(19)

(11)

EP 0 033 334 A1

(12)

(43) Date of publication: 12.08.1981 Bulletin 1981/32 (21) Application number: 80901602.0 (22) Date of filing: 22.07.1980

(51) International Patent Classification (IPC):  G06F 9/ 00( . ) C09B 1/ 62( . ) G02F 1/ 1335( . ) G02F 1/ 139( . ) C09B 1/ 32( . ) C09K 19/ 60( . ) G02F 1/ 137( . ) (86) International application number: PCT/US1980/000913 (87) International publication number: WO 1981/000463 (19.02.1981 Gazette 1981/05)

(84) Designated Contracting States: CH DE FR GB LI (30) Priority: 27.07.1979 US 19790061286 (71) Applicant: MINNESOTA MINING AND MANUFACTURING COMPANY St. Paul, Minnesota 55133-3427 (US)	(72) Inventors: CHERN, Mao-Jin St. Paul, MN 55133 (US) HUFFMAN, William A. St. Paul, MN 55133 (US) NOVACK, James C. St. Paul, MN 55133 (US) (74) Representative: Baillie, Iain Cameron, et al  c/o Ladas & Parry Isartorplatz 5 D-8000 München 2 D-8000 München 2 (DE)