Image forming apparatus

An image forming apparatus comprising:

• a photosensitive drum that is rotatable;
• a charging unit configured to form a charging portion between the photosensitive drum and the charging unit and charge a surface of the photosensitive drum in the charging portion;
• a developing unit configured to contact with the photosensitive drum to form a developing portion and supply, in the developing portion, toner to the surface of the photosensitive drum charged by the charging unit;
• a transfer unit configured to contact with the photosensitive drum to form a transfer portion and transfer, in the transfer portion, the toner supplied to the photosensitive drum to a transfer target;
• a brush configured to contact with the surface of the photosensitive drum downstream of the transfer portion and upstream of the charging portion in a rotational direction of the photosensitive drum;
• an applying unit configured to apply a voltage to the brush;
• a drive unit configured to rotate the photosensitive drum;
• and
• a control unit configured to control the applying unit and the drive unit, wherein
• the control unit is configured to execute a first activation control and a second activation control,
• the first activation control starts the rotation of the photosensitive drum in a state in which a potential difference between the voltage applied to the brush and a potential of the surface of the photosensitive drum is a first potential difference,
• the second activation control starts the rotation of the photosensitive drum in a state in which the potential difference between the voltage applied to the brush and the potential of the surface of the photosensitive drum is a second potential difference,
• each of the first potential difference and the second potential difference is formed such that an electrostatic force from the brush toward the surface of the photosensitive drum acts on a particle charged to a polarity opposite to a normal polarity of the toner, and
• the second potential difference has an absolute value greater than an absolute value of the first potential difference.