The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 03, 2017
Filed:
Aug. 08, 2014
Omya International Ag, Oftringen, CH;
Marc Maurer, Village-Neuf, FR;
Thomas Schlotterbach, Villach-St. Magdalen, AT;
Mathieu Skrzypczak, Terrace Park, OH (US);
Robert Pirker, Bleiberg-Kreuth, AT;
Omya International AG, Oftringen, CH;
Abstract
The present invention provides a process for preparing a precipitated calcium carbonate product comprising the steps of: (a) preparing an aqueous suspension of precipitated calcium carbonate seeds by carbonating a suspension of Ca(OH)in the presence of 0.005 to 0.030 moles of Sr, in the form of Sr(OH), per mole of Ca(OH), (b) dewatering and dispersing the precipitated calcium carbonate seeds prepared in step (a) to obtain an aqueous suspension of precipitated calcium carbonate seeds having a dof less than or equal to 0.1 to 0.3 μm and a BET specific surface area of 10 to 30 m/g, and (c) forming an aqueous suspension of a precipitated calcium carbonate product by carbonating a slurry of Ca(OH)in the presence of 0.5 to 5% by dry weight of the precipitated calcium carbonate seeds obtained in step (b), wherein the precipitated calcium carbonate seeds have a dthat is less than the dof the precipitated calcium carbonate product and the precipitated calcium carbonate seeds have an aragonitic polymorph content greater than or equal to the precipitated calcium carbonate product obtained in step (c) characterized in that the dewatering of step (b) is carried out by the use of a tube press.