Patents by Inventor Katsumasa Okawa

Katsumasa Okawa 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: 4863504
    Abstract: Novel cyclohexane-1,3-dione derivatives represented by 2-{1-(3-chloro-2-propenyloxyimino)propyl}-5-(1-methyl-1H-pyrazol-4-yl)cycl ohexane-1,3-dione and intermediates thereof are disclosed. The cyclohexane-1,3-dione derivatives have a potent herbicidal effect against a wide variety of weeds and can selectively control injurous weeds at lower dosages. A process for preparing the cyclohexane-1,3-dione derivatives is also disclosed.
    Type: Grant
    Filed: April 26, 1988
    Date of Patent: September 5, 1989
    Assignee: Nihon Nohyaku Co., Ltd.
    Inventors: Hiroshi Hamaguchi, Tetsuji Ohshima, Eiji Kohno, Hideo Takaishi, Tsutomu Mabuchi, Katsumasa Okawa
  • Patent number: 4398943
    Abstract: There is provided a new herbicidal compound of the formula, ##STR1## wherein R.sup.1 is an alkyl group; R.sup.2 is an alkynyl group, a halomethyl group, or a haloethyl group; and X is an alkoxy group, an alkenyloxy group, an alkoxy-alkoxy group, an alkynyloxy group, a hydroxy group, a halomethyloxy group, or a haloethyloxy group.
    Type: Grant
    Filed: December 15, 1981
    Date of Patent: August 16, 1983
    Assignee: Nikon Nohyaku Co., Ltd.
    Inventors: Mitsuru Kajioka, Katsumasa Okawa, Kuniaki Taninaka
  • Patent number: 4334914
    Abstract: Novel benzoate derivatives having a powerful herbicidal effect on various weeds grown in paddy fields, upland fields, and other places have been found out, which are represented by the formula ##STR1## wherein X is --SR, --O--CH.sub.2 CH.sub.2 O).sub.n R, --OCH.sub.2 CH.sub.2 SR, ##STR2## herein R being lower alkyl and n being an integer of 1 to 3.
    Type: Grant
    Filed: February 12, 1981
    Date of Patent: June 15, 1982
    Assignee: Nihon Nohyaku Co., Ltd.
    Inventors: Kunikazu Hiraga, Katsumasa Okawa, Kenichi Ikeda, Masanori Hikawa
  • Patent number: 4318731
    Abstract: A novel .DELTA..sup.2 -1,2,4-triazolin-5-one derivative having a herbicidal activity, which is represented by the formula ##STR1## wherein, R.sup.1 is a C.sub.1 -C.sub.4 alkyl; R.sup.2 is a hydrogen atom, a C.sub.1 -C.sub.6 alkyl group, or a C.sub.2 -C.sub.4 alkenyl group; and X is a hydroxy group, a C.sub.1 -C.sub.4 alkyl group, a C.sub.1 -C.sub.6 alkyloxy group, an alkyloxyalkyloxy group of which two alkyls may be same as or different from each other and each alkyl is of C.sub.1 -C.sub.4, a C.sub.2 -C.sub.4 alkenyloxy, or an alkyloxycarbonylalkyloxy group of which two alkyls may be same as or different from each other and each alkyl is of C.sub.1 -C.sub.4.
    Type: Grant
    Filed: June 24, 1980
    Date of Patent: March 9, 1982
    Assignee: Nihon Nohyaku Co., Ltd.
    Inventors: Mitsuru Kajioka, Hitoshi Kurono, Katsumasa Okawa, Tatsuo Harada