a cleaning unit usable with an image forming apparatus includes a cleaning blade , supported by a frame and including a free end contactable to an image bearing drum , for removing a developer from the drum ; a first seal provided between the frame and the blade by injection molding into the frame adjacent to a longitudinal end portion of the blade , the first seal being effective to prevent developer leakage ; and a second seal provided between the drum and the frame in contact with the free end of the blade adjacent to the longitudinal end portion , wherein the first seal includes a seal portion contacting the blade , and a seat supporting the second seal , the seat being deformable to move the second seal to urge the second seal to the free end of the blade when the drum is mounted to the frame .