JP2018017827A - Image formation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect entered information and also prevent handwritten information from being altered while suppressing transparent toner from being wasted.SOLUTION: An image formation apparatus includes: an operation accepting part which accepts a setting operation for a protection region; a sheet feeding part; a conveying part which conveys fed and supplied sheets; and an image formation part including a protection layer forming unit which forms a transparent toner image; a transfer part which transfers the formed toner image to the sheet being conveyed; a fixing part which fixes the toner image; and a control part which allows a sheet feeding part to feed the sheet, the conveying part to convey the sheet, the image forming part to form the transparent toner image covering the protection region, the transfer part to transfer the transparent toner image to the protection region, and the fixing part to fix the transparent toner image.SELECTED DRAWING: Figure 8

Description

  The present invention relates to an image forming apparatus using a transparent toner.

  Some image forming apparatuses such as printers, multifunction machines, copying machines, and facsimile machines print using toner. Here, the toner is not limited to a colored (opaque) toner, and there is a transparent toner.

  Patent Document 1 describes an example of a transparent toner. Patent Document 1 discloses that a white portion where toner is not developed remains as it is, and that the paper remains as it is, and that the entire image is overcoated with a glossy transparent toner after image printing to make the entire image a glossy image, polyester resin It is described that a transparent toner having a binder resin cannot satisfy the fixing property and glossiness, and therefore, the use of a transparent toner for overcoat containing a polyvinyl acetal resin as a binder resin is described (Patent Document 1: Claim 1, paragraphs [0003]-[0007]).

JP 2008-203746 A

  Information such as letters, numbers, and symbols in a document may fade and fade due to rubbing between documents or changes over time. In addition, information on a document may be written using an ink writing instrument with low wear resistance and weather resistance. Examples of documents to be filled in by hand include application forms, application forms, notification forms, request forms, and documents submitted to work or government offices. Information entered with such ink may disappear before the document retention period expires. It is preferable to protect the information described in the document so as not to lose color.

  In addition, for documents that need to be stored for a long period of time or for documents that are not desirable to be tampered with, there may be a warning that it should be written with a writing instrument that does not easily spread or disappear, such as a pole pen. However, even if a cautionary note is attached, the document may be entered with a writing instrument that can be easily tampered with, such as a pencil. Information written with a pencil can be easily rewritten by erasing it with an eraser. There is also a problem that it is necessary to prevent falsification (rewriting) of written information.

  Patent Document 1 describes that the entire surface of a printed paper is overcoated with a transparent toner. However, since the entire surface of the sheet is covered with the transparent toner, a large amount of toner is consumed.

  In view of the above problems, the present invention protects written information and prevents falsification of handwritten information while suppressing wasteful consumption of transparent toner.

  In order to achieve the above object, an image forming apparatus according to a first aspect includes an operation receiving unit, a paper feeding unit, a conveying unit, an image forming unit, a transfer unit, a fixing unit, and a control unit. The operation accepting unit accepts an operation for setting a protection area in the sheet. The paper feeding unit feeds a sheet. The conveyance unit conveys the sheet supplied from the sheet feeding unit. The image forming unit includes a protective layer forming unit that forms a transparent toner image for protecting the surface of the sheet using the transparent toner. The transfer unit transfers the toner image formed by the image forming unit onto the conveyed sheet. The fixing unit heats and pressurizes the toner image transferred to the sheet and fixes the toner image. When printing in the protective printing mode, the control unit feeds a sheet set in the paper feeding unit, transports the sheet to the transport unit, and creates a transparent toner image covering the set protective region. The transparent toner image is formed on the image forming unit, the transparent toner image is transferred to the protection region, and the transparent toner image is fixed on the fixing unit.

  According to the present invention, it is possible to provide an image forming apparatus capable of protecting written information and preventing falsification of handwritten information without wasteful consumption of transparent toner.

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. FIG. 3 is a diagram illustrating an example of an image forming unit and an intermediate transfer unit according to the embodiment. 6 is a flowchart illustrating an example of a flow of registering form data in a multifunction peripheral according to an embodiment. It is a figure which shows an example of the protection printing menu screen which concerns on embodiment. It is a figure which shows an example of the 1st form data registration screen which concerns on embodiment. It is a figure which shows an example of the 2nd form data registration screen which concerns on embodiment. 6 is a flowchart illustrating an example of a processing flow in an automatic form recognition mode installed in a multifunction peripheral according to an embodiment. 6 is a flowchart illustrating an example of a processing flow in a form selection mode installed in the multifunction peripheral according to the embodiment. It is a figure which shows an example of the form selection screen which concerns on embodiment. It is a figure which shows an example of the multifunctional device which concerns on a modification.

  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 that performs calculation and control, and an image processing unit 12 that performs image processing necessary for a job on 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 communicably connected to the document conveying unit 3a and the image reading unit 3b (corresponding to a form receiving unit). 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, 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 the operated operation image among the operation images such as soft keys displayed on the display unit 41. Further, 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 conveys the sheet to the conveyance unit 5b through the image forming unit 5c and the fixing unit 5e to the discharge tray 58 (not shown). The control unit 1 causes the image forming unit 5c to form a toner image that covers the sheet conveyed from the conveyance unit 5b.

  The image forming unit 5c is a unit that forms a toner image using colored toner, and 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, It includes an image forming unit 6C that forms a cyan toner image, an image forming unit 6M that forms a magenta toner image, and a protective layer forming unit 6T that forms a transparent toner image using 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 54, and performs intermediate transfer of the toner image on the intermediate transfer belt 54 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 56 that includes a heater 55 and heats the sheet, and a pressure roller 57 that presses against the heating roller 56. The conveyance unit 5b discharges the printed sheet to the discharge tray 58. 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 13 (corresponding to a form reception unit). The communication unit 13 is an interface for communicating with a computer 200 such as a PC or a server. The communication unit 13 receives from the computer 200 job data including data indicating print contents such as image data and data indicating settings related to printing. The control unit 1 causes the printing unit 5 to perform printing based on the job data.

(Image forming unit 5c and intermediate transfer unit 5d)
Next, an example of the image forming unit 5c and the intermediate transfer unit 5d according to the embodiment will be described with reference to FIGS. FIG. 3 is a diagram illustrating an example of the image forming unit 5c and the intermediate transfer unit 5d according to the embodiment.

  The image forming unit 5c includes four image forming units 6Bk, 6Y, 6C, and 6M that form colored toner images. The image forming unit 5c includes a protective layer forming unit 6T that forms a transparent toner image for protecting the surface of the sheet using transparent toner. The image forming unit 5c includes an exposure device 59 that scans and exposes the photosensitive drum 61 included in each image forming unit and each protective layer forming unit 6T with a laser beam.

  The image forming units 6Bk to 6M and the protective layer forming unit 6T are different in the color of the toner image to be formed, but have the same configuration. there. In the following description, the same members are included in the image forming units 6Bk to 6M and the protective layer forming unit 6T.

  As shown in FIG. 3, each of the image forming units 6Bk to 6M and the protective layer forming unit 6T includes a photosensitive drum 61, a charging device 62, a developing device 63, and a cleaning device 64. The photosensitive drum 61 (image carrier) receives the driving force of the motor 5f (see FIG. 1) and rotates at a predetermined peripheral speed. The charging device 62 charges the surface of the photosensitive drum 61 with a constant potential. The exposure device 59 performs scanning exposure of the photosensitive drum 61 after charging with an optical signal (laser light, illustrated by a broken line in FIG. 2) based on an image signal obtained by color-separating image data. As a result, an electrostatic latent image is formed on the peripheral surface of the photosensitive drum 61.

  The developing device 63 of the image forming unit 6Bk stores black, the developing device 63 of the image forming unit 6Y stores yellow, the developing device 63 of the image forming unit 6C stores cyan, and the developing device 63 of the image forming unit 6M stores magenta toner. The developing device 63 of the protective layer forming unit 6T accommodates transparent toner. Each developing device 63 develops the electrostatic latent image on the corresponding photosensitive drum 61 with toner. The toner image generated by development is transferred to the intermediate transfer belt 54 of the intermediate transfer portion 5d. The toner image superimposed and transferred on the intermediate transfer belt 54 is transferred to the sheet by the secondary transfer roller 510. The cleaning device 64 rubs the surface of the photosensitive drum 61 to remove residual toner.

(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. 4 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. 5 is a diagram illustrating an example of the protected printing menu screen S0 according to the embodiment. FIG. 6 is a diagram illustrating an example of the first form registration screen S1 according to the embodiment. FIG. 7 is a diagram illustrating an example of the second form registration screen S2 according to the embodiment.

  The multi-function device 100 includes a protective layer forming unit 6T. The multifunction peripheral 100 has a print mode in which a specific area to be protected (protected area) of the sheet is covered with a transparent toner image, and information described in the protected area is protected. In the following description, this mode is referred to as a protected printing mode.

  In the protected printing mode, form data D1 that is image data of a document form (format, template, format, format) and a protected area of the form are set and registered in advance. Then, by setting a sheet including the registered form and starting printing in the protection printing 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.

  The flow of registration of the form data D1 will be described with reference to FIGS. Regarding the protected printing mode, a protected printing menu screen S0 is prepared. When a predetermined input is performed on the operation panel 4, the control unit 1 causes the display unit 41 to display the protected printing menu screen S 0. FIG. 5 is a diagram illustrating an example of the protected printing menu screen S0. The protected printing menu screen S0 includes a form registration key K1, a first protected printing execution key K2, and a second protected printing execution key K3. The control unit 1 recognizes a touch on the display position of the form registration key K1 as a form registration start instruction. The start of the flowchart of FIG. 4 is the time when the form registration key K1 is operated.

  First, the multi-function device 100 accepts input of form data D1 (step # 11). The form data D1 is image data of a document or document 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 13. In this case, the communication unit 13 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 13 in the storage unit 2 as form data D1 (step # 12). Based on the form data D1 stored in the storage unit 2, the control unit 1 causes the display unit 41 to display a protection range setting image i1 indicating the contents of the form data D1 (step # 13).

  FIG. 7 shows an example of the first form registration screen S1 when registering a form of a certain application form. By operating a flick operation on the touch panel 42 or a scroll bar i2 arranged on the right side of the screen, it is possible to move a displayed portion of the sheet including the application form. Further, the magnification of the displayed form (sheet) can be enlarged or reduced by a pinch-in / pinch-out operation. In the first form registration screen S1, a protection area can be set in the form. For setting the protection area, a first area setting key K4 and a second area setting key K5 are provided.

  When the first area setting key K4 is operated, the control unit 1 recognizes the area surrounded by tracing (moving the fingertip while touching) as the protection area. When the second area setting key K5 is operated, the control unit 1 recognizes the area including the touch point as the protection area. Here, the control unit 1 recognizes the area surrounded by the ruled line in the form data D1 (protection range 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. FIG. 6 shows an example of a state in which the blank on the right side of the column in which the name characters are written is touched in order to set the name entry column in the protection area.

  Then, the control unit 1 stores in the storage unit 2 the position data D2 indicating the position of the protection area set by the designation of the tracing or column in the form data D1 in association with the form data D1 (step # 14). . When the next key is operated on the first form registration screen S1, the control unit 1 displays the second form registration screen S2 on the display unit 41 (step # 15). The second form registration screen S2 is a screen for performing various settings regarding registration of the form data D1.

  FIG. 7 shows an example of the second form registration screen S2. On the second form registration screen S2, (1) the glossiness of the transparent toner image, (2) the name of the form data D1 to be registered, (3) the necessity of test printing upon completion of registration, and the like can be set. Other items may be set.

  In order to set the glossiness of the transparent toner image, a high glossiness key K7 and a low glossiness key K8 are provided. For the form data D1 for which the high gloss key K7 is selected, the control unit 1 causes a high gloss transparent toner image to be printed. For the form data D1 for which the low glossiness key K8 is selected, the control unit 1 causes a low glossy transparent toner image to be printed. The second form registration screen S2 in FIG. 7 shows a state where high glossiness is selected. Glossiness data D3 indicating the selected glossiness is stored in the storage unit 2 in association with the form data D1 (see FIG. 1).

  The control unit 1 automatically assigns the name of the form data D1. In the example of FIG. 7, an example is shown in which a name is automatically assigned to the form data D1 in a form of “character string of“ form ”+“ serial number of input form data D1 ”. When the change key K9 is operated, the control unit 1 causes the display unit 41 to display a software keyboard (not shown) for inputting characters, symbols, and numbers. The user can attach a desired data name to the form data D1 by operating the software keyboard.

  When the necessary key K10 is operated, the control unit 1 performs test printing of the form data D1 in accordance with the completion of registration. When the unnecessary key K11 is operated, the control unit 1 does not perform test printing. Note that when the completion key K12 arranged on the second form registration screen S2 is operated, the control unit 1 recognizes that all the settings related to the registration of the form data D1 are completed.

  When the completion key K12 is operated in a state where the test printing is necessary, the control unit 1 causes the paper supply unit 5a to supply paper and causes the conveyance unit 5b to convey the sheet (white paper). In addition, the control unit 1 forms a transparent toner image on the image forming unit 5c (protective layer forming unit 6T) based on the registered form data D1, and also forms a toner image of the content (document) of the form in each image forming unit. To form. The controller 1 primarily transfers the transparent toner image and the colored toner image onto the intermediate transfer belt 54, and then collectively transfers the superimposed toner images onto the sheet. The control unit 1 causes the fixing unit 5e to fix the toner on the sheet. As a result, the contents of the registered form are printed, and a sheet in which a portion designated as the protection area is covered with a transparent toner image is printed. By looking at the print result, the user can confirm whether or not the protection area is correctly set.

  When the setting operation on the second form registration screen S2 is received, the control unit 1 stores the setting content in the storage unit 2 (step # 16). When the completion key K12 is operated, the control unit 1 performs test printing in some cases (step # 17). Then, this flow ends (END).

(Form automatic recognition mode)
Next, an automatic form recognition mode installed in the multi-function device 100 according to the embodiment will be described with reference to FIGS. FIG. 8 is a flowchart illustrating an example of a flow of processing in the automatic form recognition mode installed in the multifunction peripheral 100 according to the embodiment.

  The form automatic recognition mode is one of the protected printing modes. In the form automatic recognition mode, the form data corresponding to the sheet set in the sheet feeding unit 5a among the form data D1 registered in the storage unit 2 is read based on the image data obtained by reading the conveyed sheet. In this mode, D1 is automatically recognized. In the automatic form recognition mode, the control unit 1 forms an image of a transparent toner image that covers (overlays) the protection area of the sheet set in the paper feeding unit 5a based on the position data D2 corresponding to the recognized form data D1. It forms in the formation part 5c.

  As illustrated in FIGS. 1 and 2, the multifunction peripheral 100 includes a sheet reading unit 7 for reading a 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 510). 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.

  Here, the user sets in advance a sheet (sheet bundle) to be protected with the transparent toner image. The sheet protected by the transparent toner layer is set in the manual sheet feeding unit 53 so that the sheet reading unit 7 can read the sheet. Note that the sheet to be protected 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. The sheet set for protection is a document in which a form (form) such as an application form, a report, an in-house document, and a form is defined, and is a sheet of the same form as the registered form data D1. The sheet is set so that the description surface of the information to be protected faces upward.

  The start of the flowchart of FIG. 8 is the time when an instruction to execute protected printing in the automatic form recognition mode is given. Specifically, this is the time when the control unit 1 recognizes that the first protected printing execution key K2 has been operated on the protected printing menu screen S0 (see FIG. 5). First, the control unit 1 causes the manual sheet feeding unit 53 and the conveyance unit 5b to start feeding and conveying one set sheet (step # 21). Subsequently, the control unit 1 causes the sheet reading unit 7 to read the conveyed sheet (step # 22).

  Based on the image data obtained by the reading of the sheet reading unit 7, the control unit 1 forms a form corresponding to the sheet set in the manual sheet feeding unit 53 among the form data D1 stored in the storage unit 2. Data D1 is recognized (step # 23). 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.

  For example, the control unit 1 recognizes characters, numbers, and symbols included in the image data, recognizes form data D1 that includes the same characters, numbers, and symbols as the form data D1 corresponding to the set sheet. Also good. 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.

  Then, based on the position data D2 (data indicating the position of the protection area) stored in association with the form data D1, the control unit 1 recognizes the position of the protection area of the set sheet (step # 24). ). Further, the control unit 1 checks whether or not a high gloss level is selected based on the gloss level data D3 stored in the storage unit 2 in association with the form data D1 (step # 25).

  The smoother the surface of the toner after fixing, the higher the gloss. When the toner is sufficiently melted over a period of time passing through the fixing unit 5e, gloss is likely to appear. Therefore, when the high gloss level is selected, the control unit 1 controls the rotation speed of the motor 5f to control the sheet feeding unit 5a, the conveyance unit 5b, the image forming unit 5c, the intermediate transfer unit 5d, and the fixing unit 5e. You may make the rotational speed of each rotary body contained low. That is, the control unit 1 conveys the sheet at the normal speed when the low glossiness is selected, and lowers the sheet conveyance speed than the normal when the high glossiness is selected. In the case of high glossiness, for example, the control unit 1 sets the sheet conveyance speed to ½ of the normal speed.

  In order to sufficiently melt the toner, the control unit 1 may increase the temperature at which the fixing unit 5e heats the toner image when the high gloss level is selected than when the low gloss level is selected. . In other words, the control unit 1 increases the output of the heater 55 when the high gloss level is selected than when the low gloss level is selected. The control unit 1 sets the temperature at which the toner is heated when the low glossiness is selected as the normal fixing temperature (predetermined temperature). On the other hand, at the high glossiness, the control unit 1 makes the temperature for heating the toner higher than the normal fixing temperature. If the temperature is too high, the toner may peel off from the sheet. For example, the temperature is increased by about 10 ° C. to 20 ° C.

  When high glossiness is selected, either the sheet conveyance speed or the toner heating temperature may be changed, or both may be changed. In this description, an example in which both are changed will be described. When the selected gloss level is a high gloss level (Yes in step # 25), the control unit 1 lowers the sheet conveyance speed below the normal conveyance speed and sets the temperature at which the fixing unit 5e heats the toner to normal fixing. The temperature is made higher than the temperature (step # 26). When the selected glossiness is a low glossiness (No in Step # 25), the control unit 1 sets the sheet conveyance speed to the normal conveyance speed, and sets the temperature at which the fixing unit 5e heats the toner to the normal fixing temperature. (Step # 27).

  Subsequently, the control unit 1 determines whether information is written in the protection area (whether or not it is blank) based on the image data obtained by reading by the sheet reading unit 7 (step # 28). . For example, the control unit 1 determines the background color in the image data obtained by reading by the sheet reading unit 7. The control unit 1 determines the pixel value having the largest number of pixels in the image data obtained by reading by the sheet reading unit 7 as the background color. When the sheet is white, the background color is white. The control unit 1 checks the number of pixels having a pixel value different from the background color by a predetermined value or more in the protection area, and determines that information is written in the protection area when the number is equal to or more than a threshold value. For example, when black characters are written on a white background, the control unit 1 determines that information is written in the protection area. When the number is less than the threshold, the control unit 1 determines that no information is entered in the protection area. For example, when the background color is white and there is no information entered and there are only white pixels, the control unit 1 determines that no information is entered in the protection area.

  Further, the control unit 1 determines the presence or absence of a protruding region that is written out of the protected region set based on the image data obtained by reading by the sheet reading unit 7 (step # 29). For example, when there is a line protruding from the inside of the protection area toward the outside of the protection area (when there is a line connected to the protection area), the control unit 1 recognizes the protruding line as a protrusion area. When there is no line protruding from the protection area toward the outside of the protection area, the control unit 1 recognizes that there is no protrusion area.

  Then, the control unit 1 causes the image forming unit 5c to form a transparent toner image that covers the protection area and the protruding area (step # 210). As a result, the area designated as the protection area and the area surrounded by the tracing are covered with the transparent toner image. In addition, the control unit 1 treats a range of a certain distance from each pixel constituting the line protruding from the protection area as the protrusion area. A region surrounding the protruding line is covered with a protective layer formed of a transparent toner image.

  Note that the control unit 1 causes the image forming unit 5c to form a transparent toner image that covers the protected area in which information is written. If the information is not entered, the control unit 1 forms a transparent toner image in the protected area in the image forming unit 5c. (Step # 210). That is, the protected area where no information is written is not 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 512 is provided between the pair of registration rollers 511 provided in front of the secondary transfer roller 510 of the intermediate transfer unit 5d from the manual sheet feeding unit 53 (see FIG. 2). Based on the output of the sheet sensor 512, the control unit 1 recognizes the arrival of the leading edge of the sheet fed from the manual sheet feeding unit 53 at the installation position of the sheet sensor 512. The control unit 1 starts the formation of a transparent toner image in the image forming unit 5c (the protective layer forming unit 6T, 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 512. Let Further, the control unit 1 conveys the sheet and reaches the registration roller pair 511 (see FIG. 2). A registration sensor 513 is provided in the vicinity of the upstream side of the registration roller pair 511 in the sheet conveying direction (see FIG. 2). The controller 1 recognizes the arrival of the leading edge of the sheet at the registration roller pair 511 based on the output of the registration sensor 513. The control unit 1 stops the registration roller pair 511 when the sheet arrives, and rotates the registration roller pair 511 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 # 211). As a result, the sheet is discharged out of the apparatus (discharge tray 58) (step # 212).

  The control unit 1 checks whether or not a sheet remains in the manual sheet feeding unit 53 (step # 213). 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 514 (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 514.

  When a sheet remains in the manual sheet feeding unit 53 (Yes in Step # 213), the control unit 1 causes the manual sheet feeding unit 53 and the conveyance unit 5b to start feeding and conveying the next sheet. Step # 214). Then, the flow returns to step # 29. On the other hand, when no sheet remains in the manual sheet feeder 53 (No in step # 213), 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.

(Form selection mode)
Next, the form selection mode installed in the multifunction peripheral 100 according to the embodiment will be described with reference to FIGS. 1, 2, 9, and 10. FIG. 9 is a flowchart illustrating an example of a processing flow in the form selection mode installed in the multifunction peripheral 100 according to the embodiment. FIG. 10 is a diagram illustrating an example of the form selection screen S4 according to the embodiment.

  The form selection mode is one of the protected printing modes. The form selection mode is a mode in which the user selects form data D1 corresponding to a sheet set in the sheet feeding unit 5a from registered form data D1. In the form selection mode, the control unit 1 displays the transparent toner image covering the protection area of the sheet set in the sheet feeding unit 5a based on the position data D2 corresponding to the selected form data D1. To form. In this form selection mode, the sheet reading unit 7 is not necessary. Therefore, when the sheet reading unit 7 is not provided, the form selection mode is installed in the multifunction peripheral 100, but the automatic form recognition mode is omitted.

  The start of the flowchart of FIG. 9 is the time when an instruction to execute protected printing in the form selection mode is issued. Specifically, this is the time when the control unit 1 recognizes that the second protected printing execution key K3 has been operated on the protected printing menu screen S0 (see FIG. 5). Before starting the flowchart of FIG. 9, the user sets a sheet (sheet bundle) to be protected with a transparent toner image.

  First, the control unit 1 displays the form selection screen S4 on the display unit 41 (step # 31). FIG. 10 shows an example of a form selection screen S4 that displays a list of thumbnail images of each form data D1 (thumbnail display). A form selection key K13 including the name of the form data D1 is attached to each reduced image. The user operates the form selection key K13 corresponding to the set sheet, and the control unit 1 recognizes the selected form data D1 (step # 32). Based on the position data D2 (data indicating the position of the protection area) attached to the selected form data D1, the control unit 1 recognizes the position of the protection area of the set sheet (step # 33).

  The control unit 1 causes the manual sheet feeding unit 53 and the conveyance unit 5b to start feeding and conveying one set sheet (step # 34). Further, the control unit 1 checks whether or not the selected glossiness is a high glossiness based on the glossiness data D3 stored in the storage unit 2 in association with the form data D1 (step # 35).

  When the selected gloss level is a high gloss level (Yes in step # 34), the control unit 1 sets the sheet conveyance speed lower than the normal conveyance speed and sets the temperature at which the fixing unit 5e heats the toner to normal fixing. The temperature is made higher than the temperature (step # 36). When the selected glossiness is a low glossiness (No in step # 34), the control unit 1 sets the sheet conveyance speed to the normal conveyance speed, and sets the temperature at which the fixing unit 5e heats the toner to the normal fixing temperature. (Step # 37). This is the same as the automatic form recognition mode.

  The control unit 1 causes the image forming unit 5c to form a transparent toner image that covers the protection area (step # 38). Subsequently, the control unit 1 causes the intermediate transfer unit 5d to transfer the transparent toner image to the protection area on the sheet, and fixes the transparent toner image to the fixing unit 5e (step # 39). As a result, the sheet is discharged out of the apparatus (discharge tray 58) (step # 310).

  The control unit 1 checks whether or not a sheet remains in the manual sheet feeding unit 53 (step # 311). 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 514 (see FIG. 2). When a sheet remains in the manual sheet feeder 53 (Yes in Step # 311), the control unit 1 feeds and conveys the next set sheet to the manual sheet feeder 53 and the conveyance unit 5b. Start (step # 312). Then, the flow returns to step # 38. On the other hand, when no sheet remains in the manual sheet feeder 53 (No in step # 311), 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.

(Modification)
Next, an example of a modified example of the multifunction peripheral 100 according to the embodiment will be described with reference to FIG. FIG. 11 is a diagram illustrating an example of the multifunction peripheral 100 according to the modification.

  In the above embodiment, an example has been described in which when the high glossiness is selected, the sheet conveyance speed is set to a lower speed than normal, and the fixing unit 5e sets the toner fixing temperature higher than normal. However, as shown in FIG. 11, the glossiness of the transparent toner image may be changed by providing a plurality of protective layer forming units 6T. FIG. 11 shows an example in which the left side of the protective layer forming unit 6T is the first protective layer forming unit 6T1, and the right side is the second protective layer forming unit 6T2.

  The first protective layer forming unit 6T1 forms a transparent toner image using the first transparent toner. The second protective layer forming unit 6T2 forms a transparent toner image using the second transparent toner having a lower gloss than the first transparent toner. The first transparent toner and the second transparent toner have different toner materials and have different gloss after fixing.

  The control unit 1 recognizes the selected glossiness based on the glossiness data D3. When the high gloss level is selected, the control unit 1 causes the image forming unit 5c to form a transparent toner image using the first protective layer forming unit 6T1. When the low gloss level is selected, the control unit 1 causes the image forming unit 5c to form a transparent toner image using the second protective layer forming unit 6T2. Even if the sheet conveyance speed and the toner fixing temperature are not changed from the normal values, the glossiness of the transparent toner image can be made different only by replacing the protective layer forming unit 6T that forms the transparent toner image.

  As described above, the image forming apparatus (multifunction peripheral 100) according to the embodiment includes the operation receiving unit, the paper feeding unit 5a, the transport unit 5b, the image forming unit 5c, the transfer unit, the fixing unit 5e, and the control unit 1. The operation reception unit receives an operation for setting a protection area in the sheet. The sheet feeding unit 5a feeds a sheet. The conveyance unit 5b conveys the sheet supplied from the sheet feeding unit 5a. The image forming unit 5c includes a protective layer forming unit 6T that forms a transparent toner image for protecting the surface of the sheet using transparent toner. The transfer unit transfers the toner image formed by the image forming unit 5c onto the conveyed sheet. The fixing unit 5e heats and presses the toner image transferred to the sheet and fixes the toner image. When printing in the protection printing mode, 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 covering the set protection region. The transparent toner image is formed on the forming unit 5c, and the transfer of the transparent toner image to the protection region is performed on the transfer unit, and the transparent toner image is fixed on the fixing unit 5e.

  Accordingly, by setting an area (column) in which information to be protected such as letters, numbers, symbols, or an area in which information is written by handwriting is set as the protection area, the information to be protected is included in the sheet. Only the described area can be covered with a transparent toner image. By covering with a transparent toner image, it is possible to reduce the influence of friction and contact with air, and to prevent discoloration of information entered in the protection area. Further, since only the protection area is covered with the transparent toner image, wasteful use of the transparent toner can be eliminated as compared with the case where the entire surface of the sheet is covered with the transparent toner. Further, even if information is written with a writing tool that can be easily rewritten, such as a pencil, the written information can be protected with a layer of transparent toner so that it cannot be tampered with.

  The image forming apparatus according to the embodiment includes a form receiving unit (image reading unit 3b, communication unit 13) that receives input of form data D1 that is image data of a form of a sheet to be protected, and form data input to the form receiving unit. D1 and a storage unit 2 for storing position data D2 indicating the position of the protection area set by the operation receiving unit in association with the form data D1, and a conveyance path from the sheet feeding unit 5a to the transfer unit. A sheet reading unit 7 for reading the sheet to be read. The control unit 1 positions the form data D1 corresponding to the sheet set in the sheet feeding unit 5a out of the form data D1 registered in the storage unit 2 based on the image data obtained by the reading of the sheet reading unit 7. Based on the data D2, a transparent toner image is formed on the image forming unit 5c to cover the protection area of the sheet set in the paper feeding unit 5a. Thereby, the control unit 1 automatically recognizes the form data D1 corresponding to the set sheet. There is no need to perform the operation of selecting the form data D1. The position of the protection area covered with the transparent toner image can be accurately recognized, and the protection area can be accurately covered with the transparent toner image.

  Based on the image data obtained by reading by the sheet reading unit 7, the control unit 1 determines whether or not information is written in the protection area of the conveyed sheet, and the protection area in which the information is written is determined. The transparent toner image to be covered is formed on the image forming unit 5c, and the transparent toner image on the protection area not filled in is not formed on the image forming unit 5c. Accordingly, when the information to be protected is not written in the protection area, the protection area is not covered with the transparent toner image. Therefore, useless use of transparent toner can be eliminated.

  Based on the image data obtained by the reading of the sheet reading unit 7, the control unit 1 recognizes the protruding region that has been written out from the protection region, and causes the image forming unit 5c to form a transparent toner image that covers the protruding region. Thereby, even if a part of the handwritten characters, numbers, and symbols protrudes from the protection area, the protruding part is also covered with the protective layer of the transparent toner image. Therefore, the entire entered information can be protected.

  The form receiving unit (image reading unit 3b, communication unit 13) receives input of form data D1 that is image data of the form of the sheet to be protected. The storage unit 2 stores the form data D1 input to the form reception unit and the position data D2 indicating the position of the protection area set by the operation reception unit in association with the form data D1. The operation reception unit (operation panel 4) receives selection of the form data D1 corresponding to the sheet set in the paper supply unit 5a. Based on the position data D2 corresponding to the selected form data D1, the control unit 1 recognizes the protection area of the sheet set on the sheet feeding unit 5a, and outputs a transparent toner image covering the recognized protection area to the image forming unit. 5c is formed (form selection mode). Thereby, based on a user's selection, the control part 1 can recognize the form data D1 corresponding to the set sheet | seat. Therefore, the control unit 1 can accurately recognize the position of the protection area covered with the transparent toner image and accurately cover the protection area with the transparent toner image.

  The operation accepting unit accepts the setting of the glossiness of the transparent toner image. The controller 1 may lower the sheet conveyance speed as the set glossiness is higher. Thereby, the higher the set glossiness is, the slower the sheet can pass through the fixing unit 5e. That is, the amount of heat applied to the transparent toner can be increased or decreased according to the set glossiness. Accordingly, the smoothness of the surface of the transparent toner image can be adjusted according to the set glossiness.

  The controller 1 may increase the temperature at which the fixing unit 5e heats the toner image as the set glossiness is higher. Thereby, the amount of heat applied to the transparent toner can be increased or decreased according to the set glossiness. Accordingly, the smoothness of the surface of the transparent toner image can be adjusted according to the set glossiness.

  Further, as in the modification example, the image forming unit 5c has the first protective layer forming unit 6T1 that forms a transparent toner image using the first transparent toner as the protective layer forming unit 6T, and the first transparent toner is more glossy. A second protective layer forming unit 6T2 that forms a transparent toner image using the second transparent toner having a low degree may be included. When the operation accepting unit accepts the selection of high glossiness, the control unit 1 causes the transparent toner image to be formed on the image forming unit 5c using the first protective layer forming unit 6T1, and the operation accepting unit selects the low glossiness. Is received, the transparent toner image is formed on the image forming portion 5c using the second protective layer forming unit 6T2. As a result, the user can form a transparent toner image having a desired glossiness.

  The image forming unit 5c includes an image forming unit that forms a toner image using colored toner. The control unit 1 causes the image forming unit to form a toner image based on the form data D1 stored in the storage unit 2. A registered form (form data D1) can be printed by one image forming apparatus, and the protected area of the filled sheet can be covered with a transparent toner image.

  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.

  The present invention is applicable to an image forming apparatus that performs printing using a transparent toner.

DESCRIPTION OF SYMBOLS 100 MFP (image forming apparatus) 1 Control part 13 Communication part (form reception part) 2 Storage part 3b Image reading part (form reception part) 4 Operation panel (operation reception part)
5a Paper feeding unit 5b Conveying unit 5c Image forming unit 5d Intermediate transfer unit (transfer unit)
5e fixing unit 53 manual sheet feeding unit 6T protective layer forming unit 6T1 first protective layer forming unit 6T2 second protective layer forming unit 6Bk image forming unit 6Y image forming unit 6C image forming unit 6M image forming unit 7 sheet reading unit D1 form data D2 Position data

Claims (9)

An operation accepting unit for accepting an operation for setting a protection area of the sheet;
A paper feeder for feeding sheets;
A transport unit configured to transport a sheet supplied from the paper feed unit;
An image forming unit including a protective layer forming unit for forming a transparent toner image for protecting the surface of the sheet using the transparent toner;
A transfer unit that transfers the toner image formed by the image forming unit to a conveyed sheet;
A fixing unit for fixing the toner image transferred to the sheet by heating and pressing; and
When printing in the protection printing mode, the sheet set in the sheet feeding unit is fed, the sheet is conveyed to the conveyance unit, and a transparent toner image covering the set protection area is transferred to the image forming unit. An image forming apparatus, comprising: a control unit configured to cause the transfer unit to transfer the transparent toner image to the protection region, and to fix the transparent toner image to the fixing unit. A form receiving unit that receives input of form data that is image data of a form of a sheet to be protected, the form data input to the form receiving unit, and the protection set in the operation receiving unit in association with the form data A storage unit for storing position data indicating the position of the area;
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;
The control unit is configured to store the form data corresponding to a sheet set in the sheet feeding unit among the form data registered in the storage unit based on image data obtained by reading the sheet reading unit. The image forming apparatus according to claim 1, wherein the image forming unit forms a transparent toner image that covers the protection area of the sheet set in the sheet feeding unit based on position data.   The control unit determines whether information is written in the protection area of the conveyed sheet based on the image data obtained by the reading of the sheet reading unit, and the protection in which the information is written 3. The image forming apparatus according to claim 2, wherein a transparent toner image covering an area is formed on the image forming unit, and a transparent toner image on the protection area that is not filled in is not formed on the image forming unit.   The control unit recognizes a protruding region that has been written out from the protection region based on image data obtained by reading the sheet reading unit, and causes the image forming unit to form a transparent toner image that covers the protruding region. The image forming apparatus according to claim 2, wherein the image forming apparatus is an image forming apparatus. A form receiving unit that receives input of form data that is image data of a form of a sheet to be protected, the form data input to the form receiving unit, and the protection set in the operation receiving unit in association with the form data A storage unit for storing position data indicating the position of the area,
The operation accepting unit accepts selection of the form data corresponding to a sheet set in the paper feeding unit,
The control unit recognizes the protection area of the sheet set in the sheet feeding unit based on the position data corresponding to the selected form data, and displays the transparent toner image covering the recognized protection area. The image forming apparatus according to claim 1, wherein the image forming apparatus is formed in an image forming unit. The operation accepting unit accepts the setting of the glossiness of the transparent toner image,
The image forming apparatus according to claim 1, wherein the control unit decreases the sheet conveyance speed as the set glossiness is higher. The operation accepting unit accepts the setting of the glossiness of the transparent toner image,
The image forming apparatus according to claim 1, wherein the controller sets a temperature at which the fixing unit heats the toner image as the set glossiness is higher. The operation reception unit receives selection of glossiness of the transparent toner image,
The image forming unit uses, as the protective layer forming unit, a first protective layer forming unit that forms a transparent toner image using the first transparent toner, and a second transparent toner having a glossiness lower than that of the first transparent toner. A second protective layer forming unit for forming a transparent toner image
The controller causes the image forming unit to form a transparent toner image using the first protective layer forming unit when the operation receiving unit receives a selection of high glossiness, and the operation receiving unit has a low glossiness. 6. The image forming apparatus according to claim 1, wherein when the selection is received, a transparent toner image is formed on the image forming unit using the second protective layer forming unit. The image forming unit includes an image forming unit that forms a toner image using colored toner,
The image forming apparatus according to claim 2, wherein the control unit causes the image forming unit to form a toner image based on the form data stored in the storage unit.

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