To provide a developing roller having a layer just below the surface, the layer suppressing a residual potential during repeated use without decreasing adhesion between layers and preventing image fog due to toner scattering, and having a surface layer preventing contamination due to fouling on the surface and having an appropriate elasticity and uniform charging for the toner to prevent image unevenness, and to provide an image forming method using the above developing roller.
The developing roller comprises an elastic layer made of silicone rubber around at least a conductive shaft and a plurality of resin layers formed on the elastic layer, and is characterized in that the resin forming the surface layer of the resin layers essentially comprises a silicone-copolymerized polyurethane and that forming the layer just below the surface layer essentially comprises a polyurethane resin-silica hybrid material.
COPYRIGHT: (C)2008,JPO&INPIT
KOBAYASHI NOBUAKI
OSHIBA TAKEO
OKUYAMA OKUSHI
SUGAMA KOICHI
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