Patents by Inventor Peter B. O'Rorke

Peter B. O'Rorke 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 for the production of precipitated calcium carbonate having a selected crystal form, products produced thereby and their uses
    Patent number: 6221146
    Abstract: A method of producing a precipitated calcium carbonate (pcc) product which has a coarse crystalline form which comprises the steps of: (a) preparing a suspension in an aqueous medium of calcium hydroxide particles which partially dissolve as calcium ions in the aqueous medium, the aqueous medium also incorporating an agent which promotes release into solution in the aqueous medium of calcium ions from the calcium hydroxide; (b) adding carbon dioxide to the aqueous medium to react with the calcium ions therein to produce a suspension in the aqueous medium of a precipitate of calcium carbonate crystals; (c) concentrating the suspension of the precipitate by a dewatering process; and (d) adding to the suspension of the precipitate a dispersing agent for the precipitate; wherein in step (a) the calcium hydroxide particles of the suspension of calcium hydroxide particles have a specific surface area measured by the BET nitrogen method of less than 33 m2/g and the said agent comprises a water soluble organic c
    Type: Grant
    Filed: April 1, 1999
    Date of Patent: April 24, 2001
    Assignee: Imerys Pigments, Inc.
    Inventors: Steven M. Fortier, William B. Jackson, Peter B. O'Rorke, Ricardo Perez, David P. Bryan