Image forming apparatus for an intermediate transfer of a toner image and for reversely transferring collected developer to an image bearing member

An image forming apparatus capable of performing an image forming operation for forming an image on a recording material, the image forming apparatus comprising:

• an image bearing member configured to be rotatable;
• an exposure unit configured to expose a surface of the image bearing member so as to form an electrostatic latent image on the image bearing member surface;
• a developer bearing member configured to supply developer to the electrostatic latent image so as to form a developer image on the image bearing member surface, wherein the developer bearing member, bearing the developer, contains additive particles;
• an intermediate transfer member configured to form a transfer portion in contact with the image bearing member;
• a transfer member configured to transfer the developer image developed on the image bearing member surface onto the intermediate transfer member at the transfer portion;
• a holding unit configured to collect, after the developer image transferred on the intermediate transfer member has been transferred onto the recording material, residual developer remaining on the intermediate transfer member and temporarily hold the residual developer, wherein the holding unit includes a charging member and, by applying a voltage having a polarity opposite to a charging polarity of the developer used for developing an electrostatic latent image, the charging member charges the developer borne by the intermediate transfer member;
• a cleaning member configured to remove developer borne by the image bearing member, wherein the cleaning member forms a contact portion when in contact with the image bearing member;
• and
• a controller configured to control to perform a cleaning operation for moving a collected developer held by the holding unit to the intermediate transfer member and then for reversely transferring the collected developer from the intermediate transfer member to the image bearing member,
• wherein, in a case where a voltage of the developer charging polarity and the voltage having the polarity opposite to the developer charging polarity are alternately applied to move the collected developer held by the holding unit to the intermediate transfer member, the charging member gradually increases a voltage difference between the voltage of the developer charging polarity and the voltage having the polarity opposite to the developer charging polarity that are alternately applied.

An image forming apparatus capable of performing an image forming operation for forming an image on a recording material, the image forming apparatus comprising:

• an image bearing member configured to be rotatable;
• an exposure unit configured to expose a surface of the image bearing member so as to form an electrostatic latent image on the image bearing member surface;
• a developer bearing member configured to supply developer to the electrostatic latent image so as to form a developer image on the image bearing member surface, wherein the developer bearing member, bearing the developer, contains additive particles;
• an intermediate transfer member configured to form a transfer portion in contact with the image bearing member;
• a transfer member configured to transfer the developer image developed on the image bearing member surface onto the intermediate transfer member at the transfer portion;
• a holding unit configured to collect, after the developer image transferred on the intermediate transfer member has been transferred onto the recording material, residual developer remaining on the intermediate transfer member and temporarily hold the residual developer;
• a cleaning member configured to remove developer borne by the image bearing member, wherein the cleaning member forms a contact portion when in contact with the image bearing member;
• and
• a controller configured to control to perform the image forming operation and a cleaning operation for moving a collected developer held by the holding unit to the intermediate transfer member and then for reversely transferring the collected developer from the intermediate transfer member to the image bearing member,
• wherein, when a non-image forming operation which performs an operation other than the image forming operation is performed, the controller controls to reversely transfer the collected developer, which has been moved to the intermediate transfer member by the cleaning operation, from the intermediate transfer member to a first region on the image bearing member at the transfer portion, and controls to supply the developer from the developer bearing member to the contact portion on the image bearing member surface by exposing a fifth region on the image bearing member surface and supplying the developer from the developer bearing member to the exposed fifth region, and
• wherein the controller controls such that the fifth region on the image bearing member surface passes through the contact portion after the first region on the image bearing member surface passes through the contact portion.