Abstract: An image forming apparatus includes a control unit configured to change, to a light quantity different from a plurality of reference light quantities, a light quantity per unit area of a surface of an electrical charge retention layer of a photosensitive member when an exposure unit exposes the surface in correspondence with a plurality of gradation levels, based on a plurality of exposure potentials corresponding to the plurality of gradation levels which is acquired by exposing with the exposure unit the surface with each of the plurality of reference light quantities corresponding to the plurality of gradation levels, and measuring with the measurement unit the plurality of exposure potentials of the photosensitive member which is formed by the exposure with the plurality of reference light quantities.

Abstract: At least one partial measurement region is set in the longitudinal direction in a printable region of a photosensitive drum 3. After the photosensitive drum 3 has been charged to a constant potential with a charging roller 6, different potentials are set in the partial measurement region and a region excluding partial measurement region with a laser scanner 4, partial discharge information of the partial measurement region is detected by discharge information detection unit, and a bias voltage in image formation that is applied to the charging roller 6 is corrected on the basis of the value of the partial discharge information.

Abstract: A regulation member includes an opposed surface and a contact surface in a portion corresponding to an image forming area. The opposed surface is opposed to a developer bearing member. The contact surface protrudes from the opposed surface and has a height different from that of the opposed surface. An end seal seals a gap between a frame body, the developer bearing member, and the regulation member. The regulation member further includes an area not having the contact surface between the image forming area and a sealing area in which the regulation member and the end seal overlap. In the sealing area, a step between the opposed surface and the contact surface has a height of greater than or equal to 0 mm and not greater than 0.10 mm.

Abstract: A developing blade has a protrusion that protrudes toward a developing roller in an opposing portion facing the developing roller. When a height of the protrusion from an opposing surface that faces the developing roller at a position further toward a tip side than the protrusion is denoted by H (mm) and a length of the opposing surface extending toward the tip side perpendicular to an axial line direction of the developing roller is denoted by L (mm), when viewing a cross section perpendicular to a rotation axis of the developing roller, the following conditions are satisfied: 0.05?H?0.3, and 0.15?L?1.0.

Abstract: A developing blade has a protrusion that protrudes toward a developing roller in an opposing portion facing the developing roller. When the potential difference between a supply bias and a developing bias is denoted by ?(V), a contact pressure of the developing blade with respect to the developing roller is denoted by X (gf/cm), and a height of the protrusion from the opposing surface that faces the developing roller at a position further toward a tip side than the protrusion is denoted by H (mm) and a length of the opposing surface in the rotation direction of the developing roller is denoted by L (mm), when viewing a cross section perpendicular to the rotation axis of the developing roller, 0.05?H?0.1, 0.15?L?1.0, and 15?X?60 are established, and at least ???5*X?125 is satisfied.

Abstract: The present disclosure relates a developer container for accommodating a developer. The developer container includes a conductive path. The conductive path includes a resin.

Abstract: An image forming apparatus includes: an acquisition portion that acquires, based on a current value detected by a detection unit, a discharge start voltage value between a photosensitive body and a charging member, in a voltage value of a voltage applied to the charging member, the discharge start voltage value being acquired from at least one of a plurality of measurement regions set by dividing an image forming region of the photosensitive body, in which an electrostatic image is formed, into a plurality of regions in a longitudinal direction orthogonal to a recording material conveyance direction; and a control portion that performs unevenness suppression control to reduce unevenness, in the longitudinal direction, of density of a developer image transferred onto the recording material based on the discharge start voltage value.

Abstract: An image forming apparatus includes: a transfer member that secondarily transfers a developer image primarily transferred to a intermediate transfer medium, to a recording medium; a charging member that charges residual developer remaining on the intermediate transfer medium after the developer image is secondarily transferred from the intermediate transfer medium to the recording medium; and a storage portion that stores information on a image bearing member. A bias applied to the charging member is changed based on the information when the residual developer charged by the charging member is collected by being transferred from the intermediate transfer medium to the image bearing member.

Abstract: An image forming apparatus including: image forming stations each including: a photosensitive drum; a charger configured to charge the drum; a transfer device configured to transfer a developer image on the drum onto an intermediate transfer member; and a cleaner configured to remove developer from the drum; an exposure device configured to expose the drum to form a latent image; the intermediate transfer member; a memory storing information on the drum; and a controller configured to control at least one of the charger, transfer device, and exposure device in the station based on the information in the memory to provide a predetermined potential difference between the drum and the transfer device to form an electric field therebetween in a reverse direction to that in an image formation in order to move the developer from the intermediate transfer member to the drum to collect the developer by the cleaner.

Abstract: An image forming apparatus includes photosensitive drums, charging devices, an exposure unit configured to expose surfaces of photosensitive drums to generate a non-image portion potential and expose the surfaces to generate an image portion potential, developing members configured to make a developer adhere to an area where the image portion potential is generated to form a developer image on the photosensitive drums, a control unit configured to control an intensity of the charging voltage, and an acquisition unit configured to acquire thicknesses of photosensitive layers of the respective plurality of photosensitive drums, wherein the control unit is configured to set the intensity of a charging voltage applied to the common charging devices according to a maximum thickness among the thicknesses acquired by the acquisition unit, and individually control the output of the first laser power for the photosensitive drum according to surface potentials of the charged photosensitive drums.

Abstract: The image forming apparatus is capable of executing a color mode for forming images of a plurality of colors using the plurality of developer bearing members, and a mono-mode for forming images of mono color using one developer bearing member of the plurality of developer bearing members. The control unit, when the color mode is executed, determines the charging bias and, the first laser power and the second laser power for respective image bearing members, based on information about the plurality of image bearing members. The control unit, when the mono-mode is executed, determines the charging bias and, the first laser power and the second laser power to image bearing member for mono-mode, based on information about image bearing member for mono-mode.

Abstract: An image forming apparatus can switch between a color mode, in which an image is formed by sequentially transferring color toner images formed by developing members in an overlapping manner, and a mono mode, in which an image is formed by using one developing member. The developing member used in the mono mode develops the toner image to be transferred secondly or thereafter in the color mode, an exposure device exposes a non-image portion where the toner image is not formed on the surface of an image carrier at an exposure amount smaller than an exposure amount for an image portion where the toner image is formed, and, in the mono mode, the exposure amount at which the exposure device exposes the non-image portion of the image carrier in the case the image is formed in the mono mode is smaller than the color mode.

Abstract: An image forming apparatus includes a rotatable photosensitive member, an exposure unit for exposing a surface of the photosensitive member to light, and a detecting portion for detecting a lifetime of the photosensitive member on the basis of a thickness of a charge transporting layer of the photosensitive member and an amount of the light received by the charge transporting layer of the photosensitive member.

Abstract: A developer container includes a stirring member that stirs a developer and a conductive resin sheet that comes into contact with the stirring member when the stirring member rotates. The developer container detects developer quantity using capacitance.

Abstract: The present disclosure relates a developer container for accommodating a developer. The developer container includes a conductive path. The conductive path includes a resin.

Abstract: An image forming apparatus includes image forming portions provided along a movement direction of a recording material conveying member or an intermediary transfer member and including a first portion and a second portion provided downstream of the first portion with respect to the movement direction; a detecting portion for detecting information on a developer deterioration state at the first portion; a storing portion for storing a relationship between a detection result of the detecting portion and an amount of the developer to be back-transferred at the second portion; and an outputting device for outputting a signal relating to an amount of the developer accommodated in the accommodating portion at the second portion on the basis of the detection result of the detecting portion, the relationship stored in the storing portion, and information on the developer used for image formation at each of the first and second portions.

Abstract: An image forming apparatus includes a rotatable drum; a developing device for developing a latent image formed on the drum into a developer image; and a cleaning blade for removing developer remaining on the drum after the developer image is transferred from the drum onto a developer image receiving member. After image formation, a predetermined amount of strain of the cleaning blade is released and the drum is subsequently rotated. The drum is subsequently rotated in a direction identical to a rotation direction of the drum during image formation.

Abstract: An image forming apparatus includes photosensitive drums, charging devices, an exposure unit configured to expose surfaces of photosensitive drums to generate a non-image portion potential and expose the surfaces to generate an image portion potential, developing members configured to make a developer adhere to an area where the image portion potential is generated to form a developer image on the photosensitive drums, a control unit configured to control an intensity of the charging voltage, and an acquisition unit configured to acquire thicknesses of photosensitive layers of the respective plurality of photosensitive drums, wherein the control unit is configured to set the intensity of a charging voltage applied to the common charging devices according to a maximum thickness among the thicknesses acquired by the acquisition unit, and individually control the output of the first laser power for the photosensitive drum according to surface potentials of the charged photosensitive drums.

Abstract: An image forming apparatus includes: a rotatable photosensitive member; an exposure unit for exposing a surface of the photosensitive member to light; and a detecting portion for detecting a lifetime of the photosensitive member on the basis of first information on a thickness of a charge transporting layer of the photosensitive member and second information on an amount of the light received by the charge transporting layer of the photosensitive member.

Abstract: An image forming apparatus including: image forming stations each including: a photosensitive drum; a charger configured to charge the drum; a transfer device configured to transfer a developer image on the drum onto an intermediate transfer member; and a cleaner configured to remove developer from the drum; an exposure device configured to expose the drum to form a latent image; the intermediate transfer member; a memory storing information on the drum; and a controller configured to control at least one of the charger, transfer device, and exposure device in the station based on the information in the memory to provide a predetermined potential difference between the drum and the transfer device to form an electric field therebetween in a reverse direction to that in an image formation in order to move the developer from the intermediate transfer member to the drum to collect the developer by the cleaner.