Process cartridge provided with cleaning unit

A process cartridge comprising:

• a photosensitive drum rotatable in a rotating direction;
• a developing roller defining an axial direction and having a peripheral surface, the peripheral surface having a first end portion at a first side and a second end portion at a second side opposite to the first side in the axial direction;
• a frame;
• a first side seal positioned between the frame and the first end portion of the developing roller and extending in the rotating direction;
• a second side seal positioned between the frame and the second end portion of the developing roller and extending in the rotating direction;
• a cleaning, roller positioned downstream of the developing roller in the rotating direction and including a roller portion in contact with the photosensitive drum, the cleaning roller being configured to allow developing agent on the photosensitive drum to pass through the cleaning roller and to collect paper dust on the photosensitive drum, the roller portion having a length in the axial direction longer than a distance in the axial direction between the first side seal and the second side seal;
• and
• a paper dust cleaner positioned downstream of the cleaning roller and upstream of the developing roller in the rotating direction, the paper dust cleaner being in contact with the photosensitive drum, the paper dust cleaner being configured to allow the developing agent on the photosensitive drum to pass through the paper dust cleaner and to collect the paper dust on the photosensitive drum, the paper dust cleaner having a length in the axial direction smaller than the distance in the axial direction between the first side seal and the second side seal.

A process cartridge comprising:

• a photosensitive drum having a peripheral surface configured to face a transfer roller, the photosensitive drum being rotatable in a rotating direction;
• a developing roller configured to supply developing agent to the peripheral surface, the developing roller defining an axial direction and having a first end at a first side and a second end at a second side opposite to the first side in the axial direction;
• a frame accommodating the developing roller;
• a first seal member positioned between the frame and the first end of the developing roller, and the first seal member having a first end at the first side inwardly in the axial direction;
• a second seal member positioned between the frame and the second end of the developing roller, and the second seal member having a second end at the second side inwardly in the axial direction;
• a cleaning roller positioned downstream of the transfer roller in the rotating direction and including a roller portion which is in contact with the peripheral surface of the photosensitive drum, the cleaning roller being configured to allow the developing agent on the peripheral surface of the photosensitive drum to pass through the cleaning roller and to collect paper dust on the peripheral surface of the photosensitive drum, the roller portion having a length in the axial direction longer than a distance in the axial direction between the first end of the first seal member and the second end of the second seal member;
• and
• a cleaning brush positioned downstream of the cleaning roller and upstream of the developing roller in the rotating direction, the cleaning brush being in contact with the photosensitive drum, the cleaning brush being configured to allow the developing agent on the peripheral surface of the photosensitive drum to pass through the cleaning brush and to collect paper dust on the peripheral surface of the photosensitive drum, the cleaning brush having a length in the axial direction smaller than the distance in the axial direction between the first end of the first seal member and the second end of the second seal member.