Abstract: In order to reliably clean a thermal fixing roll for fixing a non-fixed image in an image forming apparatus such as a copier or a laser beam printer, a non-woven fabric web having a crisscross structure or a parallel structure with a thermally bonded fiber sheet is disposed at least on the side in contact with the fixing roll. The thermally bonded fiber sheet comprises composite fibers including 5 to 70% by weight of electroless nickel plated `CONEX` fibers, which is obtained by depositing metallic nickel to a thickness of up to and including 0.2 .mu.m by an electroless plating method on `CONEX` fibers which have the surface formed with stripe-like grooves, macrovoids, fine irregularities or a modified cross-section and is heat-resistant and excellent in adhesion for nickel, in addition to non-plated `CONEX` fibers and undrawn polyester fibers. Preferably, the above non-fabric web is impregnated with a heat-resistant cationic charging agent as a cleaning roll material.