| 摘要 |
PURPOSE:To improve an oil holding capacity of the surface of a roller, and to execute stably a prevention of an offset by setting a surface roughness of the roller within a prescribed range. CONSTITUTION:As a surface roughness Ra becomes small and a roller becomes smooth, an oil applying quantity to the surface of the roller is decreased and a parting property to a toner is lowered, and an offset is apt to be generated. Especially, it is remarkable, in case Ra is <=0.04mum. In case the surface roughness Ra is >=0.4mum, the uniformity of the surface of the roller is bad and the surface becomes rough, therefore, the roughness of the roller appears on the surface of a toner image supporting body after the fixation and the quality of a copy is deteriorated. Accordingly, it is necessary that the surface roughness Ra of a pair of rollers 2, 6 is within 0.05-0.3mum, and it is desirable that it is within a range of 0.07-0.2mum. |
