JP5760123B2 - Image forming apparatus and image forming method - Google Patents

Description

  The present invention relates to an image forming apparatus and an image forming method.

  2. Description of the Related Art There are known an image forming apparatus that forms an image using a erasable recording material (for example, toner) and an image erasing apparatus that can change an image from a colored state to a decolored state. In a erasable toner, erasing is performed by breaking the connection between the pigment and the color former by heating. In the conventional image erasing apparatus, in order to erase the toner image, for example, it is necessary to heat the paper at 120 to 150 ° C. for about 2 hours.

  As described above, the image forming apparatus and the image erasing apparatus have been provided as separate apparatuses for the reason that it takes about 2 hours for heating and about 1 hour for cooling as described above. It was.

JP 2005-205625 A

  However, purchasing and installing an image erasing apparatus separately from the image forming apparatus leads to a total cost increase. Therefore, when toner that can be erased in a short time can be used, the image forming function is combined with the image erasing apparatus to reduce the installation cost, and the image forming function and the image erasing function are the same apparatus. There is a need to configure the device so that it can be integrated within.

According to an embodiment for solving the above problems, an image forming unit that includes a decoloring recording material and a non-erasable recording material, and forms an image by switching between the decoloring recording material and the non-decoloring recording material; When an erasing operation is instructed, an operation setting unit that sets the operation of each unit so that the image forming unit operates in the erasing mode, and a supply unit that supplies a medium on which an image has been formed with the erasing recording material A heating unit that heats the medium supplied from the supply unit and erases an image formed on the medium in the decoloring mode; and a mode other than the decoloring mode during the decoloring mode. when a job is requested, the a state waiting for execution of the job until the job of the erasing mode is finished, the job of the erasing mode is finished then, depending on the recording material used by the image forming section , the jobs pending, before Or the temperature of the heating portion is performed after lowering the decoloring recording material lower predetermined temperature less than the temperature for decoloration, control for controlling whether to perform without waiting for the falling below the predetermined temperature And an image forming apparatus.

1 is a perspective view illustrating a schematic shape of an image forming apparatus according to a first embodiment. 1 is a configuration diagram illustrating a fixing device of an image forming apparatus according to a first embodiment. FIG. 2 is a block diagram illustrating a configuration of a control system of the image forming apparatus according to the first embodiment. FIG. 2 is an external view of a control panel provided in the image forming apparatus according to the first embodiment. 3 is a flowchart illustrating an image erasing operation of the image forming apparatus according to the first embodiment. It is a figure which shows the image decoloring operation screen displayed on the control panel of 1st Embodiment. 6 is a flowchart illustrating an image erasing operation of the image forming apparatus according to the second embodiment. 6 is a flowchart illustrating an image erasing operation of the image forming apparatus according to the second embodiment. It is a figure which shows the decoloring condition display screen in the image forming apparatus of 2nd Embodiment. It is a figure which shows the structure of the fixing device of the image forming apparatus of 6th Embodiment. It is a figure which shows the structure of the heating mechanism of the fixing device of the image forming apparatus of 6th Embodiment. It is a schematic block diagram of the image forming apparatus of 7th Embodiment. FIG. 20 is a configuration diagram illustrating an example of a configuration of a process unit of an image forming apparatus according to a seventh embodiment. It is a schematic block diagram of the image forming apparatus of 7th Embodiment.

[First Embodiment]
FIG. 1 is a perspective view illustrating a schematic shape of the image forming apparatus according to the first embodiment.
The image forming apparatus 1 includes a printing unit 130, a paper tray 200, a scanning unit 110, an auto feed unit 112, and a control panel 140.

  The print unit 130 outputs the image information as an output image called hard copy or printout, for example. The paper tray 200 supplies a recording medium, which is paper of an arbitrary size used for image output, to the printing unit 130. The scan unit 110 captures image information from the document as image data. The auto feed unit 112 sends the document that has been read from the reading position to the discharge position, and guides the next document to the reading position. The control panel 140 is an instruction input unit for instructing operations of the image forming apparatus 1 such as start of image formation in the print unit 130 and start of reading of image information of a document by the scan unit 110. The control panel 140 is provided with a display unit 141 for inputting instructions and displaying information to the operator.

  FIG. 2 is a configuration diagram illustrating the image forming unit 10 and the fixing device 26 of the image forming apparatus according to the first embodiment. The image forming apparatus 1 according to the first embodiment forms an image using toner whose color is erased by heating. The image forming apparatus 1 has a function of erasing the toner image.

  The photoconductive drum 11 of the image forming unit 10 includes an organic photoconductor (OPC) on the surface of a support member having a diameter of 60 mm. The photosensitive drum 11 is driven in the arrow S direction at a “first paper transport speed” peripheral speed of 215 mm / sec. Around the photosensitive drum 11, a charging charger 12, a laser exposure device 13, a developing device 14, a transfer charger 16, a peeling charger 17, a cleaner 18 having a cleaning blade 18a, and a static elimination LED 19 are arranged.

  The charging charger 12 uniformly charges the photosensitive drum 11 to -750V sequentially in accordance with the rotation of the photosensitive drum 11. The laser exposure device 13 irradiates the irradiation position 13b on the charged photosensitive drum 11 with a laser beam 13a corresponding to the image information.

  A sheet P as a recording medium is taken out from the sheet feeding cassette device 20 by a sheet feeding roller 21. In synchronization with the formation of the toner image on the photosensitive drum 11, the paper P is conveyed to the position of the transfer charger 16 of the image forming unit 10 by the registration roller 22. An unfixed toner image made of a decoloring toner is formed on the paper P by the image forming unit 10. The paper feeding cassette device 20 can feed both unused paper and reused paper.

  A fixing device 26 is disposed above the image forming unit 10. The fixing device 26 heat-presses and fixes the paper P that is a recording medium. The fixing device 26 includes a fixing roller 27 that is a fixing rotator, and a pressure roller 28 that is a pressure rotator that is in pressure contact with the fixing roller 27. The fixing device 26 has an entrance guide 26 a that guides the paper P to the nip between the fixing roller 27 and the pressure roller 28.

  The fixing roller 27 is configured by coating the surface of an iron hollow cylindrical cylinder with PTFE (polytetrafluoroethylene). The fixing roller 27 has an IH coil (induction heating coil) 30 inside. The fixing roller 27 is directly induction heated from the inside. The thermistor 31 detects the temperature of the surface of the fixing roller 27. The current of the IH coil 30 is controlled by the output of the thermistor 31, and the surface temperature of the fixing roller 27 is controlled to a predetermined temperature.

  The pressure roller 28 is formed by forming an elastic body layer made of foamed silicon sponge rubber or the like on a metal shaft and covering the surface with a PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer) tube. Yes. The hardness of the pressure roller 28 is about 55 ° in ASKER-C. The pressure roller 28 has a large nip of about 6 mm by an elastic layer to reduce the heat capacity for energy saving fixing.

  A paper discharge roller 32 that discharges the fixed paper P in a predetermined direction is provided downstream of the fixing device 26 in the conveyance direction of the paper P.

FIG. 3 is a block diagram illustrating a configuration of a control system of the image forming apparatus 1 according to the first embodiment.
The image forming apparatus 1 includes a control unit 100, a ROM, a DRAM, and an internal storage device (HDD) in addition to the above-described print unit 130, scan unit 110, and control panel 140. These units are connected via a system bus.

  The control unit 100 controls each unit connected via the system bus. The ROM stores various control programs necessary for the image forming apparatus 1 to operate. Each ROM stores programs for controlling an image forming operation and an image erasing operation, which will be described later. Execution of each program is controlled by the control unit 100. The DRAM is a buffer memory that temporarily stores data generated when each program is executed.

  FIG. 4 is an external view of the control panel 140 provided in the image forming apparatus according to the first embodiment. The control panel 140 is provided with a touch panel display 141 and an operation unit 170. The touch panel display 141 is configured by a touch panel, and displays the state of the image forming apparatus 1, operation procedures, various instructions for the user, and the like. The operation unit 170 is provided with various operation buttons including a start button for operating the image forming apparatus 1.

  For example, when the scan button 170a is pressed, the document can be scanned and image data can be acquired and stored in the DRAM of the image forming apparatus 1. When the copy button 170b is pressed, an image can be formed on the medium based on the acquired image data. When the fax button 170c is pressed, an image formed based on the acquired image data can be faxed. By operating the keyboard 170d, a numeric string can be input.

  Next, an image forming process by the image forming apparatus 1 will be described.

  At the start of the image forming process, in the image forming unit 10, the photosensitive drum 11 rotating in the direction of the arrow S at the “first paper conveyance speed” peripheral speed of 215 mm / sec is uniformly charged to −750 V by the charging device 12. . The photosensitive drum 11 is irradiated with laser light corresponding to document information by the laser exposure device 13 to form an electrostatic latent image. Next, the electrostatic latent image is developed by the developing device 14 using the color erasing toner, and a toner image made of the color erasing toner is formed on the photosensitive drum 11.

  In the first embodiment, a capsule-type thermally decolorable toner prepared by the following chemical method is used as the decolorable toner.

(1) Binder resin, WAX atomization liquid
A Pes resin was used as the binder resin. A resin atomization liquid was prepared using a high-pressure homogenizer using a Pes resin, an anionic emulsifier, and a neutralizing agent.

(2) Preparation of WAX dispersion
The atomized liquid was obtained by the same method as the above resin using rice WAX.

(3) Toner adjustment
Leuco dye: CVL (crystal violet lactone), developer: benzyl 4-hydroxybenzoate, temperature control agent: 4-benzyloxyphenylethyl laurate, heat-melted above, and encapsulated by well-known coacervation method did. The encapsulated colorant, the toner binder resin dispersion, and the WAX dispersion were agglomerated and fused using Al [Al2 (SO4) 3] sulfate, and further washed and dried to obtain a toner. External additives were appropriately added to the toner. This toner is hereinafter referred to as a capsule-type decoloring toner.

  The capsule-type decoloring toner used in the first embodiment was manufactured such that 10 wt% of the toner before applying the external additive was the amount of the encapsulated color material.

The developing device 14 uses a two-component developer which is a mixture of the above-described capsule-type decoloring toner having a volume average particle diameter of 5 to 12 μm and a magnetic carrier having a volume average particle diameter of 30 to 80 μm. The true specific gravity of the capsule-type decoloring toner is in the range of about 0.9 to 1.2 g / cm ³ . By heating the decolored toner image on the formed paper to 90 ° C. or higher, the bond between the dye and the color former in the capsule is broken by heating, and the color of the toner image is decolored. A developing bias of about −550 V is applied to the developing roller 14a of the developing device 14, and a toner image is formed on the electrostatic latent image on the photosensitive drum 11 by reversal development.

  On the other hand, the paper P is supplied from the paper feed cassette device 20. The sheet P is sent to the transfer charger 16 position by the registration roller 22 in synchronization with the formation of the toner image on the photosensitive drum 11, and the toner image on the photosensitive drum 11 is transferred.

  The paper P on which the toner image is transferred is peeled off from the photosensitive drum 11 and then sent to the fixing device 26. The surface temperature of the fixing roller is controlled to be 140 ° C. The paper P is inserted between the fixing roller 27 and the pressure roller 28, and the toner image is heated and pressed and fixed. Since the fixing roller 27 and the pressure roller 28 have a reverse crown shape, when the sheet P is inserted into the nip between the fixing roller 27 and the pressure roller 28, both ends of the sheet P are surely drawn earlier than the center. . Due to the reverse crown shape of the pressure roller 28, the sheet P is heated and pressed and fixed while being pulled from the center toward the end portion, thereby preventing the generation of wrinkles. After the fixing device 26 completes fixing the toner image with the capsule-type decoloring toner, the paper P is discharged in a predetermined direction by the paper discharge roller 32.

  After the transfer is completed, the photosensitive drum 11 is cleaned of residual toner by the cleaner 18, the residual charge is removed by the charge eliminating LED 19, and the image forming process is completed.

  At the “first paper conveyance speed” peripheral speed of 215 mm / sec, the temperature of the encapsulated color material did not exceed 90 ° C., and the color was not erased during image formation. However, the image density after fixing with the capsule-type decoloring toner in this example was an image density (0.3) that was barely acceptable in terms of visibility. Accordingly, it can be understood that the amount of the color material of the capsule-type decoloring toner is desirably 10 wt% or more in order to ensure the visibility of the image. In addition, the visibility of the image was evaluated using a measuring instrument (for example, X-rite).

  Next, a conventional image erasing process will be described.

  Until now, the color erasing of the capsule toner image has been performed by using, for example, a dedicated erasing device “T-E-HE (registered trademark) erasing device: TMD-HE01” manufactured by Toshiba Corporation. . In this apparatus, the paper P is heated at 120 to 150 ° C. for about 2 hours, and the color of the toner image is erased. Thereafter, automatic cooling was performed for about 1 hour. When the paper P from which the toner image has been erased is reused, the paper P that has been slightly stuck by heating is lightly separated and supplied to the paper feed cassette device 20 in order to peel it off. The reused paper P supplied to the paper cassette device 20 is used for image formation according to the image forming process. However, since the erasing by the erasing apparatus described above takes time, it has not been possible to reuse the paper immediately.

  In the first embodiment, the image is erased using the image forming apparatus 1 by taking advantage of the instantaneous decoloring property of the capsule decoloring toner.

FIG. 5 is a flowchart illustrating an image erasing operation of the image forming apparatus 1 according to the first embodiment.
The following operations are executed by the control unit 100 of the image forming apparatus 1.

The paper P on which an image is formed with the capsule-type decoloring toner is set in the paper feeding cassette device 20 in order to decolorize and reuse the toner image after the use is completed. The user performs an operation for image erasing. The paper P on which the image is formed may be set in a specific cassette device 20 or a manual feeding device.
In Act 01, the user sets the condition of the color erasing mode from the control panel 140.

  FIG. 6 is a diagram illustrating an image erasing operation screen 142 displayed on the control panel 140 according to the first embodiment.

  The user depresses an image erasing mode button from the image erasing operation screen 142, and further designates cassettes 1 to 4 as cassettes for paper supply, and a cassette in which paper P for reuse is stored from among manual feeds. . Here, the number of paper source cassettes is not limited to one, and a plurality of cassettes can be specified collectively. The user sets the number of sheets P to be erased. When the user inputs a numeric string from the keyboard 170d, the numeric string is displayed in the set number field 142a.

  When the user presses a start button provided on the operation unit 170 of the control panel 140, in Act 02, a decoloring mode (decoloring operation) is started. The image erasing operation screen 142 is not limited to this configuration, and may be configured by incorporating an operation button for image erasing into a conventional operation screen. Further, the paper P for reuse may be taken out from a specific cassette without designating the cassette.

  In Act 03, heating of the fixing roller 27 is started. In the first embodiment, the image forming apparatus 1 uses an erasing toner or a normal toner (not erasing) to perform an image forming operation. Therefore, in the printing mode (printing operation), the fixing roller temperature is controlled to be 100 ° C. or lower, for example, a set temperature of 80 ° C., and the toner image is not higher than 90 ° C. which is the decoloring temperature.

  Therefore, in Act 04, the fixing roller is heated until the temperature of the fixing roller becomes 140 ° C. or higher so that the decolorable toner is decolored. When the fixing roller temperature becomes 140 ° C. or more (YES in Act 04), the erasing operation is executed in Act 05.

  In the image erasing mode, the photosensitive drum 11 is driven in the arrow S direction at a “second paper transport speed” of a peripheral speed of 21 mm / sec. In the image erasing mode, an electrostatic latent image corresponding to image information from the laser exposure device 13 is not formed on the photosensitive drum 11. That is, the paper P is conveyed to the fixing device 26 through the same route as that in the above-described image formation.

  In the image erasing mode, the fixing device 26 also conveys the sheet while heating / pressing and fixing the sheet at a “second sheet conveying speed” of 21 mm / sec. The surface temperature of the fixing roller 27 at this time is the same 140 ° C. The toner image on the paper is heated to 90 ° C. or higher by heating the paper at a conveyance speed slower than that of the image forming process, and the color is erased by the instantaneous decoloring property of the capsule-type decoloring toner.

  In Act 06, at an appropriate timing, it is checked whether a new job request relating to the operation of the image forming apparatus is received during the decoloring operation. When there is no request for a new job (NO in Act 06), the process of Act 08 (described later) is executed. When there is a request for a new job (Yes in Act 06), a response corresponding to the type of the job is executed.

  When the image erasing operation is being performed, the image forming apparatus 1 according to the present embodiment waits for execution of a function that cannot be performed in parallel with the image erasing operation. On the other hand, a job that can be operated in parallel with the image erasing operation is executed.

  The job related to the operation of the image forming apparatus is, for example, a FAX reception job via a public line, a print job via a network, a scan job by an operation from the control panel 140, a copy job, a FAX transmission job, or the like.

  If the requested job is accompanied by a printing operation (image formation on a medium, fixing operation, etc.), the job is interrupted and processed as a reserved job. If the requested job is not accompanied by a printing operation, the job is allowed to be interrupted and executed as it is.

  In the above example, the print job via the network and the copy job by the operation from the control panel 140 are interrupt prohibited jobs. A FAX reception job via a public line, a scan job by an operation from the control panel 140, and a FAX transmission job are interruptible jobs.

  Note that the control panel 140 is provided with an interrupt button 170f for permitting an interrupt of the copy operation during printing or the like. However, during the decoloring operation, no interrupt operation is performed even if the interrupt button 170f is depressed. Not done.

  In Act 17, it is checked whether or not the job is an interrupt prohibited job. When the job is an interrupt-prohibited job (YES in Act 17), an image erasing operation is currently being executed. In Act 07, the job is reserved in a queue waiting for execution. When the job is not an interrupt-prohibited job (NO in Act 17), the job is executed.

  In Act 08, it is checked whether or not to end the erasing mode. For example, when the set number of media are erased, the erase mode is terminated. Also, when there is no medium in the set paper source cassette (when it becomes empty), the erasing mode is ended even if the set number of media are not erased.

  If it is not a condition for ending the erasing mode (NO in Act 08), the process returns to Act 05 to execute the erasing operation. When the erasing mode termination condition is satisfied (YES in Act 08), the erasing mode is terminated in Act 09. In Act 10, heating of the fixing roller 27 is stopped.

  In Act 11, it is checked whether or not the toner used in the image forming apparatus 1 is a decoloring toner. Whether or not the erasable toner is used is determined automatically by the image forming apparatus 1 by, for example, reading information about the toner (for example, whether or not it is the erasable toner and the erasable temperature) from a tag provided in the toner cassette. It may be determined, or the user may set from the control panel 140. Further, when it is unclear whether or not the erasing toner is used, it may be determined that the erasing toner is used.

When the decoloring toner is used (YES in Act 11), the process waits in Act 12 until the fixing roller temperature becomes 100 ° C. or less. When the fixing roller temperature becomes 100 ° C. or lower (YES in Act 12), it can be determined that the heating temperature in the fixing device 26 is equal to or lower than the temperature at which the color erasing toner does not erase. In Act 13, the print mode is started.
On the other hand, when the decoloring toner is not used (NO in Act 11), the printing mode is started in Act 13 without waiting until the fixing roller temperature becomes 100 ° C. or lower.

  In Act 14, execution of the reservation job is started.

  The predetermined temperature when waiting until the fixing roller temperature decreases to the predetermined temperature is information on the toner from the tag provided in the toner cassette (for example, whether the toner is a decolored toner, the decoloring temperature, etc.). May be automatically determined by the image forming apparatus 1, or may be set by the user from the control panel 140.

  As described above, in the first embodiment, when there is a new job request during the image erasing mode, if the job cannot be operated in parallel with the image erasing operation, the job is Wait for execution as a reserved job. Those JOBs are executed after the image erasing mode is completed and printing is possible. On the other hand, a job that can be operated in parallel with the image erasing operation is executed when requested.

  The image erasing screen 142 is provided with a forced end button for forcibly ending the image erasing mode. When this forced end button is operated, the image erasing mode is terminated and the mode is returned to a predetermined mode other than the image erasing mode (normal printing mode, Ready mode, energy saving mode, etc.). Even in this case, when there are reserved jobs in the image erasing mode, these jobs are executed after returning.

  In the above-described embodiment, the fixing roller 27 is heated, but the pressure roller 28 may be heated together. The sheet P is set in the sheet cassette 20 so that the surface on which the decoloring toner is printed is in direct contact with the fixing roller 27. However, the present invention is not limited to this form, and the back surface of the surface on which the decoloring toner is printed is fixed. It may be set in the paper cassette 20 so as to be in direct contact with the roller 27. By appropriately selecting the heating conditions such as the presence / absence of heating of the fixing roller 27 and the pressure roller 28, the heating temperature, the condition of the “second paper conveyance speed”, the thickness and type of the paper, An image erasing mode that does not depend on how the paper is placed can be set.

[Second Embodiment]
In the second embodiment, the first embodiment is to present (visualize) the degree of contribution to the environment obtained by erasing paper for reuse by using the image forming apparatus. The form is different. The same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  7 and 8 are flowcharts illustrating the image erasing operation of the image forming apparatus 1 according to the second embodiment.

  In Act 21, the user sets the decoloring mode condition from the control panel 140. The user presses the image erasing mode button from the image erasing operation screen 142 shown in FIG. 6, and cassettes 1 to 4 as paper source cassettes, and paper P for reuse from the manual feed are stored. Specify a cassette. Here, the number of paper source cassettes is not limited to one, and a plurality of cassettes can be specified collectively. Then, when the user presses a start button provided on the operation unit 170 of the control panel 140, in Act 22, a decoloring mode (decoloring operation) is started.

  In Act 23, heating of the fixing roller 27 is started. In Act 24, heating is performed until the fixing roller temperature is 140 ° C. or higher so that the decoloring toner is decolored. When the fixing roller temperature becomes 140 ° C. or higher (YES in Act 24), the erasing operation is executed in Act 25. Since this erasing operation is the same as that of the first embodiment, detailed description thereof is omitted.

  In Act 26, the number of sheets erased for each sheet size is counted up. In Act 27, the counted number of sheets is stored in the memory. In Act 28, the number of sheets erased in accordance with the decoloring operation is displayed.

  FIG. 9 is a diagram illustrating a decoloring status display screen 143 in the image forming apparatus according to the second embodiment.

  The decoloring status display screen 143 is provided with an image display area 143a and an information display area 143b. In the image display area 143a, a graphic 144a representing the image forming apparatus 1, a graphic 144b representing a cassette, and a graphic 144c representing an arrow are displayed. In the figure 144b representing the cassette, the size of the paper stored in each cassette is displayed, and the currently used cassette is displayed in different colors. In a figure 144c representing an arrow, the current position of the paper taken out from the cassette (cassette → image forming unit → fixing device → discharge unit) is displayed in a tracking manner in real time.

In the information display area 143b, the number of decolored sheets and the reduced amount of CO2 are displayed in real time according to the decoloring operation described above. The number of erased sheets is the number of sheets that have been erased since the start of the job. The reduced amount of CO2 is expressed by the following formula (1).
Reduced amount of CO2 = Reduced amount of CO2 per sheet x number of sheets erased
Reduced CO2 amount per sheet = CO2 amount necessary to manufacture one sheet−Energy (CO2 amount) required to erase one sheet (1)
In Act 29 of FIG. 7, it is checked at an appropriate timing whether a new job request relating to the operation of the image forming apparatus is received during the decoloring operation. When there is no request for a new job (NO in Act 29), the process of Act 31 (described later) is executed. When there is a request for a new job (Yes in Act 29), a response corresponding to the type of the job is executed.

  In Act 47, it is checked whether or not the job is an interrupt prohibited job. When the job is an interrupt-prohibited job (YES in Act 47), an image erasing operation is currently being executed. Therefore, in Act 30, the job is reserved in a queue waiting for execution. When the job is not an interrupt-prohibited job (NO in Act 47), the job is executed.

  In Act 31, it is checked whether or not to end the decoloring mode. If it is not a condition for ending the erasing mode (NO in Act 31), the process returns to Act 25 to execute the erasing operation. When the erasing mode termination condition is satisfied (YES in Act 31), the erasing mode is terminated in Act 32. In Act 33, the heating of the fixing roller 27 is stopped.

  In Act 34, it is checked whether or not the toner used in the image forming apparatus 1 is a decoloring toner. Whether or not the decoloring toner is used may be automatically determined by the image forming apparatus 1 by reading information on a tag provided in the toner cassette, or set by the user from the control panel 140. Also good. Further, when it is unclear whether or not the erasing toner is used, it may be determined that the erasing toner is used.

When the decoloring toner is used (YES in Act 34), the process waits in Act 35 until the fixing roller temperature becomes 100 ° C. or lower. When the fixing roller temperature becomes 100 ° C. or lower (YES in Act 35), it can be determined that the heating temperature in the fixing device 26 is equal to or lower than the temperature at which the color erasing toner does not erase. In Act 13, the print mode is started.
On the other hand, if the decoloring toner is not used (NO in Act 34), the printing mode is started in Act 36 without waiting until the fixing roller temperature becomes 100 ° C. or lower.

  In Act 40, execution of the reservation job is started. In Act 41, execution of the reservation job is terminated.

  When the user presses the erasing paper number display button on the image erasing operation screen 142 shown in FIG. 6 after the start of the printing mode of Act 36 (YES in Act 42), the cumulative erasing is performed on the control panel 140 in Act 43. The number of sheets is displayed. The accumulated number of erasable sheets is an accumulated value of the number of sheets erased from the initial time arbitrarily determined by the user to the present.

  The erasing status display screen 143 is not limited to the above-described form, and the number of erased sheets is counted for each standard paper size to display the total number of paper erasable sheets, or for each standard paper size. It is possible to display the total number of sheets that have been decolored for each time, or to display the amount of CO2 reduced by decoloring.

  As described above, in the second embodiment, the user can be motivated to contribute to the environment by visualizing the environmental contribution. In addition, it is possible to further motivate the user to contribute to the environment by returning the merit to the user according to the cumulative number of decolored sheets, the cumulative reduction CO2 amount, and the like.

[Third Embodiment]
The third embodiment is different from the first embodiment in that the sheet does not pass through the photosensitive drum 11 in the image erasing mode. Accordingly, the same parts as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The decoloring operation of the third embodiment will be described with reference to FIG.

  When erasing the toner image formed by the capsule-type erasing toner, the paper P is set in a paper feeding unit (not shown). When the start of the image erasing mode is input, the paper P is supplied to the paper path P2 without passing through the photosensitive drum 11. The paper P moves on the paper path P2, and is guided to the fixing device 26 by switching the gate 41. This conveyance speed is a “second paper conveyance speed” of 21 mm / sec, which is different from the “first paper conveyance speed” of 215 mm / sec during image formation, and the fixing device 26 also has a “second paper conveyance speed”. The paper is conveyed while being heated / pressure-fixed at 21 mm / sec.

  In the fixing device 26, the toner image on the paper P is heated. The connection between the dye and the color former is broken by heat, and the image changes from the colored state to the decolored state. Image erasing is completed when the color of the capsule toner image is erased. The paper P with the image erased is discharged in a predetermined direction by a paper discharge roller 32 disposed downstream of the fixing device 26 in the conveyance direction of the paper P. If this sheet is set again in the sheet feeding cassette device 20, it can be reused as a sheet for image formation.

  Note that the operating conditions of the fixing device 26 are the same as the operating conditions at the time of image erasing described in the first embodiment. Similarly to the first embodiment, during the image erasing mode, when a job of FAX, Print, or Copy is received, the image erasing mode is not interrupted, and those JOBs are displayed in the image erasing mode. A sequence is adopted in which printing of the JOB received during the image erasing mode is started after finishing (when there is no paper to be erased) and being ready for printing.

[Fourth Embodiment]
In the fourth embodiment, the amount of the color material of the capsule-type decoloring toner is different from that in the first embodiment. Accordingly, the same parts as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the fourth embodiment, the capsule-type decoloring toner is manufactured such that 30 wt% of the toner before adding the external additive is the amount of the encapsulated color material. The same test as described in the first embodiment was performed using capsule-type decoloring toners having different amounts of the color material.

  The obtained fixed image was an image with high image density and excellent visibility. However, in the image after the image erasing operation described in the first embodiment is executed to erase the color of the toner image, the color of the capsule itself remains unerased. The image density after erasing was 0.2, and the background noise was almost the allowable range for reusing paper. Therefore, in order to effectively erase the image, the amount of the color material of the capsule-type decoloring toner is desirably 30 wt% or less.

  According to the first embodiment, in order to ensure the visibility of the image, the amount of the color material of the capsule-type decoloring toner is desirably 10 wt% or more. According to the fourth embodiment, it is desirable that the amount of the color material of the capsule-type decoloring toner is 30 wt% or less in order for decolorization to function effectively. Therefore, the amount of the color material of the desirable capsule-type decoloring toner is considered to be 10 wt% to 30 wt%.

[Fifth Embodiment]
The fifth embodiment is different from the first embodiment in that the sheet is conveyed at the same conveyance speed as that at the time of image formation even during the decoloring operation. Accordingly, the same parts as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the fifth embodiment, the capsule-type decoloring toner is manufactured such that 30 wt% of the toner before adding the external additive is the amount of the encapsulated color material. When erasing the toner image formed by the capsule-type erasing toner, the paper P is set in the paper feeding cassette device 20. When the start of the image erasing mode is input, the photosensitive drum 11 of the image forming unit 10 is driven in the arrow s direction at the same “first paper conveyance speed” peripheral speed 215 mm / sec as that during image formation. .

  In the image erasing mode, an electrostatic latent image corresponding to image information from the laser exposure device 13 is not formed on the photosensitive drum 11. The paper P is transported to the fixing device 26 through a process similar to that at the time of image formation described above at a “first paper transport speed” peripheral speed of 215 mm / sec. In the image erasing mode, the fixing device 26 conveys the paper while heating / pressure-fixing the paper at a “second fixing temperature” 190 ° C., which is higher than the fixing temperature in the first embodiment. Under this condition, the toner image on the paper was heated to 90 ° C. or higher, and the paper P could be erased by the instantaneous decoloring property of the capsule-type decoloring toner.

  By the way, when the interval between sheets conveyed in the image erasing mode is set to about 80 mm, which is the same as the interval between sheets at the time of image formation, a phenomenon occurs in which the discharged sheets are adhered to each other by toner. This is because the temperature of the paper immediately after discharge is high, so that the toner resin sticks to the back side of the paper which is relatively soft and overlapped. Therefore, as a result of the test with the paper interval changed to various values, when the paper interval in the image erasing mode is about 400 mm, the discharged paper is pasted even if 100 sheets are continuously erased. There was no sticking. This is because the next sheet is discharged while the discharged sheet is cooled.

  From this, it can be seen that the phenomenon in which the sheets stick together can be avoided by changing the time interval for supplying the sheets to the fixing device 26 to about 2 seconds (≈400 / 215 seconds) or more.

[Sixth Embodiment]
In the sixth embodiment, the configuration of the fixing device is different from that of the first embodiment. Accordingly, the same parts as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 10 is a diagram illustrating a configuration of the fixing device 26 of the image forming apparatus 1 according to the sixth embodiment.

  The fixing device 26 includes a heat roller 51 that is a fixing member formed in a cylindrical shape, and a pressure belt 52 that is a pressure member that rotates endlessly. The pressure belt 52 is in contact with the outer peripheral surface of the heat roller 51 over a predetermined range to form a fixing nip portion. The heat roller 51 incorporates therein a heat roller lamp 53 composed of a halogen lamp as a heating source.

  The pressure belt 52 is wound and stretched around a belt heat roller 54 positioned on the upstream side in the transport direction, a pressure roller 55 positioned on the downstream side in the transport direction, and a tension roller 56. A fixing nip portion is formed between the belt heat roller 54 and the pressure roller 55. The pressure roller 55 brings the pressure belt 52 into pressure contact with the heat roller 51 to form the exit of the fixing nip portion. A pressure pad 58 is held by a pressure pad holder 57 disposed inside the pressure belt 52. The pressure belt 52 is pressed against the heat roller 51 by pressing the pressure pad 58 against the inner peripheral surface of the pressure belt 52 at the center of the fixing nip portion.

  The belt heat roller 54 is formed in a hollow roller shape and incorporates a pressure belt lamp 59 composed of a halogen lamp as a heating source.

  The surface temperature of the heat roller 51 is detected by the fixing member thermistor 61 in contact with the outer peripheral surface, and the surface temperature of the pressure belt 52 in the belt heat roller 54 is detected by the pressure member thermistor 62 in contact with the outer peripheral surface.

  FIG. 11 is a diagram illustrating a configuration of a heating mechanism of the fixing device 26 of the image forming apparatus 1 according to the sixth embodiment. FIG. 11 shows a heating mechanism inside the fixing device 26 and an energization control unit 50 that controls energization of the heating mechanism.

  The halogen lamp 53 incorporated in the heat roller 51 includes a heat roller center lamp 53A that heats the longitudinal center portion of the heat roller 51 and a heat roller side lamp 53B that heats both longitudinal ends of the heat roller 51. Has two. The pressure belt lamp 59 built in the belt heat roller 54 heats the belt heat roller 54 over the entire length in the length direction.

  The heat roller center lamp 53A, the heat roller side lamp 53B, and the pressure belt lamp 59 are electrically connected to the center lamp switching element 63A, the side lamp switching element 63B, and the pressure belt lamp switching element 64, respectively. . The temperature controller 65 controls ON / OFF of these switching elements individually, thereby supplying / stopping commercial AC power and controlling the temperature. These switching elements can use bidirectional thyristors, for example.

  The fixing member thermistor 61 includes a heat roller center thermistor 61 </ b> A that detects the surface temperature of the central portion in the length direction of the heat roller 51, and a heat roller that detects the surface temperature of one end portion in the length direction of the heat roller 51. Side thermistor 61B. The temperature detection information of the heat roller center thermistor 61 </ b> A and the heat roller side thermistor 61 </ b> B is input to the temperature controller 65. The pressure member thermistor 62 detects the surface temperature of the central portion in the width direction of the pressure belt 52. The temperature detection information is input to the temperature controller 65.

  The temperature controller 65 performs temperature control by controlling ON / OFF of each lamp based on the temperature detection information of each thermistor 61A, 61B, 62. The temperature controller 65 includes a ROM (not shown) that stores a program for executing temperature control and a RAM (not shown) that stores temperature control control parameters.

[Seventh Embodiment]
In the seventh embodiment, the configuration of the image forming apparatus is different from that of the first embodiment. Accordingly, the same parts as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 12 is a schematic configuration diagram of an image forming apparatus according to the seventh embodiment. The image forming apparatus 1 is an image forming apparatus using a multiple tandem process. The image forming apparatus 1 includes a multiple tandem process 120, a blade 112 (toner removing unit), a control device 114, a paper feeding device 115, a primary transfer belt 116, a secondary transfer roller 117, and a fixing device 26. The multiple tandem process 120 has four process units 121, 122, 123, and 124.

  The process units 121, 122, 123, and 124 use yellow (Y) toner, magenta (M) toner, cyan (C) toner, and decoloring toner. That is, in the seventh embodiment, it is possible to switch between the decolored toner and the non-erasable toner without replacing the toner cassette.

  FIG. 13 is a configuration diagram illustrating an example of the configuration of the process unit 121 of the image forming apparatus according to the seventh embodiment. The process unit 121 includes a developing device 121a, a photosensitive drum 121b, a charging device 121c, and an exposure device 121d.

  In the process unit 121, the photosensitive drum 121b (image carrier) is charged to a predetermined potential by the charging device 121c and irradiated with a laser beam whose intensity is modulated by image information by the exposure device 121d. Thereby, an electrostatic latent image corresponding to the image to be output is formed on the photosensitive drum 121b. The electrostatic latent image formed on the photoconductive drum 121b is developed by selectively providing toner by the magnetic brush of the developing device 121a. The developed toner on the photosensitive drum 121b is transferred to the primary transfer belt 116 by an electric field. The process unit 121 is a cleanerless type, but is not limited to this type, and may include a cleaner. The configurations and operations of the other process units 122, 123, and 124 are the same.

  In the image forming apparatus 1 shown in FIG. 12, each color toner is transferred to the primary transfer belt 116 through an image forming process by the process units 121, 122, 123, and 124. Thereafter, the paper is discharged from the image forming apparatus 1 through a paper feed, a secondary transfer process by the secondary transfer roller 117, and a fixing process by the fixing device 26.

  Note that the image forming apparatus 1 is not limited to the configuration illustrated in FIG. 12, and may be configured as illustrated in FIG. The image forming apparatus 1 shown in FIG. 14 includes a multiple tandem process 140 instead of the multiple tandem process 120. The double tandem process 140 includes, for example, a process unit 141 that uses decolored toner and a process unit 142, 143, 144, and 145 that uses non-decolorable toner of four colors (Y, M, C, K). Composed.

  The image forming apparatus according to each embodiment has been described above. In the image erasing mode, the paper conveyance speed is made slower or the fixing temperature is made higher than in image formation. In the image erasing mode, operation is performed at a predetermined second paper conveyance speed or operation condition of the second fixing temperature. However, it is conceivable that these operating conditions in the image erasing mode have different appropriate values depending on the medium used (type and thickness), the physical properties of the toner used, and the like.

  Therefore, for example, the operating conditions in the image erasing mode are switched by detecting the characteristics (type and thickness) of the medium to be used and the physical properties (decoloring performance) of the toner to be used or obtained by user setting input. May be. At that time, the following operation methods can be appropriately combined depending on the operation conditions.

(1) In the image erasing mode, the second conveyance speed, which is lower than the sheet conveyance speed, is set in the conveyance control system as compared with the image forming mode. (2) In the image erasing mode, a second fixing temperature is set in the fixing device, the fixing temperature being higher than that in image formation. (3) In the image erasing mode, the second conveyance speed at which the sheet conveyance speed is set lower than that at the time of image formation is set in the conveyance control system, and the second fixing temperature at which the fixing temperature is increased is set as the fixing device. Set to.

  In each of the above-described embodiments, the thermally erasable toner is used as the thermally erasable recording material. However, the present invention is not limited to this mode, and the thermally erasable ink may be used.

  Each function described in the above embodiment may be configured using hardware, or may be realized by reading a program describing each function into a computer using software. Each function may be configured by appropriately selecting either software or hardware.

  Furthermore, each function can be realized by causing a computer to read a program stored in a recording medium (not shown). Here, as long as the recording medium in the present embodiment can record a program and can be read by a computer, the recording format may be any form.

Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage.
Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.
Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage.
Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.
Hereinafter, the invention described in the scope of claims of the present application will be appended.
[1] When an erasing operation is instructed, an operation setting unit that sets the operation of each unit so that the image forming apparatus operates in the erasing mode, and a thermal erasing unit set in at least one designated storage unit. A supply unit that supplies a medium on which an image is formed with a colorable recording material, a heating unit that heats the medium and erases the formed image in the color erasing mode, and the color erasing mode during the color erasing mode. When a job in a mode other than the color erasing mode is requested, a control unit that executes the job in the waiting state after the job in the color erasing mode is ended after waiting for execution of the job. An image forming apparatus.
[2] The image forming apparatus according to [1], further including a display unit that displays at least the number of media erased by the heating unit for each size of the media.
[3] When the recording material used in the image forming apparatus is a heat erasable recording material, the control unit finishes erasing the medium and the temperature of the heating unit erases the image. The image forming apparatus according to [1] or [2], wherein the job in a waiting state is executed after the temperature falls below a predetermined temperature lower than a color temperature.
[4] Additional note [3], further comprising a reading unit that reads information on the recording material from a tag provided in the recording material cassette, wherein the predetermined temperature of the heating unit is obtained based on the information on the recording material. The image forming apparatus described in 1.
[5] When the recording material used in the image forming apparatus is not a thermally erasable recording material, the control unit executes the job in a waiting state after the erasing of the medium is completed. The image forming apparatus according to appendix [1] or [2].
[6] When the erasing operation is instructed, the operation of each unit is set so that the image forming apparatus operates in the erasing mode, and the recording that is set in at least one designated storage unit is capable of thermal erasing. When an image-formed medium is supplied with a material, the medium is heated to erase the formed image, and a job in a mode other than the erase mode is requested during the erase mode, An image forming method of waiting for execution of the job and executing the job in the waiting state after the job in the erasing mode is completed.

  DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 10 ... Image forming part, 11 ... Photoconductor drum, 12 ... Charger charger, 13 ... Laser exposure apparatus, 14 ... Developing apparatus, 16 ... Transfer charger, 17 ... Stripping charger, 18 ... Cleaner, 19 ... Static elimination LED, 20 ... feed cassette device, 21 ... feed roller, 22 ... registration roller, 26 ... fixing device, 27 ... fixing roller, 28 ... pressure roller, 30 ... IH coil, 31 ... thermistor, 32 ... discharge Roller, 100 ... Control unit, 110 ... Scanning unit, 112 ... Auto feed unit, 130 ... Printing unit, 140 ... Control panel, 141 ... Display unit, 141 ... Touch panel display, 50 ... Power supply control unit, 51 ... Heat roller, 52 ... Pressure belt, 53 ... Heat roller lamp, 53 ... Halogen lamp, 54 ... Belt heat roller, 55 ... Pressure Over la, 56 ... tension roller, 58 ... pressure pad, 61 ... fixing member thermistor, 62 ... pressure member thermistor, 65 ... temperature controller, 120 ... double continuous tandem process, 140 ... double continuous tandem process.

Claims (5)

An image forming unit comprising an erasable recording material and a non-erasable recording material, and forming an image by switching between the erasable recording material and the non-erasable recording material;
An operation setting unit that sets the operation of each unit so that the image forming apparatus operates in the color erasing mode when an erasing operation is instructed;
A supply unit for supplying a medium on which an image has been formed with the decoloring recording material;
In the color erasing mode, a heating unit that heats the medium supplied from the supply unit and erases an image formed on the medium;
When a job in a mode other than the color erasing mode is requested during the color erasing mode , execution of the job is waited until the job in the color erasing mode is completed , and the job in the color erasing mode is Upon completion, the job in the waiting state is reduced to a predetermined temperature lower than the temperature for erasing the erasable recording material , depending on the recording material used in the image forming unit. A control unit for controlling whether to execute the operation without waiting for the temperature to fall below the predetermined temperature ;
An image forming apparatus. When the recording material used in the image forming unit is the erasable recording material, the control unit performs the job in the waiting state, and the temperature of the heating unit erases the erasable recording material. And after the temperature is lowered to a predetermined temperature lower than the predetermined temperature, when the non-erasable recording material, the job in the waiting state is executed without waiting for the temperature to fall below the predetermined temperature.
The image forming apparatus according to claim 1. When it is unclear whether the recording material used in the image forming unit is the erasable recording material or the non-erasable recording material, the control unit determines the job in the waiting state as the temperature of the heating unit. Executed after the temperature of the decoloring recording material is lowered below a predetermined temperature lower than the temperature for decoloring.
The image forming apparatus according to claim 2 . A reading unit that reads information about the recording material used in the image forming unit from a tag provided in a cassette that accommodates the erasing recording material and the non-erasing recording material ,
The image forming apparatus according to claim 1 , further comprising: An image forming method of an image forming apparatus, comprising an erasable recording material and a non-erasable recording material, and forming an image by switching between the erasable recording material and the non-erasable recording material,
When the erasing operation is instructed, the operation of each unit is set so that the image forming apparatus operates in the erasing mode,
In the erasing mode, supplying an image-formed medium with the erasing recording material, heating the supplied medium with a heating unit, and erasing the image formed on the medium,
When a job in a mode other than the color erasing mode is requested during the color erasing mode , execution of the job is waited until the job in the color erasing mode is completed , and the job in the color erasing mode is Upon completion, the job in the waiting state is reduced to a predetermined temperature lower than the temperature for erasing the erasable recording material , depending on the recording material used in the image forming apparatus. To control whether to execute after waiting, or without waiting for the temperature to fall below the predetermined temperature ,
Image forming method.

Images