(19)

(11)

EP 0 190 153 A1

(12)

(43) Date of publication: 13.08.1986 Bulletin 1986/33 (21) Application number: 85902773.0 (22) Date of filing: 09.05.1985

(51) International Patent Classification (IPC):  C09K 11/ 77( . ) H01J 29/ 20( . ) C09K 11/ 80( . ) (86) International application number: PCT/US1985/000851 (87) International publication number: WO 1986/000633 (30.01.1986 Gazette 1986/03)

(84) Designated Contracting States: DE FR GB NL (30) Priority: 09.07.1984 US 19840629084 (71) Applicant: AT&T Corp. New York, NY 10013-2412 (US)	(72) Inventors: BERKSTRESSER, George, Wayne Bridgewater, NJ 08807 (US) HUO, Tai-Chan, Donald New Providence, NJ 07974 (US) (74) Representative: Johnston, Kenneth Graham, et al  AT&T (UK) Ltd. 5 Mornington Road Woodford Green Essex, IG8 OTU Woodford Green Essex, IG8 OTU (GB)