To prevent unevenness in resistance by composing a semiconductor layer by including resin-coated carbon black in a synthetic resin as one surface layer, and a semiconductor layer prepared by blending carbon black not coated with the resin in a synthetic resin, as at least another layer.
A material, mainly composed of polybutylene terephthalate(PBT), is kneaded by an extruder to obtain the pellet. The pellet including the carbon black not coated with the resin, is used in the extruder at an inner layer side, and the pellet including the resin coated-carbon black is used in the extruder at an outer layer side. A multilayer seamless belt of 160 mm diameter and 300 mm length is obtained from an extruded molten tube. The thickness of one surface semiconductive layer is 40 μm, and that of a supporting semiconductor layer is 110 μm. The minimum value of the volume resistance in 20-points measurement of the obtained multilayer seamless belt is 2.2×109 Ω.cm, the maximum value is 9.2×109 Ω.cm, and the average is 4.7×109 Ω.cm. This multilayer seamless belt is used as an intermediate transfer belt 6.
HISA HIDEYUKI
MORIKOSHI MAKOTO
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