RUBBER MEMBER AND DEVELOPING ROLLER MADE OF THE RUBBER MEMBER

摘要

PROBLEM TO BE SOLVED: To provide a rubber member showing low hardness and having abrasion resistance, and a developing roller made of the rubber member of preventing a decrease of print density without the decrease of durability.;SOLUTION: The developing roller is composed of a rubber member comprising two or more vulcanized rubber layers including at least a base layer and a surface layer. The hardness of the surface layer is larger than that of the base layer, and the hardness of the base layer is not more than 60 degrees according to JIS A hardness. The hardness of the laminate of all layers including the base layer and the surface layer is not more than 70 degrees according to JIS A hardness. The electric resistance of the laminate is not more than 10¹⁰Ω at 10°C under relative humidity of 20% at 100 V.;COPYRIGHT: (C)2008,JPO&INPIT