(19)

(11)

EP 0 452 471 A1

(12)

(43) Date of publication: 23.10.1991 Bulletin 1991/43 (21) Application number: 90917257.0 (22) Date of filing: 06.11.1990

(51) International Patent Classification (IPC):  C25D 3/ 04( . ) C25D 21/ 14( . ) (86) International application number: PCT/US1990/006422 (87) International publication number: WO 1991/006693 (16.05.1991 Gazette 1991/11)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 06.11.1989 US 19890431963 (71) Applicant: ATOCHEM NORTH AMERICA, INC. Philadelphia, Pennsylvania 19102 (US)	(72) Inventor: NEWBY, Kenneth, Russ Berkeley Heights, NJ 07922 (US) (74) Representative: Stoner, Gerard Patrick, et al  MEWBURN ELLIS York House 23 Kingsway London WC2B 6HP London WC2B 6HP (GB)