A process cartridge includes an electrophotographic photosensitive member, a developing roller, a cleaning blade, a developer container including an opening, a developer conveyance member, a driving force transmission member having a driving force transmitted from the developer conveyance member, a seal member configured to seal the opening, and a winding member configured to wind the seal member such that the opening is opened, and the driving force transmission member is configured to take a first position at which the driving force is not transmitted to the winding member and a second position at which the driving force is transmitted to the winding member, and wherein the driving force transmission member is further configured to move from the first position to the second position after rotation of the developer conveyance member.