Patents by Inventor Hirotugu Niwa

Hirotugu Niwa 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).

  • Component of catalyst for olefin polymerization
    Patent number: 6677411
    Abstract: A catalyst component for olefin polymerization, which comprises an ion-exchange layered silicate having the following features 1 and 2: feature 1: in a pore size distribution curve calculated from desorption isotherm by nitrogen adsorption-desorption method, a pore diameter Dm showing a maximum peak intensity DVM is from 60 to 200 Å; and feature 2: in a pore size distribution curve calculated from desorption isotherm by nitrogen adsorption-desorption method, a pore diameter Dm1/2 (Å) on the smaller pore size side corresponding to a ½ peak intensity of the maximum peak intensity DVM has a relation of Dm1/2/Dm of at least 0.65 and less than 1, provided that the largest value is employed when there are a plurality of Dm1/2 values.
    Type: Grant
    Filed: May 6, 2002
    Date of Patent: January 13, 2004
    Assignee: Japan Polychem Corporation
    Inventors: Hideshi Uchino, Hiroshi Nakano, Shuuichi Toriu, Takao Tayano, Hirotugu Niwa, Yoshiyuki Ishihama, Toshihiko Sugano
  • Component of catalyst for olefin polymerization
    Publication number: 20030027950
    Abstract: A catalyst component for olefin polymerization, which comprises an ion-exchange layered silicate having the following features 1 and 2:
    Type: Application
    Filed: May 6, 2002
    Publication date: February 6, 2003
    Inventors: Hideshi Uchino, Hiroshi Nakano, Shuuichi Toriu, Takao Tayano, Hirotugu Niwa, Yoshiyuki Ishihama, Toshihiko Sugano