Patents Assigned to Koji Hashimoto
  • Patent number: 5015352
    Abstract: A method for preparation of amorphous superlattice alloys consisting of lamellae based on periodic change in the composition by continuous conventional sputtering with a periodic change in the positions of substrates relative to a target or targets by rotating the substrate on a first axis and orbiting the substrate and first axis around a second axis parallel to the first axis.
    Type: Grant
    Filed: October 13, 1989
    Date of Patent: May 14, 1991
    Assignees: Yoshida Kogyo K.K., Koji Hashimoto
    Inventors: Koji Hashimoto, Hideaki Yoshioka, Katsuhiko Asami, Asahi Kawashima
  • Patent number: 4968363
    Abstract: A highly corrosion-resistant amorphous alloy composed of ni-- 15-80 atomic % Ta Ni-- 30-80 atomic % Ta, or Ni-- 20-50 atomic % Ta-- 10-23 atomic % P, with a specific amount of optional elements of Ti, Zr, Nb, W, Fe, Co, Cr, P, B, Si, or C.
    Type: Grant
    Filed: November 22, 1988
    Date of Patent: November 6, 1990
    Assignees: Mitsui Engineering & Shipbuilding Co., Ltd., Koji Hashimoto
    Inventors: Koji Hashimoto, Kazuo Shimamura, Asahi Kawashima, Katsuhiko Asami
  • Patent number: 4964967
    Abstract: Surface activated surface alloy electrodes and a process for preparing them high in corrosion resistance and activity, comprising a corrosion-resistant metal selected from, or a corrosion-resistant alloy composed of two or more metals selected from titanium, zirconium, niobium and tantalum, or a corrosion-resistant metal selected from, or a corrosion-resistant alloy composed of two or more metals selected from titanium, zirconium, niobium and tantalum clad with a corrosion-resistant metal selected from, or a corrosion-resistant alloy composed of two or more metals selected from titanium, zirconium, niobium and tantalum, or with any other metal or alloy, rolled or non-rolled, being used as a substrate metal or alloy; an alloy consisting of 20 to 67 atomic % of one or more metals selected from titanium, zirconium, niobium and tantalum, 0.
    Type: Grant
    Filed: February 16, 1990
    Date of Patent: October 23, 1990
    Assignees: Daiki Engineering Co., Ltd., Koji Hashimoto
    Inventors: Koji Hashimoto, Naokazu Kumagai, Katsuhiko Asami, Asahi Kawashima
  • Patent number: 4880482
    Abstract: A highly corrosion-resistant amorphous Cu alloys with at least one element selected from the group of Ta and Nb and other Cu-Ta alloys with at least one element selected from the group of Nb, Ti and Zr, wherein the total content of alloying elements other than Cu ranges from 15 to 85 at %.
    Type: Grant
    Filed: April 19, 1988
    Date of Patent: November 14, 1989
    Assignees: Mitsui Engineering & Shipbuilding Co., Ltd., Koji Hashimoto
    Inventors: Koji Hashimoto, Kimikado Miura, Katsuhiko Asami, Asahi Kawashima
  • Patent number: 4868073
    Abstract: A highly active powder catalyst with a high concentration of platinum group elements prepared from an amorphous alloy consisting of at least one of valve metals, at least one of platinum group elements and balance being at least one element selected from Ni and Co by immersion in a hydrofluoric acid, and a highly active electrode prepared by using the above mentioned powder catalyst.
    Type: Grant
    Filed: May 16, 1988
    Date of Patent: September 19, 1989
    Assignees: Yanmar Diesel Engine Co., Ltd., Koji Hashimoto
    Inventors: Koji Hashimoto, Toshihisa Kanda, Asahi Kawashima, Katsuhiko Asami
  • Patent number: 4772773
    Abstract: Methods for preparation of overlaid uniform amorphous alloy layers of prescribed compositions and thicknesses bonded tightly to the substrate metals are described. The methods involve previously coating the substrate metal surface with metal layers and irradiating with high energy density beams to cause a melting of the metal layer or layers including, if necessary, a portion of the substrate metal and thereby forming a uniform alloy metal of prescribed composition tightly bonded to the substrate metal surface, said irradiation being carried out during movement of the substrate or beams so as to control irradiation time and depth.
    Type: Grant
    Filed: February 18, 1986
    Date of Patent: September 20, 1988
    Assignees: Daiki Engineering Co., Ltd., Koji Hashimoto
    Inventors: Koji Hashimoto, Naokazu Kumagai, Katsuhiko Asami
  • Patent number: 4770949
    Abstract: Electrode materials and method for their surface activation are described. Alloys consisting of at least one element of the group consisting of Nb, Ta, Ti and Zr, at least one element of the group consisting of Ru, Rh, Pd, Ir and Pt, and balance being Ni are prepared by methods for preparation of amorphous alloys, and are amorphous or supersaturated solid solution. Their surfaces are activated to enhance electrocatalytic activity by enrichment of electrocatalytically active platinum group elements in the surface region in addition to surface roughening as a result of selective dissolution of Ni, Nb, Ta, Ti and Zr from the alloys during immersion in corrosive solutions. The surface-activated amorphous and supersaturated solid solution alloys possess high electrocatalytic activity and selectivity for a specific reaction as well as high corrosion resistance.
    Type: Grant
    Filed: August 4, 1986
    Date of Patent: September 13, 1988
    Assignees: Daiki Engineering Co., Ltd., Koji Hashimoto
    Inventors: Koji Hashimoto, Naokazu Kumagai, Katsuhiko Asami, Asahi Kawashima
  • Patent number: 4743314
    Abstract: A highly corrosion-resistant amorphous Ni-Cu-Ti-Ta, Ni-Cu-Ti-Nb and Ni-Cu-Ti-Ta-Nb alloys in which the sum of Ti and Ta and/or Nb is 30-62.5 atomic %.
    Type: Grant
    Filed: September 21, 1987
    Date of Patent: May 10, 1988
    Assignees: Mitsui Engineering & Shipbuilding Co., Ltd., Koji Hashimoto
    Inventors: Koji Hashimoto, Kimikado Miura, Katsuhiko Asami, Asahi Kawashima
  • Patent number: 4339270
    Abstract: An amorphous alloy is prepared by rapid quenching from the liquid state and consists of(1) 10 to 40 atomic percent of P and/or Si(2) 90 to 60 atomic percent of two or more of Pd, Rh and Pt.The amorphous alloy is used for an electrode for an electrolysis.
    Type: Grant
    Filed: April 14, 1980
    Date of Patent: July 13, 1982
    Assignees: Toyo Soda Manufacturing Co. Ltd., Koji Hashimoto
    Inventors: Koji Hashimoto, Tsuyoshi Masumoto, Motoi Hara, Katsuhiko Asami, Kazutaka Sakiyama