JP2013088665A - Heating device, image forming apparatus and post-processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heating device, an image forming apparatus and a post-processing device capable of imparting gloss to an optional region while reducing costs.SOLUTION: A heating device comprises: a thermal head 70 for heating paper P fixed by a fixing device 60 which causes paper S carrying a toner image to enter a nip part, which is formed by a heating rotary body and a pressing rotary body crimping to the heating rotary body, to fix the toner image by heating and pressing; and a control part 80 for controlling the thermal head 70 so as to heat an optional region of paper S1 (for example, a region of a photographic image). Thus, unlike prior arts, since the region of a photographic image of the paper S1 can be partially and selectively re-heated (re-fixed) without using a gloss imparting agent, gloss can be imparted to the region of a photographic image while reducing costs. The heating device is especially preferably used for the production print market requiring image quality comparable to offset printing.

Description

  The present invention relates to a heating apparatus, an image forming apparatus, and a post-processing apparatus that adjust the glossiness of an image formed by an electrophotographic process.

  In general, in an image forming apparatus that forms an image by an electrophotographic process, the surface of an image carrier (photosensitive drum or the like) is charged to a predetermined potential, and this is subjected to image exposure to form an electrostatic latent image. Then, the latent image on the surface of the photosensitive drum is developed by a developing unit using a developer (toner) and visualized as a toner image. The obtained toner image is transferred to a sheet conveyed to a photosensitive drum, the sheet carrying the toner image is conveyed to a fixing device, and the unfixed toner image on the sheet is heated and fixed by the fixing device, and the image is formed on the sheet. Is formed.

  By the way, depending on the toner image formed on the paper, there is a case where it is desired to divide the region and give different glossiness. For example, it is preferable that the gloss of a photographic image is higher than that of a character image.

  Conventionally, a technique for partially and selectively imparting a desired gloss to a specific region of a toner image has been proposed (see, for example, Patent Document 1). In this technique, a second fixing device is further provided on the downstream side of a fixing device provided in a normal image forming process, and a specific gloss of a toner image is partially and selectively reheated to obtain a desired glossiness. Is a technology that gives

JP 2007-52175 A

  However, in the technique described in Patent Document 1, the glossiness is improved by applying a gloss imparting agent (transparent toner) before performing the heat fixing process. That is, since the gloss is imparted using the gloss imparting agent, there is a problem that the cost is increased.

  An object of the present invention is to provide a heating apparatus, an image forming apparatus, and a post-processing apparatus capable of imparting gloss to an arbitrary region while reducing cost.

A heating device according to the present invention includes a heating unit that heats a toner image fixed on a sheet,
And a control unit that controls the heating unit so as to heat an arbitrary area of the sheet.

An image forming apparatus according to the present invention includes a heating unit that heats a toner image fixed on a sheet,
And a control unit that controls the heating unit so as to heat an arbitrary area of the sheet.

A post-processing apparatus according to the present invention is a post-processing apparatus that can be connected to an image forming apparatus that forms a toner image on a sheet and performs predetermined post-processing on the sheet.
A heating unit that heats a toner image fixed on the paper, the heating unit controlled by a control unit to heat an arbitrary area of the paper, the paper supplied from the image forming apparatus It is provided so that it may heat.

  According to the present invention, it is possible to provide a heating apparatus, an image forming apparatus, and a post-processing apparatus capable of giving gloss to an arbitrary region while reducing cost.

1 is a longitudinal sectional view of an image forming apparatus showing a first embodiment according to the present invention. 1 is a control block diagram of an image forming apparatus showing a first embodiment according to the present invention. It is a figure explaining the operation example of the image forming apparatus which shows the 2nd Embodiment concerning this invention. It is a figure explaining the operation example of the image forming apparatus which shows the 3rd Embodiment concerning this invention. It is a longitudinal cross-sectional view of the post-processing apparatus which shows the 1st-3rd embodiment which concerns on this invention.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. An image forming apparatus 1 shown in FIG. 1 is an intermediate transfer type color image forming apparatus using electrophotographic process technology. That is, the image forming apparatus 1 transfers (primary transfer) each color toner image of C (cyan), M (magenta), Y (yellow), and K (black) formed on the photosensitive member to the intermediate transfer member, An image is formed by superimposing four color toner images on the intermediate transfer member and then transferring (secondary transfer) to a sheet.

  In addition, the image forming apparatus 1 employs a tandem system in which photoconductors corresponding to four colors of CMYK are arranged in series in the running direction of the intermediate transfer member, and each color toner image is sequentially transferred to the intermediate transfer member in one procedure. Has been.

  As shown in FIG. 1, the image forming apparatus 1 includes an image reading unit 10, an operation display unit 20, an image processing unit 30, an image forming unit 40, a conveyance unit 50, a fixing device 60, a thermal head 70 that functions as a heating unit, And a control unit (not shown). The thermal head 70 and the control unit function as a heating device.

  The control unit includes an arithmetic device such as a CPU (Central Processing Unit), and controls the image forming apparatus 1 by executing a predetermined control program on the CPU. The control unit controls the image forming operation of the image forming apparatus 1 according to the job information input from the operation display unit 20.

  The image reading unit 10 includes an automatic document feeder 11 called an ADF (Auto Document Feeder), a document image scanning device (scanner) 12, and the like. The automatic document feeder 11 transports the document D placed on the document tray by a transport mechanism and sends it out to the document image scanning device 12. The automatic document feeder 11 can continuously read images (including both sides) of a large number of documents D placed on a document tray all at once.

  The document image scanning device 12 optically scans a document conveyed on the contact glass from the automatic document feeder 11 or a document placed on the contact glass, and reflects light from the document to a CCD (Charge Coupled Device). ) An image is formed on the light receiving surface of the sensor 12a, and an original image is read. The image reading unit 10 generates input image data based on the reading result by the document image scanning device 12. The input image data is subjected to predetermined image processing in the image processing unit 30.

  The operation display unit 20 is configured by, for example, a liquid crystal display (LCD) with a touch panel, and functions as the display unit 21 and the operation unit 22. The display unit 21 displays various operation screens, an image status display, an operation status of each function, and the like according to a display control signal input from the control unit. Various operations and input operations for setting can be performed on the operation unit 22. The instruction / setting information is handled by the control unit as job information. The job information includes a paper size, the number of prints, and the like.

  The image processing unit 30 includes a circuit that performs digital image processing corresponding to initial settings or user settings on input image data. For example, the image processing unit 30 performs tone correction based on tone correction data (tone correction table) under the control of the control unit. Further, the image processing unit 30 performs various correction processes such as color correction and shading correction, a compression process, and the like on the input image data in addition to the gradation correction. The image forming unit 40 is controlled based on the image data subjected to these processes.

  Further, the image processing unit 30 discriminates a region of the photographic image from the input image based on the input image data by using a known image recognition technique, and position information indicating the position (in the input image) of the discriminated region. Output to the control unit. In the present embodiment, the image processing unit 30 determines that the area is a photographic image area when the number of colors included in the area having a predetermined area is equal to or greater than a predetermined value.

  The image forming unit 40 includes image forming units 41Y, 41M, 41C, and 41K, and an intermediate transfer unit for forming an image using colored toners of Y component, M component, C component, and K component based on input image data. 42 etc. are provided.

  The Y component, M component, C component, and K component image forming units 41Y, 41M, 41C, and 41K have the same configuration. For convenience of illustration and explanation, common constituent elements are denoted by the same reference numerals, and when distinguished from each other, Y, M, C, or K is added to the reference numerals. In FIG. 1, only the components of the Y-component image forming unit 41Y are denoted by reference numerals, and the constituent elements of the other image forming units 41M, 41C, and 41K are omitted.

  The image forming unit 41 includes an exposure device 411, a developing device 412, a photosensitive drum 413, a charging device 414, a drum cleaning device 415, and the like.

  The photosensitive drum 413 has, for example, an undercoat layer (UCL), a charge generation layer (CGL), a charge transport layer (CGL) on the peripheral surface of an aluminum conductive cylinder (aluminum tube). It is a negatively charged organic photoreceptor (OPC: Organic Photo-conductor) in which CTL (Charge Transport Layer) is sequentially laminated.

  The charging device 414 uniformly charges the surface of the photoconductive drum 413 to a negative polarity. The exposure device 411 is composed of, for example, a semiconductor laser, and irradiates the photosensitive drum 413 with laser light corresponding to the image of each color component. A positive charge is generated in the charge generation layer of the photosensitive drum 413 and is transported to the surface of the charge transport layer, whereby the surface charge (negative charge) of the photosensitive drum 413 is neutralized. An electrostatic latent image of each color component is formed on the surface of the photosensitive drum 413 due to a potential difference from the surroundings.

  The developing device 412 contains a developer of each color component (for example, a two-component developer composed of a toner having a small particle diameter and a magnetic material), and causes the toner of each color component to adhere to the surface of the photosensitive drum 413. Thus, the electrostatic latent image is visualized to form a toner image. The drum cleaning device 415 includes a drum cleaning blade that is in sliding contact with the surface of the photosensitive drum 413. Transfer residual toner remaining on the surface of the photosensitive drum 413 after the primary transfer is scraped off and removed by a drum cleaning blade.

  The intermediate transfer unit 42 includes an intermediate transfer belt 421 serving as an intermediate transfer member, a primary transfer roller 422, a secondary transfer roller 423, a driving roller 424, a driven roller 425, a belt cleaning device 426, and the like.

  The intermediate transfer belt 421 is an endless belt, and is stretched around the driving roller 424 and the driven roller 425. The intermediate transfer belt 421 travels at a constant speed in the direction of arrow A by the rotation of the driving roller 424. When the intermediate transfer belt 421 is pressed against the photosensitive drum 413 by the primary transfer roller 422, the toner images of the respective colors are sequentially superimposed on the intermediate transfer belt 421 and primarily transferred. When the intermediate transfer belt 421 is pressed against the sheet S by the secondary transfer roller 423, the toner image primarily transferred to the intermediate transfer belt 421 is secondarily transferred to the sheet S.

  The belt cleaning device 426 includes a belt cleaning blade that is in sliding contact with the surface of the intermediate transfer belt 421. Transfer residual toner remaining on the surface of the intermediate transfer belt 421 after the secondary transfer is scraped off and removed by a belt cleaning blade.

  The fixing device 60 fixes the toner image on the paper S by heating and pressurizing the conveyed paper S at the nip portion. The fixing device 60 is an air separation type fixing device including a fixing unit 61 and an air separation unit 62.

  The transport unit 50 includes a paper feed unit 51, a transport mechanism 52, a paper discharge unit 53, and the like. In the three paper feed tray units 51a to 51c constituting the paper feed unit 51, paper (standard paper, special paper) S identified based on the basis weight, size, etc. of the paper is stored for each preset type. Is done.

  The sheets S accommodated in the sheet feed tray units 51a to 51c are sent one by one from the top, and are conveyed to the image forming unit 40 by a conveyance mechanism 52 having a plurality of conveyance rollers such as a registration roller 52a. At this time, the registration section provided with the registration rollers 52a corrects the inclination of the fed paper S and adjusts the conveyance timing. In the image forming unit 40, the toner image on the intermediate transfer belt 421 is secondarily transferred to one side of the sheet S at a time, and a fixing process is performed in the fixing device 60. The sheet S on which the image has been formed is discharged out of the apparatus by a discharge unit 53 having a discharge roller 53a.

  The thermal head 70 is disposed on the downstream side of the fixing device 60 in the conveyance direction of the paper S, and has a plurality of heating elements arranged linearly in the width direction of the paper S (direction perpendicular to the conveyance direction of the paper S). . The plurality of heating elements are arranged at a density of 300 [dpi (dot per inch)], for example. The thermal head 70 heats the sheet S on which the toner image is fixed by the fixing device 60 under the control of the control unit.

  Since the thermal head 70 has different toner image fixing properties depending on the type of the paper S, it is preferable to change the amount of heat supplied when the paper S is heated. For example, when the paper S is a thick paper, the thermal capacity of the thick paper is large, so the thermal head 70 heats the paper S with a high amount of supplied heat. On the other hand, when the paper S is a thin paper, since the heat capacity of the thin paper is small, the thermal head 70 heats the paper S with a low supply heat amount.

  Based on the position information output from the image processing unit 30, the control unit controls to heat the region of the photographic image (the region corresponding to “arbitrary region” in the claims) on the fixed sheet S. To do. As a result, on the paper S on which the toner image is formed, gloss is further imparted only to the photographic image area.

  Next, a control block diagram of the image forming apparatus 1 will be described with reference to FIG. As shown in FIG. 2, the image forming apparatus 1 includes a fixing device 60, a thermal head 70, and a control unit 80.

  The control unit 80 includes a CPU 90, a ROM (Read Only Memory) 91, a RAM (Random Access Memory) 92, and a thermal drive unit 93.

  The CPU 90 reads a specified program from the system programs and various application programs stored in the ROM 91, expands them in the RAM 92, executes various processes in cooperation with the programs expanded in the RAM 92, and forms an image. Each part of the apparatus 1 is controlled.

  The ROM 91 stores various programs executed by the CPU 90. The RAM 92 is a volatile memory, has a work area for storing various programs executed by the CPU 90 and data related to these various programs, and temporarily stores the information. In the present embodiment, the RAM 92 temporarily stores the position information output from the image processing unit 30.

  The thermal driving unit 93 receives the control signal output from the CPU 90 and controls the driving of the thermal head 70. Specifically, the thermal drive unit 93 controls to heat the photographic image area on the sheet S on which the toner image is fixed by the fixing device 60 based on the position information stored in the RAM 92. As a result, on the paper S on which the toner image is formed, gloss is further imparted only to the photographic image area.

  As described above in detail, in the first embodiment, the thermal head 70 that heats the toner image fixed on the paper S and the thermal head that heats an arbitrary area (photograph image area) of the paper S. And a control unit 80 for controlling the head 70.

  According to the first embodiment configured as described above, unlike the conventional technique, the region of the photographic image on the paper S is partially and selectively reheated (refixed) without using a gloss imparting agent. Therefore, it is possible to give gloss to the region of the photographic image while reducing the cost. In particular, in the production print market where the output image itself is a product and image quality equivalent to that of offset printing is required, it is preferable to use the image forming apparatus 1 that exhibits the above effects.

  In the first embodiment, as a means for reheating the paper S, the thermal head 70 that reaches the heating temperature in a short time and can control the supply heat amount with high accuracy is employed. As a result, it is possible to perform a process of selectively applying gloss to a desired area as much as necessary with high accuracy.

(Second Embodiment)
The second embodiment is a modification of the control operation for the thermal head 70 of the control unit 80 described in the first embodiment. FIG. 3 is a diagram for explaining an operation example of the image forming apparatus 1 according to the second embodiment of the present invention. This embodiment is different from the first embodiment in that the thermal head 70 is controlled so as to partially heat a region on the paper S where the fixing temperature of the toner image is lower than a predetermined temperature.

  The purpose of performing the above operation is as follows. That is, when the peripheral length of the endless fixing belt provided in the fixing device 60 is shorter than the length in the conveyance direction of the paper S, the same point of the fixing belt passes twice or more on the same surface of the paper S. In this case, the heat of the fixing belt taken away by the entry of the sheet S cannot be recovered by the second round, and a temperature difference between the first and second rounds (temperature difference of the surface temperature of the fixing belt). ) Occurs. When this temperature difference is large, there arises a problem that uneven gloss (gloss level difference) occurs in the toner image on the paper S.

  As a measure for solving this problem, it is conceivable to make the peripheral length of the fixing belt longer than the length of the paper S in the conveyance direction. However, other problems such as an increase in equipment cost, an increase in power consumption of the fixing belt, and an increase in the size of the fixing device occur, which cannot be said to be an effective measure for solving the above problems. As another countermeasure, it is conceivable to perform a heat design so that the temperature does not decrease even if the fixing belt makes two or more turns on the same surface of the paper S. However, another problem arises that the heat cycle design in the fixing unit 16 is complicated and the design cost is increased, which is not an effective measure for solving the above problem.

  Therefore, in the second embodiment according to the present invention, the following configuration is adopted to prevent the occurrence of uneven gloss (gloss level difference) due to the temperature difference of the surface temperature of the fixing belt.

  In the second embodiment, the belt 91 information indicating the circumference of the fixing belt is stored in advance in the ROM 91 of the controller 80.

  As shown in FIG. 3A, the thermal drive unit 93 of the control unit 80 includes belt circumference information held in the ROM 91 when the paper S passes through the thermal head 70 in the arrow direction (conveyance direction), and An area related to the second round of the fixing belt on the paper S based on the paper size included in the job information input by the operation display unit 20 (the information corresponds to “area information” in the claims). The thermal head 70 is controlled to heat B. In the region B, the heat of the fixing belt taken away by the entry of the region A of the paper S cannot be recovered by the second round, and the fixing temperature when the toner image is fixed by the fixing device 60 is lower than a predetermined temperature. It is an area.

  Specifically, the thermal driving unit 93 is a value obtained by subtracting the belt circumferential length from the paper size (the position of the boundary between the region A related to the first rotation of the fixing belt and the region B related to the second rotation on the paper S). To the rear end position in the transport direction of the paper S is identified as a region B. Then, the thermal drive unit 93 heats the toner image fixed on the paper S at the timing when the region B of the paper S passes through the thermal head 70 while considering the conveyance speed of the paper S.

  FIG. 3B is a diagram showing the relationship between the distance from the leading edge in the transport direction of the paper S and the amount of heat supplied at the time of heating when the thermal head 70 heats the toner image fixed on the paper S. is there. As shown in FIG. 3B, the thermal drive unit 93 has a large amount of heat supply at the timing (switching timing) at which the region A on the first rotation of the fixing belt switches from the region A on the first rotation to the region B on the second rotation. Thus, the thermal head 70 is controlled. The amount of heat is also supplied to the area A (the area where the fixing temperature is equal to or higher than the predetermined temperature) related to the first round of the fixing belt on the sheet S in the area B related to the second round of the fixing belt. This is because a warm-up process is required to prepare for heating to supply a large amount of heat.

  As described above in detail, in the second embodiment, the thermal area is heated so as to heat the area on the paper S based on the information specifying the area on the paper S where the fixing temperature of the toner image is lower than the predetermined temperature. The head 70 is controlled. According to the second embodiment configured as described above, a region A related to the first rotation of the fixing belt and a region related to the second rotation of the fixing belt while suppressing a significant increase in cost, an increase in the size of the apparatus, and an increase in power consumption. The temperature difference from B becomes small, and gloss unevenness (gloss level difference) can be prevented from occurring in the toner image on the paper S.

(Third embodiment)
The third embodiment is a modification of the control operation for the thermal head 70 of the control unit 80 described in the first embodiment. FIG. 4 is a diagram for explaining an example of the operation of the image forming apparatus 1 showing the third embodiment according to the present invention. In the present embodiment, the area other than the area for specifying the area on the sheet S that is positioned upstream of the thermal head 70 and is nipped and conveyed by the conveying unit (conveying roller 100) that nipping and conveying the sheet S on which the toner image is fixed. The point which controls the thermal head 70 so that an area | region is heated differs from 1st Embodiment.

  The purpose of performing the above operation is as follows. That is, the paper discharge roller 100 stores heat by continuous paper passing, and a temperature difference caused by the heat storage of the paper discharge roller 100 occurs between the region where the paper discharge roller 100 is in contact with the paper S and the region where it is not in contact. When this temperature difference is large, there arises a problem that streaky gloss unevenness (gloss level difference) occurs in the toner image on the paper S.

  As a measure for solving this problem, it is conceivable to newly install a cooling mechanism capable of preventing heat accumulation of the paper discharge roller 100. However, other problems such as an increase in equipment cost, an increase in power consumption for the cooling mechanism, and an increase in the size of the apparatus occur, which cannot be said to be an effective measure for solving the above problems.

  Therefore, in the third embodiment according to the present invention, the following configuration is adopted to prevent occurrence of uneven gloss (gloss level difference) due to heat accumulation of the paper discharge roller 100.

  In the third embodiment, the ROM 91 of the control unit 80 stores arrangement position information indicating the arrangement position of the paper discharge roller 100 in the width direction of the paper S in advance.

  As shown in FIG. 4A, the thermal drive unit 93 of the control unit 80 is held in the ROM 91 when the sheet S passes through the thermal head 70 arranged at the rear stage of the fixing device 60 in the arrow direction (conveyance direction). On the sheet S based on the position information and the sheet size included in the job information input from the operation display unit 20 (the information corresponds to “region information” in the claims). The thermal head 70 is controlled so as to heat the region A other than the region B where the roller 100 is in contact with the paper S (that is, sandwiched by the paper discharge roller 100).

  FIG. 4B is a diagram showing the relationship between the distance from one end in the width direction of the paper S and the amount of heat supplied during heating when the thermal head 70 heats the toner image fixed on the paper S. is there. As shown in FIG. 4B, the thermal driving unit 93 controls the thermal head 70 so that the paper discharge roller 100 heats the region A other than the region B in contact with the paper S with a large supply heat amount.

  As described above in detail, in the third embodiment, the region B on the sheet S that is positioned upstream of the thermal head 70 and is nipped by the conveyance roller 100 that nipping and conveying the sheet S on which the toner image is fixed. The thermal head 70 is controlled so as to heat the area A other than the area B on the paper S based on the information specifying the above. According to the third embodiment configured as described above, the region A in which the paper discharge roller 100 does not contact the region B in contact with the paper S and the increase in power consumption and increase in power consumption are suppressed. The temperature difference between the two becomes small, and streaky gloss unevenness (gloss level difference) can be prevented from occurring in the toner image on the paper S.

  In the first to third embodiments, the example in which the thermal head 70 is used as a means for heating the toner image fixed on the paper S has been described. However, the present invention is not limited to this. In short, anything may be used as long as it has a plurality of heating elements that can be controlled to heat an arbitrary area of the paper S.

  In the first to third embodiments, an example in which the thermal head 70 is disposed in the subsequent stage of the fixing device 60, that is, in the image forming apparatus 1, has been described, but the present invention is not limited to this. For example, as shown in FIG. 5, after the thermal head 70 can be connected to the image forming apparatus 1 and a predetermined post-processing (for example, binding processing using staples, folding processing, etc.) is performed on the paper S. You may make it arrange | position in front of the exit part on the paper conveyance path H0 in the processing apparatus 110. FIG. That is, the post-processing device 110 has a thermal head 70 provided to heat the paper S supplied from the image forming apparatus 1. In this case, the thermal head 70 heats the paper S on which the toner image is fixed by the fixing device 60 under the control of the control unit 80.

  As shown in FIG. 5, the post-processing device 110 includes paper transport paths H0, H1, and H2, a fixed paper discharge tray 120a, a lift paper discharge tray 120b, a post-processing unit 130, and a control unit 140. Note that a part or all of the functions of the control unit 140 may be incorporated in the control unit 80 of the image forming apparatus 1.

  The control unit 140 includes an arithmetic device such as a CPU, and controls the post-processing device 110 by executing a predetermined control program on the CPU. The control unit 140 controls the post-processing operation of the post-processing device 110 that is linked to the image forming operation of the image forming device 1 according to the job information transferred from the image forming device 1.

  The paper transport path H0 has a paper transport path having an inlet portion disposed opposite to the paper discharge section 53 of the image forming apparatus 1 in order to introduce the paper S discharged from the image forming apparatus 1 into the post-processing apparatus 110. It is. The paper transport path H0 branches to the paper transport paths H1 and H2 at the exit.

  The paper transport path H1 is a paper discharge path for transporting the paper S that is not subject to post-processing and discharging it to the fixed paper discharge tray 120a. The paper transport path H <b> 2 is a paper transport path that transports the paper S to be post-processed and supplies it to the post-processing unit 130.

  The post-processing unit 130 is configured to perform a side binding process on the paper S. More specifically, the post-processing unit 130 stacks the sheets S to form a bundle of sheets, performs a side binding process on the bundle of sheets to form a booklet, and discharges the booklet to the lifting / discharging tray 120b. To do. As shown in FIG. 5, the elevating / discharging tray 120 b is inclined upward on the downstream side in the paper transport direction, and the booklet is stacked in an inclined manner. Further, the elevating / discharging tray 120b is lowered every time a booklet is discharged, and a large number of booklets can be stacked.

  In the first to third embodiments, the image forming apparatus 1 inputs image data corresponding to a document transported from the automatic document feeder 11 onto the contact glass or a document placed on the contact glass. However, the present invention is not limited to this example. For example, the image forming apparatus 1 receives an input transmitted from an external device (for example, a personal computer) connected to a communication network such as a LAN (Local Area Network) or a WAN (Wide Area Network) via a communication unit (not shown). Image data may be received, and an image may be formed on the paper S based on the received digital image data.

  In addition, each of the first to third embodiments is merely an example of the implementation of the present invention, and the technical scope of the present invention should not be construed in a limited manner. Is. That is, the present invention can be implemented in various forms without departing from the gist or the main features thereof.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 70 Thermal head 80 Control part 110 Post-processing apparatus

Claims (9)

A heating unit for heating the toner image fixed on the paper;
A heating apparatus comprising: a control unit that controls the heating unit so as to heat an arbitrary region of the paper.   The heating apparatus according to claim 1, wherein the heating unit is a thermal head having a plurality of heating elements arranged in a width direction of the paper.   The control unit controls the heating unit to heat the region on the paper based on region information specifying a region where the fixing temperature of the toner image is lower than a predetermined temperature on the paper. Or the heating apparatus of 2.   The control unit is located upstream of the heating unit and is based on area information for specifying an area on the sheet that is nipped by a conveyance unit that nipping and conveying the sheet on which the toner image is fixed. The heating apparatus according to claim 1, wherein the heating unit is controlled to heat a region other than the region above. A post-processing apparatus that can be connected to an image forming apparatus that forms a toner image on a sheet and performs predetermined post-processing on the sheet,
The post-processing apparatus which has the said heating part of any one of Claims 1-4 provided so that the paper supplied from the said image forming apparatus may be heated. A heating unit for heating the toner image fixed on the paper;
An image forming apparatus comprising: a control unit that controls the heating unit so as to heat an arbitrary region of the sheet.   The image forming apparatus according to claim 6, wherein the heating unit is a thermal head having a plurality of heating elements arranged in a width direction of the sheet.   The control unit controls the heating unit to heat the region on the paper based on region information that specifies a region where the fixing temperature of the toner image is lower than a predetermined temperature on the paper. Or the image forming apparatus according to 7; The controller heats an area other than the area on the sheet based on area information for specifying an area on the sheet that is nipped and conveyed by a conveyance unit that nipping and conveying the sheet on which the toner image is fixed. The image forming apparatus according to claim 6, wherein the heating unit is controlled as described above.

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