Patents by Inventor Chris B. Maxwell

Chris B. Maxwell 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).

  • Calcined kaolin clay pigments having improved color and process for the manufacture thereof
    Patent number: 6379452
    Abstract: Calcined kaolin clay pigments having improved color are manufactured by adding a blue agent to the kaolin clay pigment prior to calcination, and then calcining the pigment and blue agent mixture.
    Type: Grant
    Filed: March 23, 2000
    Date of Patent: April 30, 2002
    Assignee: Thiele Kaolin Company
    Inventors: Chris B. Maxwell, Zhenzhong Zhang, Haydn H. Murray
  • Kaolin clay agglomerates and process for the manufacture thereof
    Patent number: 6238473
    Abstract: Kaolin clay agglomerates having improved bulk density, improved rheological properties and good optical properties are provided by mixing calcined kaolin clay, hydrous kaolin clay and water and then subjecting the mixture to high pressure in a compaction system.
    Type: Grant
    Filed: February 3, 1999
    Date of Patent: May 29, 2001
    Assignee: Thiele Kaolin Company
    Inventors: Chris B. Maxwell, Prakash B. Malla
  • Process for beneficiating kaolin clays
    Patent number: 6186335
    Abstract: A improved process for beneficiating kaolin clays to remove discoloring impurities is disclosed. The beneficiation of kaolin clay is improved by fractionating a kaolin clay starting material into a lower brightness first fraction having a majority of the discoloring impurities and a higher brightness second fraction with less impurities. The first fraction is then beneficiated (such as by flotation, selection flocculation, high intensity magnetic separation and/or leaching) to produce a kaolin clay product with improved optical properties. The first and second fractions may be combined to produce a product with improved optical properties.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: February 13, 2001
    Assignee: Thiele Kaolin Company
    Inventors: Lee Ann Arrington-Webb, Robert A. Lowe, Chris B. Maxwell, Prakash B. Malla, Amy C. Semratedu, Cesar I. Basilio
  • Process for improving the brightness of fine-grained kaolin clays
    Patent number: 5810998
    Abstract: Fine-grained kaolin clays having improved brightness can be produced by (a) using centrifugation to fractionate the clay starting material into finer and coarser fractions, (b) subjecting the coarser fraction to flotation to remove discoloring impurities and (c) combining the finer and floated coarser fractions to produce fine-grained kaolin clays having improved brightness.
    Type: Grant
    Filed: June 5, 1997
    Date of Patent: September 22, 1998
    Assignee: Thiele Kaolin Company
    Inventors: Lee Ann Arrington-Webb, Chris B. Maxwell, Prakash B. Malla, Amy C. Semratedu
  • Kaolin-potassium acetate intercalation complex and process of forming same
    Patent number: 5672555
    Abstract: A process for intercalating potassium acetate molecules in kaolin clay particles to achieve delamination has been developed by mixing kaolin clay particles, potassium acetate and water. A maximum intercalation, and hence a maximum degree of delamination, can be achieved with potassium acetate levels between 10% and 75% by weight, based on the weight of kaolin clay particles, and 5% and 50% water by weight, based on the weight of potassium acetate.
    Type: Grant
    Filed: February 29, 1996
    Date of Patent: September 30, 1997
    Assignee: Thiele Kaolin Company
    Inventors: Chris B. Maxwell, Prakash B. Malla
  • Chemically aggregated kaolin clay pigment and process for making the same by phosphate bonding
    Patent number: 5584925
    Abstract: An opacifying kaolin pigment with improved porosity, light scattering ability (opacity), gloss, and ink receptivity over that of the starting pigment is manufactured by a process which comprises the steps of treating an aqueous solution of kaolin with a phosphate compound, using the endogenous aluminum leached from kaolin and/or adding a soluble aluminum compound and increasing the pH of the mixture.
    Type: Grant
    Filed: June 26, 1995
    Date of Patent: December 17, 1996
    Assignee: Thiele Kaolin Company
    Inventors: Chris B. Maxwell, Prakash B. Malla