| 摘要 |
PROBLEM TO BE SOLVED: To attain the compatibility of the elimination of a hot offset with the decrease of flickering by specifying the dependence of a heating element on temperature, providing a pressurizing means with a specific thermally insulating layer and specifying the distance from a pressurizing surface to the thermally insulating layer. SOLUTION: The heating element 108 is formed by coating the surface of a substrate consisting of alumina, etc., of a heater 102 with a pasty electric resistance material, such as, for example, Ag/Pd (silver palladium), by screen printing, etc., and firing the coating. This heating element 108 has such dependence on temperature that the calorific value changes according to temperature in such a manner that calorific value is relatively low at a point of a high temperature and is relatively high at a point of low temperature at the time of continuous paper passage of a small-sized recording material. A pressurizing roller 104 is constituted by coating an arbor 104a with an elastic material 104b, such as foamed silicone rubber, and the surface layer 104c is provided with a film of a fluororesin. This pressurizing means has the thermally insulating layer of <=0.3×10-3 [cal/sec cm deg.C] in thermal conductivity and >=2 mm in thickness. The distance from the pressurizing surface to the thermally insulating layer is <=0.2 mm. |
