(19)

(11)

EP 0 493 422 A1

(12)

(43) Date of publication: 08.07.1992 Bulletin 1992/28 (21) Application number: 90913446.0 (22) Date of filing: 17.09.1990

(51) International Patent Classification (IPC):  D21B 1/ 14( . ) D21C 7/ 06( . ) D21B 1/ 22( . ) (86) International application number: PCT/CA1990/000298 (87) International publication number: WO 1991/004371 (04.04.1991 Gazette 1991/08)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB IT LI LU NL SE (30) Priority: 19.09.1989 CA 19890612010 (71) Applicant: HYMAC LTEE LTD. Laval, Quebec H7L 3S4 (CA)	(72) Inventor: ECCLESTON, John R.R. 2 Carvel, Alberta T0E 0H0 (CA) (74) Representative: Strehl Schübel-Hopf Groening & Partner  Maximilianstrasse 54 D-80538 München D-80538 München (DE)