(19)

(11)

EP 0 411 047 A1

(12)

(43) Date of publication: 06.02.1991 Bulletin 1991/06 (21) Application number: 89905920.0 (22) Date of filing: 18.04.1989

(51) International Patent Classification (IPC):  C01B 13/ 14( . ) C01G 3/ 00( . ) C04B 35/ 65( . ) H01L 39/ 24( . ) C01G 1/ 00( . ) C04B 35/ 45( . ) C25D 5/ 50( . ) (86) International application number: PCT/US1989/001623 (87) International publication number: WO 1989/010336 (02.11.1989 Gazette 1989/26)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 29.04.1988 US 19880188019 29.04.1988 US 19880188772 (71) Applicant: AlliedSignal Inc. Morristown, New Jersey 07962-2245 (US)	(72) Inventors: MAXFIELD, MacRae Plainfield, NJ 07062 (US) BAUGHMAN, Ray, H. Morris Plains, NJ 07950 (US) IGBAL, Zafar Morristown, NJ 07960 (US) ECKHARDT, Helmut Madison, NJ 07940 (US) (74) Representative: Brock, Peter William  Urquhart-Dykes & Lord 1 Richfield Place Richfield Avenue Reading RG1 8EQ Berkshire Reading RG1 8EQ Berkshire (GB)