| 摘要 |
PURPOSE:To inexpensively produce the offset preventive oil by consisting the oil of a specific compd. and cutting off the components of the specific lower limit average mol. wt. or below. CONSTITUTION:A coating layer consisting of fluorine high-polymer compds., such as PTFE and PFE, is provided on the surface of a heat fixing roller 1. An oil applying roller 4 is formed of a silicone sponge roller, felt roller, etc., and applies the offset preventive oil 5 impregnated therein on the surface of the heat fixing roller 1. This offset preventive oil 5 is expressed by formula, where the ratio of (n) and (m) is 10 to 60:1. In addition, the components below the lower limit average mol. wt. expressed by {(23.8Xthe max. heating part temp.)-622} with respect to the max. heating part temp. of the heat fixing roller 1 are cut off. The lower limit average mol. wt. of the fluorine oil which does not evaporate even at the max. heating part temp. is known if the max. heating part temp. attained by the heat fixing roller 1 is known. |
