Patents by Inventor Yoshifumi Hirota

Yoshifumi Hirota 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).

  • Polypropylene molding material
    Patent number: 6228951
    Abstract: Disclosed is a polypropylene molding material obtained by the reaction of a crystalline polypropylene resin and a peroxide, said polypropylene molding material having (A) a melt flow rate of 20 to 100 g/10 min and a weight average molecular weight to number average molecular weight ratio of 1.5 to 3.5 as measured by gel-permeation chromatography, (B) a content of hydrocarbons having 20 to 70 carbon atoms of 0.05% by weight or less, (C) a mean elution temperature (T50) of 75 to 120° C. and a degree of variation of elution (&sgr;) of 9 or smaller, and (D) a Q2/Q1 ratio of 0.75 to 0.95, wherein Q1 is a weight average molecular weight to number average molecular weight ratio of said crystalline polypropylene resin as measured by gel-permeation chromatography, and Q2 is a weight average molecular weight to number average molecular weight ratio of said propylene molding material as measured by gel-permeation chromatography.
    Type: Grant
    Filed: August 23, 1999
    Date of Patent: May 8, 2001
    Assignee: Japan Polychem Corporation
    Inventors: Yoshifumi Hirota, Tadashi Sezume