(19)

(11)

EP 0 455 667 A1

(12)

(43) Date of publication: 13.11.1991 Bulletin 1991/46 (21) Application number: 90901863.0 (22) Date of filing: 25.01.1990

(51) International Patent Classification (IPC):  C12N 9/ 10( . ) C12N 15/ 82( . ) C12N 15/ 54( . ) (86) International application number: PCT/GB1990/000101 (87) International publication number: WO 1990/008826 (09.08.1990 Gazette 1990/19)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IT LI LU NL SE (30) Priority: 26.01.1989 GB 19890001673 (71) Applicant: IMPERIAL CHEMICAL INDUSTRIES PLC London SW1P 3JF (GB)

(72) Inventors: BRIDGES, Ian, Georges Slater, IA 50244 (US) BRIGHT, Simon, William, Jonathan 24 Pound Lane Bucks SL7 2AY (GB) GREENLAND, Andrew, James "The Cabin" Berkshire SL6 8SX (GB) SCHUCH, Wolfgang, Walter 14 Greenfinch Close Berkshire RG11 6TZ (GB) (74) Representative: Huskisson, Frank Mackie, 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)