(19)

(11)

EP 0 646 228 A1

(12)

(43) Date of publication: 05.04.1995 Bulletin 1995/14 (21) Application number: 93913282.0 (22) Date of filing: 03.06.1993

(51) International Patent Classification (IPC):  F23C 13/ 00( . ) F23R 3/ 46( . ) F23R 3/ 40( . ) (86) International application number: PCT/GB1993/001177 (87) International publication number: WO 1993/025852 (23.12.1993 Gazette 1993/30)

(84) Designated Contracting States: BE DE FR GB IT NL SE (30) Priority: 16.06.1992 GB 19920012794 (71) Applicant: IMPERIAL CHEMICAL INDUSTRIES PLC London SW1P 3JF (GB)	(72) Inventors: FOWLES, Martin Danby, North Yorkshire YO21 2JQ (GB) LYWOOD, Warwick John Yarm, Cleveland TS15 0JT (GB) SHIPLEY, David Graham Yarm, Cleveland TS15 9JZ (GB) (74) Representative: Gratwick, Christopher, et al  Intellectual Property Department ICI Chemicals & Polymers Ltd P.O. Box 11 The Heath Runcorn Cheshire WA7 4QE Runcorn Cheshire WA7 4QE (GB)