Patents by Inventor Gary Michael Freeman

Gary Michael Freeman 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).

  • Precipitated calcium carbonate product having improved brightness and method of preparing the same
    Patent number: 6143065
    Abstract: A method of significantly improving the brightness and shade properties of a high quality PCC product. The method includes providing a calcium containing feed source that contains discoloring impurities. The calcium containing feed source is formed into an aqueous slurry of calcium carbonate. Thereafter, the slurry is fine screened through a 325 mesh screen in order to yield a slurry of filler grade calcium carbonate. The filler grade calcium carbonate slurry is wet milled in order to liberate the discoloring impurities and reduce the median particle size of the calcium carbonate to less than 2 microns. The discoloring impurities are then magnetically separated from the milled calcium carbonate slurry by subjecting the slurry to a high intensity magnetic filed. After the magnetic separation step, the purified slurry may be de-watered to yield a dry powder; or alternatively, the slurry may be retained in aqueous form.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: November 7, 2000
    Assignee: J. M. Huber Corporation
    Inventors: Gary Michael Freeman, John Mecaslin MacGeoghegan Harrison, Klaus A. Lunden