JP2018017828A - Image formation apparatus - Google Patents

Abstract

Information that disappears due to heating is output, and re-entry of a document with a coloring material (writing tool) that does not easily lose color is urged. An image forming apparatus includes: an operation receiving unit; a reading unit that reads a sheet; a printing unit that includes a fixing unit that heats and fixes a toner image; an output unit that outputs information; The pre-passage image data obtained by reading the sheet and the post-passage image data obtained by the reading unit reading the sheet after passing through the fixing unit are compared, and whether there is information that has disappeared after passing through the fixing unit. And a control unit that causes the output unit to output the erased information when it is determined that there is erased information. [Selection] Figure 6

Description

  The present invention relates to an image forming apparatus including a fixing unit that heats a sheet.

  There are coloring materials that can be erased by heating. An example of a writing instrument using ink that can be erased by heating is described in Patent Document 1.

  Specifically, Patent Document 1 includes an electron-donating color-forming organic compound, an electron-accepting compound, a microcapsule pigment containing a temperature-sensitive color-changing color memory composition that controls a color reaction, a solvent, The resin contains a microcapsule pigment having a hysteresis width of 40 to 70 ° C. with respect to the color density-temperature curve, a complete decolorization temperature of 45 to 95 ° C., and a color development start temperature of 0 ° C. or less. A heat-erasable writing instrument is described which is filled with a temperature-sensitive color-changing color-memory ink composition that changes from colored to colorless. It is intended to provide a heat erasable writing instrument that can thermally erase the handwriting (ink) by rubbing, maintain the erased state of the handwriting in a normal temperature range, and repetitively write on the erased part (Patent Document 1: Claim 1, Paragraph [ 0003].

JP 2006-063238 A

  An example of a color material that can be erased by heating is friction ink. With a pen using friction ink, the color of the entry portion (ink portion in the paper) can be erased by rubbing and applying heat. The friction ink writing instrument has the advantages that it is easy to rewrite, eraser does not appear like an eraser, and disappears even if it is not rubbed with a strong force. In addition, some pens that can be erased by heating have less color residue than when erased with a eraser.

  However, since it can be erased, color materials that can be erased by heating should be applied to documents that should be kept for a long time, such as official documents, private documents submitted to companies and government offices, and documents that should not be tampered with such as experimental reports. Should not be used. For example, in a high temperature environment such as a summer document storage warehouse, information in the document may be lost. In addition, information in documents may be lost due to temperature rises in automobiles in summer. Furthermore, some writing instruments using color materials that can be erased by heating can easily lose their color without application of heat. A note may be attached to a document so that it will not be filled with a writing instrument that uses a colorant that can be erased by heating. In addition, the writing instrument manufacturer may be careful not to use it on documents that must not be erased.

  However, there are those who fill out documents with a writing instrument using a coloring material that can be erased by heating without being noticed. In order to prevent the written information from being lost or falsified, there is a problem that it should not be left as it is, but should be rewritten with a coloring material (writing tool) that does not easily lose its color. However, it is difficult to discriminate visually whether or not a color material that can be erased by heating is described.

  The writing instrument described in Patent Document 1 uses ink that can erase the color simply by rubbing. Therefore, the above problem cannot be solved. The writing instrument described in Patent Document 1 can be easily tampered with, and even if the contents of the document are confirmed at a later date, the contents may be erased.

  In view of the above problems, the present invention outputs information disappeared by heating, and prompts re-entry of a document with a color material (writing tool) that does not easily lose color.

  In order to achieve the above object, an image forming apparatus according to a first aspect includes an operation receiving unit, a reading unit, a printing unit, an output unit, a storage unit, and a control unit. The operation accepting unit accepts a user operation. The reading unit reads the sheet and generates image data. The printing unit includes a sheet feeding unit that supplies a sheet, a conveying unit that conveys the sheet, an image forming unit that forms a toner image on the sheet, a transfer unit that transfers the formed toner image to a sheet, and a transferred toner It includes a fixing unit that heats and fixes the image. The output unit outputs information. The storage unit stores pre-pass image data obtained by the reading unit reading the sheet before passing through the fixing unit and post-pass image data obtained by reading the sheet after passing through the fixing unit. Remember. The control unit compares the pre-passage image data with the post-passage image data to determine whether there is information that has disappeared after passing through the fixing unit. The output information is output to the output unit.

  According to the present invention, it is possible to determine whether there is information that has disappeared due to heating of the fixing unit. Moreover, the disappeared information can be output, and re-entry can be promoted with a writing instrument in which the color is difficult to disappear. In addition, the document is not left as it is written with a color material that can be erased by heating. Therefore, it is possible to prevent the information written on the document from being lost or falsified.

1 is a diagram illustrating an example of a multifunction machine according to an embodiment. 1 is a diagram illustrating an example of a multifunction machine according to an embodiment. 10 is a flowchart illustrating an example of a flow of registration of form data D1 to the multifunction peripheral according to the embodiment. It is a figure which shows an example of the attention area setting screen which concerns on embodiment. It is a flowchart which shows an example of the flow of acquisition of the image data before passage in the decoloring confirmation mode which concerns on embodiment. It is a flowchart which shows an example of the flow of acquisition and determination of post-passing image data in the decoloring confirmation mode according to the embodiment. It is a figure which shows an example of the output in the multifunctional device which concerns on embodiment. It is a flowchart which shows an example of the flow of acquisition of the image data before passage in the decoloring confirmation mode which concerns on embodiment. 6 is a flowchart illustrating an example of a flow of passing through a fixing unit in a decoloring confirmation mode according to an embodiment. It is a flowchart which shows an example of the flow of acquisition and determination of post-passing image data in the decoloring confirmation mode according to the embodiment. 6 is a flowchart illustrating an example of a process flow of a protection mode of the multifunction peripheral according to the embodiment.

  The image forming apparatus according to the present invention will be described below with reference to FIGS. The image forming apparatus will be described using the multifunction peripheral 100 as an example. However, each element such as configuration and arrangement described in this embodiment does not limit the scope of the invention and is merely an illustrative example.

(Outline of MFP 100)
First, the multifunction peripheral 100 according to the embodiment will be described with reference to FIGS. 1 and 2. 1 and 2 are diagrams illustrating an example of the multifunction peripheral 100 according to the embodiment.

  The multifunction device 100 includes a control unit 1 and a storage unit 2. The control unit 1 controls the overall operation of the apparatus and controls each unit of the multifunction peripheral 100. The control unit 1 includes a CPU 11, an image processing unit 12, and an OCR processing unit 13. The CPU 11 performs calculations related to control. The image processing unit 12 performs image processing necessary for the job on the image data. The OCR processing unit 13 performs OCR (Optical Character Recognition) processing of the image data, and extracts text data D5 from the image data. The storage unit 2 includes storage devices such as ROM, RAM, and HDD, and stores control programs and various data.

  The control unit 1 is connected to the image reading device 3 so as to be communicable. The image reading device 3 includes a document conveying unit 3a and an image reading unit 3b. The document transport unit 3a transports the set document toward the reading position. The image reading unit 3b reads a document conveyed by the document conveying unit 3a or a document set on a document table (contact glass), and generates image data. The control unit 1 controls the operations of the document conveying unit 3a and the image reading unit 3b.

  The operation panel 4 (corresponding to an operation reception unit) includes a display unit 41 (display panel), a touch panel 42, and hard keys 43. The control unit 1 controls display on the display unit 41. The control unit 1 causes the display unit 41 to display a setting screen. Based on the output of the touch panel 42, the control unit 1 recognizes an operated image such as a soft key displayed on the display unit 41. The control unit 1 recognizes the operated hard key 43. The control unit 1 causes the display unit 41 to switch to a screen corresponding to the operated operation image or the hard key 43. The control unit 1 recognizes the contents of the setting operation performed on the operation panel 4 and controls the multifunction peripheral 100 so as to operate as set.

  The multifunction device 100 includes a printing unit 5. The printing unit 5 includes a paper feeding unit 5a, a conveyance unit 5b, an image forming unit 5c, an intermediate transfer unit 5d (corresponding to a transfer unit), and a fixing unit 5e. The control unit 1 causes the sheet feeding unit 5a to supply sheets one by one during a print job. The multifunction machine 100 includes a first paper feed cassette 51, a second paper feed cassette 52, and a manual paper feed unit 53 as the paper feed unit 5a. The control unit 1 causes the conveyance unit 5b to convey the sheet to the discharge tray 54 through the image forming unit 5c and the fixing unit 5e. The control unit 1 causes the image forming unit 5c to form a toner image on the sheet conveyed from the conveyance unit 5b.

  The image forming unit 5c is a unit that forms a toner image using toner, in order from the left in FIG. 2, an image forming unit 6Bk that forms a black toner image, an image forming unit 6Y that forms a yellow toner image, and cyan. An image forming unit 6C for forming a toner image, an image forming unit 6M for forming a magenta toner image, and a protective layer forming unit 6 for forming a transparent toner image using a transparent toner.

  The control unit 1 causes the intermediate transfer unit 5d to perform primary transfer of the toner image formed by the image forming unit 5c to the intermediate transfer belt 55, and performs intermediate transfer of the toner image on the intermediate transfer belt 55 to the sheet. The transfer unit 5d performs the process. The controller 1 heats and presses the sheet, and causes the fixing unit 5e to fix the toner image transferred to the sheet. The fixing unit 5 e includes a heating roller 57 that includes a heater 56 and heats the sheet, and a pressure roller 58 that presses against the heating roller 57. The conveyance unit 5 b discharges the printed sheet to the discharge tray 54. The multi-function device 100 is provided with a plurality of motors 5f that rotate various rotating bodies that rotate in contact with the sheet (only one motor 5f is shown in FIG. 1 for convenience).

  The multifunction device 100 (control unit 1) includes a communication unit 14. The communication unit 14 is an interface for communicating with a computer 200 such as a PC or a server. The communication unit 14 receives job data including data indicating print contents such as image data and data indicating settings related to printing from the computer 200. The control unit 1 causes the printing unit 5 to perform printing based on the job data.

  The multifunction device 100 also includes a sheet reading unit 7 for reading the conveyed sheet. The sheet reading unit 7 is provided in a conveyance path (conveyance unit 5b) from the manual sheet feeding unit 53 to the intermediate transfer unit 5d (secondary transfer roller 511). The sheet reading unit 7 can read the entire sheet of the maximum size that can be set. For example, the sheet reading unit 7 is a CIS scan unit. The sheet reading unit 7 processes and digitizes a lamp that irradiates light on the sheet, an image sensor (line sensor), a lens that guides the light reflected by the sheet to the image sensor, and the charge output from each light receiving element of the image sensor. A circuit for generating image data.

(Registration of form data D1)
Next, an example of the flow of registration of the form data D1 to the multifunction peripheral 100 according to the embodiment will be described with reference to FIGS. FIG. 3 is a flowchart illustrating an example of the registration flow of the form data D1 to the multifunction peripheral 100 according to the embodiment. FIG. 4 is a diagram illustrating an example of the attention area setting screen S1 according to the embodiment.

  The multifunction device 100 has a decoloring confirmation mode for confirming and determining a portion written with a color material that can be erased by heating. Then, it is possible to register a document form targeted for the decoloration confirmation mode. Here, the form is a form, model, or form of a document in which an area to be filled in is determined, such as a name field and an address field. Hereinafter, an example of a registration flow of image data (form data D1) indicating a form will be described. The start of the flowchart of FIG. 3 is when the control unit 1 recognizes a form registration instruction on the operation panel 4.

  First, the multi-function device 100 accepts input of form data D1 (step # 11). The form data D1 is image data indicating a document or document form to be registered (protected). Specifically, the image reading unit 3b is used as a form receiving unit. The image reading unit 3b reads a document that is set and contains a form to be registered, and generates image data. In this manner, the image reading unit 3b accepts input of image data of the form of the sheet to be protected. The form data D1 may be registered by transmitting form image data to be registered from the computer 200 to the communication unit 14. In this case, the communication unit 14 functions as a form reception unit.

  The control unit 1 stores the image data generated by the image reading unit 3b or the image data received by the communication unit 14 in the storage unit 2 as form data D1 (step # 12). Forms may require you to enter certain types of information at specific locations, such as name and address fields. By comparing only specific entry areas, it is possible to easily determine whether or not information is written with a color material that can be erased by heating. Therefore, when registering a form, a region of interest (region of interest) may be set in the determination of the decoloring confirmation mode.

  FIG. 4 is a diagram illustrating an example of the attention area setting screen S1 according to the embodiment. The control unit 1 causes the display unit 41 to display a region setting image i1 based on the image data (form data D1) obtained by reading by the image reading device 3. FIG. 4 shows an example in which an area setting image i1 of a sheet of an application form is displayed in the attention area setting screen S1.

  By flicking the touch panel 42 or operating the scroll bar i2 arranged on the right side of the screen, it is possible to move the displayed portion of the region setting image i1 (form data D1). Further, the magnification of the displayed area setting image i1 can be enlarged or reduced by a pinch-in / pinch-out operation. The attention area setting screen S1 is provided with a first setting key K1 and a second setting key K2 for setting the attention area of the sheet.

  When the first setting key K1 is operated, the control unit 1 recognizes the area surrounded by tracing (moving the fingertip while touching) as the attention area. When the second setting key K2 is operated, the control unit 1 recognizes the area including the touch point as the attention area. Here, the control unit 1 recognizes an area surrounded by a ruled line in the form data D1 (area setting image i1) as a column. For example, the control unit 1 recognizes a straight line having a certain density or more as a ruled line in the form data D1 (image data), and recognizes an area closed by a plurality of (four) ruled lines as a column. Thus, the previous operation panel 4 accepts an operation for setting a region of interest. FIG. 4 shows an example of a state in which the blank on the right side of the column in which the character of the name is written is touched in order to set the name entry column as the attention area. Then, the control unit 1 causes the storage unit 2 to store position data D2 indicating the position of the region of interest set by specifying the tracing or column in the form data D1 in association with the form data D1 (step # 14). . Then, this flow ends.

  When the attention area can be set, when the information on the attention area of the pre-passage image data D3 disappears in the post-passage image data D4, the control unit 1 determines that there is information disappeared after passing through the fixing unit 5e. To do. Even if the form is not registered in advance, one sheet is read in advance by the image reading device 3 at the start of the decoloring confirmation mode, and the attention area is set on the operation panel 4 based on the image data obtained by the reading. You may be able to do it.

(Processing in the decoloring confirmation mode using the sheet reading unit 7)
Next, an example of the flow of processing in the decoloring confirmation mode using the sheet reading unit 7 will be described with reference to FIGS. FIG. 5 is a flowchart illustrating an example of a flow of obtaining the pre-passage image data D3 in the decoloring confirmation mode according to the embodiment. FIG. 6 is a flowchart showing an example of the flow of acquisition and determination of post-passing image data D4 in the decoloration confirmation mode according to the embodiment. FIG. 7 is a diagram illustrating an example of output from the multifunction peripheral 100 according to the embodiment.

  The multifunction peripheral 100 according to the embodiment includes a sheet reading unit 7. In the decoloring confirmation mode, the following flow is performed. (1) The control unit 1 obtains image data (pre-passage image data D3) of a sheet before passing through the fixing unit 5e (pre-passage sheet). (2) The control unit 1 passes the fixing unit 5e and heats the sheet. (3) The control unit 1 obtains image data (post-passage image data D4) of the heated sheet (post-passage sheet). (4) The control unit 1 compares the pre-passage image data D3 and the post-passage image data D4, determines whether there is information that has disappeared after passing through the fixing unit 5e, and outputs the determination result. As a result of executing the decoloring confirmation mode, it is possible to specify a document written with a color material that can be erased by heating. Then, the document should be written only with color materials that do not easily lose color.

  The start of the flowchart of FIG. 5 is the time point when the control unit 1 recognizes the input of the execution instruction for the process of the decoloring confirmation mode using the sheet reading unit 7. The user performs a predetermined operation on the operation panel 4 and inputs this execution instruction to the multi-function device 100 (operation panel 4).

  The control unit 1 starts energizing the heater 56 of the fixing unit 5e, raises the temperature of the fixing unit 5e (heating roller 57) to the decoloring temperature, and maintains it at the decoloring temperature (step # 21). The decoloring temperature may be the same as the temperature at the time of fixing the toner image (a temperature of about several hundred to two hundred degrees, a fixing control temperature). Further, a temperature of about 100 degrees is sufficient for erasing the friction ink. Therefore, the decoloring temperature may be lower than the fixing control temperature.

  A sheet before passing (a sheet for checking whether information is written with a color material that can be erased by heating) is set by the user (step # 22). The pre-passage sheet is set in the manual sheet feeding unit 53 so that the sheet reading unit 7 can read the sheet. A plurality of pre-passage sheets may be set. The manual sheet feeder 53 is provided with a set sensor 510 (see FIG. 2) that detects the presence or absence of a sheet. The control unit 1 checks the presence or absence of a pre-passing sheet set in the manual sheet feeding unit 53 based on the output of the set sensor 510. Note that the pre-passage sheet may be set in a paper feed cassette. In this case, the sheet reading unit 7 is provided at a position where the sheet can be read.

  When a sheet is set in the manual sheet feeding unit 53, the control unit 1 starts feeding the first sheet of the set pre-passage sheets and continues the conveying operation (step #). 23). Specifically, the control unit 1 starts rotation of a rotating body (rotating body of the manual sheet feeding unit 53, the conveying unit 5b, the image forming unit 5c, the intermediate transfer unit 5d, and the fixing unit 5e) related to sheet feeding and sheet conveyance. . The control unit 1 causes the sheet reading unit 7 to read the pre-passage sheet being conveyed (step # 24). The control unit 1 stores the image data obtained by reading in the storage unit 2 as pre-passage image data D3 (step # 25).

  The controller 1 recognizes the form data D1 corresponding to the set sheet (sheet bundle) based on the obtained pre-passage image data D3 (step # 26). For example, the OCR processing unit 13 of the control unit 1 recognizes characters, numbers, and symbols included in the pre-passage image data D3, and corresponds to a sheet in which the form data D1 that includes the same most characters, numbers, and symbols is set. May be recognized as form data D1. Further, the control unit 1 recognizes the number of ruled lines and the number of columns included in the image data, and recognizes the form data D1 matching these numbers as the form data D1 corresponding to the set sheet. Also good.

  Then, the control unit 1 continues the conveyance of the pre-passage sheet and passes the fixing unit 5e (step # 27). At this time, information written with a color material that can be erased by heating disappears. Further, the control unit 1 rotates the rotating member related to sheet conveyance such as the intermediate transfer belt 55 for the image forming unit 5c and the intermediate transfer unit 5d, but does not perform toner image formation or transfer. Further, the control unit 1 discharges the sheet to the conveyance unit 5b and the fixing unit 5e toward the discharge tray 54 (step # 28).

  Based on the output of the set sensor 510, the controller 1 checks whether or not the pre-passage sheet remains in the manual sheet feeder 53 (step # 29). When remaining (Yes in Step # 29), the control unit 1 starts feeding the next pre-passage sheet (Step # 210). Note that the control unit 1 can feed one sheet after the feeding from the manual sheet feeding unit 53 is started so that the sheet interval of the set sheets becomes a certain amount or more and sheets are not continuously fed. When a certain time has elapsed, the paper feeding operation of the manual paper feeding unit 53 is stopped. Then, the flow returns to step # 24. In the second and subsequent sheets, step # 26 is skipped.

  When not remaining (No in Step # 29), the control unit 1 stops the motor 5f and stops the sheet conveyance (Step # 211). Specifically, the control unit 1 stops the rotating body related to sheet conveyance of the manual sheet feeding unit 53, the conveyance unit 5b, the image forming unit 5c, the intermediate transfer unit 5d, and the fixing unit 5e. Further, the control unit 1 turns off the heater 56 of the fixing unit 5e.

  Next, an example of the flow of obtaining post-passage image data D4 and determining whether there is information that has disappeared will be described with reference to FIG. The start of FIG. 6 is when all of the sheets (passed sheets) that have passed through the fixing unit 5 e and discharged to the discharge tray 54 are reset in the manual sheet feeding unit 53. This resetting is performed by the user. When there are a plurality of sheets, the order of the sheets before passing and the sheets after passing (page order) is the same. Thereby, the order in which the pre-passage image data D3 is generated and the order in which the post-passage image data D4 is generated are the same. By comparing the pre-passage image data D3 and the post-passage image data D4 that are generated in the same order, the pre-passage image data D3 and the post-passage image data D4 of the same sheet can be compared.

  When the post-passage sheet is reset in the manual paper feed unit 53, the control unit 1 starts feeding the first first of the reset post-passage sheets and continues the transport operation (step) # 31). The control unit 1 causes the sheet reading unit 7 to read the conveyed post-passage sheet (step # 32). The control unit 1 stores the image data obtained by reading in the storage unit 2 as post-passage image data D4 (step # 33).

  The controller 1 compares the pre-passing image data D3 corresponding to the sheet being conveyed with the post-passing image data D4 (step # 34). Then, the control unit 1 determines whether or not there is information that disappears after passing through the fixing unit 5e (information written with a color material that can be erased by heating) in the post-passing sheet that is being conveyed (step # 35). ). When the information described in the attention area of the pre-passage image data D3 disappears in the attention area of the post-passage image data D4, the control unit 1 determines that there is information that has disappeared after passing through the fixing unit 5e. The control unit 1 recognizes the position of the attention area based on the position data D2 of the form data D1.

  For example, in the same sheet, the control unit 1 (OCR processing unit 13) performs OCR processing on each of the attention area of the pre-passage image data D3 and the attention area of the post-passage image data D4. The control unit 1 compares the text data D5 obtained by the OCR process for the pre-passage image data D3 and the text data D5 obtained by the OCR process for the post-passage image data D4 for the same sheet. The control unit 1 determines that the information on the attention area has disappeared when the number of texts extracted before and after passing through the fixing unit 5e on the same sheet is smaller by a predetermined number or when there is no text after passing.

  Further, the control unit 1 may determine whether or not the information has disappeared based on the pixel values of the pixels included in the attention area. The pixel value where the character color such as black disappears corresponds to the background color of the sheet such as white and changes to a bright value. Therefore, the control unit 1 has a darker (darker) number of pixels than the reference pixel value in the attention area of the post-passage image data D4 than the reference pixel value in the attention area of the pre-passage image data D3. When the number of pixels is less than the threshold value, it may be determined that the information on the attention area has disappeared.

  The control unit 1 continues to convey the sheet after passing, and passes the fixing unit 5e (step # 36). For a post-passage sheet that has no disappeared information, the control unit 1 rotates a rotating body related to sheet conveyance, such as the intermediate transfer belt 55, but does not perform toner image formation or transfer. On the other hand, when the sheet having the disappeared information is passed for the second time, the control unit 1 causes the image forming unit 5c to form a toner image of the identification mark indicating that the disappeared information is present. The toner image of the identification mark may be transferred to the transfer unit on the sheet, and the fixing unit 5e may fix the toner image of the identification mark. For example, a small circle is added as an identification mark at the rear end of the sheet. The control unit 1 discharges the passed sheet toward the discharge tray 54 to the conveyance unit 5b and the fixing unit 5e (step # 37).

  Based on the output of the set sensor 510, the controller 1 checks whether or not the post-passage sheet remains in the manual sheet feeder 53 (step # 38). When remaining (Yes in Step # 38), the control unit 1 starts feeding and transporting the next post-passage sheet (Step # 39). This is the same as step # 210 in FIG. The flow returns to step # 32. When it does not remain (No in Step # 38), the control unit 1 stops the motor 5f and stops the conveyance of the sheet after passing (similar to Step # 310 and Step # 211). The acquisition of the pre-passage image data D3 and the post-passage image data D4 of all the set sheets is completed according to the flowcharts of FIGS.

  Then, the control unit 1 confirms whether any information has disappeared after passing through the fixing unit 5e in any sheet (step # 311). If the information is not erased in any sheet (No in step # 311), the user does not need to be notified, and the flow ends (end). When there is a sheet in which information has disappeared (step # 311), the control unit 1 causes the output unit to output the disappeared information (step # 312 → end). Here, the output unit may be the printing unit 5 or the display unit 41. In the case of the printing unit 5, the disappeared information is printed out. In the case of the display unit 41, the disappeared information is displayed and output. FIG. 7 shows an example when the disappeared information is printed out.

  As shown in FIG. 7, the control unit 1 outputs the number of pages of the sheet from which the information has disappeared. The information that disappeared on the page is also output. FIG. 7 shows an example of output when information is erased on the second sheet and the tenth sheet among sheets set in the manual sheet feeder 53. Further, FIG. 7 shows an example in which the information disappeared by passing through the fixing unit 5e is a name and an address. As shown in FIG. 7, the control unit 1 performs an OCR process on the attention area in the pre-passage image data D3, stores the text obtained by the OCR process in the storage unit 2, and disappears after passing through the fixing unit 5e. Text corresponding to the information may be output to the output unit. Further, the control unit 1 may output the image data of the area (attention area) where the disappeared information is described in the pre-passage image data D3 instead of the text data D5.

(Processing in the decoloring confirmation mode using the image reading device 3)
Next, an example of the flow of processing in the decoloring confirmation mode using the image reading device 3 will be described with reference to FIGS. FIG. 8 is a flowchart illustrating an example of a flow of acquiring pre-passage image data D3 in the decoloration confirmation mode according to the embodiment. FIG. 9 is a flowchart illustrating an example of a flow of passage through the fixing unit 5e in the decoloring confirmation mode according to the embodiment. FIG. 10 is a flowchart showing an example of the flow of obtaining and determining post-passing image data D4 in the decoloration confirmation mode according to the embodiment.

  The multifunction device 100 includes an image reading device 3. Therefore, it is possible to acquire the pre-passage image data D3 and the post-passage image data D4 using the image reading device 3. When the image reading device 3 is used, the number of times of setting a sheet is increased as compared with the case where the sheet reading unit 7 is used, but the sheet reading unit 7 is not required. For this reason, the sheet reading unit 7 may not be provided in the multifunction peripheral 100, and the process of the decoloring confirmation mode may be performed using the image reading device 3. Further, when both the sheet reading unit 7 and the image reading device 3 are provided in the multifunction peripheral 100, it may be possible to select which one to use on the operation panel 4. In the following description, an example of obtaining pre-passage image data D3 and post-passage image data D4 using the image reading device 3 will be described.

  The start of the flowchart of FIG. 8 is the time point when the control unit 1 recognizes the execution instruction for the process of the color erasure confirmation mode using the image reading device 3. The user performs a predetermined operation on the operation panel 4 and inputs this execution instruction to the multi-function device 100 (operation panel 4). The user sets a pre-passage sheet (a bundle of pre-passage sheets) on the image reading device 3 (original transport unit 3a) (step # 41). The document transport unit 3a is provided with a document set sensor 31 (see FIG. 2) that detects the presence or absence of a sheet. Based on the output of the document set sensor 31, the control unit 1 checks whether or not a sheet is set on the document transport unit 3a (the presence or absence of a sheet).

  When a sheet is set on the document conveying unit 3a, the control unit 1 starts feeding and conveying the first pre-passage sheet among the set pre-passage sheets (step # 42). The control unit 1 causes the image reading device 37 (image reading unit 3b) to read the pre-passage sheet being conveyed (step # 43). The control unit 1 stores the image data obtained by reading in the storage unit 2 as pre-passage image data D3 (step # 44).

  The controller 1 recognizes the form data D1 corresponding to the set pre-passage sheet (sheet bundle) based on the obtained pre-passage image data D3 (step # 45). Since this process is the same as step # 26, description thereof is omitted. The control unit 1 continues the conveyance of the pre-passage sheet and discharges the sheet from the document conveyance unit 3a (step # 46). Based on the output of the document set sensor 31, the control unit 1 checks whether or not the pre-passage sheet remains in the document transport unit 3a (step # 47). When remaining (Yes in Step # 47), the control unit 1 starts feeding the next pre-passage sheet (Step # 48). Then, the flow returns to step # 43. In the second and subsequent sheets, step # 45 is skipped. When it does not remain (No in step # 47), this flow ends (end).

  Next, an example of the flow of the passing process of the sheet (sheet bundle) fixing unit 5e will be described with reference to FIG. The start of FIG. 9 is the time when the document conveyance unit 3a completes sheet conveyance and pre-passage image data D3 acquisition. First, the control unit 1 starts energizing the heater 56 of the fixing unit 5e, raises the temperature of the fixing unit 5e (heating roller 57) to the decoloring temperature, and maintains it at the decoloring temperature (step # 51). The decoloring temperature is the same as in step # 21.

  Then, the sheet on which the post-passage image data D4 has been acquired (acquired sheet) is set by the user (step # 52). The acquired sheet may be set in the manual sheet feeding unit 53 or in another sheet feeding cassette. The control unit 1 starts feeding the first one of the acquired sheets that have been set, and continues the conveying operation (step # 53). Specifically, the control unit 1 starts to rotate the rotating body (the rotating body of the sheet feeding unit 5a, the conveying unit 5b, the image forming unit 5c, the intermediate transfer unit 5d, and the fixing unit 5e) related to sheet feeding and sheet conveyance.

  Then, the control unit 1 continues the acquired sheet conveyance and passes the fixing unit 5e (step # 54). For the image forming unit 5c and the intermediate transfer unit 5d, the control unit 1 rotates the rotating body related to sheet conveyance such as the intermediate transfer belt 55, but does not perform toner image formation or transfer. Further, the control unit 1 discharges the sheet to the conveyance unit 5b and the fixing unit 5e toward the discharge tray 54 (step # 55).

  Based on the output from the set sensor 510, the control unit 1 checks whether or not the acquired sheet remains (step # 56). When remaining (Yes in Step # 56), the control unit 1 starts feeding the next acquired sheet (Step # 57). This is the same as step # 210. When not remaining (No in Step # 56), the control unit 1 stops the motor 5f and stops the sheet conveyance (Step # 58). Further, the control unit 1 turns off the heater 56 of the fixing unit 5e.

  Next, an example of the flow of acquisition and determination of post-passage image data D4 in the decoloration confirmation mode will be described with reference to FIG. The start of FIG. 10 is a point in time when all sheets (sheets after passing) that have passed through the fixing unit 5e and discharged to the discharge tray 54 have been reset by the user to the image reading device 3 (original transport unit 3a). . When there are a plurality of sheets, the order of the pages of the pre-passage sheet and the post-passage sheet is the same.

  A sheet that passes through the fixing unit 5e (a sheet for confirming whether or not information is written with a color material that can be erased by heating) is reset by the user in the image reading device 3 (original conveying unit 3a). (Step # 61). Based on the output of the document setting sensor 31, the control unit 1 checks whether or not a sheet has been set in the document conveying unit 3a (the presence or absence of a sheet).

  When a sheet is set in the document conveying section 3a, the control section 1 starts feeding and conveying the first sheet among the reset sheets after passing (step # 62). The control unit 1 causes the image reading device 37 (image reading unit 3b) to read the conveyed post-passage sheet (step # 63). The control unit 1 stores the image data obtained by reading in the storage unit 2 as post-passage image data D4 (step # 64).

  The controller 1 compares the pre-passing image data D3 and post-passing image data D4 of the sheet being conveyed (step # 65). Then, the control unit 1 determines whether there is information that disappears after passing through the fixing unit 5e (information written with a color material that can be erased by heating) in the sheet being conveyed (step # 66). Steps # 65 and # 66 are the same as steps # 34 and # 35. Thereafter, the control unit 1 discharges the post-passage sheet from the conveyance path in the document conveyance unit 3a (step # 67).

  Based on the output of the document setting sensor 31, the control unit 1 checks whether or not the post-passage sheet set on the document conveying unit 3a remains (step # 68). When remaining (Yes in Step # 68), the control unit 1 starts feeding and transporting the next post-passage sheet (Step # 69). This is the same as step # 39. Then, the flow returns to step # 63.

  When not remaining (No in Step # 68), the controller 1 stops the motor 5f and stops the sheet conveyance (similar to Step # 610 and Step # 310). Then, the control unit 1 confirms whether any information has disappeared after passing through the fixing unit 5e in any sheet (step # 611). If the information is not erased in any sheet (No in step # 611), there is no content to be notified to the user, and the flow ends (END). When there is a sheet in which information has disappeared (Yes in Step # 611), the control unit 1 causes the output unit to output the disappeared information (Step # 612 → End). Step # 612 may be the same as step # 312, and the description can be used (see FIG. 7).

(Protection mode)
Next, an example of protection mode processing installed in the multifunction peripheral 100 according to the embodiment will be described with reference to FIG. FIG. 11 is a flowchart illustrating an example of a protection mode process flow of the multifunction peripheral 100 according to the embodiment.

  The multifunction device 100 includes a protective layer forming unit 6. The multifunction peripheral 100 has a print mode in which a transparent toner image is placed on a specific area (protection area) to be protected on the sheet, and information described in the protection area is protected. In the following description, this mode is referred to as a protection mode. Regarding printing in the protection mode, the operation panel 4 receives an operation for setting a protection area of the sheet. In the protection mode, form data D1 which is image data of a document form (format, template, format, format) and a protection area of the form are set in advance, and data (protection area data) indicating the position of the protection area is set. Register in the storage unit 2 in advance. The attention area set when registering the form data D1 shown in FIGS. 3 and 4 may be treated as a protection area. Further, a protection area may be set separately from the attention area when registering the form data D1.

  By setting a sheet including the registered form and starting printing in the protection mode, the set protection area is covered with the transparent toner image. As a result, the contents of the protection area are protected by the transparent toner image. Hereinafter, an example of the flow of printing a transparent toner image in the protection mode will be described with reference to the flowchart of FIG.

  The start of the flowchart of FIG. 11 is when the control unit 1 recognizes that an instruction to execute printing in the protection mode has been input to the operation panel 4. Before starting, the user sets a sheet (sheet bundle) to be protected with the transparent toner in the manual sheet feeding unit 53. The control unit 1 causes the text data D5 and the conveyance unit 5b to start feeding and conveying one set sheet (step # 71). Subsequently, the control unit 1 causes the sheet reading unit 7 to read the conveyed sheet (step # 72).

  Based on the image data obtained by reading by the sheet reading unit 7, the control unit 1 forms data D <b> 1 corresponding to a sheet set in the manual sheet feeding unit 53 among the form data D <b> 1 stored in the storage unit 2. Is recognized (step # 73). The control unit 1 recognizes the form data D1 corresponding to the sheet set in the manual sheet feeding unit 53 by comparing the image data obtained by the reading of the sheet reading unit 7 with each form data D1. When the sheet reading unit 7 is not provided, the user selects the form data D1 in advance using the operation panel 4. Based on the operation on the operation panel 4, the control unit 1 may recognize the form data D 1 corresponding to the sheet set in the manual sheet feeding unit 53.

  For example, the control unit 1 (OCR processing unit 13) recognizes characters, numbers, and symbols included in the image data, and forms corresponding to sheets on which form data D1 including the same characters, numbers, and symbols is set most. It may be recognized as data D1. Further, the control unit 1 recognizes the number of ruled lines and the number of columns included in the image data, and recognizes the form data D1 matching these numbers as the form data D1 corresponding to the set sheet. Also good. Note that the control unit 1 may recognize the form data D1 corresponding to the set sheet when reading about half or 1/4 of the set sheet in the sheet conveyance direction.

  Based on the protection area data set in accordance with the form data D1 and stored in the storage section 2, the control section 1 recognizes the position of the protection area of the set sheet (step # 74). Then, the control unit 1 causes the image forming unit 5c to form a transparent toner image to be placed on the protection area (step # 75). As a result, the area designated as the protection area and the area surrounded by the tracing are covered with the transparent toner image.

  Here, the control unit 1 causes the image forming unit 5c to form a transparent toner image so as to overlap the protection region in the sheet. A sheet sensor 513 is provided between the pair of registration rollers 512 provided in front of the secondary transfer roller 511 of the intermediate transfer unit 5d from the manual sheet feeding unit 53 (see FIG. 2). The control unit 1 recognizes the arrival of the leading edge of the sheet at the installation position of the sheet sensor 513 based on the output of the sheet sensor 513. The control unit 1 starts the formation of the transparent toner image in the image forming unit 5c (the protective layer forming unit 6 and the exposure device 59) after a predetermined time has elapsed after detecting the arrival of the leading edge of the sheet at the installation position of the sheet sensor 513. Let

  The control unit 1 conveys the sheet and causes the sheet to reach the registration roller pair 512 (see FIG. 2). A registration sensor 514 is provided in the vicinity of the upstream side of the registration roller pair 512 in the sheet conveyance direction (see FIG. 2). The controller 1 recognizes the arrival of the leading edge of the sheet at the registration roller pair 512 based on the output of the registration sensor 514. The controller 1 stops the registration roller pair 512 when the sheet arrives, and rotates the registration roller pair 512 at a timing at which the transparent toner image is appropriately secondarily transferred to the protection area. As a result, the transparent toner image is transferred to the sheet without deviation.

  The control unit 1 causes the intermediate transfer unit 5d to transfer the transparent toner image to the protection area or the like on the sheet, and fixes the transparent toner image to the fixing unit 5e (step # 76). As a result, the sheet is discharged out of the apparatus (discharge tray 54) (step # 77). The control unit 1 checks whether or not a sheet remains in the manual sheet feeding unit 53 (step # 78). That is, it is confirmed whether or not the protective printing on all sheets is completed. The manual sheet feeder 53 is provided with a set sensor 510 (see FIG. 2) that detects the presence or absence of a sheet. The control unit 1 checks the presence or absence of a sheet in the manual sheet feeding unit 53 based on the output of the set sensor 510.

  When the sheet remains in the manual sheet feeder 53 (Yes in step # 78), the control unit 1 causes the manual sheet feeder 53 and the conveyance unit 5b to start feeding and conveying the next sheet (see FIG. Step # 79). Then, the flow returns to step # 75. On the other hand, when no sheet remains in the manual sheet feeder 53 (No in step # 78), this flow ends (end). As a result, the operations of the manual paper feed unit 53, the conveyance unit 5b, the image forming unit 5c, the intermediate transfer unit 5d, and the fixing unit 5e are all stopped.

  As described above, the image forming apparatus (multifunction peripheral 100) according to the embodiment includes the operation receiving unit (operation panel 4), the reading unit (sheet reading unit 7, image reading device 3), and the printing unit 5 as the image forming apparatus. , An output unit (printing unit 5, display unit 41), storage unit 2, and control unit 1. The operation reception unit receives a user operation. The reading unit reads the sheet and generates image data. The printing unit 5 includes a sheet feeding unit 5a that supplies a sheet, a conveying unit 5b that conveys the sheet, an image forming unit 5c that forms a toner image on the sheet, a transfer unit that transfers the formed toner image to a sheet, a transfer unit A fixing unit 5e for fixing the toner image by heating is included. The output unit outputs information. The storage unit 2 includes the pre-passage image data D3 obtained by reading the sheet before passing through the fixing unit 5e and the fixing unit 5e (without toner image formation or transfer). The post-passage image data D4 obtained by reading the sheet by the reading unit is stored. The control unit 1 compares the pre-passage image data D3 and the post-passage image data D4 to determine whether there is information that has disappeared after passing through the fixing unit 5e. The output information is output to the output unit.

  Thus, the sheet can be heated by passing through the fixing unit 5e. And the information described with the color material which can erase a color by heating can be erased. The image data of the sheet before heating by the fixing unit 5e (image data D3 before passing) and the image data of the sheet after heating (image data D4 after passing) are compared, and the presence / absence of information whose color has disappeared by heating is determined. be able to. Moreover, the information which disappeared by heating can be shown to the user by outputting from the output unit. You can check the information that disappeared, so you can see who's document was written with a writing instrument that uses a color material that can be erased by heating. It is possible to prompt re-entry with a color material (writing tool) that does not easily lose its color, such as oil-based ink (ballpoint pen). Therefore, it is possible to prevent the information written on the document from being lost or falsified. In addition, it is possible to prevent documents from being stored in a state written with a color material that can be erased by heating.

  The operation accepting unit accepts an operation for setting a region of interest in the pre-passage image data D3 and the post-passage image data D4. When the information on the attention area of the pre-passage image data D3 disappears in the attention area of the post-passage image data D4, the control unit 1 determines that there is information disappeared after passing through the fixing unit 5e, and the pre-passage image data D3. The information of the attention area is output to the output unit. Thereby, it can be determined whether or not the information of the attention area is described in the color material that can be erased by heating in the image data of the sheet. If a name entry area and an address entry area are set as comparison areas, it is possible to easily identify a person who fills in a color material that can be erased by heating.

  Further, the control unit 1 performs OCR processing of the pre-passage image data D3, stores the text obtained by the OCR processing in the storage unit 2, and outputs text corresponding to information disappeared after passing through the fixing unit 5e to the output unit. Output. Thereby, based on the output text, it is possible to confirm the content of the information that has disappeared and the name of the person who entered the color material that can be erased by heating.

  The image forming apparatus includes a sheet reading unit 7 that is provided in a conveyance path from the sheet feeding unit 5a to the transfer unit and reads a conveyed sheet as a reading unit. The control unit 1 feeds the sheet set in the sheet feeding unit 5a, causes the conveyance unit 5b to convey the sheet, causes the sheet reading unit 7 to read the sheet being conveyed, and controls the sheet reading unit 7 The image data obtained by reading is stored in the storage unit 2 as pre-passage image data D3, and is a sheet discharged after passing through the fixing unit 5e after being read by the sheet reading unit 7 and being a reset sheet. After passing the sheet obtained by reading the sheet reading unit 7, the sheet is fed, the sheet is conveyed to the conveying unit 5 b, the sheet reading unit 7 is re-read the sheet after the sheet is being conveyed. The image data of the sheet is stored in the storage unit 2 as post-passage image data D4. As a result, the information written with the color material that can be erased by heating can be erased and the information erased by heating of the fixing unit 5e can be confirmed simply by conveying the sheet twice in the image forming apparatus.

  Further, the control unit 1 causes the image forming unit 5c to form an identification mark toner image indicating that there is erased information, and causes the transfer unit to transfer the identification mark toner image to the sheet after passing the erased information. The toner image of the identification mark is fixed to the fixing unit 5e. Thereby, an identification mark can be attached to a sheet from which information has disappeared due to heating of the fixing unit 5e. Therefore, it is possible to easily find a sheet from which information has disappeared by heating from the sheet bundle.

  The image forming apparatus includes an image reading device 3 that reads a set original as a reading unit. The control unit 1 reads the sheet set on the image reading device 3, stores the image data obtained by the reading of the image reading device 3 in the storage unit 2 as the pre-passage image data D3, and the pre-passage image data The sheet acquisition unit 5a feeds the acquired sheet, which is the sheet for which D3 has been acquired, conveys the acquired sheet to the conveyance unit 5b, passes the acquired sheet through the fixing unit 5e, and acquires the acquired sheet. The post-passage sheet, which is a sheet that has passed through the fixing unit 5e once, is read by the image reading device 3, and the image data obtained by reading the post-passage sheet is stored as post-passage image data D4. Store in part 2. As a result, the information written in the color material that can be erased by heating is erased by the sheet conveyance once in the image forming apparatus and the reading twice by the image reading apparatus 3, and the information disappeared by the heating of the fixing unit 5e. Can be confirmed. Further, it is not necessary to provide a reading unit (sheet reading unit 7) in the sheet conveyance path.

  The output unit is one or both of the printing unit 5 and the display unit 41 that displays information. As a result, it is possible to check the information that has disappeared due to the heating of the fixing unit 5e by looking at the printed matter or the display unit 41.

  The image forming unit 5c includes a protective layer forming unit 6 that forms a transparent toner image for protecting the surface of the sheet using transparent toner. The operation reception unit receives an operation for setting a protection area in the sheet. The control unit 1 feeds the sheet set in the paper feeding unit 5a, transports the sheet to the transport unit 5b, and forms a transparent toner image to be placed on the set protection area on the image forming unit 5c. The transfer of the toner image to the protection area is performed by the transfer unit, and the transparent toner image is fixed to the fixing unit 5e. Thereby, information can be covered with the protective layer of a transparent toner image. Information of a type that is hard to lose color is written, and the written information can be protected with a transparent toner image, and loss of information contained in the sheet can be prevented over a long period of time.

  The embodiment of the present invention has been described above, but the scope of the present invention is not limited to this, and various modifications can be made without departing from the spirit of the invention. For example, in the MFP 100 according to the above-described embodiment, the example in which it is confirmed whether the information on the attention area has disappeared has been described. However, the entire pre-passage image data D3 and the post-passage image data D4 may be compared to check whether the information has disappeared by using the entire image data as a comparison range.

  The present invention can be used in an image forming apparatus including a fixing unit that heats a sheet.

DESCRIPTION OF SYMBOLS 100 MFP (image forming apparatus) 1 Control part 2 Memory | storage part 3 Image reading apparatus (reading part)
4 Operation panel (operation reception part) 41 Display part (output part)
DESCRIPTION OF SYMBOLS 5 Print part (output part) 5a Paper feed part 5b Conveyance part 5c Image formation part 5d Intermediate transfer part (transfer part) 5e Fixing part 53 Manual paper feed part 6 Protective layer formation unit 7 Sheet reading part (reading part) D3 Before passing Image data after passing through image data D4

Claims (8)

An operation accepting unit for accepting a user's operation;
A reading unit that reads the sheet and generates image data;
A sheet feeding unit that feeds the sheet, a transport unit that transports the sheet, an image forming unit that forms a toner image on the sheet, a transfer unit that transfers the formed toner image to the sheet, and heats the transferred toner image A printing unit including a fixing unit for fixing;
An output unit for outputting information;
A storage unit for storing pre-passage image data obtained by reading the sheet before passing through the fixing unit, and post-passage image data obtained by reading the sheet after passing through the fixing unit by the reading unit; ,
The pre-passage image data and the post-passage image data are compared to determine whether there is any information that has disappeared after passing through the fixing unit. An image forming apparatus comprising: a control unit that outputs the image to the image forming unit. The operation accepting unit accepts an operation for setting a region of interest in the pre-passage image data and the post-passage image data,
The control unit determines that there is information that has disappeared when the information on the attention area of the pre-passage image data disappears in the attention area of the post-passage image data, and the attention area of the pre-passage image data The image forming apparatus according to claim 1, wherein the information is output to the output unit.   The control unit performs OCR processing of the pre-passage image data, stores text obtained by the OCR processing in the storage unit, and outputs the text corresponding to information disappeared after passing through the fixing unit to the output unit The image forming apparatus according to claim 1, wherein the image forming apparatus outputs the image to the image forming apparatus. A sheet reading unit that is provided in a conveyance path from the sheet feeding unit to the transfer unit and reads a conveyed sheet as the reading unit;
The control unit feeds a sheet set in the sheet feeding unit, causes the conveyance unit to convey the sheet, causes the sheet reading unit to read the sheet being conveyed, The image data obtained by reading is stored in the storage unit as the pre-passage image data, and the sheet is discharged after passing through the fixing unit after being read by the sheet reading unit, and is a reset sheet. Obtained by feeding the rear sheet, causing the conveyance unit to convey the post-passage sheet, causing the sheet reading unit to reread the post-passage sheet being conveyed, and reading the sheet reading unit. The image forming apparatus according to claim 1, wherein the image data of the post-passage sheet is stored in the storage unit as the post-passage image data.   The controller causes the image forming unit to form a toner image of an identification mark indicating that there is erased information, and causes the toner image of the identification mark to be transferred to the transfer unit on the post-passage sheet having the erased information. The image forming apparatus according to claim 4, wherein the fixing unit fixes the toner image of the identification mark. The reading unit includes an image reading device that reads a set document,
The control unit reads a sheet set on the image reading device, stores image data obtained by reading of the image reading device in the storage unit as the image data before passing, and the image before passing The acquired sheet, which is a sheet from which data has been acquired, is fed to the sheet feeding unit, the acquired sheet is transported to the transport unit, the acquired sheet is passed through the fixing unit, and the acquisition is performed. A post-passage sheet which is a finished sheet and is discharged once after passing through the fixing unit, and causes the image reading device to read the post-passage sheet data after passing the image data. The image forming apparatus according to claim 1, wherein the image forming apparatus stores the image data in the storage unit.   The image forming apparatus according to claim 1, wherein the output unit is one or both of the printing unit and a display unit that displays information. The image forming unit includes a protective layer forming unit that forms a transparent toner image for protecting the surface of the sheet using a transparent toner,
The operation receiving unit receives an operation of setting a protection area in the sheet,
The control unit causes the sheet set in the sheet feeding unit to be fed, transports the sheet to the transport unit, and causes the image forming unit to form a transparent toner image to be placed on the set protection area; The image forming apparatus according to claim 1, wherein a transfer of a transparent toner image to the protection area is performed by the transfer unit, and the transparent toner image is fixed by the fixing unit.

Images