Patents by Inventor Ronald Windell Andrews

Ronald Windell Andrews 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).

  • Method of treating an aqueous suspension of kaolin
    Patent number: 6615987
    Abstract: A method of treating a kaolin particulate material to improve its properties by removal of impurities which includes the steps of: (a) producing a dispersed aqueous suspension of a kaolin particulate material containing at least 0.1% by weight, based on the dry weight of the kaolin particulate material, of separable impurity by adding a dispersing agent to the kaolin particulate material to deflocculate solid particles of the material in the suspension; (b) conditioning the suspension prior to adding selective flocculation polymer thereto by allowing the suspension to age for a period of at least 30 minutes and optionally by adding one or more conditioning chemicals thereto; (c) adjusting the pH of the suspension to be at least about 9.5; (d) adding to the suspension at a pH of at least about 9.
    Type: Grant
    Filed: May 5, 2000
    Date of Patent: September 9, 2003
    Assignee: Imerys Pigments, Inc.
    Inventors: David Andrew Greenhill, Anthony Allan May, Christopher R. L. Golley, Ronald Windell Andrews