(19)

(11)

EP 0 493 556 A1

(12)

(43) Date of publication: 08.07.1992 Bulletin 1992/28 (21) Application number: 91912808.0 (22) Date of filing: 09.07.1991

(51) International Patent Classification (IPC):  A01N 43/ 50( . ) A01N 43/ 78( . ) A01N 43/ 52( . ) (86) International application number: PCT/EP1991/001293 (87) International publication number: WO 1992/001380 (06.02.1992 Gazette 1992/04)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IT LI LU NL SE (30) Priority: 18.07.1990 GB 19900015786 (71) Applicant: IMPERIAL CHEMICAL INDUSTRIES PLC London SW1P 3JF (GB)	(72) Inventor: EASTWOOD, Ian, Michael 23 Turnpike New Church Lancs BB4 9DU (GB) (74) Representative: Pugsley, Roger Graham, et al  ICI Group Patents Services Dept. PO Box 6 Shire Park Bessemer Road Welwyn Garden City Herts, AL7 1HD Welwyn Garden City Herts, AL7 1HD (GB)