Patents by Inventor Keitaro Nakano

Keitaro Nakano 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: 11027544
    Abstract: An ink jet method includes: a discharging step of discharging a radiation-curable ink jet composition onto a recording medium at an ink weight per dot of 22 ng/dot or less by using an ink jet head configured to discharge the radiation-curable ink jet composition and having a nozzle density of 600 npi or more; and an irradiating step of irradiating, with radiation, the radiation-curable ink jet composition attached to the recording medium. The radiation-curable ink jet composition contains polymerizable compounds including a monofunctional monomer and a multifunctional monomer. The monofunctional monomer includes a nitrogen-containing monofunctional monomer. The amount of the monofunctional monomer is 90 mass % or more relative to the total amount of the polymerizable compounds. The amount of the nitrogen-containing monofunctional monomer is from 1 to 15 mass % relative to the total amount of the polymerizable compounds.
    Type: Grant
    Filed: February 7, 2020
    Date of Patent: June 8, 2021
    Inventors: Keitaro Nakano, Kyohei Tanaka, Midori Sekine, Chigusa Sato
  • Publication number: 20210094321
    Abstract: Provided is an ink jet recording method including: discharging first ultraviolet curable ink of a radical polymerization reaction type which contains a radical photopolymerization initiator and a radical polymerization compound and in which transmittance at a wavelength of 395 nm is equal to or less than 1%, onto a recording medium; and curing the first ultraviolet curable ink which is landed on the recording medium by irradiating the ink with ultraviolet light, in which a light source which initially emits the ultraviolet light in the curing of the ink is an ultraviolet light emitting diode in which peak intensity of the irradiated ultraviolet light is equal to or more than 800 mW/cm2.
    Type: Application
    Filed: December 14, 2020
    Publication date: April 1, 2021
    Inventors: Mikito NAKAJIMA, Keitaro Nakano, Mitsuaki Yoshizawa
  • Patent number: 10953657
    Abstract: An ink jet printing apparatus includes a radiation-curable ink having a surface tension of 25.0 mN/m or less, and a printing head including a nozzle face having an opening of a nozzle through which the radiation-curable ink is ejected, and a liquid-repellent film on the nozzle face. The liquid-repellent film enables the radiation-curable ink to forms a contact angle of 60.0 degrees or more therewith.
    Type: Grant
    Filed: November 15, 2019
    Date of Patent: March 23, 2021
    Inventors: Midori Sekine, Tomohiro Numajiri, Keitaro Nakano
  • Publication number: 20210071024
    Abstract: An ink set of radiation curable ink jet inks each of which contains polymerizable compounds, includes a color ink and a clear ink, the polymerizable compounds contained in the clear ink include a monomer A having a hydroxy group and a monomer B having a volume of 0.26 nm3 or more and a height direction area of 0.25 nm2 or more with respect to a long side each of which is defined by the Van der Waals radii, and a total content of the monomer A and the monomer B is 80 percent by mass or more with respect to a total mass of the polymerizable compounds contained in the clear ink.
    Type: Application
    Filed: September 4, 2020
    Publication date: March 11, 2021
    Inventors: Kyohei TANAKA, Keitaro NAKANO, Midori SEKINE, Yuko HISHIDA
  • Patent number: 10934444
    Abstract: A radiation-curable ink jet composition includes monomers, the monomers including 86% by mass or more of one or more monofunctional monomers relative to all the monomers, where a glass transition temperature of the radiation-curable ink jet composition calculated from glass transition temperatures of all the monomers is 42° C. or higher.
    Type: Grant
    Filed: September 25, 2019
    Date of Patent: March 2, 2021
    Inventors: Kyohei Tanaka, Keitaro Nakano, Midori Sekine
  • Publication number: 20210047592
    Abstract: There is provided a maintenance liquid, which is used in maintenance of a device equipped with a discharge head for discharging an ultraviolet ray curable-type composition containing the acyl phosphine oxide-based photopolymerization initiator toward an attachment object, including a polymerizable compound in which a saturation solubility of an acyl phosphine oxide-based photopolymerization initiator at 20° C. is equal to or greater than 5.0% by mass.
    Type: Application
    Filed: November 3, 2020
    Publication date: February 18, 2021
    Inventors: Keitaro Nakano, Chigusa Sato, Mitsuaki Yoshizawa
  • Publication number: 20210024761
    Abstract: Provided is an ink set of radiation-curable ink jet compositions each including a polymerizable compound component. The ink set includes a color ink and a clear ink as the radiation-curable ink jet compositions. The polymerizable compound component contained in the clear ink includes a monomer A having a volume of 260 angstrom3 or more and an area of 25 angstrom2 or more in the height direction with respect to a long side defined by a van-der-Waals radius, and the content of the monomer A contained in the clear ink is 80 mass % or more based on the total amount of the polymerizable compound component.
    Type: Application
    Filed: July 24, 2020
    Publication date: January 28, 2021
    Inventors: Kyohei TANAKA, Midori SEKINE, Keitaro NAKANO, Yuko HISHIDA, Tsuyoshi SANO
  • Patent number: 10894430
    Abstract: Provided is an ink jet recording method including: discharging first ultraviolet curable ink of a radical polymerization reaction type which contains a radical photopolymerization initiator and a radical polymerization compound and in which transmittance at a wavelength of 395 nm is equal to or less than 1%, onto a recording medium; and curing the first ultraviolet curable ink which is landed on the recording medium by irradiating the ink with ultraviolet light, in which a light source which initially emits the ultraviolet light in the curing of the ink is an ultraviolet light emitting diode in which peak intensity of the irradiated ultraviolet light is equal to or more than 800 mW/cm2.
    Type: Grant
    Filed: January 6, 2020
    Date of Patent: January 19, 2021
    Assignee: Seiko Epson Corporation
    Inventors: Mikito Nakajima, Keitaro Nakano, Mitsuaki Yoshizawa
  • Publication number: 20210002499
    Abstract: A radiation curing ink jet printing method for forming a cured coating having a thickness of 0.5 ?m to 5 ?m includes an ejection step of ejecting a radiation-curable ink composition onto a printing medium, and an irradiation step of irradiating the radiation-curable ink composition on the printing medium with an active radiation having an emission peak wavelength in the range of 350 nm to 420 nm from an active radiation source. The radiation-curable ink composition contains one or more monofunctional monomers and one or more multifunctional monomers in such a proportion that the ratio of the total mass of the monofunctional monomers to the total mass of the multifunctional monomers is 0.45 or more. In the irradiation step, the radiation-curable ink composition is irradiated with the active radiation in an atmosphere having an oxygen concentration lower than the atmospheric oxygen concentration.
    Type: Application
    Filed: July 2, 2020
    Publication date: January 7, 2021
    Inventors: Chigusa SATO, Toru SAITO, Keitaro NAKANO
  • Publication number: 20200392353
    Abstract: A radiation-curable ink jet composition that is a white ink containing a white coloring material or a pale or clear ink containing 1.2% by mass or less of a coloring material contains at least one polymerizable compound including at least one of a monofunctional monomer having a nitrogen-containing heterocyclic structure and a monomer having a hydroxy group. In the composition, the thioxanthone-based photopolymerization initiator content is limited to 0.3% or less relative to the total mass of the radiation-curable ink jet composition.
    Type: Application
    Filed: June 16, 2020
    Publication date: December 17, 2020
    Inventors: Kyohei TANAKA, Keitaro NAKANO, Midori SEKINE
  • Publication number: 20200392357
    Abstract: A radiation-curable ink jet composition includes a polymerizable compound component including a monofunctional monomer component and a multifunctional monomer component, a photopolymerization initiator, and titanium oxide as a white color material. The content of the monofunctional monomer component is 90 mass % or more based on the total amount of the polymerizable compound component, and the weighted average of the glass transition temperatures of homopolymers of the respective polymerizable compounds is 48° C. or more when the mass ratios of the contents of the respective polymerizable compounds are weighted.
    Type: Application
    Filed: June 16, 2020
    Publication date: December 17, 2020
    Inventors: Midori SEKINE, Kyohei TANAKA, Keitaro NAKANO
  • Patent number: 10858614
    Abstract: There is provided a maintenance liquid, which is used in maintenance of a device equipped with a discharge head for discharging an ultraviolet ray curable-type composition containing the acyl phosphine oxide-based photopolymerization initiator toward an attachment object, including a polymerizable compound in which a saturation solubility of an acyl phosphine oxide-based photopolymerization initiator at 20° C. is equal to or greater than 5.0% by mass.
    Type: Grant
    Filed: June 11, 2019
    Date of Patent: December 8, 2020
    Assignee: Seiko Epson Corporation
    Inventors: Keitaro Nakano, Chigusa Sato, Mitsuaki Yoshizawa
  • Publication number: 20200369047
    Abstract: A photo-curable ink jet ink set includes an undercoating photo-curable ink jet ink containing a (meth)acrylic acid ester having a vinyl ether group expressed by general formula (I), and an overcoating photo-curable ink jet ink. The undercoating photo-curable ink jet ink has a higher surface tension than the overcoating photo-curable ink jet ink.
    Type: Application
    Filed: August 14, 2020
    Publication date: November 26, 2020
    Inventors: Keitaro NAKANO, Jun ITO
  • Patent number: 10780707
    Abstract: A pigment dispersion containing a metal pigment, wherein the metal pigment contains plate-like particles, and in the case where the longitudinal diameter on the planar surface of the plate-like particle is X, the lateral diameter is Y, and the thickness is Z, the 50% average particle diameter R50 of a corresponding circle determined from the surface area in the X-Y plane of the plate-like particle is between 0.5 and 3 ?m, and the condition R50/Z>5 is satisfied.
    Type: Grant
    Filed: October 18, 2019
    Date of Patent: September 22, 2020
    Assignee: Seiko Epson Corporation
    Inventors: Takashi Oyanagi, Keitaro Nakano
  • Patent number: 10780717
    Abstract: A photo-curable ink jet ink set includes an undercoating photo-curable ink jet ink containing a (meth)acrylic acid ester having a vinyl ether group expressed by general formula (I), and an overcoating photo-curable ink jet ink. The undercoating photo-curable ink jet ink has a higher surface tension than the overcoating photo-curable ink jet ink.
    Type: Grant
    Filed: February 21, 2019
    Date of Patent: September 22, 2020
    Assignee: Seiko Epson Corporation
    Inventors: Keitaro Nakano, Jun Ito
  • Publication number: 20200255679
    Abstract: A radiation-curable ink jet composition comprises a polymerizable compound component including a monofunctional monomer component and a multifunctional monomer component. The content of the monofunctional monomer component is 87 mass % or more based on the polymerizable compound. The monofunctional monomer component includes a nitrogen-containing monofunctional monomer component, and the content of the nitrogen-containing monofunctional monomer component is 14 mass % or less based on total amount of the radiation-curable ink jet composition. The weighted average of the glass transition temperatures of homopolymers of the respective polymerizable compounds is 42° C. or more when the mass ratios of the contents of the respective polymerizable compounds are weighted.
    Type: Application
    Filed: February 7, 2020
    Publication date: August 13, 2020
    Inventors: Midori SEKINE, Kyohei TANAKA, Keitaro NAKANO
  • Publication number: 20200254784
    Abstract: An ink jet method includes: a discharging step of discharging a radiation-curable ink jet composition onto a recording medium at an ink weight per dot of 22 ng/dot or less by using an ink jet head having a nozzle density of 600 npi or more and configured to discharge the radiation-curable ink jet composition; and an irradiating step of irradiating, with radiation, the radiation-curable ink jet composition attached to the recording medium. The radiation-curable ink jet composition contains polymerizable compounds containing a monofunctional monomer and a multifunctional monomer. The monofunctional monomer includes a nitrogen-containing monofunctional monomer. The amount of the monofunctional monomer is 90 mass % or more relative to the total amount of the polymerizable compound. The amount of the nitrogen-containing monofunctional monomer is from 1 to 15 mass % relative to the total amount of the polymerizable compounds.
    Type: Application
    Filed: February 7, 2020
    Publication date: August 13, 2020
    Inventors: Chigusa SATO, Midori SEKINE, Kyohei TANAKA, Keitaro NAKANO
  • Publication number: 20200254756
    Abstract: An ink jet method includes an ejecting step of ejecting a radiation-curable ink jet composition from an ink jet head and an irradiating step of irradiating the ejected radiation-curable ink jet composition with an ultraviolet ray at an irradiation intensity of 3 to 10 W/cm2 by using a light emitting diode. The radiation-curable ink jet composition contains monofunctional monomers including a nitrogen-containing monofunctional monomer. The amount of the nitrogen-containing monofunctional monomer relative to the total amount of the radiation-curable ink jet composition is 5 to 40 mass %.
    Type: Application
    Filed: February 7, 2020
    Publication date: August 13, 2020
    Inventors: Keitaro NAKANO, Kyohei TANAKA, Midori SEKINE, Chigusa SATO
  • Publication number: 20200254755
    Abstract: An ink jet method includes: a discharging step of discharging a radiation-curable ink jet composition onto a recording medium at an ink weight per dot of 22 ng/dot or less by using an ink jet head configured to discharge the radiation-curable ink jet composition and having a nozzle density of 600 npi or more; and an irradiating step of irradiating, with radiation, the radiation-curable ink jet composition attached to the recording medium. The radiation-curable ink jet composition contains polymerizable compounds including a monofunctional monomer and a multifunctional monomer. The monofunctional monomer includes a nitrogen-containing monofunctional monomer. The amount of the monofunctional monomer is 90 mass % or more relative to the total amount of the polymerizable compounds. The amount of the nitrogen-containing monofunctional monomer is from 1 to 15 mass % relative to the total amount of the polymerizable compounds.
    Type: Application
    Filed: February 7, 2020
    Publication date: August 13, 2020
    Inventors: Keitaro NAKANO, Kyohei TANAKA, Midori SEKINE, Chigusa SATO
  • Publication number: 20200255678
    Abstract: A radiation-curable ink jet composition comprises a polymerizable compound component including a monofunctional monomer component and a multifunctional monomer component. The content of the monofunctional monomer component is 87 mass % or more based on the total amount of the polymerizable compound component, the monofunctional monomer component includes a monofunctional acrylate containing a polycyclic hydrocarbon group, and the weighted average of the glass transition temperatures of homopolymers of the respective polymerizable compounds is 42° C. or more when the mass ratios of the contents of the respective polymerizable compounds are weighted.
    Type: Application
    Filed: February 7, 2020
    Publication date: August 13, 2020
    Inventors: Midori SEKINE, Kyohei TANAKA, Keitaro NAKANO