Patents by Inventor Yukitaka Watarai

Yukitaka Watarai 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: 11560491
    Abstract: A liquid composition includes an inorganic particle and a multivalent metal salt, wherein the liquid composition has a tacking force of 50 mN or less in an area of cast-coated paper where the liquid composition is applied in an amount of 0.12 mg/cm2 for the cast-coated paper followed by heating at 80 degrees C. for 15 seconds.
    Type: Grant
    Filed: January 28, 2019
    Date of Patent: January 24, 2023
    Assignee: Ricoh Company, Ltd.
    Inventors: Dongsik Jang, Yukitaka Watarai, Tsutomu Maekawa, Takashi Tamai, Atsufumi Hanazawa, Koji Katsuragi
  • Patent number: 11040561
    Abstract: An ink and processing liquid set contains a processing liquid to be applied to a recording medium, the processing liquid including a multivalent metal salt and an ink to be applied to an area of the recording medium where the processing liquid has been applied, the ink including a urethane resin, a styrene-acrylic resin, and a pigment, wherein the following relations are satisfied: 0.5?B/C?0.7, where B represents a static surface tension of the ink and C represents a static surface tension of the processing liquid; and 0.5?E/D?0.9, and 35 (mN/m)?E?55 (mN/m), where D represents a dynamic surface tension at 15 ms of the processing liquid and E represents a dynamic surface tension at 1500 ms of the processing liquid.
    Type: Grant
    Filed: March 13, 2019
    Date of Patent: June 22, 2021
    Assignee: Ricoh Company, Ltd.
    Inventors: Takashi Tamai, Dongsik Jang, Atsufumi Hanazawa, Satoshi Takahashi, Yoshiki Yanagawa, Tsutomu Maekawa, Yukitaka Watarai
  • Publication number: 20200399495
    Abstract: A liquid composition includes an inorganic particle and a multivalent metal salt, wherein the liquid composition has a tacking force of 50 mN or less in an area of cast-coated paper where the liquid composition is applied in an amount of 0.12 mg/cm2 for the cast-coated paper followed by heating at 80 degrees C. for 15 seconds.
    Type: Application
    Filed: January 28, 2019
    Publication date: December 24, 2020
    Inventors: Dongsik JANG, Yukitaka WATARAI, Tsutomu MAEKAWA, Takashi TAMAI, Atsufumi HANAZAWA, Koji KATSURAGI
  • Patent number: 10647129
    Abstract: A printing method includes applying a processing fluid to a recording medium and applying an ink to the recording medium, wherein the processing fluid contains a first nonionic resin including the following structure unit a-1, the first nonionic resin having a glass transition temperature of 15 degrees C.
    Type: Grant
    Filed: March 7, 2018
    Date of Patent: May 12, 2020
    Assignee: Ricoh Company, Ltd.
    Inventors: Atsufumi Hanazawa, Hiroshi Gotou, Tsutomu Maekawa, Yukitaka Watarai, Koji Katsuragi, Tomohiro Nakagawa
  • Publication number: 20190283479
    Abstract: An ink and processing liquid set contains a processing liquid to be applied to a recording medium, the processing liquid comprising a multivalent metal salt and an ink to be applied to an area of the recording medium where the processing liquid has been applied, the ink comprising a urethane resin, a styrene-acrylic resin, and a pigment, wherein the following relations are satisfied: 0.5?B/C?0.7, where B represents a static surface tension of the ink and C represents a static surface tension of the processing liquid; and 0.5?E/D?0.9, and 35 (mN/m)?E?55 (mN/m), where D represents a dynamic surface tension at 15 ms of the processing liquid and E represents a dynamic surface tension at 1500 ms of the processing liquid.
    Type: Application
    Filed: March 13, 2019
    Publication date: September 19, 2019
    Inventors: Takashi TAMAI, Dongsik Jang, Atsufumi Hanazawa, Satoshi Takahashi, Yoshiki Yanagawa, Tsutomu Maekawa, Yukitaka Watarai
  • Publication number: 20180265728
    Abstract: A printing method includes applying a processing fluid to a recording medium and applying an ink to the recording medium, wherein the processing fluid contains a first nonionic resin including the following structure unit a-1, the first nonionic resin having a glass transition temperature of 15 degrees C.
    Type: Application
    Filed: March 7, 2018
    Publication date: September 20, 2018
    Inventors: Atsufumi Hanazawa, Hiroshi Gotou, Tsutomu Maekawa, Yukitaka Watarai, Koji Katsuragi, Tomohiro Nakagawa
  • Patent number: 9120334
    Abstract: Provided is an image forming apparatus, including: a pretreatment unit configured to bring a surface of a recording medium into contact with plasma; and an image forming unit configured to eject an ink onto the recording medium to thereby form an image; wherein the ink contains a pigment, water, a water-soluble organic solvent, and resin particles, wherein the water-soluble organic solvent is an amide compound having an inorganic/organic value (I/O value) of 1.1 to 2.0, and wherein the resin particles are ether-based polyurethane resin particles and have an acid group amount of 2.0 meq/g or more.
    Type: Grant
    Filed: January 14, 2015
    Date of Patent: September 1, 2015
    Assignee: RICOH COMPANY, LTD.
    Inventors: Koji Nagai, Yukitaka Watarai
  • Publication number: 20150202897
    Abstract: Provided is an image forming apparatus, including: a pretreatment unit configured to bring a surface of a recording medium into contact with plasma; and an image forming unit configured to eject an ink onto the recording medium to thereby form an image; wherein the ink contains a pigment, water, a water-soluble organic solvent, and resin particles, wherein the water-soluble organic solvent is an amide compound having an inorganic/organic value (I/O value) of 1.1 to 2.0, and wherein the resin particles are ether-based polyurethane resin particles and have an acid group amount of 2.0 meq/g or more.
    Type: Application
    Filed: January 14, 2015
    Publication date: July 23, 2015
    Applicant: Ricoh Company, Ltd.
    Inventors: Koji Nagai, Yukitaka Watarai
  • 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
  • Patent number: 8187372
    Abstract: An ink-jet O/W emulsion ink of the present invention includes an aqueous continuous phase (a), and a nonaqueous discontinuous phase (b), wherein the aqueous continuous phase (a) includes water, at least one pigment and at least one ionic or nonionic surfactant, and the nonaqueous discontinuous phase (b) includes at least one water-insoluble organic material having a hydroxyl group.
    Type: Grant
    Filed: November 11, 2008
    Date of Patent: May 29, 2012
    Assignee: Ricoh Company, Ltd.
    Inventor: Yukitaka Watarai
  • Patent number: 8136916
    Abstract: An image-forming apparatus includes a head unit configured to include line-type recording heads for ejecting ink droplets, a transport mechanism disposed facing the recording head and configured to transport a sheet, a maintain-recovery mechanism disposed downstream from the transport mechanism in a direction in which the sheet is transported and configured to maintain and recover the line type recording heads, and a head drive mechanism configured to move the head unit between a position facing the transport mechanism and a position facing the maintain-recovery mechanism in the direction in which the sheet is transported.
    Type: Grant
    Filed: January 15, 2009
    Date of Patent: March 20, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Yusuke Nemoto, Yoshihiko Kudoh, Akira Saito, Yoshiyuki Shishido, Yukitaka Watarai, Hiroyuki Hiratsuka, Susumu Shirauchi, Shin-ichi Shoji
  • 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: 20090179928
    Abstract: An image-forming apparatus includes a head unit configured to include line-type recording heads for ejecting ink droplets, a transport mechanism disposed facing the recording head and configured to transport a sheet, a maintain-recovery mechanism disposed downstream from the transport mechanism in a direction in which the sheet is transported and configured to maintain and recover the line type recording heads, and a head drive mechanism configured to move the head unit between a position facing the transport mechanism and a position facing the maintain-recovery mechanism in the direction in which the sheet is transported.
    Type: Application
    Filed: January 15, 2009
    Publication date: July 16, 2009
    Applicant: RICOH COMPANY, LTD.
    Inventors: Yusuke NEMOTO, Yoshihiko Kudoh, Akira Saito, Yoshiyuki Shishido, Yukitaka Watarai, Hiroyuki Hiratsuka, Susumu Shirauchi, Shin-ichi Shoji
  • Publication number: 20090136669
    Abstract: An ink-jet O/W emulsion ink of the present invention includes an aqueous continuous phase (a), and a nonaqueous discontinuous phase (b), wherein the aqueous continuous phase (a) includes water, at least one pigment and at least one ionic or nonionic surfactant, and the nonaqueous discontinuous phase (b) includes at least one water-insoluble organic material having a hydroxyl group.
    Type: Application
    Filed: November 11, 2008
    Publication date: May 28, 2009
    Inventor: Yukitaka WATARAI
  • Patent number: 6149720
    Abstract: A water-in-oil type emulsion ink composed of 10-90% by weight of an oil phase and 90-10% by weight of an aqueous phase. The oil phase contains a petroleum solvent having a kinematic viscosity of greater than 6-10 mm.sup.2 /s at 40.degree. C. and such a carbon content distribution that a naphthenic carbon content C.sub.N is at least 34%, an aromatic carbon content C.sub.A is 2-20% and a paraffinic carbon content CP is less than 55%.
    Type: Grant
    Filed: February 17, 2000
    Date of Patent: November 21, 2000
    Assignee: Tohoru Ricoh Co., Ltd.
    Inventors: Keisuke Asada, Yukitaka Watarai, Koji Ono, Yoshihiko Sato
  • Patent number: 5806718
    Abstract: An ink cartridge for use with, for example, a stencil printer and storing viscous ink therein is disclosed. The cartridge is free from damage and deformation during storage or transport in various kinds of atmospheres. Particularly, an ink outlet included in the cartridge is prevented from tilting. The cartridge can, therefore, be surely and accurately mounted to an apparatus. The ink outlet is protected from damage even when the cartridge is let fall by accident.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: September 15, 1998
    Assignee: Tohoku Ricoh Co., Ltd.
    Inventors: Yoshio Ota, Kouji Ono, Yukitaka Watarai