Silicone rubber roller for electrophotography and method of producing the same.

摘要

The first form of the present invention provides an electrically conductive rubber roller for electrophotography which produces little change in electric resistance with changes in environment, concerning charging and image transferring processes in copying machines and laser beam printers. It is characterized by comprising a porous body of crosslinked silicone composition, wherein at least a silica type filler, carbon black and a foaming agent are contained in siloxane polymer and in that the electric resistance is 10<3> - 108. The second form of the invention provides a silicone rubber roller for electrophotography in which trace amounts of low polymerization degree siloxanes and non-functional silicone oils have been substantially completely removed, so that there is no danger of contaminating the photoreceptor not only immediately after the use of the roller but also for a long time thereafter, and a method of producing the same. A molding material containing a silicone rubber type compound in which the sum of the concentrations of low polymerization degree siloxanes and non-functional silicone oils is not more than 5000 ppm, is crosslinked and molded in roller form, and after molding it is vacuum-heated.