(19)

(11)

EP 0 925 385 A1

(12)

(43) Date of publication: 30.06.1999 Bulletin 1999/26 (21) Application number: 97939102.0 (22) Date of filing: 12.09.1997

(51) International Patent Classification (IPC):  C23C 22/ 50( . ) C23C 22/ 56( . ) C23C 22/ 53( . ) C23C 22/ 68( . ) (86) International application number: PCT/GB1997/002495 (87) International publication number: WO 1998/011274 (19.03.1998 Gazette 1998/11)

(84) Designated Contracting States: AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 13.09.1996 GB 19960019148 (71) Applicant: BRITISH STEEL PLC London NW1 5JD (GB)	(72) Inventors: BAIRD, Amanda, Jane Cardiff CF3 7JX (GB) JEFFS, Brian, David Bridgend CF31 2NP (GB) EDWARDS, Peter, Gerald South Glamorgan CF64 3DE (GB) GOODWIN, Terence, John Porthcawl CF36 3TL (GB) (74) Representative: Downing, Michael Philip, et al  Fry Heath & Spence, The Old College, 53 High Street Horley, Surrey RH6 7BN Horley, Surrey RH6 7BN (GB)