Patents by Inventor Keh-Chang Liu

Keh-Chang Liu 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).

  • Elongated bendable drainage mat
    Patent number: 4572700
    Abstract: Elongated, bendable drainage mat having a rectangular transverse cross section and comprising a polymeric core having a plurality of substantially rigid fingers extending from one side of a layer and an enveloping water permeable fabric having a permittivity from 0.2 seconds.sup.-1 to 2.0 seconds.sup.-1 and a dynamic permeability after 10.sup.6 loadings of at least 10.sup.-4 centimeters per second.Apparatus and systems using such drainage mat.
    Type: Grant
    Filed: March 31, 1983
    Date of Patent: February 25, 1986
    Assignee: Monsanto Company
    Inventors: Joseph Mantarro, Keh-Chang Liu, Barry J. Dempsey