Patent ID: 8041250

Claim:
A developing device comprising: a housing having an opening; a developing roller comprising a roller main body having a circumferential surface configured to carry developer thereon, the developing roller being rotatably supported to the housing, and at least a part of the circumferential surface of the roller main body being exposed through the opening of the housing; and seal members respectively disposed to face both end portions of the circumferential surface of the roller main body with respect to a rotational axis direction thereof and to press contact with the roller main body to prevent leakage of the developer from the opening, wherein each of the seal members comprises: a base material formed of an elastic element; and a sliding frictional member that is formed of fibers and contacts with the circumferential surface of the roller main body such that the roller main body frictionally slides on the sliding frictional member, wherein both edges of the circumferential surface of the roller main body with respect to the rotational axis direction thereof are brought into contact with the base materials, wherein an outer side edge of the sliding frictional member with respect to the rotational axis direction is disposed further inwards than an edge of the roller main body, and an outer side edge of the base material with respect to the rotational axis direction is disposed further outwards than the edge of the roller main body, and wherein the sliding frictional member is configured to contact the circumferential surface of the roller main body over the overall width of the sliding frictional member in the rotational axis direction.