JP2009269345A - Image forming apparatus and method for hiding image of printed paper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an image printed on a printed paper from b eing exposed to public attention. <P>SOLUTION: Dummy paper sheets D1, D2 and D3 printing transmission preventing images M1, M2 and M3 are discharged on the top recording paper sheets P subjected to face up paper discharge or below the bottom recording paper sheets P subjected to face down paper discharge so that a manuscript image I among the recording paper sheets P to which the manuscript image I is printed by a printing job is exposed to the outside when discharged to a paper discharge part and stacked. Then, the manuscript image I of the top recording paper sheet P and the bottom recording paper sheet P is masked by the transmission preventing image M1 of the dummy paper sheets D1 or overlapped with the transmission preventing images M2 and M3 of the dummy paper sheets D2 and D3 to be uniformly toned or subjected to blackout. Thus, contents cannot be recognized by viewing through the manuscript image I over the dummy paper sheets D1, D2 and D3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  According to the present invention, an image that is exposed on the surface of a printed paper that has been discharged to a paper discharge unit after printing an image by executing a print job is discharged to the paper discharge unit and stacked on the printed paper. The present invention relates to an image concealing method for a printed sheet concealed by a dummy sheet, and an image forming apparatus suitable for using this method.

  A printed sheet on which an image is printed by a print job is discharged to a paper discharge unit of the image forming apparatus. If the printed paper is left in the paper discharge unit for a while, the printed image is exposed to the public. In order to prevent this, face down paper discharge, in which the printed paper is discharged to the paper discharge section with the image printed side facing down, has been implemented. The expected effect cannot be achieved.

  In particular, the drop-on-demand ink jet system usually prints an image on the upper surface of the paper that passes under the image printing section, so that the surface on which the image is printed faces upward. In many cases, the paper is discharged face-up. For this reason, in order to perform face-down paper discharge with this type of image forming apparatus, it is necessary to provide means for turning the printed paper upside down in the apparatus, which is disadvantageous in terms of configuration and cost.

Therefore, in order to prevent the printed image from being exposed to the public, even if it is a printed paper that has been printed on both sides or a printed paper that has been printed by a face-up paper discharge image forming apparatus, Conventionally, a technique for discharging paper to an internal paper discharge tray (for example, Patent Document 1) and a technique for stacking white paper on printed paper and discharging the paper together to a paper discharge unit (for example, Patent Document 2) have been proposed. ing.
JP 11-42827 A JP 2005-169859 A

  Discharging the printed paper to the output tray inside the machine is particularly sensitive to the confidentiality of the image on the printed paper, especially when combined with technology that allows the printed paper to be removed from the output tray by entering an authentication code. Demonstrates a great effect on retention. Instead, the convenience is reduced by the amount of troublesome procedures and operations required to collect the printed paper from the discharge tray. Therefore, in order to adopt when priority is given to the convenience of collecting printed paper, it is inevitable that the technology is slightly inconsistent with the needs.

  On the other hand, stacking white paper on printed paper and discharging it together to the paper discharge unit prevents the printed image from being exposed to the public even when the paper discharge unit exists outside the apparatus. A certain effect is demonstrated above. However, there is a possibility that the image of the printed paper may be seen through the blank paper, and although it is convenient for collecting the printed paper, the printed paper image is not exposed to the public. It is hard to say that this is a sufficient measure.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to conceal an image of printed paper that is highly effective in preventing an image printed on the printed paper from being exposed to the public after being discharged. And a suitable image forming apparatus using the method.

  In order to achieve the above object, an image concealment method for printed paper according to the first aspect of the present invention includes a printed paper discharged to a paper discharge unit after printing an image on a paper by executing a print job. A printed sheet that is laminated with a dummy sheet discharged to the sheet discharge unit separately from the printed sheet, and conceals the image exposed on the surface of the printed sheet to the outside with the dummy sheet. In this image concealing method, the dummy paper is laminated with the printed paper on the dummy paper, the printing area on the paper when the image determined from the print job is printed on the paper. A first anti-transmission image that covers all in a state, and the dummy paper is superimposed on the image of the printed paper in a state of being laminated with the printed paper, and identifies the image in cooperation with the image Second to compose a composite image that cannot be Permeation preventive image, characterized by being adapted to print at least one of the light transmission preventing image of.

  In order to achieve the above object, the image forming apparatus of the present invention described in claim 6 includes a printed sheet discharged to a discharge unit after printing an image in the image printing unit by executing a print job, In the image forming apparatus, the dummy paper discharged to the paper discharge unit is stacked separately from the printed paper, and the image exposed on the surface of the printed paper is exposed to the outside by the dummy paper. Determining a transmission preventing image to be printed on the dummy paper based on the image determined from the print job; and printing the transmission preventing image determined by the determining unit in the image printing unit. Later, the dummy paper is discharged to the paper discharge unit in the order that the images exposed to the outside of the printed paper are concealed by the transmission preventing image. A dummy paper printing execution unit that causes the image printing unit to print the image for preventing transmission on paper, and the determining unit is configured to print the image determined from the print job on the paper. First setting means for setting the image for preventing transmission that covers all the print area on the paper in a state where the dummy paper is laminated with the printed paper, and the dummy paper is laminated with the printed paper. A second setting means for setting the anti-transmission image, which is superimposed on the image of the printed paper in a state of being formed, and forms a composite image in cooperation with the image and incapable of identifying the image; At least one of the first and second setting means, and the dummy paper printing execution means prints the transmission preventing image on the dummy paper set by at least one of the first and second setting means. The characterized in that to perform the image printing section.

  According to the image concealing method of the printed paper of the present invention described in claim 1 and the image forming apparatus of the present invention described in claim 6, the paper is discharged to the paper discharge unit separately from the printed paper and printed. A transmission preventing image is printed on a dummy sheet laminated with the finished sheet. The transmission preventing image is based on at least one of the print area of the image on the printed paper and the content of the image printed on the printed paper.

  Specifically, the transmission preventing image printed on the dummy paper includes a first transmission preventing image that covers the entire print area of the image on the printed paper in a state where the dummy paper is laminated with the printed paper; At least one of the second anti-transmission images that are superimposed on the image of the printed paper and that forms a composite image that cannot be identified in cooperation with the image.

  Therefore, when the dummy paper is stacked on the printed paper of the paper discharge unit, the image exposed to the outside of the printed paper is all masked with the first transmission preventing image, or the image of the printed paper And the second anti-transmission image superimposed thereon, the printed paper image cannot be identified independently, and at least one of the printed paper image content is a dummy. It is in a state where it cannot be read through the watermark through the paper, that is, a state where the image on the printed paper cannot be recognized independently.

  For this reason, even if the printed paper is discharged to a paper discharge unit outside the apparatus, it is possible to prevent the image printed on the surface of the printed paper from being exposed and exposed to the public.

  The image concealment method for printed paper of the present invention described in claim 2 is the image concealment method of the present invention described in claim 1, wherein the second transmission preventing image is determined from the print job. The reverse distribution image having a print density or print density distribution opposite to the print density or print density distribution on the paper when the image is printed on the paper, and the image discriminated from the print job And a complementary color distribution image having a complementary color distribution to the color distribution on the paper when printing on the paper.

  The image forming apparatus of the present invention described in claim 7 is the image forming apparatus of the present invention described in claim 6, wherein the second setting means determines the image discriminated from the print job as the sheet. A reverse distribution image setting means for setting a reverse distribution image having a print density or print density distribution opposite to the print density or print density distribution on the paper at the time of printing to the image for preventing transmission, A complementary color distribution that sets a complementary color distribution image having a complementary color distribution to the color distribution on the paper when the image determined from the print job is printed on the paper is set as the transmission preventing image. And image setting means.

  According to the image concealing method for printed paper of the present invention described in claim 2, the image concealing method for printed paper of the present invention described in claim 1 and the image of the present invention described in claim 7 are also provided. According to the forming apparatus, in any of the image forming apparatuses according to the sixth aspect of the present invention, the anti-transmission image that forms the composite image by being superimposed on the image on the printed paper is an image on the printed paper. The content is based on at least one of the print density or the print density and the color distribution on the printed paper.

  Specifically, a reverse distribution image having a print density or print density distribution opposite to the image on the printed paper, and a complementary color distribution image having a color distribution complementary to the color distribution of the image on the printed paper, Of these, at least one of them.

  Therefore, a composite image in which the print density or the print density is uniformed is configured by the image of the printed paper and the reverse distribution image having a print density or print density distribution opposite to this, or printing. The image of the printed paper is composed of at least one of the image of the finished paper and the complementary color distribution image of the color distribution having a complementary color relationship with the color distribution. The content is in a state where it cannot be read through the dummy paper, that is, the image on the printed paper cannot be independently recognized.

  For this reason, the image of the printed paper discharged to the paper discharge unit outside the apparatus is surely secured by the transmission preventing image of the dummy paper that is stacked on the printed paper and discharged to the paper discharge unit and superimposed on the image. , Can be unrecognizable independently.

  The image concealment method for printed paper of the present invention described in claim 3 is the image concealment method for printed paper of the present invention described in claim 2, wherein when the complementary color distribution image is printed on the dummy paper, When the complementary color distribution image is one that can be printed on the dummy paper by single color printing of two or more ink colors among a plurality of ink colors used for printing the image, single color printing of ink color with the largest remaining amount The complementary color distribution image is printed on the dummy paper.

  An image forming apparatus according to an eighth aspect of the present invention is the image forming apparatus according to the seventh aspect of the present invention, wherein the complementary color distribution image is two of a plurality of ink colors used for printing the image. When the ink can be printed on the dummy paper by the single color printing of the ink color, the complementary color distribution image setting unit sets the complementary color distribution image to the one by the single color printing of the ink color having the largest remaining amount. It is characterized by that.

  According to the image concealing method of the printed paper of the present invention described in claim 3, the image concealing method of the printed paper of the present invention described in claim 2 and the image of the present invention described in claim 8 are also provided. According to the forming apparatus, in the image forming apparatus of the present invention described in claim 6, any of the plurality of ink colors used for printing the image can be printed by monochromatic printing of two or more ink colors. Is printed on a dummy sheet, only the ink color with the largest remaining amount is used for printing the complementary color distribution image.

  Therefore, it is possible to minimize the occurrence of a situation where printing of the complementary color distribution image on the dummy paper actively consumes a small amount of ink and makes it impossible to print the image on the paper due to running out of only a specific color. can do.

  The image concealment method for printed paper of the present invention described in claim 4 is the image concealment method for printed paper of the present invention described in claim 1, 2, or 3, wherein the print job is processed, and after the processing When the print job is executed, the image is printed on the sheet, the transmission preventing image is printed on the dummy sheet, and the dummy sheet is printed on the discharge unit after the transmission preventing image is printed. It is characterized by having performed.

  The image forming apparatus of the present invention described in claim 9 is the image forming apparatus of the present invention described in claim 6, 7 or 8, wherein the dummy paper print execution means processes the print job, The image printing unit is configured to print the transmission preventing image on the dummy paper based on the processed print job.

  According to the image concealing method of the printed paper of the present invention described in claim 4, the image concealing method of the printed paper of the present invention described in claim 1, 2, or 3, and also described in claim 9 According to the image forming apparatus of the present invention, in any of the image forming apparatuses of the present invention described in claim 6, 7, or 8, printing of an image on a sheet and dummy processing are performed only by processing a print job. The printing of the anti-transmission image on the paper and the discharge of the dummy paper that is stacked at a position to conceal the image on the surface of the printed paper discharged to the paper discharge unit to one paper discharge All are realized by executing the print job.

  For this reason, it is not necessary to newly generate and execute a print job different from the print job for printing the image on the paper in order to print the transmission preventing image on the dummy paper. Can be suppressed.

  The image concealment method for printed paper of the present invention described in claim 5 is the image concealment method for printed paper of the present invention described in claim 1, 2, 3 or 4, wherein the printed paper and the dummy paper Are temporarily discharged to an internal paper discharge unit and stacked, and the stacked printed paper and the dummy paper are collectively discharged to the paper discharge unit.

  An image forming apparatus according to a tenth aspect of the present invention is the image forming apparatus according to the sixth, seventh, eighth, or ninth aspect, wherein the image forming apparatus is disposed inside the image forming apparatus, and the dummy paper printing execution unit is provided. The dummy paper on which the anti-transmission image is printed and the printed paper are discharged and stacked, and the printed paper and the dummy paper stacked in the internal paper discharge section are stacked. The apparatus further includes a paper discharge unit that collectively discharges the paper to the paper discharge unit, and the paper discharge unit is disposed outside the image forming apparatus.

  According to the image concealing method of the printed paper of the present invention described in claim 5, in the image concealing method of the printed paper of the present invention described in claim 1, 2, 3 or 4, and According to the image forming apparatus of the present invention described above, in any of the image forming apparatuses of the present invention described in claim 6, 7, 8 or 9, the printed sheet is printed by the transmission preventing image by discharging the dummy sheet. Until the image is concealed, the printed paper is discharged to an internal paper discharge unit inside the image forming apparatus. Therefore, at the stage where the laminated dummy paper and the printed paper are collectively discharged to the paper discharge unit outside the image forming apparatus, the image exposed on the surface of the printed paper is the dummy paper. It is in a state of being concealed by the transmission preventing image.

  For this reason, the batch discharge of the printed paper and the dummy paper discharged to the internal paper discharge unit to the paper discharge unit outside the image forming apparatus is performed regardless of whether or not the user approves. However, it is possible to prevent the image located on the surface of the printed paper from being exposed to the public between the time when printing of the transmission preventing image on the dummy paper is executed and the dummy paper is discharged. be able to.

  According to the present invention, even when printed paper is discharged to a paper discharge unit disposed outside the image forming apparatus, the image printed on the surface of the printed paper is exposed and exposed to the public. Can be prevented.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is an explanatory diagram showing a schematic configuration of an ink jet recording apparatus according to a first embodiment of an image forming apparatus according to the present invention.

  As shown in FIG. 1, the inkjet recording apparatus 1 according to the present embodiment reads a document image on a document and outputs an image signal, and a recording paper (based on the image signal output from the scanner unit 101). The original image is printed (recorded) on the recording surfaces P1 and P2 of P (refer to FIG. 2B, the front surface P1, or both the front surface P1 and the back surface P2). Printer unit 102 (corresponding to the image printing unit in the claims).

  Further, the ink jet recording apparatus 1 of the present embodiment is provided inside the casing of the ink jet recording apparatus 1 from the paper feeding unit 105 to the internal tray 109a (corresponding to the internal paper discharge unit in the claims) via the printer unit 102. The belt transport unit 106 for transporting the recording paper P, the double-sided belt transport unit 107, the double-sided stack tray 108, the transport path 112, and the recording paper P once discharged to the internal tray 109a are collectively collected. A paper discharge unit 109 disposed outside the housing of the inkjet recording apparatus 1 to be discharged, a display 110 for performing various input settings and information display, a control unit 10 for overall control (see FIG. 11), etc. It has.

  The scanner unit 101 photoelectrically reads an original image I on an original M (see FIG. 2A), and performs 8-bit digital of R component, G component, and B component of each pixel constituting the original image I. A signal is output. The scanner unit 101 includes a document reading unit 101a and an automatic document feeder (hereinafter referred to as ADF or ADF unit) 101b.

  In the document reading unit 101a, an optical image of the document image I from one or a plurality of documents M set on the document set tray of the ADF unit 101b or a document M placed on a document placement glass stand (not shown). Reading can be performed. The document image I read from the document M by the scanner unit 101 can be printed on the recording surface P1 (or recording surfaces P1, P2) of the recording paper P by the inkjet head unit 104.

  As shown in FIG. 3, the printer unit 102 includes a control board 103 and an inkjet head unit 104. In the printer unit 102, printing is performed by a print job that is input from the outside of the inkjet recording apparatus 1 to a control unit 10 (see FIG. 11) described later via a printer server (not shown) or the like. This print job includes data such as a document image I (see FIG. 2A) to be printed on the recording surface P1 (or recording surfaces P1 and P2) of the recording paper P, the document size, and the number of pages.

  Then, the printer unit 102 is conveyed in the direction of arrow b by the belt conveyance unit 106 from the paper feeding unit 105 using a digital image signal generated by the control board 103 based on the data of the original image I of the input print job. The original image I is printed by the inkjet head unit 104 on the recording surface P1 (or recording surfaces P1, P2) of the recording paper P. That is, in the present embodiment, the document image I corresponds to a predetermined image in the claims.

  In addition, when performing single-sided printing on the recording paper P, the recording paper P is transported to the internal tray 109a by the belt transport unit 106, and further transported to the paper discharge unit 109 for discharge. On the other hand, when double-sided printing is performed on the recording paper P, the recording paper P that has been printed on one side (for example, the front surface P1) is linked with the belt conveyance unit 106, the conveyance path 112, and the double-sided belt conveyance unit 107. Are continuously conveyed from the direction of the arrow b to the direction of the arrow c in a reverse state, and are discharged to the double-sided stack tray 108 once. Then, the recording paper P is conveyed again to the inkjet head unit 104 by the belt conveyance unit 106, and an image is printed on the remaining one side (for example, the back surface P2). The recording paper P that has been printed on both sides is transported to the internal tray 109a by the belt transport unit 106, and further transported to the paper output unit 109 and discharged, as in the case of single-sided printing.

  As shown in FIG. 4, the inkjet head unit 104 is a recording head corresponding to each component of a digital image signal of a Y (yellow) component, an M (magenta) component, a C (cyan) component, and a K (black) component. 40 to 43 and a head driver 44 for driving the recording heads 40 to 43 are provided.

  In the control board 103 shown in FIG. 3, one original image I in an input print job is stored in the form of a digital image signal, and predetermined image processing is performed on the digital image signal. The processed digital image signal is output to the inkjet head unit 104. For this purpose, the control board 103 includes a storage unit 113, a color image processing unit 133, a signal conversion unit 123, and an ink amount setting unit 143 for setting the ink amount, as shown in FIG.

  The storage unit 113 performs digital signal signals of R (red) component, G (green) component, and B (blue) component, and predetermined signal processing for a document image I for one input print job. The applied digital image signal is stored.

  The color image processing unit 133 converts the digital image signals of R component, G component, and B component stored in the storage unit 113 into digital image signals of Y component, M component, C component, and K component. .

  The signal conversion unit 123 converts each pixel data in the digital image signal of Y component, M component, C component, and K component into 3-bit data by the color image processing unit 133.

  The ink amount setting unit 143 sets an ink amount when ink is ejected based on the 3-bit pixel data converted by the signal conversion unit 123. The ink amount set by the ink amount setting unit 143 also varies depending on the density specified by the operator on the display 110.

  The storage unit 113 includes a frame memory 30 that stores digital image signals of R component, G component, and B component relating to the original image I for one sheet of the input print job, and a color image processing unit. The working memory 31 for storing the digital image signals of the Y component, M component, C component, and K component converted by 133, and the Y component, M component, and C for which the ink amount is set by the ink amount setting means 143 And a drive memory 32 for storing digital image signals of components and K components.

  Specifically, the digital image signal converted into the R component, the G component, and the B component relating to the original image I by the input print job is stored in the frame memory 30 for each component one by one. .

  Then, in response to this print instruction, pixel data of a digital image signal relating to one original image I stored in the frame memory 30 is output to the color image processing unit 133 at the R component, G component, and B component. Are converted into Y component, M component, C component, and K component, binarized, and stored in the working memory 31.

  The pixel data of the Y component, M component, C component, and K component binarized as described above is converted into 3-bit data by the signal conversion unit 123 for each component, and is again stored in the working memory 31. Stored for each component.

  Through the above processing, processed digital image data of a digital image signal relating to one original image I is generated and stored in the working memory 31 for each component. The processed digital image signal for each component stored in the working memory 31 is stored in the drive memory 32. The processed digital image signal stored in the drive memory 32 is output to the inkjet head unit 104 at a predetermined timing.

  Then, the processed digital image signal for each component is input to the head driver 44 shown in FIG. 4, and the head driver 44 outputs the processed digital image signal to the recording heads 40 to 43 corresponding to the respective components. The recording heads 40 to 43 are made to eject ink at a predetermined timing synchronized with the conveyance speed of the recording paper based on the processed digital image data.

  The processing as described above is performed in synchronization with the conveyance of the recording paper P from the paper supply unit 105 of FIG. 3 to the inkjet head unit 104 described above, and the ink ejected from the recording heads 40 to 43 is recorded. The original image I is transferred to the paper P and printed on the recording surface P1 (or recording surfaces P1, P2) of the recording paper P.

  The internal tray 109a has an opening / closing door 111a, and the recording paper P or the like conveyed and discharged to the internal tray 109a while the opening / closing door 111a is closed as shown in FIG. By releasing 111a (indicated by an imaginary line in FIG. 3), the recording paper P or the like is discharged to the discharge unit 109 by its own weight or by a conveying means (not shown).

  As is apparent from the layout of the printer unit 102 in FIG. 3 and the like, in the inkjet recording apparatus 1 of this embodiment, the printed recording paper P is discharged face-up to the paper discharge unit 109.

  The display 110 is disposed at the top of the printer unit 102 together with the scanner unit 101. A touch sensor (not shown) is attached to the screen of the display 110. By this touch sensor, it is possible to detect the pressing operation of each button displayed on the display 110.

  FIG. 6 is an explanatory diagram showing an operation screen configured by display on the display 110 provided in the inkjet recording apparatus 1. A basic menu screen shown in FIG. 6 is displayed on the display 110 as a default screen. This basic menu screen has an area for displaying the current setting status and sensor detection status on the left side, a counter for displaying the number of prints on the right side, a numeric keypad for entering and setting the number of prints, and print density. An automatic density button for automatically setting, a density input gauge for manually inputting and setting the print density, and an area for displaying each key for printing start and stop.

  Specifically, what is displayed in the left area of the basic menu screen is the orientation of the document (not shown) with respect to the ADF unit 101b when using the scanner unit 101 (vertical orientation (original table / AF), landscape orientation) (Original platen / AF)), the size and orientation of a document set on the scanner unit 101 or a document specified by data in an external print job (for example, A4 portrait, A4 landscape, B5 portrait), The size and orientation of the recording paper P on which the original image I is printed (for example, A4 portrait, A4 landscape, B5 portrait, etc.), printing magnification (same size, enlargement, reduction, magnification% display), and sorting of the printed recording paper P Menu setting state, confidential document paper discharge menu setting state (ON (mask), ON (tone equalization), ON (blackout), OFF), paper discharge menu setting for recording paper P on which document image I is printed) State (collective waste paper, usually paper ejection) is.

  Among these, the input setting content related to the original setting direction is displayed in the original setting direction area with respect to the scanner unit 101. The displayed content can be input and set on each setting screen (not shown) relating to the document set orientation displayed hierarchically on the display 110 by pressing the rightmost setting button.

  Next, in the area of the size and orientation of the document on the basic menu screen of FIG. 6, those contents detected by the sensor of the ADF unit 101b and those contents defined by the data in the print job are displayed. .

  Subsequently, in the area of the size and orientation of the recording paper P on which the original image I is printed on the basic menu screen of FIG. 6, the contents (for example, for example, detected by the paper sensor 546 of the paper feeding unit 105 shown in FIG. A4 vertical, A4 horizontal, B5 vertical, etc.) are displayed.

  Next, in the print magnification area in the basic menu screen of FIG. 6, the input setting contents relating to what magnification the original image I is printed on the recording paper P are displayed. The displayed content can be input and set on a setting screen (not shown) relating to the printing magnification displayed on the display 110 by pressing the rightmost setting button.

  Subsequently, in the sort menu setting state area in the basic menu screen of FIG. 6, the input setting contents relating to the sorting of the recording paper P after the document image I is printed are displayed. The displayed contents can be input and set on a setting screen (not shown) relating to sorting that is switched and displayed on the display 110 by pressing the setting button at the right end.

  Next, in the area for the confidential document discharge setting state in the basic menu screen of FIG. 6, recording after the original image I is printed when the original image I is a confidential document (content with confidentiality). The input setting contents relating to the paper discharge of the paper P are displayed. The displayed content is input and set on a setting screen related to confidential document discharge that is displayed on the display 110 by pressing the setting button at the right end.

  Specifically, by pressing the confidential document discharge setting button, the display on the display 110 is first switched from the basic menu screen of FIG. 6 to the confidential document discharge setting screen of FIG. In this confidential document discharge setting screen, since the original image I is a confidential document, the recording paper P is used as a dedicated discharge method, or because the original image I is not a confidential document, the recording paper P is discharged normally. And whether to select a dedicated paper discharge method among three modes (mask mode, tone uniformization mode, blackout mode) as a dedicated paper discharge method. .

  If the cancel button is pressed on the confidential document discharge setting screen, the confidential document discharge performed on the confidential document discharge setting screen of FIG. 7 after the display 110 is switched from the basic menu screen of FIG. All of the input setting contents related to is canceled, and the display on the display 110 is switched to the basic menu screen of FIG.

  On the other hand, when the mask mode ON button is pressed on the confidential document discharge setting screen of FIG. 7, a dummy sheet for masking one sheet before and after one or a plurality of recording sheets P printed by one print job. A mask mode for discharging D1 (reference) is selected. In addition, when the ON button of the tone uniform mode is pressed on the confidential document discharge setting screen, a tone uniform dummy is printed one by one before and after one or a plurality of recording sheets P printed by one print job. A tone uniformity mode for discharging the paper D2 (reference) is selected. Furthermore, when the ON button in the blackout mode is pressed, black sheets for discharging blackout dummy paper D3 (reference) one sheet before and after one or a plurality of recording sheets P printed by one print job are discharged. Out mode is selected.

  When the confidential document discharge setting button on the lower left of the confidential document discharge setting screen is pressed, a normal discharge mode in which dummy paper is not discharged other than one or a plurality of recording sheets P printed in one print job is selected. The

  The contents input and set on the confidential document discharge setting screen of FIG. 7 are canceled by pressing the cancel button at the lower right of the screen, and are confirmed by pressing the confirm button. In either case, the display 110 returns to the basic menu screen of FIG. When the display 110 returns to the basic menu screen of FIG. 6 by pressing the confirmation button on the confidential document discharge setting screen of FIG. 7, the confidential document discharge menu of FIG. The contents set on the setting screen (ON (mask, uniform tone, blackout), OFF) are displayed.

  A dedicated paper discharge method that can be set by selecting one of the modes on the confidential document paper discharge setting screen in FIG. 7 will be described with reference to FIGS.

  First, it is assumed that an original image I having confidential content is printed on one or a plurality of recording papers P by one print job. Here, when the recording paper P (in this case, a plurality of sheets) is discharged face up and stacked after printing by one print job, as shown in FIG. At the top, the original image I printed on the recording paper P is exposed. Similarly, when the recording paper P (in this case, a plurality of sheets) is ejected face-down and stacked after printing by one print job, as shown in FIG. At the bottom, the original image I printed on the recording paper P is exposed.

  Therefore, when one of the modes is selected on the confidential document discharge setting screen of FIG. 7, as shown in FIGS. 8A and 8B, the top of the stacked recording sheets P or the stacked layers The dummy paper D1 (D2, D3) on which the transmission preventing image M1 (M2, M3) is printed is discharged so as to be positioned below the lowermost recording paper P. Therefore, in order to view the original image I on the uppermost or lowermost recording paper P, the original image I can only be seen through the dummy paper D1 (D2, D3) discharged above or below it.

  Here, as shown in FIGS. 8A and 8B, dummy papers D1, D2, and D3 to be discharged are classified into three modes that can be set on the confidential document discharge setting screen of FIG. A description will be given with reference to a) to (d).

  First, it is assumed that an original image I having four screen areas R1 to R4 shown in FIG. 9A is printed at the beginning or end of one or a plurality of recording sheets P printed by one print job. . Here, the screen area R1 is an area printed with low print density, low print density, and red, and the screen area R2 is an area printed with high print density, low print density, and blue, and the screen area R3. Is an area printed with a low print density, a high print density, and green, and the screen area R4 is an area printed with a high print density, a high print density, and black.

  In contrast, in the mask mode, as shown in FIG. 9B, a transmission preventing image M1 having a size covering the entire original image I of the recording paper P (the first transmission preventing image in the claims). The dummy paper D1 printed with (corresponding to an image) is discharged. The content of the anti-transmission image M1 may be random characters or symbols, or may be a large number of dots arranged in a matrix or a solid black image.

  In the mask mode, the dummy paper D1 on which such a transmission preventing image M1 is printed is placed on the uppermost recording paper P stacked as shown in FIGS. 8A and 8B, or By discharging the paper so that it is positioned below the lowermost recording paper P, the original image I of the uppermost or lowermost recording paper P is transmitted through the upper or lower dummy paper D1. It is completely covered by the prevention image M1.

  Therefore, the original image I on the uppermost or lowermost recording paper P is no longer visible due to the presence of the transmission preventing image M1, and the content is recognized by seeing through the dummy paper D1. Can not be.

  In the uniform tone mode, as shown in FIG. 9C, a dummy sheet on which a transmission preventing image M2 having four screen areas T1 to T4 (corresponding to the reverse distribution image in the claims) is printed. D2 is discharged. The screen areas T1 to T4 of the transmission preventing image M2 are arranged in positions overlapping the four screen areas R1 to R4 of the original image I of the recording paper P in a state where the screen areas T1 to T4 are stacked with the recording paper P.

  Here, the transmission preventing image M2 on the dummy paper D2 has a printing density and printing density distribution opposite to that of the original image I on the recording paper P. Specifically, the screen area T1 of the transmission preventing image M2 is printed at a high print density and high print density, which are printing characteristics opposite to the print density and print density of the screen area R1 of the corresponding document image I.

  Similarly, the other screen areas T2 to T4 of the transmission preventing image M2 are printed with printing characteristics opposite to the printing density and printing density of the screen areas R2 to R4 of the corresponding document image I, respectively. That is, the screen area T2 is printed with a low print density and a high print density, the screen area T3 is printed with a high print density and a low print density, and the screen area T4 is printed with a low print density and a low print density.

  Note that the printing colors of the screen areas T1 to T4 of the transmission preventing image M2 are arbitrary. However, due to subtractive color mixing, each screen of the transmission preventing image M2 is a color that is the same color or a color that is adjacent to the color on the hue circle with respect to the printing colors of the corresponding screen regions R1 to R4 of the original image I. It is more effective to print the regions T1 to T4.

  The print density and the print density can be adjusted as appropriate according to the number of ink drops per dot and the dot pitch (resolution).

  In the tone uniform mode, the dummy paper D2 on which such a transmission preventing image M2 is printed is placed on the uppermost recording paper P stacked as shown in FIGS. 8 (a) and 8 (b). Alternatively, by discharging the paper so that it is positioned below the bottommost recording paper P, the screen areas R1 to R4 of the original image I of the top and bottom recording paper P are displayed on the screen areas R1 to R4. The corresponding screen areas T1 to T4 of the upper and lower dummy sheets D2 overlap each other.

  Then, the low print density screen areas R1 and R3 of the original image I include the high print density screen areas T1 and T3 of the transmission preventing image M2 of the dummy paper D2, and the high print density screen area R2 of the original image I. On R4, screen regions T2 and T4 having a low print density of the transmission preventing image M2 on the dummy paper D2 are overlapped.

  Thus, when the document image I and the transmission preventing image M2 are overlapped, the portion where the screen region R1 and the screen region T1 overlap, the portion where the screen region R2 and the screen region T2 overlap, the screen region R3 and the screen region T3. Are overlapped with each other and the portion where the screen region R4 and the screen region T4 are overlapped with each other, the high print density image and the low print density image are overlapped.

  Further, in the screen areas R1 and R2 of the original image I having a low printing density, the screen areas T1 and T2 having a high printing density of the transmission preventing image M2 of the dummy paper D2 are included in the screen areas R3 and 3 of the original image I having a high printing density. On R4, screen regions T3 and T4 having a low printing density of the transmission preventing image M2 on the dummy paper D2 are overlapped.

  Thus, when the document image I and the transmission preventing image M2 are overlapped, the portion where the screen region R1 and the screen region T1 overlap, the portion where the screen region R2 and the screen region T2 overlap, the screen region R3 and the screen region T3. Are overlapped with each other and the portion where the screen region R4 and the screen region T4 overlap with each other, the high print density image and the low print density image overlap each other.

  Accordingly, the portion where the screen region R1 and the screen region T1 overlap, the portion where the screen region R2 and the screen region T2 overlap, the portion where the screen region R3 and the screen region T3 overlap, and the screen region R4 and the screen region T4. The gap of the print density between the overlapping portions is virtually eliminated visually.

  Therefore, the original image I on the top and bottom recording paper P can no longer be viewed only as a uniform tone image with no print density density or print density density due to the presence of the transmission preventing image M2. End up. That is, the document image I and the transmission preventing image M2 are visually recognized as a single image having a uniform tone. Therefore, the original image I and the transmission preventing image M2 cannot be distinguished and recognized.

  Next, in the blackout mode, as shown in FIG. 9D, a dummy sheet on which a transmission preventing image M3 (corresponding to the complementary color distribution image in the claims) having four screen areas H1 to H4 is printed. D3 is discharged. The screen areas H1 to H4 of the transmission preventing image M3 are arranged at positions overlapping the four screen areas R1 to R4 of the original image I on the recording paper P in a state where the screen areas are stacked with the recording paper P.

  Here, the transmission preventing image M3 of the dummy paper D3 has a color distribution that is complementary to the color distribution of the original image I of the recording paper P. Specifically, the screen area H1 of the transmission preventing image M3 is printed in blue (green is also acceptable) that is complementary to the red color that is the print color of the screen area R1 of the corresponding document image I.

  Similarly, the screen areas H2 and H3 of the transmission preventing image M3 are blue, which is the printing color of each of the screen areas R2 and R3 of the corresponding document image I, green (which may be red) complementary to green, and red (blue). But it is also possible to print each. The screen area T4 of the transmission preventing image M3 corresponding to the screen area R4 of the original image I printed in black can be printed in any color, but in this embodiment, it is printed in black. And

  In the blackout mode, the dummy paper D3 on which such a transmission preventing image M3 is printed is placed on the uppermost recording paper P stacked as shown in FIGS. 8A and 8B, or By discharging the paper so that it is positioned below the bottommost recording paper P, the upper and lower recording papers P are placed on the screen areas R1 to R4 of the original image I. And the corresponding screen areas H1 to H4 of the lower dummy paper D3 overlap each other.

  Then, in the screen area R1 printed in red of the original image I, the screen area H1 printed in blue of the transmission preventing image M3 of the dummy paper D3 is in the screen area R2 printed in blue of the original image I. A screen area H2 printed in green of the transmission preventing image M3 on the dummy paper D3 and a screen area R3 printed in green of the original image I are printed in red of the transmission preventing image M3 on the dummy paper D3. The area H3 printed in black on the original image I is overlapped with the screen area H4 printed in black on the transmission preventing image M4 on the dummy paper D3.

  Thus, when the document image I and the transmission preventing image M3 are overlapped, the screen area R1 and the screen area H1 overlap, the screen area R2 and the screen area H2 overlap, and the screen area R3 and the screen In all of the portions where the region H3 overlaps, two colors whose print colors are complementary to each other overlap, and a blackout state in which black is visually recognized due to subtractive color mixture occurs.

  Accordingly, even if the screen area R4 of the original image I originally printed in black and the screen area H4 of the anti-transmission image M3 overlap each other, an attempt is made to see the original image I through the anti-transmission image M3. , The entire image becomes visible only in black. That is, the document image I and the transmission preventing image M3 are visually recognized as a single black image. Therefore, the original image I and the transmission preventing image M2 cannot be distinguished and recognized.

  It should be noted that the anti-transmission images M1, M2, and M3 are printed on the dummy papers D1, D2, and D3 discharged by selecting the mask, tone uniformization, and blackout modes described above. This is performed in the head unit 104. In addition, the transmission preventing images M1, M2, and M3 are printed by a control unit 10 (see FIG. 5) that prints a print job indicating a print request for the original image I on the recording paper P that is the target of stacking the dummy papers D1, D2, and D3. 11) is processed and processed, and is executed as a part of the processed print job. Details of the processing performed by the control unit 10 will be described later with reference to FIGS.

  Returning to the explanation of the operation screen displayed on the display 110, in the area for setting the paper discharge menu in the basic menu screen of FIG. 6, the recording paper P on which the original image I is printed and the transmission preventing image M1 are displayed. , M2 and M3 are displayed, and the input setting contents regarding the discharge of the dummy papers D1, D2 and D3 are displayed. The displayed contents are input and set on a setting screen related to paper discharge that is switched and displayed on the display 110 by pressing the setting button at the right end. However, this input setting is effective only in a state in which the paper discharge mode dedicated to the confidential document among the above-described mask mode, tone uniformization mode, and blackout mode is set.

  Specifically, the display 110 is first switched from the basic menu screen in FIG. 6 to the paper discharge setting screen in FIG. 10 by pressing the paper discharge setting button. In this paper discharge setting screen, the recording paper P (one or a plurality of sheets) for one print job on which the original image I is printed, and the dummy papers D1, D2, D3 on which the transmission preventing images M1, M2, M3 are printed are displayed. In addition, it is set to input whether to perform batch discharge or normal discharge.

  When the batch discharge (batch discharge ON) setting is input on the discharge setting screen, the recording paper P (one or a plurality of sheets) and the dummy papers D1, D2, and D3 are ink-jetted until printing for one print job is completed. When the recording paper P is transported to the internal tray 109a of the recording apparatus 1, the recording paper P and the dummy papers D1, D2, and D3 are collectively discharged to the paper discharge unit 109 after the print job is completed. Is called. On the other hand, if the input setting is set to not batch discharge (batch discharge OFF), the internal tray 109a is made to pass through the opening of the open / close door 111a and the recording paper P or the dummy paper D1 printed by the inkjet head unit 104 is transmitted. Normal discharge is performed in which the prevention image M1 is discharged to the discharge unit 109 one sheet at a time.

  The contents input and set on the paper discharge setting screen of FIG. 10 are canceled by pressing the cancel button at the lower right of the screen, and are confirmed by pressing the confirm button. In either case, the display 110 returns to the basic menu screen of FIG. When the display 110 returns to the basic menu screen of FIG. 6 by pressing the enter button on the paper discharge setting screen of FIG. 10, the input setting is made on the paper discharge setting screen of FIG. The contents (batch delivery, normal delivery) are displayed.

  The operation of each part of the inkjet recording apparatus 1 described above is controlled by a CPU 90 (see FIG. 11) provided in the control unit 10 described later.

  FIG. 11 is a block diagram showing a schematic configuration of a control unit provided in the ink jet recording apparatus of FIG.

  As shown in FIG. 11, the control unit 10 of the inkjet recording apparatus 1 includes a CPU 90. The CPU 90 controls the operation of the scanner unit 101 and the printer unit 102 according to the contents input and set from the display 110 based on the program and setting information stored in the ROM 91. The CPU 90 is provided with a RAM 92, and the RAM 92 stores the number of prints input from the display 110 and various setting contents as needed.

  In the inkjet recording apparatus 1, when an external print job is input, the original image I is recorded by the printer unit 102 under the control of the CPU 90 of the control unit 10 in accordance with the data of the original image I in the print job. Printing is performed on the recording surface P1 (or recording surfaces P1, P2) of the paper P. In addition, when the confidential document discharge setting screen of the display 110 is set to a discharge mode (one of mask mode, tone uniformization mode, and blackout mode) dedicated to confidential documents, an image for preventing transmission (transmission) Any one of the prevention images M1, M2, and M3) is printed on the recording surface P1 of the recording paper P by the printer unit 102, and a dummy paper (any one of the dummy papers D1, D2, and D3) is printed. These recording sheets P (or the recording sheets P and the dummy sheets D1, D2, D3) are discharged to the discharge unit 109 via the internal tray 109a.

  Hereinafter, a procedure of processing performed by the CPU 90 of the control unit 10 of the inkjet recording apparatus 1 for performing such printing will be described with reference to flowcharts of FIGS. 12 to 14.

  First, after the power of the inkjet recording apparatus 1 is turned on, the CPU 90 determines whether or not a print job has been input as shown in FIG. 12 (step S1). If the print job has not been input (step S1). NO), the process proceeds to step S51 described later. On the other hand, if a print job is input (YES in step S1), it is determined whether any one of the confidential document discharge mode of the mask mode, the tone uniform mode, and the blackout mode is set (step S3). ). If the confidential document discharge mode is not set (NO in step S3), the process proceeds to step S47 described later.

  On the other hand, if the confidential document discharge mode is set (YES in step S3), it is determined whether batch discharge is set (step S5). If not set (NO in step S5), the process proceeds to step S11 described later. On the other hand, if batch discharge is set (YES in step S5), the open / close door 111a of the opened internal tray 109a is closed (step S7), and then the batch discharge flag area flag F5 of the RAM 92 is set. (Default = “0”) is set to “1” (step S9). Thereafter, the process proceeds to step S11.

  In step S11, when the print job of the original image I by the print job is finished on the recording paper P from the contents of the input print job and the recording paper P is discharged and stacked on the paper discharge unit 109, it is stacked. It is determined whether the original image I is exposed on the recording paper P which is the uppermost recording paper P, the lowermost recording paper P, or both of the recording papers P stacked.

  When it is determined that the original image I is exposed only by the topmost recording paper P (U in step S11), the flag F1 (default = “0”) in the upper exposure flag area of the RAM 92 is set to “1”. After setting (step S13), the process proceeds to step S19 described later. If it is determined that the original image I is exposed only with the bottommost recording paper P (B in step S11), the flag F3 (default = “0”) in the lower exposure flag area of the RAM 92 is set to “1”. ”(Step S15), the process proceeds to step S19. Further, when it is determined that the original image I is exposed on both the uppermost recording paper P and the lowermost recording paper P (UB in step S11), the upper exposure flag F1 and the lower exposure flag F3. After both are set to “1” (step S17), the process proceeds to step S19.

  As shown in FIG. 13, in step S19, it is determined whether or not the lower exposure flag F3 is “1”. If it is not “1” (NO in step S19), the process proceeds to step S27 described later. . On the other hand, if the lower exposure flag F3 is “1” (YES in step S19), the first print that is stacked at the bottom of the paper discharge unit 109 after printing the input print job is executed. For the original image I of the recording paper P to be printed, the data in the print job is analyzed, and the anti-transmission image (any of the anti-transmission images M1, M2, M3) according to the set confidential document discharge mode Get information necessary for printing. Then, based on the acquired information, data of an anti-transmission image (any one of the anti-transmission images M1, M2, M3) corresponding to the set confidential document discharge mode is generated, and based on the generated data A print job for inserting the print of the image for preventing transmission at the beginning is processed (step S21).

  Subsequently, based on the processed print job, the transmission preventing image is printed on one recording sheet P in the inkjet head unit 104 (step S23). Subsequently, the dummy paper (any one of the dummy papers D1, D2, D3) generated by the printing is conveyed toward the internal tray 109a (step S25). Thereafter, the process proceeds to step S27.

  In step S27, printing of the original image I on the recording paper P by the input print job is performed in the inkjet head unit 104 by the number of sheets specified by the printing job, and the printed recording paper P is directed to the internal tray 109a. (Step S29).

  Next, in step S31, it is determined whether or not the upper exposure flag F1 is “1”. If it is not “1” (NO in step S31), the process proceeds to step S39 described later. On the other hand, if the upper exposure flag F1 is “1” (YES in step S31), the last print is performed, which is stacked on the top of the paper discharge unit 109 after printing the input print job. For the original image I on the recording paper P, the data in the print job is analyzed, and the anti-transmission image (any of the anti-transmission images M1, M2, M3) according to the set confidential document discharge mode is printed. Get the information you need. Then, based on the acquired information, data of an anti-transmission image (any one of the anti-transmission images M1, M2, M3) corresponding to the set confidential document discharge mode is generated, and based on the generated data Processing of the print job for inserting the print of the image for preventing transmission into the final part is performed (step S33).

  Subsequently, based on the processed print job, the transmission preventing image is printed on one recording sheet P in the inkjet head unit 104 (step S35). Subsequently, the dummy paper (any one of the dummy papers D1, D2, and D3) generated by this printing is conveyed toward the internal tray 109a (step S37). Thereafter, the process proceeds to step S39.

  As shown in FIG. 14, in step S39, it is determined whether or not the collective paper discharge flag F5 is “1”. If it is not “1” (NO in step S39), the process proceeds to step S45 described later. To do. On the other hand, if the batch discharge flag F5 is “1” (YES in step S39), the open / close door 111a of the closed internal tray 109a is opened (step S41), and the batch discharge flag F5 is set to “0”. After setting (step S43), the process proceeds to step S45.

  In step S45, both the upper exposure flag F1 and the lower exposure flag F3 are set to “0”. Thereafter, the process proceeds to step S51.

  Further, in step S47, printing of the original image I on the recording paper P by the input print job is performed in the ink-jet head unit 104 by the number specified by the print job, and the printed recording paper P is transferred to the internal tray 109a. (Step S49), the process proceeds to step S51.

  In step S51, it is determined whether or not the power of the inkjet recording apparatus 1 has been cut off. If not cut off (NO in step S51), the process proceeds to step S1, and if cut off (in step S51). YES), a series of processing ends.

  As is apparent from the above description, in the inkjet recording apparatus 1 of the present embodiment, steps S21 and S33 in the flowchart of FIG. 13 are the first and second setting means (reverse distribution image setting) in the claims. The processing corresponds to the means, the complementary color distribution image setting means), and the determination means. Further, in the inkjet recording apparatus 1 of the present embodiment, step S23, step S25, step S35, and step S37 in FIG. 13 are processes corresponding to the dummy paper print execution means in the claims.

  Further, in the inkjet recording apparatus 1 of the present embodiment, the CPU 90 that executes the process of step S7 in the flowchart of FIG. 12 and step S41 in the flowchart of FIG. 14, the opening / closing door 111a of the internal tray 109a, and the opening / closing door 111a. The paper discharge means in the claims is constituted by the transport means (not shown) transported from the internal tray 109a to the paper discharge unit 109 in the open state.

  When the CPU 90 executes the process according to the above-described procedure, each time a print job is generated, the inkjet recording apparatus 1 causes the paper discharge unit 109 to print out the recording paper P on which the document image I is printed by the print job. As shown in FIG. 8A, the original image I is exposed to the outside when discharged and stacked, or on the top recording sheet P discharged face-up as shown in FIG. As shown in (b), dummy papers D1, D2, and D3 on which transmission preventing images M1, M2, and M3 are printed are discharged under the bottom recording paper P that has been face-down discharged.

  Then, the original image I of the uppermost recording paper P discharged face-up or the lowermost recording paper P discharged face-down is masked by the transmission preventing image M1 of the discharged dummy paper D1. Or the overlap-prevented image M2 of the discharged dummy paper D2 is combined with a composite image having a uniform tone without the density of printing density and the density of the printing density, or the discharged dummy paper D3. The image is overlapped with the transmission preventing image M3 having a color distribution complementary to the original image I to be blacked out. As a result, it becomes impossible to recognize the contents of the original image I by seeing it through the dummy papers D1, D2 and D3.

  Therefore, according to the inkjet recording apparatus 1 of the present embodiment, the original image I of the uppermost face-up discharged recording paper P that is exposed to the outside in the paper discharge unit 109, or the user's desk from the paper discharge unit 109. The original image I of the bottom face-down discharged recording paper P, which may be exposed to the outside when being carried around, is discharged to the paper discharge unit 109 together with the recording paper P on which the original image I is printed. The presence of the dummy papers D1, D2, and D3 and their anti-transmission images M1, M2, and M3 can prevent them from being exposed to the public.

  Moreover, according to the inkjet recording apparatus 1 of the present embodiment, the printed recording paper P and the dummy papers D1, D2, and D3 are printed until the printing of all the original images I and the transmission preventing images M1, M2, and M3 is completed. Are discharged and stacked on the internal tray 109a inside the housing, and a dummy sheet is placed above the top recording sheet P and below the bottom recording sheet P of the stacked recording sheets P. The recording paper P and the dummy papers D1, D2, and D3 are collectively discharged to the paper discharge unit 109 outside the housing in a state where D1, D2, and D3 are stacked.

  For this reason, for example, the original image I of the recording paper P that is sequentially face-up discharged to the paper discharge unit 109 until the printing of the number of original images I specified in the print job is completed, and then the dummy paper D1 , D2 and D3 can be prevented from being exposed to the public at the paper discharge unit 109 until they are discharged to the paper discharge unit 109.

  When the blackout mode is set in the confidential document discharge menu, the screen area H1 of the transmission preventing image M3 on the dummy paper D3 is blue and green as described above with reference to FIG. You can print in either color. Therefore, when the data of the transmission preventing image M3 is generated in step S23 or step S35 of FIG. 13, the transmission preventing image in which the color with the larger remaining amount of blue or green is the printing color of the screen region H1 is used. You may comprise so that the data of M3 may be produced | generated.

  Similarly, when the blackout mode is set in the confidential document discharge menu, the screen area H2 of the transmission preventing image M3 on the dummy paper D3 can be printed in either green or red, and the transmission preventing image M3. The screen area H3 can be printed in either red or blue. Therefore, when generating the data of the transmission preventing image M3 in step S23 or step S35 in FIG. 13, the color having the larger remaining amount of green or red is set as the print color of the screen region H2, and the red color is selected. You may comprise so that the data of the permeation | transmission prevention image M3 which makes the color with much ink remaining amount of blue the printing color of the screen area | region H3 may be produced | generated.

  With such a configuration, the ink color with a small remaining amount is actively consumed in printing by the inkjet head unit 104 of the dummy paper D3 in the blackout mode, and the printing of the original image I on the recording paper P is performed only in a specific color. Occurrence of a situation that cannot be executed due to running out of ink can be suppressed as much as possible.

  Further, in the above-described embodiment, in order to facilitate understanding of the description, the screen regions R1, R2, and R3 of the document image I are printed in single colors with red, blue, and green inks, respectively, and their complementary colors are related. When the screen areas H1, H2, and H3 corresponding to the transmission preventing image M3 of the dummy paper D3 are printed in a single color in blue (or green), green (or red), and red (or blue) Explained.

  However, the present invention can also be applied to the case where each of the screen areas R1, R2, and R3 is printed using a plurality of colors of ink instead of a single color. In this case, for example, the screen area H1 of the anti-transmission image M3 is printed with a color distribution in which each color having a complementary color relationship is arranged corresponding to the arrangement of each color in the screen area R1 of the corresponding document image I. Become. The other screen areas H2 and H3 of the anti-transmission image M3 also have a color distribution in which the colors that are complementary to each other are arranged corresponding to the arrangement of the colors in the screen areas R2 and R3 of the corresponding document image I. Each will be printed.

  In this embodiment, an internal tray 109a is provided inside the casing of the inkjet recording apparatus 1, and the recording paper P on which the original image I is printed and the dummy papers D1, D2 on which the transmission preventing images M1, M2, and M3 are printed. , D3 are temporarily discharged to the internal tray 109a, and after all the discharges are completed, they are discharged collectively to the discharge unit 109.

  However, the internal paper discharge unit inside the device that discharges paper (recording paper P) and dummy paper (dummy papers D1, D2, and D3) before batch discharge to the paper discharge unit outside the apparatus is an inkjet recording apparatus 1. It is not always necessary to provide it inside itself.

  For example, as in the image forming system according to the second embodiment of the present invention shown in FIG. 15, a finisher 2 that performs post-processing such as sorting and stapling on the recording paper P after printing is connected to the inkjet recording apparatus 1. In operation, the recording paper P on which the original image I is printed and the dummy papers D1, D2, and D3 on which the transmission preventing images M1, M2, and M3 are printed are temporarily discharged to the internal tray 209a built in the finisher 2. It is also possible to adopt a configuration in which the paper is discharged, and after all the paper is discharged, the paper is discharged collectively to the paper discharge unit 209 outside the casing of the finisher 2.

  Furthermore, the configuration for collectively discharging all the recording paper P and the dummy papers D1, D2, and D3 to the paper discharge units 109 and 209 of the inkjet recording apparatus 1 and the finisher 2 may be omitted.

  Further, in each of the above-described embodiments, the input print job is processed as necessary, and the processed print job is executed so that the transmission preventing images M1, M2, and M3 are recorded on the recording paper in the inkjet head unit 104. P is printed, and the dummy papers D1, D2, and D3 generated thereby are discharged so as to be positioned below the lowermost recording paper P among the recording papers P that are face-down discharged and stacked, Alternatively, a configuration has been described in which the paper is discharged so as to be positioned on the uppermost recording paper P among the recording papers P that have been discharged face-up and stacked.

  However, a separate print job is generated as needed separately from the print job for causing the recording paper P to print the original image I input from the outside, and the image for preventing transmission is obtained by executing this new print job. M1, M2, and M3 are printed on the recording paper P by the inkjet head unit 104, and the dummy papers D1, D2, and D3 generated thereby are recorded at the bottom of the recording paper P that is discharged face down and stacked. The paper is discharged so that it is positioned below the paper P, or the paper is discharged so that it is positioned above the top recording paper P of the stacked recording paper P that is discharged face-up. May be.

  Furthermore, in the first and second embodiments described above, the image forming apparatus (inkjet recording apparatus 1) that prints the document image I and the transmission preventing images M1, M2, and M3 by the inkjet method using the inkjet head unit 104 is taken as an example. I took it and explained it. However, according to the present invention, one or a plurality of printed sheets on which an image has been printed by execution of a print job input from the outside and discharged to the discharge section, and the printed sheets are discharged to the discharge section separately. It is possible to stack paper dummy papers so that the image exposed on the surface of one or more printed papers and exposed to the outside is concealed by a transmission preventing image printed on the dummy papers. For example, the present invention can also be applied to an image forming apparatus that prints an image on a printed sheet or an image for preventing transmission of a dummy sheet by a method other than an inkjet method such as an electrophotographic method.

1 is an explanatory diagram showing a schematic configuration of an ink jet recording apparatus according to a first embodiment of an image forming apparatus according to the present invention. FIG. 2A is an explanatory diagram illustrating a document image printed on a recording sheet in the printer unit of FIG. 1, and FIG. 2B is an explanatory diagram illustrating a recording sheet on which the document image is printed in the printer unit of FIG. It is explanatory drawing which shows schematic structure of the printer part among the inkjet recording devices of FIG. FIG. 2 is a block diagram of an ink jet head unit of the ink jet recording apparatus of FIG. 1. FIG. 4 is a block diagram of an image processing unit of the printer unit of FIG. 3. It is explanatory drawing which shows the operation screen displayed on the display of the inkjet recording device of FIG. It is explanatory drawing which shows the operation screen displayed on the display of the inkjet recording device of FIG. FIG. 8 is an explanatory diagram of a dedicated paper discharge method that can be set by selecting one of the modes on the operation screen of FIG. 7. FIG. 8 is an explanatory diagram of dummy sheets that are discharged in a mode that can be set on the operation screen of FIG. 7. It is explanatory drawing which shows the operation screen displayed on the display of the inkjet recording device of FIG. FIG. 2 is a block diagram illustrating a configuration of a control system of the ink jet recording apparatus of FIG. 1. It is a flowchart which shows the procedure of the process which CPU of the control unit of the inkjet recording device of FIG. 11 performs according to the program stored in ROM. It is a flowchart which shows the procedure of the process which CPU of the control unit of the inkjet recording device of FIG. 11 performs according to the program stored in ROM. It is a flowchart which shows the procedure of the process which CPU of the control unit of the inkjet recording device of FIG. 11 performs according to the program stored in ROM. It is a front view which shows schematic structure of the inkjet recording device which concerns on 2nd Embodiment of the image forming apparatus by this invention.

Explanation of symbols

1 Inkjet recording device (image forming device)
10 control unit 90 CPU (first setting means, second setting means, third setting means, determination means, dummy paper printing execution means, paper discharge means)
102 Printer section (image printing section)
109,209 Paper discharge unit 109a, 209a Internal tray (internal paper discharge unit)
112 Conveyance path (conveyance path)
I Original image (image)
D1, D2, D3 Dummy paper M1, M2, M3 Transmission prevention image P Recording paper (paper)

Claims (10)

The printed paper that has been ejected to the paper ejection unit after printing the image on the paper by executing the print job and the dummy paper that has been ejected to the paper ejection unit separately from the printed paper are stacked to form the print An image concealment method for a printed paper that conceals the image exposed on the surface of the finished paper with the dummy paper,
On the dummy paper,
A first transmission preventing image that covers the entire print area on the paper when the image determined from the print job is printed on the paper in a state where the dummy paper is laminated with the printed paper; and ,
A second anti-transmission material for forming a composite image in which the dummy paper is superimposed on the image of the printed paper in a state of being laminated with the printed paper, and the image cannot be identified in cooperation with the image; image,
At least one of the image for preventing transmission is printed,
An image concealing method for printed paper. The second anti-transmission image is
A reverse distribution image having a print density or print density distribution opposite to the print density or print density distribution on the paper when the image determined from the print job is printed on the paper;
A complementary color distribution image having a color distribution complementary to a color distribution on the paper when the image determined from the print job is printed on the paper;
Including,
The image concealing method for printed paper according to claim 1.   When printing the complementary color distribution image on the dummy paper, the complementary color distribution image can be printed on the dummy paper by single-color printing of two or more ink colors among a plurality of ink colors used for printing the image. 3. The image concealing method for printed paper according to claim 2, wherein the complementary color distribution image is printed on the dummy paper by single color printing of ink color having the largest remaining amount.   By processing the print job and executing the post-processing print job, printing of the image on the paper, printing of the transmission preventing image on the dummy paper, and printing of the dummy after printing of the transmission preventing image are performed. 4. The image concealing method for printed paper according to claim 1, wherein the paper is discharged to the paper discharge unit.   The printed paper and the dummy paper are temporarily discharged and stacked on an internal paper discharge unit, and the stacked printed paper and the dummy paper are collectively discharged to the paper discharge unit. 5. The image concealing method for printed paper according to claim 1, 2, 3 or 4. By stacking the printed paper discharged to the paper discharge unit after printing the image in the image printing unit by executing the print job and the dummy paper discharged to the paper discharge unit separately from the printed paper, In the image forming apparatus for concealing the image exposed on the surface of the printed paper with the dummy paper,
Determining means for determining an image for preventing transmission to be printed on the dummy paper based on the image determined from the print job;
After the image for preventing transmission determined by the determining means is printed by the image printing unit, the images that are exposed to the outside of the printed paper are arranged in the order in which the images are hidden by the image for preventing transmission. Dummy paper printing execution means for causing the image printing unit to print the transmission preventing image on the dummy paper so that the dummy paper is discharged to the paper portion;
The determining means includes
The transmission preventing image is set so as to cover the entire printing area on the paper when the image determined from the print job is printed on the paper in a state where the dummy paper is laminated with the printed paper. First setting means;
The transmission preventing image, wherein the dummy paper is superimposed on the image of the printed paper in a state of being laminated with the printed paper, and forms a composite image in which the image cannot be identified in cooperation with the image. A second setting means for setting
Including at least one of
The dummy paper printing execution unit causes the image printing unit to print the transmission preventing image on the dummy paper set by at least one of the first and second setting units.
An image forming apparatus. The second setting means includes
The reverse distribution image having a print density or print density distribution opposite to the print density or print density distribution on the paper when the image determined from the print job is printed on the paper is prevented from transmitting. Reverse distribution image setting means for setting as an image,
A complementary color distribution that sets a complementary color distribution image having a complementary color distribution to the color distribution on the paper when the image determined from the print job is printed on the paper is set as the transmission preventing image. Image setting means;
Including,
The image forming apparatus according to claim 6.   The complementary color distribution image setting means, when the complementary color distribution image is printable on the dummy paper by single color printing of two or more ink colors among a plurality of ink colors used for printing the image. 8. The image forming apparatus according to claim 7, wherein the complementary color distribution image is set to a single color print of ink color having the largest remaining amount.   The dummy sheet printing execution unit processes the print job, and causes the image printing unit to print the transmission preventing image on the dummy sheet based on the processed print job. Item 9. The image forming apparatus according to Item 6, 7 or 8.   An internal paper discharge unit that is disposed inside the image forming apparatus and that discharges and stacks the dummy paper on which the transmission preventing image is printed by the dummy paper print execution unit and the printed paper; A paper discharge unit that collectively discharges the printed paper and the dummy paper stacked in the paper discharge unit to the paper discharge unit, and the paper discharge unit is provided outside the image forming apparatus. The image forming apparatus according to claim 6, wherein the image forming apparatus is disposed.

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