METHOD FOR FIXING TONER

摘要

PROBLEM TO BE SOLVED: To prevent an offset from occurring even if the surface of a heating roll is not coated with a releasing oil by using a specified copolymer as the material of a releasing layer of the heating roll and a specified polymer as a resin binder of a toner. SOLUTION: The releasing layer 1a of a heating roll 1 in a fixing device is made of a tetrafluoroethylene-perfluoroalkylvinyl ether copolymer and the binder resin of a toner is a polymer containing at least styrene and an alkyl (meth)acrylate as copolymerizable components. The alkyl (metha)acrylate is preferably n-butyl (meth)acrylate. The glass transition temperature of the polymer is <=70 deg.C and the heighest peak molecular weight measured by gel permeation chromatography is 10,000-120,000 (expressed in terms of polystyrene). The polymer does not contain a polyfunctional vinyl compound as a copolymerizable component or contains <=5 wt.% of the compound.