(19)

(11)

EP 0 496 734 A1

(12)

(43) Date of publication: 05.08.1992 Bulletin 1992/32 (21) Application number: 90913042.0 (22) Date of filing: 07.08.1990

(51) International Patent Classification (IPC):  D01F 6/ 30( . ) D01F 8/ 06( . ) D01F 8/ 14( . ) D01F 6/ 84( . ) D01F 8/ 12( . ) D04H 1/ 54( . ) (86) International application number: PCT/US1990/004410 (87) International publication number: WO 1992/002669 (20.02.1992 Gazette 1992/05)

(84) Designated Contracting States: BE DE ES FR GB IT NL SE (71) Applicant: THE DOW CHEMICAL COMPANY Midland, Michigan 48640 (US)	(72) Inventors: TABOR, Ricky, L. Lake Jackson, TX 77566 (US) LANCASTER, Gerald, M. Freeport, TX 77541 (US) BIESER, John, O. Lake Jackson, TX 77566 (US) FINLAYSON, Malcolm, F. Houston, TX 77008 (US) (74) Representative: Burford, Anthony Frederick, et al  W.H. Beck, Greener & Co. 7 Stone Buildings Lincoln's Inn London WC2A 3SZ London WC2A 3SZ (GB)