Patents by Inventor Seishi Ojima

Seishi Ojima 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: 10126669
    Abstract: A composite core of a toner particle is a composite of a toner core containing a polyester resin and a plurality of resin particles each containing a first resin. A shell layer partially covering a surface of the composite core is a film containing a second resin. The first resin has a glass transition point that is 10° C. or more higher than a glass transition point of the second resin. The plurality of resin particles each have a particle diameter that is 1.5 times or more greater than a thickness of the shell layer. An amount of the resin particles is at least 0.3 parts by mass and no greater than 2.0 parts by mass relative to 100 parts by mass of the toner cores. The resin particles have a positive zeta potential at pH 4.
    Type: Grant
    Filed: July 11, 2017
    Date of Patent: November 13, 2018
    Assignee: KYOCERA Document Solutions Inc.
    Inventor: Seishi Ojima
  • Patent number: 10018932
    Abstract: An electrostatic latent image developing toner includes toner particles each including a toner core (11) and a shell layer (12) disposed over a surface of the toner core (11). The toner core (11) contains a polyester resin. The shell layer (12) includes: first resin particles (12a) having a number average primary particle diameter of at least 30 nm and less than 70 nm and a glass transition point of less than 80° C.; and second resin particles (12b) having a number average primary particle diameter of 70-200 nm and a glass transition point of at least 80° C. A percentage of an area of the toner core (11) covered with the first resin particles (12a) relative to a surface area of the toner core (11) is 40-80%. A ratio of total mass of the second resin particles (12b) to total mass of the first resin particles (12a) is 0.5-2.0.
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: July 10, 2018
    Assignee: KYOCERA Document Solutions Inc.
    Inventor: Seishi Ojima
  • Publication number: 20180188665
    Abstract: An electrostatic latent image developing toner includes toner particles each including a toner core (11) and a shell layer (12) disposed over a surface of the toner core (11). The toner core (11) contains a polyester resin. The shell layer (12) includes: first resin particles (12a) having a number average primary particle diameter of at least 30 nm and less than 70 nm and a glass transition point of less than 80° C.; and second resin particles (12b) having a number average primary particle diameter of 70-200 nm and a glass transition point of at least 80° C. A percentage of an area of the toner core (11) covered with the first resin particles (12a) relative to a surface area of the toner core (11) is 40-80%. A ratio of total mass of the second resin particles (12b) to total mass of the first resin particles (12a) is 0.5-2.0.
    Type: Application
    Filed: September 28, 2016
    Publication date: July 5, 2018
    Applicant: KYOCERA Document Solutions Inc.
    Inventor: Seishi OJIMA
  • Patent number: 10007202
    Abstract: A positively chargeable toner includes a plurality of toner particles each including a core and a shell layer disposed over a surface of the core. The core contains a polyester resin. The shell layer covers at least 40% and no greater than 80% of an area of the surface of the core, ?(4) is greater than 0 V. ?(6) is less than 0 V. A relationship represented by |?(3)??(4)|>|?(6)??(7)| is satisfied. ?(3), ?(4), ?(6), and ?(7) represent zeta potentials of the positively chargeable toner with the toner particles having no external additive. ?(3), ?(4), ?(6), and ?(7) are respectively measured in an aqueous medium at pH 3, pH 4, pH 6, and pH 7.
    Type: Grant
    Filed: July 1, 2016
    Date of Patent: June 26, 2018
    Assignee: KYOCERA Document Solutions Inc.
    Inventor: Seishi Ojima
  • Publication number: 20180031993
    Abstract: A positively chargeable toner includes a plurality of toner particles each including a core and a shell layer disposed over a surface of the core. The core contains a polyester resin. The shell layer covers at least 40% and no greater than 80% of an area of the surface of the core, ?(4) is greater than 0 V. ?(6) is less than 0 V. A relationship represented by |?(3)??(4)|>|?(6)??(7)| is satisfied. ?(3), ?(4), ?(6), and ?(7) represent zeta potentials of the positively chargeable toner with the toner particles having no external additive. ?(3), ?(4), ?(6), and ?(7) are respectively measured in an aqueous medium at pH 3, pH 4, pH 6, and pH 7.
    Type: Application
    Filed: July 1, 2016
    Publication date: February 1, 2018
    Applicant: KYOCERA Document Solutions Inc.
    Inventor: Seishi OJIMA
  • Publication number: 20180024454
    Abstract: A composite core of a toner particle is a composite of a toner core containing a polyester resin and a plurality of resin particles each containing a first resin. A shell layer partially covering a surface of the composite core is a film containing a second resin. The first resin has a glass transition point that is 10° C. or more higher than a glass transition point of the second resin. The plurality of resin particles each have a particle diameter that is 1.5 times or more greater than a thickness of the shell layer. An amount of the resin particles is at least 0.3 parts by mass and no greater than 2.0 parts by mass relative to 100 parts by mass of the toner cores. The resin particles have a positive zeta potential at pH 4.
    Type: Application
    Filed: July 11, 2017
    Publication date: January 25, 2018
    Applicant: KYOCERA Document Solutions Inc.
    Inventor: Seishi OJIMA
  • Patent number: 9535352
    Abstract: An electrostatic latent image developing toner includes toner particles that each include a toner mother particle. The toner mother particle includes a toner core, a shell layer disposed over a surface of the toner core, and inorganic particles. The inorganic particles are located at an interface between the toner core and the shell layer, or within the shell layer. The shell layer contains a thermosetting component. The toner mother particle has a BET specific surface area of at least 0.95 m2/g.
    Type: Grant
    Filed: October 26, 2015
    Date of Patent: January 3, 2017
    Assignee: KYOCERA Document Solutions Inc.
    Inventor: Seishi Ojima
  • Patent number: 9436109
    Abstract: A method of manufacturing resin particles uses a microreactor to mix first and second stock solutions, and to aggregate resin fine-particles to obtain resin particles. The microreactor includes stationary and rotating discs that are two discoid discs and that are disposed so that a gap is formed between circular surfaces of the two discs when the resin particles are manufactured, a first stock solution feed part that feeds the first stock solution from an end of the gap into the gap, and one or more second stock solution feed parts that are formed at the opposite side of the first stock solution feed part based on the center of the circular surface of the stationary disc by spatially connecting top and bottom surfaces of the stationary disc, and that feed the second stock solution containing an aggregating agent from the top surface side of the stationary disc to the gap.
    Type: Grant
    Filed: May 23, 2013
    Date of Patent: September 6, 2016
    Assignee: KYOCERA Document Solutions Inc.
    Inventor: Seishi Ojima
  • Publication number: 20160116856
    Abstract: An electrostatic latent image developing toner includes toner particles that each include a toner mother particle. The toner mother particle includes a toner core, a shell layer disposed over a surface of the toner core, and inorganic particles. The inorganic particles are located at an interface between the toner core and the shell layer, or within the shell layer. The shell layer contains a thermosetting component. The toner mother particle has a BET specific surface area of at least 0.95 m2/g.
    Type: Application
    Filed: October 26, 2015
    Publication date: April 28, 2016
    Applicant: KYOCERA Document Solutions Inc.
    Inventor: Seishi OJIMA
  • Patent number: 9250551
    Abstract: An electrostatic latent image developing toner is manufactured by mixing an aqueous medium dispersion liquid (X) containing negatively chargeable toner cores and an aqueous medium dispersion liquid (Y) containing positively chargeable resin particulates, followed by stirring the mixture liquid to form shell layers each on a surface of the toner cores with the resin particulates. The shell layers are formed with the resin particulates subjected to a stirring treatment together with an anionic surfactant.
    Type: Grant
    Filed: March 28, 2014
    Date of Patent: February 2, 2016
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Seishi Ojima, Ryotaro Komada
  • Publication number: 20140295345
    Abstract: An electrostatic latent image developing toner is manufactured by mixing an aqueous medium dispersion liquid (X) containing negatively chargeable toner cores and an aqueous medium dispersion liquid (Y) containing positively chargeable resin particulates, followed by stirring the mixture liquid to form shell layers each on a surface of the toner cores with the resin particulates. The shell layers are formed with the resin particulates subjected to a stirring treatment together with an anionic surfactant.
    Type: Application
    Filed: March 28, 2014
    Publication date: October 2, 2014
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Seishi OJIMA, Ryotaro KOMADA
  • Publication number: 20130323635
    Abstract: A method of manufacturing resin particles uses a microreactor to mix first and second stock solutions, and to aggregate resin fine-particles to obtain resin particles. The microreactor includes stationary and rotating discs that are two discoid discs and that are disposed so that a gap is formed between circular surfaces of the two discs when the resin particles are manufactured, a first stock solution feed part that feeds the first stock solution from an end of the gap into the gap, and one or more second stock solution feed parts that are formed at the opposite side of the first stock solution feed part based on the center of the circular surface of the stationary disc by spatially connecting top and bottom surfaces of the stationary disc, and that feed the second stock solution containing an aggregating agent from the top surface side of the stationary disc to the gap.
    Type: Application
    Filed: May 23, 2013
    Publication date: December 5, 2013
    Applicant: KYOCERA Document Solutions Inc.
    Inventor: Seishi Ojima
  • Patent number: 8583015
    Abstract: A developing device includes: a developer carrying body which supplies developer to a predetermined image carrying body; a layer thickness regulating member which is made of a magnetic material, which has a layer thickness regulating face opposing the developer carrying body so as to form a predetermined gap between the layer thickness regulating face and the developer carrying body and regulating the layer thickness of the developer on the developer carrying body, and which forms a magnetic path between the layer thickness regulating face and the developer carrying body; an installation member on which the layer thickness regulating member is installed; and an elastic sheet member arranged in the gap in a state of contact with a surface of the developer carrying body.
    Type: Grant
    Filed: September 13, 2010
    Date of Patent: November 12, 2013
    Assignee: Kyocera Mita Corporation
    Inventors: Seishi Ojima, Minoru Wada, Sayo Mabuchi
  • Patent number: 8494418
    Abstract: The development device includes a developer storage part storing a developer, a developer carrier having a carrying surface for carrying the developer and a first magnet, and receiving the developer from the developer storage part on the carrying surface while rotating in a predetermined direction, and supplying the developer to a predetermined image carrier, a magnetic member formed from a magnetic material, forming a predetermined regulatory gap with the carrying surface, and arranged opposite to the first magnet, a second magnet disposed more upstream than the magnetic member when viewed from the rotating direction of the developer carrier, and having a magnetic pole of the same polarity as the first magnet, and a deterioration suppressing part suppressing deterioration of the developer transported to the regulatory gap along with the rotation of the developer carrier.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: July 23, 2013
    Assignee: Kyocera Mita Corporation
    Inventors: Sayo Mabuchi, Minoru Wada, Seishi Ojima
  • Patent number: 8428497
    Abstract: A developing device includes a developer storing portion, a developer carrying body, a first regulating member having a first regulating surface regulating a layer thickness of the developer on the developer carrying body, a second regulating member having a second regulating surface that is set so as to gradually become apart from the developer carrying body toward the upstream side with respect to the rotation direction of the developer carrying body to regulate an amount of the developer conveyed to the first regulating surface, the second regulating surface being arranged with a step formed between the second regulating surface and the first regulating surface, and a sheet member so attached to the second regulating surface as to cover at least a portion of the step between the first regulating surface and the second regulating surface.
    Type: Grant
    Filed: September 13, 2010
    Date of Patent: April 23, 2013
    Assignee: Kyocera Mita Corporation
    Inventors: Minoru Wada, Seishi Ojima, Sayo Mabuchi
  • Patent number: 8190072
    Abstract: A developing device includes a container storing a two-component developer including a toner and a carrier, a toner carrying body carrying the toner in the container and supplying the toner to a predetermined image carrying body by rotation, a restricting member held in press contact with the toner carrying body, and a restricting nip section formed between the toner carrying body and the restricting member. The restricting nip section selects only the toner in the two-component developer to form a uniform toner layer on the toner carrying body.
    Type: Grant
    Filed: July 13, 2009
    Date of Patent: May 29, 2012
    Assignee: Kyocera Mita Corporation
    Inventors: Minoru Wada, Taisuke Nagao, Hisashi Mukataka, Seishi Ojima
  • Publication number: 20110150539
    Abstract: The development device includes a developer storage part storing a developer, a developer carrier having a carrying surface for carrying the developer and a first magnet, and receiving the developer from the developer storage part on the carrying surface while rotating in a predetermined direction, and supplying the developer to a predetermined image carrier, a magnetic member formed from a magnetic material, forming a predetermined regulatory gap with the carrying surface, and arranged opposite to the first magnet, a second magnet disposed more upstream than the magnetic member when viewed from the rotating direction of the developer carrier, and having a magnetic pole of the same polarity as the first magnet, and a deterioration suppressing part suppressing deterioration of the developer transported to the regulatory gap along with the rotation of the developer carrier.
    Type: Application
    Filed: December 17, 2010
    Publication date: June 23, 2011
    Applicant: KYOCERA MITA CORPORATION
    Inventors: Sayo Mabuchi, Minoru Wada, Seishi Ojima
  • Publication number: 20110064485
    Abstract: A developing device includes: a developer carrying body which supplies developer to a predetermined image carrying body; a layer thickness regulating member which is made of a magnetic material, which has a layer thickness regulating face opposing the developer carrying body so as to form a predetermined gap between the layer thickness regulating face and the developer carrying body and regulating the layer thickness of the developer on the developer carrying body, and which forms a magnetic path between the layer thickness regulating face and the developer carrying body; an installation member on which the layer thickness regulating member is installed; and an elastic sheet member arranged in the gap in a state of contact with a surface of the developer carrying body.
    Type: Application
    Filed: September 13, 2010
    Publication date: March 17, 2011
    Applicant: KYOCERA MITA CORPORATION
    Inventors: Seishi Ojima, Minoru Wada, Sayo Mabuchi
  • Publication number: 20110064484
    Abstract: A developing device includes a developer storing portion, a developer carrying body, a first regulating member having a first regulating surface regulating a layer thickness of the developer on the developer carrying body, a second regulating member having a second regulating surface that is set so as to gradually become apart from the developer carrying body toward the upstream side with respect to the rotation direction of the developer carrying body to regulate an amount of the developer conveyed to the first regulating surface, the second regulating surface being arranged with a step formed between the second regulating surface and the first regulating surface, and a sheet member so attached to the second regulating surface as to cover at least a portion of the step between the first regulating surface and the second regulating surface.
    Type: Application
    Filed: September 13, 2010
    Publication date: March 17, 2011
    Applicant: KYOCERA MITA CORPORATION
    Inventors: Minoru Wada, Seishi Ojima, Sayo Mabuchi
  • Publication number: 20100014879
    Abstract: A developing device includes a container storing a two-component developer including a toner and a carrier, a toner carrying body carrying the toner in the container and supplying the toner to a predetermined image carrying body by rotation, a restricting member held in press contact with the toner carrying body, and a restricting nip section formed between the toner carrying body and the restricting member. The restricting nip section selects only the toner in the two-component developer to form a uniform toner layer on the toner carrying body.
    Type: Application
    Filed: July 13, 2009
    Publication date: January 21, 2010
    Applicant: KYOCERA MITA CORPORATION
    Inventors: Minoru Wada, Taisuke Nagao, Hisashi Mukataka, Seishi Ojima