Patents by Inventor Martin C. Riddell

Martin C. Riddell 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).

  • Paper manufacture employing filler and acrylamide polymer conglomerates
    Patent number: 4181567
    Abstract: A method of increasing the amount of mineral filler which can be contained in filled paper sheet produced on a papermaking machine without consequentially reducing the mechanical properties such as the tensile strength of the paper sheet comprises incorporating the mineral filler into the paper pulp furnish, before the latter is transferred to the wire, in the form of a filler/polymer conglomerate formed by contacting the mineral filler with a relatively high molecular weight polymer having a zeta potential in the range of from -40 to +40 electron volts.
    Type: Grant
    Filed: November 11, 1977
    Date of Patent: January 1, 1980
    Assignee: Martin Clark Riddell
    Inventors: Martin C. Riddell, Ian M. Waring