(19)

(11)

EP 0 502 065 A1

(12)

(43) Date of publication: 09.09.1992 Bulletin 1992/37 (21) Application number: 90917662.0 (22) Date of filing: 27.11.1990

(51) International Patent Classification (IPC):  G01N 23/ 207( . ) G21K 1/ 06( . ) (86) International application number: PCT/GB1990/001840 (87) International publication number: WO 1991/008471 (13.06.1991 Gazette 1991/13)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB IT LI LU NL SE (30) Priority: 29.11.1989 GB 19890026998 (71) Applicant: FISONS plc Ipswich Suffolk IP1 1QH (GB)	(72) Inventors: NEGRO, Pierre-Yves CH-1024 Ecublens (CH) VOGEL, Wilfried CH-1096 Cully (CH) YELLEPEDDI, Ravisekhar CH-1024 Ecublens (CH) (74) Representative: Wright, Robert Gordon McRae  FISONS plc 12 Derby Road Loughborough Leicestershire LE11 0BB Loughborough Leicestershire LE11 0BB (GB)