(19)

(11)

EP 0 547 175 A1

(12)

(43) Date of publication: 23.06.1993 Bulletin 1993/25 (21) Application number: 91918743.0 (22) Date of filing: 05.09.1991

(51) International Patent Classification (IPC):  C22C 21/ 06( . ) C22F 1/ 047( . ) C22F 1/ 04( . ) (86) International application number: PCT/US1991/006374 (87) International publication number: WO 1992/004476 (19.03.1992 Gazette 1992/07)

(84) Designated Contracting States: DE FR GB IT SE (30) Priority: 05.09.1990 US 19900577880 04.09.1991 US 19910754930 (71) Applicant: GOLDEN ALUMINUM COMPANY Golden, CO 80401-1924 (US)	(72) Inventors: MARSH, Ivan, M. Denver, CO 80202 (US) McAULIFFE, Donald, C. Golden, CO 80401 (US) (74) Representative: Wharton, Peter Robert  Urquhart-Dykes & Lord Inventions House Valley Court, Canal Road Bradford BD1 4SP Bradford BD1 4SP (GB)