Patents by Inventor Chikafumi Yokoyama

Chikafumi Yokoyama 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: 6548447
    Abstract: A process for the production of a mono-olefin from a gaseous paraffinic hydrocarbon having at least two carbon atoms or mixtures thereof comprising reacting the hydrocarbons and molecular oxygen in the presence of a platinum catalyst. The catalyst consists essentially of platinum modified with Sn or Cu and supported on a ceramic monolith.
    Type: Grant
    Filed: February 19, 1999
    Date of Patent: April 15, 2003
    Assignee: Regents of the University of Minnesota
    Inventors: Chikafumi Yokoyama, Sameer S. Bharadwaj, Lanny D. Schmidt
  • Patent number: 6537645
    Abstract: To provide a photosensitive paste capable of forming a rib having a predetermined shape with comparatively high accuracy, uniformly and rapidly, while inhibiting shrinkage and deformation in case of curing or calcination. A photosensitive paste comprising a ceramic powder, a binder of a silane coupling agent containing a methacrylic group and having a molecular weight of 232 to 290, and a glass powder having a softening point lower than that of a silica, characterized in that said glass powder is contained in the amount of 10-70% by volume based on the total amount of the powders.
    Type: Grant
    Filed: August 6, 2001
    Date of Patent: March 25, 2003
    Assignee: 3M Innovative Properties Company
    Inventors: Chikafumi Yokoyama, Toshihiro Kasai
  • Patent number: 6514892
    Abstract: Transparent solid, fused microspheres are provided. In one embodiment, the microspheres contain alumina, zirconia, and silica in a total content of at least about 70% by weight, based on the total weight of the solid, fused microspheres, wherein the total content of alumina and zirconia is greater than the content of silica, and further wherein the microspheres have an index of refraction of at least about 1.6 and are useful as lens elements.
    Type: Grant
    Filed: May 2, 2000
    Date of Patent: February 4, 2003
    Assignee: 3M Innovative Properties Company
    Inventors: Toshihiro Kasai, Kenton D. Budd, Stephen L. Lieder, James A. Laird, Chikafumi Yokoyama, Toshinori Naruse, Kenji Matsumoto, Hirohiko Ono
  • Publication number: 20030022585
    Abstract: An apparatus is provided for producing a substrate for PDP, which can easily reduce ununiformity of a dielectric layer and defects of ribs. The apparatus is so constituted that it comprises: a table for the plate, a rib precursor supplying portion for providing a precusor of the ribs on the plate, a pliable mold having at least groove portions provided in parallel with each other at a fixed distance, which is disposed on the precursor of the ribs provided on the plate, a mold pressing portion for applying a pressure to the mold, thereby to contact the mold closely with the plate via the precursor of the ribs, and a driving portion for moving the mold pressing portion along the groove portions of the mold.
    Type: Application
    Filed: June 17, 2002
    Publication date: January 30, 2003
    Inventors: Hiroshi Kikuchi, Chikafumi Yokoyama, Akira Yoda, Takaki Sugimoto, Toshihiro Suwa
  • Patent number: 6511739
    Abstract: Transparent solid, fused microspheres are provided. In one embodiment, the microspheres contain alumina, zirconia, and silica in a total content of at least about 70% by weight, based on the total weight of the solid, fused microspheres, wherein the total content of alumina and zirconia is greater than the content of silica, and further wherein the microspheres have an index of refraction of at least about 1.6 and are useful as lens elements.
    Type: Grant
    Filed: April 30, 2001
    Date of Patent: January 28, 2003
    Assignee: 3M Innovative Properties Company
    Inventors: Toshihiro Kasai, Kenton D. Budd, Stephen L. Lieder, James A. Laird, Chikafumi Yokoyama, Toshinori Naruse, Kenji Matsumoto, Hirohiko Ono
  • Patent number: 6479417
    Abstract: The present invention relates to transparent microspheres (i.e., beads) that impart yellow color to retroreflected light. The microsphere preferably comprise titania plus alumina, zirconia, and/or silica and iron oxide, manganese oxide, or mixtures thereof. More particularly, the present invention relates to fused microspheres that impart yellow color to retroreflected light having both transparency and mechanical properties suitable, for example, for lens elements in retroreflective articles.
    Type: Grant
    Filed: January 18, 2001
    Date of Patent: November 12, 2002
    Assignee: 3M Innovative Properties Company
    Inventors: Matthew H. Frey, Charles J. Studiner, III, Kenton D. Budd, Toshihro Kasai, Stephen B. Roscoe, Chikafumi Yokoyama, John E. Bailey
  • Patent number: 6461988
    Abstract: Transparent solid microspheres that contain titania plus alumina, zirconia, and/or silica in a total content of at least about 75% by weight, based on the total weight of the solid microspheres, wherein the total content of alumina, zirconia, and titania is greater than the content of silica.
    Type: Grant
    Filed: March 30, 2001
    Date of Patent: October 8, 2002
    Assignee: 3M Innovative Properties Company
    Inventors: Kenton D. Budd, Toshihiro Kasai, Stephen B. Roscoe, Chikafumi Yokoyama, John E. Bailey
  • Publication number: 20020013207
    Abstract: The present invention relates to transparent microspheres (i.e., beads) that impart yellow color to retroreflected light. The microsphere preferably comprise titania plus alumina, zirconia, and/or silica and iron oxide, manganese oxide, or mixtures thereof. More particularly, the present invention relates to fused microspheres that impart yellow color to retroreflected light having both transparency and mechanical properties suitable, for example, for lens elements in retroreflective articles.
    Type: Application
    Filed: January 18, 2001
    Publication date: January 31, 2002
    Applicant: 3M Innovative Properties Company
    Inventors: Matthew H. Frey, Charles J. Studiner, Kenton D. Budd, Toshihro Kasai, Stephen B. Roscoe, Chikafumi Yokoyama, John E. Bailey
  • Publication number: 20020007000
    Abstract: A molding composition is provided that includes an inorganic component, an organic binder component, and a debinding catalyst. The molding composition is capable of lowering the sintering temperature, for example, when the molding composition is used to make ceramic microstructures such as barrier ribs for plasma display panels.
    Type: Application
    Filed: August 28, 2001
    Publication date: January 17, 2002
    Applicant: 3M Innovative Properties Company
    Inventors: Chikafumi Yokoyama, Takaki Sugimoto, Chi-Hing Chiu
  • Publication number: 20020006510
    Abstract: Transparent solid microspheres that contain titania plus alumina, zirconia, and/or silica in a total content of at least about 75% by weight, based on the total weight of the solid microspheres, wherein the total content of alumina, zirconia, and titania is greater than the content of silica.
    Type: Application
    Filed: March 30, 2001
    Publication date: January 17, 2002
    Inventors: Kenton D. Budd, Toshihiro Kasai, Stephen B. Roscoe, Chikafumi Yokoyama, John E. Bailey
  • Patent number: 6335083
    Abstract: Transparent solid, fused microspheres are provided. In one embodiment, the microspheres contain alumina, zirconia, and silica in a total content of at least about 70% by weight, based on the total weight of the solid, fused microspheres, wherein the total content of alumina and zirconia is greater than the content of silica, and further wherein the microspheres have an index of refraction of at least about 1.6 and are useful as lens elements.
    Type: Grant
    Filed: April 17, 1998
    Date of Patent: January 1, 2002
    Assignee: 3M Innovative Properties Company
    Inventors: Toshihiro Kasai, Kenton D. Budd, Stephen L. Lieder, James A. Laird, Chikafumi Yokoyama, Toshinori Naruse, Kenji Matsumoto, Hirohiko Ono
  • Patent number: 6306948
    Abstract: A molding composition is provided that includes an inorganic component, an organic binder component, and a debinding catalyst. The molding composition is capable of lowering the sintering temperature, for example, when the molding composition is used to make ceramic microstructures such as barrier ribs for plasma display panels.
    Type: Grant
    Filed: October 26, 1999
    Date of Patent: October 23, 2001
    Assignee: 3M Innovative Properties Company
    Inventors: Chikafumi Yokoyama, Takaki Sugimoto, Chi-Hing Chiu
  • Publication number: 20010030811
    Abstract: Transparent solid, fused microspheres are provided. In one embodiment, the microspheres contain alumina, zirconia, and silica in a total content of at least about 70% by weight, based on the total weight of the solid, fused microspheres, wherein the total content of alumina and zirconia is greater than the content of silica, and further wherein the microspheres have an index of refraction of at least about 1.6 and are useful as lens elements.
    Type: Application
    Filed: April 30, 2001
    Publication date: October 18, 2001
    Applicant: 3M Innovative Properties Company
    Inventors: Toshihiro Kasai, Kenton D. Budd, Stephen L. Lieder, James A. Laird, Chikafumi Yokoyama, Toshinori Naruse, Kenji Matsumoto, Hirohiko Ono
  • Patent number: 6245700
    Abstract: Transparent solid microspheres that contain titania plus alumina, zirconia, and/or silica in a total content of at least about 75% by weight, based on the total weight of the solid microspheres, wherein the total content of alumina, zirconia, and titania is greater than the content of silica.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: June 12, 2001
    Assignee: 3M Innovative Properties Company
    Inventors: Kenton D. Budd, Toshihiro Kasai, Stephen B. Roscoe, Chikafumi Yokoyama, John E. Bailey
  • Patent number: 6072097
    Abstract: A process for the production of a mono-olefin from a gaseous paraffinic hydrocarbon having at least two carbon atoms or mixtures thereof comprising reacting said hydrocarbons and molecular oxygen in the presence of a platinum catalyst. The catalyst consists essentially of platinum modified with Sn or Cu and supported on a ceramic monolith.
    Type: Grant
    Filed: September 3, 1998
    Date of Patent: June 6, 2000
    Assignee: Regents of the University of Minnesota
    Inventors: Chikafumi Yokoyama, Sameer S. Bharadwaj, Lanny D. Schmidt
  • Patent number: 5905180
    Abstract: A process for the production of a mono-olefin from a gaseous paraffinic hydrocarbon having at least two carbon atoms or mixtures thereof comprising reacting said hydrocarbons and molecular oxygen in the presence of a platinum catalyst. The catalyst consists essentially of platinum modified with Sn or Cu and supported on a ceramic monolith.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: May 18, 1999
    Assignee: Regents of the University of Minnesota
    Inventors: Chikafumi Yokoyama, Sameer S. Bharadwaj, Lanny D. Schmidt