(19)

(11)

EP 0 594 617 A1

(12)

(43) Date of publication: 04.05.1994 Bulletin 1994/18 (21) Application number: 91911773.0 (22) Date of filing: 12.07.1991

(51) International Patent Classification (IPC):  D21F 1/ 00( . ) D21F 7/ 08( . ) (86) International application number: PCT/CA1991/000247 (87) International publication number: WO 1993/001350 (21.01.1993 Gazette 1993/03)

(84) Designated Contracting States: AT DE FR GB IT SE (71) Applicant: JWI LIMITED Kanata Ontario K2K 1X2 (CA)	(72) Inventor: JACKSON, Graham, William Carleton Place, Ontario K7C 3P2 (CA) (74) Representative: Dipl.-Phys.Dr. Manitz Dipl.-Ing. Finsterwald Dipl.-Ing. Grämkow Dipl.-Chem.Dr. Heyn Dipl.-Phys. Rotermund Morgan B.Sc.(Phys.)  Robert-Koch-Strasse 1 D-80538 München D-80538 München (DE)