(19)

(11)

EP 0 495 978 A1

(12)

(43) Date of publication: 29.07.1992 Bulletin 1992/31 (21) Application number: 91916653.0 (22) Date of filing: 25.07.1991

(51) International Patent Classification (IPC):  C22F 1/ 18( . ) G21C 3/ 07( . ) G21C 3/ 06( . ) (86) International application number: PCT/US1991/005143 (87) International publication number: WO 1992/002654 (20.02.1992 Gazette 1992/05)

(84) Designated Contracting States: DE FR GB SE (30) Priority: 03.08.1990 US 19900562576 08.07.1991 US 19910726964 (71) Applicant: TELEDYNE INDUSTRIES INC Albany, Oregon 97321 (US)	(72) Inventors: WANG, Chun, T. Salem, OR 97302 (US) McCLANAHAN, Buford, A. Albany, OR 97321 (US) EUCKEN, Craig, M. Scio, OR 97374 (US) (74) Representative: Watts, Peter Graham, et al  Anthony Cundy & Co., 1623 Warwick Road Knowle, Solihull, West Midlands B93 9LF Knowle, Solihull, West Midlands B93 9LF (GB)