(19)

(11)

EP 0 447 538 A1

(12)

(43) Date of publication: 25.09.1991 Bulletin 1991/39 (21) Application number: 90915893.0 (22) Date of filing: 10.10.1990

(51) International Patent Classification (IPC):  A62D 1/ 00( . ) A62D 1/ 08( . ) (86) International application number: PCT/US1990/005778 (87) International publication number: WO 1991/005585 (02.05.1991 Gazette 1991/10)

(84) Designated Contracting States: AT BE DE DK ES FR GR IT NL (30) Priority: 10.10.1989 US 19890419132 21.11.1989 US 19890439738 02.03.1990 US 19900488295 01.08.1990 US 19900561690 (71) Applicant: Great Lakes Chemical Corporation West Lafayette, IN 47906 (US)	(72) Inventors: IIKUBO, Yuichi West Lafayette, IN 47906 (US) ROBIN, Mark, Lester West Lafayette, IN 47906 (US) FIDELLE, Thomas, P. Lafayette, IN 47905 (US) ROSE, Richard, S. West Lafayette, IN 47906 (US) SWEVAL, Mark, A. Lafayette, IN 47905 (US) (74) Representative: Bond, Bentley George, et al  Haseltine Lake & Co. 28 Southampton Buildings Chancery Lane London WC2A 1AT London WC2A 1AT (GB)