Patents by Inventor Hirosi Ohhira

Hirosi Ohhira 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).

  • Polyvinylidene fluoride filaments
    Patent number: 4302556
    Abstract: An improved polyvinylidene fluoride resin-made filament. It consists substantially of a blend of 99-wt. % of a first polyvinylidene fluoride resin component having an inherent viscosity higher than 1.30 dl/g on the one hand, and 1-60 wt. % of a second polyvinylidene fluoride component having an inherent viscosity lower than 1.20 dl/g on the other. The blend has a critical shearing stress lower than 2.8.times.10 dyne/cm.sup.2 and is subjected to melt-spinning and successively to a primary and a secondary stretching in a temperature region of 70.degree.-180.degree. C. The overall stretch factor is selected to be 4-10.
    Type: Grant
    Filed: August 23, 1979
    Date of Patent: November 24, 1981
    Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
    Inventors: Hiroyuki Endo, Hirosi Ohhira, Tohru Sasaki