Cartridge

1. A cartridge detachably mountable to a main assembly of an image forming apparatus, the cartridge comprising:

a frame;

a rotatable member for carrying developer, the rotatable member being supported by the frame;

a blade member contacting the rotatable member;

a first seal member provided between the blade member and the frame, the first seal member extending in a rotational axis direction of the rotatable member, the first seal member being configured to seal a gap between the blade member and the frame, and the first seal member including an extending portion at a longitudinal end portion thereof, the extending portion extending in a crossing direction that crosses the rotational axis direction of the rotatable member; and

a second seal member provided between the rotatable member and the frame, the second seal member extending in the crossing direction, the second seal member contacting the rotatable member and the frame, the second seal member being configured to seal a gap between the rotatable member and the frame, and the second seal member including a first surface contacting the extending portion of the first seal member,

wherein the frame includes a second surface opposite of the first surface of the second seal member across the extending portion of the first seal member in the rotational axis direction of the rotatable member, the second surface sandwiching the extending portion of the first seal member with the first surface of the second seal member in the rotational axis direction of the rotatable member.

2. A cartridge according to claim 1 , further comprising an urging portion for urging the second seal member toward the extending portion of the first seal member.

3. A cartridge according to claim 1 , wherein a direction in which the first surface of the second seal member extends and a direction in which the second surface of the frame extends cross each other.

4. A cartridge according to claim 1 , wherein the first seal member is an elastic member.

5. A cartridge according to claim 1 , wherein the rotatable member is a developing roller for supplying the developer to an image bearing member, and the blade member is a developing blade for regulating a thickness of a layer of the developer on the rotatable member.

6. A cartridge according to claim 5 , further comprising a photosensitive member as the image bearing member.

7. A cartridge according to claim 1 , wherein the rotatable member is a photosensitive drum, and the blade member is a cleaning blade for removing foreign matter from a surface of the rotatable member.

8. A cartridge according to claim 1 , wherein the direction in which the first surface extends is a direction inclined with respect to the rotational axis direction of the rotatable member.

9. A cartridge according to claim 1 , wherein the direction in which the second surface extends is a direction inclined with respect to the rotational axis direction of the rotatable member.

10. A cartridge according to claim 1 , wherein the frame includes a bearing surface for supporting the first seal member and a wall that projects toward the blade member relative to the bearing surface and on which the second surface is formed, and

wherein the wall and the blade member do not contact each other.

11. A cartridge according to claim 1 , wherein a direction in which the extending portion of the first seal member extends is a direction along a direction in which the second seal member extends.