CPC G03G 15/0818 (2013.01) [G03G 15/0808 (2013.01)] | 7 Claims |
1. A developing roller having two end portions and a central portion disposed between the two end portions in an extension direction of an axial, comprising an elastic layer, a coat layer formed on the elastic layer, and end portion coat layers only formed on outermost surfaces on the two end portions, wherein
the end portion coat layer comprises a conductive material,
a ratio (Ω1/Ω2) of a resistance value Ω1 at an axial central part of the end portion coat layer to a resistance value Ω2 at an axial central part of the coat layer is 1.6 or less, and
an absolute value (|Ω1−Ω2|) of a difference between the resistance value Ω1 at the axial central part of the end portion coat layer and the resistance value Ω2 at the axial central part of the coat layer is 0.7 GΩ or less.
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