Patents by Inventor Robert Harvey Moffett

Robert Harvey Moffett 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).

  • Modified cationic starch composition for removing particles from aqueous dispersions
    Patent number: 5859128
    Abstract: Modified starches prepared by cooking an amphoteric or cationic starch and an anionic, amphoteric, or cationic polyacrylamide have utility as a retention aid in the manufacture of paper.
    Type: Grant
    Filed: October 30, 1997
    Date of Patent: January 12, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: Robert Harvey Moffett
  • Method for preparing low-concentration polyaluminosilicate microgels
    Patent number: 5853616
    Abstract: An improved method and apparatus for preparing low-concentration polyaluminosilicate microgels from a water soluble silicate and an alkali metal aluminate in which the silicate and the aluminate are mixed at a rate to produce a Reynolds number of at least 4000, the mixture is aged and then diluted to a silica concentration of not more than 1.0 wt. %. The method achieves reduced silica deposition during the preparation of the microgels.
    Type: Grant
    Filed: June 13, 1997
    Date of Patent: December 29, 1998
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Robert Harvey Moffett, John Derek Rushmere
  • Process for preparing water soluble polyaluminosilicates
    Patent number: 5707494
    Abstract: An improved method for the production of water soluble polyaluminosilicate microgels, formed by the reaction of solutions of alkali metal silicates with solutions of acids containing dissolved aluminum compounds, is provided.
    Type: Grant
    Filed: January 6, 1997
    Date of Patent: January 13, 1998
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: John Derek Rushmere, Robert Harvey Moffett
  • Method for preparing low-concentration polyaluminosilicate microgels
    Patent number: 5648055
    Abstract: An improved method and apparatus for preparing low-concentration polyaluminosilicate microgels from a water soluble silicate and a strong acid in which the silicate and acid are mixed at a rate to produce a Reynolds number of at least 4000, the mixture is aged and then diluted to a silica concentration of not more than 1.0 wt. %. The method achieves reduced silica deposition during the preparation of the microgels.
    Type: Grant
    Filed: October 25, 1995
    Date of Patent: July 15, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Robert Harvey Moffett, John Derek Rushmere