Patents by Inventor John C. Harrington, IV

John C. Harrington, IV 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).

  • Use of polymers in the recycled fiber washing/deinking process
    Patent number: 5626718
    Abstract: The present invention is directed to a method for increasing the retention on a washing/thickening device in an aqueous papermaking system. The method generally comprises adding to the furnish solids of the system an effective amount of a cationic polyacrylamide polymer.
    Type: Grant
    Filed: September 16, 1994
    Date of Patent: May 6, 1997
    Assignee: Betz Laboratories, Inc.
    Inventors: Irenee J. Philippe, Frank J. Sutman, Thomas E. Taggart, Mary B. K. Letscher, Michael A. Schuster, John C. Harrington, IV
  • Method for improving retention and drainage characteristics in alkaline papermaking
    Patent number: 5532308
    Abstract: A composition and method for improving the drainage and retention characteristics of a paper furnish consisting of a water soluble graft copolymer and bentonite clay. It is preferred that the graft copolymer be added to the furnish prior to at least one shear stage and that the bentonite clay be added after the shear stage.
    Type: Grant
    Filed: January 17, 1995
    Date of Patent: July 2, 1996
    Assignee: Betz PaperChem, Inc.
    Inventors: Michael A. Schuster, John C. Harrington, IV, Wen P. Liao, Fu Chen
  • Method for improving retention and drainage characteristics in alkaline papermaking
    Patent number: 5482595
    Abstract: A method of improving the drainage characteristics of a pulp slurry in a papermaking operation utilizing the sequential steps of adding alum, ionic polyacrylamide and cationic starch. The cationic starch can be added to the slurry prior to or after the primary screen.
    Type: Grant
    Filed: March 22, 1994
    Date of Patent: January 9, 1996
    Assignee: Betz PaperChem, Inc.
    Inventors: John C. Harrington, IV, Michael A. Schuster
  • Method for improving retention and drainage characteristics in alkaline papermaking
    Patent number: 5415740
    Abstract: A composition and method for improving the drainage and retention characteristics of a paper furnish consisting of a water soluble graft copolymer and bentonite clay. It is preferred that the graft copolymer be added to the furnish prior to at least one shear stage and that the bentonite clay be added after the shear stage.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: May 16, 1995
    Assignee: Betz PaperChem, Inc.
    Inventors: Michael A. Schuster, John C. Harrington, IV, Wen P. Liao, Fu Chen
  • Quaternized polyvinylamines for deinking loop clarification
    Patent number: 5269942
    Abstract: The use of quaternized polyvinylamine for use in clarification of water in a deinking loop of a paper, such as newspaper, recycling operation.
    Type: Grant
    Filed: January 4, 1993
    Date of Patent: December 14, 1993
    Assignee: Betz Laboratories
    Inventors: John C. Harrington, IV, Jen-Chi Chen, Fu Chen