Patents Assigned to Daiki Engineering Co., Ltd.
-
Patent number: 6056862Abstract: Disclosed is a process for supplying nickel ions for a nickel alloy electroplating bath so as to replenish nickel ions consumed as electroplating progresses. The process uses an electrolysis cell, which is equipped with a rotatable cathode in the form of a drum or a disk having a surface of titanium or hard chromium plating; and an anode made of a titanium basket in which sulfur-containing metallic nickel is contained. Spent electroplating solution is electrolyzed in the electrolysis cell to dissolve nickel in the anode basket into the solution as ions and deposit a part of the dissolved nickel on the cathode, which is removed therefrom as the cathode rotates, while the rest of the dissolved nickel remains in the solution. The solution thus replenished with nickel ions is reused for the electroplating. The process may also be used to provide cobalt ions to replenish a spent cobalt alloy electroplating solution.Type: GrantFiled: October 28, 1998Date of Patent: May 2, 2000Assignee: Daiki Engineering Co., Ltd.Inventor: Naokazu Kumagai
-
Patent number: 5593556Abstract: The present invention provides highly durable electrodes for electrolysis, which are platinum group metal oxide-coated or composite oxide-coated Ti electrodes, comprising a sputtered film of a metal or an alloy consisting of at least one selected from the group of Ti, Zr, Nb and Ta to be transformed the metastable .beta. phase to the .alpha. phase in crystal structure by the heat treatment to prepare the active layer carried on the surface, as an intermediate layer at the interface between Ti substrate and electrocatalytic active layer, and method for preparation thereof. The electrodes allow stable electrolysis at low electrode potentials for long periods of time as highly durable electrodes for electrolysis, especially electrodes for oxygen evolution at high current density.Type: GrantFiled: February 6, 1995Date of Patent: January 14, 1997Assignee: Daiki Engineering Co., Ltd.Inventors: Naokazu Kumagai, Shuji Jikihara, Yoshimitsu Samata
-
Patent number: 5326736Abstract: This invention relates to a catalyst for cleaning exhaust gas, which is prepared by dipping in hydrofluoric acid an amorphous alloy composed of 20 to 80 atom % of one or more elements selected from the group consisting of Nb, Ta, Ti and Zr (the sum of Nb and Ta being up to 70 atom %), 0.5 to 20 atom % of one or more elements selected from the group consisting of Ru, Pd, Rh, Pt and Ir, and the balance of one or two of Ni and Co. This catalyst can clean at a low temperature an exhaust gas containing NO or CO discharged from apparatuses or engines wherein various organic substances are burnt.Type: GrantFiled: April 1, 1992Date of Patent: July 5, 1994Assignees: Koji Hashimoto, Daiki Engineering Co., Ltd.Inventors: Koji Hashimoto, Kiyohiro Teruuchi, Hiroki Habazaki, Asahi Kawashima, Katsuhiko Asami
-
Patent number: 5182007Abstract: A stain preventing method comprises: lining a conductive sheet on an article subjected to stain prevention; arranging an electrode member and a reference electrode in sea water; applying direct electric current using the conductive sheet as an anode and the electrode member as a cathode; allowing a current to flow while controlling a potential difference between the reference electrode and the anode to be in a certain range; and thereby giving electric shock to microorganisms which contact with the conductive sheet so as to prevent adhesion thereof. Stain prevention can be effectively carried out without generating substances harmful for life such as chlorine due to electrolysis of sea water.Type: GrantFiled: July 23, 1991Date of Patent: January 26, 1993Assignee: Daiki Engineering Co., Ltd.Inventors: Kazo Takagi, Shigeoki Nakamura, Chisei Murayama
-
Patent number: 4964967Abstract: 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: GrantFiled: February 16, 1990Date of Patent: October 23, 1990Assignees: Daiki Engineering Co., Ltd., Koji HashimotoInventors: Koji Hashimoto, Naokazu Kumagai, Katsuhiko Asami, Asahi Kawashima
-
Patent number: 4772773Abstract: 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: GrantFiled: February 18, 1986Date of Patent: September 20, 1988Assignees: Daiki Engineering Co., Ltd., Koji HashimotoInventors: Koji Hashimoto, Naokazu Kumagai, Katsuhiko Asami
-
Patent number: 4770949Abstract: 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: GrantFiled: August 4, 1986Date of Patent: September 13, 1988Assignees: Daiki Engineering Co., Ltd., Koji HashimotoInventors: Koji Hashimoto, Naokazu Kumagai, Katsuhiko Asami, Asahi Kawashima