Abstract: An image forming apparatus which is free from occurrence of image noise due to the bleed phenomenon even without providing any contact-and-separation mechanism for the transfer member includes a control device which counts stop time elapsing from a stop to a restart of the image carrier, calculates an avoidance sheet count corresponding to the stop time at a restart of the image carrier, and makes a toner image carried on only part of the image carrier that has been out of the nip against the transfer member during the stop of the image carrier until the avoidance sheet count is reached after the restart of the image carrier.

Abstract: If an input of a continuous image forming job is received, a time for interrupting the continuous image forming job is decided based on an image area ratio of a toner image that is formed on a latent image carrier through the continuous image forming job and a predetermined number of formed images (the number of passed sheets) that is formed until a predetermined type of abnormal image is generated when continuous image formation is performed at the image area ratio. During an interruption period of the continuous image forming job, an idle rotation in which the latent image carrier rotates in a state in which the toner is not supplied to the latent image carrier by the developing unit is performed, and the cleaning process is performed.

Abstract: A development device includes a toner-containing chamber for containing supplied toner having an interior wall, a developer-containing chamber for containing developer including toner and carrier communicating with the toner-containing chamber; and a transport screw to transport the supplied toner from the toner-containing chamber to the developer-containing chamber, disposed in the toner-containing chamber so that there is no gap between the outer edge of the transport screw and the interior wall of the toner-containing chamber in a portion lower than a level of the supplied toner in the toner-containing chamber.

Abstract: A system of an apparatus collects, from a plurality of forming apparatuses, information about a status of occurrence of an error occurring on the plurality of forming apparatuses and a utilization environment of the plurality of forming apparatuses, executes control, if an error has frequently occurred and that the utilization environment has varied, for notifying information indicating that the error has frequently occurred on the plurality of forming apparatuses together with information about the varied utilization environment, and executes control, if the error has frequently occurred and the utilization environment has not varied, for notifying information indicating that the error has occurred on the plurality of forming apparatuses together with the information about the utilization environment.

Abstract: An image forming apparatus includes a high voltage generating circuit 91 that applies an oscillating voltage in which a DC voltage and an AC voltage are superimposed on each other, to a charging member 42 disposed in contact with an image carrier 41; a voltage control portion 96 that controls a peak-to-peak voltage of the AC voltage to a target voltage value; and an initial voltage adjusting portion 95 that sets a target voltage value based on a DC current value between the image carrier 41 and the charging member 42 which is detected by a current detecting portion 92. When an environmental condition which is used when the target voltage value is set changes, the initial voltage adjusting portion 95 performs an interrupt operation during an image forming process.

Abstract: An image forming apparatus of the present invention includes: an image carrier on whose surface is formed a latent image; a developing unit that forms a developer image with a developer including toner, carrier and additive; a transfer unit that transfers the developer image onto a recording medium; a recovery member that recovers the developer remaining on the surface of the image carrier after the developer image is transferred; a supply member that supplies, to the image carrier, a recovery promoter; and a voltage application unit that applies, to the supply member, an alternating-current voltage whose amplitude is changed in accordance with a change in the percentages of the amount of toner and the amount of carrier per unit area of a developer image forming portion of the developing unit.

Abstract: A first calculating unit calculates an allocation time required for forming a patch pattern. A second calculating unit calculates a maximum patch-pattern length of the patch pattern that can be formed within the allocation time based on the number of patch patterns that can be formed within the allocation time. A setting unit calculates a difference between an environmental temperature around the image forming apparatus and an environmental temperature at which the image forming condition stored in the storing unit is set, and newly sets an image forming condition for the patch patterns based on a result of comparing the difference with a predetermined threshold.

Abstract: In an MFP, when a count of printed sheets of paper exceeds a predetermined count, a controller reads, from internal counters, a frequency of a stabilization process executed in return, a frequency of a stabilization process executed automatically in printing, a frequency of a stabilization process executed manually based on a user's instruction, and a frequency of return, respectively. When the frequency of the stabilization process executed automatically is small while the frequency of the stabilization process executed manually is large, the controller raises a frequency level of execution of the stabilization process. When the frequency of the stabilization process executed manually is small, the controller lowers the frequency level of execution of the stabilization process.

Abstract: Provided is an image forming apparatus capable of performing stable charging and thus stable image formation over a long term by changing a charge control method based on various environments. An engine control section serves as a first applied voltage determining unit, obtains a relationship between an applied voltage and a discharge current amount to a charging roller, and determines a voltage value of an applied voltage corresponding to a predetermined discharge current amount. The engine control section serves as a second applied voltage determining unit and determines a voltage value of a voltage to be applied to the charging roller based on the environment information detected by the environmental sensor. The engine control section selects, as the voltage to be applied to the charging roller, any one of the voltage values determined by the first and the second applied voltage determining units based oh the environment information.

Abstract: A developing apparatus includes a developing container for accommodating a developer; a rotatable developer carrying member, provided in an opening of the developing container, for feeding the developer to a position opposing image bearing member to develop a latent image formed to the image bearing member; a first chamber, provided in the developing container, for supplying the developer to the carrying member; a second chamber, provided adjacent to the first chamber in the developing container, for accommodating the developer; a first feeding member, provided in the first chamber, for feeding the developer in the first chamber; a second feeding member, provided in the second chamber, for feeding the developer in a direction opposite to a feeding direction of the first feeding member; a partition member partitioning between the first chamber and the second chamber; an opening provided in each of opposite ends of the first chamber to form a circulation path between the first chamber and the second chamber; an

Abstract: Disclosed are printing methods, apparatus and systems to compensate for distortion caused by fusing toner to a media substrate. According to one exemplary embodiment, the method includes processing image data according to media characterization data for a measured fuser temperature. The media characterization data provides a basis to compensate for media substrate shrinkage due to fusing the printed image on the media substrate.

Abstract: An image forming apparatus includes: an image bearing body on which surface a solid lubricant is supplied, forming and bearing an image on the surface; a charging member to which a voltage is applied, being in contact with the image bearing body to impart a charge; a voltage applying section that applies the voltage to the charging member, capable of switching the voltage between superimposed voltage on which DC voltage and AC voltage are superimposed and non-superimposed voltage including only DC voltage; an image forming section that forms a toner image; a transfer device that transfers the formed toner image to a transferring body; a cleaning member that contacts the image bearing body to scrape unnecessary substance from the surface; and a voltage switching section that switches the voltage applied to the charging member between the superimposed voltage and the non-superimposed voltage according to an amount of the solid lubricant.

Abstract: The aim of the present invention is to provide an image forming apparatus that accurately detects surface temperature of a rotating body using a noncontact temperature detection section and corrects the detected temperature according to the temperature of the surrounding area. The present invention detects the temperature of a thermal unit and the temperature of a holding unit and corrects the temperature of the thermal unit based on the temperature of the holding unit so that effects from the temperature of a surrounding area can be corrected and the temperature can accurately be detected without scarring a surface of the rotating body. Accurate regulation of the surface temperature of the rotating body can therefore be performed.

Abstract: An image-forming device includes a media path extending through the image-forming device, and at least one image transfer nip positioned along the media path. An electrode is positioned subsequent to the nip with respect to the media path and is coupled to a voltage source. An electric field produced by the electrode and voltage source limits the degree of post-nip toner scattering by applying an electrostatic force to toner particles on media sheets passing along the media path. The image-forming device further includes a processor for monitoring a plurality of ambient conditions, for adjusting the voltage applied to the electrode, and optionally, for repositioning the electrode with respect to the media path.

Abstract: An image forming apparatus includes a reception unit, an image forming unit, a drive unit, a detection unit, a prediction unit, and a control unit. The image forming unit forms an image based on image information received by the reception unit. The drive unit controls an imaging forming unit drive. The detection unit detects temperature within the image forming apparatus. The prediction unit predicts a transition of temperature within the image forming apparatus and an image formation time based on the image information and the temperature within the image formation unit. The control unit is responsive to detected temperature and predicted image forming time. The control unit switches between image forming modes and controls the image forming apparatus to form an image in a short image forming time.

Abstract: According to one embodiment, an image forming apparatus includes a photoreceptor, a charging unit, an exposure unit, a developing unit, a transfer unit, a fixing unit, an environment detecting unit and a control unit. The charging unit includes a charger and a static eliminator. The charger contacts with a surface of the photoreceptor and charges the surface to a first voltage. The static eliminator contacts with the surface and discharges the surface to a second voltage. The environment detecting unit detects an environmental data. The control unit controls the first voltage based on the environmental data.

Abstract: Provided is an apparatus and method for supplying a charge voltage to an organic photoconductor (OPC) drum. The apparatus includes a storage unit for storing first service life information of the OPC drum according to a first supplying method, and second service life information of the OPC drum according to a second supplying method, a sensor unit for measuring information about conditions surrounding the apparatus, a control unit for selecting one of the first and second supplying methods according to the measured information and determining a charge voltage corresponding to the service life information according to the selected method, and a voltage supplying unit using the selected method to supply the determined charge voltage to the OPC drum.

Abstract: In a method or system for regulation of optical density in an electrographic printing method, a toner layer thickness of a toner image developed with a developer station is scanned with a sensor. The resulting toner layer thickness signal is used for regulation of inking in the developer station. A humidity is measured with a moisture sensor and the resulting humidity signal is used for at least one of compensation of moisture-dependent deviations of the toner layer thickness signal and regulation of the inking in the developer station.

Abstract: A xerographic marking engine adjusts a charging actuator value, such as an AC peak-to-peak voltage or an AC peak-to-peak current, based on a determined knee value, VKNEE, of a charge curve for an imaging apparatus photoreceptor within the xerographic marking engine and environmental sensor data. The environmental sensor data may measure environment temperature and environment humidity. In near A-zone environments, for example, operational environments in which the temperature is 80 degrees Fahrenheit and the relative humidity is 80%, the charging actuator value may be selected to achieve a predetermined photoreceptor wear rate that avoids print quality defects due to lateral charge migration. In other than A-zone environments, the charging actuator value may be selected to minimize the photoreceptor wear rate, while avoiding print quality defects. The described approach allows optimal photoconductor wear to be achieved, in all operational environments, without increasing the risk of print quality defects.

Abstract: An image forming apparatus is provided that has a developing agent holder arranged as opposed to an image holder having an electrostatic latent image formed thereon, the developing agent holder attaching the developing agent to the image holder, a developing agent supplying unit rotatably arranged in contact with the developing agent holder, the developing agent supplying unit supplying a developing agent to the developing agent holder, an adjustment unit capable of adjusting a contacting state between the developing agent holder and the developing agent supplying unit.

Abstract: A method and system for printing image documents using a variety of toners where some toners using a multi-development station having two or more development stations. These toners are co-printed prior to fixing, on the receiver by the multi-development station.

Abstract: An image forming apparatus is provided, which prevents occurrence of conveying malfunction or image failure due to variation of conveying speed caused by endurance of a fixing unit or a conveying unit, variation of using environment, or a type of a recording material. The image forming apparatus includes: a fixing unit for heating and fixing a toner image on a recording sheet (P); a secondary transferring portion for conveying the recording sheet (P) to the fixing unit; a loop sensor for detecting a degree of a loop of the recording sheet (P) generated according to a speed difference between a conveying speed of the fixing unit and a conveying speed of the secondary transferring portion; a CPU for controlling the conveying speed of the fixing unit; a fixing deliver sensor for detecting a used amount of the fixing unit; and an EEPROM for storing information on the used amount of the fixing unit detected by the fixing deliver sensor.

Abstract: An image forming apparatus includes a rotatable photosensitive drum, a charging apparatus to which a charging voltage is applied, an exposure apparatus forming an electrostatic image, a developing apparatus to which a development voltage is applied, a timer measuring an image formation time lapsed from start of rotation of the photosensitive drum and an image formation stop time lapsed from stop of the rotation of the photosensitive drum, and a temperature and humidity sensor detecting a temperature and a humidity of an atmosphere environment around the photosensitive drum. When the humidity is low, a charging voltage is controlled based on a measured result of the timer and detected results of the temperature and humidity sensor. When the humidity is high, the charging voltage is controlled based on the measured result of the timer and the temperature detected result of the temperature and humidity sensor without using humidity information.

Abstract: An image forming apparatus includes a development device including a development roller and a driving force receiving member, a movable member configured to move the development device between a development position and a retracting position, a first driving force transmission member configured to transmit a driving force to the movable member, a second driving force transmission member configured to engage with the driving force receiving member and transmit the driving force to the driving force receiving member, and a controller configured to perform drive control for the first driving force transmission member based on a temperature detected by a sensor.

Abstract: An image forming apparatus includes: a sheet feed unit that feeds a sheet to an image forming unit forming a toner image on the sheet; a fixing unit that fixes the toner image formed in the image forming unit to the sheet; and a control unit that controls the sheet feed unit, when starting duplex image formation for forming both sides of the sheet after an one-side image formation, the control unit retards a timing to cause the sheet feed unit to start the sheet feed operation as the number of sheet with an image formed on one side thereof in the one-side image formation is greater.

Abstract: Disclosed is an image forming apparatus which forms an image on a paper including a detection unit to detect a present temperature of one component or a plurality of components to be replaced among components constituting the image forming apparatus and a control unit to determine whether the component is replaceable or not based on the detected present temperature and to execute a replacement guide for the component which is determined to be replaceable.

Abstract: The first direct-current bias power supply applying the first direct-current bias Vdc1 and the first alternating-current bias power supply applying the first alternating-current bias Vac1 are connected to a development roller. The second direct-current bias power supply applying the second direct-current bias Vdc2 and the second alternating-current bias power supply applying the second alternating-current bias Vac2 are connected to a magnetic roller. The peak-to-peak value Vpp of the first alternating-current bias Vac1 applied to the development roller remains the same, and the second alternating-current bias Vac2 that is in phase with the first alternating-current bias Vac1 and that has a peak-to-peak value of a predetermined value or above is applied to the magnetic roller. Thus, the potential difference between the peak voltage of the development bias on the opposite polarity side to the polarity of the toner and the peak voltage of a supply bias is set at a predetermined value or below.

Abstract: A consumable component sorting system which make it possible to prolong the service life of a consumable component and reduce cost burdened on a user. An image forming apparatus collects information on its own operational environment or operational condition. A data server estimates a change in characteristics of the consumable component used in the image forming apparatus based on the information on the operational environment or the operational condition of the same collected thereby. A component managing server sorts out a consumable component suited to the operational environment or the operational condition of the image forming apparatus, based on the result of the estimation of the data server.

Abstract: An image forming apparatus includes a photosensitive member; charging device for electrically charging the photosensitive member; an exposure device for exposing to light the photosensitive member to form an electrostatic latent image; a developing device for developing the electrostatic latent image into a toner image; a transfer member for forming a transfer portion at which the toner image is to be transferred from the photosensitive member onto a transfer material; a voltage control portion for controlling a transfer voltage to be applied to the transfer member so that a current passing through the transfer member is constant; and a current setting device for setting a current value in constant current control by the voltage control portion so that the current value is decreased when a ratio of a potential difference between the transfer voltage and a light portion potential provided by the exposure device to a potential difference between the transfer voltage and a dark portion potential provided by the

Abstract: A disclosed developing device includes a toner carrying member having electrodes, a toner supply unit supplying the toner to the toner carrying member, and a hopping electric field generator unit generating electric field to cause the toner hopping on the toner carrying member by applying a pulse voltage to the electrodes. The hopping electric field generator unit includes a pulse voltage generator circuit generating the pulse voltage, a first direct-current power source supplying bias to the pulse voltage generator circuit for regulating a peak value of the pulse voltage, and a second direct-current power source having a same polarity with a toner charging polarity, and outputting a variable voltage level. The hopping electric field generator unit controls the peak value of the pulse voltage by changing an output of the first power source and a mean thereof by changing an output of the second power source.

Abstract: According to one embodiment, an image forming apparatus includes a developing unit configured to store a developer includes a toner and a carrier and to form a developer image, a toner attachment amount detection portion configured to detect an attachment amount of a toner formed on a photoconductor or an intermediate transfer body, a developing bias voltage change portion configured to change a plurality of developing bias voltages including a developing contrast voltage in a manner that the detected attachment amount of the toner becomes a value in a predetermined range, a carrier supply time correction portion configured to correct a carrier supply time in response to the value of the changed developing contrast voltage, and a carrier supply portion configured to supply a carrier in a corrected carrier supply time at a predetermined timing.

Abstract: An image forming apparatus and a method of monitoring power consumption of the image forming apparatus are provided. For each one of parts of the image forming apparatus selected for monitoring, part-specific power consumption information is obtained based on accumulated operation amount information. The obtained part-specific power consumption information is used to generate power consumption information indicating an amount of electric power consumed by at least a portion of the image forming apparatus.

Abstract: In an image forming method, an execution condition of forcible toner consumption is obtained based on an environmental value at a time of final image formation and a present environmental value, the forcible toner consumption is executed under the execution condition, and image formation is performed after calibration.

Abstract: An image forming apparatus including a first developing device including a first developer carrying member for carrying a developer containing toner, wherein a developing voltage including an AC component is applicable to the first developer carrying member to develop an electrostatic image; a second developing device including a second developer carrying member for carrying a developer containing toner, wherein a developing voltage including an AC component is applicable to the second developer carrying member to develop an electrostatic image; a transferring device for transferring a toner image formed by the first developing device to a moving transfer medium and then transferring a toner image formed by the second developing device onto the transfer medium; a controller for selectively executing an operation in a first mode wherein the image is formed by both of the first developing device and the second developing device or in a second mode wherein the image is formed by only the second developing device

Abstract: An image forming apparatus includes an image forming device to form an image on a sheet and a sheet feeding unit to feed the sheet to the image forming device. The sheet feeding unit includes an endless, dielectric belt disposed facing an upper surface of a sheet stack to contact and attract an uppermost sheet to the surface thereof and feed the sheet in the sheet feeding direction, and an electric potential pattern forming unit to form an electric potential pattern on the surface of the dielectric belt. The electric potential pattern has multiple potential holding sections of identical absolute values and opposite polarities disposed adjacent to each other at a uniform pitch. The electric potential pattern forming unit forms the electric potential pattern to have equal numbers of positive potential holding sections and negative potential holding sections.

Abstract: An image forming apparatus includes a developing device for developing a latent image formed on an image bearing member into a developer image; a transferring device for transferring the developer image from the image bearing member onto a transfer material; a temperature detecting device, disposed in a main assembly of the image forming apparatus, for detecting a temperature; and a controller for controlling a forced consumption operation in which toner is forcedly consumed by the developing device without transferring the developer image from the image bearing member onto the transfer material.

Abstract: An image forming apparatus for performing image formation by using an electrophotographic process, the image forming apparatus including: a control section for judging existence of necessity of correction of process conditions in the electrophotographic process based on environment dependence characteristic information of a resistance value of a member that is used for the electrophotographic process and constitutes the image forming apparatus and environment change information in the own apparatus, and performing the correction based on the result of the judgment.

Abstract: The humidity detecting device includes a detection unit and a controller. The detection unit includes a humidity sensor for producing a humidity detection signal by detecting a humidity, a temperature sensor for producing a temperature detection signal by detecting a temperature surrounding the humidity sensor, and a common power supply line connected to the humidity sensor and the temperature sensor. The controller includes an application circuit for applying a power supply voltage to the humidity sensor and the temperature sensor through the common power supply line, a read circuit for producing a read-out humidity value corresponding to the humidity detection signal and a read-out temperature value corresponding to the temperature detection signal, and a correction circuit for correcting the read-out humidity value based on the read-out temperature value.

Abstract: A color image forming apparatus having photosensitive members; developing devices for developing electrostatic latent images formed on the photosensitive members into toner images with developers comprising toner and carriers; toner concentration sensors for detecting toner concentrations of the developers in the respective developing devices; a toner image bearing member for bearing the toner images temporarily; a toner adherence amount sensor for detecting toner adherence amounts of the toner images held on the image bearing member; and a controller for calculating, with respect to the developing devices, individual optimal developing bias voltage ranges within which a target toner adherence amount can be achieved while the toner concentrations of the developers are within a predetermined toner concentration range from a lower limit to an upper limit, so as to specify a common optimal developing bias voltage range that are commonly suitable for all the developing devices to achieve the target toner adherenc

Abstract: An image forming apparatus including a photosensitive member, a charging apparatus to charge a surface of the photosensitive member when applied with a charging voltage, and an exposure apparatus to expose the surface of the photosensitive member after being charged to form an electrostatic image. A developing apparatus attaches a developer to the electrostatic image and develop the electrostatic image as a developer image when applied with a development voltage. An environment measuring apparatus measures information regarding temperature and a time measuring apparatus measures information regarding a photosensitive member rotation time that represents a time during which the photosensitive member is rotated, and information regarding a photosensitive member stop time that represents a time during which the photosensitive member is stopped. A control apparatus controls an image formation condition based on a control mode.

Abstract: An image formation apparatus, an image formation method, an image formation program, and a computer-readable recording medium are provided, a rotation of the developer supply roller is controlled in order to prevent plugging of the developer supply roller based on quality information and environmental information.

Abstract: An image forming apparatus includes an image forming unit having an image carrier, a developing agent container for holding a developing agent, and a developing agent supplier for supplying the developing agent from the developing agent container to the image carrier. A controller determines the amount of use of the image forming unit. A shaking mechanism shakes the image forming unit from time to time, at intervals determined by the controller according to the amount of use of the image forming unit. The shaking loosens the developing agent so as to maintain its fluidity, thereby avoiding faint image formation.

Abstract: An image forming apparatus includes a belt member which bears a toner image, a transfer portion for forming a transfer nip portion, a changing unit for changing an advancing angle of the belt member advancing into the transfer nip portion, a guide member which is arranged at an upstream side of the transfer nip portion in a recording material conveying direction and face to a untransfered face of the recording material and guide a recording material to the transfer nip portion, and a controller for controlling the changing unit so that a belt face advancing into the transfer nip portion and conveying a recording material having a first thickness is at a position farther from the guide member than the belt face advancing into the transfer nip portion and conveying a recording material having a second thickness smaller than the first thickness.

Abstract: Systems and methods apply active feedback via a repetitive controller to compensate for periodic disturbances applied by recording media to a movable image carrier having a controlled velocity. The compensation parameters of the repetitive controller, once the error signal of the feedback converges to zero, can be stored with one or more characteristics of the print job or the recording media used for the print job. When other print jobs are received having the same one or more characteristics, the stored, converged compensation parameters can be retrieved, reducing the time to convergence of the systems and methods.

Abstract: According to an embodiment of the present invention, an image forming apparatus includes a toner image carrier that carries a toner image, a toner image detection sensor that detects a reference toner image on the toner image carrier, a temperature sensor that detects a temperature in the apparatus, and storage section for storing a correlation between each temperature and a drive value for the toner image detection sensor, in which calibration of the toner image detection sensor is performed by acquiring a corresponding drive value from the storage section based on the temperature measured by the temperature sensor and driving the toner image detection sensor at the acquired drive value.

Abstract: An image forming apparatus includes an image bearing member, a charging device to apply a charging bias, a developing device to develop a latent electrostatic image with toner, a transfer device to transfer the toner image to a recording medium, a fixing device to fix the toner image on the recording medium, an image formation speed switching device to switch from one image formation speed to another speed, a storage device to store a charging current target of the charging bias for each image formation speed, an electric current detection device to detect electric current flown through the charging device, and an AC voltage adjustment device to adjust AC voltage of the charging bias applied to the charging device. The charging current target is set for each of at least two image formation speeds such that each AC voltage adjusted by the AC voltage adjustment device is substantially the same.

Abstract: An image forming apparatus includes a rotatable drum; a charging roller, contacting the drum, for electrically charging the drum; a developing device for developing a latent image formed on the drum into a developer image; and a cleaning device for removing a developer remaining on the drum after the developer image is transferred from the drum onto a developer image receiving member. The cleaning device includes a cleaning blade contacting the drum and having a fixed end and a free end which is located upstream of the fixed end with respect to a rotational direction of the drum. The image forming apparatus further includes a control device for controlling a rotating operation of the drum.

Abstract: An image forming apparatus performs prints image data. A dividing section divides the image data of a print job into a plurality of sub data areas m(i) (i=1 to n). A duty computing section computes a print duty for each of the plurality of sub data areas (m(1)-m(n)) based on the number of printed dots in the print job and a total number of printable dots in a printable area. A first power supply applies a first voltage to a developing roller. A second power supply applies a second voltage to the developer supplying roller. The voltage difference between the first and second voltages is determined in accordance with the print duty.

Abstract: An image forming apparatus includes: a developer image carrier movably disposed; a developer image forming device configured to form a developer image; a detector configured to detect a density of the developer image formed on the developer image carrier; a controller configured to control an operation of forming of the developer image by the developer image forming device; an image forming unit configured to control the developer image forming device to form a density detection pattern including the same developer images at at least a first point and a second point with a predetermined distance therebetween; a density detector configured to obtain the density of the first point and the density of the second point of the density detection pattern via the detector; and a calculator configured to calculate a density difference between the first point and the second point based on the densities obtained by the density detector.

Abstract: Information (particularly, water content) of a sheet material which changes during progression of processing is estimated with higher accuracy and information output or (image formation) processing is performed. The water content estimation method of the present invention includes: detecting a first information regarding moisture contained in a sheet material; detecting a second information regarding a factor affecting information regarding the moisture contained in the sheet material; predicatively computing an estimation of a water content of the sheet material based on the first information and the second information; and adjusting processing conditions for image formation based on the estimation of the water content which is computed.