ROLLER FOR DEVELOPING MACHINE AND ITS PRODUCTION

摘要

PURPOSE:To attain satisfactory electrification characteristics, low coefft. of friction, and low strain of a roller for developing machine with one-layer structure without forming additive outer layers on the surface of the roller and to provide the roller at high productivity and low cost. CONSTITUTION:A rubber cylindrical part 1 of a roller A for a developing machine consists of polyurethane elastomer produced by dispersing conductive carbon in a graft modified polyol and hardening with polyisocyanate. The graft modified polyol is obtd. by allowing a prepolymer to react with hydroxyl groups of polyols having the average number of functional groups between >=2.0 and <3.0. The proportion of the prepolymer is 5-20mol% to the hydroxyl group of the polyol. This prepolymer is obtd. by the reaction of isocyanate with active hydrogen of polysiloxane having active hydrogen at one end of the molecule.