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(11)

EP 0 475 953 A1

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(43) Date of publication: 25.03.1992 Bulletin 1992/13 (21) Application number: 90906758.0 (22) Date of filing: 10.05.1990

(51) International Patent Classification (IPC):  C08K( . ) C01G 23/ 053( . ) C01G 23/ 047( . ) C22B 34/ 12( . ) (86) International application number: PCT/AU1990/000190 (87) International publication number: WO 1990/013614 (15.11.1990 Gazette 1990/26)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB IT LI LU NL SE (30) Priority: 11.05.1989 AU 19890004122 (71) Applicant: WIMMERA INDUSTRIAL MINERALS PTY. LTD. South Melbourne, VIC 3205 (AU)	(72) Inventors: HOLLITT, Michael, John Wimmera Industrial South Melbourne, VIC 3205 (AU) O'BRIEN, Brian, Anthony Chemistry Centre of Bentley, W.A. 6102 (AU) (74) Representative: Jenkins, Peter David, et al  PAGE WHITE & FARRER 54 Doughty Street London WC1N 2LS London WC1N 2LS (GB)