Patent ID: 8550968
Filing Date: 2013-10-08
Classification: G03G

Abstract:
1. A developing roller comprising a shaft, an elastic layer formed on an outer periphery of the shaft and a surface coating layer formed on an outer peripheral face of the elastic layer, in which the surface coating layer comprises a urethane resin formed by crosslinking a lactone-modified polyol with a polyisocyanate, wherein the urethane resin of the surface coating layer has a structure that a silicone having a siloxane bond is introduced into a resin skeleton, wherein the urethane resin has a structure that a silicone having a siloxane bond and a hydroxyl group or an amino group in its both terminals is introduced into a urethane portion, and wherein the lactone-modified polyol has a number average molecular weight (Mn) converted to polystyrene of 1000-5000 as measured through a gel permeation chromatography and a molecular weight distribution (Mw/Mn) represented by a ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) converted to polystyrene of not more than 2.5 as measured through the gel permeation chromatography.