Patents by Inventor Hidefumi Nagashima

Hidefumi Nagashima 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: 20140192121
    Abstract: An inkjet recording method includes forming an image on a coated layer provided at least one side of the substrate of a recording medium with ink containing a colorant; and then applying a post-processing fluid comprising a resin to the image; wherein the application amount per unit area of the post-processing fluid to the image is controlled to be less than the application amount per unit area of the ink to form the image.
    Type: Application
    Filed: January 10, 2014
    Publication date: July 10, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventors: Akiko Bannai, Hidefumi NAGASHIMA, Mariko KOJIMA, Michihiko NAMBA
  • Patent number: 8382271
    Abstract: The present invention provides an inkjet ink which is excellent in image quality and high-speed printing on plain paper, in storage stability and in ejection stability and gives less load on a maintenance device for an inkjet recording apparatus; and an ink cartridge, an inkjet recording apparatus, and an inkjet recording method, using the inkjet ink. An inkjet ink containing a water dispersion of pigment-containing water-insoluble vinyl polymer particles; a water-soluble organic solvent; and water, wherein an ink residue from the inkjet ink has a viscosity of 3,000 mPa·s or less, the ink residue is obtained by leaving the inkjet ink to stand at a temperature of 25° C. and a humidity of 15% until substantially no mass change occurs, and wherein the inkjet ink, pH of which is adjusted to 7 with an acid, has a viscosity of 500 mPa·s or more.
    Type: Grant
    Filed: September 2, 2009
    Date of Patent: February 26, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Goto, Yukitaka Watarai, Koji Katsuragi, Hidefumi Nagashima
  • Publication number: 20130002776
    Abstract: A inkjet recording medium and ink set including ink containing water, a hydrosoluble organic solvent comprising an amide compound represented by the following Chemical Structure 1, a surface active agent; and a coloring agent, and a recording medium containing a substrate; and a coated layer on at least one side of the substrate, wherein the transfer amount of pure water to the recording medium having the coated layer is 2 ml/m2 to 35 ml/m2 during a contact time of 100 ms and 3 ml/m2 to 40 ml/m2 during a contact time of 400 ms when measured by a liquid dynamic absorption tester at 23° C.
    Type: Application
    Filed: June 12, 2012
    Publication date: January 3, 2013
    Applicant: RICOH COMPANY, LTD.
    Inventors: Hidefumi NAGASHIMA, Hiroshi GOTOU
  • Patent number: 8304043
    Abstract: There is provided an inkjet recording ink and recording media set, which contains: an inkjet recording ink; and a recording medium, wherein the inkjet recording ink comprises at least: water; a water-soluble organic solvent; and a colorant containing carbon black, and having a volume average particle diameter of 40 nm to 100 nm, wherein the recording medium contains: a substrate; and a coating layer on at least one side of the substrate, and wherein an amount of pure water transferred to the recording medium, as measured with a dynamic scanning absorptometer at 23 C and 50% RH, at a contact time of 100 ms is 2 ml/m2 to 35 ml/m2 while an amount of pure water transferred to the recording medium at a contact time of 400 ms is 3 ml/m2 to 40 ml/m2.
    Type: Grant
    Filed: March 14, 2008
    Date of Patent: November 6, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Hidefumi Nagashima, Kiyofumi Nagai, Michihiko Namba, Mariko Kojima
  • Patent number: 8110257
    Abstract: An ink-jet recording method including recording onto a recording medium a black image of composite black using a black ink and color inks, wherein the black ink includes water, a water-soluble organic solvent, a surfactant, and a carbon black whose volume average particle diameter is 40 nm to 100 nm, and the color inks include a cyan ink, a magenta ink and a yellow ink, wherein the mass ratio (A/B) of a solid content A to a water-soluble organic solvent content B in the black ink is in the range of 1/8 to 1/15, and wherein the recording medium includes a support with a coating layer, and the amounts of purified water transferred to the recording medium at contact periods of 100 ms and 400 ms at a temperature of 23 C and a relative humidity of 50% are 2 ml/m2 to 35 ml/m2 and 3 ml/m2 to 40 ml/m2 respectively.
    Type: Grant
    Filed: June 26, 2008
    Date of Patent: February 7, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Hidefumi Nagashima, Kiyofumi Nagai
  • Publication number: 20110164086
    Abstract: The present invention provides an inkjet ink which is excellent in image quality and high-speed printing on plain paper, in storage stability and in ejection stability and gives less load on a maintenance device for an inkjet recording apparatus; and an ink cartridge, an inkjet recording apparatus, and an inkjet recording method, using the inkjet ink. An inkjet ink containing a water dispersion of pigment-containing water-insoluble vinyl polymer particles; a water-soluble organic solvent; and water, wherein an ink residue from the inkjet ink has a viscosity of 3,000 mPa·s or less, the ink residue is obtained by leaving the inkjet ink to stand at a temperature of 25° C. and a humidity of 15% until substantially no mass change occurs, and wherein the inkjet ink, pH of which is adjusted to 7 with an acid, has a viscosity of 500 mPa·s or more.
    Type: Application
    Filed: September 2, 2009
    Publication date: July 7, 2011
    Inventors: Hiroshi Ggoto, Yukitaka Watarai, Koji Katsuragi, Hidefumi Nagashima
  • Publication number: 20100196673
    Abstract: An ink-jet recording method including recording onto a recording medium a black image of composite black using a black ink and color inks, wherein the black ink includes water, a water-soluble organic solvent, a surfactant, and a carbon black whose volume average particle diameter is 40 nm to 100 nm, and the color inks include a cyan ink, a magenta ink and a yellow ink, wherein the mass ratio (A/B) of a solid content A to a water-soluble organic solvent content B in the black ink is in the range of 1/8 to 1/15, and wherein the recording medium includes a support with a coating layer, and the amounts of purified water transferred to the recording medium at contact periods of 100 ms and 400 ms at a temperature of 23 C and a relative humidity of 50% are 2 ml/m2 to 35 ml/m2 and 3 ml/m2 to 40 ml/m2 respectively.
    Type: Application
    Filed: June 26, 2008
    Publication date: August 5, 2010
    Inventors: Hidefumi Nagashima, Kiyofumi Nagai
  • Publication number: 20090258196
    Abstract: There is provided an inkjet recording ink and recording media set, which contains: an inkjet recording ink; and a recording medium, wherein the inkjet recording ink comprises at least: water; a water-soluble organic solvent; and a colorant containing carbon black, and having a volume average particle diameter of 40 nm to 100 nm, wherein the recording medium contains: a substrate; and a coating layer on at least one side of the substrate, and wherein an amount of pure water transferred to the recording medium, as measured with a dynamic scanning absorptometer at 23 C and 50% RH, at a contact time of 100 ms is 2 ml/m2 to 35 ml/m2 while an amount of pure water transferred to the recording medium at a contact time of 400 ms is 3 ml/m2 to 40 ml/m2.
    Type: Application
    Filed: March 14, 2008
    Publication date: October 15, 2009
    Inventors: Hidefumi Nagashima, Kiyofumi Nagai, Michihiko Namba, Mariko Kojima