Patents by Inventor Chiyoko Tada

Chiyoko Tada 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: 20230002908
    Abstract: Disclosed is an electrical steel sheet with an insulating coating formed by applying a surface-treatment agent to at least one surface of the electrical steel sheet and drying the surface-treatment agent, wherein the surface-treatment agent contains: certain trialkoxysilane and/or dialkoxysilane (A); a silane coupling agent (B) that does not contain a polymerizable unsaturated group in its structure; plate-like silica (C); a polymerizable unsaturated-group-containing compound (D); and water, within a range satisfying the following conditions (1) to (3): (1) a mass ratio (A/B) of (A) to (B) is from 0.05 to 1.00; (2) a content of (C) is 2 mass % to 30 mass % with respect to a total mass of (A) to (D) in the surface-treatment agent; and (3) a content of (D) is 2 mass % to 18 mass % with respect to the total mass of (A) to (D) in the surface-treatment agent.
    Type: Application
    Filed: October 13, 2020
    Publication date: January 5, 2023
    Applicant: JFE STEEL CORPORATION
    Inventors: Nobuko NAKAGAWA, Chiyoko TADA, Naoki MURAMATSU
  • Publication number: 20220372600
    Abstract: A non-oriented electrical steel sheet produced by hot-rolling a steel slab containing Si: 2.8 to 6.5 mass % and Zn: 0.0005 to 0.0050 mass % followed by cold rolling and finish annealing, a coating agent containing at least one element from Sn, Sb, P, S, Se, As, Te, B, Pb, and Bi is applied to the surface after annealing forming an insulation coating with nitriding-suppressing ability. Alternatively, an intermediate layer containing at least one element from Sn, Sb, P, S, Se, As, Te, B, Pb, and Bi and having a nitriding-suppressing ability forms on the steel sheet iron matrix after the annealing and forms an insulation coating, without above elements, on the intermediate layer thus obtaining a non-oriented electrical steel sheet wherein a high strength rotor core with and stator core with excellent magnetic is simultaneously obtained, and a motor core including a stator core and rotor core from the steel sheet.
    Type: Application
    Filed: October 12, 2020
    Publication date: November 24, 2022
    Applicant: JFE STEEL CORPORATION
    Inventors: Yoshiaki ZAIZEN, Nobuko NAKAGAWA, Yoshihiko ODA, Tomoyuki OKUBO, Chiyoko TADA
  • Publication number: 20220194055
    Abstract: An electromagnetic steel sheet coated with an insulating film with excellent hardness and suitable for use as a material for iron cores of large-sized electric-power generators; and a process for producing the electromagnetic steel sheet coated with an insulating film. The purpose is achieved with a coating material for forming insulating films, the coating material including a solvent and components (A) to (C) contained therein in the respective amounts on a solid basis. (A) A water-compatible carboxylated resin; 100 parts by mass. (B) An aluminum-containing oxide; more than 40 parts by mass but less than 300 parts by mass per 100 parts by mass of the component (A). (C) At least one crosslinking agent selected from the group containing of melamine, isocyanates, and oxazoline; 100 parts by mass or more but less than 300 parts by mass per 100 parts by mass of the component (A).
    Type: Application
    Filed: March 15, 2022
    Publication date: June 23, 2022
    Applicant: JFE STEEL CORPORATION
    Inventors: Nobuko NAKAGAWA, Naoki MURAMATSU, Chiyoko TADA, Kengo NAKAMURA, Tomonori SUGISHITA
  • Publication number: 20220106689
    Abstract: An electrical steel sheet having excellent coating peel resistance that can be exhibited during a stamping process, so that sticking of the coating to a die is inhibited. The electrical steel sheet has an insulating coating disposed on at least one surface of the electrical steel sheet. The insulating coating (i) includes a composite comprising P and Al, (ii) has an aspect ratio in a range of 1 to 10, and (iii) has a thickness in a range of 500 nm to 2000 nm. The composite has a particle diameter in a range of 10 nm to 1000 nm.
    Type: Application
    Filed: September 26, 2019
    Publication date: April 7, 2022
    Applicant: JFE STEEL CORPORATION
    Inventors: Naoki MURAMATSU, Nobuko NAKAGAWA, Chiyoko TADA
  • Publication number: 20220028576
    Abstract: An electrical steel sheet provided with an insulating coating wherein the insulating coating is formed by a method includes forming an insulating coating on an electrical steel sheet, including: preparing a treatment solution that does not contain an Fe compound by adding an Si compound to water; applying the treatment solution to a surface of the electrical steel sheet; leaving the treatment solution on the surface of the electrical steel sheet to allow Fe in the electrical steel sheet to be dissolved in the treatment solution; and baking the treatment solution to form the insulating film such that a coating weight of Si in the insulating coating in terms of SiO2 is 50% to 99% of the total coating weight, and a ratio (Fe/Si) of content of Fe to content of Si in the insulating coating is 0.01 to 0.6 on a molar basis.
    Type: Application
    Filed: October 5, 2021
    Publication date: January 27, 2022
    Inventors: Kazumichi Sashi, Nobuko Nakagawa, Naoki Muramatsu, Chiyoko Tada, Nobue Fujibayashi
  • Patent number: 11186076
    Abstract: Provided is a method of manufacturing an electrical steel sheet with an adhesive insulating coating that has excellent high-temperature adhesive property and high-temperature oil resistance and, even after being stacked and subjected to stress relief annealing, has excellent magnetic properties (iron loss, magnetic flux density). The method comprises: applying a coating material to at least one side of an electrical steel sheet, the coating material containing (a) an aqueous epoxy resin, (b) a high-temperature hardening crosslinking agent in an amount of 30 parts by mass or less with respect to 100 parts by mass of the aqueous epoxy resin, in terms of solid content, (c) metal oxide particles, and (d) a solvent; and baking the coating material applied to the electrical steel sheet, under a condition of a peak steel sheet temperature of 150° C. or more and less than 230° C.
    Type: Grant
    Filed: December 11, 2017
    Date of Patent: November 30, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Nobuko Nakagawa, Naoki Muramatsu, Chiyoko Tada
  • Patent number: 11177052
    Abstract: A method for forming an insulating coating on an electrical steel sheet is provided. The method includes preparing a treatment solution by adding a Si compound to water and applying the treatment solution to a surface of the electrical steel sheet. Fe in the electrical steel sheet dissolves in the treatment solution and, thereafter, the electrical steel sheet and treatment solution are baked to form the insulating film. In the insulating film, a coating weight of Si in terms of SiO2 is 50% to 99% of the total coating weight, and a ratio (Fe/Si) of content of Fe to content of Si in the insulating coating is 0.01 to 0.6 on a molar basis.
    Type: Grant
    Filed: July 22, 2019
    Date of Patent: November 16, 2021
    Assignee: JFE Steel Corporation
    Inventors: Kazumichi Sashi, Nobuko Nakagawa, Naoki Muramatsu, Chiyoko Tada, Nobue Fujibayashi
  • Publication number: 20210324491
    Abstract: An electrical steel sheet with an insulating film having excellent chromium elution resistance, even in the case where the insulating film is baked by utilizing rapid heating, which improves productivity, and a method for manufacturing the steel sheet. The insulating film contains Fe, Cr, an organic resin, and an organic reducing agent on at least one surface of an electrical steel sheet. A ratio of the Fe content to the Cr content (Fe/Cr) is 0.010 to 0.6 in terms of molar ratio in the insulating film.
    Type: Application
    Filed: July 8, 2019
    Publication date: October 21, 2021
    Applicant: JFE STEEL CORPORATION
    Inventors: Chiyoko TADA, Nobuko NAKAGAWA, Takashi WADA, Shota TSUJI, Naoki MURAMATSU
  • Publication number: 20200086619
    Abstract: Provided is a method of manufacturing an electrical steel sheet with an adhesive insulating coating that has excellent high-temperature adhesive property and high-temperature oil resistance and, even after being stacked and subjected to stress relief annealing, has excellent magnetic properties (iron loss, magnetic flux density). The method comprises: applying a coating material to at least one side of an electrical steel sheet, the coating material containing (a) an aqueous epoxy resin, (b) a high-temperature hardening crosslinking agent in an amount of 30 parts by mass or less with respect to 100 parts by mass of the aqueous epoxy resin, in terms of solid content, (c) metal oxide particles, and (d) a solvent; and baking the coating material applied to the electrical steel sheet, under a condition of a peak steel sheet temperature of 150° C. or more and less than 230° C.
    Type: Application
    Filed: December 11, 2017
    Publication date: March 19, 2020
    Applicant: JFE STEEL CORPORATION
    Inventors: Nobuko NAKAGAWA, Naoki MURAMATSU, Chiyoko TADA
  • Patent number: 10526672
    Abstract: The disclosure provides an electrical steel sheet with an insulating coating excellent in both punchability and powdering resistance, without any chromium compound being contained in the insulating coating. The electrical steel sheet with an insulating coating includes an electrical steel sheet and an insulating coating formed on the electrical steel sheet. The insulating coating contains Si and particulate organic resin. The organic resin contains primary particles having an average primary particle size of 1.0 ?m or less, and 5% or more and 50% or less of the primary particles of the organic resin are agglomerated particles.
    Type: Grant
    Filed: April 5, 2016
    Date of Patent: January 7, 2020
    Assignee: JFE STEEL CORPORATION
    Inventors: Naoki Muramatsu, Nobuko Nakagawa, Kazumichi Sashi, Chiyoko Tada
  • Publication number: 20190348195
    Abstract: A method for forming an insulating coating on an electrical steel sheet is provided. The method includes preparing a treatment solution by adding a Si compound to water and applying the treatment solution to a surface of the electrical steel sheet. Fe in the electrical steel sheet dissolves in the treatment solution and, thereafter, the electrical steel sheet and treatment solution are baked to form the insulating film. In the insulating film, a coating weight of Si in terms of SiO2 is 50% to 99% of the total coating weight, and a ratio (Fe/Si) of content of Fe to content of Si in the insulating coating is 0.01 to 0.6 on a molar basis.
    Type: Application
    Filed: July 22, 2019
    Publication date: November 14, 2019
    Inventors: Kazumichi Sashi, Nobuko Nakagawa, Naoki Muramatsu, Chiyoko Tada, Nobue Fujibayashi
  • Patent number: 10403417
    Abstract: An electrical steel sheet is provided with insulating coating. The insulating coating contains Si and Fe. The coating weight of Si in the insulating coating in terms of SiO2 is 50% to 99% of the total coating weight. The ratio (Fe/Si) of the content of Fe to the content of Si in the insulating coating is 0.01 to 0.6 on a molar basis. The ratio (C (the organic resin+the lubricant)/(Fe2O3+SiO2)) of the coating weight of the organic resin and/or the lubricant in terms of C to the sum of the coating weight of Fe in terms of Fe2O3 and the coating weight of Si in terms of SiO2 preferably is 0.05 to 0.8.
    Type: Grant
    Filed: November 11, 2014
    Date of Patent: September 3, 2019
    Assignee: JFE Steel Corporation
    Inventors: Kazumichi Sashi, Nobuko Nakagawa, Naoki Muramatsu, Chiyoko Tada, Nobue Fujibayashi
  • Publication number: 20190160786
    Abstract: An electromagnetic steel sheet coated with an insulating film with excellent hardness and suitable for use as a material for iron cores of large-sized electric-power generators; and a process for producing the electromagnetic steel sheet coated with an insulating film. The purpose is achieved with a coating material for forming insulating films, the coating material including a solvent and components (A) to (C) contained therein in the respective amounts on a solid basis. (A) A water-compatible carboxylated resin; 100 parts by mass. (B) An aluminum-containing oxide; more than 40 parts by mass but less than 300 parts by mass per 100 parts by mass of the component (A). (C) At least one crosslinking agent selected from the group containing of melamine, isocyanates, and oxazoline; 100 parts by mass or more but less than 300 parts by mass per 100 parts by mass of the component (A).
    Type: Application
    Filed: August 1, 2017
    Publication date: May 30, 2019
    Applicant: JFE STEEL CORPORATION
    Inventors: Nobuko NAKAGAWA, Naoki MURAMATSU, Chiyoko TADA, Kengo NAKAMURA, Tomonori SUGISHITA
  • Publication number: 20180251869
    Abstract: The disclosure provides an electrical steel sheet with an insulating coating excellent in both punchability and powdering resistance, without any chromium compound being contained in the insulating coating. The electrical steel sheet with an insulating coating includes an electrical steel sheet and an insulating coating formed on the electrical steel sheet. The insulating coating contains Si and particulate organic resin. The organic resin contains primary particles having an average primary particle size of 1.0 ?m or less, and 5% or more and 50% or less of the primary particles of the organic resin are agglomerated particles.
    Type: Application
    Filed: April 5, 2016
    Publication date: September 6, 2018
    Applicant: JFE STEEL CORPORATION
    Inventors: Naoki MURAMATSU, Nobuko NAKAGAWA, Kazumichi SASHI, Chiyoko TADA
  • Publication number: 20170162295
    Abstract: An electrical steel sheet is provided with insulating coating. The insulating coating contains Si and Fe. The coating weight of Si in the insulating coating in terms of SiO2 is 50% to 99% of the total coating weight. The ratio (Fe/Si) of the content of Fe to the content of Si in the insulating coating is 0.01 to 0.6 on a molar basis. The ratio (C (the organic resin+the lubricant)/(Fe2O3+SiO2)) of the coating weight of the organic resin and/or the lubricant in terms of C to the sum of the coating weight of Fe in terms of Fe2O3 and the coating weight of Si in terms of SiO2 preferably is 0.05 to 0.8.
    Type: Application
    Filed: November 11, 2014
    Publication date: June 8, 2017
    Inventors: Kazumichi Sashi, Nobuko Nakagawa, Naoki Muramatsu, Chiyoko Tada, Nobue Fujibayashi
  • Publication number: 20170117758
    Abstract: A stacked electrical steel sheet used for a stacked iron core of an automotive motor and the like required to have high-temperature bond property and high-temperature oil resistance is provided. An electrical steel sheet for stacking includes: an electrical steel sheet; and a bond-type insulating coating formed on at least one surface of the electrical steel sheet and having Martens hardness HM of 50 or more and less than 500.
    Type: Application
    Filed: July 24, 2015
    Publication date: April 27, 2017
    Applicant: JFE STEEL CORPORATION
    Inventors: Nobuko NAKAGAWA, Kazumichi SASHI, Naoki MURAMATSU, Chiyoko TADA
  • Patent number: 9534136
    Abstract: A semi-organic insulation coating includes an inorganic component and an organic resin, a Zr compound and an Si compound contains a plate-like silica as an inorganic component and are included in a ratio in a dry coating of 20 to 70 mass % of Zr compound (converted to ZrO2) and 10 to 50 mass % of Si compound containing plate-like silica (converted to SiO2), and the remainder is substantially an organic resin, whereby a magnetic steel sheet with a semi-organic insulation coating has no deterioration of corrosion resistance and water resistance without containing a chromium compound and being excellent in powdering resistance, scratch resistance, sticking resistance, TIG weldability, punchability and coating appearance.
    Type: Grant
    Filed: July 21, 2011
    Date of Patent: January 3, 2017
    Assignee: JFE Steel Corporation
    Inventors: Kazumichi Sashi, Hiroyuki Ogata, Chiyoko Tada, Nobuko Nakagawa, Nobue Fujibayashi, Tomofumi Shigekuni, Kenichi Sasaki
  • Publication number: 20160230024
    Abstract: A coating material that forms an insulation coating, containing apart from a solvent: an aqueous carboxy group-containing resin as component (A) in an amount of 100 parts by mass in terms of solid content; an aluminum-containing oxide as component (B) in an amount of not less than 100 parts by mass but less than 300 parts by mass in terms of solid content, based on the component (A) present in an amount of 100 parts by mass in terms of solid content; and at least one crosslinking agent as component (C) selected from the group consisting of melamine, isocyanate and oxazoline, in an amount of more than 20 parts by mass but less than 100 parts by mass in terms of solid content, based on the component (A) present in an amount of 100 parts by mass in terms of solid content.
    Type: Application
    Filed: August 18, 2014
    Publication date: August 11, 2016
    Inventors: Nobuko Nakagawa, Chiyoko Tada, Kengo Nakamura, Hiroaki Kimura
  • Patent number: 8715837
    Abstract: A black-coated steel sheet exhibits good bendability and a good appearance after press working is provided. Zinc based plating layers, a chromium-free chemical conversion coating disposed on the zinc based plating layer, and a colored single organic coating which is disposed on the chemical conversion coating and which contains a polyester resin having a hydroxyl value of 10 KOHmg/g or more, an imino-containing melamine resin, and 5 to 15 percent by mass of carbon black are included, wherein the glass transition temperature (Tg) of the organic coating is 40° C. or higher, the film thickness is 10 ?m or less, and the hardness is 200 N/mm2 or more.
    Type: Grant
    Filed: September 8, 2009
    Date of Patent: May 6, 2014
    Assignee: JFE Steel Corporation
    Inventors: Chiyoko Tada, Hiroyuki Ogata
  • Publication number: 20130115444
    Abstract: A semi-organic insulation coating includes an inorganic component and an organic resin, a Zr compound and an Si compound contains a plate-like silica as an inorganic component and are included in a ratio in a dry coating of 20 to 70 mass % of Zr compound (converted to ZrO2) and 10 to 50 mass % of Si compound containing plate-like silica (converted to SiO2), and the remainder is substantially an organic resin, whereby a magnetic steel sheet with a semi-organic insulation coating has no deterioration of corrosion resistance and water resistance without containing a chromium compound and being excellent in powdering resistance, scratch resistance, sticking resistance, TIG weldability, punchability and coating appearance.
    Type: Application
    Filed: July 21, 2011
    Publication date: May 9, 2013
    Applicant: JFE STEEL CORPORATION
    Inventors: Kazumichi Sashi, Hiroyuki Ogata, Chiyoko Tada, Nobuko Nakagawa, Nobue Fujibayashi, Tomofumi Shigekuni, Kenichi Sasaki