| 摘要 |
<p>The present invention provides a seamless tubular electrically-semiconductive film excellent in heat resistance, chemical resistance and mechanical property with excellent electrical resistance properties being applied thereto. The seamless tubular electrically-semiconductive film comprises an aromatic polyimide and an electrically-conductive carbon black having a volatile content of 10-25% which consists mainly of volatile acidic ingredients having a pH of not more than 4. Combination of the polyimide having a Tg of 210-350 DEG C and a surface oxidation-treated carbon black is preferred since the combination enables to easily obtain the film wherein a surface resistivity/volume resistivity ratio is not more than two digits, and variation in the surface resistivity caused by an applied voltage for charging is not more than half a digit. The film is produced, for example, by centrifugal casting. The film is remarkably advantageous as an intermediate transfer belt in a color copying machine.</p> |
