Abstract: A decurling device includes a belt, a roller, and a heat source. The heat source heats either or both of the belt and the roller. The belt has a first holding surface extending in a rotational direction of the belt. The roller has a second holding surface extending in a rotational direction of the roller. The decurling device has either or both of a plurality of belt through holes penetrating the first holding surface and a plurality of through holes penetrating the second holding surface.

Abstract: An inkjet recording apparatus (1) includes an image forming section (40), a decurler (20), a changing section (50), a first calculating section (72), storage (60), a second calculating section (73), and a controller (75). The image forming section (40) ejects ink onto a sheet (S). The decurler (20) bends the sheet (S). The changing section (50) changes a bending amount of the sheet (S). The first calculating section (72) calculates an ink ejection rate (?) to the sheet (S) for each of areas of the sheet (S). The storage (60) stores therein first bending information (62) indicating a first target bending amount (?) of a specific area of the sheet (S) corresponding to the ink ejection rate (?) to the specific area. The second calculating section (73) calculates a second target bending amount of each of the areas. The controller (75) controls the changing section (50) based on the second target bending amounts.

Abstract: A decurling device includes a first conveyance path, a second conveyance path, a first switch, a decurler, and a controller. A sheet is conveyed along the first conveyance path or the second conveyance path. The first switch switches a route of conveyance of the sheet to the first conveyance path or the second conveyance path. The sheet has a first main surface and a second main surface. The decurler is located in the second conveyance path. The decurler corrects curl of the sheet. In a situation in which a weight per unit area of the sheet is smaller than a first threshold value, the controller controls the first switch such that the sheet is conveyed along the second conveyance path.

Abstract: A de-curling device de-curls a sheet and includes an endless belt, a de-curling roller, a nip width adjusting mechanism, and a belt tension adjusting mechanism. The endless belt is looped around a pair of supporting rollers. The de-curling roller is provided between the pair of supporting rollers and has a first outer circumferential surface pressed against a second outer circumferential surface of the endless belt to form a nip portion at which the endless belt curves along the first outer circumferential surface, the de-curling roller being configured to de-curl the sheet passing through the nip portion. The nip width adjusting mechanism adjusts the nip width by moving the de-curling roller in a direction intersecting the second outer circumferential surface of the endless belt. The belt tension adjusting mechanism adjusts the tension of the endless belt according to the nip width adjusted by the nip width adjusting mechanism.

Abstract: A decurling device includes a belt, a roller, and a heat source. The heat source heats either or both of the belt and the roller. The belt has a first holding surface extending in a rotational direction of the belt. The roller has a second holding surface extending in a rotational direction of the roller. The decurling device has either or both of a plurality of belt through holes penetrating the first holding surface and a plurality of through holes penetrating the second holding surface.

Abstract: An inkjet recording apparatus includes an image forming section, a heater, a calculation section, storage, and a determination section. The image forming section ejects ink onto a sheet in which first to M-th regions are defined (M is an integer of at least 2). The heater includes first to M-th heat sources and heats an n-th region of the sheet using an n-th heat source (n is an integer of at least 1 and no greater than M). The calculation section calculates an ink ejection rate of ink to be ejected onto the n-th region. The storage stores therein heating information indicating whether it is necessary to heat the n-th region. The determination section determines whether or not to cause the n-th heat source to generate heat.

Abstract: A decurling device includes a first conveyance path, a second conveyance path, a first switch, a decurler, and a controller. A sheet is conveyed along the first conveyance path or the second conveyance path. The first switch switches a route of conveyance of the sheet to the first conveyance path or the second conveyance path. The sheet has a first main surface and a second main surface. The decurler is located in the second conveyance path. The decurler corrects curl of the sheet. In a situation in which a weight per unit area of the sheet is smaller than a first threshold value, the controller controls the first switch such that the sheet is conveyed along the second conveyance path.

Abstract: A decurling device includes a decurler. The decurler includes a first dryer roller, a second dryer roller, and a heat source. The heat source is disposed at the first dryer roller to heat the first dryer roller. The first dryer roller and the second dryer roller rotate while holding a sheet therebetween to convey the sheet.

Abstract: A liquid developer includes an insulating carrier liquid, colored particles, an organic macromolecular compound, and a dispersant. The organic macromolecular compound is dissolved in the carrier liquid. The organic macromolecular compound is formed of a copolymer resin selected from cyclic olefin copolymers and styrene-based elastomers. The colored particles are dispersed in the carrier liquid. Each of the colored particles includes a binder resin and carbon black. A mass ratio (V/OP) of a content (V) of the dispersant in the liquid developer to a content (OP) of the organic macromolecular compound in the liquid developer is 0.2 or larger and 0.8 or smaller.

Abstract: A developing unit has a voltage-applicator (80) to apply a developing bias voltage to a developing roller (72). The voltage-applicator (80) applies the developing bias voltage for a first duration to apply an AC voltage having a rectangular waveform, and a second duration to stop applying the AC voltage. The AC voltage has a duty ratio of 50% or more in a direction for causing toner to develop an electrostatic latent image. The number of cycles of the AC voltage in the first duration is two or more, and the AC voltage has a voltage in a direction for pulling the toner back to the developing roller, just before transition to the second duration. The developing unit suppresses occurrence of image unevenness due to a fluctuation in developing gap. Thus, an image forming apparatus equipped with the developing unit forms a high-quality image while suppressing image unevenness.

Abstract: A developing device uses a two-component developer including at least carriers and toners. The toners are supplied to an image bearing member bearing an electrostatic latent image so that a toner image is developed from the electrostatic latent image. The developing device has a developing roller arranged to oppose the image bearing member; and a magnetic roller arranged to oppose the developing roller. The magnetic roller retains the two-component developer to supply toners to the developing roller. The developing roller and the magnetic roller are rotationally driven in directions to be opposite from one another at an opposed position, and a magnetic pole of the magnetic roller and a magnetic pole of the developing roller have magnetic polarities different from one another at the opposed position. A surface roughness of the magnetic roller is greater than a surface roughness of the developing roller.

Abstract: An image forming apparatus has a photoconductive member, and a developing roller develops a latent image on the photoconductive member by a first alternating-current bias in the form of a rectangular wave. The following relationships are satisfied in calculating the duty ratio (D1) of the first alternating-current bias using an application period of voltage in a direction to transfer the toner from the developing roller towards the photoconductive member as a positive period: a CV value in the number particle size distribution of the toner is ?25%, 4 ?m?Dt?7 ?m, 105 ?·cm?pv?109 ?·cm, 0.4 ?m?Ra?1.5 ?m, and 35%?D1?75%. where Dt denotes the volume average particle diameter of the toner, pv denotes the intrinsic resistance value of a developing roller surface, Ra denotes the arithmetic average roughness of the developing roller surface.

Abstract: An image forming apparatus has a photoconductive member on which a latent image is to be formed, a developing roller for developing the latent image on the photoconductive member by a first bias. A magnetic roller forms a magnetic brush thereon with a two-component developer and forms a thin toner layer on the developing roller by a second bias. The developing roller is aluminum with a surface treated for high resistance. The thickness (T) of the toner layer and the duty ratio (D1) of the first alternating-current bias satisfy relationships of the following equations for calculating the duty ratio (D1) using an application period of a voltage in a direction to transfer the toner from the developing roller towards the photoconductive member as a positive period: 7 ?m?T?13 ?m, and 35%?D1?70%.

Abstract: A grid wire cleaning mechanism is provided to prevent a reduction in image quality due to the surface of the electrostatic latent image carrier not being uniformly charged as a result of corona products adhering unevenly to the surface of the grid wires to extend the life of the grid wires and grid wire contact member. A first abrading member 71 abrades grid wires 224. A movement device 73 moves the first abrading member 71 in the same direction as the direction of extension of the grid wires 224. A humidity measurement unit 741 measures the humidity near the grid wires 224. The operation control unit 743 operates the movement device 73 when cleaning the grid wires 224, but does not operate the movement device 73 when the humidity measured by the humidity measurement unit 741 exceeds a predetermined threshold value.

Abstract: To provide an image forming device that is capable of preventing deterioration of the image quality through preventing deterioration of the toner even if frequency of making a copy is low. The image forming device includes: a developing part having a developing roller for achieving development by electrostatically attaching a toner onto an electrostatic latent image formed on a photoreceptor; a transferring part for transferring a developed toner image to a paper; and a cleaner part for removing and collecting the toner remained on the photoreceptor after transferring, wherein the developing roller is rotary-driven at a lower speed than a speed of development under a standby state. The image forming device includes a standby-state refresh control part for forcibly consuming an amount of the toner that is calculated based on accumulated time of the low-speed rotary drive.

Abstract: A developing device uses a two-component developer including at least carriers and toners. The toners are supplied to an image bearing member bearing an electrostatic latent image so that a toner image is developed from the electrostatic latent image. The developing device has a developing roller arranged to oppose the image bearing member; and a magnetic roller arranged to oppose the developing roller. The magnetic roller retains the two-component developer to supply toners to the developing roller. The developing roller and the magnetic roller are rotationally driven in directions to be opposite from one another at an opposed position, and a magnetic pole of the magnetic roller and a magnetic pole of the developing roller have magnetic polarities different from one another at the opposed position. A surface roughness of the magnetic roller is greater than a surface roughness of the developing roller.

Abstract: An image forming apparatus has a photoconductive member on which a latent image is to be formed, a developing roller for developing the latent image on the photoconductive member by a first bias. A magnetic roller forms a magnetic brush thereon with a two-component developer and forms a thin toner layer on the developing roller by a second bias. The developing roller is aluminum with a surface treated for high resistance. The thickness (T) of the toner layer and the duty ratio (D1) of the first alternating-current bias satisfy relationships of the following equations for calculating the duty ratio (D1) using an application period of a voltage in a direction to transfer the toner from the developing roller towards the photoconductive member as a positive period: 7 ?m?T?13 ?m, and 35%?D1?70%.

Abstract: An image forming apparatus has a photoconductive member, and a developing roller develops a latent image on the photoconductive member by a first alternating-current bias in the form of a rectangular wave. The following relationships are satisfied in calculating the duty ratio (D1) of the first alternating-current bias using an application period of voltage in a direction to transfer the toner from the developing roller towards the photoconductive member as a positive period: a CV value in the number particle size distribution of the toner is ?25%, 4 ?m?Dt?7 ?m, 105 ?·cm?pv?109 Q?cm, 0.4 ?m?Ra?1.5 ?m, and 35%?D1?75%. where Dt denotes the volume average particle diameter of the toner, pv denotes the intrinsic resistance value of a developing roller surface, Ra denotes the arithmetic average roughness of the developing roller surface.

Abstract: A developing unit has a voltage-applicator (80) to apply a developing bias voltage to a developing roller (72). The voltage-applicator (80) applies the developing bias voltage for a first duration to apply an AC voltage having a rectangular waveform, and a second duration to stop applying the AC voltage. The AC voltage has a duty ratio of 50% or more in a direction for causing toner to develop an electrostatic latent image. The number of cycles of the AC voltage in the first duration is two or more, and the AC voltage has a voltage in a direction for pulling the toner back to the developing roller, just before transition to the second duration. The developing unit suppresses occurrence of image unevenness due to a fluctuation in developing gap. Thus, an image forming apparatus equipped with the developing unit forms a high-quality image while suppressing image unevenness.

Abstract: To provide an image forming device that is capable of preventing deterioration of the image quality through preventing deterioration of the toner even if frequency of making a copy is low. The image forming device includes: a developing part 44 having a developing roller 443 for achieving development by electrostatically attaching a toner onto an electrostatic latent image formed on a photoreceptor 41; a transferring part 46 for transferring a developed toner image to a paper; and a cleaner part 47 for removing and collecting the toner remained on the photoreceptor 41 after transferring, wherein the developing roller 443 is rotary-driven at a lower speed than a speed of development under a standby state. The image forming device includes a standby-state refresh control part 240 for forcibly consuming an amount of the toner that is calculated based on accumulated time of the low-speed rotary drive.