(19)

(11)

EP 1 339 884 A2

(12)

(88) Date of publication A3: 15.08.2002 (43) Date of publication: 03.09.2003 Bulletin 2003/36 (21) Application number: 01982619.7 (22) Date of filing: 15.11.2001

(51) International Patent Classification (IPC)7: C22B 4/00, C22B 34/12 (86) International application number: PCT/GB0105/031 (87) International publication number: WO 0204/0725 (23.05.2002 Gazette 2002/21)

(84) Designated Contracting States: AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR Designated Extension States: AL LT LV MK RO SI (30) Priority: 15.11.2000 GB 0027929 (71) Applicant: CAMBRIDGE UNIVERSITY TECHNICAL SERVICES LIMITED Cambridge CB2 1TS (GB)	(72) Inventors: FRAY, Derek John,University of Cambridge Cambridge CB2 3QZ (GB) CHEN, George Zheng,University of Cambridge Cambridge CB2 3QZ (GB) (74) Representative: Goodman, Simon John Nye et al Reddie & Grose,16 Theobalds Road London WC1X 8PL London WC1X 8PL (GB)