Patents by Inventor Shigeko Sujita

Shigeko Sujita 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: 20140174609
    Abstract: A method for manufacturing a high-strength steel sheet for a can, including (a) hot rolling a steel slab at a slab extraction temperature of 1200° C. or more and a finish rolling temperature of (Ar3 transformation temperature?30)° C. or more, the steel slab containing, on the basis of mass percent, more than 0.02%, but 0.10% or less of C, 0.10% or less of Si, 1.5% or less of Mn, 0.20% or less of P, 0.20% or less of S, 0.10% or less of Al, 0.0120% to 0.0250% of N, and the balance being Fe and incidental impurities; (b) coiling at a temperature of 650° C. or less; (c) pickling; (d) carrying out a first cold rolling; (e) continuously annealing; and (f) carrying out a second cold rolling at a reduction ratio of 10% or more and less than 20%.
    Type: Application
    Filed: March 3, 2014
    Publication date: June 26, 2014
    Applicant: JFE Steel Corporation
    Inventors: Makoto ARATANI, Toshikatsu KATO, Katsuhito KAWAMURA, Takumi TANAKA, Katsumi KOJIMA, Kaku SATO, Shigeko SUJITA, Masaki KOIZUMI
  • Publication number: 20110168303
    Abstract: A steel sheet for containers that has a hardness of 500 MPa or more and superior workability and a method for producing the steel sheet are provided. A steel containing, in percent by mass, 0.01% to 0.05% carbon, 0.04% or less silicon, 0.1% to 1.2% manganese, 0.10% or less sulfur, 0.001% to 0.100% aluminum, 0.10% or less nitrogen, and 0.0020% to 0.100% phosphorus, the balance being iron and incidental impurities, is subjected to hot rolling at a finishing temperature of (Ar3 transformation temperatute?30)° C. or more and a coiling temperature of 400° C. to 750° C., is subjected to pickling and cold rolling, is subjected to continuous annealing including overaging treatment, and is subjected to second cold rolling at a reduction rate of 20% to 50%, thus providing a high-strength steel sheet for containers that has a tensile strength of 500 MPa or more and a proof stress difference between width and rolling directions of 20 MPa or less.
    Type: Application
    Filed: April 10, 2009
    Publication date: July 14, 2011
    Inventors: Toshikatsu Kato, Makoto Aratani, Katsuhito Kawamura, Katsumi Kojima, Kaku Sato, Shigeko Sujita, Fumio Aoki
  • Publication number: 20110076177
    Abstract: A steel sheet for cans that has a yield stress of at least 500 Mpa after coating and baking and a method for manufacturing the steel sheet for cans are provided. The steel sheet for cans contains, on the basis of mass percent, C: more than 0.02% but 0.10% or less, Si: 0.10% or less, Mn: 1.5% or less, P: 0.20% or less, S: 0.20% or less, Al: 0.10% or less, N: 0.0120% to 0.0250%, dissolved N being 0.0100% or more, and a remainder of Fe and incidental impurities. A high-strength material can be obtained by maintaining the absolute quantity of dissolved N at a certain value or more and performing hardening by quench aging and strain aging, for example, in a printing process, a film lamination process, or a drying and baking process performed before can manufacturing. In the manufacture, hot rolling is performed at a slab extraction temperature of 1200° C. or more and a finish rolling temperature of (Ar3 transformation temperature—30)° C. or more, and coiling is performed at 650° C. or less.
    Type: Application
    Filed: April 1, 2009
    Publication date: March 31, 2011
    Applicant: JFE STEEL CORPORATION
    Inventors: Makoto Aratani, Toshikatsu Kato, Katsuhito Kawamura, Takumi Tanaka, Katsumi Kojima, Kaku Sato, Shigeko Sujita, Masaki Koizumi
  • Patent number: 5723210
    Abstract: An organic composite coated steel sheet having excellent chromate dissolution resistance, wet adhesion, and corrosion resistance before and after working. The steel sheet comprises a chromate-silica film on at least one face of a zinc or zinc base alloy plated steel sheet, the silica-added chromate film having about 5 to 500 mg/m.sup.2 in terms of metal Cr content and being formed from a chromate solution containing about 25 to 70 wt % of Cr.sup.+6 based upon total Cr content. A resin coating film is adhered to the chromate-silica film and is formed from an aqueous paint. The aqueous paint includes an aqueous anionic resin and/or an aqueous nonionic resin, a reducing agent, and a water-dispersed silica. The resin coating film is deposited in a dry weight amount of about 0.1 to 3 g/m.sup.2.
    Type: Grant
    Filed: May 29, 1996
    Date of Patent: March 3, 1998
    Assignees: Kawasaki Steel Corporation, Dai Nippon Toryo Co. Ltd.
    Inventors: Shigeko Sujita, Takahiro Kusakabe, Kyoko Hamahara, Kazuo Mochizuki, Hiroyuki Tanabe, Masanori Nagai, Nobuyoshi Kato, Osamu Ogawa
  • Patent number: 5514483
    Abstract: The improved organic composite coated steel plate includes a zinc or zinc alloy plated steel plate as a substrate that has on its surface a chromate film the Cr.sup.6+ content of which is no more than 70% of the total Cr content and which is deposited in an amount of 5-500 mg/m.sup.2 in terms of metallic chromium, the chromate film being overlaid with a resin layer that is deposited in an amount of 0.1-3 g/m.sup.2 on a dry weight basis and which is formed primarily of water-dispersed silica and one organic resin member as selected from the group consisting of an anionic aqueous resin, a nonionic aqueous resin and an anionic aqueous urethane resin. This steel plate is adapted for not contaminating the environment of the earth in the process of its manufacture.
    Type: Grant
    Filed: August 16, 1993
    Date of Patent: May 7, 1996
    Assignee: Kawasaki Steel Corporation
    Inventors: Shigeko Sujita, Ryoichi Muko, Kyoko Hamahara, Kazuo Mochizuki, Nobuyuki Morito
  • Patent number: 5482787
    Abstract: An organic composite coated steel strip having well-balanced corrosion resistance, coating properties including adaptability to electrophoretic coating and water resistant secondary coating adherence, and spot weldability is provided. The organic composite coated strip comprises a zinc or zinc base alloy plated steel substrate; a chromate later on the substrate containing up to 70% by weight of Cr.sup.6+ based on the total chromium quantity, the chromate layer being coated in a weight of 5 to 500 mg/m.sup.2 in terms of elemental chromium; and an organic composite layer on the chromate layer mainly comprising silica and an organic high molecular weight resin. In the organic composite coated steel strip, (a) silica has an average primary particle diameter of 5 to 30 nm; (b) silica is agglomerated into agglomerates of an average thickness of 0.2 to 2 .mu.m and an average apparent diameter of 5 to 300 .mu.m; and (c) the organic composite layer has been coated to a dry weight of 0.1 to 3 g/m.sup.2.
    Type: Grant
    Filed: October 12, 1993
    Date of Patent: January 9, 1996
    Assignee: Kawasaki Steel Corporation
    Inventors: Shigeko Sujita, Nobuyuki Morito
  • Patent number: 5185043
    Abstract: A grain oriented silicon steel sheet having a low iron loss and not causing degradation of properties even through strain relief annealing is produced by applying ultrasonic vibrations to the surface of the sheet after secondary recrystallization annealing.
    Type: Grant
    Filed: October 31, 1990
    Date of Patent: February 9, 1993
    Assignee: Kawasaki Steel Corporation
    Inventors: Ujihiro Nishike, Shigeko Sujita, Tsuneo Nagamine
  • Patent number: 5125991
    Abstract: A silicon-containing steel sheet having a low iron loss has such a crystal structure that crystal grains having an inclination angle of {110} face of not more than 10.degree. with respect to the sheet surface are included in an amount of not less than 80 vol % and exhibit a graining surface pattern in which boundaries of these crystal grains form stepwise difference or groove of not less than 0.4 .mu.m as a maximum height. This sheet is produced by subjecting a grain oriented silicon steel sheet after final annealing to a magnetically smoothening treatment by electrolysis in an squeous solution containing at least one of water soluble halides.
    Type: Grant
    Filed: October 19, 1990
    Date of Patent: June 30, 1992
    Assignee: Kawasaki Steel Corporation
    Inventors: Hirotake Ishitobi, Ujihiro Nishike, Shigeko Sujita, Tikara Kami, Yasuhiro Kobayashi
  • Patent number: 4963197
    Abstract: A grain oriented electromagnetic steel sheet having a very low iron loss is obtained by subjecting a surface of base metal in the sheet after finish annealing to a particular mechanical polishing and has a surface roughness having a center-line average roughness of not more than 0.3 .mu.m after the polishing and the number of abrasive grains embedded in a layer just beneath polished surface of not more than 20,000 grains/cm.sup.2.
    Type: Grant
    Filed: July 17, 1989
    Date of Patent: October 16, 1990
    Assignee: Kawasaki Steel Corp.
    Inventors: Ujihiro Nishiike, Yasuhiro Kobayashi, Hirotake Ishitobi, Shigeko Sujita, Norio Takahashi, Hisanao Nakahara, Yukio Inokuti