Patent ID: 10338493

Abstract:
A developing roller (1) is provided, which includes a tubular porous inner layer (2) of a foamed product of a semiconductive rubber composition containing an ethylene propylene rubber and a paraffin oil, and an outer layer (4) of a seamless tube of a semiconductive thermoplastic polyamide elastomer provided on an outer peripheral surface (3) of the inner layer (2), and has an overall Asker-C hardness of not less than 30 degrees and not greater than 60 degrees. A production method is also provided, which includes the steps of: preparing a tube having a thickness T of 100 to 400 μm and having an inner diameter D2 for an outer layer; preparing a tubular inner layer having an outer diameter D1; and press-inserting the inner layer into the tube; wherein an interference represented by a difference D1- D2 between the outer diameter D1 of the inner layer and the inner diameter D2 of the tube is 100 to 400 μm.