Abstract: An image forming apparatus includes: an image carrier; a solid lubricant; a lubricant application member that scrapes off the solid lubricant and applies the scraped solid lubricant to a surface of the image carrier; a colorimeter that performs colorimetry of a colorimetric surface of the solid lubricant; and a hardware processor that sets a lubricant application condition such that a predetermined amount of lubricant is applied on the basis of a colorimetric result obtained by the colorimeter.

Abstract: An image forming apparatus includes an image carrier; an exposure device which draws an electrostatic latent image on the image carrier; a developer which uses a developing roller facing the image carrier to supply a developing agent to the electrostatic latent image formed on the image carrier and to develop a toner image; a developing current detector which detects a developing current flowing between the image carrier and the developing roller during developing by the developer; and a controller which controls the above. The controller performs forced toner discharge control in which a predetermined toner image is developed on the image carrier by the developer and the toner is forcibly discharged from the developer. The controller controls a toner discharge amount in the forced toner discharge control based on a current value detected by the developing current detector.

Abstract: An image forming apparatus includes: an image carrier; a charging roller that charges the image carrier; a power supply part that applies a charging voltage to the charging roller; a current measurement part that measures a value of a DC component of a current flowing between the image carrier and the charging roller at at least two timings having mutually different elapsed times; and a hardware processor that measures an elapsed time from a start of application of the charging voltage by the power supply part, calculates a coefficient of an approximate expression indicating a relationship between the value of the DC component of the current flowing between the image carrier and the charging roller, and the elapsed time, and performs judgment related to life of the charging roller on the basis of the coefficient and a predetermined threshold.

Abstract: An image forming apparatus includes: an image carrier; a charging roller that charges the image carrier; a power supply part that applies a charging voltage to the charging roller; a current measurement part that measures a value of a DC component of a current flowing between the image carrier and the charging roller at at least two timings having mutually different elapsed times; and a hardware processor that measures an elapsed time from a start of application of the charging voltage by the power supply part, calculates a coefficient of an approximate expression indicating a relationship between the value of the DC component of the current flowing between the image carrier and the charging roller, and the elapsed time, and performs judgment related to life of the charging roller on the basis of the coefficient and a predetermined threshold.

Abstract: A charging device is configured to apply electric charge to an image carrier provided outside the charging device. The charging device includes: a cored bar member; and a conductive resin layer provided on a surface of the cored bar member. The conductive resin layer has a film thickness of 200 ?m or less. Filtered maximum waviness in an axial direction of the cored bar member is 8 ?m or less in a range of a reference length of 60 mm.

Abstract: A charging device is configured to apply electric charge to an image carrier provided outside the charging device. The charging device includes: a cored bar member; and a conductive resin layer provided on a surface of the cored bar member. The conductive resin layer has a film thickness of 200 ?m or less. Filtered maximum waviness in an axial direction of the cored bar member is 8 ?m or less in a range of a reference length of 60 ?m.

Abstract: An image forming apparatus includes a photoreceptor, a charging unit, an exposing unit, a developing unit, a transfer unit, a lubricant supply unit, a cleaning unit and a lubricant removal unit. The lubricant supply unit supplies a lubricant to a surface of the photoreceptor and is disposed at a point which is an upstream side of the cleaning unit and a downstream side of the developing unit in a rotation direction of the photoreceptor. The lubricant removal unit removes the lubricant from the surface of the photoreceptor and is disposed at a point which is the downstream side of the cleaning unit and the upstream side of the developing unit in the rotation direction of the photoreceptor.

Abstract: Disclosed is an electrophotographic photoreceptor including a conductive support, a photosensitive layer on the conductive support and a surface layer on the photosensitive layer. The surface layer includes a cured resin prepared by polymerization of a compound having two or more radically polymerizable functional groups per molecule, the cured resin containing an organic resin fine particle and a metal oxide fine particle, and the organic resin fine particle comprising a resin containing a structural unit derived from at least one of melamine and benzoguanamine, the organic resin fine particle having a number average primary particle size of 0.01 to 3.00 ?m.

Abstract: An image forming apparatus includes a photoreceptor, a charging unit, an exposing unit, a developing unit, a transfer unit, a lubricant supply unit, a cleaning unit and a lubricant removal unit. The lubricant supply unit supplies a lubricant to a surface of the photoreceptor and is disposed at a point which is an upstream side of the cleaning unit and a downstream side of the developing unit in a rotation direction of the photoreceptor. The lubricant removal unit removes the lubricant from the surface of the photoreceptor and is disposed at a point which is the downstream side of the cleaning unit and the upstream side of the developing unit in the rotation direction of the photoreceptor.

Abstract: To provide an image forming apparatus that suppresses occurrence of image deletion in a high-temperature and high-humidity environment and provides good toner cleanability.

Abstract: In an image forming apparatus, the charging bias supply circuit generates a second charging bias voltage that causes no positive discharge between the charging unit and the photoreceptor drum, during a recovery mode, the charging unit charges the surface of the photoreceptor drum upon application of the second charging bias voltage during the recovery mode, and the cleaning unit rubs the surface of the photoreceptor drum charged by the second charging bias voltage, during the recovery mode.

Abstract: An image forming apparatus includes an electrophotographic photoreceptor, a proximity-type charging unit to negatively charge the surface of the photoreceptor, an exposing unit to form an electrostatic latent image on the surface of the photoreceptor, a developing unit to develop the electrostatic latent image with a toner to form a toner image, a transferring unit to transfer the toner image onto a transfer medium, a fixing unit to fix the transferred toner image on the transfer medium, and a cleaning unit to remove residual toner on the photoreceptor. The photoreceptor comprises a conductive support, a photosensitive layer formed over the conductive support, and a protective layer formed over the photosensitive layer. The protective layer of the photoreceptor contains a binder resin, a particulate P-type semiconductor, and a particulate cross-linked resin composed of an insulating cross-linked polymer.

Abstract: To provide an image forming apparatus that suppresses occurrence of image deletion in a high-temperature and high-humidity environment and provides good toner cleanability.

Abstract: Disclosed is an electrophotographic photoreceptor including a conductive support, a photosensitive layer on the conductive support and a surface layer on the photosensitive layer. The surface layer includes a cured resin prepared by polymerization of a compound having two or more radically polymerizable functional groups per molecule, the cured resin containing an organic resin fine particle and a metal oxide fine particle, and the organic resin fine particle comprising a resin containing a structural unit derived from at least one of melamine and benzoguanamine, the organic resin fine particle having a number average primary particle size of 0.01 to 3.00 ?m.

Abstract: Fiber bundle forms loops protruding beyond a surface side of a base member with constant spaces therebetween, in at least one of opposite ends located in a direction perpendicular to a weaving direction (W) of a ribbon brush, a weft extending between neighboring loops passes under a warp, and a weft extending through the loop passes above the warp.

Abstract: A cleaning blade, which is configured to be pressed against a toner image carrier that rotates in one direction, for removing residual toner from the toner image carrier, the cleaning blade having: a contact layer that is located in a side to come into contact with the toner image carrier; and a supporting layer that is located in a side not to come into contact with the toner image carrier, wherein tensile stress characteristic curves of a material of the contact layer and a material of the supporting layer intersect with each other. An image forming apparatus having a toner image carrier and the cleaning blade.

Abstract: In an image forming apparatus, the charging bias supply circuit generates a second charging bias voltage that causes no positive discharge between the charging unit and the photoreceptor drum, during a recovery mode, the charging unit charges the surface of the photoreceptor drum upon application of the second charging bias voltage during the recovery mode, and the cleaning unit rubs the surface of the photoreceptor drum charged by the second charging bias voltage, during the recovery mode.

Abstract: A cleaning blade, which is configured to be pressed against a toner image carrier that rotates in one direction, for removing residual toner from the toner image carrier, the cleaning blade having: a contact layer that is located in a side to come into contact with the toner image carrier; and a supporting layer that is located in a side not to come into contact with the toner image carrier, wherein tensile stress characteristic curves of a material of the contact layer and a material of the supporting layer intersect with each other. An image forming apparatus having a toner image carrier and the cleaning blade.

Abstract: Fiber bundle forms loops protruding beyond a surface side of a base member with constant spaces therebetween, in at least one of opposite ends located in a direction perpendicular to a weaving direction (W) of a ribbon brush, a weft extending between neighboring loops passes under a warp, and a weft extending through the loop passes above the warp.

Abstract: An image forming apparatus having: an image carrier that moves in a direction while holding a toner image on its surface; a cleaner that is located downstream from a transfer point where a toner image is transferred from the image carrier, with respect to the moving direction of the image carrier, to remove residual toner and other residues from the surface of the image carrier; a lubricant supply device for supplying a lubricant to the surface of the image carrier; and a flattener for spreading out the lubricant supplied from the lubricant supply device over the surface of the image carrier by pressing its edge portion against the surface of the image carrier; wherein the flattener has an impact resilience within a range of 48% to 68% under temperature of 25° C., and the edge portion of the flattener is arranged counter the moving direction of the image carrier.