(19)

(11)

EP 0 921 856 A1

(12)

(43) Date of publication: 16.06.1999 Bulletin 1999/24 (21) Application number: 97935690.0 (22) Date of filing: 08.08.1997

(51) International Patent Classification (IPC):  B01J 23/ 94( . ) C07C 51/ 42( . ) C07C 63/ 26( . ) B01J 38/ 68( . ) C07C 51/ 50( . ) (86) International application number: PCT/GB1997/002158 (87) International publication number: WO 1998/008605 (05.03.1998 Gazette 1998/09)

(84) Designated Contracting States: BE DE FR GB IT NL (30) Priority: 29.08.1996 GB 19960017995 29.08.1996 GB 19960017996 29.08.1996 GB 19960017997 29.08.1996 GB 19960017998 09.12.1996 US 19960033272P 09.12.1996 US 19960033273P 09.12.1996 US 19960033275P 09.12.1996 US 19960033277P (60) Divisional application: 02078345.2 / 1281438 (71) Applicant: E.I. DU PONT DE NEMOURS AND COMPANY Wilmington Delaware 19898 (US)

(72) Inventors: JEFFERY, Ian, Charles Cleveland TS20 1LP (GB) WHISTON, Keith County Durham DL3 8EY (GB) (74) Representative: Jones, Alan John  CARPMAELS & RANSFORD 43 Bloomsbury Square London, WC1A 2RA London, WC1A 2RA (GB)