(19)

(11)

EP 0 490 978 A1

(12)

(43) Date of publication: 24.06.1992 Bulletin 1992/26 (21) Application number: 90914002.0 (22) Date of filing: 04.09.1990

(51) International Patent Classification (IPC):  C01B 11/ 12( . ) (86) International application number: PCT/US1990/005008 (87) International publication number: WO 1991/003421 (21.03.1991 Gazette 1991/07)

(84) Designated Contracting States: DK GB SE (30) Priority: 05.09.1989 US 19890403279 13.07.1990 US 19900552282 (71) Applicant: OLIN CORPORATION Cheshire, CT 06410-0586 (US)	(72) Inventors: DUNCAN, Budd, L. Athens, TN 37303 (US) GEREN, George, W. Georgetown, TN 37336 (US) LEONARD, Donald, R. Athens, TN 37303 (US) (74) Representative: Blatchford, William Charles, et al  WITHERS & ROGERS 4 Dyers Buildings Holborn London, EC1N 2JT London, EC1N 2JT (GB)