(19)

(11)

EP 0 429 446 A1

(12)

(43) Date of publication: 05.06.1991 Bulletin 1991/23 (21) Application number: 89900031.0 (22) Date of filing: 21.11.1988

(51) International Patent Classification (IPC):  B65H 63/ 06( . ) G01N 29/ 04( . ) G01H 1/ 04( . ) G01N 29/ 22( . ) (86) International application number: PCT/US1988/004174 (87) International publication number: WO 1989/004960 (01.06.1989 Gazette 1989/12)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 20.11.1987 US 19870122763 (71) Applicant: SOUTHWEST RESEARCH INSTITUTE San Antonio, TX 78284 (US)	(72) Inventors: KWUN, Hegeon San Antonio, TX 78284 (US) BURKHARDT, Gary, L. San Antonio, TX 78284 (US) (74) Representative: Horner, Martin Grenville, et al  Cruikshank & Fairweather 19 Royal Exchange Square Glasgow G1 3AE Scotland Glasgow G1 3AE Scotland (GB)