| 摘要 |
PURPOSE:To uniform electric characteristics, namely, reduce the variation width of specific resistance by manufacturing the sleeve for the conductive roll by molding while mixing two kinds of high polymer molding material compounds which differ in the content of conductive material particles. CONSTITUTION:Thermoplastic resin such as polyethylene resin, a rubber material such as natural rubber, thermosetting resin such as phenol resin, etc., are used alone or in combination as a high polymer material. Powder of carbon, graphite, metal or its oxide, etc., is used as the conductive material particles. Those are compounds A and B which differ in the content; and the specific resistance is preferably within a range of 10<3A<B<10<10>OMEGAcm and the mixture volume ratio is preferably within a range of (0.1-0.4)<=A/(A+B)<=(0.6-0.9). While two kinds of high polymer molding material compounds A and B are mixed, they are molded into a sleeve 9 by extrusion, etc., and metallic end cap 10 are incorporated to form a developing roll 3. |
