(19)

(11)

EP 0 069 772 A1

(12)

(43) Date of publication: 19.01.1983 Bulletin 1983/03 (21) Application number: 82900710.0 (22) Date of filing: 15.01.1982

(51) International Patent Classification (IPC):  C25B 13/ 00( . ) (86) International application number: PCT/US1982/000040 (87) International publication number: WO 1982/002564 (05.08.1982 Gazette 1982/19)

(84) Designated Contracting States: BE DE FR GB NL (30) Priority: 16.01.1981 US 19810225651 (71) Applicant: E.I. DU PONT DE NEMOURS AND COMPANY Wilmington Delaware 19898 (US)	(72) Inventors: BISSOT, Thomas Charles Newark, DE 19711 (US) SILVA, Raimund Heinrich D-3101 Winsen (DE) (74) Representative: Abitz, Walter, Dr.-Ing., et al  Patentanwälte Abitz & Partner Postfach 86 01 09 D-81628 München D-81628 München (DE)