| 摘要 |
PURPOSE:To uniformize volume resistivity and to stabilize it by forming a cylindrical sleeve for constituting an electrically conductive roll with a hardened resin obtained by incorporating a component A specified in size and a component B smaller in size than A each in a specified range of proportion in an insulating polymer. CONSTITUTION:One hundred pts.wt. of the polymer, such as a phenol resin is mixed with 20-300pts.wt., of carbon powder, and components A and B as reinforcing materials, such as glass fiber, specified each in diameter d and length l as follows; in the case of A, 5mum<=d<=100mum, 1mm<=l<=12mm in the case of B, 0.1mum<=d<=10mum, 0.5mum<=l<=100mum and the contents (wt.%) of A and B are as follows; 5<=A<=45, 2<=B<=35, and 10<=(A+B)<=55, thus permitting the volume resistivity of the cylindrical sleeve not to change with the lapse of time, and partial scattering not to occur, and high-quality copied images to be obtained by using the hardened resin of such a composition for forming the sleeve. |
