(19)

(11)

EP 0 446 266 A1

(12)

(43) Date of publication: 18.09.1991 Bulletin 1991/38 (21) Application number: 90900277.0 (22) Date of filing: 01.12.1989

(51) International Patent Classification (IPC):  A01N( . ) A01N 31/ 02( . ) A61L 2/ 00( . ) C07C 47/ 02( . ) C09K 8/ 60( . ) A01N 35/ 02( . ) A01N 41/ 04( . ) C02F 1/ 50( . ) C07C 47/ 12( . ) (86) International application number: PCT/GB1989/001436 (87) International publication number: WO 1990/006054 (14.06.1990 Gazette 1990/14)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 02.12.1988 GB 19880028246 (71) Applicant: NATIONAL RESEARCH DEVELOPMENT CORPORATION London SE1 6BU (GB)	(72) Inventor: WRENCH, Eric Witton Chemical Company Limited Bury St. Edmunds Suffolk IP28 7AY (GB) (74) Representative: Marsh, Roy David  Urquhart-Dykes & Lord Midsummer House 411C Midsummer Boulevard Central Milton Keynes MK9 3BN Central Milton Keynes MK9 3BN (GB)