(19)

(11)

EP 0 325 653 A1

(12)

(43) Date of publication: 02.08.1989 Bulletin 1989/31 (21) Application number: 88908464.0 (22) Date of filing: 26.07.1988

(51) International Patent Classification (IPC):  C01G 23/ 04( . ) C01G 23/ 053( . ) C23C 20/ 08( . ) B01D 71/ 02( . ) C04B 35/ 46( . ) (86) International application number: PCT/US1988/002537 (87) International publication number: WO 1989/000983 (09.02.1989 Gazette 1989/04)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 27.07.1987 US 19870077799 (71) Applicant: WISCONSIN ALUMNI RESEARCH FOUNDATION Madison, WI 53707 (US)	(72) Inventors: ANDERSON, Marc, A. Madison, WI 53705 (US) XU, Qunyin Madison, WI 53705 (US) (74) Representative: Ellis-Jones, Patrick George Armine  J.A. KEMP & CO. 14 South Square Gray's Inn London WC1R 5LX London WC1R 5LX (GB)