Image forming apparatus and sheet bonding apparatus

Abstract

To provide an image forming apparatus capable of improving the quality of a finished product.SOLUTION: An image forming apparatus includes: image forming means for forming an image on a sheet and applying an adhesive toner to the sheet; and bonding means with a pressure member, which performs a bonding operation in which the pressure member applies pressure and heat to a stack of sheets, thereby bonding the sheets together with the adhesive toner. The bonding means performs a next bonding operation in a state in which a subsequent sheet is stacked on a bonded sheet stack bonded in the previous bonding operation, thereby bonding a first surface of a top sheet of the bonded sheet stack and a second surface of the subsequent sheet opposite to the first surface. The amount of the adhesive toner applied to the first surface by the image forming means is smaller than the amount of the adhesive toner applied to the second surface by the image forming means.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus for forming an image on a sheet, and a sheet bonding apparatus for bonding sheets. [Background technology]

[0002] Patent Document 1 describes an image forming apparatus that uses an electrophotographic process to form an adhesive toner pattern on paper in addition to a visible image for recording information, and then stacks and heats the sheets to bond them together with the adhesive toner pattern. Patent Document 2 describes an image forming apparatus that creates a larger number of sheet bundles by repeatedly heating and pressing three sheets at a time with a heating and pressing member, the sheets having adhesive toner layers formed thereon. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-43751 A [Patent Document 2] JP 2005-215230 A Summary of the Invention [Problem to be solved by the invention]

[0004] In an apparatus for bonding sheets together using adhesive toner as in the above-mentioned documents, it has been desired to be able to change the amount of toner in the bonding portion as required.

[0005] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide an image forming apparatus capable of changing the amount of toner in the adhesive portion as required. [Means for solving the problem]

[0006] One aspect of the present invention is an image forming apparatus comprising an image forming means for forming an image on a sheet and applying adhesive toner to the sheet, and an adhesive means having a pressure member and performing a bonding operation in which the pressure member applies pressure and heat to the sheet stack to bond the sheets together with the adhesive toner, wherein the adhesive means performs the next bonding operation in a state in which a subsequent sheet is stacked on top of the bonded sheet stack bonded in the previous bonding operation, thereby bonding a first surface of the top sheet of the bonded sheet stack to a second surface of the subsequent sheet opposite the first surface, and the amount of the adhesive toner applied to the first surface by the image forming means is less than the amount of the adhesive toner applied to the second surface by the image forming means.

[0007] Another aspect of the present invention is an image forming apparatus comprising an image forming means for forming an image and an adhesive toner image on a sheet, and an adhesive means for adhering the sheets together with the adhesive toner image by applying pressure and heat to a stack of sheets, wherein the image forming means forms the image using toner in an image area of ​​the sheet, and forms the adhesive toner image using the toner in an adhesive area of ​​the sheet different from the image area, and the amount of toner per unit area in the adhesive area is different from the amount of toner per unit area in the image area.

[0008] Another aspect of the present invention is a sheet bonding device comprising an application means for applying adhesive toner to a sheet, and an adhesive means having a pressure member and performing a bonding operation in which the pressure member applies pressure and heat to the sheet stack, thereby bonding the sheets together with the adhesive toner, wherein the adhesive means performs the next bonding operation in a state in which a subsequent sheet is stacked on top of the bonded sheet stack bonded in the previous bonding operation, thereby bonding a first surface of the top sheet of the bonded sheet stack to a second surface of the subsequent sheet opposite the first surface, and the amount of the adhesive toner applied to the first surface by the application means is less than the amount of the adhesive toner applied to the second surface by the application means. Effect of the Invention

[0009] According to the present invention, an image forming apparatus capable of changing the amount of toner in the adhesive portion as required can be provided. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic diagram of an image forming apparatus according to a first embodiment. [Diagram 2] 5A to 5D are diagrams for explaining the operation of the booklet producing device according to the first embodiment. [Diagram 3] FIG. 2 is a cross-sectional view of a thermocompression bonding unit according to the first embodiment. [Figure 4] FIG. 4 is a diagram showing sheet positions for each size in the first embodiment. [Diagram 5] 3A and 3B are diagrams showing examples of adhesive regions in Example 1. [Figure 6] FIG. 4A is a graph showing the relationship between the amount of adhesive toner and adhesive force in the first embodiment, and FIG. [Figure 7] 3A to 3C are diagrams showing the process of producing a booklet in Example 1. [Figure 8] 3A to 3C are diagrams showing the process of producing a booklet in Example 1. [Figure 9] 6A and 6B are diagrams showing the relationship between the amount of adhesive toner on opposing surfaces of sheets and adhesive strength. [Figure 10] 6 is a graph showing the relationship between the amount of adhesive toner, the adhesive strength of a completed booklet, and the toner adhesion to a back cover in the first embodiment. FIG. [Figure 11] FIG. 2 is a diagram illustrating a drive circuit of the scanner unit according to the first embodiment. [Figure 12] FIG. 11 is a schematic diagram of an image forming apparatus according to a second embodiment. [Figure 13] FIG. 11 is a graph showing the relationship between the amount of exposure light and the amount of toner in the second embodiment. [Figure 14] FIG. 11 is a diagram illustrating a drive circuit of a scanner unit according to a second embodiment. [Figure 15] 6A and 6B are timing charts showing exposure control according to the second embodiment. [Figure 16] 11A and 11B are schematic diagrams showing the relationship of the toner amount on a sheet in the second embodiment. [Figure 17] 11A and 11B are timing charts showing exposure control according to the third embodiment. [Figure 18] 10A and 10B are timing charts showing exposure control according to the fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Example 1

[0012] (Overall configuration of image forming apparatus) First, the overall configuration of the image forming apparatus will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing a cross-sectional configuration of an image forming apparatus 1S according to a first embodiment.

[0013] The image forming apparatus 1S includes a printer section 1 (image forming apparatus main body) equipped with an electrophotographic image forming unit 1e, an intermediate conveying unit 26 connected to the printer section 1, and a post-processing apparatus 4 (sheet processing apparatus) connected to the intermediate conveying unit 26. The image forming apparatus 1S is an image forming system made up of a plurality of apparatuses. However, the functions of the respective apparatuses equipped in the image forming apparatus 1S of this embodiment may be arranged in one housing.

[0014] 1, the printer section 1 includes a cassette 8 that stores sheets P, an image forming unit 1e (enclosed in a dashed line frame) as an image forming means, a fixing device 6 as a fixing means, and a housing 19 that houses these. The printer section 1 has a printing function (image forming function) that forms a toner image on the sheet P fed from the cassette 8 by the image forming unit 1e, and performs a fixing process by the fixing device 6 to produce a printed matter. Note that the sheet P, which is the recording material (recording medium), can be a variety of sheet materials of different sizes and materials, such as paper such as plain paper and cardboard, sheet materials with surface treatments such as plastic film, cloth, and coated paper, and sheet materials with special shapes such as envelopes and index paper.

[0015] In this embodiment, the maximum size of the sheet P on which the printer unit 1 can form an image is A4 size (297 mm length × 210 mm width). The printer unit 1 can form an image by transporting the A4 size sheet P in the vertical direction (long side feed direction, the direction in which the vertical side of the A4 size sheet P is parallel to the sheet transport direction).

[0016] The image forming unit 1e is a tandem-type intermediate transfer electrophotographic unit equipped with four process cartridges 7n, 7y, 7m, and 7c, a scanner unit 2 as an exposure device, and a transfer unit 3. A process cartridge is a unit in which multiple parts responsible for the image forming process are integrated into one replaceable unit.

[0017] As described later, the image forming unit 1e also functions as an application unit that applies adhesive to the sheet P. The image forming apparatus 1S including the image forming unit 1e as the application unit and a booklet production device 50 described later is an example of a sheet bonding apparatus that produces a product in which the sheets P are bonded together.

[0018] Each of the process cartridges 7n, 7y, 7m, and 7c includes a photosensitive drum Dn, Dy, Dm, or Dc serving as an image carrier, a charging roller, and a developing unit. Each charging roller functions as a charging means for charging the corresponding photosensitive drum Dn, Dy, Dm, or Dc. Each developing unit includes a toner storage section that stores toner as a developer, and a developing roller that serves as a developer carrier that carries the toner, and supplies the toner to the corresponding photosensitive drum Dn, Dy, Dm, or Dc.

[0019] Of the four process cartridges 7n, 7y, 7m, and 7c, the three process cartridges 7y, 7m, and 7c from the right end in the figure are process cartridges for forming a visible image on a sheet P. The process cartridges 7y, 7m, and 7c create yellow, magenta, and cyan toner images, respectively. The yellow, magenta, and cyan toners contained in the process cartridges 7y, 7m, and 7c are image toners (recording toners that record information) for forming an image on a sheet P.

[0020] In contrast, the process cartridge 7n on the left side of the figure is a process cartridge for applying adhesive toner (adhesive toner, powder adhesive, powder adhesive) to adhere sheets to each other after printing to the sheet P. The process cartridge 7n creates a toner image of adhesive toner (adhesive toner image) for applying adhesive to the sheet P by the same electrophotographic process as the process cartridges 7n, 7y, 7m, 7c. In other words, some of the multiple process cartridges 7n, 7y, 7m, 7c included in the image forming unit 1e create a visible image using toner, and other cartridges form an adhesive layer on the sheet P using adhesive toner. The adhesive toner may be a colorless transparent toner or a colored toner.

[0021] In this embodiment, when forming a black image such as text, the black color is expressed by process black obtained by superimposing yellow, magenta, and cyan toners. However, for example, a fifth process cartridge using black toner may be added to the image forming unit 1e so that a black image can be expressed by black image toner. However, the present invention is not limited to this, and the types and numbers of image toners and adhesive toners can be changed depending on the application of the image forming apparatus 1S.

[0022] (Scanner unit) The following describes the laser drive circuit mounted on the scanner unit 2. FIG.

[0023] The scanner unit 2 is an example of an exposure unit that forms an electrostatic latent image by irradiating light to the photosensitive drums Dn, Dy, Dm, and Dc of each process cartridge 7n, 7y, 7m, and 7c to expose them. The scanner unit 2 includes a semiconductor laser 100 as a light source, a polygon mirror 101, a synchronization sensor 102, and a laser driving circuit 115. The laser driving circuit 115 includes a light emission control unit 103 and a driving current generating unit 104. Four sets of the semiconductor laser 100, the synchronization sensor 102, and the laser driving circuit 115 are arranged corresponding to the four photosensitive drums Dn, Dy, Dm, and Dc. FIG. 11 illustrates one set of circuits corresponding to the photosensitive drum D, which is any one of the four photosensitive drums Dn, Dy, Dm, and Dc.

[0024] Laser light L1 emitted from the semiconductor laser 100 is reflected by a polygon mirror 101 that is rotated. The reflected scanning light L3 scans the surface of the photosensitive drum D in the main scanning direction via an fθ lens (not shown). In addition, a part of the laser light L1 emitted from the semiconductor laser 100, light L2, scans a synchronization sensor 102, and a main scanning synchronization signal 108 is output from the synchronization sensor 102.

[0025] The image forming apparatus 1S includes a controller 107 as a control means for controlling the image forming apparatus 1S, and a CPU 106. The controller 107 outputs an image signal 109 corresponding to each color based on a main scanning synchronization signal 108 to a light emission control unit 103. The light emission control unit 103 outputs a laser drive current 112, which is a current supplied to the semiconductor laser 100, in accordance with the image signal 109, and drives and controls the semiconductor laser 100.

[0026] The CPU 106 performs serial communication with the drive current generating unit 104 via a serial communication signal 110. The drive current generating unit 104 outputs a laser drive current amount signal 111 based on information transmitted from the CPU 106, and controls the amount of laser drive current 112. The laser drive current 112 is controlled to a current amount based on the laser drive current amount signal 111. The laser light irradiated from the scanner unit 2 to each photosensitive drum D in this embodiment has a predetermined light amount regardless of the position in the main scanning direction.

[0027] (Image toner) As the image toner of this embodiment, a known image toner can be used. Among them, an image toner using a thermoplastic resin as a binder resin is preferred. The thermoplastic resin is not particularly limited, and resins that have been used in image toners in the past, such as polyester resin, vinyl resin, acrylic resin, and styrene-acrylic resin, can be used. A plurality of these resins may be contained. The image toner contains a colorant, a magnetic material, a charge control agent, wax, an external additive, and the like.

[0028] (Adhesive Toner) The adhesive toner of this embodiment may be a toner containing a thermoplastic resin. Resins that may be used for the thermoplastic resin are not particularly limited, and include polyester resins, vinyl resins, acrylic resins, styrene-acrylic resins, etc., as in the image toner. A plurality of these resins may be contained. The adhesive toner may also contain colorants, magnetic materials, charge control agents, wax, external additives, etc., as in the image toner. In addition, the same toner as the image toner may be used as the adhesive toner as long as it satisfies the adhesive property.

[0029] (Transfer unit) The transfer unit 3 of this embodiment includes a transfer belt 3a as an intermediate transfer body (secondary image carrier), a secondary transfer opposing roller 3b, and a drive roller 3c. The transfer belt 3a is a belt member stretched around the secondary transfer opposing roller 3b and the drive roller 3c. The outer circumferential surface of the transfer belt 3a faces the photosensitive drums Dn, Dy, Dm, and Dc of the process cartridges 7n, 7y, 7m, and 7c. Primary transfer rollers Fn, Fy, Fm, and Fc are disposed on the inner circumferential side of the transfer belt 3a at positions corresponding to the photosensitive drums Dn, Dy, Dm, and Dc. The transfer belt 3a is transported in the counterclockwise direction in the figure by the rotational drive of the drive roller 3c.

[0030] The printer unit 1 includes a secondary transfer roller 5 as a transfer means at a position facing the secondary transfer opposing roller 3b across the transfer belt 3a. A transfer nip 5n between the secondary transfer roller 5 and the transfer belt 3a is a transfer unit (secondary transfer unit) for transferring a toner image from the transfer belt 3a to the sheet P.

[0031] (Fixing device) The fixing device 6 is an example of a fixing means for fixing the toner image formed on the sheet P to the sheet P. The fixing device 6 is a thermal fixing type device (image heating device) that fixes the toner image by heating.

[0032] The fixing device 6 has a heating roller 6b as a fixing member, a halogen heater 6a as a heat source (heating means) built into the heating roller 6b, and a pressure roller 6c as a member facing the heating roller 6b. The heating roller 6b is driven to rotate by a driving source. In addition, the heating roller 6b and the pressure roller 6c are pressed against each other by a biasing member such as a spring, and a fixing nip 6n is formed between the heating roller 6b and the pressure roller 6c.

[0033] The fixing device 6 includes a temperature detection element such as a thermistor that detects the temperature of the heating roller 6b. The control means of the image forming apparatus 1S adjusts the input power to the halogen heater based on the detection signal of the temperature detection element, thereby controlling the temperature of the heating roller 6b to a predetermined target temperature (fixing temperature).

[0034] The heat source (heating means) may be a ceramic heater having a pattern of a heating resistor formed on a ceramic substrate, or an induction heating mechanism that heats a conductive layer in the heating roller 6b by induction heating, etc. The fixing member is not limited to the heating roller 6b having rigidity, and may be a film formed of a thin film of a polyimide resin or polyamide-imide resin as a highly heat-resistant resin, or a metal such as stainless steel.

[0035] (Image formation operation) The image forming operation of the printer unit 1 will be described (see FIG. 1). The image forming operation is a series of operations in which the printer unit 1 conveys the sheets P one by one, creates a toner image on the sheets P with image toner, and applies adhesive toner to a predetermined adhesive area on the sheets P. When a print instruction accompanied by image data to be printed is input to the image forming apparatus 1S, the control means of the image forming apparatus 1S starts the image forming operation.

[0036] When the image forming operation is started, the sheets P stored in the cassette 8 are fed one by one from the cassette 8 by the feeding roller 8a. The printer unit 1 can also feed the sheets P set in the multi-tray 20 (manual feed tray, multipurpose tray) one by one. The fed sheets P are transported toward the transfer nip 5n by the transport roller pair 8b.

[0037] In parallel with the feeding of the sheet P, in the image forming unit 1e, the process cartridges 7n, 7y, 7m, and 7c are sequentially driven, and the photosensitive drums Dn, Dy, Dm, and Dc are rotated. The surfaces of the photosensitive drums Dn, Dy, Dm, and Dc are uniformly charged by charging rollers. In addition, the scanner unit 2 irradiates the photosensitive drums Dn, Dy, Dm, and Dc with laser light modulated based on image data, thereby forming electrostatic latent images on the surfaces of the photosensitive drums Dn, Dy, Dm, and Dc.

[0038] The developing unit of each process cartridge 7n, 7y, 7m, 7c develops the electrostatic latent image into a toner image by carrying toner (image toner, adhesive toner) as a developer on a developing roller and supplying it to each photosensitive drum Dn, Dy, Dm, Dc. Note that the adhesive toner image formed on the photosensitive drum Dn by the adhesive toner is different from a toner image (normal toner image) of image toner for printing images such as text and figures on the sheet P in that it is not intended to transmit visual information. However, in the following description, the adhesive toner image developed by the electrophotographic process to form an adhesive toner image in a predetermined pattern on the sheet P is also treated as one of the "toner images."

[0039] The toner images formed in each process cartridge 7n, 7y, 7m, 7c are transferred (primary transfer) from each photosensitive drum to the transfer belt 3a by an electric field formed between the photosensitive drums Dn, Dy, Dm, Dc and the primary transfer rollers Fn, Fy, Fm, Fc. The toner images carried on the transfer belt 3a and reaching the transfer nip 5n are transferred (secondary transfer) to the sheet P fed and conveyed from the cassette 8 by an electric field formed between the secondary transfer roller 5 and the secondary transfer opposing roller 3b.

[0040] Thereafter, the sheet P is conveyed to the fixing device 6 and subjected to a thermal fixing process. That is, when the sheet P passes through the fixing nip 6n, the toner image on the sheet P is heated and pressurized, so that the image toner and adhesive toner melt, and then are fixed to the sheet P.

[0041] A reversing flap 21 is disposed downstream of the fixing nip 6n in the sheet transport direction. The reversing flap 21 is a guide member for switching the transport path of the sheet P based on single-sided / double-sided settings specified in a print instruction.

[0042] In the case of a single-sided mode (single-sided printing) in which a toner image is formed only on one side of the sheet P, the reversing flap 21 guides the sheet P toward the discharge roller pair 22. In the case of a double-sided mode (double-sided printing) in which an image is formed on both sides of the sheet P, the reversing flap 21 guides the sheet P with the toner image formed on the front side toward the reversing roller pair 23 (switchback roller pair). The reversing roller pair 23 conveys the sheet P in a first direction, and then switches back to convey the sheet P in a second direction opposite to the first direction before the rear end of the sheet passes through the nip of the reversing roller pair 23. The sheet P switched back by the reversing roller pair 23 is conveyed via the double-sided conveying path 27, and passes through the transfer nip 5n and the fixing nip 6n again, thereby forming a toner image on the rear side. The sheet P with the toner image formed on the rear side is guided by the reversing flap 21 toward the discharge roller pair 22.

[0043] The discharge roller pair 22 discharges the sheet P to the outside of the printer unit 1. This completes the image forming operation for one sheet P. In this embodiment, the sheet P discharged from the discharge roller pair 22 is received by the intermediate transport unit 26. The intermediate transport unit 26 transports the sheet P toward the post-processing device 4 by the transport roller pairs 24 and 25.

[0044] (After-treatment device) 1, the post-processing device 4 of this embodiment has a floor-standing configuration. In other words, the post-processing device 4 is installed on the installation surface on which the printer unit 1 is installed, and is arranged horizontally alongside the printer unit 1. Note that the image forming apparatus 1S may have a configuration in which the post-processing device 4 including the booklet making device 50 is placed on top of the printer unit 1, for example.

[0045] The post-processing device 4 includes a conveying path for conveying the sheet P received from outside, a plurality of pairs of conveying rollers arranged along the conveying path, a booklet making device 50 for making a booklet by gluing a plurality of sheets P together, an upper discharge tray 33 and a lower discharge tray 34.

[0046] In this embodiment, the multiple transport roller pairs are an entrance roller pair 30, a first roller pair 31, a discharge reverse roller pair 32, a second roller pair 36, a third roller pair 37, an inner discharge roller pair 38, and a booklet discharge roller pair 39. The entrance roller pair 30, the first roller pair 31, and the discharge reverse roller pair 32 are arranged on a first transport path from a receiving entrance that receives the sheet P from the outside toward the upper discharge tray 33. The second roller pair 36, the third roller pair 37, and the inner discharge roller pair 38 are arranged on a second transport path from the discharge reverse roller pair 32 toward the booklet production device 50. The booklet discharge roller pair 39 is arranged on a third transport path from the booklet production device 50 toward the lower discharge tray 34.

[0047] The upper discharge tray 33 is a stacking section on which sheets P that are not processed by the booklet production device 50 are stacked. The lower discharge tray 34 is a stacking section on which booklets processed by the booklet production device 50 are stacked. The pair of discharge reversing rollers 32 is a discharge means for discharging the sheet P to the upper discharge tray 33. The pair of discharge reversing rollers 32 is also a reversing means for switching back the sheet P transported on the first transport path and sending it to the second transport path. The pair of booklet discharge rollers 39 is a discharge means for discharging the booklet transported on the third transport path. The housing of the post-processing device 4 is provided with a discharge outlet from which the sheet P is discharged toward the upper discharge tray 33 and a booklet discharge outlet 40 from which the booklet is discharged toward the lower discharge tray 34.

[0048] The operation of the post-processing device 4 will be described. The sheet P conveyed from the intermediate conveying unit 26 passes through an inlet roller pair 30 and a first roller pair 31, and is conveyed to a discharge reverse roller pair 32. When the printing instruction specifies that the sheet P is not to be subjected to adhesive processing (no booklet is to be produced), the sheet P is directly discharged by the discharge reverse roller pair 32 and stacked on a discharge upper tray 33.

[0049] When the printing instruction specifies that the sheet P should be glued (a booklet should be produced), the sheet P is switched back by the discharge / reverse roller pair 32. That is, the discharge / reverse roller pair 32 transports the sheet P in a first direction (discharge direction), and when the rear end of the sheet P in the first direction passes through the reversal flap 35, the discharge / reverse roller pair 32 reverses the sheet transport direction to a second direction opposite to the first direction, and sends the sheet P into the second transport path. The sheet P passes through a second roller pair 36 and a third roller pair 37, and is discharged to the booklet production device 50 by the inner discharge roller pair 38.

[0050] The booklet producing device 50 produces a booklet by adhering a plurality of sheets P together with adhesive toner. Details of the booklet producing device 50 will be described later. The booklet discharge roller pair 39 discharges the booklet conveyed from the booklet producing device 50 to the outside of the post-processing device 4 through the booklet discharge port 40. The discharged booklet is stacked on the lower discharge tray 34.

[0051] (Booklet production device) Next, a description will be given of the booklet production apparatus 50. As shown in Fig. 1, the booklet production apparatus 50 has an intermediate stacking section 51 as a stacking section on which a sheet bundle to be processed is stacked, an alignment mechanism that aligns the stacked sheet bundle, and a thermocompression bonding unit 60 that thermocompresses the sheet bundle.

[0052] The alignment mechanism aligns the sheets conveyed to the intermediate stacking section 51 to a position for thermocompression bonding (adhesive operation) by the thermocompression bonding unit 60. A method of aligning a sheet stack using the alignment mechanism will be described with reference to Figs. 2(a) to (d). Figs. 2(a) to (d) show the booklet making apparatus 50 as viewed from a direction perpendicular to the sheet stacking surface of the intermediate stacking section 51 (height direction). In the following description, the direction along the sheet stacking surface in which the sheets P are conveyed toward the intermediate stacking section 51 is referred to as the "vertical direction" or "X direction", and the direction along the sheet stacking surface that is perpendicular to the vertical direction (X direction) is referred to as the "lateral direction" or "Y direction".

[0053] As shown in Fig. 2(a), the alignment mechanism includes a vertical alignment reference plate 52, a vertical alignment roller 53, a horizontal alignment reference plate 55, and a horizontal alignment claw 54. The vertical alignment reference plate 52 serves as a reference for the sheet position in the vertical direction. The horizontal alignment reference plate 55 serves as a reference for the sheet position in the horizontal direction. The vertical alignment roller 53 is an example of a first moving member that moves the sheet P toward the vertical alignment reference plate 52. The horizontal alignment claw 54 is an example of a second moving member that moves the sheet P toward the horizontal alignment reference plate 55.

[0054] As shown in Fig. 2(a), the sheet P conveyed to the pair of inner discharge rollers 38 is discharged to the intermediate stacking section 51 by the pair of inner discharge rollers 38. As shown in Fig. 2(b), when the rear end of the sheet P in the vertical direction passes through the pair of inner discharge rollers 38, the vertical alignment rollers 53 move the sheet P in the vertical direction, and the end of the sheet P in the vertical direction abuts against the vertical alignment reference plate 52. This aligns the position of the sheet P in the vertical direction.

[0055] 2(c), the lateral alignment claw 54 comes into contact with a first end of the sheet P in the lateral direction, and moves the sheet P toward the lateral alignment reference plate 55. Then, as shown in FIG. 2(d), the second end of the sheet P in the lateral direction abuts against the lateral alignment reference plate 55. This causes the position of the sheet P in the lateral direction to be aligned.

[0056] As described above, the booklet making apparatus 50 aligns each sheet P of the sheet stack stacked on the intermediate stacking section 51 in the vertical and horizontal directions. The thermocompression bonding unit 60, which will be described next, thermocompresses the aligned sheet stack to bond the sheets together via the adhesive toner.

[0057] 2(a) to (d), the case where the sheets P are conveyed one by one to the booklet making device 50 has been described, but a configuration in which a plurality of sheets P in a pre-stacked state are conveyed to the booklet making device 50 may also be used. For example, the preceding sheet P is switched back by the discharge reverse roller pair 32, and then the second roller pair 36 temporarily stops the preceding sheet P. Thereafter, the second roller pair 36 conveys the preceding sheet P toward the discharge reverse roller pair 32 in accordance with the timing at which the subsequent sheet P reaches the discharge reverse roller pair 32. As a result, a sheet bundle in which the preceding sheet P and the subsequent sheet P are overlapped is formed at the discharge reverse roller pair 32. Also, by replacing the "preceding sheet P" with the preceding sheet bundle already overlapped, and replacing the "subsequent sheet" with the subsequent sheet, a sheet bundle of three or more sheets can be produced. The sheet bundle already overlapped by the discharge reverse roller pair 32 is stacked on the intermediate stacking section 51 by the inner discharge roller pair 38 via the second roller pair 36 and the third roller pair 37.

[0058] As described above, the mechanism for stacking the succeeding sheets while reciprocating the preceding sheet (stack) between the pair of discharge and reversing rollers 32 and the pair of second rollers 36 is an example of a buffer mechanism (stacking section) that transports a plurality of sheets in a stacked state toward the intermediate stacking section 51. Other known mechanisms may be used as the buffer mechanism (stacking section).

[0059] When a plurality of sheets P that have been stacked in advance are transported to the booklet production apparatus 50, the alignment mechanism of the booklet production apparatus 50 can perform an alignment operation as follows. When a plurality of sheets P are stacked, the sheets are offset from each other in advance so that the lower sheet P protrudes toward the downstream side in the vertical direction (the side closer to the vertical alignment reference plate 52) than the upper sheet P on the intermediate stacking unit 51. When the rear end of the lowermost sheet P passes through the pair of inner discharge rollers 38, the vertical alignment roller 53 moves the lowermost sheet P in the vertical direction and abuts it against the vertical alignment reference plate 52. Similarly, every time the rear end of the uppermost sheet P passes through the pair of inner discharge rollers 38, the vertical alignment roller 53 moves the sheet P in the vertical direction and abuts it against the vertical alignment reference plate 52. As a result, the positions of the plurality of sheets P in the vertical direction are aligned. After the positions of the multiple sheets P in the vertical direction are aligned, the horizontal alignment claws 54 move the multiple sheets P toward the horizontal alignment reference plate 55 and bring them together against the horizontal alignment reference plate 55. This causes the positions of the multiple sheets P in the horizontal direction to be aligned.

[0060] (Thermocompression unit) The thermocompression unit 60 of the booklet production apparatus 50 will be described. Fig. 3 is a cross-sectional view of the thermocompression unit 60 cut along a plane perpendicular to the vertical direction (X direction). In the description of the booklet production apparatus 50, the direction perpendicular to the sheet stacking surface of the intermediate stacking section 51 (the direction perpendicular to both the X direction and the Y direction) is referred to as the "height direction" or "Z direction". In the description of the booklet production apparatus 50, unless otherwise specified, "downward" refers to the downward direction in the height direction (Z direction), and "upward" refers to the upward direction in the height direction (Z direction).

[0061] The thermocompression bonding unit 60 is an example of a bonding means for bonding sheets together. The thermocompression bonding unit 60 has a pressure plate 62, a receiving plate 67, a heater 70, a heater support 63, a metal stay 66, and a pressure lever 65. The pressure plate 62 is an example of a pressure member (first pressure member, heating and pressure member) that presses the sheet P. The receiving plate 67 is an example of a receiving member (second pressure member) that receives the pressure force of the pressure plate 62 and presses the sheet P together with the pressure plate 62. The heater 70 is an example of a heating means (heat source) that heats the pressure plate 62.

[0062] The heater 70 may be a ceramic heater having a resistance heating element 72 formed on a ceramic substrate 71. The substrate 71 is, for example, a plate having a thickness of 1.0 mm. The pressure plate 62 is in contact with the lower surface of the heater 70 (the surface on the lower side in the figure). The pressure plate 62 is, for example, a plate member made of aluminum having a thickness of 1.5 mm. By reducing the thermal capacity of the heater 70 and the pressure plate 62 in this manner, it is possible to reduce the power consumption of the thermocompression bonding unit 60. Note that the substrate 71 of the heater 70 may be made of a material having high rigidity, such as metal, other than ceramic.

[0063] The pressure plate 62 is suitably made of a material having a small heat capacity and high thermal conductivity in order to efficiently transfer heat from the heat source to the sheet P. The pressure plate 62 is suitably made of a material having an elastic modulus of 1000 Pa or more that is unlikely to deform due to the pressure applied during thermocompression bonding, and preferably a material having a high elastic modulus of 10000 Pa or more is used.

[0064] The heater 70 generates heat when electricity is applied to the resistance heating element 72. A control unit provided in the post-processing device 4 controls the power input to the resistance heating element 72 based on the temperature detected by a thermistor 64 serving as a temperature detection means, thereby heating the pressure plate 62 to a predetermined target temperature suitable for thermocompression bonding of the sheet P. The thermistor 64 in this embodiment is supported by a heater support 63, and is in contact with the upper surface of the heater 70 (the surface opposite to the surface of the heater 70 facing the pressure plate 62).

[0065] The heater support 63 supports the heater 70. The heater support 63 is made of a material such as liquid crystal polymer, which is a type of highly heat-resistant functional resin. The heater support 63 is supported by a metal stay 66. The pressure plate 62, the heater 70, the heater support 63, and the metal stay 66 form a moving unit (heater unit) that moves back and forth in the Z direction to approach and move away from the receiving plate 67. The metal stay 66 is a reinforcing member (rigidity member) that increases the rigidity of the moving unit.

[0066] The pressure lever 65 is fastened to a metal stay 66, and reciprocates in the Z direction by the driving force of the drive source. When the pressure lever 65 moves the moving unit downward, the pressure plate 62 comes into contact with the uppermost sheet of the sheet stack on the receiving plate 67. When the pressure lever 65 moves the moving unit upward, the pressure plate 62 moves away (retracts) from the sheet stack on the receiving plate 67.

[0067] The receiving plate 67 is a plate-shaped member made of silicone rubber having a thickness of, for example, 2.0 mm, and is supported by a frame (frame of the post-processing device 4) of the booklet producing device 50. The receiving plate 67 has a role of applying a stable pressure to the sheet stack by receiving the sheet stack pressed by the pressure lever 65.

[0068] The material of the receiving plate 67 is not limited to silicone rubber. In order to stably transmit pressure to the sheet stack, the material of the receiving plate 67 is preferably one that has a certain degree of deformability, an elastic modulus of 1000 Pa or less, is resistant to repeated stress, and is heat resistant.

[0069] The thermocompression bonding unit 60 performs a thermocompression bonding operation (adhesive operation) in which the sheet stack is pressurized and heated by the pressure plate 62. Specifically, in the thermocompression bonding operation, the pressure plate 62, which has been preheated to a target temperature, is pressed against the sheet stack for a predetermined time (e.g., 2 seconds), and then the pressure plate 62 is separated from the sheet stack. The sheet stack is heated by being sandwiched between the pressure plate 62 and the receiving plate 67, and is further heated by the pressure plate 62 heated by the heat of the heater 70. The thermocompression bonding operation softens the adhesive toner applied in advance by the printer unit 1, and the sheets are adhered to each other via the adhesive toner acting as an adhesive.

[0070] The booklet production apparatus 50 of this embodiment produces a booklet containing more than a predetermined number of sheets as a product by performing one thermocompression bonding operation in the thermocompression bonding unit 60 each time a predetermined number of sheets P are stacked. That is, the thermocompression bonding unit 60 performs the next thermocompression bonding operation in a state in which the subsequent sheets are stacked on top of the bonded sheet stack bonded in the previous thermocompression bonding operation, thereby bonding the surface (first surface) of the top sheet of the bonded sheet stack to the surface (second surface) of the subsequent sheet opposite the first surface. This allows the thermocompression bonding unit 60 to produce a booklet with a greater number of sheets than can be bonded in one thermocompression bonding operation.

[0071] The number of sheets P that the thermocompression bonding unit 60 thermocompresses in one thermocompression bonding operation (predetermined number) can be changed as appropriate, taking into consideration the time required for the thermocompression bonding process and the productivity of booklet production. The thermocompression bonding unit 60 may be configured to perform one thermocompression bonding operation every time one subsequent sheet is stacked on the bonded sheet stack. In the following description, it is assumed that the thermocompression bonding unit 60 performs one thermocompression bonding operation every time five sheets P are stacked on the intermediate stacking section 51.

[0072] For example, a booklet consisting of 50 sheets P is produced by the following process. The first thermocompression bonding operation is performed when the first to fifth sheets P are stacked on the intermediate stacker 51 and aligned by the alignment mechanism. By the first thermocompression bonding operation, a bonded sheet stack including five sheets P (hereinafter, referred to as a five-sheet temporary booklet) is produced. The second thermocompression bonding operation is performed when the sixth to tenth sheets P are stacked on top of the five-sheet temporary booklet and aligned by the alignment mechanism. By the second thermocompression bonding operation, a bonded sheet stack including ten sheets P (hereinafter referred to as a ten-sheet temporary booklet) is produced. The third thermocompression bonding operation is performed when the 11th to 15th sheets P are stacked on top of the 10-sheet temporary booklet and aligned by the alignment mechanism. By the third thermocompression bonding operation, a bonded sheet stack including 15 sheets P (hereinafter referred to as a 15-sheet temporary booklet) is produced. Similarly, five sheets P are stacked on the already bonded temporary booklet and aligned by the alignment mechanism, and one thermocompression bonding operation is performed. Then, by the tenth thermocompression bonding operation, a booklet containing 50 sheets P is completed as a product.

[0073] When the number of sheets P that have been stacked in advance in the buffer mechanism (stacking section) are transported to the booklet production device 50, the number of sheets P stacked by the buffer mechanism (stacking section) is set to be the same as the number of sheets P that the thermocompression bonding unit 60 thermocompresses in one thermocompression bonding operation. This makes it possible to shorten the time required to complete alignment of a predetermined number of sheets P compared to when the booklet production device 50 aligns a predetermined number of sheets P that are transported one by one, and therefore may shorten the interval between thermocompression bonding operations. This also makes it possible to improve the productivity of the post-processing device 4 as a whole.

[0074] Furthermore, when the number of sheets included in one booklet is less than a predetermined number, the thermocompression operation may be performed when all sheets P included in one booklet are stacked on the intermediate stacker 51 and aligned by the alignment mechanism.

[0075] The booklet produced by the thermocompression operation of thermocompression unit 60 is pushed toward booklet discharge port 40 (FIG. 1) by a booklet discharge guide provided in booklet production device 50. The booklet discharge guide stops after the leading edge of the booklet reaches booklet discharge roller pair 39, and returns to the standby position. Having received the booklet from the booklet discharge guide, booklet discharge roller pair 39 discharges the booklet from post-processing device 4 to lower discharge tray 34. This completes the series of operations for producing one booklet.

[0076] (Relative position of seat and heater) The positional relationship between the sheet P and the heater 70 of the thermocompression bonding unit 60 in the booklet production apparatus 50 will be described with reference to Fig. 4. The size of the sheet P used to produce the booklet can be arbitrarily selected by the user from a variety of sizes. Fig. 4 shows A4 size, B5 size, and A5 size as examples of selectable sizes.

[0077] In this embodiment, the positions of the vertical alignment reference plate 52 and the horizontal alignment reference plate 55 are fixed to preset positions regardless of the size of the sheet P. In other words, regardless of the size of the sheet P, the reference positions in the X direction and the Y direction during sheet alignment in the booklet production apparatus 50 are constant.

[0078] The thermocompression bonding unit 60 is disposed so as to thermocompress the end of the sheet P on the same side as the horizontal alignment reference plate 55, based on the positions of the vertical alignment reference plate 52 and the horizontal alignment reference plate 55. The heater 70 in this embodiment extends in the X direction over a length that includes the long side length (297 mm) of A4 size from the position of the vertical alignment reference plate 52, and is positioned at a predetermined position relative to the horizontal alignment reference plate 55. In this way, by setting the position and size of the heater 70 based on the positions of the vertical alignment reference plate 52 and the horizontal alignment reference plate 55, sheets of various sizes can be bonded more reliably.

[0079] (adhesion form) Examples of adhesion forms resulting from different application patterns of adhesive toner Tn will be described with reference to Figures 5(a) and (b). Figure 5(a) shows an adhesion form of a booklet by corner binding (corner binding), in which adhesive toner Tn is applied to the corners of sheets P to bond the corners. Figure 5(b) shows an adhesion form of a booklet by edge binding (long side binding), in which adhesive toner Tn is applied to the edge of the left long side of sheets P to bond the edges. Note that sheets may be adhered to each other at corners other than those shown in the figure, or may be adhered to each other at the edge of the short side of sheets P.

[0080] When producing a booklet including n sheets P, the printer unit 1 applies adhesive toner Tn in a predetermined adhesive region (adhesive portion) to both sides of each sheet P, except for the front side of the first sheet P which becomes the cover of the booklet, and the back side of the nth sheet P which becomes the back cover of the booklet. Then, the booklet producing device 50 of the post-processing device 4 repeats the thermocompression operation in the thermocompression bonding unit 60 every time a predetermined number of sheets P are loaded, thereby producing a booklet with n sheets P bonded together.

[0081] Although an example in which adhesive toner Tn is applied to both sides of each sheet P has been shown here, adhesive toner Tn may be applied to only one side of the sheet P. Generally, applying adhesive toner Tn to both sides of the sheet P allows the sheets to adhere to each other via a sufficient amount of adhesive toner Tn, resulting in stronger adhesion.

[0082] Whether the adhesive toner Tn is applied to one side or both sides can be appropriately selected in consideration of the performance of the booklet production device 50, the type of adhesive toner Tn or sheet P, the functions required of the booklet, etc. For example, in the case of a booklet to be a keepsake or when thick paper or a special sheet P is used for the front or back cover of the booklet, the adhesive toner Tn may be applied to both sides of the sheet P to obtain reliable adhesion. In the case of a booklet for simple, single use, the adhesive toner Tn may be applied to only one side of the sheet P.

[0083] (Adhesive strength) FIG. 6(a) shows the results of measuring the relationship between the toner amount (amount of toner for adhesion) of adhesive toner Tn and adhesive strength. The adhesive strength here is the value measured as the peak force when two thermocompression-bonded sheets P are peeled off as shown in FIG. 6(b). Since the adhesive strength between the sheets P also depends on the width of the adhesive region, the adhesive strength is shown as a numerical value per unit length of the adhesive region (the value obtained by dividing the above-mentioned peak force by the length of the adhesive region in the X direction; unit N / cm). The toner amount is the amount of toner measured before the adhesive toner Tn is fixed by the fixing device 6, and is expressed as the toner weight per unit area (unit mg / cm). 2 )

[0084] As shown in Fig. 6(a), the adhesive strength is proportional to the amount of toner. On the other hand, after considering the adhesive strength between sheets P required for the completed booklet, we determined that an adhesive strength of about 0.5 N / cm or more is sufficient for producing a booklet, because the sheets P will tear before the sheets peel off at the adhesive toner Tn layer.

[0085] The adhesive strength of 0.5 N / cm obtained in this study was confirmed using plain Office 70 (70g) paper manufactured by Canon Marketing Japan Inc. as the sheet P. Although the above adhesive strength was confirmed using several types of sheet P, it may vary depending on the type of sheet and the intended use of the finished product. The criteria for sufficient adhesion may vary, so adhesion may be evaluated based on values ​​other than 0.5 N / cm.

[0086] As shown in FIG. 6(a), the amount of adhesive toner Tn required to obtain an adhesive force of 0.5 N / cm or more is 0.6 mg / cm 2 That is, in the booklet producing apparatus 50 and the image forming apparatus 1S of this embodiment, the total amount of the toner particles was 0.6 mg / cm on one or both of the opposing surfaces of the sheets P to be bonded. 2 If the adhesive toner Tn is applied in this amount, sufficient adhesive strength can be obtained.

[0087] (Toner adhesion to pressure plate) Next, a phenomenon that occurs when a booklet is produced will be described. As described above, by applying adhesive toner Tn to the opposing surfaces of sheets to be bonded together, the adhesive strength can be increased compared to the case where adhesive toner Tn is applied only to one of the surfaces. However, when a booklet is produced as a final product by repeatedly applying heat and pressure with the pressure plate 62, the pressure plate 62 may come into contact with the adhesive toner Tn applied to the surface of the sheet stack (provisional booklet) in the middle of production, and a part of the adhesive toner Tn may adhere to the pressure plate 62. Then, the adhesive toner Tn may be transferred from the pressure plate 62 to a sheet that is to be the front or back cover of the booklet, causing a stain, which may reduce the quality of the completed booklet.

[0088] A specific description will be given with reference to Figures 7(a)-(c) and Figures 8(a)-(c). Here, a booklet containing 50 sheets is produced by repeating one thermocompression operation every time five sheets P are stacked. In the following description, the "front surface" of each sheet P refers to the surface (upward surface) of the sheet P facing the pressure plate 62, and the "back surface" refers to the surface (downward surface) of the sheet P facing the receiving plate 67.

[0089] FIG. 7(a) is a schematic diagram showing the first to fifth sheets P1 to P5. The adhesive toner Tn is not applied to the back surface P1b of the first sheet P1. This is because the back surface P1b of the first sheet P1 is the surface that will become the cover of the completed booklet and is not attached to other sheets of the booklet. The front surface P1a of the first sheet P1 is the surface that will be attached to the back surface P2b of the second sheet P2, so the adhesive toner Tn is applied to the front surface P1a. The adhesive toner Tn is applied to both the front surface and the back surface of each of the second to fifth sheets P2 to P5. In the first thermocompression operation, the first to fifth sheets P1 to P5 are heated and pressed by the pressure plate 62, and a temporary booklet (a five-sheet temporary booklet) including the five sheets P1 to P5 is produced.

[0090] FIG. 7(b) is a schematic diagram showing the sixth to tenth sheets P6 to P10. The sixth to tenth sheets P6 to P10 have adhesive toner Tn applied to both the front and back sides. That is, unlike the first sheet P1, the back side P6b of the sixth sheet P6 is the surface to be adhered to the front side P5a of the fifth sheet P5 (the upper surface of the five-sheet temporary booklet), and is therefore coated with adhesive toner Tn. In the second thermocompression operation, the sixth to tenth sheets P6 to P10 stacked on the already adhered five-sheet temporary booklet are heated and pressed by the pressure plate 62, and a temporary booklet including ten sheets P1 to P10 (ten-sheet temporary booklet) is produced.

[0091] Thereafter, in the same manner, the already bonded temporary booklet and the succeeding sheets stacked on the temporary booklet are heated and pressed by the pressure plate 62, whereby a new temporary booklet is produced.

[0092] 7(c) is a schematic diagram showing the 46th to 50th sheets P46 to P50 to be thermocompression bonded in the 10th thermocompression bonding operation (the final thermocompression bonding operation). The adhesive toner Tn is not applied to the front P50a of the 50th sheet P50. This is because the front P50a of the 50th sheet P50 is the surface that will become the back cover (rear cover) of the completed booklet and is not to be bonded to other sheets of the booklet. The back P50b of the 50th sheet P50 is to be bonded to the front P49a of the 49th sheet P49, and therefore the adhesive toner Tn is applied to it. The 46th to 49th sheets P46 to P49 have the adhesive toner Tn applied to both the front and back surfaces. In the tenth thermocompression operation, the 46th to 50th sheets P46 to P50, which are stacked on top of the already bonded 45-sheet temporary booklet, are heated and pressed by the pressure plate 62, completing the creation of a booklet containing 50 sheets P1 to P50.

[0093] Here, when the temporary booklet is produced, adhesive toner Tn is applied to the surface of the top sheet of the temporary booklet. Specifically, as shown in Fig. 7(a) and Fig. 8(a), adhesive toner Tn is applied to the surface P5a of the fifth sheet P5, which is the top sheet of the five-sheet temporary booklet.

[0094] Therefore, as shown in Fig. 8(b), during the first thermocompression bonding operation, the pressure plate 62 comes into contact with the adhesive toner Tn exposed on the upper surface (surface P5a) ​​of the five-sheet temporary booklet. Then, as shown in Fig. 8(c), when the pressure plate 62 is separated from the five-sheet temporary booklet after the thermocompression bonding operation, some of the adhesive toner Tn may adhere to the pressure plate 62.

[0095] The adhesive toner Tn adhered to the pressure plate 62 comes into contact with the surface P10a (FIG. 7(b)) of the tenth sheet P10 in the second thermocompression operation. However, since the adhesive toner Tn is applied to the surface P10a of the tenth sheet P10, the adhesive toner Tn adhered to the pressure plate 62 does not stain the completed booklet. Similarly, in the third to ninth thermocompression operations, the adhesive toner Tn adhered to the pressure plate 62 does not stain the completed booklet.

[0096] However, in the final thermocompression operation, the pressure plate 62 comes into contact with the surface P50a (FIG. 7(c)) of the 50th sheet P50 on which the adhesive toner Tn is not applied. Therefore, if the adhesive toner Tn that has adhered to the pressure plate 62 in the first to ninth thermocompression operations is transferred from the pressure plate 62 to the surface P50a of the 50th sheet P50 in the final thermocompression operation, it will cause stains on the back cover of the completed booklet.

[0097] In this way, there was a possibility that the adhesive toner Tn that adhered to the pressure plate 62 during the thermocompression operation during the production of the booklet would adhere to the sheet that would become the outer surface (front or back cover) of the completed booklet in the final thermocompression operation, thereby reducing the quality of the completed booklet.

[0098] If a colored toner similar to the image toner is used as the adhesive toner Tn, when the adhesive toner Tn is transferred to the outer surface of the finished booklet, it becomes apparent as colored stains. Even if a colorless or white toner is used as the adhesive toner Tn, the adhesive toner Tn may harden in a state where foreign matter such as paper powder or dust is mixed in, or there may be a difference in gloss from the surrounding area, which may cause stains to become apparent.

[0099] (Amount of Adhered Toner on the Facing Surface of Sheets) Incidentally, if adhesive toner Tn is not applied to the surface P5a of the fifth sheet P5, the surface P10a of the tenth sheet P10, etc., with which the pressure plate 62 comes into contact, it is possible to prevent the toner from adhering to the pressure plate 62. However, since the adhesive force decreases as the amount of adhesive toner Tn decreases, there is a possibility that the adhesive force of the fifth and sixth sheets P5 and P6, for example, will become insufficient.

[0100] It is also possible to obtain sufficient adhesive strength by increasing the amount of adhesive toner Tn on the back surface P6b of the sixth sheet P6 without applying adhesive toner Tn on the front surface P5a of the fifth sheet P5. For example, the amount of adhesive toner Tn on other sheets is set to 0.3 mg / cm 2 The back surface P6b of the sixth sheet P6 has twice the toner amount of 0.6 mg / cm 2It is possible to apply adhesive toner Tn with

[0101] However, in a single process cartridge 7n, the 2 It may be difficult to develop a toner image with such an amount of toner. In addition, in order to increase the amount of toner, it is possible to overlap toner images developed using a plurality of cartridges on the sheet P, but this would require arranging a plurality of process cartridges 7n using adhesive toner, which may lead to an increase in size and complexity of the image forming apparatus 1S.

[0102] Therefore, in this embodiment, the amount of adhesive toner Tn applied to the surface (first surface) of the sheet P that contacts the pressure plate 62 during the production of the booklet is made smaller than the amount of adhesive toner Tn applied to the surface (second surface) of the sheet opposite to the first surface. In other words, in this embodiment, the amount of adhesive toner applied to the first surface by the image forming means is smaller than the amount of adhesive toner applied to the second surface by the image forming means. The first surface here refers to the surface of the top sheet of the sheet stack that has been bonded in the previous bonding operation, and the second surface refers to the surface of the subsequent sheet that is to be bonded to the first surface. This configuration can reduce the possibility that the adhesive toner Tn that has adhered to the pressure plate 62 during the thermocompression operation during the production of the booklet will stain the completed booklet.

[0103] The effect on adhesive strength was confirmed when the amount of adhesive toner Tn applied to the opposing surfaces (opposing surfaces) of two sheets P to be adhered was varied. Figure 9 shows the results of confirming adhesive strength under different conditions of the magnitude relationship between the amount M1 of adhesive toner Tn applied to the surface (first surface) of one sheet P and the amount M2 of adhesive toner Tn applied to the surface (second surface) of the other sheet P to be adhered to the first surface. The adhesive strength was measured in the same manner as described using Figures 6(a) and (b). The horizontal axis of Figure 9 is the sum of the amounts M1 and M2 of adhesive toner Tn on the first and second surfaces.

[0104] As shown in Fig. 9, it was found that the magnitude of the adhesive force is mainly determined by the sum of the amounts M1 and M2 of the adhesive toner Tn on the first and second sides. On the other hand, whether more adhesive toner Tn is applied to the first or second side does not have much effect on the magnitude of the adhesive force.

[0105] Therefore, it is preferable to reduce the amount of adhesive toner Tn applied to the surface (first surface) of the sheet P that comes into contact with the pressure plate 62 during the production of the booklet, and to increase the amount of adhesive toner Tn applied to the surface (second surface) of the sheet P opposite the first surface. Specifically, it is preferable that the total amount of adhesive toner Tn applied to the first and second surfaces is equal to or greater than the total amount of adhesive toner Tn applied to the opposing surfaces of the sheets P that do not come into contact with the pressure plate 62. In this embodiment, 0.3 mg / cm is applied to the opposing surfaces of the sheets P that do not come into contact with the pressure plate 62. 2 Since adhesive toner Tn is applied to the first and second surfaces, the total amount of adhesive toner Tn applied to the first and second surfaces is also 0.6 mg / cm 2 In other words, in this embodiment, the total amount of adhesive toner applied to the first surface and the second surface is preferably 0.6 mg / cm. 2 In addition, the total amount of adhesive toner applied to the opposing surfaces of two adjacent sheets in the product other than the first surface and the second surface is 0.6 mg / cm 2 That's all.

[0106] Furthermore, when the amount of adhesive toner Tn on the first surface is reduced and the amount of adhesive toner Tn on the second surface is increased, it is preferable that the sheets P are bonded together with sufficient adhesive force. In other words, it is preferable that the adhesive force between the sheets whose first and second surfaces are bonded together is 0.5 N / cm or more. It is also preferable that the adhesive force between the sheets whose opposing surfaces of two adjacent sheets in the product are bonded together other than the first and second surfaces is 0.5 N / cm or more. By setting the amount of adhesive toner that the printer unit 1 applies to each sheet according to the characteristics of the adhesive toner Tn so as to obtain such adhesive force, sufficient adhesive force can be obtained in the booklet that is the product.

[0107] As mentioned above, there is an upper limit to the amount of toner that can be developed by a single process cartridge 7n. In the process cartridge 7n of this embodiment, the upper limit is about 0.5 mg / cm 2 In this case, the amount of adhesive toner Tn applied to the second surface is 0.5 mg / cm 2 The total amount of adhesive toner Tn applied to the first and second sides is set to 0.6 mg / cm 2 This makes it possible to reduce the possibility that the adhesive toner Tn adhering to the pressure plate 62 during the thermocompression operation during the production of the booklet will stain the finished booklet, while avoiding an increase in size and complexity of the image forming apparatus 1S.

[0108] The upper limit of the toner amount of a toner image that can be developed by a single process cartridge 7n can vary depending on various conditions related to the development process. These conditions include the types and outer diameters of the photosensitive drum, developing roller, developing blade, etc., the properties of the toner, the potential of the electrostatic latent image formed on the photosensitive drum, and the potential settings of the photosensitive drum, developing roller, and developing blade. In addition, the upper limit of the toner amount is 0.5 mg / cm2, which is given as an example. 2 is described as the value of the toner amount that can be secured regardless of conditions that vary depending on the user, such as the usage environment, usage state, and sheets used, of the image forming apparatus 1S.

[0109] Next, the amount of adhesive toner Tn applied to the surface (first surface) of sheet P that comes into contact with pressure plate 62 during the production of the booklet and the surface (second surface) of sheet P opposite to the first surface was changed, and the presence or absence of stains on the completed booklet was confirmed. Figure 10 shows the results of confirming the adhesive strength of the completed booklet and the adhesion of adhesive toner Tn to the back cover of the booklet when a booklet containing 50 sheets P was produced as described using Figures 7(a) to (c). The confirmation was performed by repeating the production of the booklet multiple times and evaluating the adhesive strength and the degree of toner adhesion to the back cover.

[0110] The horizontal axis in Fig. 10 represents the amount M1 of the adhesive toner Tn applied to the surface of the 5n-th sheet P (n = 1, 2, …, 9), which is an example of the surface (the first surface) of the sheet P that contacts the pressure plate 62 during the production of the booklet. The vertical axis in Fig. 10 represents the amount M2 of the adhesive toner Tn applied to the back surface of the (5n + 1)-th sheet P, which is an example of the surface (the second surface) adhered to the first surface.

[0111] The meaning of the symbols in Fig. 10 will be explained. The symbol “〇” indicates that no toner adhesion to the front and back covers of the completed booklet was confirmed. The symbol “●” indicates that although there is toner adhesion at a level that is not easily visible, it was determined to be at a level that does not pose a problem. The symbol “ △” indicates that there is toner adhesion at a visible level and it may pose a problem. The symbol “×” indicates that the toner adhesion is at a level where it can be immediately visually recognized.

[0112] Also, in Fig. 10, the area above and to the right of the hatched area indicates that the total amount of the adhesive toner Tn applied to the opposing surfaces of the sheets P is large, and sufficient adhesive force (0.5 N / cm or more) can be obtained in the completed booklet. The area below and to the left of the hatched area indicates that the total amount of the adhesive toner Tn applied to the opposing surfaces of the sheets P is small, resulting in an adhesive force of less than 0.5 N / cm. Inside the hatched area, both cases where the adhesive force is 0.5 N / cm or more and less than 0.5 N / cm exist.

[0113] As shown in Fig. 10, by making the toner amount M1 on the surface of the 5n-th sheet P that contacts the pressure plate 62 during the production of the booklet less than the toner amount M2 on the back surface of the (5n + 1)-th sheet P, which is the opposing surface (M1 < M2), the toner adhesion to the back cover of the booklet was reduced. That is, it was confirmed that the stain on the booklet can be reduced by making the amount of the adhesive toner Tn applied to the surface (the first surface) of the sheet P that contacts the pressure plate 62 during the production of the booklet less than the amount of the adhesive toner Tn applied to the surface (the second surface) of the sheet P adhered to the first surface.

[0114] Also, while maintaining the relationship M1 < M2, by setting the amounts M1 and M2 of the adhesive toner Tn such that the sum of M1 and M2 is about 0.6 mg / cm 2 or more, it was confirmed that sufficient adhesive force can be obtained while reducing the soiling of the booklet. Note that since the criteria for sufficient adhesive force can vary depending on the use of the product as described above, even if the sum of M1 and M2 is about 0.6 mg / cm 2 even so, due to the relationship M1 < M2, at least a product with reduced soiling can be obtained.

[0115] On the other hand, it was confirmed that when the toner amount M1 on the surface of the 5n-th sheet P is made larger than the toner amount M2 on the back surface of the 5n + 1-th sheet P which is the opposite surface (M1 > M2), toner adhesion to the back cover of the booklet is likely to occur. Also, although sufficient adhesive force can be obtained by setting the amounts M1 and M2 of the adhesive toner Tn such that the sum of M1 and M2 is about 0.6 mg / cm 2 or more, there was a case (×) where visible soiling adhered to the back cover of the completed booklet.

[0116] From the above results, for example, the toner amount M1 on the surface of the 5n-th sheet P that comes into contact with the pressure plate 62 during the production of the booklet is set to 0.2 mg / cm 2 and the toner amount M2 on the back surface of the 5n + 1-th sheet P which is the opposite surface is set to 0.4 mg / cm 2 for example, which is preferable. Thereby, sufficient adhesive force can be obtained while reducing the soiling of the booklet.

[0117] Thus, the adhesion means of this embodiment performs the next adhesion operation with the subsequent sheet loaded on the bonded sheet bundle bonded in the previous adhesion operation, thereby bonding the first surface of the topmost sheet of the bonded sheet bundle and the second surface of the subsequent sheet facing the first surface. Thereby, a product obtained by bonding a number of sheets larger than the number of sheets that can be bonded in one adhesion operation can be produced.

[0118] The amount of adhesive toner applied to the first surface by the image forming means is less than the amount of adhesive toner applied to the second surface by the image forming means. This makes it possible to suppress adhesion of adhesive toner to the heating and pressurizing member in the bonding operation during the production of the final product, and to reduce the possibility that the adhesive toner attached to the heating and pressurizing member will transfer to the outer surface of the final product and cause stains in the final bonding operation.

[0119] In this way, in this embodiment, in order to reduce stains on the product, the amount of adhesive toner applied to the first surface of a sheet and the amount of adhesive toner applied to the second surface of a subsequent sheet that is adhered to the first surface can be changed. In other words, according to this embodiment, the amount of toner in the adhesive portion can be changed as needed. In other words, according to this embodiment, it is possible to provide an image forming apparatus that can improve the quality of a sheet stack.

[0120] (Modification) In the first embodiment, the amount of adhesive toner Tn applied to the surface of the sheet P other than the surface (first surface) of the sheet P that contacts the pressure plate 62 during the production of the booklet and the surface (second surface) of the sheet P opposite to the first surface is constant (for example, 0.3 mg / cm 2 ). As a modified example, the amount of adhesive toner Tn applied to the front surface, which is the surface facing the pressure plate 62, of all sheets P included in the completed booklet may be made smaller than the amount of adhesive toner Tn applied to the back surface, which is the surface not facing the pressure plate 62. Here, the "surface facing the pressure plate 62" refers to the side of each sheet P facing the pressure plate 62 in FIG. 8(a), that is, the upper surface in the figure, and the "surface not facing the pressure plate 62" refers to the lower surface of each sheet P in the figure.

[0121] In other words, in this modification, the amount of adhesive toner that the image forming means applies to the surface of each sheet facing the pressure member is less than the amount of adhesive toner that the image forming means applies to the surface of each sheet opposite the facing surface. In other words, according to this modification, the amount of toner in the adhesive portion can be changed as needed.

[0122] Since the amount of adhesive toner Tn on the front side of each sheet P is less than the amount of adhesive toner Tn on the back side, the amount of adhesive toner Tn on the surface (first surface) of the sheet P that comes into contact with the pressure plate 62 during the production of the booklet is also less than the amount of adhesive toner Tn on the surface (second surface) of the sheet P opposite to the first surface. Therefore, in this modified example as well, it is possible to reduce stains on the completed booklet, similar to the first embodiment.

[0123] In addition, this modified example has the following unique advantages. In most cases, the sheet P used to produce a booklet is the sheet P stored in the cassette 8 of the printer unit 1, and the temperature of the sheet P at the start of the image forming operation is close to the temperature (room temperature) of the installation environment in which the printer unit 1 is placed. After the toner image of the image toner and the adhesive toner is transferred to such a sheet P, the fixing process is performed in the fixing device 6, and the temperature of the sheet P rises. In the fixing process, heat required to melt the toner image is applied to the sheet P, depending on the type and amount of toner. Therefore, in the fixing process, the temperature of the sheet P rises from a temperature close to room temperature to 80°C to 120°C. When the temperature of the sheet P rises suddenly in the fixing process in this way, the sheet P may curl.

[0124] The mechanism by which curling occurs will be explained. Sheet P contains moisture, and the amount of moisture varies depending on the temperature and humidity of the environment in which the printer unit 1 is mounted and the material of sheet P. In the fixing process, some of the moisture contained in sheet P evaporates as water vapor. However, the amount of moisture that evaporates differs between the front and back sides of sheet P. Sheet P curls when the difference in the amount of moisture that evaporates causes a difference in the amount of shrinkage between the front and back sides of sheet P, causing sheet P to curl with the side that has shrunk more inward.

[0125] In the fixing process for the front side of the sheet P, the temperature of the sheet P rises rapidly from a temperature close to room temperature to the fixing temperature, which tends to increase the difference in the amount of moisture evaporated from the front side and back side of the sheet P. In other words, in the fixing process for the front side of the sheet P, curling also tends to increase.

[0126] By reducing the amount of adhesive toner Tn applied to the surface of the sheet P, sufficient fixability can be obtained even if the amount of heat applied to the sheet P in the fixing process of the surface of the sheet P is reduced. Therefore, by reducing the amount of heat applied to the sheet P in the fixing process of the surface of the sheet P, the occurrence of curling can be reduced.

[0127] On the other hand, in the fixing process for the back surface of the sheet P, the moisture content of the sheet P is reduced in the fixing process for the front surface, and the amount of newly evaporated moisture is small, so the difference in the amount of moisture evaporated from the front surface and back surface of the sheet P is also small. Also, since the temperature of the sheet P is increased to some extent in the fixing process for the front surface, the amount of heat applied to the sheet P in the fixing process for the back surface may be less than that in the fixing process for the front surface. Therefore, even if the amount of adhesive toner Tn applied to the back surface of the sheet P is increased, a large curl is unlikely to occur.

[0128] In this manner, in this modified example, the amount of adhesive toner Tn applied to the front surface of all sheets P included in the completed booklet is made less than the amount of adhesive toner Tn applied to the back surface, thereby suppressing curling. This makes it easier to align the sheets P in the booklet producing device 50, and makes it possible to produce a booklet with good sheet alignment.

[0129] (Other variations) In Example 1, the example of producing a booklet by edge-stitching (long-edge binding) the sheets together has been described, but the same effect as in Example 1 can be obtained even when producing a booklet by corner-stitching the sheets together.

[0130] In the first embodiment, an example has been described in which the surface of the sheet on which the toner image is formed first in the printer unit 1 is the surface facing the pressure plate 62 in the booklet production device 50, and the surface of the sheet on which the toner image is formed later is the surface that does not face the pressure plate 62 in the booklet production device 50. However, a configuration may also be used in which the surface of the sheet on which the toner image is formed first in the printer unit 1 is the surface that does not face the pressure plate 62 in the booklet production device 50, and the surface of the sheet on which the toner image is formed later is the surface that faces the pressure plate 62 in the booklet production device 50. Even in this case, the same effect as in the first embodiment can be obtained by making the amount of adhesive toner Tn applied to the surface of the sheet that contacts the pressure plate 62 (first surface) less than the amount of adhesive toner Tn applied to the surface of the sheet that faces the first surface (second surface).

[0131] Example 2 As the second embodiment, a configuration in which one type of toner is used both as the image toner and the adhesive toner will be described. By using one type of toner both as the image toner and the adhesive toner, it becomes possible to relatively easily add the adhesive function of the sheet by reusing the configuration of a monochrome image forming device. In addition, in the second embodiment, a configuration in which the amount of toner is made different between the image area and the adhesive area on the sheet will be described. Note that, also in the first embodiment, the adhesive toner Tn may be colored black, and black may be expressed by the adhesive toner Tn instead of process black. In this case, not only can the adhesive function of the sheet be added by reusing the configuration of a color image forming device, but there is also the advantage that the amount of toner consumed when expressing black can be reduced.

[0132] In the following, elements having the same reference symbols as those in Example 1 will be assumed to have substantially the same configurations and functions as those described in Example 1, unless otherwise specified, and the following will mainly describe the parts that differ from Example 1.

[0133] (Overall configuration of image forming apparatus) 12 is a schematic diagram of an image forming apparatus 200S according to Example 2. The image forming apparatus 200S includes a printer section 200 having an image forming unit 1e, an intermediate conveyance unit 26, and a post-processing device 4.

[0134] The image forming unit 1e of this embodiment is a direct transfer type electrophotographic unit including one process cartridge 7n (within the frame of the thick dashed line), a scanner unit 2, and a transfer unit 208 (transfer roller). The process cartridge 7n includes a photosensitive drum Dn as an image carrier, a charging roller 201, and a developing unit. The charging roller 201 functions as a charging means for charging the photosensitive drum Dn. The developing unit includes a toner storage section 202 that stores toner Tnbk as a developer, a developing roller 205 as a developer carrier that carries the toner, and a supply member 204 that supplies toner to the developing roller 205. The developing unit further includes an agitating member 203 that agitates the toner Tnbk, and a regulating member 206 (developing blade) that regulates the amount of toner Tnbk carried by the developing roller 205.

[0135] The process cartridge 7n creates a visible image using colored toner Tnbk, and also creates a toner image for applying the toner Tnbk to a sheet P in a predetermined adhesion pattern. In this embodiment, the toner Tnbk is colored black. The toner image created on the photosensitive drum Dn in the process cartridge 7n is transferred from the photosensitive drum Dn to the sheet P by the transfer unit 208 in the transfer nip 5n.

[0136] In addition to the black process cartridge 7n, three process cartridges, yellow, magenta, and cyan, may be arranged to form a color image forming apparatus. Yellow toner may also be used as adhesive toner. In this case, the area where the adhesive toner is applied becomes difficult to see, and the texture of the finished product can be improved. Not limited to this, the type and number of toners can be changed depending on the use of the image forming apparatus 200S.

[0137] In the process cartridge 7n, the photosensitive drum Dn, the charging roller 201, and the developing unit may be arranged in one unit. Alternatively, in the process cartridge 7n, for example, the photosensitive drum Dn and the charging roller 201 may be arranged in a unit (drum unit) separate from the developing unit, and each unit may be independently attachable to and detachable from the housing 19.

[0138] In this embodiment, when a print instruction accompanied by image data is input, controller 107, which will be described later, causes image forming unit 1e to create a toner image (hereinafter referred to as a normal image) based on the image data in a predetermined area on sheet P. Furthermore, when the print instruction includes a setting for producing a product in which sheets P are adhered to each other in booklet producing device 50, controller 107 adds additional data to the image data for applying toner Tnbk in a predetermined adhesion pattern to sheet P. Then, controller 107 causes image forming unit 1e to create a toner image (hereinafter referred to as an adhesive toner image) based on the additional data.

[0139] Hereinafter, the area on the photosensitive drum Dn where the toner image for forming the normal image on the sheet P is created is referred to as the "image area". Also, the area on the photosensitive drum Dn where the toner image for forming the adhesive toner image on the sheet P is created is referred to as the "adhesive area". In this embodiment, the image area and the adhesive area are areas separated from each other in the main scanning direction of the scanner unit 2. That is, the toner for adhesion in this embodiment is the same as the toner used to create the image in the image area. Also, the image forming means in this embodiment forms an adhesive toner image in the adhesive area on the sheet using the toner, and forms an image in an image area different from the adhesive area on the sheet using the toner. Also, hereinafter, the area on the sheet P corresponding to the image area on the photosensitive drum Dn is also referred to as the "image area" of the sheet P, and the area on the sheet P corresponding to the adhesive area on the photosensitive drum Dn is also referred to as the "adhesive area" of the sheet P.

[0140] (Scanner unit) The following describes the laser drive circuit mounted on the scanner unit 2. FIG.

[0141] The scanner unit 2 is an example of an exposure unit that forms an electrostatic latent image by irradiating light onto the photosensitive drum Dn to expose it. The scanner unit 2 includes a semiconductor laser 100, a polygon mirror 101, a synchronization sensor 102, and a laser driving circuit 207. The laser driving circuit 207 includes a light emission control unit 103, a driving current generation unit 104, and a correction current generation unit 105.

[0142] The CPU 106 of this embodiment performs serial communication with the drive current generation unit 104 and the correction current generation unit 105 via a serial communication signal 110. The drive current generation unit 104 outputs a laser drive current amount signal 111 based on information transmitted from the CPU 106, and controls the amount of current of the laser drive current 112. The correction current generation unit 105 outputs a correction current amount signal 113 based on current amount information at the main scanning position transmitted from the CPU 106, in synchronization with a main scanning synchronization signal 108. The laser drive current 112 is controlled to an amount of current obtained by subtracting the amount of current based on the correction current amount signal 113 from the amount of current based on the laser drive current amount signal 111.

[0143] For this reason, in this embodiment, the amount of laser light irradiated from the scanner unit 2 to the photosensitive drum Dn varies depending on the position in the main scanning direction.

[0144] In addition, the image signal 109 sent from the controller 107 is generated based on data for creating a normal image (image data input together with a print instruction) to which additional data for creating an adhesive toner image has been added.

[0145] (Adhesive Toner) The toner Tnbk of this embodiment may be a toner containing a thermoplastic resin and a colorant. The resin that may be used for the thermoplastic resin is not particularly limited, and may be a polyester resin, a vinyl resin, an acrylic resin, a styrene-acrylic resin, or the like, which is the same as that used in known image toners. A plurality of these resins may be included. The toner Tnbk may also contain a magnetic material, a charge control agent, a wax, an external additive, or the like.

[0146] In this embodiment, the toner Tnbk is colored black. When the image forming apparatus 200S is used as a color image forming apparatus, the toner Tnbk may be colored in other colors such as yellow, magenta, cyan, etc. When the image forming apparatus 200S is used as a single-function sheet bonding apparatus that does not normally create images and has only a bonding function, the toner Tnbk may be a transparent toner without being colored.

[0147] (Exposure Control) The exposure control of the scanner unit 2 will be described with reference to Figures 15(a) and (b). In the following, it is assumed that adhesive toner images are formed on the edges of the long sides of both sides of each sheet P, except for the sides that will become the front and back covers of the booklet, as shown in Figure 5(b).

[0148] 15(a) shows the amount of exposure light for each position in the main scanning direction when an adhesive toner image and a normal image are formed on the rear surface of a sheet P. The laser driving current 112 is Ir when the value of the laser driving current signal 111 is Vr [V] and the value of the correction current signal 113 is 0 [V]. When the value of the laser driving current signal 111 is Vr and the value of the correction current signal 113 is Vc [V], the laser driving current 112 is a value (Ir-Ic) smaller than Ir. The correction current signal 113 changes from 0 [V] to Vc after a predetermined time based on the falling edge of the main scanning synchronization signal 108.

[0149] While the image signal 109 is at High, a laser drive current 112 flows through the semiconductor laser 100. Therefore, during the period when the image signal 109 is at High, a current of Ir flows through the semiconductor laser 100 in a section where the value of the correction current amount signal 113 is 0, and a current of (Ir-Ic) flows through the semiconductor laser 100 in a section where the value of the correction current amount signal 113 is Vc.

[0150] The section where the value of the correction current amount signal 113 is 0 corresponds to the adhesive area on the photosensitive drum Dn, and the section where the value of the correction current amount signal 113 is Vc corresponds to the image area on the photosensitive drum Dn. Therefore, the exposure light amount of the scanning light L3 irradiated onto the photosensitive drum Dn from the semiconductor laser 100 via the polygon mirror 101 (FIG. 14) is the light amount Rr (μJ / cm) corresponding to the current amount Ir when scanning the adhesive area. 2 ). The exposure light amount of the scanning light L3 is the light amount Rt (μJ / cm2) corresponding to the current amount (Ir-Ic) when scanning the image area. 2 )

[0151] In this way, the width of the adhesive area can be set by the output timing of the image signal 109 and the correction current amount signal 113. Also, by changing the voltage Vr of the laser drive current amount signal 111 and the voltage Vc of the correction current amount signal 113, it is possible to change the amount of exposure light in the image area and the adhesive area. The image signal 109 always outputs High during the period when the adhesive area is scanned in order to form an adhesive toner image on the back surface of the sheet P. The exposure light amount of the scanning light L3 is light amount Rt in the image area, and light amount Rr higher than light amount Rt in the adhesive area.

[0152] The controller 107 that outputs the image signal 109 and the correction current generation unit 105 that outputs the correction current amount signal 113 are examples of the light amount correction means for correcting the light amount of the scanning light L3 emitted by the exposure device. Rr is the light amount when scanning the area on the photosensitive drum Dn corresponding to the adhesion area on the back surface (second surface) of the sheet P facing the surface (first surface) of the sheet P that contacts the pressure plate 62 during production with the scanning light L3. Rrf is the light amount when scanning the area on the photosensitive drum Dn corresponding to the image area on the second surface with the scanning light L3. The controller 107 and correction in this embodiment correct the light amount of the scanning light L3 according to the position in the main scanning direction so that Rr > Rgr. Thereby, the magnitude relationship (Mr < Mgr) of the toner amounts between the adhesion area and the image area can be realized.

[0153] In this way, in this embodiment, by changing the light amount during exposure, the toner amount per unit area (toner loading amount) in the adhesion area on the sheet and the toner amount per unit area (toner loading amount) in the image area can be changed. That is, according to this embodiment, the toner amount of the adhesion part can be changed as needed. Thereby, while setting the toner amount that results in good image density and toner consumption in the image area, the toner amount in the adhesion area can be set independently of the image area based on other indicators such as reducing the adhesion force between sheets and the contamination of the product.

[0154] Note that the toner amount in the image area is based on the toner amount of the image formed on the sheet P when image data of a solid-filled image (so-called solid black) with a density of 100% is input to the image forming apparatus 200S.

[0155] Figure 15(b) shows the exposure light amount for each position in the main scanning direction when forming an adhesive toner image and a normal image on the surface of sheet P. The image signal 109 outputs a PWM signal (pulse width modulation signal) that becomes a density Dh lower than 100% during the period of scanning the adhesive area (the dot area in the figure) in order to form an adhesive toner image on the surface of sheet P. The laser drive current 112 repeats ON / OFF according to the image signal 109 with density Dh. The exposure light amount of the scanning light L3 is such that the light amount in the image area is Rt, and the light amount in the adhesive area is a light amount Rf (μJ / cm 2 ).

[0156] The controller 107 that outputs the image signal 109 is an example of a light amount correction means for correcting the light amount of the scanning light L3 emitted by the exposure device. Rf is the light amount when scanning the area on the photosensitive drum Dn corresponding to the adhesive area on the surface (first surface) of the sheet P that comes into contact with the pressure plate 62 during production with the scanning light L3. Rgf is the light amount when scanning the area on the photosensitive drum Dn corresponding to the image area on the first surface with the scanning light L3. The controller 107 of this embodiment corrects the light amount of the scanning light L3 according to the position in the main scanning direction so that Rf < Rgf. Thereby, the magnitude relationship (Mf < Mgf) of the toner amounts between the adhesive area and the image area can be realized.

[0157] (Toner amounts of normal image / adhesive toner image on front / back surfaces) In this embodiment, the relationship between the toner amounts of the normal image and the adhesive toner image formed on each of the front and back surfaces of each sheet P will be described with reference to FIG. 16. FIG. 16 is a schematic diagram of a sheet P on which a normal image and an adhesive toner image are formed by the printer unit 200 of this embodiment.

[0158] As in the first embodiment, the surface of the sheet P facing the pressure plate 62 in the booklet production apparatus 50 is referred to as the "front surface," and the surface opposite the front surface (the surface of the sheet P not facing the pressure plate 62) is referred to as the "back surface" of the sheet P. The toner amount in the image area of ​​the front surface of the sheet P is represented as Mgf, the toner amount in the adhesive area of ​​the front surface is represented as Mf, the toner amount in the image area of ​​the back surface is represented as Mgr, and the toner amount in the adhesive area of ​​the back surface is represented as Mr. Each toner amount is the amount of toner Tnbk before being subjected to the fixing process in the fixing device 6, and is expressed as the toner weight per unit area (unit: mg / cm). 2 )

[0159] As in the first embodiment, a method of making a difference between the toner amount Mf in the adhesion area on the front side and the toner amount Mr in the adhesion area on the back side can be considered to change the toner amount uniformly over the entire area in the main scanning direction on the photosensitive drum Dn. Specifically, there is a method of increasing or decreasing the amount of toner carried on the development roller 205 by controlling the regulating member 206 or the supply member 204, or a method of increasing or decreasing the amount of toner developed on the photosensitive drum Dn by controlling the peripheral speed difference between the photosensitive drum Dn and the development roller 205. However, these methods increase or decrease not only the toner amounts Mf and Mr in the adhesion area, but also the toner amounts Mgf and Mgr in the image area. In other words, these methods can increase or decrease the toner amount according to the position in the sub-scanning direction of the scanner unit 2, but cannot change the toner amount according to the position in the main scanning direction.

[0160] As described in the section of (exposure control), by controlling the correction current amount signal 113 output to the scanner unit 2, the exposure light amount can be changed according to the position in the main scanning direction. As a result, the toner amount can be changed according to the position in the main scanning direction at the same position in the sub-scanning direction, that is, between the adhesion area and the image area. Specifically, as shown in FIG. 16, on the surface of the sheet P, the toner amount Mf in the adhesion area can be made less than the toner amount Mgf in the image area (Mf < Mgf). Thereby, while reducing the soiling of the booklet due to toner adhesion, a high-quality image with a balance between density and consumption can be formed in the image area on the surface. Also, on the back surface of the sheet P, the toner amount Mr in the adhesion area can be made more than the toner amount Mgr in the image area (Mr > Mgr). Thereby, while obtaining a good adhesive force, a high-quality image with a balance between density and consumption can be formed in the image area on the back surface.

[0161] Note that FIG. 16 shows an example where the toner amount Mf in the adhesion area on the surface of one sheet P is less than the toner amount Mr in the adhesion area on the back surface. This corresponds to the case where, as in the modified example of Example 1, for all the sheets P included in the completed booklet, the toner amount Mf in the adhesion area on the surface of the sheet P is made less than the toner amount Mr in the adhesion area on the back surface. As described in Example 1, if the toner amount Mf in the adhesion area on the surface (the first surface) of the sheet P that comes into contact with the pressure plate 62 during the production of the booklet is less than the toner amount Mr on the back surface (the second surface) of the sheet P that faces the first surface, soiling of the booklet due to toner adhesion can be reduced. Note that if the toner amount Mf in the adhesion area on the first surface is less than the toner amount Mr on the second surface, the toner amount in the adhesion area on the surfaces of the sheet P other than the first surface and the second surface may be the same as the toner amounts Mgf and Mgr in the image area. Even with this configuration, soiling of the booklet due to toner adhesion can be reduced.

[0162] FIG. 13 shows the exposure light amount R (μJ / cm on the photosensitive drum Dn 2) and the amount of toner on the sheet P. The horizontal axis represents the amount of exposure light on the photosensitive drum Dn, and the vertical axis represents the amount of toner on the sheet P. From the viewpoint of adhesive strength and toner adhesion to the pressure plate 62, the amount of toner in the adhesive regions on the front and back sides of the sheet P is set to, for example, Mf=0.20 (mg / cm) for the same reason as described in the first embodiment. 2 ), Mr = 0.40 (mg / cm 2 In order to realize these toner amounts Mf and Mr, the light amount Rf when scanning the area on the photosensitive drum Dn corresponding to the adhesive area on the front side of the sheet P is set to be lower than the light amount Rr when scanning the area on the photosensitive drum Dn corresponding to the adhesive area on the back side of the sheet P (Rf <Rr)。

[0163] The toner amounts Mgf and Mgr in the image area are, for example, Mt=0.30 (mg / cm 2 ), a high-quality image with a good balance between toner density and toner consumption can be obtained. In order to realize this toner amount Mt, the light amount Rt when scanning the photosensitive drum Dn to create a normal image on the front and back sides of the sheet P is set to a value higher than the light amount Rf when scanning the photosensitive drum Dn to create an adhesive toner image on the front side. Also, the light amount Rt is set to a value lower than the light amount Rr when scanning the photosensitive drum Dn to create an adhesive toner image on the back side.

[0164] Comparative Example 1 In Comparative Example 1, in the configuration of Example 1, only the adhesive toner Tn is changed to the toner Tnbk of Example 2. Therefore, it is not possible to change the amount of exposure light depending on the position in the main scanning direction.

[0165] 7(a)-(c) in Example 1, booklets including 50 sheets P were produced multiple times, and comparisons were made for adhesive strength, toner adhesion to the pressure plate 62, toner concentration, and toner consumption. The relationship between the amount of exposure light R and the amount of toner M on the sheet P and the evaluation results for each evaluation item is shown in Table 1.

[0166] [Table 1]

[0167] The adhesive strength between the sheets P was measured in the same manner as described in Example 1 using FIG. 6(b), with 0.5 N / cm or more being rated as ◯ and less than 0.5 N / cm being rated as ×. The criteria for judging toner adhesion to the pressure plate 62 were the same as in Example 1. The concentration was measured when the toner amount M on the sheet P was equal to or greater than the reference value (0.30 mg / cm 2 The density when the toner amount M on the sheet P was the reference value (0.30 mg / cm) was indicated as ◯, the density when it was lower than the reference value was indicated as ×, and the density when it was higher than the reference value was indicated as ◎. 2 ) consumption was marked with an ◯, consumption greater than the standard value with an ×, and consumption less than the standard value with an ◎.

[0168] In Comparative Example 1, the toner amount Mf in the adhesion area on the surface was 0.2 mg / cm 2 , the toner amount in the adhesive area on the back side, Mr, is 0.4 mg / cm 2 In this case, the adhesive force and the reduction in toner adhesion to the pressure plate 62 were good results. However, in Comparative Example 1, the toner amount Mgf in the image area on the front side was 0.2 mg / cm, which was the same as the toner amount Mf in the adhesion area on the front side. 2 The appropriate toner amount for obtaining high-quality images with a good balance between density and consumption is 0.3 mg / cm. 2 Since the toner amount Mgf in the image area on the front side was small in Comparative Example 1, the toner consumption was small. Also, in Comparative Example 1, the toner amount Mgr in the image area on the back side was 0.4 mg / cm, which is the same as the toner amount Mr in the adhesive area on the back side. 2 The appropriate toner amount is 0.3 mg / cm 2 Because it is more than this amount, the concentration is sufficient but consumption is high.

[0169] In contrast, in Example 1, the amount of exposure light was changed according to the position in the main scanning direction, with Rf in the adhesive area on the front side, Rr in the adhesive area on the back side, and Rt in the image areas on the front and back sides. As a result, the toner amount Mf in the adhesive area on the front side was set to 0.2 mg / cm 2 , the toner amount in the adhesive area on the back side, Mr, is 0.4 mg / cm 2, the toner amounts Mgf and Mgr in the image areas on the front and back surfaces were set to 0.3 mg / cm 2 . As a result, while obtaining good results regarding the adhesive force and reduction of toner adhesion to the pressure plate 62, it is possible to obtain high-quality images with a better balance between density and consumption amount.

[0170] (Modification example) In this example, the exposure light amount in the adhesion area on the front surface is controlled to the light amount Rf by changing the PWM of the image signal 109, but it is not limited to this. As the correction current amount signal 113 output to the adhesion area, a voltage larger than the voltage Vc may be set, and the exposure light amount in the adhesion area may be made lower than that in the image area. Or, by combining the lighting / extinguishing of the semiconductor laser 100 for each scanning unit (for each laser spot) only in the adhesion area, the exposure light amount in the adhesion area can be similarly made artificially lower.

[0171] Also, in this example, a configuration example (FIG. 16) where Mf < Mgf and Mr > Mgr was described so as to reduce the stain of the product (booklet) in the same manner as in Example 1. However, it is not limited to this. For example, regarding the front and back surfaces of each sheet P, the toner amount in the adhesion area may be made larger than the toner amount in the image area (Mf > Mgf and Mr > Mgr) to increase the adhesive force between the sheets. Also, for example, regarding the front and back surfaces of each sheet P, the toner amount in the adhesion area may be made smaller than the toner amount in the image area (Mf < Mgf and Mr < Mgr).

[0172] 《Example 3》 In this example, an image forming apparatus capable of changing the size of the sheet P used for producing a booklet will be described. The adhesive toner image in this example is formed at the edge of the long side as shown in FIG. 5(b), and is formed in the area 2 mm to 5 mm from the end of the sheet P in the main scanning direction (Y direction).

[0173] Hereinafter, elements assigned the same reference numerals as in Examples 1 and 2 have substantially the same configuration and function as those described in Examples 1 and 2 unless otherwise particularly described, and the parts different from Examples 1 and 2 will be mainly described.

[0174] (Overall configuration of image forming apparatus) The overall configuration of the image forming apparatus 200S according to the third embodiment is the same as that described in the second embodiment (FIG. 12). In the image forming apparatus 200S, the sheet P is transported so that the center position of the image scanned and exposed by the scanner unit 2 coincides with the center position of the sheet P. Other configurations are the same as those in the second embodiment, and therefore will not be described.

[0175] (Exposure Control) The exposure control of this embodiment will be described with reference to Figures 17(a) and (b). Figure 17(a) shows the amount of exposure light with respect to the position in the main scanning direction when forming an adhesive toner image on the back side of an A4 size sheet P. As in the second embodiment, the image signal 109 becomes High in the adhesive region to form an adhesive toner image. The image signal 109 starts to be output after a time tg4 has elapsed from the falling edge of the main scanning synchronization signal 108, and outputs data including image data for forming a normal image and additional data for forming an adhesive toner image. In addition, the correction current amount signal 113 starts to be output after a time tr4 has elapsed from the falling edge of the main scanning synchronization signal 108.

[0176] The time when the above-mentioned time tg4 has elapsed from the falling edge is the time when the position on the photosensitive drum Dn corresponding to the position 2 mm from the end of the A4 size sheet P in the Y direction is scanned with the scanning light L3. The time when the above-mentioned time tr4 has elapsed from the falling edge is the time when the position on the photosensitive drum Dn corresponding to the position 5 mm from the end of the A4 size sheet P in the Y direction is scanned with the scanning light L3. By setting the times tg4 and tr4 in this manner, it is possible to set a light amount profile according to the A4 size sheet P. That is, it is possible to expose the area on the photosensitive drum Dn corresponding to the adhesive area of ​​the A4 size sheet P with the light amount Rr, and expose the area on the photosensitive drum Dn corresponding to the image area of ​​the A4 size sheet P with the light amount Rt.

[0177] 17(b) shows the exposure light amount versus position in the main scanning direction when an adhesive toner image is formed on the back side of an A5 size sheet P. The image signal 109 starts to be outputted after a time tg5 has elapsed from the falling edge of the main scanning synchronization signal 108, and outputs data including image data for forming a normal image and additional data for forming an adhesive toner image. The correction current amount signal 113 starts to be outputted after a time tr5 has elapsed from the falling edge of the main scanning synchronization signal 108.

[0178] The control of the amount of exposure light when forming an adhesive toner image on the back side of an A4-sized sheet P is the same as that for the front side, except that PWM control is performed so that the area on the photosensitive drum Dn corresponding to the adhesive area on the sheet P has a density Dh that is lower than 100% (see Figure 15(b)).

[0179] The time when the above-mentioned time tg5 has elapsed from the falling edge is the time when the position on the photosensitive drum Dn corresponding to the position 2 mm from the end of the A5 size sheet P in the Y direction is scanned with the scanning light L3. The time when the above-mentioned time tr5 has elapsed from the falling edge is the time when the position on the photosensitive drum Dn corresponding to the position 5 mm from the end of the A5 size sheet P in the Y direction is scanned with the scanning light L3. By setting the times tg5 and tr5 in this way, it is possible to set a light amount profile according to the A5 size sheet P. That is, it is possible to expose the area on the photosensitive drum Dn corresponding to the adhesive area of ​​the A5 size sheet P with the light amount Rr, and expose the area on the photosensitive drum Dn corresponding to the image area of ​​the A5 size sheet P with the light amount Rt.

[0180] The control of the amount of exposure light when forming an adhesive toner image on the back side of an A5-sized sheet P is the same as that for the front side, except that PWM control is performed so that the area on the photosensitive drum Dn corresponding to the adhesive area on the sheet P has a density Dh that is lower than 100% (see Figure 15(b)).

[0181] In this manner, in this embodiment, the controller 107 and the correction current generating unit 105 as the light amount correcting means selectively use a plurality of light amount profiles according to the sheet size in the main scanning direction. The plurality of light amount profiles are profiles in which the range in the main scanning direction in which the scanning light L3 is irradiated with the light amount Rr or Rf differs, and are determined in advance according to the sheet size.

[0182] According to this embodiment, by changing the amount of light during exposure, it is possible to change the amount of toner (toner amount) per unit area in the adhesive region on the sheet and the amount of toner (toner amount) per unit area in the image region. In other words, according to this embodiment, the amount of toner in the adhesive portion can be changed as necessary. Also, according to this embodiment, by adjusting the timing of changing the amount of exposure light according to the size of the sheet P, it is possible to obtain the same effects as those of the first and second embodiments in the booklet producing device 50 capable of producing booklets using sheets P of various sizes.

[0183] Example 4 In this embodiment, a configuration is described in which the amount of exposure light in the adhesive area and the image area can be changed as in embodiment 2, even if the laser drive circuit configuration makes it difficult to change the laser drive current according to the position in the main scanning direction as in embodiment 1.

[0184] In the following, elements having the same reference symbols as those in Examples 1 to 3 have substantially the same configurations and functions as those described in Examples 1 to 3, unless otherwise specified, and the following mainly describes the parts that differ from Examples 1 to 3.

[0185] The overall configuration of the image forming apparatus 200S according to the fourth embodiment is the same as that described in the second embodiment (FIG. 12). The laser driving circuit mounted in the scanner unit 2 according to the fourth embodiment is the same as that in the first embodiment (FIG. 11).

[0186] (Exposure Control) The exposure control of the scanner unit 2 of this embodiment will be described with reference to Figures 18(a) and (b). As in the modified example of the first embodiment, adhesive toner images are formed on the edges of the long sides of both sides of each sheet P, except for the side that will become the front or back cover of the booklet, as shown in Figure 5(b).

[0187] FIG. 18(a) shows the exposure light amount with respect to the position in the main scanning direction when forming an adhesive toner image and a normal image on the back side of the sheet P. The image signal 109 is controlled to a PWM signal (first PWM signal value) that will give a density Dr during a period when the area on the photosensitive drum Dn corresponding to the adhesive area on the back side of the sheet P is scanned. For the sake of explanation, the density Dr is set to 100%. The image signal 109 is also controlled to a PWM signal (second PWM signal value) that will give a density Dg lower than the density Dr during a period when the area on the photosensitive drum Dn corresponding to the image area on the back side of the sheet P is scanned. For this reason, even if the user transmits image data of an all-black image (a blackened image with a density of 100%) together with a print command, the controller 107 corrects the image data of the image area in units of one dot so that the density of the normal image becomes the density Dg. Even if the user transmits image data other than an all-black image, the controller 107 corrects the image data at the same ratio as the density Dg.

[0188] The laser drive current 112 is repeatedly turned ON / OFF in response to an image signal 109 that corresponds to density Dr in the adhesive region and density Dg in the image region. As a result, the region on the photosensitive drum Dn that corresponds to the adhesive region on the back side of the sheet P is scanned with the scanning light L3 having the light amount Pr, and the region on the photosensitive drum Dn that corresponds to the image region on the back side of the sheet P is scanned with the scanning light L3 having the light amount Pg that is lower than the light amount Pr of the adhesive region.

[0189] 18(b) shows the amount of exposure light with respect to the position in the main scanning direction when an adhesive toner image and a normal image are formed on the front surface of the sheet P. The image signal 109 is controlled to a PWM signal (third PWM signal value) such that the density Dh is lower than the density Dg of the image area during a period when the area on the photosensitive drum Dn corresponding to the adhesive area on the front surface of the sheet P is scanned. Also, the image signal 109 is controlled to a PWM signal (second PWM signal value) such that the density is Dg during a period when the area on the photosensitive drum Dn corresponding to the image area on the front surface of the sheet P is scanned.

[0190] The laser drive current 112 is repeatedly turned ON / OFF in response to an image signal 109 that corresponds to density Dh in the adhesive region and density Dg in the image region. As a result, the region on the photosensitive drum Dn that corresponds to the adhesive region on the surface of the sheet P is scanned with the scanning light L3 having a light amount Ps that is lower than the light amount Pg of the image region. Also, the region on the photosensitive drum Dn that corresponds to the image region on the surface of the sheet P is scanned with the scanning light L3 having the light amount Pg.

[0191] In this manner, the controller 107 serving as the light amount correction means of this embodiment corrects the amount of scanning light L3 emitted by the scanner unit 2 by pulse width modulation of the image signal 109.

[0192] According to this embodiment, even if the laser drive current is not changed according to the position in the main scanning direction, the toner amount in the adhesion area and the toner amount in the image area on the sheet P can be independently controlled according to the position in the main scanning direction. Therefore, by making the toner amount in the adhesion area on the surface (first surface) of the sheet P that contacts the pressure plate 62 during the production of the booklet less than the toner amount on the surface (second surface) of the sheet P opposite the first surface, it is possible to obtain the same effect as in the first embodiment.

[0193] According to this embodiment, by changing the amount of light during exposure, it is possible to change the toner amount (toner amount) per unit area in the adhesive area on the sheet and the toner amount (toner amount) per unit area in the image area. In other words, according to this embodiment, the toner amount in the adhesive portion can be changed as necessary. Also, by changing the control timing of the image signal 109 and the correction current amount signal 113 according to the size of the sheet P in the same manner as in the third embodiment, it is possible to obtain the same effect as in the third embodiment.

[0194] (Other embodiments) The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a 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 implements one or more of the functions.

[0195] Summary of the Disclosure The present disclosure includes at least the following configurations or methods.

[0196] (Configuration 1) an image forming means for forming an image on a sheet and applying an adhesive toner to the sheet; an adhesive means having a pressure member, and performing an adhesive operation of applying pressure and heat to the sheet stack with the pressure member, thereby adhesively adhering the sheets to each other with the adhesive toner; An image forming apparatus comprising: the bonding means performs the next bonding operation in a state in which a subsequent sheet is stacked on the previously bonded sheet stack, thereby bonding a first surface of a top sheet of the previously bonded sheet stack to a second surface of the subsequent sheet that faces the first surface; an amount of the adhesive toner applied to the first surface by the image forming means is less than an amount of the adhesive toner applied to the second surface by the image forming means; 1. An image forming apparatus comprising:

[0197] (Configuration 2) the image forming means applies the toner for adhesion to both sides of each sheet except for a surface of the sheet that will be an outer surface of the product adhered by the adhesion means; an amount of the adhesive toner applied by the image forming means to a surface of each of the sheets facing the pressure member is less than an amount of the adhesive toner applied by the image forming means to a surface of each of the sheets opposite to the facing surface; 2. The image forming apparatus according to claim 1,

[0198] (Configuration 3) The sum of the amount of the adhesive toner applied to the first surface and the amount of the adhesive toner applied to the second surface is 0.6 mg / cm 2 That's all. The total amount of the adhesive toner applied to the opposing surfaces of two adjacent sheets in the product other than the first surface and the second surface is 0.6 mg / cm 2 That's all. 3. The image forming apparatus according to claim 2,

[0199] (Configuration 4) the image forming means applies the adhesive toner to each sheet included in the product so that an adhesive strength between the sheets whose first surface and second surface are adhered to each other is 0.5 N / cm or more, and an adhesive strength between the sheets whose opposing surfaces of two adjacent sheets in the product are adhered to each other other than the first surface and the second surface is 0.5 N / cm or more; 4. The image forming apparatus according to claim 2 or 3.

[0200] (Configuration 5) the adhesive toner is the same as the toner used to create the image, the image forming means forms an adhesive toner image in an adhesive region on the sheet using the toner, and forms an image in an image region on the sheet different from the adhesive region using the toner; 5. The image forming apparatus according to any one of configurations 1 to 4.

[0201] (Configuration 6) Let the toner amount in the adhesion area on the first surface be Mf (mg / cm 2 ), and let the toner amount in the image area on the first surface be Mgf (mg / cm 2 ). When this is the case, Mf < Mgf, The image forming apparatus according to Configuration 5.

[0202] (Configuration 7) The image forming means includes an image carrier, an exposure device that emits scanning light for scanning the image carrier in the main scanning direction, and a light amount correction means for correcting the light amount of the scanning light, When the exposure light amount when scanning the area on the image carrier corresponding to the adhesion area on the first surface with the scanning light is Rf (μJ / cm 2 ), and the exposure light amount when scanning the area on the image carrier corresponding to the image area on the first surface with the scanning light is Rgf (μJ / cm 2 ). When this is the case, The light amount correction means corrects the light amount of the scanning light according to the position in the main scanning direction so that Rf < Rgf. The image forming apparatus according to Configuration 6, characterized by this.

[0203] (Configuration 8) The light amount correction means selectively uses a plurality of light amount profiles in which the range of irradiating the scanning light with the light amount of Rf in the main scanning direction is different according to the size of the sheet in the main scanning direction. The image forming apparatus according to Configuration 7, characterized by this.

[0204] (Configuration 9) Let the toner amount in the adhesion area on the second surface be Mr (mg / cm 2 ), and let the toner amount in the image area on the second surface be Mgr (mg / cm 2 ). When this is the case, Mr > Mgr, The image forming apparatus according to any one of Configurations 5 to 8.

[0205] (Configuration 10) the image forming means includes an image carrier, an exposure device that emits scanning light that scans the image carrier in a main scanning direction, and a light amount correction means that corrects the light amount of the scanning light; The amount of exposure light when scanning the area on the image carrier corresponding to the adhesion area on the second surface with the scanning light is Rr (μJ / cm 2 ), and the amount of exposure light when scanning an area on the image carrier corresponding to the image area on the second surface with the scanning light is Rrf (μJ / cm 2 ), the light amount correction means corrects the amount of the scanning light in accordance with a position in the main scanning direction so that Rr>Rrf. 10. The image forming apparatus according to claim 9,

[0206] (Configuration 11) the light amount correction means selectively uses a plurality of light amount profiles having different ranges for irradiating the scanning light with the Rr light amount in the main scanning direction in accordance with a size of the sheet in the main scanning direction. 11. The image forming apparatus according to claim 10,

[0207] (Configuration 12) an image forming means for forming an image and an adhesive toner image on a sheet; an adhesive means for applying pressure and heat to the sheet stack to bond the sheets together with the adhesive toner image; An image forming apparatus comprising: the image forming means forms the image on an image area of ​​the sheet using a toner, and forms the adhesive toner image on an adhesive area of ​​the sheet different from the image area using the toner; the toner amount per unit area in the adhesion region is different from the toner amount per unit area in the image region; 1. An image forming apparatus comprising:

[0208] (Configuration 13) The image forming means includes an image carrier, an exposure device that emits scanning light for scanning the image carrier in the main scanning direction, and a light quantity correction means for correcting the light quantity of the scanning light. The light quantity correction means corrects the light quantity of the scanning light according to the position in the main scanning direction such that the light quantity of the scanning light is different when the area on the image carrier corresponding to the image area is scanned by the scanning light and when the area on the image carrier corresponding to the adhesion area is scanned by the scanning light. The image forming apparatus according to Configuration 12, characterized in that.

[0209] (Configuration 14) When the toner amount in the adhesion area is Mf (mg / cm 2 ) and the toner amount in the image area is Mgf (mg / cm 2 ), Mf < Mgf. The image forming apparatus according to Configuration 12, characterized in that.

[0210] (Configuration 15) The image forming means includes an image carrier, an exposure device that emits scanning light for scanning the image carrier in the main scanning direction, and a light quantity correction means for correcting the light quantity of the scanning light. When the exposure light quantity when scanning the area on the image carrier corresponding to the adhesion area with the scanning light is Rf (μJ / cm 2 ) and the exposure light quantity when scanning the area on the image carrier corresponding to the image area with the scanning light is Rgf (μJ / cm 2 ), The light quantity correction means corrects the light quantity of the scanning light according to the position in the main scanning direction such that Rf < Rgf. The image forming apparatus according to Configuration 14, characterized in that.

[0211] (Configuration 16) The light quantity correction means selectively uses a plurality of light quantity profiles in which the range of irradiating the scanning light with the light quantity of Rf in the main scanning direction is different according to the size of the sheet in the main scanning direction. The image forming apparatus according to Configuration 15, characterized in that.

[0212] (Configuration 17) The amount of toner in the adhesion area is represented by Mr(mg / cm 2 ), and the toner amount in the image area is Mgr (mg / cm 2 ), Mr>Mgr. 17. The image forming apparatus according to any one of configurations 12 to 16.

[0213] (Configuration 18) the image forming means includes an image carrier, an exposure device that emits scanning light that scans the image carrier in a main scanning direction, and a light amount correction means that corrects the light amount of the scanning light; The amount of exposure light when scanning the area on the image carrier corresponding to the adhesion area with the scanning light is Rr (μJ / cm 2 ), and the amount of exposure light when scanning an area on the image carrier corresponding to the image area with the scanning light is Rrf (μJ / cm 2 ), the light amount correction means corrects the amount of the scanning light in accordance with a position in the main scanning direction so that Rr>Rrf. 18. The image forming apparatus according to claim 17,

[0214] (Configuration 19) the light amount correction means selectively uses a plurality of light amount profiles having different ranges for irradiating the scanning light with the Rr light amount in the main scanning direction in accordance with a size of the sheet in the main scanning direction. 19. The image forming apparatus according to configuration 18,

[0215] (Configuration 20) The exposure device has a light source, the light amount correction unit corrects the amount of the scanning light by changing the amount of current supplied to the light source. 20. The image forming apparatus according to any one of configurations 7, 8, 10, 11, 13, 15, 16, 18, and 19.

[0216] (Configuration 21) The exposure device has a light source, the light amount correction means corrects the amount of the scanning light by pulse width modulating a current supplied to the light source; 20. The image forming apparatus according to any one of configurations 7, 8, 10, 11, 13, 15, 16, 18, and 19.

[0217] (Configuration 22) the bonding means performs the bonding operation once every time one subsequent sheet is placed on the bonded sheet stack; 22. The image forming apparatus according to any one of configurations 1 to 21.

[0218] (Configuration 23) the bonding means performs the bonding operation once each time a predetermined number of subsequent sheets are stacked on the bonded sheet stack; 22. The image forming apparatus according to any one of configurations 1 to 21.

[0219] (Configuration 24) a stacking section on which a sheet stack to be bonded by the bonding means is stacked; an alignment mechanism that aligns the sheet conveyed to the stacking section to a position for performing the bonding operation; a stacking section that stacks the sheets conveyed one by one from the image forming section in units of the predetermined number of sheets and conveys them toward the stacking section; Further comprising: 24. The image forming apparatus according to claim 23,

[0220] (Configuration 25) The image forming means applies the toner along any one of the sides of the sheet, the bonding means produces a product in which the sheets are bonded to each other at the sides to which the toner is applied; 25. The image forming apparatus according to any one of configurations 1 to 24.

[0221] (Configuration 26) The image forming means applies the toner to any corner of the sheet, the bonding means produces a product in which the sheets are bonded to each other at the corners where the toner is applied; 25. The image forming apparatus according to any one of configurations 1 to 24.

[0222] (Configuration 27) a coating means for coating the sheet with an adhesive toner; an adhesive means having a pressure member, and performing an adhesive operation of applying pressure and heat to the sheet stack with the pressure member, thereby adhesively adhering the sheets to each other with the adhesive toner; A sheet bonding apparatus comprising: the bonding means performs the next bonding operation in a state in which a subsequent sheet is stacked on the previously bonded sheet stack, thereby bonding a first surface of a top sheet of the previously bonded sheet stack to a second surface of the subsequent sheet that faces the first surface; an amount of the adhesive toner applied by the application means to the first surface is less than an amount of the adhesive toner applied by the application means to the second surface; A sheet bonding device characterized by: [Explanation of symbols]

[0223] 1e...image forming means, coating means (image forming unit) / 2...exposure device (scanner unit) / 60...adhesive means (thermocompression unit) / 62...pressure member (pressure plate) / 105, 107...light quantity correction means (correction current generation unit, controller) / Dn...image carrier (photosensitive drum) / Tn, Tnbk...adhesive toner (adhesive toner, toner)

Claims

1. An image forming apparatus for forming a toner image on a sheet and forming a booklet in which a plurality of sheets are bonded together, Image forming means for forming the toner image and adhesive toner pattern on a sheet, An adhesive means having a pressurizing member, which performs an adhesive operation by pressing and heating the plurality of sheets with the pressurizing member to bond the sheets together via the adhesive toner pattern, Equipped with, The bonding means performs the next bonding operation with the subsequent sheet stacked on top of the multiple sheets that were bonded in the previous bonding operation, thereby bonding the first surface of the topmost sheet of the multiple sheets that were bonded together and the second surface of the subsequent sheet that is opposite the first surface. The image forming means forms the adhesive toner pattern, which is a fill pattern, on the first surface and the second surface such that the amount of toner per unit area of ​​the adhesive toner pattern formed on the first surface is less than the amount of toner per unit area of ​​the adhesive toner pattern formed on the second surface. An image forming apparatus characterized by the following features.

2. The image forming means forms the adhesive toner pattern on both sides of each sheet included in the booklet, except for the first sheet and the last sheet of the booklet. The image forming means forms the adhesive toner pattern only on the surface of the first sheet and the last sheet that faces inward from the booklet. The image forming apparatus according to feature 1.

3. The sum of the amount of toner per unit area of ​​the adhesive toner pattern on the first surface and the amount of toner per unit area of ​​the adhesive toner pattern on the second surface is 0.6 mg / cm². ２ That's all. Apart from the first and second surfaces, the total amount of toner per unit area of ​​the adhesive toner pattern formed on the opposing surfaces of two adjacent sheets in the booklet is 0.6 mg / cm². ２ That's all. The image forming apparatus according to feature 2.

4. The image forming means forms the adhesive toner pattern on each sheet included in the booklet such that the adhesive force between the sheets with the first surface and the second surface bonded together is 0.5 N / cm or more, and the adhesive force between two adjacent sheets in the booklet with their opposing surfaces bonded together is 0.5 N / cm or more. The image forming apparatus according to feature 2.

5. The image forming means forms the adhesive toner pattern in an adhesive region on the sheet using toner, and forms the toner image in an image region on the sheet different from the adhesive region using toner. The image forming apparatus according to feature 1.

6. The amount of toner per unit area in the adhesive region on the first surface is Mf (mg / cm²). ２ ) and the amount of toner per unit area in the image region on the first surface is Mgf (mg / cm²). ２ If we assume that Mf < Mgf, The image forming apparatus according to feature 5.

7. The image forming means comprises an image carrier, an exposure device that emits scanning light to scan the image carrier in the main scanning direction, and a light intensity correction means for correcting the light intensity of the scanning light. When scanning the region on the image carrier corresponding to the adhesive region on the first surface with the scanning light, the amount of exposure light Rf (μJ / cm²) ２ ) and the amount of exposure light when scanning the region on the image carrier corresponding to the image region on the first surface with the scanning light is Rgf (μJ / cm²). ２ ) If that is the case, The light intensity correction means corrects the light intensity of the scanning light according to the position in the main scanning direction so that Rf < Rgf. The image forming apparatus according to feature 6.

8. The light intensity correction means selectively uses a plurality of light intensity profiles, each with a different range of illumination of the scanning light with the Rf light intensity in the main scanning direction, depending on the size of the sheet in the main scanning direction. The image forming apparatus according to feature 7.

9. The exposure apparatus includes a light source, The light intensity correction means corrects the light intensity of the scanning light by changing the amount of current supplied to the light source. The image forming apparatus according to feature 7.

10. The exposure apparatus includes a light source, The light intensity correction means corrects the light intensity of the scanning light by pulse width modulation of the current supplied to the light source. The image forming apparatus according to feature 7.

11. The amount of toner per unit area in the adhesive region on the second surface is Mr (mg / cm²). ２ ) and the amount of toner per unit area in the image region on the second surface is Mgr (mg / cm²). ２ If we assume that Mr > Mgr, The image forming apparatus according to feature 5.

12. The image forming means comprises an image carrier, an exposure device that emits scanning light to scan the image carrier in the main scanning direction, and a light intensity correction means for correcting the light intensity of the scanning light. When the exposure light amount when scanning the area on the image carrier corresponding to the adhesion area on the second surface with the scanning light is Rr (μJ / cm ２ ), and when the exposure light amount when scanning the area on the image carrier corresponding to the image area on the second surface with the scanning light is Rrf (μJ / cm ２ ), then The light intensity correction means corrects the light intensity of the scanning light according to the position in the main scanning direction so that Rr > Rrf. The image forming apparatus according to feature 11.

13. The light intensity correction means selectively uses a plurality of light intensity profiles, each having a different range of illumination of the scanning light with the light intensity of Rr in the main scanning direction, according to the size of the sheet in the main scanning direction. The image forming apparatus according to feature 12.

14. The bonding means performs the bonding operation once each time a subsequent sheet is placed on top of the multiple sheets that have already been bonded. The image forming apparatus according to any one of claims 1 to 13.

15. The bonding means performs the bonding operation once each time a predetermined number of subsequent sheets are stacked on top of the multiple sheets that have already been bonded. The image forming apparatus according to any one of claims 1 to 13.

16. A stacking section on which sheet bundles to be bonded by the adhesive means are stacked, A matching mechanism that aligns the sheet that has been transported to the loading section to the position for performing the bonding operation, A stacking unit that stacks the sheets that have been transported one by one from the image forming means into predetermined numbers and transports them toward the stacking unit, Furthermore, The image forming apparatus according to feature 15.

17. The image forming means forms the adhesive toner pattern along any edge of the sheet. The adhesive means produces a booklet in which sheets are bonded together along the edges where the adhesive toner pattern is formed. The image forming apparatus according to any one of claims 1 to 13.

18. The image forming means forms the adhesive toner pattern on any corner of the sheet. The adhesive means produces a booklet in which sheets are bonded together at the corners where the adhesive toner pattern is formed. The image forming apparatus according to any one of claims 1 to 13.

19. An image forming apparatus for forming a toner image on a sheet and forming a booklet in which a plurality of sheets are bonded together, Image forming means for forming the toner image and adhesive toner pattern on a sheet, An adhesive means for bonding the multiple sheets together via the adhesive toner pattern by applying pressure and heating the sheets, Equipped with, The image forming means forms the adhesive toner pattern on the first surface and the second surface opposite the first surface of each sheet included in the booklet, except for the first sheet and the last sheet of the booklet. The image forming means forms the toner image in the image area of ​​the sheet using toner, and forms the adhesive toner pattern in an adhesive area of ​​the sheet that is different from the image area. The image forming means is The amount of toner per unit area in the adhesive region of the first surface is different from the amount of toner per unit area in the image region of the first surface, and The amount of toner per unit area in the adhesive region of the second surface is different from the amount of toner per unit area in the image region of the second surface. The adhesive toner pattern, which is a fill pattern, is formed on the first and second surfaces. An image forming apparatus characterized by the following features.

20. The image forming means comprises an image carrier, an exposure device that emits scanning light to scan the image carrier in the main scanning direction, and a light intensity correction means for correcting the light intensity of the scanning light. The light intensity correction means corrects the light intensity of the scanning light according to the position in the main scanning direction such that the light intensity of the scanning light differs when the scanning light scans a region on the image carrier corresponding to the image region and when the scanning light scans a region on the image carrier corresponding to the adhesion region. The image forming apparatus according to feature 19.

21. The amount of toner in the adhesive region of the first surface is Mf (mg / cm²) ２ ) and the amount of toner in the image area of ​​the first surface is Mgf (mg / cm²). ２ ), and the amount of toner per unit area in the adhesive region of the second surface is Mr (mg / cm²), and the amount of toner per unit area in the image region of the second surface is Mgr (mg / cm²), then the image forming means forms the toner image and the adhesive toner pattern on the first surface and the second surface such that Mf < Mgf for the first surface and Mr > Mgr for the second surface. The image forming apparatus according to feature 19.

22. The image forming means comprises an image carrier, an exposure device that emits scanning light to scan the image carrier in the main scanning direction, and a light intensity correction means for correcting the light intensity of the scanning light. When scanning the region on the image carrier corresponding to the adhesive region of the first surface with the scanning light, the amount of exposure light Rf (μJ / cm²) ２ ) and the amount of exposure light when scanning the region on the image carrier corresponding to the image region of the first surface with the scanning light is Rgf(μJ / cm²). ２ ) If that is the case, The light intensity correction means corrects the light intensity of the scanning light according to the position in the main scanning direction so that Rf < Rgf. The image forming apparatus according to feature 21.

23. The light intensity correction means selectively uses a plurality of light intensity profiles, each with a different range of illumination of the scanning light with the Rf light intensity in the main scanning direction, depending on the size of the sheet in the main scanning direction. The image forming apparatus according to feature 22.

24. The image forming means comprises an image carrier, an exposure device that emits scanning light to scan the image carrier in the main scanning direction, and a light intensity correction means for correcting the light intensity of the scanning light. When scanning the region on the image carrier corresponding to the adhesive region of the second surface with the scanning light, the amount of exposure light is Rr (μJ / cm²). ２ ) and the amount of exposure light when scanning the region on the image carrier corresponding to the image region of the second surface with the scanning light is Rrf (μJ / cm²). ２ ) If that is the case, The light intensity correction means corrects the light intensity of the scanning light according to the position in the main scanning direction so that Rr > Rrf. The image forming apparatus according to feature 21.

25. The light intensity correction means selectively uses a plurality of light intensity profiles, each having a different range of illumination of the scanning light with the light intensity of Rr in the main scanning direction, according to the size of the sheet in the main scanning direction. The image forming apparatus according to feature 24.

26. A sheet bonding device for forming a booklet in which a plurality of sheets are bonded together, A coating means for forming an adhesive toner pattern on a sheet using toner, An adhesive means having a pressurizing member, which performs an adhesive operation by pressing and heating multiple sheets with the pressurizing member to bond the sheets together via the adhesive toner pattern, Equipped with, The bonding means performs the next bonding operation with the subsequent sheet stacked on top of the multiple sheets that were bonded in the previous bonding operation, thereby bonding the first surface of the topmost sheet of the multiple sheets that were bonded together and the second surface of the subsequent sheet that is opposite the first surface. The coating means forms the adhesive toner pattern, which is a fill pattern, on the first surface and the second surface such that the amount of toner per unit area of ​​the adhesive toner pattern formed on the first surface is less than the amount of toner per unit area of ​​the adhesive toner pattern formed on the second surface. A sheet bonding device characterized by the following features.

27. ​​An image forming apparatus for forming a toner image on a sheet and forming a booklet in which a plurality of sheets are bonded together, Image forming means for forming the toner image and adhesive toner pattern on a sheet, An adhesive means having a pressurizing member, which performs an adhesive operation by pressing and heating the plurality of sheets with the pressurizing member to bond the sheets together via the adhesive toner pattern, Equipped with, The bonding means performs the next bonding operation with the subsequent sheet stacked on top of the multiple sheets that were bonded in the previous bonding operation, thereby bonding the first surface of the topmost sheet of the multiple sheets that were bonded together and the second surface of the subsequent sheet that is opposite the first surface. The image forming means forms the adhesive toner pattern, which is a fill pattern, on the first surface and the second surface such that the toner density of the adhesive toner pattern formed on the first surface is lower than the toner density of the adhesive toner pattern formed on the second surface. An image forming apparatus characterized by the following features.

28. An image forming apparatus for forming a toner image on a sheet and forming a booklet in which a plurality of sheets are bonded together, Image forming means for forming the toner image and adhesive toner pattern on a sheet, An adhesive means having a pressurizing member, which performs an adhesive operation by pressing and heating the plurality of sheets with the pressurizing member to bond the sheets together via the adhesive toner pattern, Equipped with, The bonding means performs the next bonding operation with the subsequent sheet stacked on top of the multiple sheets that were bonded in the previous bonding operation, thereby bonding the first surface of the topmost sheet of the multiple sheets that were bonded together and the second surface of the subsequent sheet that is opposite the first surface. The image forming means forms the adhesive toner pattern, which is a fill pattern, on the first surface and the second surface such that the thickness of the toner layer of the adhesive toner pattern formed on the first surface is less than the thickness of the toner layer of the adhesive toner pattern formed on the second surface. An image forming apparatus characterized by the following features.

29. The image forming means forms the adhesive toner pattern on both sides of each sheet included in the booklet, except for the first sheet and the last sheet of the booklet. The image forming means forms the adhesive toner pattern only on the surface of the first sheet and the last sheet that faces inward from the booklet. The image forming apparatus according to claim 27 or 28.

Images