Patents by Inventor Katsumasa Ohtake

Katsumasa Ohtake 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).

  • Method for dyeing hydrophobic fiber material with disperse dye
    Patent number: 4185959
    Abstract: A hydrophobic fiber material is dyed in a dye bath containing at least nine disperse dyes having different chemical structures from one another within a short period of time with a good levelness.
    Type: Grant
    Filed: December 23, 1976
    Date of Patent: January 29, 1980
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Kunihiko Imada, Katsumasa Ohtake, Taizo Ohshima, Sanae Sakaguchi
  • Azo disperse dye mixtures
    Patent number: 3966399
    Abstract: A mixture of at least two members selected from the group consisting of compounds represented by the formula, ##SPC1##Wherein Z represents hydrogen atom or methyl, ethyl, methoxy or ethoxy group, each R.sub.1 and R.sub.2 represents methyl or ethyl group, R.sub.3 represents methyl, ethyl or phenyl group or a phenyl group substituted by methyl, ethyl, methoxy or ethoxy group. The mixture is useful for dyeing hydrophobic fibers such as polyester fibers, and has good dyeabilities, particularly, build-up property.
    Type: Grant
    Filed: April 9, 1973
    Date of Patent: June 29, 1976
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Katsunobu Sato, Yoshihisa Sueda, Yoshiro Izutsutani, Kunihiko Imada, Katsumasa Ohtake