Patents by Inventor Akihito Ikegawa

Akihito Ikegawa 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: 7604706
    Abstract: An initial resin substrate is formed by laminating resin layers, and one surface of the initial substrate is heated and pressed by a molding die to mold a projected and dented surface such that substantially no deformation occurs on the resin layer providing a surface opposed to the one surface of the initial substrate. A reversible image display medium is produced by a method comprising the steps of accommodating a dry developer into the concavities and fixing a second substrate to the first substrate using an adhesive. Alternatively a reversible image display medium may be produced by, e.g.
    Type: Grant
    Filed: March 29, 2002
    Date of Patent: October 20, 2009
    Assignee: Minolta Co., Ltd.
    Inventors: Kenji Otokawa, Denji Nota, Akihito Ikegawa, Keyaki Yogome, Takaji Kurita
  • Patent number: 7436379
    Abstract: Disclosed is a reversible image display medium which can be repeatedly used and can display high quality images, in which cells between the two substrates accommodate a dry developer containing at least two kinds of frictionally chargeable dry developing particles having different chargeable polarities and different optical reflection densities; images are displayed by forming an electrostatic latent image corresponding to the image to be formed on one of the two substrates to drive the developing particles in an electrostatic field based on the electrostatic latent image; a developer-facing surface of one of the substrates has a surface resistivity of at least 1×1012 ohm/square; a developer-facing surface of the opposite substrate has a surface resistivity from 1×106 ohm/square to 1×1012 ohm/square; a developer-facing surface of one of the substrates has a surface average median roughness Ra of 0.2 ?m to 0.
    Type: Grant
    Filed: May 16, 2005
    Date of Patent: October 14, 2008
    Assignee: Minolta Co., Ltd.
    Inventors: Masahiko Matsuura, Hiroshi Mizuno, Akihito Ikegawa, Masaharu Kanazawa, Keyaki Yogome, Takaji Kurita
  • Publication number: 20080018021
    Abstract: An initial resin substrate is formed by laminating resin layers, and one surface of the initial substrate is heated and pressed by a molding die to mold a projected and dented surface such that substantially no deformation occurs on the resin layer providing a surface opposed to the one surface of the initial substrate. A reversible image display medium is produced by a method comprising the steps of accommodating a dry developer into the concavities and fixing a second substrate to the first substrate using an adhesive. Alternatively a reversible image display medium may be produced by, e.g.
    Type: Application
    Filed: September 20, 2007
    Publication date: January 24, 2008
    Applicant: MINOLTA CO., LTD.
    Inventors: Kenji OTOKAWA, Denji Nota, Akihito IKEGAWA, Keyaki YOGOME, Takaji KUBITA
  • Publication number: 20050212748
    Abstract: Disclosed is a reversible image display medium which can be repeatedly used and can display high quality images, in which cells between the two substrates accommodate a dry developer containing at least two kinds of frictionally chargeable dry developing particles having different chargeable polarities and different optical reflection densities; images are displayed by forming an electrostatic latent image corresponding to the image to be formed on one of the two substrates to drive the developing particles in an electrostatic field based on the electrostatic latent image; a developer-facing surface of one of the substrates has a surface resistivity of at least 1×1012 ohm/square; a developer-facing surface of the opposite substrate has a surface resistivity from 1×106 ohm/square to 1×1012 ohm/square; a developer-facing surface of one of the substrates has a surface average median roughness Ra of 0.2 ?m to 0.
    Type: Application
    Filed: May 16, 2005
    Publication date: September 29, 2005
    Applicant: MINOLTA CO., LTD.
    Inventors: Masahiko Matsuura, Hiroshi Mizuno, Akihito Ikegawa, Masaharu Kanazawa, Keyaki Yogome, Takaji Kurita
  • Publication number: 20050179643
    Abstract: A method and apparatus capable of displaying a high-quality image using a reversible image display medium in which a cell(s) formed between two substrates accommodates at least two kinds of frictionally chargeable dry developing particles having different chargeable polarities and different optical reflection densities. in image display, an electric field strength of, e.g., 0.3 V/?m to 3.0 V/?m is applied to the developer. An oscillating force (e.g. oscillating magnetic filed) is applicable and the oscillating force is substantially stopped during application of the electrostatic field. After completion of the electrostatic field, the surface of the medium on the image observation side may be charged to a potential holding the displayed image. Optionally before image display, an alternating electric field may be applied to stir the developer for initialization of the medium.
    Type: Application
    Filed: February 17, 2005
    Publication date: August 18, 2005
    Applicant: MINOLTA CO., LTD.
    Inventors: Masahiko Matsuura, Hiroshi Mizuno, Akihito Ikegawa, Masaharu Kanazawa, Keyaki Yogome, Takaji Kurita
  • Patent number: 6922204
    Abstract: The invention provides an image display medium comprising: a first transparent substrate disposed on an observation side; a second substrate disposed on a further side from the observation side than the first substrate; and a display layer formed between the first substrate and the second substrate and containing a plurality of developer particles; the first substrate including a color filter having at least one group of a plurality of light-transmitting filter films of different colors. The invention also provides an image recording apparatus including a recording head for recording an image on the medium and a positioning device for positioning the filter films of the color filter and the recording head. The invention further provides an image recording method comprising the steps of positioning the filter films of the medium and the recording head, and recording an image by the recording head on the medium having the filter films positioned.
    Type: Grant
    Filed: April 4, 2003
    Date of Patent: July 26, 2005
    Assignee: Minolta Co., Ltd.
    Inventors: Masaharu Kanazawa, Keyaki Yogome, Akihito Ikegawa
  • Patent number: 6900789
    Abstract: Disclosed is a reversible image display medium which can be repeatedly used and can display high quality images, in which cells between the two substrates accommodate a dry developer containing at least two kinds of frictionally chargeable dry developing particles having different chargeable polarities and different optical reflection densities; images are displayed by forming an electrostatic latent image corresponding to the image to be formed on one of the two substrates to drive the developing particles in an electrostatic field based on the electrostatic latent image; a developer-facing surface of one of the substrates has a surface resistivity of at least 1×1012 ohm/square; a developer-facing surface of the opposite substrate has a surface resistivity from 1×106 ohm/square to 1×1012 ohm/square; a developer-facing surface of one of the substrates has a surface average median roughness Ra of 0.2 ?m to 0.
    Type: Grant
    Filed: November 16, 2001
    Date of Patent: May 31, 2005
    Assignee: Minolta Co., Ltd.
    Inventors: Masahiko Matsuura, Hiroshi Mizuno, Akihito Ikegawa, Masaharu Kanazawa, Keyaki Yogome, Takaji Kurita
  • Patent number: 6881307
    Abstract: In order to provide an image creating apparatus which is driven at a high speed by a low voltage and realizes high contrast, the image creating apparatus of the present invention applies a voltage selectively to surfaces of arranged plural polymeric electrolyte films and generate a potential difference between both surfaces of the polymeric electrolyte films to which the voltage is applied to deform the polymeric electrolyte films. This image creating apparatus can provide an optical shutter of an image recording apparatus and a reflection or transmitting type image display device.
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: April 19, 2005
    Assignee: Minolta Co., Ltd.
    Inventor: Akihito Ikegawa
  • Patent number: 6862016
    Abstract: A method and apparatus capable of displaying a high-quality image using a reversible image display medium in which a cell(s) formed between two substrates accommodates at least two kinds of frictionally chargeable dry developing particles having different chargeable polarities and different optical reflection densities in image display, an electric field strength of, e.g., 0.3 V/?m to 3.0 V/?m is applied to the developer. An oscillating force (e.g. oscillating magnetic filed) is applicable and the oscillating force is substantially stopped during application of the electrostatic field. After completion of the electrostatic field, the surface of the medium on the image observation side may be charged to a potential holding the displayed image. Optionally, before image display, an alternating electric field may be applied to stir the developer for initialization of the medium.
    Type: Grant
    Filed: November 16, 2001
    Date of Patent: March 1, 2005
    Assignee: Minolta Co., Ltd.
    Inventors: Masahiko Matsuura, Hiroshi Mizuno, Akihito Ikegawa, Masaharu Kanazawa, Keyaki Yogome, Takaji Kurita
  • Patent number: 6768889
    Abstract: An image is formed on an image display medium having a display layer whose optical characteristics are changed by applying an electric field. An electrostatic latent image corresponding to the image to be formed is formed on a dielectric film having a plurality of float electrodes formed thereon by injecting an electrical charge into at least one of the float electrodes. The electric field formed by the electrostatic latent image on the dielectric film is applied to the display layer of the image display medium by bringing the electrostatic latent image formed on the dielectric film to a position opposed to the image display medium.
    Type: Grant
    Filed: January 22, 2003
    Date of Patent: July 27, 2004
    Assignee: Minolta Co., Ltd.
    Inventor: Akihito Ikegawa
  • Patent number: 6686940
    Abstract: A reversible image display medium accommodates a dry developer in each cell formed between two substrates. The developer contains at least two kinds of frictionally chargeable dry developing particles having different chargeable polarities and different optical reflection densities. An image display can be achieved by forming an electrostatic latent image on one of the substrates to drive the developing particles in an electric field based on the electrostatic latent image. The developing particles are set to an average charge quantity of 1.0 &mgr;C/g to 10 &mgr;C/g to achieve good image display. Optionally at least one kind of the developing particles are magnetic developing particles having a coercive force of 50 oersteds to 250 oersteds, and optionally having an optical reflection density of 1.0 or more. An amount of small-size developing particles and/or an addition of a third component may be adjusted and volume average particle size ratio of developing particles may be controlled.
    Type: Grant
    Filed: November 15, 2001
    Date of Patent: February 3, 2004
    Assignee: Minolta Co., Ltd.
    Inventors: Masahiko Matsuura, Hiroshi Mizuno, Akihito Ikegawa, Masaharu Kanazawa, Keyaki Yogome, Takaji Kurita
  • Publication number: 20030214567
    Abstract: The invention provides an image display medium comprising: a first transparent substrate disposed on an observation side; a second substrate disposed on a further side from the observation side than the first substrate; and a display layer formed between the first substrate and the second substrate and containing a plurality of developer particles; the first substrate including a color filter having at least one group of a plurality of light-transmitting filter films of different colors. The invention also provides an image recording apparatus including a recording head for recording an image on the medium and a positioning device for positioning the filter films of the color filter and the recording head. The invention further provides an image recording method comprising the steps of positioning the filter films of the medium and the recording head, and recording an image by the recording head on the medium having the filter films positioned.
    Type: Application
    Filed: April 4, 2003
    Publication date: November 20, 2003
    Inventors: Masaharu Kanazawa, Keyaki Yogome, Akihito Ikegawa
  • Publication number: 20030138266
    Abstract: An image is formed on an image display medium having a display layer whose optical characteristics are changed by applying an electric field. An electrostatic latent image corresponding to the image to be formed is formed on a dielectric film having a plurality of float electrodes formed thereon by injecting an electrical charge into at least one of the float electrodes. The electric field formed by the electrostatic latent image on the dielectric film is applied to the display layer of the image display medium by bringing the electrostatic latent image formed on the dielectric film to a position opposed to the image display medium.
    Type: Application
    Filed: January 22, 2003
    Publication date: July 24, 2003
    Inventor: Akihito Ikegawa
  • Publication number: 20030113144
    Abstract: Convexity-cleaning method and device for removing toner adhering to a convexity or convexities of an irregular surface of a non-fixing type image receiving sheet. When removing the toner, a contact surface of a cleaning member is brought into contact with the convexity or convexities, the irregular surface is moved relatively to the cleaning member at a first surface moving speed, the contact surface of the cleaning member is moved at a second surface moving speed, and a difference is made between the first and second surface moving speeds.
    Type: Application
    Filed: June 5, 2002
    Publication date: June 19, 2003
    Applicant: Minolta Co., Ltd.
    Inventors: Masaharu Kanazawa, Akira Izutani, Hiroshi Mizuno, Akihito Ikegawa, Keyaki Yogome
  • Publication number: 20030079986
    Abstract: In order to provide an image creating apparatus which is driven at a high speed by a low voltage and realizes high contrast, the image creating apparatus of the present invention applies a voltage selectively to surfaces of arranged plural polymeric electrolyte films and generate a potential difference between both surfaces of the polymeric electrolyte films to which the voltage is applied to deform the polymeric electrolyte films. This image creating apparatus can provide an optical shutter of an image recording apparatus and a reflection or transmitting type image display device.
    Type: Application
    Filed: October 22, 2002
    Publication date: May 1, 2003
    Applicant: Minolta Co., Ltd.
    Inventor: Akihito Ikegawa
  • Publication number: 20020185788
    Abstract: An initial resin substrate is formed by laminating resin layers, and one surface of the initial substrate is heated and pressed by a molding die to mold a projected and dented surface such that substantially no deformation occurs on the resin layer providing a surface opposed to the one surface of the initial substrate. A reversible image display medium is produced by a method comprising the steps of accommodating a dry developer into the concavities and fixing a second substrate to the first substrate using an adhesive. Alternatively a reversible image display medium may be produced by, e.g.
    Type: Application
    Filed: March 29, 2002
    Publication date: December 12, 2002
    Inventors: Kenji Otokawa, Denji Nota, Akihito Ikegawa, Keyaki Yogome, Takaji Kurita
  • Publication number: 20020097199
    Abstract: This invention relates to a method or apparatus capable of displaying a high-quality image using a reversible image display medium which can be repeatedly used and in which a cell(s) formed between two substrates accommodates at least two kinds of frictionally chargeable dry developing particles having different chargeable polarities and different optical reflection densities; an electric field is applied to the developing particles for performing image display; in image display, the electric field strength of, e.g., 0.3 V/&mgr;m to 3.0 V/&mgr;m is applied to the developer; an oscillating force (e.g.
    Type: Application
    Filed: November 16, 2001
    Publication date: July 25, 2002
    Applicant: Minolta Co. Ltd.
    Inventors: Masahiko Matsuura, Hiroshi Mizuno, Akihito Ikegawa, Masaharu Kanazawa, Keyaki Yogome, Takaji Kurita
  • Publication number: 20020097198
    Abstract: The invention provides a reversible image display medium accommodating a dry developer in each cell formed between two substrates. The developer contains at least two kinds of frictionally chargeable dry developing particles having different chargeable polarities and different optical reflection densities. An image display can be achieved by forming an electrostatic latent image on one of the substrates to drive the developing particles in an electric field based on the electrostatic latent image. The developing particles are set to an average charge quantity of 1.0 &mgr;C/g to 10 &mgr;C/g to achieve good image display. Optionally at least one kind of the developing particles are magnetic developing particles having a coercive force of 50 oersteds to 250 oersteds, and optionally having an optical reflection density of 1.0 or more.
    Type: Application
    Filed: November 15, 2001
    Publication date: July 25, 2002
    Applicant: Minolta Co., Ltd.
    Inventors: Masahiko Matsuura, Hiroshi Mizuno, Akihito Ikegawa, Masaharu Kanazawa, Keyaki Yogome, Takaji Kurita
  • Publication number: 20020089495
    Abstract: Disclosed is a reversible image display medium which can be repeatedly used and can display high quality images, in which cells between the two substrates accommodate a dry developer containing at least two kinds of frictionally chargeable dry developing particles having different chargeable polarities and different optical reflection densities; images are displayed by forming an electrostatic latent image corresponding to the image to be formed on one of the two substrates to drive the developing particles in an electrostatic field based on the electrostatic latent image; a developer-facing surface of one of the substrates has a surface resistivity of at least 1×1012 ohm/square; a developer-facing surface of the opposite substrate has a surface resistivity from 1×106 ohm/square to 1×1012 ohm/square; a developer-facing surface of one of the substrates has a surface average median roughness Ra of 0.2 &mgr;m to 0.
    Type: Application
    Filed: November 16, 2001
    Publication date: July 11, 2002
    Applicant: Minolta Co., Ltd.
    Inventors: Masahiko Matsuura, Hiroshi Mizuno, Akihito Ikegawa, Masaharu Kanazawa, Keyaki Yogome, Takaji Kurita
  • Patent number: 6115573
    Abstract: An image forming apparatus includes an image carrying member having an electrostatic latent image carried on its surface, a release agent application device for applying a release agent to the surface of the image carrying member, an ink developing device for bringing an ink into contact with the image carrying member having the electrostatic latent image formed thereon and the release agent applied thereto, to form an ink image corresponding to the electrostatic latent image, and an ink supplying device for supplying a replenishing ink to the ink developing device when the release agent is mixed with the ink in the ink developing device to control the viscosity of the ink, wherein the replenishing ink differs in viscosity from the ink in the ink developing device. And, the supply of ink is varied as a function of the environmental conditions, such as temperature. Image forming methods are disclosed for using the disclosed image forming apparatuses.
    Type: Grant
    Filed: October 26, 1998
    Date of Patent: September 5, 2000
    Assignee: Minolta Co., Ltd.
    Inventors: Tomoo Izumi, Hiroyuki Yamasaki, Satoshi Deishi, Takashi Kondo, Katsuhiko Takeda, Akihito Ikegawa