| 摘要 |
PURPOSE:To smoothen a surface and to realize a development roll which is suitable for direct contact type electronic picture development method by forming a resin magnet dielectric layer on a shaft center surface, by magnetizing the layer to multipole, by removing a desired amount of the surface by machining or grinding and by enlarging a half value width of magnetic field intensity by magnetic pole. CONSTITUTION:A thin ferrite resin magnetic dielectric layer 2 is formed in a periphery of a columnar shaft core 1 formed of an iron material. The resin magnetic dielectric layer 2 is formed by performing coating extruding formation, insertion formation, etc., of a resin magnet composition which is formed by mixing ferrite magnetic powder and thermoplastic resin for a surface of the shaft core 1. As for manufacture of a multipolar magnetic dielectric roll A, the resin magnetic dielectric layer 2 is first provided as a layer to a surface of the shaft core 1. The dielectric layer 2 is magnetized to multipole by a magnetic yoke B having a number of comb-like tooth cores 3, A desired amount of its surface layer part is removed by machining or grinding. A surface is smoothened through such a thinning process. |
