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. 28, 2008
Filed:
Aug. 17, 2001
Philip Kenneth Johns, Cornwall, GB;
David Leslie Light, Cornwall, GB;
Philip Kenneth Johns, Cornwall, GB;
David Leslie Light, Cornwall, GB;
Imerys Minerals Limited, Par Cornwall, GB;
Abstract
There is provided a method of producing a kaolin particulate material suitable for use as an improved super-calendered filler. This method includes: (a) preparing an aqueous feed suspension of kaolin; (b) treating the kaolin of the feed suspension by attrition grinding in a vessel using grinding media granules; (c) delivering an aqueous suspension of the kaolin ground in (b) to a particle size classifier and separating the kaolin of the suspension into a coarse fraction and a fine fraction; (d) returning an aqueous suspension of the coarse fraction produced in (c) to the grinding vessel to be further attrition ground; and (e) extracting an aqueous suspension of the fine fraction produced in (c) as a product suspension. Advantageously, the kaolin of the feed suspension in (a) is such that not more than 30% by weight has a particle size less than 2 μm and not more than 30% by weight has a particle size greater than 10 μm. In addition, the kaolin of the product suspension produced in (e) is such that not more than 10% by weight has a particle size greater than 10 μm and not more than 10% by weight has a particle size less than 0.25 μm.