Image-forming device and image-forming method

Abstract

To appropriately control density of an adhesive image.SOLUTION: An image-forming device comprises: image-forming means for forming an image on a sheet on the basis of first image data; and control means for generating the first image data and outputting it to the image-forming means. The control means determines density of an adhesive image on the basis of types of sheets when forming an image including the adhesive image used as an adhesive on the sheets in response to reception of a print job for forming the image on the multiple sheets and allowing them to adhere mutually.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus and an image forming system including the image forming apparatus and a processing device. [Background technology]

[0002] An image forming system is in use that includes an image forming apparatus that forms an image on a sheet and a processing apparatus that creates a booklet by adhering multiple sheets on which images have been formed by the image forming apparatus. Patent Document 1 discloses a configuration in which sheets are adhered to each other by forming an adhesive image on the sheets using toner used as an adhesive. According to Patent Document 1, in order to ensure adhesive strength between the sheets, the number of sheets to be adhered at one time is controlled depending on the type of sheet. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-215230 Summary of the Invention [Problem to be solved by the invention]

[0004] The adhesive strength between sheets increases with the amount of adhesive applied to the sheets, i.e., the density of the adhesive image. However, if the density of the adhesive image is made higher than necessary, the toner used as adhesive will be wasted. On the other hand, if the density of the adhesive image is made too low, the necessary adhesive strength cannot be secured.

[0005] The present invention provides a technique for appropriately controlling the density of an adhesion image. [Means for solving the problem]

[0006] According to one aspect of the present invention, an image forming device includes an image forming means that forms an image on a sheet based on first image data, and a control means that generates the first image data and outputs it to the image forming means, and in response to receiving a print job that forms images on multiple sheets and adheres them to each other, when the control means forms the image on the sheet, including an adhesive image to be used as an adhesive, the control means determines the density of the adhesive image based on the type of the sheet. [Effects of the Invention]

[0007] According to the present invention, the density of the adhesion image can be appropriately controlled. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic block diagram of an image forming system according to some embodiments. [Figure 2] 10A-10C illustrate examples of adhesive images, according to some embodiments. [Figure 3] 1 is an illustration of a bonding process, according to some embodiments. [Figure 4] FIG. 1 is a control configuration diagram of an image forming system according to some embodiments. [Figure 5] 1A and 1B are diagrams illustrating the configuration of a type detection sensor and an example of sheet type detection according to some embodiments. [Figure 6] 10A and 10B illustrate examples of determination information, according to some embodiments. [Figure 7] 1 is a flowchart of an imaging process according to one embodiment. [Figure 8] 4 is a timing diagram of an image forming process according to one embodiment. [Figure 9] 1 is a flowchart of an imaging process according to one embodiment. [Figure 10] 1 is a flowchart of an imaging process according to one embodiment. [Figure 11] FIG. 1 is a control configuration diagram of an image forming system according to some embodiments. [Figure 12] 10A and 10B are diagrams showing examples of a user image area and an adhesive image area. [Figure 13] 1 is a flowchart of an imaging process according to one embodiment. [Figure 14] 4 is a timing diagram of an image forming process according to one embodiment. [Figure 15] 1 is a flowchart of an imaging process according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0010] First Embodiment FIG. 1 is a diagram illustrating a schematic configuration example of an image forming system according to this embodiment. The image forming system includes an image forming apparatus 1, an intermediate conveying unit 200, and a processing device 300. The image forming apparatus 1 includes four process units 7n, 7y, 7m, and 7c. The process units 7y, 7m, and 7c contain yellow, magenta, and cyan toner, respectively, and form yellow, magenta, and cyan toner images on the intermediate transfer belt 3. The process unit 7n contains toner used as a powder adhesive and forms a toner image using the toner on the intermediate transfer belt 3. The toner used as the powder adhesive may be of any color or transparent. In the following description, when distinguishing between images formed by the process unit 7n and images formed by the process units 7y, 7m, and 7c, the image formed by the process unit 7n will be referred to as an adhesive image, and the image formed by the process units 7y, 7m, and 7c will be referred to as a user image. Furthermore, the adhesive image and the user image will be collectively referred to as a "toner image" or simply as an "image."

[0011] In this embodiment, the process unit 7n is used only for forming adhesive images. However, for example, by storing black toner that can also be used as an adhesive in the process unit 7n, the process unit 7n can also be used for forming user images.

[0012] Because the process units 7n, 7y, 7m, and 7c have similar configurations, the following description will focus on the configuration of process unit 7n. During image formation, the photoconductor 73 rotates clockwise in the figure. The charging roller 71 charges the surface of the photoconductor 73 to a uniform potential. The exposure unit 2 scans and exposes the rotating photoconductor 73 line by line in the main scanning direction based on image data, forming an electrostatic latent image on the photoconductor 73. The main scanning direction is the direction in which the exposure unit 2 moves light based on image data on the photoconductor 73, and corresponds to the direction of the rotation axis of the photoconductor 73. The development unit 72 develops the electrostatic latent image formed on the photoconductor 73 with toner, forming a toner image on the photoconductor 73. The primary transfer roller 74 outputs a primary transfer voltage to transfer the toner image on the photoconductor 73 to the intermediate transfer belt 3, which rotates counterclockwise in the figure. Colors different from yellow, magenta, and cyan are reproduced by overlapping the toner images formed on the photoconductors 73 of process units 7y, 7m, and 7c and transferring them to the intermediate transfer belt 3. In this embodiment, black toner is not used, so the color black is reproduced by overlapping yellow, magenta, and cyan toners. However, as described above, process unit 7n can also be used to form a black toner image. The toner image transferred to the intermediate transfer belt 3 is transported to a position facing the secondary transfer roller 5 by the rotation of the intermediate transfer belt 3.

[0013] The secondary transfer roller 5 outputs a secondary transfer voltage to transfer the toner image on the intermediate transfer belt 3 to the sheet S transported from the cassette 8 or tray 20. The roller 81 transports the sheet S, which has been fed from the cassette 8 or tray 20 to the transport path of the image forming apparatus 1, toward the registration roller 9 located downstream. The registration roller 9 adjusts the timing so that the toner image on the intermediate transfer belt 3 is transferred to the sheet S, and sends the sheet S to a position facing the secondary transfer roller 5. The fixing unit 6 fixes the toner image to the sheet S by applying heat and pressure to the sheet S to which the toner image has been transferred. When an image is formed on only one side (first side) of the sheet S, the sheet S with the fixed toner image is guided by a guide 33 to a transport path provided with a roller 34. The roller 34 then transports the sheet S toward the intermediate transport unit 200. The intermediate transport unit 200 transports the sheet S to the processing device 300.

[0014] When forming images on both sides of a sheet S, after the toner image on the first side is fixed, the sheet S is guided by a guide 33 to a conveying path provided with rollers 35. The rotation direction of rollers 35 is reversed when the trailing edge of the sheet S reaches rollers 35. Thus, the sheet S is conveyed again via a double-sided conveying path 36 to a position facing secondary transfer roller 5, and the toner image is transferred onto its second side. The toner image on the sheet S with the toner image transferred onto its second side is fixed by a fixing unit 6. Thereafter, the sheet S is guided by a guide 33 to a conveying path provided with rollers 34, and is conveyed to a processing device 300 via an intermediate conveying unit 200.

[0015] The process units 7n, 7y, 7m, and 7c, the exposure unit 2, the intermediate transfer belt 3, the secondary transfer roller 5, and the fixing unit 6 constitute an image forming unit that forms an image on a sheet. The image forming apparatus 1 is not limited to forming an image on a sheet via the intermediate transfer belt 3, but may also form an image on a sheet without the intermediate transfer belt 3. The image forming apparatus 1 is not limited to forming a color image, but may also form a monochrome image. In this case, the image forming apparatus 1 has a process unit for forming an adhesive image and a process unit for forming a user image. If the toner used to form the user image and the adhesive image is the same, the image forming apparatus 1 may be provided with only one process unit. The type detection sensor 10 detects the characteristics of the sheet S upstream of the registration roller 9. In this embodiment, the characteristics of the sheet S are represented by the basis weight and surface properties of the sheet S.

[0016] The sheet S conveyed from the intermediate conveying unit 200 to the processing device 300 is conveyed downstream by the entrance rollers 21. When the sheet S is not subjected to adhesive processing, the sheet S is discharged onto the upper tray 25 by the pre-buffer rollers 22 and the reversing rollers 24. On the other hand, when the sheet S is subjected to adhesive processing, the rotation direction of the reversing rollers 24 is reversed after the trailing edge of the sheet S passes the guide 23, thereby conveying the sheet S toward the processing device 42. At this time, the guide 23 is set to a state in which the sheet S is guided toward the processing device 42.

[0017] The sheets S transported to the processing section 42 are abutted against a vertical alignment reference plate 39 of the processing section 42 by rollers 40 provided in the processing section 42, thereby performing an alignment process for one or more sheets stacked in the processing section 42. The processing section 42 performs a bonding process to create a booklet every time a predetermined number of sheets are newly transported to the processing section 42. The created booklet is pushed by the vertical alignment reference plate 39 in the direction of the bundle discharge rollers 38, and is discharged onto the lower tray 37 by the bundle discharge rollers 38.

[0018] 2(A) and 2(B) show examples of adhesive images Tk. In FIGS. 2(A) and 2(B), "first side" refers to the sheet side on which an image is first formed in double-sided image formation, and "second side" refers to a side different from the first side. As shown in FIG. 2(A), by forming the adhesive image Tk on the edge of the long side of the sheet S, a long-length booklet can be produced by the adhesive process in the processing device 300. Also, as shown in FIG. 2(B), by forming the adhesive image Tk on a portion of the edge of the long side of the sheet S, a corner-stitched booklet can be produced by the adhesive process in the processing device 300.

[0019] Note that the adhesive image Tk is formed only on the surface facing the other sheets S when the sheets are stacked in the processing section 42. Therefore, for the sheets S at both ends of the booklet, the adhesive image Tk is formed on only one surface. In addition, in this embodiment, when the sheets are stacked in the processing section 42, the adhesive image Tk is formed on both the upper surface of the first sheet and the lower surface of the second sheet above the first sheet. However, a configuration in which the adhesive image Tk is formed on only one of the upper surface of the first sheet or the lower surface of the second sheet may also be used. Information indicating multiple patterns of the adhesive image Tk shown in Figures 2(A) and 2(B) is stored in advance in the image forming apparatus 1.

[0020] Next, the bonding process in the processing unit 42 will be described. FIGS. 3A and 3B are cross-sectional views of the processing unit 42, viewed from the longitudinal alignment reference plate 39 in FIG. 1 in a direction parallel to the conveyance direction of the sheet S. A ceramic heater 501 incorporating a heating element is supported by a resin heater support 503 and heats an aluminum heating plate 502. The temperature of the ceramic heater 501 is controlled based on a temperature detected by a temperature sensor (not shown). The heating plate 502 also has a pressure unit A. A pressure lever 504 presses the heater support 503, the ceramic heater 501, and the heating plate 502 downward in FIG. 3, i.e., in the direction in which the sheets S are stacked, via a rigid metal stay 505. As a result, the sheets S stacked in the processing unit 42 are heated and pressurized by the heating plate 502. A pressure plate 506 is provided on the opposite side of the sheet S from the heating plate 502 to receive the pressure applied by the heating plate 502. The pressure plate 506 is made of, for example, silicone rubber.

[0021] FIG. 3(A) shows a state in which five sheets S1-1 to S1-5 are stacked in the processing unit 42. As shown in FIG. 3(A), an adhesive image Tk is formed in an area that is heated and pressed by the heating plate 502. In the state shown in FIG. 3(A), the adhesive image Tk is melted and an adhesive process is performed by heating and pressing the five sheets S with the heating plate 502. FIG. 3(B) shows a state in which five new sheets S2-1 to S2-5 are stacked on top of the sheets S1-1 to S1-5 that have been subjected to the adhesive process. In the state shown in FIG. 3(B), the stacked sheets S are heated and pressed by the heating plate 502, and ten sheets S are adhered together.

[0022] 4 shows an example of a schematic hardware configuration of an image forming system. The image forming apparatus 1 has a video controller 110 and an engine controller 100, and the processing device 300 has a finisher control unit 400. The video controller 110 and the engine controller 100 configure the control unit of the image forming apparatus 1. The video controller 110, the engine controller 100, and the finisher control unit 400 are connected to each other and cooperate to control the operation of the image forming system.

[0023] The video controller 110 has a central processing unit (CPU) 111 and a memory 112. The CPU 111 reads and executes programs stored in the memory 112 to perform overall control of the image forming apparatus 1. The memory 112 includes a non-volatile storage medium such as a read-only memory (ROM) and a volatile storage medium such as a random access memory (RAM), and serves as a storage location for programs and data as well as a workspace for the CPU 111 when executing the programs. The memory 112 is an example of a non-transitory computer-readable storage medium that stores programs.

[0024] The video controller 110 is configured to be able to communicate with an external device 600, such as a personal computer or a portable information device, and receives commands to execute a print job from the external device 600. In response to receiving a print job from the external device 600, the CPU 111 causes the engine controller 100 to form an image based on the print job. The CPU 111 then generates image data to be output to the exposure unit 2 based on image information received along with the print job. The image data is used by the exposure unit 2 to form an electrostatic latent image on the photoconductor 73, and may be in the form of, for example, a pulse-width modulation (PWM) signal. If the print job specifies that adhesion processing should be performed by the processing device 300, the CPU 111 generates image data so that not only the user image indicated by the image information received along with the print job but also the adhesive image Tk is formed. As described above, information indicating multiple patterns of the adhesive image Tk is pre-stored in, for example, the memory 112, and the pattern of the adhesive image Tk to be formed is specified by the print job.

[0025] The video controller 110 is also connected to an operation display unit 120, which is a user interface of the image forming system. The operation display unit 120 includes a display device such as a liquid crystal panel that presents information to the user, and an input device such as physical buttons and a touch panel function unit of the liquid crystal panel that accepts input operations by the user. The CPU 111 communicates with the operation display unit 120 to control the display content of the display device and receive information input via the input device.

[0026] The engine controller 100 has a CPU 101 and a memory 102. The CPU 101 performs necessary control by reading and executing programs stored in the memory 102. The memory 102 includes a non-volatile storage medium and a volatile storage medium, and serves as a storage location for programs and data as well as a workspace when the CPU 101 executes the programs. The memory 102 is an example of a non-transitory computer-readable storage medium that stores programs.

[0027] When an image formation command is received from the video controller 110, the CPU 101 controls the components of the image forming apparatus 1 described in FIG. 1 to form an image on the sheet S. FIG. 4 shows only the exposure unit 2 and the type detection sensor 10 described in FIG. 1, and omits other components. As shown in FIG. 4, the engine controller 100 controls the motor M and the clutch CL, which are omitted from FIG. 1. The motor M is a drive source for the roller 81 and the registration roller 9. The clutch CL is set to a transmission state in which the driving force of the motor M is transmitted to the registration roller 9, or a non-transmission state in which the driving force of the motor M is not transmitted to the registration roller 9. The CPU 101 can control the rotation of the registration roller 9 by controlling the state of the clutch CL. The CPU 101 also acquires the detection result of the type detection sensor 10 to determine the type of the sheet S.

[0028] The finisher control unit 400 has a CPU 401 and a memory 402. The CPU 401 reads and executes programs stored in the memory 402, and performs overall control of the processing device 300. The memory 402 includes a non-volatile storage medium and a volatile storage medium, and serves as a storage location for programs and data, as well as a workspace when the CPU 401 executes the programs. The memory 402 is an example of a non-transitory computer-readable storage medium that stores programs.

[0029] As described above, the functions of the video controller 110, the engine controller 100, and the finisher control unit 400 can be implemented in software by causing each CPU to execute an appropriate program. However, some or all of the functions of the video controller 110, the engine controller 100, and the finisher control unit 400 can also be implemented in hardware using an application specific integrated circuit (ASIC) or the like. Furthermore, some or all of the functions controlled by the engine controller 100 can also be performed by the video controller 110. Alternatively, some or all of the functions controlled by the video controller 110 can also be performed by the engine controller 100.

[0030] FIG. 5A shows an example of the configuration of a type detection sensor 10. The type detection sensor 10 includes a basis weight detection unit 11 for detecting the basis weight of the sheet S and a surface property detection unit 14 for detecting the surface property of the sheet S. The basis weight detection unit 11 includes a transmission unit 12 for transmitting ultrasonic waves and a reception unit 13 for receiving the ultrasonic waves. The reception unit 13 receives the ultrasonic waves transmitted by the transmission unit 12 and outputs a voltage corresponding to the level (sound pressure) of the received ultrasonic waves to the CPU 101. The CPU 101 acquires a first level of the ultrasonic waves received by the reception unit 13 when there is no sheet S between the transmission unit 12 and the reception unit 13, and a second level of the ultrasonic waves received by the reception unit 13 when there is a sheet S between the transmission unit 12 and the reception unit 13. The CPU 101 can determine the basis weight of the sheet S based on the ratio of the second level to the first level (transmittance). Note that the lower the transmittance, the greater the basis weight.

[0031] The surface property detection unit 14 has an LED 15 as a light source, a condenser lens 16, and a line sensor 17. The LED 15 is a light source that irradiates the surface of the sheet S with light. The condenser lens 16 is an optical system that guides the light reflected from the sheet S to the line sensor 17. When a highly directional LED is used, the condenser lens 16 can be omitted. The line sensor 17 is an imaging element in which multiple light receiving elements are arranged in a row in a direction perpendicular to the conveyance direction of the sheet S, and each light receiving element measures the light intensity of the light reflected from the sheet S.

[0032] The surface texture is determined by the degree of unevenness (the magnitude of the difference in shading in the captured image). That is, the surface image of the sheet S is acquired by repeatedly measuring the light receiving intensity of each pixel of the line sensor 17 while the sheet S is being conveyed. The CPU 101 determines the degree of unevenness of the sheet S based on the difference in shading in the acquired surface image, and judges the surface texture of the sheet S.

[0033] The CPU 101 determines the type of the sheet S based on the basis weight (transmittance) and the unevenness. FIG. 5B shows an example of the relationship between the combination of transmittance and unevenness and the sheet type. Information showing the correspondence between the detection result of the type detection sensor 10 and the sheet type, as shown in FIG. 5B, is stored in advance in the memory 102. According to FIG. 5B, when the transmittance is smaller than threshold A and the unevenness is smaller than threshold B, the type is determined to be "gloss paper." When the transmittance is smaller than threshold A and the unevenness is equal to or greater than threshold B, the type is determined to be "thick paper." When the transmittance is equal to or greater than threshold A and less than threshold C and the unevenness is smaller than threshold D, the type is determined to be "smooth paper." When the transmittance is equal to or greater than threshold A and less than threshold C and the unevenness is equal to or greater than threshold D, the type is determined to be "plain paper." When the transmittance is equal to or greater than threshold A and less than threshold C and the unevenness is equal to or greater than threshold D, the type is determined to be "plain paper." When the transmittance is equal to or greater than threshold A and less than threshold C and the unevenness is equal to or greater than threshold D, the type is determined to be "thin paper."

[0034] The CPU 101 notifies the CPU 111 of the video controller 110 of the determined type of sheet S. Here, sheets S with relatively large unevenness, such as cardboard or plain paper, are prone to uneven toner application due to the unevenness of the surface. When uneven toner application occurs, the adhesiveness of the adhesive image Tk decreases. Therefore, for sheets S with relatively large unevenness, the amount of toner application in the adhesive image Tk must be increased. On the other hand, for sheets S with small unevenness, such as glossy paper or smooth paper, adhesiveness can be ensured even with a reduced amount of toner application in the adhesive image Tk. Furthermore, for sheets S with high basis weight (low transmittance), such as cardboard or glossy paper, the high stiffness of the sheets makes the adhesive portions between sheets prone to peeling. Therefore, for sheets S with high basis weight, the amount of toner application in the adhesive image Tk must be increased to ensure adhesiveness.

[0035] Therefore, in this embodiment, the CPU 111 of the video controller 110 determines the toner amount of the adhesive image Tk, i.e., the image density of the adhesive image Tk, depending on the type of sheet S. FIG. 6 shows an example of determination information stored in the memory 112 of the video controller 110. The determination information is information indicating the correspondence between the sheet type and the image density of the adhesive image Tk. In FIG. 6, the maximum density of the image formed on the sheet S is set to 100%. According to FIG. 6, for example, an adhesive image Tk with a density of 90% is formed on plain paper.

[0036] 7 is a flowchart of the process executed by the image forming apparatus 1 when the image forming apparatus 1 executes a print job involving booklet creation in the processing apparatus 300. The image forming apparatus 1 is configured to be able to turn on and off the automatic setting mode. When the automatic setting mode is on, the engine controller 100 determines the sheet type using the type detection sensor 10, and the video controller 110 determines the density of the adhesive image Tk based on the sheet type determined by the engine controller 100. On the other hand, when the automatic setting mode is off, the sheet type is set by the user, and the engine controller 100 determines the density of the adhesive image Tk based on the sheet type set by the user.

[0037] In S10, the video controller 110 determines whether the automatic setting mode is set. If the automatic setting mode is not set (if the automatic setting mode is off), the video controller determines the density of the adhesive image Tk based on the set type set by the user as the type of the sheet S in S16. On the other hand, if the automatic setting mode is set (if the automatic setting mode is on), the engine controller 100 determines the type of the sheet S using the type detection sensor 10 when the sheet S reaches the detection position of the type detection sensor 10. Then, in S11, the engine controller 100 notifies the video controller 110 of the type of the sheet S. In S12, the video controller 110 determines the density of the adhesive image Tk based on the sheet type (determined type) determined by the engine controller 100.

[0038] In S13, the video controller 110 generates image data to be sent to the exposure unit 2. When an adhesive image Tk is formed on the first side of the sheet S, the image data is data for forming both the adhesive image Tk and a user image based on an image signal received in the print job on the sheet S, and the density of the adhesive image Tk is the density determined in S12 or S16. In S14, the engine controller 100 notifies the video controller 110 of the timing for sending the image data to the exposure unit 2 and controls the light emission intensity of the exposure unit 2 to form an image on the first side of the sheet S. Note that, although not shown in FIG. 7 for simplicity, when an adhesive image Tk is formed on a second side different from the first side of the sheet S, the density of the adhesive image Tk formed on the second side is also the density determined in S12 or S16. The image forming apparatus 1 determines in S15 whether image formation on all sheets S specified in the print job has been completed. If not completed, the process repeats from S10 until completion.

[0039] 8 shows a timing chart when the image forming apparatus 1 executes a print job involving booklet production in the processing apparatus 300. Note that Fig. 8 is a chart showing the period from when images are formed on both sides of the first sheet S until the sheet is transported to the processing apparatus 300, and it is assumed that the image forming apparatus 1 is set to the automatic setting mode.

[0040] When the video controller 110 receives the print job at time t0, it issues a print instruction to the engine controller 100. In response to the print instruction, the engine controller 100 starts preparatory operations for image formation, such as starting the driving of rotating members such as the photosensitive member 73 and starting the heating of the fixing unit 6. The engine controller 100 also starts feeding the sheet S.

[0041] At time t1, when the sheet S reaches the detection position of the type detection sensor 10, the engine controller 100 causes the type detection sensor 10 to measure the sheet S. When the engine controller 100 acquires the measurement result from the type detection sensor 10 at time t3, it determines the type of the sheet S and notifies the video controller 110 of the type of the sheet S at time t4. The leading edge of the sheet S reaches the position of the registration rollers 9 at time t2, and the engine controller 100 stops conveying the sheet S at this position.

[0042] When the video controller 110 is notified of the sheet type at time t4, it determines the density of the adhesive image Tk based on the sheet type and generates image data for image formation on the first surface of the sheet S. When the generation of the image data is completed at time t5, the video controller 110 notifies the engine controller 100 of the completion of the generation of the image data.

[0043] When the engine controller 100 receives a notification from the video controller 110 that the generation of image data has been completed, it notifies the video controller 110 of the timing to send the image data to the exposure unit 2. In response, the video controller 110 sends the image data to the exposure unit 2. The engine controller 100 also controls the members shown in FIG. 1 so that an image is formed on the sheet S based on the image data sent by the video controller 110 to the exposure unit 2. According to FIG. 8, the registration roller 9 resumes conveying the sheet S at time t6, and sends the sheet S toward the position facing the secondary transfer roller 5.

[0044] When image formation on the first side of the sheet S is completed at time t8, the video controller 110 generates image data for image formation on the second side of the sheet S. When generation of the image data is completed at time t9, the video controller 110 notifies the engine controller 100 of the completion of generation of the image data.

[0045] When the engine controller 100 receives a notification from the video controller 110 that the generation of image data has been completed, it notifies the video controller 110 of the timing to send the image data to the exposure unit 2. In response, the video controller 110 sends the image data to the exposure unit 2. The engine controller 100 also controls the components shown in FIG. 1 so that an image is formed on the sheet S based on the image data sent by the video controller 110 to the exposure unit 2. At time t10, when the image formation on the second side is completed, the engine controller 100 transports the sheet S toward the processing device 300.

[0046] As described above, according to this embodiment, the density of the adhesive image Tk is controlled based on the type of the sheet S. Therefore, the density of the adhesive image Tk can be appropriately controlled.

[0047] Second Embodiment Next, the second embodiment will be described, focusing on differences from the first embodiment. In the first embodiment, when the automatic setting mode is set, the video controller 110 generates image data after the engine controller 100 determines the sheet type. In other words, the video controller 110 waits without generating image data until the engine controller 100 determines the sheet type. In the present embodiment, when the automatic setting mode is set, the video controller 110 starts generating image data with the density of the adhesive image Tk set as a first density before the engine controller 100 determines the sheet type. Then, if the density of the adhesive image Tk based on the type of sheet S determined by the engine controller 100 (determined type) is the first density, the image data that was previously started to be generated is used for image formation. On the other hand, if the density determined based on the determination type (hereinafter referred to as determined density) is not the first density, the video controller 110 regenerates image data based on the determined density and uses it for image formation.

[0048] Fig. 9 is a flowchart of the processing executed by the image forming apparatus 1 when the image forming apparatus 1 executes a print job involving booklet creation in the processing device 300. Note that, since the operation of the image forming apparatus 1 when not in the automatic setting mode is the same as in the first embodiment, the processing when not in the automatic setting mode is omitted in the flowchart of Fig. 9. In other words, Fig. 9 shows a flowchart of the processing executed by the image forming apparatus 1 when in the automatic setting mode.

[0049] When the video controller 110 receives a print job, in S20, it sets the density of the adhesive image Tk to a first density, and in S21 starts generating image data. In S22, the engine controller 100 determines the actual type of the sheet S and notifies the video controller 110. In S23, the video controller 110 determines the density (determined density) of the adhesive image Tk based on the sheet type determined by the video controller 110. In S24, the video controller 110 determines whether the determined density is the same as the first density. If the determined density is the same as the first density, in S26, the image data generated in S21 is used for image formation. On the other hand, if the determined density is different from the first density, in S25, the video controller 110 regenerates the image data based on the determined density. In this case, in S26, the image data generated in S25 is used for image formation.

[0050] If the determined concentration is within a predetermined range relative to the first concentration, then in S26, the image data generated in S21 is used; otherwise, the image data generated in S25 is used in S26.

[0051] In S27, the video controller 110 determines whether image formation on all sheets S specified in the print job has been completed, and if not, repeats the process from S20 until completion. Although image formation on the second side is also omitted in Fig. 9, when an adhesive image Tk is formed on the second side, the density of the adhesive image Tk is the density determined in S23.

[0052] Note that when images are formed on N sheets S (N is an integer equal to or greater than 2) in a print job, the first density in image formation on the second and subsequent sheets S may be the density of the adhesive image Tk formed on the previous sheet S. Note that the first density in image formation on the first sheet S is a density determined according to a predetermined standard. That is, in N repetitions of the flowchart in FIG. 9, the first density used in S20 for the first time may be a density determined according to a predetermined standard, and the first density used in S20 for the second and subsequent times may be the density determined in S23, which is the previous time. Generally, the same sheet type is used in one print job, so the number of times image data is regenerated (S25) can be reduced by using the density determined previously as the first density used in S20 for the second and subsequent times.

[0053] The first density used in the first S20 may be a density set as a default or a density based on the type of sheet S set by the user. Alternatively, the first density used in the first S20 may be a density based on the history of sheet types used in past printing. For example, the first density used in the first S20 may be a density determined for the sheet type used in the immediately preceding print job. Alternatively, the first density used in the first S20 may be a density determined for the sheet type most used in the past predetermined period.

[0054] As described above, in this embodiment, before determining the sheet type, image data generation is started with the density of the adhesive image Tk set as the first density. By appropriately setting the first density, it is possible to reduce the frequency of regenerating image data in S25. This reduces the average time from when a print job is received until an image is actually formed on the sheet S.

[0055] [Transformation] 9, in S24, the density of the adhesive image Tk based on the determination type is compared with a predetermined first density. However, if the first density is set to a density based on a preset type of sheet S, the determination type can also be compared with a preset type of sheet S (hereinafter referred to as a set type).

[0056] FIG. 15 is a flowchart of this modified embodiment. Note that FIG. 15 shows a flowchart of processing executed by the image forming apparatus 1 in the automatic setting mode. When the video controller 110 receives a print job, in S50, it determines the density of the adhesive image Tk based on the setting type, and in S51, starts generating image data. The setting type in S50 may be the same as or different from the setting type used when the automatic setting mode is off. In S52, the engine controller 100 determines the actual type of the sheet S and notifies the video controller 110.

[0057] In S53, the video controller 110 determines whether the determination type notified from the engine controller 100 is the same as the set type in S50. If the determination type and the set type are the same, in S56, the image data whose generation started in S51 is used for image formation. On the other hand, if the set type and the determination type are different, in S54, the video controller 110 determines the density (determined density) of the adhesion image Tk based on the determination type, and in S55, regenerates the image data based on the determined density. In this case, in S56, the image data generated in S55 is used for image formation.

[0058] In S57, the video controller 110 determines whether image formation on all sheets S specified in the print job has been completed, and if not, repeats the process from S50 until completion. Although image formation on the second side is also omitted in Fig. 15, when an adhesive image Tk is formed on the second side, the density of the adhesive image Tk is the same as that of the first side.

[0059] In addition, when images are formed on N sheets S (N is an integer of 2 or more) in a print job, the set type (first type) for image formation on the second and subsequent sheets S can be the determined type of the previous sheet S. Generally, the same sheet type is used in a single print job, so the set type used in S50 from the second time onwards can be the determined type from the previous time, thereby reducing the number of times image data is regenerated (S55).

[0060] The setting type (first type) in the first S50 may be a type set as a default or a type set by the user. Alternatively, the setting type used in the first S50 may be determined based on the history of sheet types used in past printing. For example, the setting type used in the first S50 may be the sheet type used in the immediately preceding print job. Alternatively, the setting type used in the first S50 may be the sheet type most used in a predetermined period of time in the past.

[0061] As described above, in this embodiment, before determining the sheet type, image data generation is started with the density of the adhesive image Tk set to the density based on the setting type. By appropriately setting the setting type, it is possible to reduce the frequency of regenerating image data in S55. This reduces the average time from receiving a print job to actually forming an image on the sheet S.

[0062] Third Embodiment Next, the third embodiment will be described, focusing on the differences from the second embodiment. In the second embodiment, in the automatic setting mode, image data was generated using the density of the adhesive image Tk as the first density before determining the actual sheet type. If the determined density was not the first density, the video controller 110 regenerated the image data using the determined density. This embodiment assumes that the sheet type in one print job is the same. Until the engine controller 100 determines the sheet type, image data is generated using the density of the adhesive image Tk as the second density. After the engine controller 100 determines the sheet type, image data is generated based on the determined density.

[0063] Fig. 10 is a flowchart of the processing executed by the image forming apparatus 1 when the image forming apparatus 1 executes a print job involving booklet creation in the processing device 300. Note that, since the operation of the image forming apparatus 1 when not in the automatic setting mode is the same as in the first embodiment, the processing when not in the automatic setting mode is omitted in the flowchart of Fig. 10. In other words, Fig. 10 shows a flowchart of the processing executed by the image forming apparatus 1 when in the automatic setting mode.

[0064] When the video controller 110 receives a print job, in S30, it determines whether the engine controller 100 has determined the actual type of the sheet S and notified the video controller 110. If the engine controller 100 has not yet determined the actual type of the sheet S, in S34, the video controller 110 determines the density of the adhesive image Tk to be the second density. On the other hand, if the engine controller 100 has determined the actual type of the sheet S, in S31, the video controller 110 determines the density based on the type determined by the engine controller 100. In S32, the video controller 110 starts generating image data. If the image data includes adhesive image data for forming the adhesive image Tk, the density of the adhesive image Tk is the density determined in S31 or S34. The image data generated in S32 is used for image formation in S33.

[0065] In S34, the video controller 110 determines whether image formation on all sheets S specified in the print job is complete. If not, the process repeats from S30 until completion. Note that image formation on the second side is also omitted in FIG. 10 . When forming an adhesive image Tk on the second side, if the actual sheet type has been determined when generating image data to be formed on the second side, the video controller 110 generates image data using the density of the adhesive image Tk as the determined density. Therefore, according to this embodiment, if the actual sheet type is undetermined when generating image data for the first side and has been determined when generating image data for the second side, the densities of the adhesive images Tk on the first and second sides may differ. Note that if the actual sheet type has not been determined when generating image data for the first side, image data for the second side may also be generated assuming that the actual sheet type is undetermined.

[0066] [Transformation] 10, image data is generated with the density of the adhesive image Tk set as the second density until the actual sheet type is determined, and after the actual sheet type is determined, image data is generated with the density of the adhesive image Tk set as the determined density based on the actual sheet type. However, for the first predetermined number of sheets in a print job, image data can be generated with the density of the adhesive image Tk set as the second density, and thereafter, image data can be generated based on the determined density. Also, if the number of sheets on which images are formed in a print job is equal to or less than a predetermined number, image data can be generated with the density of the adhesive image Tk set as the second density for all sheets, and if the number is greater than the predetermined number, image data can be generated after the actual sheet type is determined, as in the first embodiment.

[0067] In order to ensure adhesive strength, the second density can be set to the maximum density. Alternatively, in order to ensure adhesive strength, the second density can be set to a density equal to or greater than the maximum density of the densities indicated by the determination information. In other words, the second density can be set to the maximum density or a density higher than the maximum density of the densities of the adhesive image Tk determined based on multiple types of sheets that can be used in the image forming apparatus 1.

[0068] As described above, according to this embodiment, after determining the actual sheet type, it is possible to appropriately control the density of the adhesive image Tk to be formed on the sheet S. Furthermore, since the generation of image data is started before determining the actual sheet type, it is possible to shorten the average time from receiving a print job to actually forming an image on the sheet S. Furthermore, by setting the second density used until determining the actual sheet type to be equal to or greater than the maximum density of the densities indicated by the determination information, it is possible to ensure adhesive strength.

[0069] <Fourth embodiment> Next, the fourth embodiment will be described, focusing on the differences from the first to third embodiments. In the first to third embodiments, the video controller 110 generates image data for forming both the user image and the adhesive image Tk. In this embodiment, the video controller 110 generates user image data for forming the user image and transmits it to the exposure unit 2. Meanwhile, the engine controller 100 generates adhesive image data for forming the adhesive image Tk and transmits it to the exposure unit 2. FIG. 11 shows the control configuration of the image forming apparatus 1 according to this embodiment. In this embodiment, since the engine controller 100 generates adhesive image data for forming the adhesive image Tk, information indicating multiple patterns of the adhesive image Tk and determination information are stored in advance in the memory 102.

[0070] 12 is an explanatory diagram of the areas of the sheet S. A user image area where a user image is formed and two adhesive image areas on either side of the user image area in a direction perpendicular to the conveyance direction of the sheet S are defined on the sheet S. The adhesive image area is an area that includes the edge of the sheet S in a direction perpendicular to the conveyance direction of the sheet S. The user image data generated by the video controller 110 is data for forming an image in the user image area, and the adhesive image data generated by the engine controller 100 is data for forming an image in the adhesive image area.

[0071] 13 is a flowchart of processing executed by the engine controller 100 when the image forming apparatus 1 executes a print job involving booklet production in the processing device 300. The engine controller 100 determines in S40 whether the mode is automatic setting. If the mode is not automatic setting, the engine controller 100 determines the density of the adhesive image Tk based on the type set by the user in S46. On the other hand, if the mode is automatic setting, the engine controller 100 determines the type of the sheet S using the type detection sensor 10 in S41, and determines the density of the adhesive image Tk based on the determined sheet type in S42.

[0072] In S43, the engine controller 100 generates adhesive image data in accordance with the density of the adhesive image Tk determined in S46 or S42. In this embodiment, the video controller 110 generates user image data based on image information received in the print job. When the generation of the adhesive image data is completed and the video controller 110 notifies the engine controller 100 of the completion of the generation of the user image data, in S44 the engine controller 100 controls image formation on the first side of the sheet S based on the user image data and adhesive image data. Specifically, the engine controller 100 notifies the video controller 110 of the timing to transmit the user image data to the exposure unit 2, transmits the adhesive image data to the exposure unit 2, and controls the light emission intensity of the exposure unit 2. Although not shown in FIG. 13 for simplicity, when the adhesive image Tk is formed on the second side of the sheet S, the density of the adhesive image Tk formed on the second side is also determined in S42 or S46. The engine controller 100 determines in S45 whether image formation on all sheets S specified in the print job has been completed, and if not, repeats the process from S40 until completion.

[0073] 14(A) and 14(B) are timing charts for transmitting user image data and adhesive image data to the exposure unit 2 in image formation on a certain surface of a sheet. Note that FIG. 14(A) shows a case where, in the exposure of one line, the user image is formed first and then the adhesive image Tk is formed, while FIG. 14(B) shows a case where, in the exposure of one line, the adhesive image Tk is formed first and then the user image is formed. The horizontal synchronization signal is a signal transmitted by the engine controller 100 to the video controller 110. The horizontal synchronization signal is used to determine the start timing of formation of one line, i.e., the timing at which the video controller 110 transmits image data to the exposure unit 2.

[0074] In Fig. 14(A), the timing at which the formation of the user image in the user image area begins is a period ta after the timing of the horizontal synchronization signal. Therefore, the video controller 110 starts transmitting the user image data Vi of the i-th line to the exposure unit 2 after the period ta has elapsed since receiving the horizontal synchronization signal. Also, in Fig. 14(A), the timing at which the formation of the adhesive image Tk in the adhesive image area begins is a period tb after the timing of the horizontal synchronization signal. Therefore, the engine controller 100 starts transmitting the adhesive image data Ci of the i-th line to the exposure unit 2 after the period tb has elapsed since receiving the horizontal synchronization signal.

[0075] In Fig. 14(B), the timing at which the formation of the adhesive image Tk in the adhesive image area begins is a period tc after the timing of the horizontal synchronization signal. Therefore, the engine controller 100 starts transmitting the adhesive image data Ci of the i-th line to the exposure unit 2 when the period tc has elapsed since the horizontal synchronization signal. Also, in Fig. 14(B), the timing at which the formation of the user image in the user image area begins is a period ta after the timing of the horizontal synchronization signal. Therefore, the video controller 110 starts transmitting the user image data Vi of the i-th line to the exposure unit 2 when the period ta has elapsed since receiving the horizontal synchronization signal.

[0076] As described above, according to this embodiment, image data is divided into user image data for forming a user image and adhesive image data for forming an adhesive image. Therefore, upon receiving a print job, the video controller 110 can start generating user image data without waiting for the sheet type determination result. Furthermore, in the automatic setting mode, the engine controller 100 starts generating adhesive image data after determining the sheet type. For example, depending on the position of the adhesive image to be formed on the sheet S, the average time from receiving the print job to actually forming the image on the sheet S can be shortened. Note that, like the first embodiment, the flowchart in FIG. 13 starts generating adhesive image data after determining the sheet type. However, like the second and third embodiments, it is also possible to configure the generation of image data to start before determining the sheet type.

[0077] [Other embodiments] The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0078] The disclosure of this embodiment includes the following configuration. (Configuration 1) an image forming means for forming an image on a sheet based on the first image data; a control means for generating the first image data and outputting it to the image forming means; Equipped with In an image forming device, in response to receiving a print job to form images on multiple sheets and adhere them to each other, when forming the images on the sheets including an adhesive image to be used as an adhesive, the control means determines the density of the adhesive image based on the type of the sheets. (Configuration 2) Further, a sensor for determining the type of the sheet is provided, 2. The image forming apparatus according to claim 1, wherein the control unit determines the type of the sheet by using the sensor. (Configuration 3) The sensor detects the basis weight and the surface property of the sheet, 3. The image forming apparatus according to claim 2, wherein the control unit determines the type of the sheet based on the basis weight and surface properties of the sheet detected by the sensor. (Configuration 4) The image forming apparatus according to configuration 2 or 3, wherein when the image including the adhesive image is formed on the sheet, the control means determines the density of the adhesive image based on the judgment type of the sheet judged using the sensor, and generates the first image data after determining the density of the adhesive image. (Configuration 5) The image forming apparatus of configuration 2 or 3, wherein when the image including the adhesive image is formed on the sheet, the control means generates second image data using the density of the adhesive image as a first density before determining the type of the sheet using the sensor, and when the density of the adhesive image based on the determination type of the sheet determined using the sensor is different from the first density, determines the density of the adhesive image based on the determination type and generates the first image data. (Configuration 6) 6. The image forming apparatus according to configuration 5, wherein, when the density of the adhesion image based on the determination type is the same as the first density, the control unit outputs the second image data to the image forming unit as the first image data. (Configuration 7) The image forming apparatus of configuration 5 or 6, wherein, in forming an image on a first sheet of the plurality of sheets, the first density is a density that is set in advance, and, in forming images on a second or subsequent sheet of the plurality of sheets, the first density is a density based on the determination type of the sheet on which the previous image was formed. (Configuration 8) The image forming apparatus of configuration 2 or 3, wherein when the image including the adhesive image is formed on the sheet, the control means generates second image data assuming that the type of the sheet is a first type before determining the type of the sheet using the sensor, and when the determined type of the sheet determined using the sensor is different from the first type, determines the density of the adhesive image based on the determined type and generates the first image data. (Configuration 9) 9. The image forming apparatus according to configuration 8, wherein, when the determined type is the same as the first type, the control means outputs the second image data to the image forming means as the first image data. (Configuration 10) The image forming apparatus of configuration 8 or 9, wherein, in forming an image on a first sheet of the plurality of sheets, the first type is a predetermined density, and, in forming images on a second or subsequent sheet of the plurality of sheets, the first type is the determined type of the sheet on which the previous image formation was performed. (Configuration 11) In the image forming apparatus of configuration 2 or 3, in forming images on the plurality of sheets, the control means generates the first image data with the density of the adhesive image as a second density before determining the type of the sheet using the sensor, and after determining the type of the sheet using the sensor, determines the density of the adhesive image based on the determined type determined using the sensor and generates the first image data. (Configuration 12) When the number of the plurality of sheets is equal to or less than a predetermined number, the control means generates the first image data for each of the plurality of sheets, with the density of the adhesive image set as a second density; When the number of the plurality of sheets is greater than the predetermined number, the control means generates the first image data for the predetermined number of sheets on which images are to be formed first among the plurality of sheets, with the density of the adhesive image set to the second density, and for the remaining sheets, determines the density of the adhesive image based on the judgment type of the sheet judged using the sensor, and generates the first image data. (Configuration 13) When the number of the plurality of sheets is equal to or less than a predetermined number, the control means generates the first image data for each of the plurality of sheets, with the density of the adhesive image set as a second density; The image forming apparatus of configuration 2 or 3, wherein when the number of the plurality of sheets is greater than the predetermined number, the control means determines the density of the adhesive image for each of the plurality of sheets based on the judgment type of the first sheet judged using the sensor, and generates the first image data. (Configuration 14) 14. The image forming apparatus of any one of configurations 11 to 13, wherein the second density is equal to or greater than the maximum density of the densities of the adhesive images determined for each of a plurality of types of the sheets used in the image forming apparatus. (Configuration 15) the first image data includes third image data for forming an image in a first region of the sheet, and fourth image data for forming images in second regions on both sides of the first region in a direction perpendicular to a conveyance direction of the sheet, the adhesive image is formed in the second region, and an image different from the adhesive image among the images formed on the sheet is formed in the first region; 15. The image forming apparatus of any one of configurations 1 to 14, wherein the control means includes a first controller that generates the third image data and a second controller that generates the fourth image data. (Configuration 16) 16. The image forming apparatus according to any one of configurations 1 to 15, wherein when a mode using a type set by a user is set, the control means determines the density of the adhesive image based on the type set by the user and generates the first image data. (Configuration 17) an image forming apparatus according to any one of configurations 1 to 16; a processing device that sequentially stacks the sheets on which the images are formed by the image forming device and performs a bonding process on the stacked sheets; An image forming system comprising:

[0079] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0080] 110: Video controller, 100: Engine controller, 7n, 7y, 7m, 7c: Process units, 2: Exposure unit, 3: Intermediate transfer belt, 5: Secondary transfer roller, 6: Fixing unit

Claims

1. an image forming means for forming an image on a sheet based on the first image data; a control means for generating the first image data and outputting the first image data to the image forming means; Equipped with In an image forming device, in response to receiving a print job to form images on multiple sheets and adhere them to each other, when forming the images on the sheets including an adhesive image to be used as an adhesive, the control means determines the density of the adhesive image based on the type of the sheets.

2. Further, a sensor for determining the type of the sheet is provided, 2. The image forming apparatus according to claim 1, wherein the control unit determines the type of the sheet by using the sensor.

3. The sensor detects the basis weight and the surface property of the sheet, 3. The image forming apparatus according to claim 2, wherein the control unit determines the type of the sheet based on the basis weight and surface properties of the sheet detected by the sensor.

4. 3. The image forming apparatus according to claim 2, wherein when the image including the adhesive image is formed on the sheet, the control means determines the density of the adhesive image based on the judgment type of the sheet determined using the sensor, and generates the first image data after determining the density of the adhesive image.

5. 3. The image forming apparatus according to claim 2, wherein, when the image including the adhesive image is formed on the sheet, the control means generates second image data using the density of the adhesive image as a first density before determining the type of the sheet using the sensor, and when the density of the adhesive image based on the determined type of the sheet determined using the sensor is different from the first density, determines the density of the adhesive image based on the determined type and generates the first image data.

6. 6. The image forming apparatus according to claim 5, wherein when the density of the adhesion image based on the determination type is the same as the first density, the control unit outputs the second image data to the image forming unit as the first image data.

7. 6. The image forming apparatus according to claim 5, wherein, when forming an image on a first sheet of the plurality of sheets, the first density is a density that is set in advance, and when forming an image on a second or subsequent sheet of the plurality of sheets, the first density is a density based on the determination type of the sheet on which the previous image was formed.

8. 3. The image forming apparatus of claim 2, wherein when the image including the adhesive image is formed on the sheet, the control means generates second image data assuming that the type of the sheet is a first type before determining the type of the sheet using the sensor, and when the determined type of the sheet determined using the sensor is different from the first type, determines the density of the adhesive image based on the determined type and generates the first image data.

9. 9. The image forming apparatus according to claim 8, wherein when the determined type is the same as the first type, the control unit outputs the second image data to the image forming unit as the first image data.

10. 9. The image forming apparatus according to claim 8, wherein, when forming an image on a first sheet of the plurality of sheets, the first type is a pre-set type, and when forming an image on a second or subsequent sheet of the plurality of sheets, the first type is the determined type of the sheet on which the previous image formation was performed.

11. 3. The image forming apparatus according to claim 2, wherein, in forming images on the plurality of sheets, the control means generates the first image data with the density of the adhesive image as a second density before determining the type of the sheet using the sensor, and after determining the type of the sheet using the sensor, determines the density of the adhesive image based on the determined type determined using the sensor and generates the first image data.

12. When the number of the plurality of sheets is equal to or less than a predetermined number, the control means generates the first image data for each of the plurality of sheets, with the density of the adhesive image set as a second density; 3. The image forming apparatus according to claim 2, wherein, when the number of the plurality of sheets is greater than the predetermined number, the control means generates the first image data for the predetermined number of sheets among the plurality of sheets on which an image is to be formed first, with the density of the adhesive image set to the second density, and for the remaining sheets, determines the density of the adhesive image based on the judgment type of the sheet judged using the sensor, and generates the first image data.

13. When the number of the plurality of sheets is equal to or less than a predetermined number, the control means generates the first image data for each of the plurality of sheets, with the density of the adhesive image set as a second density; 3. The image forming apparatus according to claim 2, wherein when the number of the plurality of sheets is greater than the predetermined number, the control means determines the density of the adhesive image for each of the plurality of sheets based on the judgment type of the first sheet judged using the sensor, and generates the first image data.

14. The image forming apparatus according to claim 11 , wherein the second density is equal to or greater than a maximum density among densities of the adhesive images determined for each of a plurality of types of the sheets used in the image forming apparatus.

15. the first image data includes third image data for forming an image in a first region of the sheet, and fourth image data for forming images in second regions on both sides of the first region in a direction perpendicular to a conveyance direction of the sheet, the adhesive image is formed in the second area, and an image different from the adhesive image among the images formed on the sheet is formed in the first area; 14. The image forming apparatus according to claim 1, wherein the control unit includes a first controller that generates the third image data and a second controller that generates the fourth image data.

16. 14. The image forming apparatus according to claim 1, wherein when a mode using a type set by a user is set, the control unit determines the density of the adhesive image based on the type set by the user and generates the first image data.

17. The image forming apparatus according to any one of claims 1 to 13, a processing device that sequentially stacks the sheets on which the images are formed by the image forming device and performs a bonding process on the stacked sheets; An image forming system comprising:

Images