November 29, 2007
    Publication date: June 5, 2008
    Applicant: Kyocera Mita Corporation
    Inventor: Toru Takatsuna
  • Patent number: 7132211
    Abstract: A magnetic toner contains, as a magnetic powder, magnetic iron oxide having an octahedral particle shape and an average particle diameter of 0.21 ?m or larger and containing 18% or more by weight of FeO. The magnetic toner is so prepared as to have a bulk density A (g/cm3) and a magnetic powder content B (% by weight) that fulfill the formulae 0.8?A/B×100?1.6 and 35?B?50. This alleviates the reddishness of images produced with the magnetic toner, and alleviates the disturbance of a thin toner layer on a developing sleeve and thus the fogging resulting therefrom.
    Type: Grant
    Filed: September 9, 2005
    Date of Patent: November 7, 2006
    Assignee: Kyocera Mita Corporation
    Inventors: Hiroko Sugimoto, Takashi Nagai, Toru Takatsuna, Seiji Kikushima
  • Publication number: 20060194133
    Abstract: The magnetic one-component toner of the present invention is used for a developing device having a stainless-steel development sleeve and satisfies the following formulas (i), (ii), (iii) and (iv). The magnetic one-component development is to develop by using the magnetic one-component toner and rotating a stainless-steel development sleeve at a circumferential velocity of not less than 360 mm/second. Thereby, it is possible to inhibit the occurrence of layer irregularity. A ? 11 ( i ) 4 ? B ( ii ) 0.4 ? B A ? 0.8 ( iii ) A × C ? 800 ( iv ) wherein A represents a frictional charge amount (?C/g) after agitating 5 parts by weight of magnetic one-component toner and 95 parts by weight of non-coated ferrite carrier for one minute, B represents a frictional charge amount (?C/g) after agitating 5 parts by weight of magnetic one-component toner and 95 parts by weight of non-coated ferrite carrier for 30 minutes, and C represents a passage rate of toner (%).
    Type: Application
    Filed: February 28, 2006
    Publication date: August 31, 2006
    Inventor: Toru Takatsuna
  • Publication number: 20060035162
    Abstract: A magnetic toner contains, as a magnetic powder, magnetic iron oxide having an octahedral particle shape and an average particle diameter of 0.21 ?m or larger and containing 18% or more by weight of FeO. The magnetic toner is so prepared as to have a bulk density A (g/cm3) and a magnetic powder content B (% by weight) that fulfill the formulae 0.8?A/B×100?1.6 and 35?B?50. This alleviates the reddishness of images produced with the magnetic toner, and alleviates the disturbance of a thin toner layer on a developing sleeve and thus the fogging resulting therefrom.
    Type: Application
    Filed: September 9, 2005
    Publication date: February 16, 2006
    Inventors: Hiroko Sugimoto, Takashi Nagai, Toru Takatsuna, Seiji Kikushima
  • Publication number: 20050053856
    Abstract: A magnetic toner contains, as a magnetic powder, magnetic iron oxide having an octahedral particle shape and an average particle diameter of 0.21 ?m or larger and containing 18% or more by weight of FeO. The magnetic toner is so prepared as to have a bulk density A (g/cm3) and a magnetic powder content B (% by weight) that fulfill the formulae 0.8?A/B×100?1.6 and 35?B?50. This alleviates the reddishness of images produced with the magnetic toner, and alleviates the disturbance of a thin toner layer on a developing sleeve and thus the fogging resulting therefrom.
    Type: Application
    Filed: October 13, 2004
    Publication date: March 10, 2005
    Inventors: Hiroko Sugimoto, Takashi Nagai, Toru Takatsuna, Seiji Kikushima
  • Patent number: 6760560
    Abstract: A developing apparatus has a developer supporting member 41 with a surface roughness RZ in the range from 3.0 to 5.5 &mgr;m and a one-component developer T with a bulk density in the range from 0.35 to 0.55 g/ml, and an image is developed by forming a layer of the developer T on the developer supporting member 41. This makes it possible to form a thin toner layer stably despite changes in ambient conditions, and to prevent low image density and fogging. The absolute value of the amount of electric charge with which the developer T is charged is preferably in the range from 3.0 to 10.0 &mgr;C/g. The developer supporting member 41 is made preferably of stainless steel.
    Type: Grant
    Filed: May 30, 2002
    Date of Patent: July 6, 2004
    Assignees: Kyocera Mita Corporation, Kyocera Corporation
    Inventors: Takashi Nagai, Hidekazu Tamura, Seiji Kikushima, Toru Takatsuna, Hiroko Higuchi, Hiroaki Moriyama, Kouzou Teramoto, Noriya Okamoto
  • Publication number: 20030054275
    Abstract: A magnetic toner contains, as a magnetic powder, magnetic iron oxide having an octahedral particle shape and an average particle diameter of 0.21 &mgr;m or larger and containing 18% or more by weight of FeO. The magnetic toner is so prepared as to have a bulk density A (g/cm3) and a magnetic powder content B (% by weight) that fulfill the formulae 0.8≦A/B×100≦1.6 and 35≦B≦50. This alleviates the reddishness of images produced with the magnetic toner, and alleviates the disturbance of a thin toner layer on a developing sleeve and thus the fogging resulting therefrom.
    Type: Application
    Filed: August 15, 2002
    Publication date: March 20, 2003
    Inventors: Hiroko Sugimoto, Takashi Nagai, Toru Takatsuna, Seiji Kikushima
  • Publication number: 20030031482
    Abstract: A developing apparatus has a developer supporting member 41 with a surface roughness RZ in the range from 3.0 to 5.5 &mgr;m and a one-component developer T with a bulk density in the range from 0.35 to 0.55 g/ml, and an image is developed by forming a layer of the developer T on the developer supporting member 41. This makes it possible to form a thin toner layer stably despite changes in ambient conditions, and to prevent low image density and fogging. The absolute value of the amount of electric charge with which the developer T is charged is preferably in the range from 3.0 to 10.0 &mgr;C/g. The developer supporting member 41 is made preferably of stainless steel.
    Type: Application
    Filed: May 30, 2002
    Publication date: February 13, 2003
    Inventors: Takashi Nagai, Hidekazu Tamura, Seiji Kikushima, Toru Takatsuna, Hiroko Higuchi, Hiroaki Moriyama, Kouzou Teramoto, Noriya Okamoto
  • Publication number: 20030027067
    Abstract: In a magnetic one-component toner containing at least a binder resin, a charge control resin, and a magnetic powder, the charge control resin has a weight-average molecular weight of 1.5×104 or less, contains 8 to 15% by weight of functional groups, and is added in 5 to 20 parts by weight to 100 parts by weight of the binder resin. This makes the toner highly safe for humans and the environment and excellent in fixability and electric chargeability.
    Type: Application
    Filed: January 31, 2002
    Publication date: February 6, 2003
    Inventors: Toru Takatsuna, Takashi Nagai, Hiroko Higuchi, Seiji Kikushima
  • Patent number: 5804347
    Abstract: This invention provides an electrophotographic toner comprising the polyester resin being fixing resin and the electric charge control resin having the functional group that endows positively charging property to the toner, in which the polyester resin has an acid value of not more than 10 mgKOH/g and a hydroxyl value of not more than 40 mgKOH/g, and the functional group is present in 2 to 5 mol % in the electric charge control resin. This electrophotographic toner has stable positively charging property, so that good image is obtainable.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: September 8, 1998
    Assignee: Mita Industrial Co., Ltd.
    Inventors: Kazushige Inoue, Toru Takatsuna, Yukihiro Mori, Etsuro Nakagawa, Hiroko Higuchi