Patents by Inventor Seiichi Yokoyama

Seiichi 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: 5851841
    Abstract: A method for producing a ferroelectric element having a lower electrode layer, a ferroelectric film and an upper electrode layer provided in sequence on the substrate is disclosed. The method comprising the step of applying a metal-contained precursor solution to the surface of the lower electrode layer formed on the substrate, the step of drying the applied precursor solution to remove the solution alone by heating it, a first heat treatment step for heating the dried precursor to form a ferroelectric film, and a second heat treatment step for heating the formed film element in a gas-pressurized atmosphere of lower than 1 atmosphere after forming an upper electrode layer on the ferroelectric film.
    Type: Grant
    Filed: September 13, 1996
    Date of Patent: December 22, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Maho Ushikubo, Yasuyuki Ito, Seiichi Yokoyama, Hironori Matsunaga, Masayoshi Koba
  • Patent number: 5831299
    Abstract: A thin ferroelectric film element comprises upper and lower thin electrode films and a thin ferroelectric film formed on a substrate, wherein the thin ferroelectric film comprises at least three layers in which at least one layer has a composition of constituent elements different from those of the other layers and a resistivity higher than that of the other layers, and at least two layers of the others are the same composition of constituent element.
    Type: Grant
    Filed: March 19, 1997
    Date of Patent: November 3, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Seiichi Yokoyama, Yasuyuki Ito, Maho Ushikubo, Masayoshi Koba
  • Patent number: 5824552
    Abstract: A method is disclosed for culturing animal cells in a medium characterized n that said medium contains a compound represented by the general formula ##STR1## wherein, R denotes COOM or CHO, herein M denotes hydrogen, an alkali metal or a C.sub.1 to C.sub.3 alkyl group, and n is an integer of 1 to 3.According to the present method, proliferation of animal cells can be enhanced with good reproducibility.
    Type: Grant
    Filed: August 15, 1996
    Date of Patent: October 20, 1998
    Assignees: Teijin Limited, Juridical Foundation The Chemo-Sero-Therapeutic Research Institute
    Inventors: Yoshiharu Takazawa, Takami Arai, Masamichi Motoki, Kenji Nagura, Seiichi Yokoyama, Yoshinobu Miyatsu, Hiroshi Mizokami
  • Patent number: 5776356
    Abstract: A method for etching a ferroelectric film made of a compound containing lead of the present invention, includes the steps of: forming an insulating film, metal films, and a ferroelectric film on a substrate in this order; forming an etching resistant film on the ferroelectric film, followed by patterning; and etching the ferroelectric film with a mixed gas containing an inert gas and a halogen gas or a halogenated gas as an etching gas, using the patterned etching resistant film as an etching mask.
    Type: Grant
    Filed: February 15, 1995
    Date of Patent: July 7, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Seiichi Yokoyama, Yasuyuki Itoh, Shigeo Onishi, Jun Kudo, Keizo Sakiyama, Hitoshi Urashima
  • Patent number: 5515984
    Abstract: A method for etching a Pt film of the present invention includes the steps of: forming an etching resistant film on a Pt film, followed by patterning; etching the Pt film by using as an etching mask the etching resistant film and by using, as an etching gas, a mixed gas containing oxygen gas and chlorine gas or chloride gas, during which layers made of PtCl.sub.x O.sub.y or a mixture containing PtCl.sub.x and PtO.sub.y are formed on side walls of the etching resistant film and the Pt film; and removing the layers made of PtCl.sub.x O.sub.y or the mixture containing PtCl.sub.x and PtO.sub.y with an acid by wet etching after the etching step.
    Type: Grant
    Filed: January 24, 1995
    Date of Patent: May 14, 1996
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Seiichi Yokoyama, Yasuyuki Ito, Shigeo Onishi, Jun Kudo, Keizo Sakiyama
  • Patent number: 5443968
    Abstract: In a process of production of a useful protein by culturing a human embryonal kidney cell-derived 293 strain which is introduced with a useful protein-expressing gene, it becomes possible to obtain a culture fluid containing the useful protein in a high concentration using an extremely small amount of the medium, by carrying out a fed-batch culture and adding a sugar or a sugar and a calcium in a specified stage of the culture.
    Type: Grant
    Filed: January 3, 1994
    Date of Patent: August 22, 1995
    Assignee: Teijin Limited
    Inventors: Yoshiharu Takazawa, Seiichi Yokoyama
  • Patent number: 5216687
    Abstract: A solid-state laser device which employs a bi-cylindrical lens as a focusing lens for focusing excitation light emitted from a semiconductor laser to pump a laser medium. Further, the radius of curvature of each cylindrical surface of the bi-cylindrical lens is selected such that a region of the laser medium to be pumped by a horizontal component of the pumping light and another region of the laser medium to be pumped by a vertical component of the pumping light are contained in a predetermined region of the laser medium. Thereby, output laser light which excels in transverse mode characteristics can be efficiently obtained without increasing the number of surfaces of lenses composing the focusing lens system. Moreover, there is provided a solid-state laser device which can be relatively small-sized and easily regulated.
    Type: Grant
    Filed: July 16, 1991
    Date of Patent: June 1, 1993
    Assignee: Hoya Corporation
    Inventors: Masashi Fujino, Seiichi Yokoyama
  • Patent number: 5130996
    Abstract: In a solid-state laser device comprising, as a solid-state laser medium, a nonlinear optical crystal, such as Nd.sub.x Y.sub.1-x Al.sub.3 (BO.sub.3).sub.4, which generates a primary laser beam of a fundamental wavelength and which can convert the primary laser beam into a subsidiary laser beam of a harmonic wavelength, a pair of optical elements is brought into contact with both ends of the solid-state laser medium to form a resonator for the primary laser beam. The optical elements may be composed of optical thin films or reflectors attached to the ends of the medium. At least one of the ends of the medium has a spherical surface convex outwards of the medium so as to reflect the primary laser beam into the medium.
    Type: Grant
    Filed: November 30, 1990
    Date of Patent: July 14, 1992
    Assignee: Hoya Corporation
    Inventors: Sho Amano, Seiichi Yokoyama
  • Patent number: 4345089
    Abstract: Disclosed is a process for the recovery of aromatic carboxylic acid or ester thereof from the residue fraction of the oxidation or esterification reaction mixture resulting from the oxidation or oxidation and esterification of an aromatic compound having at least one methyl or formyl group directly bonded to a ring carbon atom. The process comprises treating the residue fraction with hydrogen and a hydrogenation catalyst.
    Type: Grant
    Filed: April 28, 1980
    Date of Patent: August 17, 1982
    Assignee: Hercofina
    Inventors: Kenji Nagura, Shinichi Takeda, Koshi Namie, Takao Fujii, Michio Yamamoto, Seiichi Yokoyama
  • Patent number: 3957896
    Abstract: A process for preparing 2,6-dimethylnaphthalene by the selective isomerization of an isomeric mixture of dimethylnaphthalenes(DMN), characterized in that1. the weight ratio of DMN of group A which includes 2,6-DMN, 1,6-DMN, and 1,5-DMN to other DMN (not belonging to group A) in the isomerization reactant is adjusted to not more than 12,2. the weight percent of 2,6-DMN in the reaction product is adjusted to at least 27 based on the DMN of group A contained therein,3. the disproportionation ratio D (weight percent) of other DMN (not belonging to group A) and the conversion G (weight percent) of DMN of group A to other DMN satisfy the relation expressed by D.ltoreq. -0.9G + 6.76, and4. the residue in the crystallization step is recycled to the isomerization step.
    Type: Grant
    Filed: May 30, 1974
    Date of Patent: May 18, 1976
    Assignee: Teijin Limited
    Inventors: Seiichi Yokoyama, Takanori Urasaki, Michiyuki Tokashiki, Takeo Shima