A waste toner collecting device includes an intermediate collection box, a conveying path, a conveying screw, an exhaust path and a floating toner collection chamber. The conveying path is provided in the intermediate collection box. The conveying screw is rotatable in the conveying path. Through the exhaust path, air containing a floating toner is sucked and passed. The floating toner collection chamber is provided on a part of the exhaust path in the intermediate collection box. The floating toner collection chamber has a discharge opening opened to an inside of the intermediate collection box and a discharge door. Rotation of the conveying screw in a normal direction turns the discharge door into a storage position where the discharge opening is closed. Rotation of the conveying screw in a reverse direction turns the discharge door into a discharge position where the discharge opening is opened.

A binding process device includes an advancing member and a binding process unit. The advancing member advances toward a corner of a recording-medium bundle having multiple edges and having the corner at an intersection position where the edges intersect. The binding process unit performs a binding process on the recording-medium bundle by causing the advancing member to advance toward the corner and is capable of performing the binding process at a first position and at a second position located closer to the intersection position than the first position.

An image forming apparatus includes a developing unit that contains an electrostatic charge image developer which contains a carrier and an electrostatic charge image developing toner, wherein the toner includes toner particles which contain a polyester resin, which is a polycondensate of a polycarboxylic acid and a polyol, and has a glass transition temperature of 50° C. to 70° C., the polyol includes a polyol not having a bisphenol A structure in a range of 50% by weight to 100% by weight, and a melt viscosity A of the toner at 110° C. after storage for 2 hours under the environment of absolute humidity of 82.7 (g/m.sup.3) and a melt viscosity B of the toner at 110° C. after storage for 2 hours under the environment of absolute humidity of 16.5 (g/m.sup.3) each are in the ranges specified in the specification.

A developing device includes a developer container that accommodates an electrostatic image developer including toner containing a toner particle and a zinc stearate particle, a ratio (D.sub.T/D.sub.S) of a volume-average particle size (D.sub.T) of the toner particle to a volume-average particle size (D.sub.S) of the zinc stearate particle being about 1.9 or more; a developer carrier that supplies the toner to an image carrier; a supply conveyor that supplies the electrostatic image developer while conveying the electrostatic image developer; a mixing conveyor that conveys the electrostatic image developer while mixing the electrostatic image developer; and a partition disposed between the supply conveyor and the mixing conveyor. The electrostatic image developer is moved from the supply conveyor to the mixing conveyor through a first passage and is moved from the mixing conveyor to the supply conveyor through a second passage.

An image forming apparatus includes an electrophotographic photoreceptor having a photosensitive layer that includes at least one of a hindered phenol antioxidant and a benzophenone ultraviolet absorber, a charging device, an electrostatic latent image forming device, a developing device, and a transfer device that includes an intermediate transfer belt whose electric field dependence of a volume resistivity is 0.003 or less (log Ω.Math.cm)/V in a voltage range of from 500 V to 1,000 V, and transfers a toner image formed on a surface of the electrophotographic photoreceptor onto a recording medium through the intermediate transfer belt and erases charges from the surface of the electrophotographic photoreceptor by applying current to the electrophotographic photoreceptor after the toner image formed on the surface of the electrophotographic photoreceptor has been transferred onto the intermediate transfer belt.

An image forming apparatus is capable of performing a second image forming operation in which a peripheral velocity ratio of a developer bearing member to an image bearing member becomes greater than that in a first image forming operation, and in which a potential difference between a developing bias applied to the developer bearing member and a supply bias applied to a supply member becomes a potential difference at which a urging force causing a developer at the contact portion between the developer bearing member and the supply member to move from the supply member to the developer bearing member becomes smaller than that in the first image forming operation, or becomes a potential difference at which a urging force causing the developer to move from the developer bearing member to the supply member is generated.

Provided is a powder container having a new structure capable of stable discharge and transport of a powder contained in a container by enabling the powder to be reliably discharged to the outside of the package while preventing the powder from spilling and flying out of the container. The powder container has a container body (138) for transporting powder contained therein from a first end side (138a) to a second end side (138b) thereof by self-rotating; a nozzle receiver (139) having a nozzle receiving hole (insertion section) (139a) arranged inside the second end side of the container body and configured to allow a transport nozzle (162) having a powder receiving inlet (170) to be inserted therein, and a supply port 139b arranged in at least a part of the nozzle receiver (139) and configured to supply the powder in the container body (138) to the powder receiving inlet (170): and a shutter (140) supported by the nozzle receiver 139 and configured to open and close the nozzle receiving hole (insertion section) 139a by sliding in response to insertion of the transport nozzle 162 into the nozzle receiver (139).

An image forming apparatus for forming an image on a recording material by a plurality of color materials, the apparatus includes: a determination unit configured to determine, based on converted data that are converted from image data corresponding to each image formed by the plurality of color materials, values each relating to an area of a respective color material caused to adhere to a recording material; and a detection unit configured to detect, based on the values each relating to the area of the respective color material that the determination unit determines, an overlapping of color materials.

A powder collection device includes a transport pipe, a powder collection container supported turnably on a pivot center provided in an attachment part of an apparatus body and removably attached to a position to cover an attachment part of the apparatus body, a pipe-side opening/closing mechanism that opens a discharging port by moving an opening/closing lid in cooperation with an operating member of the powder collection container when the powder collection container is turned to the position to cover the attachment part, and a container-side opening/closing mechanism that opens a collection port by moving a container opening/closing lid in cooperation with an operating member of the transport pipe when the powder collection container is turned to the position to cover the attachment part. The discharging port is disposed on a side of a vertical line including the pivot center different from the apparatus body.

A cleaning device scrapes off and removes toner that has adhered to a surface of a rotating photoreceptor, and includes: a cleaning member formed of an elastic body; a leaf spring member for pressing the cleaning member against the surface of the photoreceptor; and a support portion supporting the leaf spring member. The cleaning member is fixed to one end of the leaf spring member, and the other end of the leaf spring member is fixed to the support portion with a cushioning member formed of an elastic body interposed therebetween. The cushioning member is fixed to the other end of the leaf spring member by an adhesive.