(19)

(11)

EP 1 165 441 A1

(12)

(43) Date of publication: 02.01.2002 Bulletin 2002/01 (21) Application number: 99915098.0 (22) Date of filing: 31.03.1999

(51) International Patent Classification (IPC)7: C01F 11/18 (86) International application number: PCT/US9906/853 (87) International publication number: WO 0058/217 (05.10.2000 Gazette 2000/40)

(84) Designated Contracting States: AT BE DE ES FI FR GB IT NL PT SE (71) Applicant: MINERALS TECHNOLOGIES INC. New York, New York 10174-1901 (US)	(72) Inventors: DEUTSCH, Donald, Richard Walnutport, PA 18088 (US) WISE, Kenneth, James Schnecksville, PA 18078 (US) (74) Representative: Bawden, Peter Charles et al Bawden & Associates, 4 The Gatehouse, 2 High Street Harpenden, Hertfordshire AL5 2TH Harpenden, Hertfordshire AL5 2TH (GB)