A calculating portion 300 acquires resistance of a carrier liquid in a carrier tank. A resistance calculating portion 302 acquires the resistance of the carrier liquid on the basis of a liquid amount of a carrier liquid for each of numbers of times of passing of the carrier liquid through a separation and extraction device and resistance of the carrier liquid for each of the numbers of times of passing of the carrier liquid through the separation and extraction device. The liquid amount of a carrier liquid for each of numbers of time of passing is calculated by a deterioration degree distribution calculating portion 301 and is stored in a memory 201. As regards the resistance of the carrier liquid for each of the numbers of times of passing, the resistance of the carrier liquid after passing through the separation and extraction device is stored in the memory 201 in advance for each of the numbers of times of passing. A carrier supply discriminating portion 202 discriminates whether or not a carrier liquid for supply should be supplied, on the basis of the acquired resistance of the carrier liquid. A controller 200 controls a pump 51 for supply on the basis of this discrimination.

An image forming apparatus of the present invention includes: a determination unit that determines toner application amounts based on image data; a memory device that stores a set of instructions; and at least one processor that executes the set of instructions to: control fixing temperature for fixing a toner image formed from the image data to a printing medium in accordance with information created for each printing page by analyzing the determined toner application amounts; and fix the toner image to a printing medium at the controlled fixing temperature. The determination unit divides each printing page of the image data into a plurality of meshes of a predetermined size and determines positions corresponding to the meshes obtained by the dividing, and counts the toner application amounts of pixels in each of the meshes based on a determination result of the determining of the positions and the image data.

An image forming apparatus includes an image bearing member to form a toner image on a recording material with a liquid developer containing a toner and a carrier liquid, wherein the carrier liquid contains a first substance, charged to an opposite polarity to a charge polarity of the toner, for imparting an electrical polarity to the toner, and a second substance, higher in volume resistivity than the first substance, a cleaning portion to collect the liquid developer remaining on the image bearing member after the toner image is transferred onto the recording material, a toner separating device to separate the collected liquid developer into the toner and the carrier liquid, and a carrier separating device to separate the carrier liquid into the carrier liquid containing the first substance and the carrier liquid containing the second substance by applying an electric field to the carrier liquid.

A downtime relating to formation and detection of a detection image is reduced. An image forming apparatus includes a controller configured to calculate a first conversion unit to convert a gradation of input image data so that density output for the input image data becomes a first density output characteristic based on a first detection result of the detection image detected by a density sensor in a first mode. The controller generates a second conversion unit to convert the gradation of the input image data so that the density output for the input image data becomes a second density output characteristic in the second mode based on the detection result in the first mode and correction information, and further updates the correction information based on a second detection result of the detection image detected by the density sensor in the second mode and the first detection result.

A toner cartridge includes a housing, a toner conveying shaft and a percussion device. The housing has a barrel portion, in which toners are contained, and a transmission portion rotatably disposed at an end of the barrel portion. The toner conveying shaft is rotatably disposed inside the barrel portion of the housing and drivenable by the transmission portion of the housing to rotate. The percussion device is configured to intermittently vibrate the barrel portion of the housing when the toner conveying shaft rotates. As such, when the percussion device intermittently vibrates the barrel portion of the housing, the toners attached on an inner wall surface of the barrel portion will be shaken down for being further discharged out of barrel portion, thereby reducing the residual amount of the toners that are contained in the barrel portion of the housing.

A toner cartridge includes a housing, a toner conveying shaft and a percussion device. The housing has a barrel portion, in which toners are contained, and a transmission portion rotatably disposed at an end of the barrel portion. The toner conveying shaft is rotatably disposed inside the barrel portion of the housing and drivenable by the transmission portion of the housing to rotate. The percussion device is configured to intermittently vibrate the barrel portion of the housing when the toner conveying shaft rotates. As such, when the percussion device intermittently vibrates the barrel portion of the housing, the toners attached on an inner wall surface of the barrel portion will be shaken down for being further discharged out of barrel portion, thereby reducing the residual amount of the toners that are contained in the barrel portion of the housing.

A photo drum may be to receive a color separation. A controller may be to change a location of the color separation on the photo drum from a first location to a second location when a separation location history for the color separation is outside of a threshold range.

An image-forming apparatus includes an electrophotographic photosensitive member including a conductive base and a single-layer photosensitive layer disposed on the conductive base, the single-layer photosensitive layer including a binder resin, a charge-generating material, a hole-transporting material, and an electron-transporting material; and a developing unit including a developing roller that develops an electrostatic latent image formed on a surface of the electrophotographic photosensitive member with a developer including a toner in order to form a toner image, the developing roller being arranged to come into contact with the photosensitive layer. The ratio R/P of the content R [mass %] of the binder resin in the photosensitive layer to the pressing force P [N/mm] at which the developing roller is pressed against the photosensitive layer is about 11.5 or more and about 19.6 or less.

Identification information of a toner bottle recorded in an IC chip is included in a toner bottle. When information on remaining amount of toner is successful, a printing apparatus notifies a management server with identification information of the toner bottle and information on remaining amount of toner, obtains toner usage amount used in printing processing according to an execution of printing processing based on print job, and updates information on remaining amount recorded in the IC chip according to usage amount. When reading of information of the IC chip fails, updating of information on remaining amount recorded in the IC chip, according to usage amount of toner used in printing processing according to execution of printing processing based on print job, which is received when the reading fails, is suppressed. Notification including information indicating the reading has failed as the information on remaining amount is transmitted.

A developing device includes a hardware processor that performs control in which a developer circulation state is switched between a first state and a second state depending on states of the developer in the first and the second regions. The first state is a state in which a developer circulation path is formed in each of the first and the second regions, and the second state is a state in which a single developer circulation path is formed all through the first and the second regions.