Patents by Inventor Hideji Kuwajima
Hideji Kuwajima 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).
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Patent number: 8029701Abstract: There are disclosed a highly packed, mixed conductive powder with a relative packing density of at least 68%, a process for producing the same, a conductive paste using the mixed conductive powder and a process for producing the same, as well as a sheet and a sheet with attached film using the mixed conductive powder. This mixed conductive powder comprises substantially monodispersed conductive scale-like particles (A1) and conductive substantially spherical particles (B1). Or, this mixed conductive powder comprises substantially monodispersed, conductive, substantially spherical particles (A2) and conductive substantially spherical particles (B2) with a smaller particle diameter than that of the substantially spherical particles (A2).Type: GrantFiled: August 31, 2010Date of Patent: October 4, 2011Assignee: Hitachi Chemical Co., Ltd.Inventor: Hideji Kuwajima
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Publication number: 20100323198Abstract: There are disclosed a highly packed, mixed conductive powder with a relative packing density of at least 68%, a process for producing the same, a conductive paste using the mixed conductive powder and a process for producing the same, as well as a sheet and a sheet with attached film using the mixed conductive powder. This mixed conductive powder comprises substantially monodispersed conductive scale-like particles (A1) and conductive substantially spherical particles (B1). Or, this mixed conductive powder comprises substantially monodispersed, conductive, substantially spherical particles (A2) and conductive substantially spherical particles (B2) with a smaller particle diameter than that of the substantially spherical particles (A2).Type: ApplicationFiled: August 31, 2010Publication date: December 23, 2010Inventor: Hideji KUWAJIMA
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Patent number: 7790063Abstract: There are disclosed a highly packed, mixed conductive powder with a relative packing density of at least 68%, a process for producing the same, a conductive paste using the mixed conductive powder and a process for producing the same, as well as a sheet and a sheet with attached film using the mixed conductive powder. This mixed conductive powder comprises substantially monodispersed conductive scale-like particles (A1) and conductive substantially spherical particles (B1). Or, this mixed conductive powder comprises substantially monodispersed, conductive, substantially spherical particles (A2) and conductive substantially spherical particles (B2) with a smaller particle diameter than that of the substantially spherical particles (A2).Type: GrantFiled: September 22, 2004Date of Patent: September 7, 2010Assignee: Hitachi Chemical Company, Ltd.Inventor: Hideji Kuwajima
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Patent number: 7718090Abstract: The present invention provides an electroconductive paste that can contain a high proportion of an electroconductive powder, has excellent electroconductivity reliability and migration resistance, has a highly competitive price due to a reduced amount of silver plating, and is suitable for use in solder electrode formation, an electroconductive adhesive, etc. The electroconductive paste of the present invention comprises a binder and an electroconductive powder containing 80 to 97 wt % of a substantially spherical silver-coated copper powder in which the surface of a copper powder is coated with silver and the surface thereof is further coated with 0.02 to 0.5 wt % relative to the copper powder of a fatty acid, and 3 to 20 wt % of a flat-shaped silver-coated copper powder in which the surface of a copper powder is coated with silver and the surface thereof is further coated with 0.02 to 1.2 wt % relative to the copper powder of a fatty acid.Type: GrantFiled: November 13, 2003Date of Patent: May 18, 2010Assignee: Hitachi Chemical Co., Ltd.Inventors: Hideji Kuwajima, Jun-ichi Kikuchi, Kuniaki Satou
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Patent number: 7294289Abstract: Disclosed are conductive powder having a packing density of 68% by volume or more with a relative value preferably comprising 60 to 92% by weight of roughly spherical and silver-plated copper powder part of the surface of which has been coated with 3 to 30% by weight of silver based on an amount of roughly spherical copper powder with exposing at least a surface of a portion of an alloy of copper with silver, and the surface of which is coated with 0.02 to 1.0% by weight of an aliphatic acid based on an amount of the roughly spherical and silver-plated copper powder, and 8 to 40% by weight of silver powder, and a method for preparing the same.Type: GrantFiled: June 16, 2006Date of Patent: November 13, 2007Assignee: Hitachi Chemical Co., Ltd.Inventor: Hideji Kuwajima
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Publication number: 20070164260Abstract: There are disclosed a highly packed, mixed conductive powder with a relative packing density of at least 68%, a process for producing the same, a conductive paste using the mixed conductive powder and a process for producing the same, as well as a sheet and a sheet with attached film using the mixed conductive powder. This mixed conductive powder comprises substantially monodispersed conductive scale-like particles (A1) and conductive substantially spherical particles (B1). Or, this mixed conductive powder comprises substantially monodispersed, conductive, substantially spherical particles (A2) and conductive substantially spherical particles (B2) with a smaller particle diameter than that of the substantially spherical particles (A2).Type: ApplicationFiled: September 22, 2004Publication date: July 19, 2007Inventor: Hideji Kuwajima
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Publication number: 20060219985Abstract: Disclosed are conductive powder having a packing density of 68% by volume or more with a relative value preferably comprising 60 to 92% by weight of roughly spherical and silver-plated copper powder part of the surface of which has been coated with 3 to 30% by weight of silver based on an amount of roughly spherical copper powder with exposing at least a surface of a portion of an alloy of copper with silver, and the surface of which is coated with 0.02 to 1.0% by weight of an aliphatic acid based on an amount of the roughly spherical and silver-plated copper powder, and 8 to 40% by weight of silver powder, and a method for preparing the same.Type: ApplicationFiled: June 16, 2006Publication date: October 5, 2006Applicant: HITACHI CHEMICAL CO., LTD.Inventor: Hideji Kuwajima
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Patent number: 7083859Abstract: Disclosed are conductive powder having a packing density of 68% by volume or more with a relative value preferably comprising 60 to 92% by weight of roughly spherical and silver-plated copper powder part of the surface of which has been coated with 3 to 30% by weight of silver based on an amount of roughly spherical copper powder with exposing at least a surface of a portion of an alloy of copper with silver, and the surface of which is coated with 0.02 to 1.0% by weight of an aliphatic acid based on an amount of the roughly spherical and silver-plated copper powder, and 8 to 40% by weight of silver powder, and a method for preparing the same.Type: GrantFiled: July 7, 2004Date of Patent: August 1, 2006Assignee: Hitachi Chemical Co., Ltd.Inventor: Hideji Kuwajima
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Publication number: 20060145125Abstract: The present invention provides an electroconductive paste that can contain a high proportion of an electroconductive powder, has excellent electroconductivity reliability and migration resistance, has a highly competitive price due to a reduced amount of silver plating, and is suitable for use in solder electrode formation, an electroconductive adhesive, etc. The electroconductive paste of the present invention comprises a binder and an electroconductive powder containing 80 to 97 wt % of a substantially spherical silver-coated copper powder in which the surface of a copper powder is coated with silver and the surface thereof is further coated with 0.02 to 0.5 wt % relative to the copper powder of a fatty acid, and 3 to 20 wt % of a flat-shaped silver-coated copper powder in which the surface of a copper powder is coated with silver and the surface thereof is further coated with 0.02 to 1.2 wt % relative to the copper powder of a fatty acid.Type: ApplicationFiled: November 13, 2003Publication date: July 6, 2006Inventors: Hideji Kuwajima, Jun-ichi Kikuchi, Kuniaki Satou
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Publication number: 20050034560Abstract: Disclosed are conductive powder having a packing density of 68% by volume or more with a relative value preferably comprising 60 to 92% by weight of roughly spherical and silver-plated copper powder part of the surface of which has been coated with 3 to 30% by weight of silver based on an amount of roughly spherical copper powder with exposing at least a surface of a portion of an alloy of copper with silver, and the surface of which is coated with 0.02 to 1.0% by weight of an aliphatic acid based on an amount of the roughly spherical and silver-plated copper powder, and 8 to 40% by weight of silver powder, and a method for preparing the same.Type: ApplicationFiled: July 7, 2004Publication date: February 17, 2005Applicant: HITACHI CHEMICAL CO., LTD.Inventor: Hideji Kuwajima
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Patent number: 6515237Abstract: A through-hole wiring board comprising through-holes passing through a substrate and filled with an electroconductive material; copper toil lands and copper foil circuits formed on surfaces of the substrate; insulating layers formed on the copper toil circuits and between necessary portions of the copper foil lands and the copper foil circuits; and printed circuits (jumper circuits) formed by another electroconductive material having a different composition from that filling the through-holes on a part of the copper foil circuits, and the copper foil lands and the insulating layers except for unnecessary portions for electroconductivity; wherein the printed circuits and ends of the through-holes are electrically connected with an electroconductive material having a different composition from that filling the through-holes, permits easy formation of an electrical connection of the through-holes, has a high reliability on connection and is suitable for industrial production.Type: GrantFiled: November 21, 2001Date of Patent: February 4, 2003Assignee: Hitachi Chemical Company, Ltd.Inventors: Junichi Kikuchi, Kuniaki Sato, Hideji Kuwajima
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Publication number: 20020062990Abstract: A through-hole wiring board comprising through-holes passing through a substrate and filled with an electroconductive material; copper foil lands and copper foil circuits formed on surfaces of the substrate; insulating layers formed on the copper foil circuits and between necessary portions of the copper foil lands and the copper foil circuits; and printed circuits (jumper circuits) formed by another electroconductive material having a different composition from that filling the through-holes on a part of the copper foil circuits, and the copper foil lands and the insulating layers except for unnecessary portions for electroconductivity; wherein the printed circuits and ends of the through-holes are electrically connected with an electroconductive material having a different composition from that filling the through-holes, permits easy formation of an electrical connection of the through-holes, has a high reliability on connection and is suitable for industrial production.Type: ApplicationFiled: November 21, 2001Publication date: May 30, 2002Inventors: Junichi Kikuchi, Kuniaki Sato, Hideji Kuwajima
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Patent number: 6042933Abstract: Electroconductive composite metal powders comprising flat non-noble metal powders, each covered with a noble metal in an amount of 2 to 30% by weight in average based on the weight of the non-noble metal powders, on 50% or more in average of the whole surface area of the non-noble metal powders, interposing a layer of a mixture of the non-noble metal and noble metal between each non-noble metal powder and a noble metal covering layer, are suitable for providing an electroconductive paste after mixing with a binder, said paste showing excellent electroconductivity and prevention of migration.Type: GrantFiled: August 13, 1998Date of Patent: March 28, 2000Assignees: Hitachi Chemical Company, Ltd., Technopolis Hakodata Industrial Technology Promotion OrganizationInventors: Keizo Hirai, Hiroshi Wada, Akihiro Sasaki, Hisashi Kaga, Junichi Kikuchi, Shozo Yamana, Hideji Kuwajima
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Patent number: 5951918Abstract: An electroconductive paste for forming an electric circuit which is low in resistivity, high in electroconductivity and minimized in change of resistivity even after a thermal shock test and/or a humidity and DC applied test, can be obtained by using a composite electroconductive powder comprising a flake-like electroconductive powder made of a material such as silver, a silver alloy, a silver-coated copper powder or a silver-coated copper alloy powder and an unsteady-shaped electroconductive powder such as a reduced silver powder.Type: GrantFiled: August 5, 1997Date of Patent: September 14, 1999Assignee: Hitachi Chemical Company, Ltd.Inventors: Hideji Kuwajima, Shozo Yamana, Junichi Kikuchi, Hisashi Dokochi, Toshikazu Ono, Yoshikatsu Mikami, Hiroshi Wada
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Patent number: 5840432Abstract: Electroconductive composite metal powders comprising flat non-noble metal powders, each covered with a noble metal in an amount of 2 to 30% by weight in average based on the weight of the non-noble metal powders, on 50% or more in average of the whole surface area of the non-noble metal powders, interposing a layer of a mixture of the non-noble metal and noble metal between each non-noble metal powder and a noble metal covering layer, are suitable for providing an electroconductive paste after mixing with a binder, said paste showing excellent electroconductivity and prevention of migration.Type: GrantFiled: February 8, 1996Date of Patent: November 24, 1998Assignees: Hitachi Chemical Company, Ltd., Technopolis Hakodate Industrial TechnologyInventors: Keizo Hirai, Hiroshi Wada, Akihiro Sasaki, Hisashi Kaga, Junichi Kikuchi, Shozo Yamana, Hideji Kuwajima
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Patent number: 5194421Abstract: The present invention provides an oxide superconductor which is mainly composed of bismuth, lead, strontium, calcium, magnesium, and copper and has the composition represented by the formula:Bi.sub.1-A Pb.sub.A Sr.sub.1-B Mg.sub.B Ca.sub.1 Cu.sub.1.7.+-.0.3 Oxwherein A=0.15-0.35 and B=0.05-0.3 in which numerals represent atomic ratio and an oxide superconductor which is mainly composed of bismuth, lead, strontium, calcium, magnesium, barium and copper and has the composition represented by the formula:Bi.sub.1-A Pb.sub.A Sr.sub.1-(B+C) (Mg.sub.B Ba.sub.C)Ca.sub.1 Cu.sub.1.7.+-.0.3 Oxwherein A=0.15-0.35, B=0.05-0.3 and C=0.02-0.2 in which numerals represent atomic ratio. Methods for producing these superconductors are also provided.Type: GrantFiled: November 20, 1991Date of Patent: March 16, 1993Assignee: Hitachi Chemical CompanyInventors: Shuichiro Shimoda, Toranosuke Ashizawa, Keiji Sumiya, Hideji Kuwajima, Minoru Ishihara, Shozo Yamana
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Patent number: 5147851Abstract: A superconducting thick film circuit board or thick film superconductor obtained by forming a rod-like crystal superconducting composite layer comprising a superconductor made of a compound of M-Ba-Cu-O, M being Y and/or a lanthanide element, and a composite of Ag and Pt on a stabilized zirconia substrate has a high Jc value and good superconducting properties.Type: GrantFiled: October 30, 1989Date of Patent: September 15, 1992Assignee: Hitachi Chemical Company Ltd.Inventors: Shozo Yamana, Hideji Kuwajima, Minoru Ishihara, Keiji Sumiya, Toranosuke Ashizawa, Shuichiro Shimoda
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Patent number: 4576856Abstract: A reconstituted mica material produced by sheet forming a slurry containing mica flakes prepared by disintegrating unfired mica and comprising (i) mica flakes having a particle size of 1.7 mm or more and an aspect ratio of 150 or more, (ii) mica flakes having a particle size of 1.0 mm or more and less than 1.7 mm and an aspect ratio of 150 or more, (iii) mica flakes having a particle size of 0.25 mm or more and less than 1.0 mm and an aspect ratio of 100 or more, and (iv) mica flakes having a particle size of less than 0.25 mm and an aspect ratio of 100 or more, in definite ranges, gives reconstituted mica prepreg materials, reconstituted mica products and insulated coils having excellent mechanical and electrical properties.Type: GrantFiled: June 18, 1984Date of Patent: March 18, 1986Assignee: Hitachi Chemical Company, Ltd.Inventors: Hideji Kuwajima, Takeyoshi Watanabe
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Patent number: 4491618Abstract: A reconstituted mica material produced by sheet forming a slurry containing mica flakes prepared by disintegrating unfired mica and comprising (i) mica flakes having a particle size of 1.0 mm or more and an aspect ratio of 150 or more, (ii) mica flakes having a particle size of 0.25 mm or more and less than 1.0 mm and (iii) mica flakes having a particle size of less than 0.25 mm, in definite ranges, gives reconstituted mica prepreg materials, reconstituted mica products and insulated coils having excellent mechanical and electrical properties.Type: GrantFiled: November 6, 1981Date of Patent: January 1, 1985Assignee: Hitachi Chemical Company, Ltd.Inventors: Hideji Kuwajima, Kazuyoshi Shike, Takeyoshi Watanabe
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Patent number: 4165839Abstract: Mica flakes are disintegrated to mica scales having a diameter of 10 mm or less and a ratio of diameter/thickness of 100-1000 by using an apparatus and a method comprising bringing about coarse size reduction followed by size reduction of the mica flakes by high-pressure jets of water, if desired together with high-pressure jets of gas, separating mica scales from mica flakes by vertical classification followed by horizontal classification, and taking out the mica scales as a slurry while recycling nondisintegrated mica flakes to size reduction. The slurry of mica scales is used for making mica paper.Type: GrantFiled: April 19, 1978Date of Patent: August 28, 1979Assignee: Hitachi Chemical Company, Ltd.Inventors: Hideji Kuwajima, Hirofumi Mizoguchi, Juichi Sakurada, Takeyoshi Watanabe