Patents by Inventor Junzo Fukuda

Junzo Fukuda 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: 5601638
    Abstract: A thick film paste for use in the formation of a conductor, a resistor, an insulator, a protector or the like in a ceramic wiring substrate by a printing process, wherein at least 2-tetradecanol as a solvent is contained in an amount of at least 3% by weight. The thick film paste is excellent in printability, for example, has less viscosity change during printing and exhibits less bleeding.
    Type: Grant
    Filed: November 20, 1995
    Date of Patent: February 11, 1997
    Assignees: Sumitomo Metal (SMI) Electronics Devices Inc., Daiken Chemical Company
    Inventors: Junzo Fukuda, Akio Harada, Susumu Nishigaki
  • Patent number: 4795670
    Abstract: A multilayer ceramic substrate with multilayered circuit patterns, the improvement in which internal conductors for wiring are formed by a Ag base conductive materials capable of being co-fired with multilayered green ceramic substrate sheets in an oxidizing atmosphere and external conductors electrically connected with the internal conductors are formed by a Cu base conductive material, the external Cu conductors being formed in such a manner so that a liquid phase of Cu-Ag is not formed at the interface of the Cu conductor and the Ag conductor. Further high reliable resistors of RuO.sub.2 or Bi.sub.2 Ru.sub.2 O.sub.7 type may be integrally formed onto and/or inside the substrate. In such an arrangement, problems or difficulties caused due to Ag migration, incomplete binder removal, solder leaching, etc., are eliminated and thereby there can be a multilayer substrate with a high reliability and a high pattern precision.
    Type: Grant
    Filed: May 8, 1987
    Date of Patent: January 3, 1989
    Assignee: Narumi China Corporation
    Inventors: Susumu Nishigaki, Junzo Fukuda, Shinsuke Yano, Hiroshi Kawabe
  • Patent number: 4748085
    Abstract: In a multilayer ceramic circuit board comprising a substrate, an insulating layer on the substrate, and a conductive pattern on the insulating layer, an additive of Cr.sub.2 O.sub.3 or MnO.sub.2 is added to the insulating layer to reinforce adhesion between the insulating layer and the conductive pattern. Each of the substrate and the insulating layer is manufactured by firing at a temperature between 800.degree. C. and 1000.degree. C., alumina particles and a glass composition comprising an alumina component. When a total amount of alumina in the substrate is equal to or greater than that in the insulating layer, an amount of Cr.sub.2 O.sub.3 or MnO.sub.2 is restricted to a range between 0.1% and 10.0% by weight, with a difference between the total amounts of alumina falling within a range between 0% and 30% by weight. When the total amount of alumina in the substrate is smaller than that in the insulating layer, the amounts of Cr.sub.2 O.sub.3 and MnO.sub.2 may be between 0.1% and 10.
    Type: Grant
    Filed: November 14, 1986
    Date of Patent: May 31, 1988
    Assignee: Narumi China Corporation
    Inventors: Junzo Fukuda, Masashi Fukaya, Hiroshi Kawabe, Susumu Nishigaki
  • Patent number: 4726921
    Abstract: Low temperature fired ceramics are produced by a highly improved method, using a specially designed apparatus and the obtained ceramic products are very useful in various applications, such as electronic components, heat resistant articles, tablewares, kitchen utensils or decorative articles because of a combination of superior properties, particularly high heat resistance, high mechanical strength, low thermal expansion and low dielectric constant. In practicing the method, a low firable ceramic material is shaped into a green sheet and then converted to a dense fired ceramic product by rapid firing in an adequate air. In the firing step, the air feed ratio (the ratio of the quantity of feed of air to the theoretical quantity of air required for combustion) is controlled so as to be at least 1.5 thereby the aimed fired products can be obtained in a greatly reduced firing time, without causing deformation or warpage of the ceramics or ignition of the decomposition gases of a binder.
    Type: Grant
    Filed: May 24, 1985
    Date of Patent: February 23, 1988
    Assignee: Narumi China Corporation
    Inventors: Susumu Nishigaki, Masashi Fukaya, Junzo Fukuda, Shinsuke Yano, Osamu Nakagawa
  • Patent number: 4650923
    Abstract: In an article comprising a ceramic body fired at a comparatively low temperature and a circuit pattern attached to the body, the ceramic body is produced from a preselected composition comprising first powder of alumina and second powder of a vitreous material which comprises any one of MgO-Al.sub.2 O.sub.3 -SiO.sub.2, CaO-MgO-Al.sub.2 O.sub.3 -SiO.sub.2, CaO-Al.sub.2 O.sub.3 -SiO.sub.2 glass, CaO-Al.sub.2 O.sub.3 -SiO.sub.2 -B.sub.2 O.sub.3 glass, MgO-Al.sub.2 O.sub.3 -SiO.sub.2 -B.sub.2 O.sub.3 glass, and CaO-MgO-Al.sub.2 O.sub.3 SiO.sub.2 -B.sub.2 O.sub.3 glass. The ceramic body comprises coexistence of an alumina part, a noncrystallized part, and a crystallized part and exhibits an excellent moisture proof. The circuit pattern comprises an internal conductive pattern of Ag and an external conductive pattern of an alloy of Ag-Pd. A chromium component may be included in the internal and the external conductive patterns.
    Type: Grant
    Filed: May 31, 1985
    Date of Patent: March 17, 1987
    Assignee: Narumi China Corporation
    Inventors: Susumu Nishigaki, Junzo Fukuda, Masashi Fukaya, Shinsuke Yano
  • Patent number: 4496509
    Abstract: A method of preparing green ceramic tapes, comprising adding to 100 parts by weight of a fine ceramic powder, 2 to 15 parts by weight, in terms of its resin content, of a binder mixture consisting of an aqueous polyurethane and a water-soluble acrylic resin, the amount of said water-soluble acrylic resin ranging from 10 to 1500 parts by weight per 100 parts by weight of said aqueous polyurethane in said binder mixture, adding a small amount of a dispersing agent to the mixture followed by a sufficient amount of water, kneading the resultant mixture for a time sufficient to prepare an aqueous slip, forming a tape in a known manner from said aqueous, and then drying the green tape obtained.
    Type: Grant
    Filed: April 26, 1983
    Date of Patent: January 29, 1985
    Assignees: Narumi China Corporation, Kao Soap Co., Ltd.
    Inventors: Katsuhiko Kita, Junzo Fukuda, Shiro Kawahito
  • Patent number: 4353958
    Abstract: Green ceramic tapes are prepared which comprise a finely divided ceramic powder and a water-compatible polyurethane resin binder. The green tapes are prepared by casting a water-based slip containing the ceramic powder and the water-compatible polyurethane resin binder in the form of the tape and then drying the formed tape. The drying is preferably conducted in two stages, in the first of which a relatively humid atmosphere is maintained.
    Type: Grant
    Filed: March 20, 1980
    Date of Patent: October 12, 1982
    Assignees: Narumi China Corporation, Kao Soap Co., Ltd.
    Inventors: Katsuhiko Kita, Junzo Fukuda, Hidemasa Ohmura, Takeya Sakai