Image forming apparatus and booklet creating method

Abstract

To provide an image forming apparatus that can obtain good booklet bonding strength even when an image pattern for bonding is formed of a plurality of toner layers.SOLUTION: An image forming apparatus comprises at least first image forming means that forms a first bonding layer with first toner on a sheet, and second image forming means that forms a second bonding layer with second toner on the first bonding layer. The first and second bonding layers form an image pattern for bonding. The image forming apparatus has booklet bonding means that stacks the plurality of sheets to form a sheet bundle, and bonds the sheets to each other to create a booklet. In the sheet bundle, at least both the first bonding layer and the second boding layer are formed on one of a first sheet and a second sheet facing each other, and at least the first bonding layer is formed on the other. The storage elastic modulus G1 of the first toner and the storage elastic modulus G2 of the second toner satisfy G1>G2.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present disclosure relates to an image forming apparatus that utilizes an electrophotographic recording method, such as a laser printer, a copier, or a facsimile, and that is capable of producing adhesive printed matter such as a booklet, and to a booklet production method. [Background technology]

[0002] There is a known method of producing a booklet by remelting the toner in a sheet stack made of multiple sheets that have been subjected to image formation processing by an image forming device such as a printer or copier, and gluing the sheets together using a booklet production device, which is a post-processing device. When such a booklet production device is installed in an image forming device that forms a color image using multiple color toners, the toner for forming the adhesive toner layer is usually determined in advance to be one color. However, forming an adhesive toner layer using only one color of toner results in a greater consumption of the adhesive toner compared to the consumption of other colors of toner. Therefore, for example, Patent Document 1 proposes a configuration in which an adhesive toner layer is formed using multiple toners in an image forming device that forms a color image in order to avoid increasing the consumption of a specific toner. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-209858 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the authors' investigation revealed that when an adhesive toner layer is formed using a plurality of toners in the production of the above-mentioned booklet, the produced booklet may not have sufficient adhesive strength. When an adhesive toner layer is formed using a plurality of toners, sufficient adhesive strength of the booklet cannot be obtained depending on the physical properties of the toner used in the adhesive layer and the stacking order of the toner layers. In order to ensure sufficient adhesive strength of the booklet, it is considered necessary to ensure that the adhesive toner layer is thicker than a certain thickness and that there are few gaps between the toner layers. If the adhesive toner layer is thin, there are likely to be areas where the toner layer is not present locally. As a result, the adhesive area is reduced, and peeling is likely to occur at the interface between the sheet and the toner layer, resulting in a decrease in adhesive strength. Furthermore, the gaps between the toner layers become the starting point for adhesive failure. As a result, the adhesive toner layer is prone to cohesive failure, resulting in a decrease in adhesive strength.

[0005] The present disclosure is directed to an image forming apparatus and a booklet producing method that can obtain favorable booklet adhesive strength even when an adhesive image pattern is formed using a plurality of toner layers. [Means for solving the problem]

[0006] At least one aspect of the present disclosure is an image forming apparatus, The image forming apparatus includes at least a first image forming means for forming a first adhesive layer on a sheet by a first toner; a second image forming means for forming a second adhesive layer on the first adhesive layer by a second toner; an adhesive image pattern is formed by the first adhesive layer and the second adhesive layer; The image forming apparatus stacks a plurality of the sheets to form a sheet bundle, and heats and presses the sheet bundle to bond the sheets together via the adhesive image pattern to form a booklet. A fastening means is provided. In the sheet bundle, at least both the first adhesive layer and the second adhesive layer are formed on one of the opposing first sheet and second sheet, At least the first adhesive layer is formed on the other side, When the storage modulus of the first toner forming the first adhesive layer is G1 and the storage modulus of the second toner forming the second adhesive layer is G2, The image forming apparatus relates to a device in which G1 and G2 satisfy G1>G2.

[0007] Another aspect of the present disclosure is an image forming apparatus, The image forming apparatus includes at least a first image forming means for forming a first adhesive layer on a sheet by a first toner; a second image forming means for forming a second adhesive layer on the first adhesive layer using a second toner, and a third image forming means for forming a third adhesive layer using a third toner; an adhesive image pattern is formed by the first adhesive layer, the second adhesive layer and the third adhesive layer; the image forming apparatus has a booklet bonding means for stacking a plurality of the sheets to form a sheet bundle, and bonding the sheets together via the bonding image pattern by applying heat and pressure to the sheet bundle to form a booklet; In the sheet bundle, one of the opposing first sheet and second sheet has both the first adhesive layer and the second adhesive layer formed thereon; At least the third adhesive layer is formed on the other side, When the storage elastic modulus of the first toner forming the first adhesive layer is G1, the storage elastic modulus of the second toner forming the second adhesive layer is G2, and the storage elastic modulus of the third toner forming the third adhesive layer is G3, The image forming apparatus relates to a device in which G1, G2 and G3 satisfy G1>G2 and G3>G2.

[0008] Yet another aspect of the present disclosure is an image forming apparatus, The image forming apparatus includes: a first image forming means for forming a first adhesive layer on a sheet by a first toner; a second image forming means for forming a second adhesive layer by a second toner on the first adhesive layer, a third image forming means for forming a third adhesive layer by a third toner on the second adhesive layer, and a fourth image forming means for forming a fourth adhesive layer by a fourth toner on the third adhesive layer, an adhesive image pattern is formed by at least three adhesive layers among the first adhesive layer, the second adhesive layer, the third adhesive layer, and the fourth adhesive layer; the image forming apparatus has a booklet bonding means for stacking a plurality of the sheets to form a sheet bundle, and bonding the sheets together via the bonding image pattern by applying heat and pressure to the sheet bundle to form a booklet; In the sheet bundle, all of the adhesive image patterns are formed on one of the opposing first sheet and second sheet, In the sheet bundle, among the at least three adhesive layers forming the adhesive image pattern, the storage elastic modulus of the toner forming the adhesive layer A adjacent to the sheet is defined as GA, and the storage elastic modulus of the toner forming the adhesive layer B other than the adhesive layer A is defined as GB. The present invention relates to an image forming apparatus, in which GA and GB satisfy GA>GB. Effect of the Invention

[0009] According to the present disclosure, even when an image pattern for adhesion is formed using a plurality of toner layers, it is possible to obtain a good booklet adhesive strength. [Brief description of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view of an image forming apparatus and a post-processing apparatus according to a first embodiment of the present invention; [Diagram 2] FIG. 1 is a schematic diagram showing a sheet alignment method of a post-processing device; [Diagram 3] Cross-sectional view showing the configuration of a thermocompression bonding unit [Figure 4] Schematic diagram showing the printing area of ​​the adhesive portion [Diagram 5]Measurement results of toner storage modulus [Figure 6] Schematic diagram showing the booklet adhesive strength test method [Figure 7] FIG. 1 shows the layering order of toner in the adhesive layer of Example 1. [Figure 8] Schematic diagram showing the molten state of the toner in the adhesive layer after the adhesion treatment. [Figure 9] FIG. 13 is a cross-sectional view showing a configuration of a modified example of an image forming apparatus. [Figure 10] FIG. 13 is a diagram showing the layering order of toner in the adhesive layer of Example 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The present disclosure will be described in detail below, but the present disclosure is not limited to these descriptions. In the present disclosure, the description of "XX or more and YY or less" or "XX to YY" representing a numerical range means a numerical range including a lower limit and an upper limit as endpoints, unless otherwise specified. When a numerical range is described in stages, the upper limit and the lower limit of each numerical range can be arbitrarily combined. EXAMPLES

[0012] <Image forming apparatus and operation> 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 1 according to a first embodiment, which will be described later. 1, the image forming apparatus 1 includes a sheet cassette 8 as a sheet storage unit that stores sheets P as recording materials, an image forming unit 1e as an image forming means, a fixing device 6 as a fixing means, and a housing 19 that houses these. The image forming apparatus 1 has a printing function of forming a toner image on a sheet P fed from the sheet cassette 8 by the image forming unit 1e, and producing a printed matter that has been subjected to a fixing process by the fixing device 6.

[0013] The size of the sheet is not particularly limited and may be changed as appropriate according to the size of the image forming device to be used. In the embodiment described later, the maximum size of the sheet P in the conveying direction on which an image can be formed is A4 size (297 mm length x 210 mm width), and the image is formed by conveying the A4 size in the vertical direction. The sheet conveying speed is also not particularly limited, and is 300 mm / sec in the embodiment described later.

[0014] The sheet cassette 8 is inserted into the housing 19 at the bottom of the image forming apparatus 1 so as to be removable, and stores a large number of sheets P. The sheets P stored in the sheet cassette 8 are fed from the sheet cassette 8 by a sheet feed roller 8a serving as a paper feed section, and are transported by a transport roller pair 8b. It is also possible to feed sheets set in the multi-tray 20 one by one.

[0015] The image forming unit 1e is a tandem-type electrophotographic unit equipped with four process cartridges 7y, 7m, 7c, and 7k, a scanner unit 2, and a transfer unit 3. A process cartridge is a unit in which multiple parts responsible for an image forming process are integrated into one unit that can be replaced.

[0016] Each of the process cartridges 7y, 7m, 7c, and 7k has a substantially common configuration except for the type of toner contained in the four toner containers Ky, Km, Kc, and Kk. That is, each of the process cartridges 7y, 7m, 7c, and 7k has a photosensitive drum Dy, which is an image carrier. , Dm, Dc, Dk, charging rollers Cy, Cm, Cc, Ck which are chargers, and toner containers Ky, Km, Kc, Kk which store toner and supply it to the photosensitive drum.

[0017] The four toner storage sections Ky, Km, Kc, and Kk store printing toners of yellow (Ty), magenta (Tm), cyan (Tc), and black (Tk), respectively, as toners for forming visible images on the sheet P. These toners for forming visible images can also be used as adhesive toners as powder adhesives (hereinafter simply referred to as "toner") for performing an adhesive process after printing.

[0018] The scanner unit 2 is disposed below the process cartridges 7y, 7m, 7c, and 7k and above the sheet cassette 8. The scanner unit 2 is an exposure unit that writes an electrostatic latent image by irradiating the photosensitive drums Dy, Dm, Dc, and Dk of the process cartridges 7y, 7m, 7c, and 7k with laser beams Jy, Jm, Jc, and Jk.

[0019] The transfer unit 3 includes a transfer belt 3a as an intermediate transfer body (secondary image carrier). The transfer belt 3a is a belt member wound around a secondary transfer inner roller 3b and a tension roller 3c, and its outer circumferential surface faces the photosensitive drums Dy, Dm, Dc, and Dk of each process cartridge 7y, 7m, 7c, and 7k. Primary transfer rollers Fy, Fm, Fc, and Fk are disposed on the inner circumferential side of the transfer belt 3a at positions corresponding to the photosensitive drums Dy, Dm, Dc, and Dk. In addition, a secondary transfer roller 5 as a transfer means is disposed at a position facing the secondary transfer inner roller 3b. A transfer nip 5n between the secondary transfer roller 5 and the transfer belt 3a is a transfer portion (secondary transfer portion) where a toner image is transferred from the transfer belt 3a to a sheet P. A fixing device 6 is disposed above the secondary transfer roller 5.

[0020] The fixing device 6 has a cylindrical fixing film (endless belt) 6a as a heating rotator, a pressure roller 6c as a pressure member, a heater 6b as a heating means that contacts the inner surface of the fixing film 6a, and the pressure roller 6c as a pressure rotator that forms a fixing nip portion 6n with the heater 6b via the fixing film 6a.

[0021] Next, the operation of the image forming apparatus 1 will be described again with reference to Fig. 1. When data of an image such as an adhesive image pattern to be printed and a command to execute printing are input to the image forming apparatus 1, a control unit (not shown) of the image forming apparatus 1 starts a series of operations (image forming operations) for conveying a sheet P and forming an image on the sheet P. In the image forming operation, first, the sheets P are fed one by one from the sheet cassette 8 and conveyed toward the transfer nip 5n via a conveying roller 8b.

[0022] In parallel with the feeding of the sheet P, the process cartridges 7y, 7m, 7c, and 7k are driven in sequence, and the photosensitive drums Dy, Dm, Dc, and Dk are rotated. At this time, the photosensitive drums Dy, Dm, Dc, and Dk are uniformly charged on their surfaces by the charging rollers Cy, Cm, Cc, and Ck. The scanner unit 2 also irradiates the photosensitive drums Dy, Dm, Dc, and Dk of the process cartridges 7y, 7m, 7c, and 7k with laser light modulated based on image data, forming electrostatic latent images on the surfaces of the photosensitive drums Dy, Dm, Dc, and Dk. Next, the electrostatic latent images on the photosensitive drums Dy, Dm, Dc, and Dk are developed into toner images by the toner carried by the developing rollers Hy, Hm, Hc, and Hk in the toner storage units Ky, Km, Kc, and Kk of the process cartridges 7y, 7m, 7c, and 7k.

[0023] The transfer belt 3a rotates in a counterclockwise direction (arrow V) in the figure. The toner images formed in the process cartridges 7y, 7m, 7c, and 7k are primarily transferred from the photosensitive drums Dy, Dm, Dc, and Dk to the transfer belt 3a by an electric field formed between the photosensitive drums Dy, Dm, Dc, and Dk and the primary transfer rollers Fy, Fm, Fc, and Fk.

[0024] The toner image carried by the transfer belt 3a and reaching the transfer nip 5n is secondarily transferred onto the conveyed sheet P by an electric field formed between the secondary transfer roller 5 and the inner secondary transfer roller 3b.

[0025] In the toner image formed on the sheet P after the secondary transfer, when the toner image contains all four color toners, black toner Tk is disposed at the position closest to the sheet P. Cyan toner Tc is disposed on the black toner Tk, magenta toner Tm is disposed on the cyan toner Tc, and yellow toner Ty is disposed at the position furthest from the sheet P.

[0026] 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 toners Ty, Tm, Tc, and Tk melt and then adhere to each other to form an adhesive layer, thereby obtaining an image such as an adhesive image pattern fixed to the sheet P.

[0027] The switching guide 33 is a flap-shaped guide member for switching the conveying direction when a single-sided printing mode is selected in which an image is formed on one side of the sheet P, or a double-sided printing mode is selected in which images are formed on both sides of the sheet P. In the single-sided printing mode, the switching guide 33 conveys the sheet P to the pair of paper discharge rollers 34.

[0028] On the other hand, in the double-sided printing mode, the switching guide 33 conveys the sheet P to the switchback roller pair 35, which reverses its rotational direction after discharging the sheet P to the rear end, thereby conveying the sheet P to the double-sided conveying path 36 for double-sided printing. The sheet P conveyed to the double-sided conveying path 36 passes through the secondary transfer section and the fixing section again, whereby an image such as an adhesive layer is formed on a second surface (unprinted sheet surface) opposite to the first surface of the sheet. Thereafter, the sheet P on which the image has been formed is conveyed by the switching guide 33 to the discharge roller pair 34, which conveys the sheet P to the post-processing device 300 via an intermediate conveying unit 200 having conveying roller pairs 201 and 202.

[0029] The post-processing device 300 is of a floor-standing type, and is equipped with a sheet alignment means at the bottom and a thermocompression bonding unit 51 as a booklet bonding device that heats and presses the aligned sheet stack for a predetermined period of time. In the embodiment described later, the sheet conveying speed of the intermediate conveying unit 200 and the post-processing device 300 is 600 mm / sec.

[0030] The image forming apparatus has a booklet bonding means for stacking a plurality of sheets on which an adhesive image pattern is formed by an adhesive layer to form a sheet bundle, and bonding the sheets together via the adhesive image pattern by heating and pressurizing the sheet bundle to form a booklet. The thermocompression bonding unit 51 is such a booklet bonding means.

[0031] The sheet P conveyed from the intermediate conveying unit 200 is delivered to a pair of conveying rollers 21 of the post-processing device 300. The conveying rollers 22 accelerate the sheet at a predetermined timing based on the time when the rear end passes through the entrance sensor 27. In image formation in which the sheets are not bonded to each other, if the sheet is to be discharged to the upper discharge tray 25, the sheet is decelerated to a predetermined discharge speed when the rear end of the sheet reaches between the conveying rollers 22 and the reversing rollers 24 and is discharged to the upper discharge tray 25.

[0032] When sheets are bonded together to obtain a booklet, the bonded booklet is discharged from the lower discharge tray 37 via the thermocompression bonding unit 51. In this case, the sheet transport is temporarily stopped when the rear end of the sheet passes through the check valve 23, which is biased clockwise in the figure by a spring (not shown), and then the sheet is switched back and transported to the inner discharge rollers 26.

[0033] The sheet P conveyed from the internal discharge roller 26 is sent to the kick-out roller 29 via the intermediate conveying roller 28, and is conveyed to the intermediate stacking section 42. A vertical alignment reference plate 39 is disposed at the most downstream portion of the intermediate stacking section 42, and the sheet stack is aligned by abutting the end of the sheet in the conveying direction against this plate.

[0034] The sheet alignment method will be described with reference to Fig. 1 and Figs. 2A to 2D. Here, the longitudinal direction of the sheet P is defined as the Y direction, the lateral direction as the X direction, and the height direction as the Z direction. As shown in Fig. 2A, a half-moon roller 40 for pushing the sheet P that has passed through the kick-out rollers 29 onto the longitudinal alignment reference plate 39 is rotatably supported in the intermediate stacking section 42. The half-moon roller 40 transports the sheet towards the longitudinal alignment reference plate 39 at a predetermined timing. As shown in Fig. 2B, the transport pressure of the half-moon roller 40 is adjusted so that the roller slips on the sheet after the sheet comes into contact with the longitudinal alignment reference plate 39.

[0035] After the sheets reach the vertical alignment reference plate, an alignment operation is performed until the horizontal alignment jogger 41a hits the horizontal alignment reference plate 500 (dotted line) as shown in Fig. 2C, and the sheet stack is aligned in a predetermined position as shown in Fig. 2D. The operations in Fig. 2C and 2D are performed in a batch for each predetermined number of sheets in conjunction with the binding operation by the thermocompression bonding unit 51 as a sheet bonding means. The thermocompression bonding unit 51 creates a booklet with the left end bound or the right end bound by subjecting a sheet bundle made up of a plurality of sheets P to a thermocompression process. The sheet bundle that is aligned vertically and horizontally is subjected to a heating and pressurizing process by the thermocompression bonding unit 51, making it possible to create a booklet that is aligned with high precision.

[0036] The structure of the thermocompression bonding unit 51 will be further described. Fig. 3A is a cross-sectional view of the thermocompression bonding unit 51, in which an aluminum heating plate 502 is placed on a ceramic heater 501 incorporating a heating element as a heat source. In the examples described below, the dimensions of the ceramic heater are a thickness of 1.0 mm, a width of 8.0 mm, and a length of 350 mm. The ceramic heater 501 can be controlled to an arbitrary set temperature by a temperature detection means and a power application means supported by a heater support 503 (not shown).

[0037] In the examples described later, the set temperature was adjusted so that the surface temperature of the pressure applying part A of the heating plate 502 was 200°C. By providing the pressure applying part A on the heating plate 502, the heat and pressure of the thermocompression bonding unit 51 can be concentrated only on the portion where the image pattern for adhesion is present, which is the binding position of the sheet stack, and heating and pressure processing can be performed efficiently. The ceramic heater is supported by a heater support 503 made of resin. The degree of heating and pressing can be set according to the melting characteristics of the toner. For example, the peak temperature of the adhesive image pattern is preferably set to 90 to 140° C., more preferably 110 to 130° C. The surface temperature of the pressing unit A is, for example, 180 to 240° C.

[0038] The pressure lever 504 obtains power from a drive source (not shown) to press down the thermocompression bonding unit 51 in the -Z direction (downward) and apply pressure to the sheet stack. The pressure of the pressure lever 504 is transmitted via a metal stay 505 as a rigid body. In an embodiment described later, the pressure lever 504 applies a total pressure of 30 kgf to the sheet stack P. Here, 506 is a pressure plate made of silicone rubber with a thickness of 2.0 mm, which is a member for stably receiving the pressure. The pressure during pressure application may be sufficient to form a sheet stack, and the total pressure on the sheet stack P is preferably 25 to 50 kgf, and more preferably 28 to 40 kgf.

[0039] In the embodiment described later, the thermocompression bonding unit 51 presses the sheet stack for 2 seconds and then separates. 2 Up to five sheets P can be bonded at once. FIG. 3B shows the cross-sectional shape of the heating plate 502. The pressing portion A has a flat portion of 1.0 mm and curved portions of R1.5 on both sides of the flat portion. The length of the heating plate 502 in the Y direction is 300 mm.

[0040] Also, as shown in FIG. 3A, after the adhesive process is performed once by the thermocompression bonding unit 51 (P1-1 to P1-5), as shown in FIG. 3C, the sheets P may be stacked in order on top of the sheets (P2-1 to P2-4), and P1-1 to 5 and P2-1 to 4 may be bonded together. This makes it possible to produce a product with a large number of booklets. In the embodiment described later, five sheets P are supplied the first time, and then a maximum of four sheets are supplied at a time, making it possible to produce a booklet of up to 50 sheets. During continuous operation, the sheets P are supplied to the thermocompression bonding unit 51, and the thermocompression bonding unit 51 repeats a lowering operation, a pressurizing operation (for two seconds), and an ascending operation, thereby enabling efficient booklet production.

[0041] After the bonding process by the thermocompression bonding unit 51 is completed, a bundle discharge guide (not shown) moves parallel from the standby position toward the sheet discharge port 45 to push out the booklet. A bundle discharge roller 38 is provided at the sheet discharge port 45. The bundle discharge guide stops at a position where the leading edge of the booklet slightly passes the bundle discharge roller 38 and returns to the standby position again. The bundle discharge roller 38 discharges the booklet received from the bundle discharge guide onto the lower discharge tray 37.

[0042] In the present disclosure, the image forming apparatus includes an image forming means for forming an adhesive image pattern including an adhesive layer made of a toner on a sheet; and a booklet bonding means for stacking a plurality of the sheets on which the adhesive image pattern is formed to form a sheet bundle, and bonding the sheets together via the adhesive image pattern to form a booklet by heating and pressurizing the sheet bundle. The adhesive image pattern has at least three adhesive layers made of toner, and each of the at least three adhesive layers is formed of a different toner. In addition, in the sheet bundle, of at least three adhesive layers forming an adhesive image pattern, the storage modulus of the toner forming adhesive layer A, which is the adhesive layer adjacent to the sheet, is defined as GA. In addition, of at least three adhesive layers, the storage modulus of the toner forming adhesive layer B, which is the adhesive layer other than adhesive layer A, is defined as GB. In this case, GA and GB satisfy GA>GB. That is, this means that in the adhesive image pattern, the storage modulus of the toner in the adhesive layer in contact with the sheet is higher than the storage modulus of the toner in the other adhesive layers (adhesive layers not in contact with the sheet).

[0043] Since there are at least three adhesive layers in the adhesive image pattern between the first sheet and the second sheet, which are two opposing sheets in a sheet stack, there can be two types of toners forming the adhesive layer A, for which GA is measured. The storage modulus GA of both of these two types of toners is greater than GB. When the adhesive layer has four layers instead of at least three layers, or when there are more than two layers, there will be multiple types of toners forming the adhesive layer B, for which GB is measured, and in that case, whichever GA and GB are selected, GA>GB will be satisfied. By setting the storage modulus in this relationship, good booklet adhesive strength can be obtained even when the adhesive image pattern is formed with multiple toner layers. The reason for this will be explained in the later section <Mechanism of booklet adhesive strength expression>.

[0044] The present disclosure may also provide a method for producing a booklet. The booklet production method includes: forming an adhesive image pattern including an adhesive layer made of toner on a sheet by an image forming means; A plurality of the sheets on which the adhesive image pattern is formed are stacked to form a sheet bundle, and the sheets are bonded together via the adhesive image pattern by heating and pressurizing the sheet bundle to form a booklet. and a booklet adhesive means. In the adhesive image pattern, at least three adhesive layers are formed by toner, and the at least three adhesive layers are formed by different toners, and the toners used in the three adhesive layers satisfy the relationship GA>GB as described in the image forming apparatus. The formation of the adhesive image pattern having at least three adhesive layers and the production of the booklet can be performed by the above-mentioned image forming apparatus. The formation of each adhesive layer will be described below in more specific embodiments.

[0045] (At least one aspect of the present disclosure) Each aspect will be described below. In each of the following aspects, the image forming apparatus described above can be adopted. In at least one embodiment of the present disclosure, the image forming apparatus can include a first image forming means for forming a first adhesive layer on a sheet using a first toner, and a second image forming means for forming a second adhesive layer on the first adhesive layer using a second toner. That is, the image forming means includes at least a first image forming means and a second image forming means. The image forming means may include a third image forming means for forming a third adhesive layer on the second adhesive layer using a third toner. These image forming means may correspond to the above-mentioned process cartridges 7y, 7m, 7c, and 7k.

[0046] For example, a first adhesive layer formed by a first toner and a second adhesive layer formed by a second toner can be superimposed in this order on the first surface of the sheet, so that the second adhesive layer is the surface. That is, at least the sheet, the first adhesive layer, and the second adhesive layer are formed in this order. For example, an additional adhesive layer may be provided on the second adhesive layer within a range that does not impair the effects of the present disclosure. An adhesive image pattern is formed by these first adhesive layer and second adhesive layer.

[0047] In addition, the first toner may contain toners of multiple colors, and the second toner may contain toners of multiple colors, as long as the effects of the present disclosure are not impaired. In addition, the first toner and the second toner may be toners of the same color, as long as the effects of the present disclosure are not impaired.

[0048] The first toner is preferably a black toner Tk, and the second toner is preferably at least one selected from the group consisting of a cyan toner Tc, a magenta toner Tm, and a yellow toner Ty. The first image forming means is preferably a process cartridge having black toner Tk, and the second image forming means is preferably a process cartridge having cyan toner Tc, a process cartridge having magenta toner Tm, or a process cartridge having yellow toner Ty.

[0049] Then, a plurality of sheets on which an adhesive image pattern is formed by an adhesive layer are stacked to form a sheet bundle, and the sheet bundle is heated and pressurized to bond the sheets together via the adhesive image pattern to form a booklet. For example, a plurality of sheets on which an adhesive layer is formed are stacked to obtain a sheet bundle, and the sheets are heated at the adhesive image pattern formed by the adhesive layer in the sheet bundle to bond the sheets together, thereby obtaining a booklet.

[0050] In at least one embodiment of the present disclosure, at least a first adhesive layer and a second adhesive layer are formed on one of two opposing sheets, a first sheet and a second sheet, in a sheet bundle. At least a first adhesive layer is formed on the other sheet (FIGS. 7A to 7C). In this manner, an adhesive image pattern is formed by at least three adhesive layers. For example, a first adhesive layer, a second adhesive layer, and a first adhesive layer are formed in this order between the sheets. This will be the case.

[0051] Moreover, a third adhesive layer may be further formed on the first adhesive layer and the second adhesive layer. Fig. 7C shows an example in which an adhesive layer made of Tm is further formed. A second adhesive layer may be further provided on the other first adhesive layer. For example, both the first adhesive layer and the second adhesive layer may be formed on the other. Figure 7B shows an example in which the first adhesive layer and the second adhesive layer are formed on both the first sheet and the second sheet, which are two opposing sheets.

[0052] By adopting the above-mentioned double-sided printing mode, such a sheet bundle can be produced. For example, both the first adhesive layer and the second adhesive layer are formed on one side of a sheet, and at least the first adhesive layer is formed on the other side. A sheet bundle can be produced by stacking a plurality of sheets on which adhesive layers are formed in this way. As a result, an adhesive image pattern having at least three adhesive layers is formed between the sheets. It is preferable that no adhesive layer is formed on the front side of the sheet bundle that can become the cover of the booklet. The number of sheets included in the sheet bundle can be set arbitrarily. The plurality of sheets may be two sheets or more.

[0053] In at least one embodiment of the present disclosure, the storage modulus of the first toner forming the first adhesive layer is G1, and the storage modulus of the second toner forming the second adhesive layer is G2. In this case, G1 and G2 satisfy G1>G2. For example, in Figures 7A and 7B, the storage modulus of the black toner Tk adjacent to the sheet corresponds to G1. By setting the storage modulus in this relationship, good booklet adhesive strength can be obtained even when the adhesive image pattern is formed with multiple toner layers. The reason for this will be explained in the later section <Mechanism of booklet adhesive strength expression>. In at least one embodiment of the present disclosure, G1 corresponds to the above-mentioned GA, and G2 corresponds to the above-mentioned GB.

[0054] (Another aspect of the present disclosure) In another aspect of the present disclosure, the image forming apparatus can include a first image forming means for forming a first adhesive layer on a sheet using a first toner, a second image forming means for forming a second adhesive layer on the first adhesive layer using a second toner, and a third image forming means for forming a third adhesive layer using a third toner. That is, the image forming means includes at least a first image forming means, a second image forming means, and a third image forming means. The image forming means are the same as those described above. An adhesive image pattern is formed by the first adhesive layer, the second adhesive layer, and the third adhesive layer.

[0055] The image forming apparatus has a booklet bonding means for stacking a plurality of sheets on which adhesive layers have been formed to form a sheet bundle, and bonding the sheets together via the image pattern for bonding by the adhesive layers by heating and pressurizing the sheet bundle to form a booklet. In the sheet bundle, both the first adhesive layer and the second adhesive layer are formed on one of two opposing sheets, a first sheet and a second sheet, and at least the third adhesive layer is formed on the other (FIG. 10A). In this way, an image pattern for bonding by at least three adhesive layers is formed, and for example, the first adhesive layer, the second adhesive layer, and the third adhesive layer are formed between the sheets in this order. As long as the effects of the present disclosure are not impaired, a fourth adhesive layer may be further provided on the other third adhesive layer, i.e., between the second adhesive layer and the third adhesive layer.

[0056] By adopting the above-mentioned double-sided printing mode, such a sheet bundle can be produced. For example, a first adhesive layer formed by a first toner and a second adhesive layer formed by a second toner are superimposed in this order on a first surface of a sheet, and the second adhesive layer is Then, a third adhesive layer can be formed on another sheet using a third toner.

[0057] Alternatively, a first adhesive layer formed by a first toner and a second adhesive layer formed by a second toner are superimposed in this order on a first surface of the sheet. Then, a third adhesive layer formed by a third toner may be formed on a second surface opposite to the first surface of the sheet. A sheet bundle may be produced by stacking a plurality of sheets on which adhesive layers have been formed in this manner. It is preferable not to form an adhesive layer on the front surface side of the sheet bundle that may become the cover of the booklet. The number of sheets may be set as desired.

[0058] In addition, within the scope of the present disclosure, the first toner may contain toners of multiple colors, and the second toner may contain toners of multiple colors. In addition, the third toner may contain toners of multiple colors. In addition, within the scope of the present disclosure, two or more toners selected from the group consisting of the first toner, the second toner, and the third toner may be toners of the same color.

[0059] The first toner is preferably a black toner Tk, the second toner is preferably at least one selected from the group consisting of a cyan toner Tc and a magenta toner Tm, and the third toner is preferably a yellow toner Ty.

[0060] Then, the sheets on which the adhesive layer is formed are stacked to form a sheet bundle, and the sheet bundle is heated and pressurized to bond the sheets together via the image pattern for adhesion by the adhesive layer, thereby obtaining a booklet. For example, the adhesive layer in the sheet bundle is heated.

[0061] In another embodiment of the present disclosure, the storage modulus of the first toner forming the first adhesive layer is G1, the storage modulus of the second toner forming the second adhesive layer is G2, and the storage modulus of the third toner forming the third adhesive layer is G3. In this case, G1, G2, and G3 satisfy G1>G2 and G3>G2. For example, in FIG. 10A, the storage modulus of the black toner Tk adjacent to the sheet corresponds to G1, and the storage modulus of the yellow toner Ty corresponds to G3. By setting the storage modulus in this relationship, good booklet adhesive strength can be obtained even when the adhesive image pattern is formed with multiple toner layers. The reason for this will be explained in the later section <Mechanism of booklet adhesive strength expression>. In another embodiment of the present disclosure, G1 and G3 correspond to the above-mentioned GA, and G2 corresponds to the above-mentioned GB.

[0062] (Still another aspect of the present disclosure) In yet another aspect of the present disclosure, the image forming apparatus may include a first image forming means for forming a first adhesive layer on a sheet using a first toner, a second image forming means for forming a second adhesive layer on the first adhesive layer using a second toner, a third image forming means for forming a third adhesive layer on the second adhesive layer using a third toner, and a fourth image forming means for forming a fourth adhesive layer on the third adhesive layer using a fourth toner. That is, the image forming means includes at least a first image forming means, a second image forming means, a third image forming means, and a fourth image forming means. The image forming means are the same as those described above. An adhesive image pattern is formed by at least three adhesive layers of the first adhesive layer, the second adhesive layer, the third adhesive layer, and the fourth adhesive layer.

[0063] The image forming apparatus has a booklet bonding means for stacking a plurality of sheets on which an adhesive image pattern is formed by an adhesive layer to form a sheet bundle, and bonding the sheets together via the adhesive image pattern by heating and pressurizing the sheet bundle to form a booklet. In the sheet bundle, at least three bonding patterns are formed on one of the first sheet and the second sheet, which are two opposing sheets. All of the adhesive image patterns are formed by the adhesive layers (FIG. 10B). The adhesive layers may be at least three layers, and may be four layers. For example, an adhesive image pattern may be formed by a first adhesive layer, a second adhesive layer, a third adhesive layer, and a fourth adhesive layer (FIG. 10C).

[0064] By adopting the above-mentioned single-sided printing mode, such a sheet bundle can be produced. For example, an adhesive image pattern can be formed on the first surface of a sheet by superposing a first adhesive layer, a second adhesive layer, a third adhesive layer, and a fourth adhesive layer in this order. A sheet bundle may be produced by stacking a plurality of sheets on which an adhesive layer is formed in this manner. It is preferable that no adhesive layer is formed on the front surface side of the sheet bundle that will become the cover of the booklet. The number of sheets may be set as desired.

[0065] In addition, within the scope of the present disclosure, the first toner may contain toners of multiple colors, and the second toner may contain toners of multiple colors. In addition, the third toner may contain toners of multiple colors. In addition, within the scope of the present disclosure, two or more toners selected from the group consisting of the first toner, the second toner, the third toner, and the fourth toner may be toners of the same color.

[0066] The first toner is preferably a black toner Tk, the second toner is preferably one of a cyan toner Tc and a magenta toner Tm, the third toner is preferably the other of a cyan toner Tc and a magenta toner Tm, and the fourth toner is preferably a yellow toner.

[0067] Then, the sheets on which the adhesive image pattern is formed by the adhesive layer are stacked to form a sheet bundle, and the sheet bundle is heated and pressurized to bond the sheets together via the adhesive image pattern. For example, the adhesive image pattern in the sheet bundle may be heated.

[0068] In yet another embodiment of the present disclosure, in a sheet bundle, among at least three adhesive layers forming an adhesive image pattern, the storage modulus of the toner forming adhesive layer A, which is the adhesive layer adjacent to the sheet, is defined as GA. In addition, among at least three adhesive layers, the storage modulus of the toner forming adhesive layer B, which is the adhesive layer other than adhesive layer A, is defined as GB. In this case, GA and GB satisfy GA>GB. That is, as in the above, this means that in the adhesive image pattern, the storage modulus of the toner in the adhesive layer in contact with the sheet is higher than the storage modulus of the toner in the other adhesive layers.

[0069] For example, in the case of FIG. 10B, the storage modulus of Ty and Tk corresponds to GA, and the storage modulus of Tc corresponds to GB. Also, in the case of FIG. 10C, the storage modulus of Ty and Tk corresponds to GA, and the storage modulus of Tm and Tc corresponds to GB. Regardless of which toner is selected that corresponds to GA or GB, GA>GB is satisfied. For example, the storage modulus of the first toner is higher than that of the second toner, and the storage modulus of the fourth toner is higher than that of the third toner. By setting the storage modulus in this relationship, good booklet adhesive strength can be obtained even when the adhesive image pattern is formed with multiple toner layers. The reason for this will be explained in the later section <Mechanism of booklet adhesive strength expression>.

[0070] (Storage modulus) As described above, in the present disclosure, the storage modulus of the toner in the adhesive layer in contact with the sheet is higher than the storage modulus of the toner in the other adhesive layers. The temperature at which the storage modulus is measured is preferably the peak value of the temperature of the adhesive layer (adhesive image pattern) during operation of the booklet bonding means, and more preferably 120° C. In other words, the storage modulus is more preferably the storage modulus G'(120° C.) of the toner at 120° C. The ratios of the storage moduli GA / GB, G1 / G2, and G3 / G2 are preferably 1.1 to 4.0, more preferably 1.2 to 3.0, and even more preferably 1.4 to 2.5. By being within the above ranges, higher adhesive strength is likely to be obtained.

[0071] As long as GA>GB, G1>G2, and G3>G2 are satisfied, GA, G1, and G3 (preferably G'(120°C)) are not particularly limited. 4 ~3. 5×10 4 Pa is preferred, 1.5×10 4 ~3.0×10 4 Pa is more preferable, 1.8×10 4 ~2.7×10 4 In addition, GB and G2 (preferably G'(120°C)) are not particularly limited, but each is preferably 0.5 x 10 4 ~2.5×10 4 P a is preferred, 1.0×10 4 ~2.0×10 4 Pa is more preferable, and 1.0×10 4 ~1.8×10 4 More preferably, the storage modulus is 1 Pa. The storage modulus can be controlled by the amount of a crosslinking agent and an amount of a polymerization initiator used in the toner.

[0072] <Toner composition and manufacturing method> The configuration of the toners Ty, Tm, Tc, and Tk that are used for both printing and adhesion will be described. For example, the toners Ty, Tm, Tc, and Tk that contain a thermoplastic resin as a binder resin can be used. Resins that can be used as the thermoplastic resin are not particularly limited, and examples of known thermoplastic resins include polyester resins, vinyl resins, acrylic resins, styrene-acrylic resins, polyethylene, polypropylene, polyolefins, ethylene-vinyl acetate copolymer resins, and ethylene-acrylic acid copolymer resins. A plurality of these resins may be included.

[0073] The toner preferably contains a polyester resin or a vinyl resin. The vinyl resin more preferably contains a styrene-acrylic resin such as a styrene-methyl acrylate copolymer, a styrene-ethyl acrylate copolymer, a styrene-butyl acrylate copolymer, a styrene-octyl acrylate copolymer, a styrene-dimethylaminoethyl acrylate copolymer, a styrene-methyl methacrylate copolymer, a styrene-ethyl methacrylate copolymer, a styrene-butyl methacrylate copolymer, or a styrene-dimethylaminoethyl methacrylate copolymer, and further preferably contains a styrene-butyl acrylate copolymer.

[0074] The polyester resin may be a condensation polymer of a carboxylic acid component and an alcohol component as listed below. Examples of the carboxylic acid component include terephthalic acid, isophthalic acid, phthalic acid, fumaric acid, maleic acid, cyclohexanedicarboxylic acid, and trimellitic acid. Examples of the alcohol component include bisphenol A, hydrogenated bisphenol, an ethylene oxide adduct of bisphenol A, a propylene oxide adduct of bisphenol A, glycerin, trimethylolpropane, and pentaerythritol.

[0075] The thermoplastic resin may contain a polyester resin in addition to the vinyl resin. The content of the vinyl resin in the thermoplastic resin is preferably 50 to 100% by mass, more preferably 80 to 99% by mass, and further preferably 90 to 98% by mass. The method for producing the polymer is not particularly limited, and any known method can be used.

[0076] The toners Ty, Tm, Tc, and Tk preferably further contain a wax. As the wax, known waxes such as ester waxes which are esters of alcohol and acid, and hydrocarbon waxes such as paraffin wax can be used.

[0077] The toners Ty, Tm, Tc, and Tk each contain a colorant. The colorant is, for example, yellow. Known colorants can be used for the toner Ty, such as a yellow colorant, the magenta toner Tm, the cyan toner Tc, and the black toner Tk, such as a black colorant.

[0078] The toners Ty, Tm, Tc, and Tk may contain a magnetic material, a charge control agent, a wax, and an external additive. The toner may have a crosslinked structure. The crosslinked structure is formed by a crosslinking agent having a plurality of vinyl groups, such as divinylbenzene. The crosslinking agent is not particularly limited, and a known crosslinking agent may be used. The storage modulus of the toner can be controlled by the amount of the crosslinking agent.

[0079] In order to form an adhesive layer of toners Ty, Tm, Tc, and Tk on a sheet using an electrophotographic method, the volume average particle diameter of the toners Ty, Tm, Tc, and Tk is preferably 5.0 μm or more and 30 μm or less, and more preferably 6.0 μm or more and 20 μm or less. Moreover, general printing toners may be used as the toners Ty, Tm, Tc, and Tk as long as they satisfy the adhesive property.

[0080] 4A is a schematic diagram showing a printing area S of an adhesive image pattern using toners Ty, Tm, Tc, and Tk in an embodiment described later. As shown by the hatched area, the printing area S of the adhesive image pattern is image-formed at the end of the long side of the sheet P, making it possible to produce a long bound booklet as an end product when the booklet is produced by the post-processing device. Here, in the embodiment described later, the width W of the printing area S of the adhesive image pattern is set to 4.0 mm. The shape of the printing area S may be appropriately changed so as to obtain a desired booklet. As shown in FIG. 4B, by forming the printing area S of the adhesive image pattern on a part of the long side end, it is also possible to produce a corner-fastened booklet as the final product. In the examples described later, the toner amount (laying amount) per unit area of ​​each single toner color used in the adhesive image pattern is 0.4 mg / cm. 2 It was decided.

[0081] For example, the toner amount on each sheet of the toner forming the adhesive layer is 0.3 to 1.5 mg / cm 2 is preferably 0.4 to 1.0 mg / cm 2 The total amount of toner in the adhesive image pattern is preferably 0.8 to 2.0 mg / cm. 2 is preferably 1.0 to 1.5 mg / cm 2 is more preferred.

[0082] The following describes the manufacturing examples of toners Ty, Tm, Tc, and Tk. In the examples, the toners manufactured as follows were used. In each toner, the following colorant was used. Toner Ty: CI Pigment Yellow 12 Toner Tm: CI Pigment Red 254 Toner Tc: Copper phthalocyanine Toner Tk: Carbon black

[0083] Styrene 75.0 parts n-Butyl acrylate 25.0 parts Polyester resin 4.0 parts (Weight average molecular weight (Mw) 20,000, glass transition temperature (Tg) 75°C, acid value 8.2 mgKOH / g polyester resin (bisphenol A-propylene oxide 2.0 mole adduct and terephthalic acid used in a 1:1 molar ratio) Colorant 6.5 parts Ethylene glycol distearate 14.0 parts (Ester wax made by esterifying ethylene glycol and stearic acid) Hydrocarbon wax (HNP-9, Nippon Seiro) 2.0 parts Divinylbenzene (crosslinking agent) 0.5 parts The mixture of the above materials was kept at 60° C. and stirred at 500 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) to dissolve uniformly, thereby preparing a polymerizable monomer composition.

[0084] Meanwhile, 0.10 mol / L-Na was added to a vessel equipped with a high-speed stirring device Clearmix (M Technique Co., Ltd.). 3 PO 4 850.0 parts of the aqueous solution and 8.0 parts of 10% hydrochloric acid were added, the rotation speed was adjusted to 15,000 rpm, and the mixture was heated to 70°C. 2 127.5 parts of the aqueous solution was added to prepare an aqueous medium containing a calcium phosphate compound.

[0085] After the polymerizable monomer composition was added to the aqueous medium, 7.0 parts of t-butyl peroxypivalate, a polymerization initiator, was added, and the mixture was granulated for 10 minutes while maintaining a rotation speed of 15,000 rpm. After that, the high-speed agitator was replaced with a propeller agitator, and the mixture was reacted at 70°C for 5 hours under reflux, and then the liquid temperature was increased to 85°C and the mixture was reacted for another 2 hours.

[0086] After the polymerization reaction was completed, the resulting slurry was cooled, and then hydrochloric acid was added to the slurry to adjust the pH to 1.4 and the slurry was stirred for 1 hour to dissolve the calcium phosphate salt.The slurry was then washed with three times the amount of water, filtered, dried, and classified to obtain toner particles.

[0087] Thereafter, silica fine particles (number average particle diameter of primary particles: 10 nm, BET specific surface area: 170 m) that had been hydrophobized using dimethyl silicone oil (20% by mass) were added to 100.0 parts of the adhesive toner particles as an external additive. 2 The mixture was mixed at 3000 rpm for 15 minutes using a Mitsui Henschel mixer (manufactured by Mitsui Miike Chemical Engineering Co., Ltd.) to obtain toners Ty, Tm, Tc, and Tk. The volume average particle diameter of the obtained toners Ty, Tm, Tc, and Tk was all 7.0 μm.

[0088] <About the viscoelastic properties of toner> The method for measuring the storage modulus as a viscoelastic property of the toner will be described below. The storage modulus of the toner Ty, Tm, Tc, and Tk is measured using a dynamic viscoelasticity measuring device (rheometer) ARES (manufactured by Rheometrics Scientific). Measurement jig: Use a serrated parallel plate with a diameter of 7.9 mm. Measurement sample: Using a pressure molding machine, mold a cylindrical sample with a diameter of 8 mm and a height of 2 mm from a 0.1 g sample (pressure conditions: maintain 15 kN for 1 minute at room temperature). The pressure molding machine used is a 100 kN press NT-100H manufactured by NPa Systems. The temperature of the serrated parallel plate is adjusted to 120°C, the cylindrical sample is heated and melted, the sawtooth is inserted, and a load is applied vertically so that the axial force does not exceed 30 (gf) (0.294N) to fix it to the serrated parallel plate. A steel belt may be used at this time so that the diameter of the sample is the same as that of the parallel plate. The serrated parallel plate and the cylindrical sample are slowly cooled down to the measurement start temperature of 30.00°C over one hour. Measurement frequency: 6.28 rad / sec Measurement distortion setting: Set the initial value to 0.1%, and perform the measurement in automatic measurement mode. Sample elongation correction: Adjusted in automatic measurement mode. Measurement temperature: 30°C to 140°C at a rate of 2°C per minute. Measurement interval: Measure viscoelastic data every 30 seconds, i.e., every 1°C.

[0089] Toners having different storage moduli were produced by the above-mentioned toner manufacturing method, and toner set A used in Example 1, toner set B used in Comparative Example 1, and toner set C used in Comparative Example 2 were obtained. The storage moduli of the toners were changed by adjusting the amount of crosslinking agent in the above-mentioned toner manufacturing method as follows.

[0090] (Toner Set A) Ty: 0.7 parts Tm: 0.6 parts Tc: 0.5 parts Tk: 0.8 parts

[0091] (Toner Set B) Ty: 0.8 parts Tm: 0.8 parts Tc: 0.8 parts Tk: 0.8 parts

[0092] (Toner Set C) Ty: 0.5 parts Tm: 0.5 parts Tc: 0.5 parts Tk: 0.5 parts

[0093] In this embodiment, when the thermocompression bonding unit 51 bonds a stack of sheets, the peak temperature of the bonding image pattern (adhesive layer) when bonding a maximum of five sheets at once is set to 120° C. In detail, as shown in FIG. 3A, the surface temperature of the heating plate 502 and the set temperature of the temperature detection means are set so that the temperature of the bonding image pattern (adhesive layer) between P1-4 and P1-5 is 120° C. when bonding P1-1 to P1-5 at once.

[0094] The temperature of the adhesive image pattern (adhesive layer) was measured by attaching a thermocouple with a small heat capacity (for example, a K-type thermocouple wire with a diameter of 50 μm or less, manufactured by Anritsu Meter Co., Ltd.) to the location corresponding to the printing area S of the adhesive layer between P1-4 and P1-5 in FIG. 3A. The peak value of the temperature of the adhesive image pattern (adhesive layer) during the bonding operation by the thermocompression bonding unit 51 was obtained by measuring the potential difference signal from the thermocouple with a memory high-corder manufactured by HIOKI EE (time resolution set to 0.1 sec). When performing this measurement, the same measurement was performed five times, and the average value of the three measurements excluding the top and bottom temperatures was used as the peak value of the temperature of the adhesive image pattern (adhesive layer).

[0095] The peak temperature of the adhesive image pattern (adhesive layer) is preferably set based on the adhesiveness of the toner. Specifically, it is more preferable to set the peak temperature based on the adhesiveness of the toner that is least likely to melt under the heating and pressurizing conditions (heating temperature, pressure, and pressurizing time) of the thermocompression unit 51.

[0096] Fig. 5 is an example of the measurement results of the storage modulus of the toner. From the measurement results of the toner viscoelasticity shown in Fig. 5, the storage modulus G'(120°C) of the toner at 120°C, which corresponds to the peak value of the temperature of the adhesive image pattern (adhesive layer) in this embodiment, can be obtained. In the case of Fig. 5, G'(120°C) = 1.1 x 10 4 It becomes Pa.

[0097] Table 1 shows the storage elastic modulus G' (120°C) values ​​of the yellow toner Ty, magenta toner Tm, cyan toner Tc, and black toner Tk of the toner set A used in Example 1, the toner set B used in Comparative Example 1, and the toner set C used in Comparative Example 2. [Table 1]

[0098] In the toner set A used in Example 1, the storage modulus G' (12 On the other hand, in the toner set B used in Comparative Example 1, the storage modulus G' (120°C) of the four color toners was set to the same value (2.5×10 4 Similarly, in the toner set C used in Comparative Example 2, the storage modulus G' (120°C) of the four color toners was set to the same value (1.1 × 10 4 The temperature is set to 100 Pa.

[0099] <Results of a comparative experiment on booklet adhesive strength> Table 2 shows the results of a comparative experiment using Toner Set A, Toner Set B, and Toner Set C shown in Table 1. Through this comparative experiment, we investigated the relationship between the toner used, the type of toner used in the adhesive layer, and the resulting booklet adhesive strength. The recording material P used in this measurement is Vitality Multipurpose Printer Paper (Xerox) with an LTR size (279 mm x 216 mm) and a basis weight of 90 g / m 2 "

[0100] The method for evaluating the booklet adhesive strength will be described with reference to the schematic diagrams of Figures 6A and 6B. First, five booklets were produced as shown in Figure 3A using the image forming apparatus 1 and thermocompression bonding unit 51 shown in Figure 1. At this time, the thermocompression bonding unit produced booklets for strength testing in a single heating and pressure treatment.

[0101] After that, P1-1 to P1-3 were peeled off and removed from the obtained booklet, leaving two booklets with only P1-4 and P1-5 bonded together. Then, the two booklets consisting of P1-4 and P1-5 were cut out to have dimensions of width (H) 20 mm and length (L) 50 mm as shown in Figure 6A to prepare test piece E including the bonded part S. Next, as shown in Figure 6B, the P1-4 side of this test piece E was held by an upper holding member, and the P1-5 side was held by a lower holding member. A digital force gauge M (Nidec-Shimpo Corporation, FGP-2) was also connected to the upper holding member. The digital force gauge was then gradually raised upward, and the peel force when the adhesive part S peeled off was measured by the digital force gauge, and the peak peel force value was recorded. Each measurement was performed five times, and the average value was taken as the booklet adhesive strength of the adhesive part S. The authors' investigation confirmed that, in practical terms, the adhesive strength of the booklet is desirable to be 1.0 N / cm or more per unit distance in the width direction of the test piece, so they decided that a booklet strength of 1.0 N / cm or more is OK as a quality standard, and anything less is NG as a booklet strength. The reason for measuring the adhesive strength between P1-4 and P1-5 is that this is the area farthest from the heating plate compared to the other adhesive areas, making it difficult to supply heat to and therefore making it an area where the booklet adhesive strength is likely to be an issue.

[0102] The results of a comparative experiment on the booklet adhesive strength using toner set A, toner set B, and toner set C shown in Table 1 will be described with reference to Table 2. [Table 2]

[0103] Example 1 In Example 1, toner set A shown in Table 1 was used. The lamination pattern of the toner used in the adhesive layer will be described with reference to FIG. 7. This indicates that the adhesive layer was formed on the sheet in the order of the toners listed in Table 2. For example, "black, cyan" indicates that the sheet, the adhesive layer of the black toner, and the adhesive layer of the cyan toner were formed in this order. Also, "black, cyan, magenta" indicates that the sheet, the adhesive layer of the black toner, the adhesive layer of the cyan toner, and the adhesive layer of the magenta toner were formed in this order.

[0104] In FIG. 7A, black toner Tk and cyan toner Tc are laminated on the adhesive layer on the front surface of the sheet (P1-5 side) (i.e., one of the two opposing sheets), and only black toner Tk is laminated on the adhesive layer on the back surface of the sheet (P1-4 side) (i.e., the other of the two opposing sheets). As shown in Figure 3A, during the adhesive treatment, the adhesive layer on the front side of the sheet faces the adhesive layer on the back side of the sheet. In the laminated pattern of the adhesive layers in Example 1 in Table 2, FIG. 7A, the booklet adhesive strength was 1.3 N / cm, and sufficient adhesive strength was ensured for booklet quality.

[0105] In Fig. 7B, black toner Tk and cyan toner Tc are laminated on the adhesive layer on the front surface of the sheet (P1-5 side), and black toner Tk and cyan toner Tc are similarly laminated on the adhesive layer on the back surface of the sheet (P1-4 side). The lamination order is as shown in Fig. 7B during the adhesion process. In Fig. 7B, which shows the adhesive layer lamination pattern in Example 1 of Table 2, the booklet adhesive strength was 1.5 N / cm, and sufficient adhesive strength was ensured for booklet quality.

[0106] In Fig. 7C, black toner Tk, cyan toner Tc, and magenta toner Tm are laminated on the adhesive layer on the front surface of the sheet (P1-5 side), and black toner Tk is laminated on the adhesive layer on the back surface of the sheet (P1-4 side). The lamination order is as shown in Fig. 7C during the adhesion process. In Fig. 7C, which shows the adhesive layer lamination pattern in Example 1 of Table 2, the booklet adhesive strength was 1.5 N / cm, which was sufficient for booklet quality.

[0107] Comparative Example 1 Comparative Example 1 used toner set B shown in Table 1. The lamination pattern of the toner used in the adhesive layer is the same as that of Example 1 in Table 2 described above, as shown in Figs. 7A to 7C, and therefore a description thereof will be omitted. In the laminated pattern of the adhesive layer in Comparative Example 1 in Table 2, Fig. 7A, the booklet adhesive strength was 0.5 N / cm, and the adhesive strength was insufficient for booklet quality. Similarly, in the laminated patterns of the adhesive layer in Comparative Example 1 in Table 2, Fig. 7B and Fig. 7C, the booklet adhesive strength was both 0.7 N / cm, and the adhesive strength was insufficient for booklet quality.

[0108] Comparative Example 2 Comparative Example 2 used toner set C shown in Table 1. The lamination pattern of the toner used in the adhesive layer is the same as that of Example 1 in Table 2 described above, as shown in Figs. 7A to 7C, and therefore a description thereof will be omitted. In the laminated pattern of the adhesive layer in Comparative Example 2 in Table 2, Fig. 7A, the booklet adhesive strength was 0.4 N / cm, and the adhesive strength was insufficient for booklet quality. Similarly, in the laminated patterns of the adhesive layer in Comparative Example 2 in Table 2, Fig. 7B and Fig. 7C, the booklet adhesive strength was both 0.7 N / cm, and the adhesive strength was insufficient for booklet quality.

[0109] <Mechanism of booklet adhesive strength development> While a sufficient booklet adhesive strength was ensured in Example 1 in Table 2, the booklet adhesive strength was insufficient in Comparative Examples 1 and 2 in Table 2. The mechanism by which these three differences emerge will be explained using the schematic diagrams of Figures 8A, 8B, and 8C.

[0110] 8A is a schematic diagram showing a cross-sectional state of the toner after the adhesion process in FIG. 7A, which shows the laminated pattern of the adhesive layer in Example 1 in Table 2. Referring to the toner set A in Table 1 used in Example 1, the storage elastic modulus G' (120° C.) of the black toner Tk forming the adhesive layer adjacent to the sheet P1-5 and the sheet P1-4 in FIG. 8A is larger than that of the other color toners in the toner set A. - is higher.

[0111] Usually, the temperature and pressure during the adhesion process are set to ensure the adhesiveness of the toner that is least likely to melt. For example, in the case of toner set A, the black toner Tk with the highest storage modulus G' (120°C) is used as the standard. In such a case, FIG. As shown in FIG. 1, the black toner Tk does not soak into the sheet, and the thickness of the adhesive layer can be secured. In this embodiment, the thicker the adhesive layer, the better the booklet adhesion. Strength is gained.

[0112] In the case of toner set A, the storage modulus G'(1 The storage modulus G' (20°C) of the black toner is lower than that of the black toner (120°C). In such a case, the cyan toner Tc is easily melted and deformed, and therefore easily follows the surface shape of the black toner Tk. In other words, it is possible to reduce voids at the interface between the toner adhesive layers, and to suppress cohesive failure at the interface of the adhesive layers. In Example 1, it is believed that good booklet adhesive strength was obtained by adjusting the viscoelastic properties between the toners in this way.

[0113] It is believed that a similar mechanism led to good booklet adhesive strength in the laminate patterns of the adhesive layers in Figures 7B and 7C in Example 1 of Table 2. It is believed that the booklet adhesive strength is slightly higher in Figures 7B and 7C because the total amount of toner used in the adhesive layers is greater than that in Figure 7A.

[0114] FIG. 8B is a schematic diagram showing the cross-sectional state of the toner after the adhesion treatment in FIG. 7A of the laminated pattern of the adhesive layer in Comparative Example 1 shown in Table 2. The storage modulus G' (120° C.) of the toner set B in Comparative Example 1 shown in Table 1 is the same for all four colors (Ty, Tm, Tc, Tk) as described above. The storage modulus G' was adjusted to be equal to the highest Tk in toner set A. The temperature and pressure during adhesion and fixing processes of toner set B were set equal to those of toner set A in Example 1.

[0115] As shown in FIG. 8B, the black toner Tk has the same storage modulus G' (120 The adhesive layer is adjusted to a temperature of 120°C, so that the adhesive layer does not penetrate the sheet and the thickness of the adhesive layer can be secured. 0°C) is as high as the storage modulus G' (120°C) of the black toner. In such a case, the cyan toner Tc is difficult to melt and deform, and therefore difficult to follow the surface shape of the black toner Tk. In other words, the number of voids increases at the interface between the toner adhesive layers, which makes it easier for cohesive failure to occur at the interface of the adhesive layers, and the booklet adhesive strength decreases. As a result of these actions, it is believed that the booklet adhesive strength is insufficient in the laminated pattern of the adhesive layers in Comparative Example 1 in Table 2 (Figure 7A). It is believed that the booklet adhesive strength also decreased due to the same mechanism in the laminate patterns of the adhesive layers in Comparative Example 1 of Table 2, FIGS. 7B and 7C.

[0116] FIG. 8C is a schematic diagram showing the cross-sectional state of the toner after the adhesion treatment in the laminated pattern of the adhesive layer in FIG. 7A in Comparative Example 2 shown in Table 2. The storage modulus G' (120° C.) of the toner set C in Comparative Example 2 shown in Table 1 is the same for all four colors (Ty, Tm, Tc, Tk) as described above. The storage modulus G' was adjusted to be equal to the lowest Tc among the toner set A. The temperature and pressure during the adhesion process and fixing process of the toner set C were set equal to those of the toner set A in the first embodiment.

[0117] As shown in FIG. 8C, the black toner Tk has a lower storage modulus G' (12 0℃), so it is easy for the liquid to penetrate into the sheet. Because pressure is easily applied during the adhesion and fixing processes, the toner seeps in significantly, causing the adhesive layer to become thinner. When the adhesive layer becomes thinner, it becomes easier for the adhesive layer to be locally absent in areas such as paper convexities. In other words, the adhesive area between the sheet and the adhesive layer becomes smaller, making it easier for them to peel off, and reducing the adhesive strength of the booklet. It is believed that these actions resulted in insufficient booklet adhesive strength in the adhesive layer lamination pattern of FIG. 7A in Comparative Example 2 in Table 2. It is believed that the booklet adhesive strength also decreased due to the same mechanism in the adhesive layer lamination patterns of FIG. 7B and FIG. 7C in Comparative Example 2 in Table 2. do.

[0118] As described above, in the present disclosure, when forming an adhesive layer using a plurality of toners, the storage modulus of the toner adjacent to the sheet is made higher than the storage modulus of the toner not adjacent to the sheet. In other words, by selecting the toner used in the adhesive image pattern so as to satisfy the above-mentioned GA>GB, G1>G2, and G3>G2, it is possible to obtain good booklet adhesive strength.

[0119] Here, in Example 1 of Table 2, the type of toner used in the adhesive layer is specified, but as long as the storage modulus of the toner adjacent to the sheet is higher than the storage modulus of the toner not adjacent to the sheet, good booklet adhesive strength can be obtained. This is because, as mentioned above, the temperature and pressure settings during the adhesive process are usually determined based on the adhesiveness of the toner that is least likely to melt.

[0120] For example, in the laminated adhesive layer patterns of FIG. 7A and FIG. 7B in Example 1 of Table 2, magenta toner Tm or yellow toner Ty may be used instead of cyan toner Tc. Also, in the laminated adhesive layer pattern of FIG. 7C, the types of toner of cyan toner Tc and magenta toner Tm sandwiched between black toner Tk and the number of toner layers may be changed. In toner set A of Table 1, the storage elastic modulus of black toner Tk is higher than that of other toners, so that the toner that can be laminated between black toner Tk can be freely selected from among cyan toner Tc, magenta toner Tm, and yellow toner Ty, and good booklet adhesive strength can be obtained in any case.

[0121] In this embodiment, the post-processing device having the thermocompression bonding unit is arranged next to the image forming device 1, but this is not limited to this. For example, the thermocompression bonding unit 51 may be arranged on the top of the image forming device main body as shown in Figure 9.

[0122] Example 2 In the second embodiment, it is shown that an image forming apparatus having good booklet adhesive strength is provided even if the toner adjacent on the front surface of the sheet and the toner adjacent on the back surface of the sheet are different types after the booklet is bonded. By changing the type of toner used, it is possible to suppress an increase in the consumption of a specific toner. In addition, depending on the lamination pattern of the toner used in the adhesive layer, it is possible to obtain good booklet adhesive strength even in single-sided printing, and booklet productivity can be improved.

[0123] The basic configurations and operations of the image forming apparatus and post-processing apparatus of this embodiment are the same as those of the image forming apparatus and post-processing apparatus of the above-mentioned embodiment 1. Therefore, in the image forming apparatus and post-processing apparatus of this embodiment, elements having the same or corresponding functions or configurations as those of the image forming apparatus and post-processing apparatus of embodiment 1 are given the same reference numerals as those of embodiment 1, and detailed explanations are omitted.

[0124] The booklet adhesive strength in Example 2 will be described with reference to Table 3. [Table 3]

[0125] In Example 2, the same toner set A in Table 1 as in Example 1 was used. The lamination pattern of the toner used in the adhesive layer will be described with reference to Figures 10A to 10C.

[0126] In Fig. 10A, black toner Tk and cyan toner Tc are laminated on the adhesive layer on the front surface of the sheet (P1-5 side), and only yellow toner Ty is laminated on the adhesive layer on the back surface of the sheet (P1-4 side). In Fig. 10A, which shows the laminate pattern of the adhesive layer in Example 2 in Table 3, the booklet adhesive strength was 1.2 N / cm, which was sufficient for booklet quality. Referring to toner set A in Table 1, the storage modulus G' (120°C) of the black toner Tk adjacent to sheet P1-5 and the yellow toner Tk adjacent to sheet P1-4 in FIG. 10(a) is higher than the storage modulus G' (120°C) of the cyan toner Tc sandwiched between them. Therefore, it is considered that good booklet adhesive strength can be obtained for the same reason as the adhesion mechanism explained in FIGS. 8A to 8C. Furthermore, compared to the lamination pattern in FIG. 7A of Example 1, the consumption of black toner Tk is reduced by one time, so it is possible to suppress an increase in the consumption of a specific toner.

[0127] In FIG. 10B, the adhesive layer stacking order is the same as in FIG. 10A, but the adhesive layer is formed only on the front surface of the sheet by single-sided printing. By not printing on both sides, it is possible to improve booklet productivity. Black toner Tk, cyan toner Tc, and yellow toner Ty are stacked on the adhesive layer on the front surface of the sheet (P1-5 side), and no adhesive layer is provided on the back surface of the sheet (P1-4 side). During the adhesive process, the adhesive image pattern has the stacking order shown in FIG. 10B. In FIG. 10B, which shows the adhesive layer stacking pattern in Example 2 of Table 3, the booklet adhesive strength was 1.2 N / cm, and sufficient adhesive strength was ensured for booklet quality. As a result, the adhesive image patterns in FIG. 10A and FIG. 10B have the same toner layer configuration, and therefore have the same booklet adhesive strength.

[0128] In FIG. 10C, black toner Tk, cyan toner Tc, magenta toner Tm, and yellow toner Ty are all laminated on the adhesive layer on the front surface of the sheet (P1-5 side), and no adhesive layer is provided on the back surface of the sheet (P1-4 side). The lamination order is as shown in FIG. 10C during the adhesion process. In FIG. 10C, which shows the adhesive layer lamination pattern in Example 2 of Table 3, the booklet adhesive strength is 1.3 N / cm, and sufficient adhesive strength is ensured for booklet quality. In the case of FIG. 10C, the total amount of toner used in the adhesive layer is greater than that of FIG. 10B, so the booklet adhesive strength is slightly higher.

[0129] As described above, according to this embodiment, a toner layer for adhesion is formed using a plurality of toners. In the case of forming the booklet, it is possible to obtain a good booklet adhesive strength while suppressing the consumption amount of the specific toner.

[0130] Here, in Example 2 of Table 3, the type of toner used in the adhesive layer is specified, but as in the case of Example 1, good booklet adhesive strength can be obtained as long as the storage modulus of the toner adjacent to the sheet is higher than the storage modulus of the toner not adjacent to the sheet. In the second embodiment, similarly to the first embodiment, the thermocompression bonding unit 51 may be disposed on the upper portion of the main body of the image forming apparatus as shown in FIG.

[0131] In the first and second embodiments, the toner amount may be changed depending on the number and type of toner used in the adhesive layer. For example, the toner consumption can be reduced by reducing the toner amount within the range where the booklet quality of the adhesive strength is maintained. The preferable range of the toner amount is as described above. In this case, the adhesive conditions (temperature setting, pressure setting, pressure time) of the post-processing device may be changed depending on the amount of toner applied to the adhesive layer. That is, the adhesive conditions are at least one selected from the temperature setting, pressure setting, and pressure time. For example, if the amount of toner applied is small, the temperature setting can be lowered, the pressure setting can be lowered, and the pressure time can be shortened. By optimizing the adhesive conditions, further improvement in booklet quality can be expected.

[0132] The present disclosure relates to the following configurations and methods. (Configuration 1) An image forming apparatus, The image forming apparatus includes at least a first image forming means for forming a first adhesive layer on a sheet by a first toner; a second image forming means for forming a second adhesive layer on the first adhesive layer by a second toner; an adhesive image pattern is formed by the first adhesive layer and the second adhesive layer; the image forming apparatus has a booklet bonding means for stacking a plurality of the sheets to form a sheet bundle, and bonding the sheets together via the bonding image pattern by applying heat and pressure to the sheet bundle to form a booklet; In the sheet bundle, at least both the first adhesive layer and the second adhesive layer are formed on one of the opposing first sheet and second sheet, At least the first adhesive layer is formed on the other side, When the storage modulus of the first toner forming the first adhesive layer is G1 and the storage modulus of the second toner forming the second adhesive layer is G2, The image forming apparatus is characterized in that G1 and G2 satisfy G1>G2. (Configuration 2) An image forming apparatus, The image forming apparatus includes at least a first image forming means for forming a first adhesive layer on a sheet by a first toner; a second image forming means for forming a second adhesive layer on the first adhesive layer using a second toner, and a third image forming means for forming a third adhesive layer using a third toner; an adhesive image pattern is formed by the first adhesive layer, the second adhesive layer and the third adhesive layer; the image forming apparatus has a booklet bonding means for stacking a plurality of the sheets to form a sheet bundle, and bonding the sheets together via the bonding image pattern by applying heat and pressure to the sheet bundle to form a booklet; In the sheet bundle, one of the opposing first sheet and second sheet has both the first adhesive layer and the second adhesive layer formed thereon; At least the third adhesive layer is formed on the other side, When the storage elastic modulus of the first toner forming the first adhesive layer is G1, the storage elastic modulus of the second toner forming the second adhesive layer is G2, and the storage elastic modulus of the third toner forming the third adhesive layer is G3, The image forming apparatus, wherein G1, G2 and G3 satisfy G1>G2 and G3>G2. (Configuration 3) An image forming apparatus, The image forming apparatus includes: a first image forming means for forming a first adhesive layer on a sheet by a first toner; a second image forming means for forming a second adhesive layer by a second toner on the first adhesive layer, a third image forming means for forming a third adhesive layer by a third toner on the second adhesive layer, and a fourth image forming means for forming a fourth adhesive layer by a fourth toner on the third adhesive layer, an adhesive image pattern is formed by at least three adhesive layers among the first adhesive layer, the second adhesive layer, the third adhesive layer, and the fourth adhesive layer; the image forming apparatus has a booklet bonding means for stacking a plurality of the sheets to form a sheet bundle, and bonding the sheets together via the bonding image pattern by applying heat and pressure to the sheet bundle to form a booklet; In the sheet bundle, all of the adhesive image patterns are formed on one of the opposing first sheet and second sheet, In the sheet bundle, among the at least three adhesive layers forming the adhesive image pattern, the storage elastic modulus of the toner forming the adhesive layer A adjacent to the sheet is defined as GA, and the storage elastic modulus of the toner forming the adhesive layer B other than the adhesive layer A is defined as GB. The image forming apparatus is characterized in that the GA and GB satisfy GA>GB. (Configuration 4) 4. The image forming apparatus according to any one of configurations 1 to 3, wherein the temperature at which the storage elastic modulus is measured is a peak value of the temperature of the adhesive image pattern during operation of the booklet bonding means. (Configuration 5) 5. The image forming apparatus according to any one of Configurations 1 to 4, wherein the temperature for measuring the storage elastic modulus is 120°C. (Configuration 6) 2. The image forming apparatus according to claim 1, wherein the first toner is a black toner. (Configuration 7) 7. The image forming apparatus according to claim 6, wherein the second toner is at least one selected from the group consisting of a yellow toner, a magenta toner, and a cyan toner. (Configuration 8) 3. The image forming apparatus according to claim 2, wherein the first toner is a black toner. (Configuration 9) 9. The image forming apparatus according to claim 8, wherein the second toner is at least one selected from the group consisting of a magenta toner and a cyan toner. (Configuration 10) 10. The image forming apparatus of claim 9, wherein the third toner is a yellow toner. (Configuration 11) the first toner is a black toner, the second toner is one of a magenta toner and a cyan toner, the third toner is the other of the magenta toner and the cyan toner, 4. The image forming apparatus according to claim 3, wherein the fourth toner is a yellow toner. (Configuration 12) The total amount of toner in the adhesive image pattern is 0.8 to 2.0 mg / cm 2 12. The image forming apparatus according to any one of Configurations 1 to 11, (Configuration 13) 13. The image forming apparatus according to any one of configurations 1 to 12, wherein the bonding conditions of the booklet bonding means are changed according to the amount of applied toner. (Configuration 14) 14. The image forming apparatus according to claim 13, wherein the adhesion condition is at least one selected from a temperature setting, a pressure setting, and a pressure application time. (Configuration 15) An image forming apparatus, The image forming apparatus includes: an image forming means for forming an adhesive image pattern including an adhesive layer made of toner on a sheet; a booklet bonding means for stacking a plurality of the sheets on which the adhesive image pattern is formed to form a sheet bundle, and bonding the sheets together via the adhesive image pattern by heating and pressurizing the sheet bundle to form a booklet, the adhesive image pattern has at least three adhesive layers formed by the toner, The at least three adhesive layers are formed using different toners, In the sheet bundle, among the at least three adhesive layers forming the adhesive image pattern, the elastic modulus of the toner forming the adhesive layer A adjacent to the sheet is defined as GA, and the elastic modulus of the toner forming the adhesive layer B other than the adhesive layer A is defined as GB. The image forming apparatus is characterized in that the GA and GB satisfy GA>GB. (Method 16) A booklet production method, comprising the steps of: The booklet production method includes: forming an adhesive image pattern including an adhesive layer made of toner on a sheet by an image forming means; and a booklet bonding means for stacking a plurality of the sheets on which the adhesive image pattern is formed to form a sheet bundle, and bonding the sheets together via the adhesive image pattern by heating and pressurizing the sheet bundle to form a booklet. In the adhesive image pattern, at least three adhesive layers are formed by the toner, The at least three adhesive layers are formed using different toners, In the sheet bundle, among the at least three adhesive layers forming the adhesive image pattern, the elastic modulus of the toner forming the adhesive layer A adjacent to the sheet is defined as GA, and the elastic modulus of the toner forming the adhesive layer B other than the adhesive layer A is defined as GB. A booklet production method, characterized in that the GA and GB satisfy GA>GB. [Explanation of symbols]

[0133] 1 . . . image forming apparatus, 1e . . . image forming unit, 2 . . . scanner unit, 3 . . . Transfer unit, 3a...transfer belt, 7...process cartridge, 8...sheet cassette, 19...casing, 20...multi-tray, 5...secondary transfer roller, 6...fuser, 5n...transfer nip, 6n...fuser nip, 25 . . . Upper paper output tray, 33 . . . Switching guide, 38 . . . Bundle output roller, 37 . . . Lower paper output tray, 42 . . . Intermediate stacking section, 51 . . . Thermocompression bonding unit, 200 . . . Intermediate transport unit 300 ... post-treatment device, D: Photosensitive drum, C: Charging roller, K: Toner storage compartment, P: Sheet

Claims

1. An image forming apparatus, The image forming apparatus includes at least a first image forming means for forming a first adhesive layer on a sheet by a first toner; a second image forming means for forming a second adhesive layer on the first adhesive layer by a second toner; an adhesive image pattern is formed by the first adhesive layer and the second adhesive layer; the image forming apparatus has a booklet bonding means for stacking a plurality of the sheets to form a sheet bundle, and bonding the sheets together via the bonding image pattern by applying heat and pressure to the sheet bundle to form a booklet; In the sheet bundle, at least both the first adhesive layer and the second adhesive layer are formed on one of the opposing first sheet and second sheet, At least the first adhesive layer is formed on the other side, When the storage modulus of the first toner forming the first adhesive layer is G1 and the storage modulus of the second toner forming the second adhesive layer is G2, The image forming apparatus is characterized in that G1 and G2 satisfy G1>G2.

2. An image forming apparatus, The image forming apparatus includes at least a first image forming means for forming a first adhesive layer on a sheet by a first toner; a second image forming means for forming a second adhesive layer on the first adhesive layer using a second toner, and a third image forming means for forming a third adhesive layer using a third toner; an adhesive image pattern is formed by the first adhesive layer, the second adhesive layer and the third adhesive layer; the image forming apparatus has a booklet bonding means for stacking a plurality of the sheets to form a sheet bundle, and bonding the sheets together via the bonding image pattern by applying heat and pressure to the sheet bundle to form a booklet; In the sheet bundle, one of the opposing first sheet and second sheet has both the first adhesive layer and the second adhesive layer formed thereon; At least the third adhesive layer is formed on the other side, When the storage elastic modulus of the first toner forming the first adhesive layer is G1, the storage elastic modulus of the second toner forming the second adhesive layer is G2, and the storage elastic modulus of the third toner forming the third adhesive layer is G3, The image forming apparatus is characterized in that G1, G2 and G3 satisfy G1>G2 and G3>G2.

3. An image forming apparatus, The image forming apparatus includes: a first image forming means for forming a first adhesive layer on a sheet by a first toner; a second image forming means for forming a second adhesive layer by a second toner on the first adhesive layer, a third image forming means for forming a third adhesive layer by a third toner on the second adhesive layer, and a fourth image forming means for forming a fourth adhesive layer by a fourth toner on the third adhesive layer, an adhesive image pattern is formed by at least three adhesive layers among the first adhesive layer, the second adhesive layer, the third adhesive layer, and the fourth adhesive layer; the image forming apparatus has a booklet bonding means for stacking a plurality of the sheets to form a sheet bundle, and bonding the sheets together via the bonding image pattern by applying heat and pressure to the sheet bundle to form a booklet; In the sheet bundle, the adhesive image pattern is applied to one of the opposing first and second sheets. All of the layers are formed, In the sheet bundle, of the at least three adhesive layers forming the adhesive image pattern, the storage elastic modulus of the toner forming the adhesive layer A adjacent to the sheet is defined as GA, and the storage elastic modulus of the toner forming the adhesive layer B other than the adhesive layer A is defined as GB. The image forming apparatus is characterized in that GA and GB satisfy GA>GB.

4. 4. The image forming apparatus according to claim 1, wherein the temperature at which the storage elastic modulus is measured is a peak value of the temperature of the adhesive image pattern during operation of the booklet bonding means.

5. 4. The image forming apparatus according to claim 1, wherein the storage elastic modulus is measured at a temperature of 120.degree.

6. 2. The image forming apparatus according to claim 1, wherein the first toner is a black toner.

7. 7. The image forming apparatus according to claim 6, wherein the second toner is at least one selected from the group consisting of a yellow toner, a magenta toner, and a cyan toner.

8. 3. The image forming apparatus according to claim 2, wherein the first toner is a black toner.

9. 9. The image forming apparatus according to claim 8, wherein the second toner is at least one selected from the group consisting of a magenta toner and a cyan toner.

10. 10. The image forming apparatus according to claim 9, wherein the third toner is a yellow toner.

11. the first toner is a black toner, the second toner is one of a magenta toner and a cyan toner, the third toner is the other of the magenta toner and the cyan toner, 4. The image forming apparatus according to claim 3, wherein the fourth toner is a yellow toner.

12. The total amount of toner in the adhesive image pattern is 0.8 to 2.0 mg / cm ２ 4. The image forming apparatus according to claim 1, wherein

13. 4. The image forming apparatus according to claim 1, wherein a bonding condition of said booklet bonding means is changed in accordance with the amount of said toner applied.

14. 14. The image forming apparatus according to claim 13, wherein the adhesion condition is at least one selected from a temperature setting, a pressure setting, and a pressure application time.

15. An image forming apparatus, The image forming apparatus includes: an image forming means for forming an adhesive image pattern including an adhesive layer made of toner on a sheet; a booklet bonding means for stacking a plurality of the sheets on which the adhesive image pattern is formed to form a sheet bundle, and bonding the sheets together via the adhesive image pattern by heating and pressurizing the sheet bundle to form a booklet, the adhesive image pattern has at least three adhesive layers formed by the toner, The at least three adhesive layers are formed from different toners, In the sheet bundle, of the at least three adhesive layers forming the adhesive image pattern, the storage elastic modulus of the toner forming the adhesive layer A adjacent to the sheet is defined as GA, and the storage elastic modulus of the toner forming the adhesive layer B other than the adhesive layer A is defined as GB. When I did, The image forming apparatus is characterized in that GA and GB satisfy GA>GB.

16. A booklet production method, comprising the steps of: The booklet production method includes: forming an adhesive image pattern including an adhesive layer made of toner on a sheet by an image forming means; and a booklet bonding means for stacking a plurality of the sheets on which the adhesive image pattern is formed to form a sheet bundle, and bonding the sheets together via the adhesive image pattern by heating and pressurizing the sheet bundle to form a booklet. In the adhesive image pattern, at least three adhesive layers are formed by the toner, The at least three adhesive layers are formed from different toners, In the sheet bundle, of the at least three adhesive layers forming the adhesive image pattern, the storage elastic modulus of the toner forming the adhesive layer A adjacent to the sheet is defined as GA, and the storage elastic modulus of the toner forming the adhesive layer B other than the adhesive layer A is defined as GB. A booklet production method, characterized in that GA and GB satisfy GA>GB.

Images