Patents by Inventor Yasuhiro Kamahori

Yasuhiro Kamahori 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).

  • Patent number: 7785499
    Abstract: The invention provides a nickel-rhenium alloy powder that contains nickel as a main component, 0.1 to 10% by weight of rhenium and 50 to 10,000 ppm of silicon in terms of silicon atoms, and that is suitable, in particular, for the formation of an internal electrode layer for a multilayer ceramic electronic component. The obtained powder is homogeneously mixed and dispersed in an organic vehicle, together with other additives as needed, to prepare a conductor paste. When used in particular for forming an internal electrode of a multilayer ceramic electronic component, the nickel-rhenium alloy powder of the invention delays sintering initiation and slows down the progress of sintering during firing, even for extremely fine powders, while bringing the sintering shrinkage behaviors of electrode layers and ceramic layers closer to each other. Moreover, there occurs no electrode spheroidizing caused by oversintering. A thinner, dense internal electrode having excellent continuity can be formed as a result.
    Type: Grant
    Filed: September 25, 2007
    Date of Patent: August 31, 2010
    Assignee: Shoei Chemical Inc.
    Inventors: Yuji Akimoto, Kazuro Nagashima, Tetsuya Kimura, Yasuhiro Kamahori
  • Patent number: 7744779
    Abstract: A nickel-rhenium alloy powder comprising nickel as a main component, 0.1 to 10% by weight of rhenium, and having an average particle size of 0.05 to 1.0 ?m is provided. The nickel-rhenium alloy powder has a surface oxide film containing a nickel oxide and a rhenium oxide, and the amount of oxygen in the surface oxide film is 0.1 to 3.0% by weight relative to the total weight of the powder. The nickel-rhenium alloy powder is suitable, in particular, for forming internal electrode layers of a multilayer ceramic electronic component. The obtained powder is homogeneously mixed and dispersed in an organic vehicle, together with other additives as needed, to prepare a conductor paste. The surface oxide film allows bringing the sintering shrinkage behavior of electrode layers and ceramic layers closer to each other when the nickel-rhenium alloy powder is used, in particular, for forming internal electrodes of a multilayer ceramic electronic component.
    Type: Grant
    Filed: September 25, 2007
    Date of Patent: June 29, 2010
    Assignee: Shoei Chemical Inc.
    Inventors: Yuji Akimoto, Kazuro Nagashima, Tetsuya Kimura, Yasuhiro Kamahori
  • Publication number: 20100021735
    Abstract: A nickel-rhenium alloy powder comprising nickel as a main component, 0.1 to 10% by weight of rhenium, and having an average particle size of 0.05 to 1.0 ?m is provided. The nickel-rhenium alloy powder has a surface oxide film containing a nickel oxide and a rhenium oxide, and the amount of oxygen in the surface oxide film is 0.1 to 3.0% by weight relative to the total weight of the powder. The nickel-rhenium alloy powder is suitable, in particular, for forming internal electrode layers of a multilayer ceramic electronic component. The obtained powder is homogeneously mixed and dispersed in an organic vehicle, together with other additives as needed, to prepare a conductor paste. The surface oxide film allows bringing the sintering shrinkage behavior of electrode layers and ceramic layers closer to each other when the nickel-rhenium alloy powder is used, in particular, for forming internal electrodes of a multilayer ceramic electronic component.
    Type: Application
    Filed: September 25, 2007
    Publication date: January 28, 2010
    Inventors: Yuji Akimoto, Kazuro Nagashima, Tetsuya Kimura, Yasuhiro Kamahori
  • Publication number: 20090321690
    Abstract: The invention provides a nickel-rhenium alloy powder that comprises nickel as a main component, 0.1 to 10% by weight of rhenium and 50 to 10,000 ppm of silicon in terms of silicon atoms, and that is suitable, in particular, for the formation of an internal electrode layer for a multilayer ceramic electronic component. The obtained powder is homogeneously mixed and dispersed in an organic vehicle, together with other additives as needed, to prepare a conductor paste. When used in particular for forming an internal electrode of a multilayer ceramic electronic component, the nickel-rhenium alloy powder of the invention delays sintering initiation and slows down sintering progress during firing, even for extremely fine powders, while bringing the sintering shrinkage behaviors of electrode layers and ceramic layers closer to each other. Moreover, there occurs no electrode spheroidizing caused by oversintering. A thinner, dense internal electrode having excellent continuity can be formed as a result.
    Type: Application
    Filed: September 25, 2007
    Publication date: December 31, 2009
    Inventors: Yuji Akimoto, Kazuro Nagashima, Tetsuya Kimura, Yasuhiro Kamahori
  • Patent number: 7503959
    Abstract: Metal particles that can be alloyed with rhenium are dispersed as a main component in a gas phase, a rhenium oxide vapor is made to be present around these particles, the rhenium oxide is reduced, and the rhenium precipitated on the surface of the main component metal particles as a result of this reduction is diffused under a high temperature into the main component metal particles, which gives a rhenium-containing alloy powder including the main component metal and rhenium. The powder thus obtained preferably contains 0.01 to 50 wt % rhenium, has an average particle size of 0.01 to 10 ?m, and is made into a conductor paste by being uniformly mixed and dispersed in an organic vehicle along with other additives as needed.
    Type: Grant
    Filed: October 16, 2006
    Date of Patent: March 17, 2009
    Assignee: Shoei Chemical Inc.
    Inventors: Yuji Akimoto, Kazuro Nagashima, Masayuki Maekawa, Hidenori Ieda, Yasuhiro Kamahori
  • Publication number: 20070084309
    Abstract: Metal particles that can be alloyed with rhenium are dispersed as a main component in a gas phase, a rhenium oxide vapor is made to be present around these particles, the rhenium oxide is reduced, and the rhenium precipitated on the surface of the main component metal particles as a result of this reduction is diffused under a high temperature into the main component metal particles, which gives a rhenium-containing alloy powder including the main component metal and rhenium. The powder thus obtained preferably contains 0.01 to 50 wt % rhenium, has an average particle size of 0.01 to 10 ?m, and is made into a conductor paste by being uniformly mixed and dispersed in an organic vehicle along with other additives as needed.
    Type: Application
    Filed: October 16, 2006
    Publication date: April 19, 2007
    Inventors: Yuji Akimoto, Kazuro Nagashima, Masayuki Maekawa, Hidenori Ieda, Yasuhiro Kamahori