Patents by Inventor Junko Yoshikawa

Junko Yoshikawa 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: 7190925
    Abstract: A developer supply container for supplying a developer detachably set in an image forming apparatus, the developer supply container includes a main body for containing the developer; a discharge opening, provided in the main body, for discharging the developer; a plurality of feeding projections, provided projected from a curved inner surface, for feeding the developer in the main body toward the discharge opening with rotation of the main body, wherein each of the projections are linear without twisting.
    Type: Grant
    Filed: August 31, 2004
    Date of Patent: March 13, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tetsuo Isomura, Yutaka Ban, Yusuke Yamada, Kazuhiko Omata, Junko Yoshikawa, Hironori Minagawa
  • Patent number: 7054581
    Abstract: A developer supply container substantially non-rotatably mountable, with a developing device for developing an electrostatic image with a developer, to a rotatable member provided in an image forming apparatus, the developer supply container being adapted to supply a developer into the developing device therefrom with rotation of the rotatable member, the developer supply container includes a container body for containing the developer; a discharging opening, formed in a peripheral surface of the container body, for permitting downward discharge of the developer; a feeding portion, provided on an inside surface of the container body, for feeding the developer in a feeding direction toward the discharge opening with rotation of the rotatable member; and a developer movement constraining portion, provided adjacent a position opposed to a position of the discharge opening on the inside surface of the container body, independently of said feeding portion, for constraining the developer which is reversed into the
    Type: Grant
    Filed: March 10, 2004
    Date of Patent: May 30, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Junko Yoshikawa, Tetsuo Isomura
  • Patent number: 6987942
    Abstract: A toner supplying kit for being detachably set in an image forming apparatus to supply toner thereto, the toner supplying kit includes a toner container for containing toner; a discharge opening, provided in the toner container, for discharging the toner; plural feeding projections, projected inwardly in the toner container, for feeding the toner in the toner container toward the discharge opening with rotation of the toner container, wherein a uniaxial collapse stress of the toner when a vertical stress of 128 g/cm2 is applied thereto is 2.0-8.0 g/cm2.
    Type: Grant
    Filed: April 22, 2003
    Date of Patent: January 17, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Junko Yoshikawa, Yutaka Ban, Tetsuo Isomura, Hironori Minagawa
  • Patent number: 6963713
    Abstract: A developer supply container supplies a developer detachably set in an image forming apparatus. The developer supply container includes a main body for containing the developer; a discharge opening, which is provided in the main body, for discharging the developer; and a plurality of feeding projections, which are disposed so as to project from a curved inner surface of the main body, for feeding the developer in the main body toward the discharge opening with rotation of the main body. Each of the projections is linear without being twisted, wherein adjacent ones of the plurality of feeding projections include portions, which overlap each other as seen in a direction of an axis of rotation of the main body.
    Type: Grant
    Filed: April 23, 2003
    Date of Patent: November 8, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tetsuo Isomura, Yutaka Ban, Yusuke Yamada, Kazuhiko Omata, Junko Yoshikawa, Hironori Minagawa
  • Patent number: 6929894
    Abstract: A toner is disclosed which is composed of toner particles containing at least a binder resin, a colorant and a wax, and an external additive. The wax has, in its DSC endothermic curve, a maximum endothermic peak at 55° C. to 80° C. within the temperature range from 30° C. to 160° C., the maximum endothermic peak having a half width of from 2° C. to 7° C., and the binder resin is composed chiefly of a polyester resin. The toner has a dynamic elastic modulus from 5×102 to 1×105 dN/m2 at 140° C., and its ratio to a dynamic elastic modulus at 170° C. is from 0.05 to 50, and the toner contains 10 to 20% by weight of THF-insoluble matter A of a binder resin component after 8 hours from the start of extraction and 1 to 10% by weight of THF-insoluble matter B of the binder resin component after 24 hours from the start of extraction, the ratio of A to B, B/A, being from 0.1 to 0.8. Also disclosed is a fixing method making use of this toner.
    Type: Grant
    Filed: July 10, 2002
    Date of Patent: August 16, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Nobuyoshi Sugahara, Masaaki Taya, Junko Yoshikawa, Takayuki Itakura, Yojiro Hotta
  • Patent number: 6922540
    Abstract: A developer supply kit for supplying a developer to an image forming apparatus includes a container for accommodating a developer; an opening provided in the container to permit discharging of the developer; and a feeding member, provided in the container, for feeding the developer by rotation thereof. The feeding member includes a lift portion for lifting the toner in the container, a guiding portion for guiding the toner lifted by the lift portion downwardly toward the opening, and a falling portion for letting the toner lifted by the lifting portion fall without feeding it toward the opening with rotation of the feeding member. The developer has an adhering strength which is not less than 0.60 g/cm2 and less than 3.00 g/cm2 after a vertical pressure of 128.4 g/cm2 is imparted to a layer of the developer.
    Type: Grant
    Filed: October 3, 2002
    Date of Patent: July 26, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Junko Yoshikawa, Yusuke Yamada
  • Publication number: 20050025529
    Abstract: A developer supply container for supplying a developer detachably set in an image forming apparatus, the developer supply container includes a main body for containing the developer; a discharge opening, provided in the main body, for discharging the developer; a plurality of feeding projections, provided projected from a curved inner surface, for feeding the developer in the main body toward the discharge opening with rotation of the main body, wherein each of the projections are linear without twisting.
    Type: Application
    Filed: August 31, 2004
    Publication date: February 3, 2005
    Applicant: Canon Kabushiki Kaisha
    Inventors: Tetsuo Isomura, Yutaka Ban, Yusuke Yamada, Kazuhiko Omata, Junko Yoshikawa, Hironori Minagawa
  • Publication number: 20040234297
    Abstract: A developer supply container substantially non-rotatably mountable, with a developing device, to a rotatable member provided in an image forming apparatus, said developer supply container being adapted to supply a developer into the developing device therefrom with rotation of the rotatable member, said developer supply container includes a container body for containing the developer; a discharging opening, formed in a peripheral surface of said container body, for permitting downward discharge of the developer; a feeding portion, provided in said container body, for feeding the developer in a feeding direction toward said discharge opening with rotation of said rotatable member; and a developer movement constraining portion, provided adjacent a position facing said discharge opening within in said container body, for constraining the developer which is reversed into said container body through said discharge opening when said discharge opening faces upward with rotation of said rotatable member, from moving
    Type: Application
    Filed: March 10, 2004
    Publication date: November 25, 2004
    Applicant: Canon Kabushiki Kaisha
    Inventors: Junko Yoshikawa, Tetsuo Isomura
  • Publication number: 20040052553
    Abstract: A developer supply container for supplying a developer detachably set in an image forming apparatus, the developer supply container includes a main body for containing the developer; a discharge opening, provided in the main body, for discharging the developer; a plurality of feeding projections, provided projected from a curved inner surface, for feeding the developer in the main body toward the discharge opening with rotation of the main body, wherein each of the projections are linear without twisting.
    Type: Application
    Filed: April 23, 2003
    Publication date: March 18, 2004
    Applicant: Canon Kabushiki Kaisha
    Inventors: Tetsuo Isomura, Yutaka Ban, Yusuke Yamada, Kazuhiko Omata, Junko Yoshikawa, Hironori Minagawa
  • Publication number: 20040033087
    Abstract: A toner supplying kit for being detachably set in an image forming apparatus to supply toner thereto, said toner supplying kin includes a toner container for containing toner; a discharge opening, provided in said toner container, for discharging the toner; a plurality of feeding projections, projected inwardly in said toner container, for feeding the toner in said toner container toward said discharge opening with rotation of said toner container, wherein a uniaxial collapse stress of the toner when a vertical stress of 128 g/cm2 is applied thereto is 2.0-8.0 g/cm2.
    Type: Application
    Filed: April 22, 2003
    Publication date: February 19, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Junko Yoshikawa, Yutaka Ban, Tetsuo Isomura, Hironori Minagawa
  • Publication number: 20040009420
    Abstract: A toner is disclosed which is composed of toner particles containing at least a binder resin, a colorant and a wax, and an external additive. The wax has, in its DSC endothermic curve, a maximum endothermic peak at 55° C. to 80° C. within the temperature range from 30° C. to 160° C., the maximum endothermic peak having a half width of from 2° C. to 7° C., and the binder resin is composed chiefly of a polyester resin. The toner has a dynamic elastic modulus from 5×102 to 1×105 dN/m2 at 140° C., and its ratio to a dynamic elastic modulus at 170° C. is from 0.05 to 50, and the toner contains 10 to 20% by weight of THF-insoluble matter A of a binder resin component after 8 hours from the start of extraction and 1 to 10% by weight of THF-insoluble matter B of the binder resin component after 24 hours from the start of extraction, the ratio of A to B, B/A, being from 0.1 to 0.8. Also disclosed is a fixing method making use of this toner.
    Type: Application
    Filed: July 10, 2002
    Publication date: January 15, 2004
    Inventors: Nobuyoshi Sugahara, Masaaki Taya, Junko Yoshikawa, Takayuki Itakura, Yojiro Hotta
  • Patent number: 6653038
    Abstract: A toner is formed of toner particles each comprising at least a binder resin, a colorant and a wax, and inorganic fine powder. The toner is characterized by (a) containing a sulfur-containing polymer, and (b) showing dielectric loss tangent (tan&dgr;) values at 100 kHz assuming a maximum of 2.5×10−2 to 8×10−2 in a temperature range of 100 to 130° C. Because of the combination of the features (a) and (b), the toner can exhibit a good combination of developing performances and fixing performances.
    Type: Grant
    Filed: March 15, 2002
    Date of Patent: November 25, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Satoshi Matsunaga, Junko Yoshikawa, Ryota Kashiwabara
  • Patent number: 6613490
    Abstract: A toner exhibiting good balance of low-temperature fixability, an anti-offset characteristic and a developing performance in continuous image formation is formed of at least a binder resin, a colorant and a wax. The toner exhibits a dielectric loss tangent showing a maximum of 6.0×10−2 to 10.0×10−2 in a temperature range of 90 to 125° C. The toner provides a DSC curve showing at least one heat-absorption peak or shoulder in a temperature range of 85 to 140° C. on temperature increase according to differential scanning calorimetry (DSC). The binder resin comprises a hybrid resin having a vinyl polymer unit and a polyester unit.
    Type: Grant
    Filed: October 29, 2001
    Date of Patent: September 2, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Satoshi Matsunaga, Yuichi Mizoh, Junko Yoshikawa, Ryota Kashiwabara
  • Patent number: 6593052
    Abstract: A toner containing toner particles and an inorganic fine powder; the toner particles containing at least a binder resin, a colorant, a sulfur-containing resin, and a wax; the binder resin containing a hybrid resin component containing a vinyl type polymer unit and a polyester unit, and the sulfur-containing resin being a resin selected from the group consisting of sulfur-containing polymers and sulfur-containing copolymers
    Type: Grant
    Filed: July 27, 2001
    Date of Patent: July 15, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Junko Yoshikawa, Yuichi Mizoo, Satoshi Matsunaga, Tadashi Dojo, Nene Shibayama, Ryota Kashiwabara
  • Publication number: 20030081967
    Abstract: A developer supply kit for supplying a developer to an image forming apparatus, the developer supply kit includes a container for accommodating a developer; an opening provided in the container to permit discharging of the developer; a feeding member, provided in the container, for feeding the developer by rotation thereof; wherein the feeding member includes a lift portion for lifting the toner in the container, a guiding portion for guiding the toner lifted by the collecting portion downwardly toward the opening, and a falling portion for letting the toner lifted by the lifting portion fall without feeding it toward the opening with rotation of the feeding member, wherein the developer has an adhering strength which is not less than 0.60 g/cm2 and less than 3.00 g/cm2 after a vertical pressure of 128.4 g/cm2 is imparted to a layer of the developer.
    Type: Application
    Filed: October 3, 2002
    Publication date: May 1, 2003
    Applicant: Canon Kabushiki Kaisha
    Inventors: Junko Yoshikawa, Yusuke Yamada
  • Publication number: 20030044708
    Abstract: A toner is formed of toner particles each comprising at least a binder resin, a colorant and a wax, and inorganic fine powder. The toner is characterized by (a) containing a sulfur-containing polymer, and (b) showing dielectric loss tangent (tan&dgr;) values at 100 kHz assuming a maximum of 2.5×10−2 to 8×10−2 in a temperature range of 100 to 130° C. Because of the combination of the features (a) and (b), the toner can exhibit a good combination of developing performances and fixing performances.
    Type: Application
    Filed: March 15, 2002
    Publication date: March 6, 2003
    Inventors: Satoshi Matsunaga, Junko Yoshikawa, Ryota Kashiwabara
  • Publication number: 20020098433
    Abstract: A toner exhibiting good balance of low-temperature fixability, an anti-offset characteristic and a developing performance in continuous image formation is formed of at least a binder resin, a colorant and a wax. The toner exhibits a dielectric loss tangent showing a maximum of 6.0×10−2 to 10.0×10−2 in a temperature range of 90 to 125° C. The toner provides a DSC curve showing at least one heat-absorption peak or shoulder in a temperature range of 85 to 140° C. on temperature increase according to differential scanning calorimetry (DSC). The binder resin comprises a hybrid resin having a vinyl polymer unit and a polyester unit.
    Type: Application
    Filed: October 29, 2001
    Publication date: July 25, 2002
    Inventors: Satoshi Matsunaga, Yuichi Mizoh, Junko Yoshikawa, Ryota Kashiwabara
  • Publication number: 20020045120
    Abstract: A toner containing toner particles and an inorganic fine powder; the toner particles containing at least a binder resin, a colorant, a sulfur-containing resin, and a wax; the binder resin containing a hybrid resin component containing a vinyl type polymer unit and a polyester unit, and the sulfur-containing resin being a resin selected from the group consisting of sulfur-containing polymers and sulfur-containing copolymers
    Type: Application
    Filed: July 27, 2001
    Publication date: April 18, 2002
    Inventors: Junko Yoshikawa, Yuichi Mizoo, Satoshi Matsunaga, Tadashi Dojo, Nene Shibayama, Ryota Kashiwabara
  • Patent number: 6326114
    Abstract: A toner includes at least a polyester resin having a carboxyl group, a coloring agent, 0.1-10 mass % of a metal salicylate compound with respect to a mass of the toner and 20-400 ppm of a hindered phenol with respect to the mass of the toner.
    Type: Grant
    Filed: April 13, 2000
    Date of Patent: December 4, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takayuki Itakura, Masaaki Taya, Wakashi Iida, Junko Yoshikawa, Nobuyoshi Sugahara
  • Patent number: D490844
    Type: Grant
    Filed: October 15, 2003
    Date of Patent: June 1, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ayatomo Okino, Masashige Tamura, Junko Yoshikawa