(19)

(11)

EP 0 394 348 A1

(12)

(43) Date of publication: 31.10.1990 Bulletin 1990/44 (21) Application number: 89901660.0 (22) Date of filing: 22.12.1988

(51) International Patent Classification (IPC):  G06T 7/ 00( . ) G06K 9/ 74( . ) G01N 21/ 956( . ) (86) International application number: PCT/US1988/004636 (87) International publication number: WO 1989/006020 (29.06.1989 Gazette 1989/14)

(84) Designated Contracting States: CH DE FR GB IT LI SE (30) Priority: 23.12.1987 US 19870137417 (71) Applicant: E.I. DU PONT DE NEMOURS AND COMPANY Wilmington Delaware 19898 (US)	(72) Inventors: HEKKER, Roeland, M., T. Fairfield, IA 52556 (US) LIVNY, Izhak, M. Fairfield, IA 52556 (US) HARAN, Terence, M. Fairfield, IA 52556 (US) BUCK, Robert, D. Fairfield, IA 52556 (US) (74) Representative: Warren, Keith Stanley  BARON & WARREN 18 South End Kensington London W8 5BU London W8 5BU (GB)