Patents by Inventor Hiroyoshi Nawa

Hiroyoshi Nawa 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: 5290361
    Abstract: A combination of a first surface treating solution comprising an inorganic or organic alkali such as ammonia or a quaternary ammonium hydroxide, hydrogen peroxide, water and a second surface treating solution of ultra-pure water, at least one of the first and second surface treating solutions containing as a complexing agent a compound having one or more phosphonic acid groups in the molecule and showing chelating ability, or an oxidized form thereof, or polyphosphoric acid or a salt thereof, is effective for making semiconductor surfaces free from harmful metallic impurities such as Fe, Al, Zn, etc.
    Type: Grant
    Filed: January 23, 1992
    Date of Patent: March 1, 1994
    Assignees: Wako Pure Chemical Industries, Ltd., Purex Co., Ltd.
    Inventors: Ichiro Hayashida, Masahiko Kakizawa, Kenichi Umekita, Hiroyoshi Nawa, Hisashi Muraoka
  • Patent number: 5081243
    Abstract: 3-Tetrazolylpyrido[1,2-a]pyrimidin-4-one derivatives useful as an antiallergy agent are produced by reacting a cyano derivative of pyrido[1,2-a]pyrimidin-4-one compound with (i) hydrazoic acid, followed by hydrolysis, or with (ii) a salt of hydrazoic acid, reacting the resulting product with an acid or a base, followed by hydrolysis.
    Type: Grant
    Filed: February 22, 1990
    Date of Patent: January 14, 1992
    Assignees: Wako Pure Chemical Industries, Ltd., Tokyo, Tanabe Co., Ltd.
    Inventors: Atsunori Sano, Masami Ishihara, Jun Yoshihara, Hiroyoshi Nawa
  • Patent number: 5000880
    Abstract: Glycero-phosphatidylcholine is acylated with a higher fatty acid anhydride in the presence of a special organic solvent in the absence of a catalyst.
    Type: Grant
    Filed: June 1, 1989
    Date of Patent: March 19, 1991
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Masami Ishihara, Hiroyoshi Nawa, Tsutomu Miyagawa
  • Patent number: 4950742
    Abstract: An azoimino ether, which is an intermediate for preparing polymerization initiators, is prepared by reacting a hydrazonitrile having a hydrazo group and at least one cyano group in the molecule with chlorine in the presence of an alcohol, in a non-aqueous organic solvent.
    Type: Grant
    Filed: March 6, 1989
    Date of Patent: August 21, 1990
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Kazuo Ichiriki, Motoaki Tanaka, Toru Okugawa, Hiroyoshi Nawa
  • Patent number: 4851572
    Abstract: A .gamma.-L-glutamyl-4-nitroanilide derivative of the formula: ##STR1## wherein R is a lower hydroxyalkyl group, is suitable as a substrate for determining .gamma.-GTP activity.
    Type: Grant
    Filed: July 1, 1988
    Date of Patent: July 25, 1989
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Hiroshi Ogata, Hiroyoshi Nawa, Kuniaki Tokuda, Masami Ishihara
  • Patent number: 4578499
    Abstract: Disclosure herein is novel oxalic acid ester derivatives represented by the general formula: ##STR1## wherein either one of X and Y represents a nitro group, and the other represents ##STR2## in which R represents a lower alkyl group, and n represents a figure of 1-50. The oxalic acid ester derivatives are useful as chemiluminescent reagents for fluororescent substances.
    Type: Grant
    Filed: June 27, 1985
    Date of Patent: March 25, 1986
    Assignee: Wako Pure Chemical Industries Ltd.
    Inventors: Kazuhiro Imai, Hiroshi Ogata, Motoaki Tanaka, Hiroyoshi Nawa, Masami Ishihara