Developing roller and method of producing the same

1. A method of producing a developing roller, comprising:

providing a roller core having an electrically conductive layer provided on a circumferential surface thereof,

applying a reaction mixture containing a fluorine-containing polyol, an isocyanate compound, and a reactive silicone oil having an active hydrogen to a surface of said conductive layer, and

subjecting said reaction mixture to a reaction condition for reacting said flourine-containing polyol and said reactive silicone oil with said isocyanate compound.

2. The method according to claim 1 , wherein said fluorine-containing polyol is a copolymer polyol containing ethylene tetrafluoride monomer units as the main component.

3. The method according to claim 1 , wherein said conductive layer is formed of an electrically conductive rubber material comprising at least one rubber selected from silicone rubber, an acrylonitrile-butadiene rubber, a silicone-modified ethylene-propylene rubber, and a urethane rubber, each imparted with electrical conductivity.

4. The method according to claim 1 , wherein said reactive silicone oil is represented by the following formula (1) or (2):

where, in the formulas (1) and (2), each R represents —C 3 H 6 OC 2 H 4 OH or —C 3 H 6 OCH 2 —C(CH 2 OH) 2 C 2 H 5 , and n is an integer of about 20 or less.

5. The method according to claim 1 , further comprising the step of controlling the frictional charge series of the covering layer by changing the mixing ratio of the fluorine-containing polyol to the reactive silicone oil.

6. The method of claim 1 , wherein the reaction mixture is heated to react said fluorine-containing polyol with said isocyanate compound.

7. The method of claim 1 , wherein the reaction mixture is applied to said surface of the conductive layer at a thickness to form a covering layer having a thickness of from 4 μm to 30 μm.

8. The method of claim 1 , further comprising the step of adding a filler to the reaction mixture.