(19)

(11)

EP 0 440 717 A1

(12)

(43) Date of publication: 14.08.1991 Bulletin 1991/33 (21) Application number: 89912266.0 (22) Date of filing: 25.10.1989

(51) International Patent Classification (IPC):  C08B 37/ 08( . ) (86) International application number: PCT/GB1989/001274 (87) International publication number: WO 1990/004608 (03.05.1990 Gazette 1990/10)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 25.10.1988 GB 19880024971 (71) Applicant: RHONE-POULENC CHEMICALS LIMITED London SW1P 1LS (GB)	(72) Inventor: ROBERTS, George Andrew Francis Southwell, Notts NG25 OAG (GB) (74) Representative: Collier, Jeremy Austin Grey, et al  J.A.KEMP & CO. 14 South Square Gray's Inn London WC1R 5LX London WC1R 5LX (GB)