Abstract: In an image forming apparatus, a control unit performs a control to cause an exposing unit to expose a plurality of image bearing members at different times to form exposure regions on the plurality of image bearing members, to acquire results acquired by applying direct current voltage lower than discharge start voltage to a plurality of abutting members by an applying unit when the exposure regions pass by abutting parts against the abutting members and detected by a detecting unit, and to, based on the acquired results of the detections, acquire information regarding the surface potentials of the plurality of image bearing members.

Abstract: Provided is an electrophotographic rotatable pressing member having further durability. The electrophotographic rotatable pressing member includes: a substrate; and an elastic layer formed on the substrate, the elastic layer containing a silicone rubber and a needle-shaped filler dispersed in the silicone rubber and having hollow parts, wherein, when cutting the elastic layer along a cross section including a center axis of the substrate in a longitudinal direction of the electrophotographic rotatable pressing member, and a total of each sectional area of the hollow parts in a unit area A2 of a cross-sectional surface is defined as A1, a standard deviation of an area ratio A1/A2 is 0.08 or less.

Abstract: A roller for use with an image fixing device for fixing an image on a recording material includes a core metal, and an elastic layer provided around the core metal. In the elastic layer, a filler bundle including a plurality of fiber-like fillers is dispersed.

Abstract: An image forming apparatus includes image forming units each of which includes an image bearing member, a contact charging member, and a developer bearing member of a toner, applies a charging bias in a direction in which the toner moves from the image bearing member to the charging member in an image forming period, and applied a charging bias of an opposite polarity relative to that in the image formation in a cleaning period, and collects the toner by the developer bearing member. In consecutive image formation, a charging bias in the image forming period is applied in a first interval period and which is between first and second image forming periods and a second interval period which is between second and third image forming periods. An absolute value of a charging bias applied in the second interval period is larger than that applied in the first interval period.

Abstract: A developer carrying member is disposed below a storage chamber of a frame and has a surface configured such that a plurality of dielectric portions are dispersed on a conductive portion, an upper region of the storage chamber of the frame is enlarged further in a horizontal direction than a lower region in which the developer carrying member is disposed, and the frame has a lower guide surface and includes a curved surface having a tangent plane inclined at a first angle equal to or greater than a degree of an angle of repose of the developer and less than 90 degrees, in an inner wall of the lower region, and an upper guide surface includes a curved surface having a tangent plane inclined at a second angle that is less than the first angle relative to a horizontal plane in an inner wall of the upper region.

Abstract: Provided is an electrophotographic rotatable pressing member having further durability. The electrophotographic rotatable pressing member includes: a substrate; and an elastic layer formed on the substrate, the elastic layer containing a silicone rubber and a needle-shaped filler dispersed in the silicone rubber and having hollow parts, wherein, when cutting the elastic layer along a cross section including a center axis of the substrate in a longitudinal direction of the electrophotographic rotatable pressing member, and a total of each sectional area of the hollow parts in a unit area A2 of a cross-sectional surface is defined as A1, a standard deviation of an area ratio A1/A2 is 0.08 or less.

Abstract: When a new development device is mounted, a control unit of an image forming apparatus identifies a development device type. When an identification result corresponds to a first development device containing a first amount of developer, an agitation member operates in a first mode. When the identification result corresponds to a second development device containing a second amount of developer higher than the first amount, the agitation member operates in a second mode. A second operation amount of the agitation member in the second mode is higher than a first operation amount of the agitation member in the first mode. A developer containing chamber of the development device is provided with a discharge opening from which the developer is discharged. The operations in the first and second modes are performed after a sealing member sealing the discharge opening is removed and also before a normal image forming process is executed.

Abstract: In an image forming apparatus which includes a plurality of image forming units each including an image bearing member, a contact charging member, and a developer bearing member for forming toner of normal polarity, and which, in a printing operation, applies a charging bias having a first direction, in a cleaning operation, applies a charging bias having a second direction, and recovers residual toner remaining on the image bearing member without used for printing by the developer bearing member, before performing the cleaning operation, when successively performing the printing operation on a plurality of recording materials including a first recording material and a second recording material, which is used for printing following the first recording material, the charging voltage larger in absolute value in the printing operation for the second recording material than in the printing operation for the first recording material is applied.

Abstract: An image forming apparatus using a contact charging method includes a control unit capable of executing cleaning in a post-rotation step at the end of a job and in an inter-image step during execution of the job. The cleaning involves moving toner adhering to a charging member from the charging member to an image bearing member. The job is a series of operations started by a predetermined start instruction and involving forming an image on one or more recording materials and outputting the one or more recording materials. When an instruction to start the next job is input during execution of cleaning in the post-rotation step, the control unit stops the cleaning in the middle of the execution, starts the next job, and adjusts timing for executing subsequent cleaning on the basis of information relating to the amount of cleaning executed before being stopped in the middle of the execution.

Abstract: Provided is an electrophotographic rotatable pressing member having further durability. The electrophotographic rotatable pressing member includes: a substrate; and an elastic layer formed on the substrate, the elastic layer containing a silicone rubber and a needle-shaped filler dispersed in the silicone rubber and having hollow parts, wherein, when cutting the elastic layer along a cross section including a center axis of the substrate in a longitudinal direction of the electrophotographic rotatable pressing member, and a total of each sectional area of the hollow parts in a unit area A2 of a cross-sectional surface is defined as A1, a standard deviation of an area ratio A1/A2 is 0.08 or less.

Abstract: An image forming apparatus using a contact charging method includes a control unit capable of executing cleaning in a post-rotation step at the end of a job and in an inter-image step during execution of the job. The cleaning involves moving toner adhering to a charging member from the charging member to an image bearing member. The job is a series of operations started by a predetermined start instruction and involving forming an image on one or more recording materials and outputting the one or more recording materials. When an instruction to start the next job is input during execution of cleaning in the post-rotation step, the control unit stops the cleaning in the middle of the execution, starts the next job, and adjusts timing for executing subsequent cleaning on the basis of information. relating to the amount of cleaning executed before being stopped in the middle of the execution.

Abstract: A roller usable in an image fixing device for an electrophotographic image forming apparatus includes a first elastic layer; a second elastic layer provided closer to a center of the roller than the first elastic layer, the second elastic layer having a thermal conductivity in a thickness direction higher than that of the first elastic layer; a third elastic layer provided between the first elastic layer and the second elastic layer, wherein an indentation elastic modulus EIT1 of the first elastic layer, an indentation elastic modulus EIT2 of the second elastic layer, and an indentation elastic modulus of the third elastic layer satisfy E1T1<E1T3<E1T2.

Abstract: A control unit of an image forming apparatus controls, in an image forming mode, a potential difference obtained by subtracting the voltage applied to the developer bearing member from the voltage applied to the regulating member so that the potential difference is set to the polarity of the developer, and the control unit controls, in a lubricant discharge mode, the potential difference obtained by subtracting the voltage applied to the developer bearing member from the voltage applied to the regulating member so that the potential difference is set to the polarity of the lubricant or “0”.

Abstract: An image forming apparatus operable in a mode of forming an image using only a part of image forming stations. In the mode, a developing device contacts an image bearing member in a part of the image forming stations, and the developing device is spaced from the image bearing member in the rest of the image forming stations. The contact pressure between the image bearing member and a transferring device is made smaller in the rest than in the part. The image forming operation in the mode is executed while the image bearing members of the part and the rest are rotated. A controller is configured such that when the operation in the mode is continuously executed for a time period longer than a predetermined period, the contact pressure in the rest is made larger than the above-mentioned smaller contact pressure.

Abstract: In an image forming apparatus, a control unit performs a control to cause an exposing unit to expose a plurality of image bearing members at different times to form exposure regions on a plurality of image bearing members, to acquire results acquired by applying direct current voltage lower than discharge start voltage to a plurality of abutting members by an applying unit when the exposure region pass by the abutting parts against the abutting members and detected by a detecting unit, and to, based on the acquired results of the detections, acquire information regarding the surface potentials of the a plurality of image bearing members.

Abstract: Provided is a pressure roller for an image heating device that forms a nip part together with a heating member, the pressure roller including at least a mandrel, a first elastic layer, and a second elastic layer provided between the mandrel and the first elastic layer, wherein the first elastic layer has open-cell voids, is made of rubber, and has a thickness of at least 50 ?m and less than 500 ?m, and the second elastic layer is made of solid rubber.

Abstract: An image forming apparatus using a contact charging method includes a control unit capable of executing cleaning in a post-rotation step at the end of a job and in an inter-image step during execution of the job. The cleaning involves moving toner adhering to a charging member from the charging member to an image bearing member. The job is a series of operations started by a predetermined start instruction and involving forming an image on one or more recording materials and outputting the one or more recording materials. When an instruction to start the next job is input during execution of cleaning in the post-rotation step, the control unit stops the cleaning in the middle of the execution, starts the next job, and adjusts timing for executing subsequent cleaning on the basis of information. relating to the amount of cleaning executed before being stopped in the middle of the execution.

Abstract: A roller usable in an image fixing device for an electrophotographic image forming apparatus includes a first elastic layer; a second elastic layer provided closer to a center of the roller than the first elastic layer, the second elastic layer having a thermal conductivity in a thickness direction higher than that of the first elastic layer; a third elastic layer provided between the first elastic layer and the second elastic layer, wherein an indentation elastic modulus EIT1 of the first elastic layer, an indentation elastic modulus EIT2 of the second elastic layer, and an indentation elastic modulus of the third elastic layer satisfy EIT1<EIT3<IIT2.

Abstract: A control unit of an image forming apparatus controls, in an image forming mode, a potential difference obtained by subtracting the voltage applied to the developer bearing member from the voltage applied to the regulating member so that the potential difference is set to the polarity of the developer, and the control unit controls, in a lubricant discharge mode, the potential difference obtained by subtracting the voltage applied to the developer bearing member from the voltage applied to the regulating member so that the potential difference is set to the polarity of the lubricant or “0”.

Abstract: Provided is an electrophotographic rotatable pressing member having further durability. The electrophotographic rotatable pressing member includes: a substrate; and an elastic layer formed on the substrate, the elastic layer containing a silicone rubber and a needle-shaped filler dispersed in the silicone rubber and having hollow parts, wherein, when cutting the elastic layer along a cross section including a center axis of the substrate in a longitudinal direction of the electrophotographic rotatable pressing member, and a total of each sectional area of the hollow parts in a unit area A2 of a cross-sectional surface is defined as A1, a standard deviation of an area ratio A1/A2 is 0.08 or less.