Water-based adhesive container

Abstract

To provide an aqueous adhesive container that can suppress the formation of aggregates of adhesive particles. [Solution] A water-based adhesive containing water and adhesive particles, applied to the surface of a transport member that transports a recording medium of a printing apparatus, and a container for containing the water-based adhesive, wherein the container has a container body made of a flexible sheet material that contains the water-based adhesive and has a mouth formed thereon, and a lid member that is attached to the mouth so as to be able to open and close the mouth, and when the ambient environment around the container is 25°C and 1 atm, let V1 be the volume of the water-based adhesive contained in the container and V2 be the volume of gas present in the container, the water-based adhesive container satisfies V2 / (V1+V2)×100≦18[vol%] in the initial unopened state of the container.

Description

[Technical Field]

[0001] This invention relates to an aqueous adhesive container. [Background technology]

[0002] For example, as shown in Patent Document 1, a printing apparatus is known that applies ink to a recording medium being transported on a conveyor belt to print a predetermined image pattern. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-89806 [Overview of the project] [Problems that the invention aims to solve]

[0004] An adhesive is applied to the surface of a conveying component such as a conveyor belt, and a dried adhesive layer is formed. The recording medium adheres to this adhesive layer, allowing the conveying component to hold and transport the recording medium. Generally, an adhesive containing an organic solvent is used as the adhesive applied to the conveying component. Therefore, careful consideration must be given to the handling of the adhesive during its manufacture and application to the conveying component. In particular, the application of the adhesive is subject to various constraints, such as ensuring sufficient ventilation, performing the application process quickly, and limiting the composition and amount of the organic solvent used. Therefore, the use of an aqueous adhesive containing water and adhesive particles is also being considered.

[0005] Incidentally, conventional adhesives using organic solvents were stored in hard metal containers such as 18-liter cans that were not affected by organic solvents. However, according to the inventors' research, when aqueous adhesives were stored in hard metal containers similar to those used for adhesives using organic solvents, it was found that over time, the adhesive particles tended to aggregate and form clumps. [Means for solving the problem]

[0006] The aqueous adhesive container according to the application example of the present invention contains water and adhesive particles, and an aqueous adhesive applied to the surface of a transport member that transports a recording medium of a printing device, a container that houses the aqueous adhesive, and is provided with The container is a container body that houses the aqueous adhesive and is composed of a flexible sheet material, and has a mouth formed therein, and a lid member that is detachably attached to the mouth at the mouth. It has When the ambient environment of the container is 25°C and 1 atm, the volume of the aqueous adhesive contained in the container is V1, and the volume of the gas present in the container is V2, the aqueous adhesive container is characterized in that it satisfies the following formula (1) in the initial state where the container is unopened. V2 / (V1 + V2)×100 ≦ 18 [vol%] ···(1)

Brief Description of Drawings

[0007] [Figure 1] It is a schematic configuration diagram showing a printing device according to an embodiment. [Figure 2] It is a diagram showing a state where a coating liquid of an aqueous adhesive is applied to the surface of a transport member of the printing device shown in FIG. 1. [Figure 3] It is a front view showing an aqueous adhesive container according to an embodiment. [Figure 4] It is a cross-sectional view taken along line IV-IV of FIG. 3. [Figure 5] It is an exploded perspective view showing a state before joining the ends of a pair of side sheets and a bottom sheet that constitute the container body of the aqueous adhesive container shown in FIG. 3. [Figure 6] It is a cross-sectional view showing a state where the volume of the aqueous adhesive in the container has decreased from the state of FIG. 4. [Figure 7] It is Table 1 showing the blending ratio and physical properties of (meth)acrylic monomers that constitute the adhesive particles of aqueous adhesive 1 and aqueous adhesive 2. [Figure 8]Table 2 shows the composition and evaluation of the aqueous adhesive containers of Examples 1 to 13 and Comparative Examples 1 and 2. [Modes for carrying out the invention]

[0008] Embodiments of the present invention will be described below with reference to the drawings. Note that the following description does not limit the technical scope or the meaning of terms as defined in the claims. Furthermore, the dimensional ratios in the drawings are exaggerated for illustrative purposes and may differ from actual ratios.

[0009] Figure 1 is a schematic diagram showing the printing apparatus 100 according to this embodiment. Figure 2 shows the state in which the coating liquid 12 of the aqueous adhesive 210 is applied to the surface 111s of the transport member 111 of the printing apparatus 100 shown in Figure 1. Figure 3 is a front view showing the aqueous adhesive container 200 according to this embodiment.

[0010] The aqueous adhesive container 200 shown in Figure 3 is used to store the aqueous adhesive 210 that is applied as a coating liquid 12 to the surface 111s of the transport member 111 of the printing apparatus 100 shown in Figures 1 and 2. Before describing the aqueous adhesive container 200, the printing apparatus 100 will be described first.

[0011] For the sake of explanation, the three mutually orthogonal axes shown in each figure are the x-axis, y-axis, and z-axis. The x-axis is an axis along one of the horizontal directions (the width direction of the transport member 111), the y-axis is an axis along the horizontal direction perpendicular to the x-axis (the direction of travel of the part of the transport member 111 that holds the recording medium W, which will be described later), and the z-axis is an axis along the vertical direction (up and down direction in the figure). In addition, the tip of each arrow shown is referred to as the "positive side (+ side)" and the base end as the "negative side (- side)". Furthermore, the z-axis direction + side is referred to as "up" or "upward", and the z-axis direction - side is referred to as "down" or "downward".

[0012] The printing apparatus 100, as outlined with reference to Figure 1, comprises a transport device 110 having a transport member 111 for transporting a recording medium W, an uncoiler 120 for unwinding a long, unprinted recording medium W wound in a roll shape, and a coiler 130 for winding up a printed recording medium W. An adhesive layer 11 is formed on the surface (adhesive layer forming surface) 111s of the transport member 111. The transport member 111 holds the recording medium W by adhering it to the adhesive layer 11. The printing apparatus 100 further comprises a printing unit 140 for printing a desired image pattern by applying ink to the recording medium W being transported by the transport member 111, an ink drying unit 150 for drying the ink on the recording medium W, and a cleaning unit 160 for cleaning the adhesive layer 11 after the recording medium W has separated.

[0013] The adhesive strength of the adhesive layer 11 tends to gradually decrease with repeated use or washing. Therefore, the printing apparatus 100 removes the old adhesive layer 11 that has been used multiple times and applies an aqueous adhesive 210 to the surface 111s of the transport member 111 to form a new adhesive layer 11. By using an aqueous adhesive 210, the workload on the user and the impact on the surrounding environment can be reduced compared to using an adhesive that uses an organic solvent.

[0014] As shown in Figure 2, the printing apparatus 100 further includes a coating liquid supply unit 170 that applies a coating liquid 12 of an aqueous adhesive 210 to the surface 111s of the transport member 111 and forms a coating film 13 by leveling the coating liquid 12 to a predetermined thickness, and a coating film drying unit 180 that dries (removes water from) the coating film 13 to form an adhesive layer 11. The recording medium W and each part of the printing apparatus 100 will be described in detail below.

[0015] For the sake of clarity, Figures 1 and 2 show the areas where the adhesive layer 11, coating liquid 12, and coating film 13 are provided using hatching. Also for the sake of clarity, the thicknesses of the adhesive layer 11 and coating film 13 are shown to be greater than the thickness of the transport member 111, but the relative sizes of these thicknesses are not limited to those shown. Furthermore, in Figure 2, the unwinding device 120, winding device 130, ink drying section 150, and cleaning section 160 are omitted from the illustration. In addition, in Figure 2, the tensioners 113 and 114, which will be described later, are located away from the transport member 111, but their illustration is omitted.

[0016] First, let's explain the recording medium W. A material to be printed can be used as the recording medium W. A material to be printed refers to fabrics, clothing, and other fashion products that are to be printed. Fabrics include woven, knitted, and nonwoven fabrics made from natural fibers such as cotton, silk, and wool, or synthetic fibers such as nylon, or composite fibers that are a mixture of these. Clothing and other fashion products include T-shirts, handkerchiefs, scarves, towels, tote bags, cloth bags, curtains, sheets, bed covers and other furniture after sewing, as well as fabrics before and after cutting that exist as parts before sewing.

[0017] The recording medium W is not limited to the above-mentioned printed material, but other materials such as plain paper, fine paper, and glossy paper, which are special papers for inkjet recording, can also be used. In addition, the recording medium W can also be, for example, a plastic film that has not been surface-treated for inkjet printing, i.e., one that does not have an ink-absorbing layer, a plastic coated on a substrate such as paper, or a plastic film to which a plastic film is bonded. The plastic is not particularly limited, but examples include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, and polypropylene.

[0018] Next, the transport device 110 of the printing device 100 will be described. As shown in Figure 1, the conveying device 110 includes a conveying member 111, a driving roller 112a and a driven roller 112b which are spaced apart from each other in the y-axis direction and extend along the x-axis direction, and roller-shaped tensioners 113 and 114 which apply tension to the recording medium W being conveyed by the conveying member 111.

[0019] In this embodiment, the conveying member 111 is a flexible endless belt. The conveying member 111 is stretched between the driving roller 112a and the driven roller 112b. In this embodiment, the surface 111s of the conveying member 111 on which the adhesive layer 11 is formed is the outer surface (circumferential surface) of the conveying member 111, which is an endless belt. However, an adhesive layer forming layer may be provided on the circumferential surface of the endless belt to improve adhesion with the adhesive layer 11. In this case, the conveying member 111 includes the endless belt and the adhesive layer forming layer, and the circumferential surface of the adhesive layer forming layer becomes the surface 111s on the conveying member 111 where the adhesive layer 11 is formed.

[0020] The materials used to construct the conveying member 111 are not particularly limited, but examples include various resin materials, various rubber materials, cloth, or resin materials or rubber materials with reinforcing members such as fiber materials embedded within them. The conveying member 111 may also be a so-called caterpillar-shaped structure, that is, a structure in which multiple unit pieces are rotatably connected and the whole structure is capable of bending and deforming.

[0021] The driving roller 112a rotates due to the operation of a motor (not shown). The driven roller 112b is positioned on the y-axis side of the driving roller 112a. The driven roller 112b receives the rotational force of the driving roller 112a via the conveying member 111 and rotates in conjunction with the driving roller 112a.

[0022] When printing onto the recording medium W, the driving roller 112a rotates counterclockwise in Figure 1 with an axis parallel to the x-axis as its central axis. Therefore, the transport member 111 rotates in a counterclockwise direction in Figure 1. Specifically, the portion of the transport member 111 located above the driving roller 112a and the driven roller 112b faces the y-axis direction -, and the portion of the transport member 111 located below the driving roller 112a and the driven roller 112b faces the y-axis direction +. The recording medium W unwound from the unwinding device 120 is held by the portion of the transport member 111 located above the driving roller 112a and the driven roller 112b. Therefore, the recording medium W is transported in the y-axis direction -.

[0023] Furthermore, when forming the adhesive layer 11, the main roller 112a rotates clockwise in Figure 2 with an axis parallel to the x-axis as its central axis. Therefore, the conveying member 111 rotates in a clockwise direction in Figure 2 together with the coating film 13.

[0024] As shown in Figure 1, tensioners 113 and 114 are spaced apart from each other in the y-axis direction and extend along the x-axis direction. Tensioners 113 and 114 are configured to move in the z-axis direction by a moving mechanism (not shown) so as to move closer to and further away from the transport member 111. Examples of the moving mechanism include those equipped with a drive source such as an air cylinder, an oil cylinder, or a solenoid.

[0025] When printing on the recording medium W, tensioner 113 holds the recording medium W together with the transport member 111 between itself and the main roller 112a, and tensioner 114 holds the recording medium W together with the transport member 111 between itself and the driven roller 112b. The recording medium W, with appropriate tension applied by tensioners 113 and 114, is held and transported by the transport member 111 while maintaining that tension. When forming the adhesive layer 11, tensioners 113 and 114 are positioned in a standby position, separated upward from the transport member 111.

[0026] Next, the unwinding device 120 will be described. As shown in Figure 1, the unwinding device 120 is positioned upstream of the conveying device 110 in the conveying direction of the recording medium W (y-axis + side). The unwinding device 120 includes an unwinding roller (feed-out reel) 121 that has the function of winding the unprinted recording medium W into a roll and feeding out the recording medium W, and a roller-shaped tensioner 123 that applies tension to the recording medium W between the unwinding roller 121 and the conveying device 110. The unwinding roller 121 is rotated by a motor (not shown) to unwind the unprinted recording medium W.

[0027] However, the configuration of the unwinding device 120 is not limited to the above, as long as it can unwind the recording medium W. For example, the unwinding device 120 does not need to be provided with a tensioner 123, and the number and arrangement of tensioners provided in the unwinding device 120 are not particularly limited.

[0028] Next, the winding device 130 will be described. The winding device 130 is positioned downstream of the conveying device 110 in the conveying direction of the recording medium W (towards the y-axis direction). The winding device 130 includes a winding roller 131 for winding the recording medium W into a roll shape, and roller-shaped tensioners 133, 134, and 135 that apply tension to the recording medium W between the winding roller 131 and the conveying device 110. The winding roller 131 is rotated by a motor (not shown) to wind up the recording medium W.

[0029] However, the configuration of the winding device 130 is not limited to the above, as long as it can wind up the recording medium W. For example, the winding device 130 does not need to be provided with tensioners 133, 134, and 135, and the number and arrangement of tensioners provided in the winding device 130 are not particularly limited.

[0030] Next, we will explain the printing unit 140. The printing unit 140 includes a carriage unit 142 having a plurality of inkjet heads 141 that eject ink toward the recording medium W, and an x-axis table (not shown) that supports the carriage unit 142 so as to be movable in the x-axis direction.

[0031] Each inkjet head 141 includes, for example, a head body with an internal flow channel filled with ink, and a group of nozzles having openings. The head body is provided with a piezoelectric element (piezoelectric body) corresponding to each nozzle, and ink is ejected as droplets from the nozzle corresponding to the piezoelectric element to which voltage is applied.

[0032] The ink contains a dye or pigment as a coloring agent in water as a solvent, and comes in four colors, such as cyan (C), magenta (M), yellow (Y), and black (K). Each color of ink is ejected independently from the inkjet head 141.

[0033] When ink is being ejected onto the recording medium W, the carriage unit 142 is positioned above the portion of the recording medium W that is held by the transport member 111. The unwinding device 120 intermittently feeds out the recording medium W while it is being held by the transport member 111. At this time, the printing unit 140 ejects ink from the nozzle group onto the held recording medium W while the carriage unit 142 reciprocates in the x-axis direction. This forms a desired image pattern on the recording medium W, and printing is performed. The image pattern may be multi-color or monochrome. When ink is not being ejected onto the recording medium W, the carriage unit 142 is in standby position, separated from the recording medium W (transport member 111) in the x-axis direction when viewed from the z-axis direction.

[0034] However, the configuration of the printing unit 140 is not limited to the above, as long as it can print on the recording medium W. For example, the inkjet head 141 may be a thermal type instead of a piezo type. Also, the printing unit 140 may not use an inkjet head 141, for example, a transfer type printing method.

[0035] Next, we will explain the ink drying section 150. As shown in Figure 1, the ink drying unit 150 is positioned downstream of the printing unit 140 in the transport direction of the recording medium W (y-axis direction - side) and upstream of the winding roller 131 in the transport direction of the recording medium W (y-axis direction + side). The ink drying unit 150 is composed of, for example, a heater that dries the ink on the recording medium W by heating, a blower that dries the ink by blowing air, or a combination of a heater and a blower. Note that the printing device 100 does not necessarily have to be provided with an ink drying unit 150.

[0036] Next, the cleaning unit 160 will be described. The cleaning unit 160 is located below the transport member 111 and the driven roller 112b. The cleaning unit 160 includes a storage tank 161 for storing cleaning fluid and a cleaning brush 162 located inside the storage tank 161. The cleaning brush 162 is configured to rotate by a motor (not shown). The cleaning unit 160 is also configured to move in the z-axis direction by a moving mechanism (not shown), allowing it to approach and move away from the transport member 111. Examples of moving mechanisms include those equipped with a drive source such as an air cylinder, an oil cylinder, or a solenoid.

[0037] When printing is being done on the recording medium W, the cleaning unit 160 is positioned so that the cleaning brush 162 contacts the adhesive layer 11 on the transport member 111. As the cleaning brush 162 rotates, cleaning liquid is applied to the surface of the adhesive layer 11 after the recording medium W has separated from it, and the adhesive layer 11 is brushed. This removes foreign matter such as ink composition and fibers from the recording medium W that have adhered to the adhesive layer 11. When the adhesive layer 11 is being formed, the cleaning unit 160 is positioned in a standby position away from the transport member 111 and the coating film 13.

[0038] However, the configuration of the cleaning unit 160 is not limited to the above, as long as the adhesive layer 11 can be cleaned when necessary. For example, the cleaning unit 160 may be configured to spray cleaning liquid from a nozzle toward the adhesive layer 11 by operating a pump, thereby cleaning the adhesive layer 11. Alternatively, the cleaning unit 160 may be configured to remove foreign matter by sliding a blade or brush against the adhesive layer 11. Furthermore, the printing device 100 does not necessarily have to be provided with a cleaning unit 160.

[0039] Next, the coating liquid supply unit 170 will be described. As shown in Figure 2, the coating liquid supply unit 170 includes a coating liquid supply source 170a that applies the coating liquid 12 of the aqueous adhesive 210 to the surface 111s of the transport member 111, and a blade 170b that levels the coating liquid 12 applied to the surface 111s of the transport member 111 by the coating liquid supply source 170a to a predetermined thickness and forms a coating film 13.

[0040] The coating liquid supply source 170a applies the coating liquid 12 of the aqueous adhesive 210 to the area of ​​the surface 111s of the conveying member 111 that is located above the driving roller 112a and the driven roller 112b. The coating liquid supply source 170a includes a storage section 171 for storing the aqueous adhesive 210, a liquid delivery pipe 172 for delivering the aqueous adhesive 210 from the storage section 171 to the vicinity of the surface 111s of the conveying member 111, and a liquid delivery pump 173 provided in the middle of the liquid delivery pipe 172.

[0041] The storage section 171 is composed of a rigid or flexible container capable of storing the aqueous adhesive 210. The upper end (one end) of the liquid delivery pipe 172 is connected to the container that constitutes the storage section 171. The lower end (the other end) of the liquid delivery pipe 172 is located above the transport member 111 and downstream in the transport direction of the recording medium W (y-axis direction) from below the carriage unit 142 of the printing section 140. When the liquid delivery pump 173 is operated, the aqueous adhesive 210 in the storage section 171 is delivered via the liquid delivery pipe 172 and discharged as a coating liquid 12 from the lower end of the liquid delivery pipe 172 toward the surface 111s of the transport member 111. The lower end of the liquid delivery pipe 172 branches into multiple channels, although this is not shown. The branched channels are aligned along the x-axis direction, that is, along the width direction of the transport member 111. This allows the coating liquid 12 to be supplied evenly (without excess or deficiency) and uniformly to the required area of ​​the surface 111s of the transport member 111.

[0042] The container constituting the storage section 171 is a separate container from the container body 220 (see Figure 3) of the aqueous adhesive container 200, which will be described later. When the amount of aqueous adhesive 210 in the storage section 171 decreases, the aqueous adhesive 210 may be replenished from the container body 220 into the container constituting the storage section 171. Furthermore, the storage section 171 is configured to allow the container body 220 to be detachably installed. When the aqueous adhesive 210 in the container body 220 installed in the storage section 171 has been almost completely used up, the old container body 220 may be removed and a new container body 220 of the aqueous adhesive container 200 may be installed in the storage section 171.

[0043] The configuration and method for applying the aqueous adhesive 210 to the surface 111s of the transport member 111 are not limited to those described above. For example, the storage section 171 may be a flexible container, and the coating liquid supply source 170a may have a pressurizing section that pressurizes the storage section 171 from the outside instead of a liquid delivery pump 173. In this case, the pressurizing section pressurizes the storage section 171 to push the aqueous adhesive 210 in the storage section 171 into the liquid delivery pipe 172. Then, the coating liquid 12 of the aqueous adhesive 210 is discharged from the lower end of the liquid delivery pipe 172 and applied to the surface 111s of the transport member 111. Examples of pressurizing sections include those that pressurize the storage section 171 with air pressure, and those that physically pressurize it using members such as pressurizing plates or pressurizing rollers.

[0044] Furthermore, the coating liquid supply source 170a may be configured to supply the aqueous adhesive 210 in the storage section 171 to the surface 111s of the transport member 111 by free fall via the liquid supply pipe 172. Alternatively, the printing device 100 may not have a coating liquid supply source 170a, and the aqueous adhesive 210 may be applied to the surface 111s of the transport member 111 by, for example, an external coating liquid supply source. Moreover, the coating liquid supply source 170a itself may not exist, regardless of whether it is included in the printing device 100 or not. In this case, the aqueous adhesive 210 can be applied to the surface 111s of the transport member 111 by a worker using an applicator or the like.

[0045] Next, I will explain blade 170b. The blade 170b is elongated and extends in the width direction of the conveying member 111. The blade 170b may be made of a rigid material or be flexible.

[0046] When leveling the coating liquid 12 to form the coating film 13, the blade 170b is positioned upstream of the lower end of the liquid delivery pipe 172 in the direction of transport of the recording medium W (y-axis direction + side), and downstream of the lower part of the carriage unit 142 of the printing unit 140 in the direction of transport of the recording medium W (y-axis direction - side). The lower end of the blade 170b (the z-axis direction - end) is spaced a predetermined distance from the surface 111s. Preferably, the distance between the lower end of the blade 170b and the surface 111s is approximately equal along the longitudinal direction of the blade 170b, i.e., along the x-axis direction. This makes it possible to make the thickness of the coating film 13 uniform in the x-axis direction.

[0047] When the coating liquid 12 is not leveled, the blade 170b is moved to a retracted position above the transport member 111 by a moving mechanism (not shown). Examples of such moving mechanisms include those equipped with a drive source such as an air cylinder, oil cylinder, or solenoid. If the printing device 100 is not equipped with a moving mechanism for the blade 170b and the coating liquid 12 is not leveled, the operator may remove the blade 170b from the transport device 110.

[0048] The configuration and method for leveling the aqueous adhesive 210 (coating liquid 12) applied to the surface 111s of the conveying member 111 (forming a coating film 13) are not limited to those described above. For example, the printing apparatus 100 may be equipped with other leveling tools such as a squeegee, roller, brush, or air knife instead of the blade 170b. Alternatively, the printing apparatus 100 may not be equipped with leveling tools such as the blade 170b, and an operator may level the coating liquid 12 applied to the surface 111s of the conveying member 111 using tools such as a squeegee, roller, or brush.

[0049] Next, the coating drying section 180 will be described. The coating drying section 180 is located below the transport member 111. The coating drying section 180 is composed of, for example, a heater for drying the coating 13 by heating, a blower for drying the coating 13 by blowing air, or a combination of a heater and a blower. However, the printing device 100 may be made without a coating drying section 180, and the coating 13 may be allowed to air dry naturally.

[0050] The printing apparatus 100 also includes a control unit (not shown). The control unit is electrically connected to the transport device 110, unwinding device 120, winding device 130, printing unit 140, ink drying unit 150, cleaning unit 160, coating liquid supply unit 170, and coating film drying unit 180, and controls their operation. The control unit is composed of, for example, a processor such as a CPU (Central Processing Unit), memory such as RAM (Random Access Memory) and ROM (Read Only Memory), and an interface for sending and receiving signals to and from each part of the printing apparatus 100.

[0051] Next, the aqueous adhesive 210 that constitutes the coating solution 12 will be described. The aqueous adhesive 210 is an aqueous adhesive composition containing water and adhesive particles. More specifically, the aqueous adhesive 210 is an emulsion in which adhesive particles are dispersed in water. The constituent materials and physical properties of the aqueous adhesive 210 are described in detail below.

[0052] [Adhesive particles] The resin constituting the adhesive particles is not particularly limited, but for example, a (meth)acrylic resin can be used. By including a (meth)acrylic resin, the adhesive strength and durability of the adhesive layer 11 can be improved.

[0053] The (meth)acrylic resin is not particularly limited as long as it is a polymer obtained by polymerizing a (meth)acrylic monomer such as (meth)acrylic acid or (meth)acrylic acid ester as one component. Examples of (meth)acrylic resins include homopolymers formed by polymerizing a single type of (meth)acrylic monomer, copolymers formed by polymerizing multiple types of (meth)acrylic monomers, and copolymers formed by polymerizing a (meth)acrylic monomer with other monomers. The (meth)acrylic monomer is not particularly limited, but examples include (meth)acrylic monomers having aliphatic groups with 3 or fewer carbon atoms, such as methyl methacrylate (MMA), ethyl methacrylate (EMA), and n-propyl methacrylate (PMA); (meth)acrylic monomers having aliphatic groups with 4 or more carbon atoms, such as butyl methacrylate (BMA), butyl acrylate (BA), and 2-ethylhexyl acrylate (2EHA); and (meth)acrylic monomers having aromatic groups, such as styrene (St). Other monomers include, but are not limited to, acrylamide and acrylonitrile.

[0054] The combination of (meth)acrylic monomers constituting the (meth)acrylic resin is not particularly limited, but examples include those containing ethyl methacrylate, butyl acrylate, and 2-ethylhexyl acrylate.

[0055] The aqueous adhesive composition contains at least a first (meth)acrylic resin and a second (meth)acrylic resin as the (meth)acrylic resin, and it is preferable that the glass transition temperature Tg1 of the first (meth)acrylic resin is higher than the glass transition temperature Tg2 of the second (meth)acrylic resin. By including two (meth)acrylic resins having such different glass transition temperatures Tg, the adhesive strength, durability, and the effect of suppressing the decrease in adhesive strength during brushing tend to be further improved.

[0056] The glass transition temperature Tg1 of the first (meth)acrylic resin is not particularly limited, but is preferably between -25°C and 25°C, and more preferably between -20°C and 20°C. When the glass transition temperature Tg1 is within the above range, the adhesive strength tends to improve.

[0057] The glass transition temperature Tg2 of the second (meth)acrylic resin is not particularly limited, but is preferably between -70°C and -15°C, and more preferably between -65°C and -20°C. When the glass transition temperature Tg2 is within the above range, the decrease in adhesive strength during brushing tends to be further suppressed.

[0058] The difference between the glass transition temperature Tg1 and the glass transition temperature Tg2, |Tg1-Tg2|, is preferably between 10°C and 50°C, and more preferably between 15°C and 45°C. When the difference |Tg1-Tg2| is within the above range, the adhesive strength and the effect of suppressing the decrease in adhesive strength during brushing tend to be further improved.

[0059] The glass transition temperature can be adjusted by the homopolymer glass transition temperature of the polymerizable compound used and the mass ratio of the polymerizable compound used. The glass transition temperature can be measured by conventionally known methods.

[0060] The monomers contained in the first (meth)acrylic resin are not particularly limited, but it is preferable that they contain at least ethyl methacrylate, butyl methacrylate, butyl acrylate, and 2-ethylhexyl acrylate; at least ethyl methacrylate, styrene, butyl acrylate, and 2-ethylhexyl acrylate; at least methyl methacrylate, butyl acrylate, and 2-ethylhexyl acrylate; or at least butyl methacrylate, butyl acrylate, and 2-ethylhexyl acrylate. By using the first (meth)acrylic resin containing the above monomers, the adhesive strength and the effect of suppressing the decrease in adhesive strength during brushing tend to be further improved.

[0061] The first (meth)acrylic resin described above preferably contains a (meth)acrylic monomer as a constituent unit, the homopolymer having a glass transition temperature of 40°C or higher. The inclusion of the above monomer in the first (meth)acrylic resin tends to further improve the adhesive strength of the adhesive layer 11 and the effect of suppressing the decrease in adhesive strength during brushing.

[0062] The content of (meth)acrylic monomers having a homopolymer glass transition temperature of 40°C or higher is preferably 20% by mass or more and 70% by mass or less, and more preferably 25% by mass or more and 65% by mass or less, relative to the total amount of the first (meth)acrylic resin. When the content of (meth)acrylic monomers having a homopolymer glass transition temperature of 40°C or higher is within the above range, the adhesive strength of the adhesive layer 11 and the effect of suppressing the decrease in adhesive strength during brushing tend to be further improved.

[0063] The monomers contained in the second (meth)acrylic resin are not particularly limited, but it is preferable that they contain at least ethyl methacrylate, butyl methacrylate, butyl acrylate, and 2-ethylhexyl acrylate, or at least n-propyl methacrylate, butyl methacrylate, butyl acrylate, and 2-ethylhexyl acrylate. Using the second (meth)acrylic resin containing the above monomers tends to further improve adhesive strength and the effect of suppressing the decrease in adhesive strength during brushing.

[0064] The content of the first (meth)acrylic resin is preferably 50% by mass or more and 85% by mass or less, and more preferably 53% by mass or more and 82% by mass or less, relative to the total amount of the first (meth)acrylic resin and the second (meth)acrylic resin. When the content of the first (meth)acrylic resin is within the above range, the adhesive strength of the adhesive layer 11 and the effect of suppressing the decrease in adhesive strength during brushing tend to be further improved.

[0065] The content of the second (meth)acrylic resin is preferably less than 50% by mass, and more preferably 10% by mass or more and 48% by mass or less, relative to the total amount of the first (meth)acrylic resin and the second (meth)acrylic resin. When the content of the second (meth)acrylic resin is within the above range, the adhesive strength of the adhesive layer 11 and the effect of suppressing the decrease in adhesive strength during brushing tend to be further improved.

[0066] The aqueous adhesive 210 (coating solution 12) may contain, in addition to adhesive particles, various additives such as tackifying surfactants, surfactants, colorants (dyes, pigments), thickeners, preservatives, fungicides, and other additives, as described later. The solid content in the aqueous adhesive 210 is mainly adhesive particles, but if the aqueous adhesive 210 contains water-insoluble additives (e.g., pigments), these also constitute solid content, although in trace amounts compared to the adhesive particles. Therefore, hereafter, when referring to the "solid content of the aqueous adhesive 210," it refers to the amount of adhesive particles in the aqueous adhesive 210.

[0067] The solid content in the aqueous adhesive 210 (coating liquid 12), i.e., the content of adhesive particles, and especially the total content of (meth)acrylic resin, is not particularly limited, but is preferably 20% by mass or more and 60% by mass or less, and more preferably 30% by mass or more and 60% by mass or less, relative to the total amount of the aqueous adhesive composition (coating liquid 12). By setting the solid content of the aqueous adhesive 210 to above the lower limit, the adhesive strength and durability of the adhesive layer 11 formed using this aqueous adhesive 210 tend to be further improved. Furthermore, by setting the solid content of the aqueous adhesive 210 to below the upper limit, the concentration of adhesive particles in the aqueous adhesive 210 can be made appropriate, and the state in which the adhesive particles are uniformly dispersed in water in the aqueous adhesive 210 can be well maintained. As a result, the generation of aggregates, which are formed when adhesive particles aggregate and form clumps as described later, can be suppressed.

[0068] The content of the first (meth)acrylic resin is preferably 10% by mass or more and 60% by mass or less, and more preferably 20% by mass or more and 60% by mass or less, based on the total amount of the aqueous adhesive composition (coating liquid 12). When the content of the first (meth)acrylic resin is within the above range, the adhesive strength of the adhesive layer 11 and the effect of suppressing the decrease in adhesive strength during brushing tend to be further improved.

[0069] The content of the second (meth)acrylic resin is preferably 50% by mass or less, and more preferably 1% by mass or more and 40% by mass or less, relative to the total amount of the aqueous adhesive composition (coating liquid 12). When the content of the second (meth)acrylic resin is within the above range, the adhesive strength of the adhesive layer 11 and the effect of suppressing the decrease in adhesive strength during brushing tend to be further improved.

[0070] The aqueous adhesive composition may contain resins other than (meth)acrylic resins. Such other resins are not particularly limited, but examples include urethane resins, silicone resins, and various elastomers (rubber-based materials). Furthermore, the resin is not limited to the above-mentioned (meth)acrylic resin or a composition primarily composed of (meth)acrylic resins; other examples include urethane resins, silicone resins, and various rubber-based materials.

[0071] [Tackifier] The aqueous adhesive composition preferably contains no or only a small amount of tackifier. When no or only a small amount of tackifier is present, the adhesive strength of the adhesive layer 11 and the effect of suppressing the decrease in adhesive strength during brushing tend to be more sustained. Typical examples of such tackifiers include rosin compounds, terpene compounds, and hydrocarbon resins. More specifically, examples include rosin compounds such as natural rosin, modified rosin, glycerol ester of natural rosin, glycerol ester of modified rosin, pentaerythritol ester of natural rosin, and pentaerythritol ester of modified rosin; terpene compounds such as copolymers of natural terpenes, three-dimensional polymers of natural terpenes, aromatically modified terpene resins, hydrogenated derivatives of aromatically modified terpene resins, terpene phenol resins, and terpene resins (monoterpenes, diterpenes, triterpenes, polypertenes, etc.); and hydrocarbon resins such as aliphatic petroleum hydrocarbon resins (C5 resins), hydrogenated derivatives of aliphatic petroleum hydrocarbon resins, styrene oligomers, aromatic petroleum hydrocarbon resins (C9 resins), and hydrogenated derivatives of aromatic petroleum hydrocarbon resins.

[0072] It is preferable that the tackifier is either not included or is included in small amounts. If a tackifier is included, its content is not particularly limited, but is preferably 5% by mass or less, more preferably 4% by mass or less, and even more preferably 0.1% by mass or more and 3.8% by mass or less, relative to the total amount of the aqueous adhesive composition (coating liquid 12). When the tackifier content is within the above range, the adhesive strength of the resulting adhesive layer 11 and the effect of suppressing the decrease in adhesive strength during brushing tend to be sustained. From a similar viewpoint, it is preferable that the total content of compounds selected from the group consisting of rosin compounds, terpene compounds, and hydrocarbon resins is also within the same range as above.

[0073] [water] The water content in the aqueous adhesive composition (coating liquid 12) is not particularly limited, but is preferably 30% by mass or more and 80% by mass or less, more preferably 35% by mass or more and 70% by mass or less, and even more preferably 40% by mass or more and 60% by mass or less. This makes it easier to spread the coating liquid 12 applied to the surface 111s to a uniform thickness.

[0074] [Surfactants] The aqueous adhesive composition may contain a surfactant. The surfactant is not particularly limited, but examples include anionic surfactants, nonionic surfactants, and cationic surfactants.

[0075] Examples of anionic surfactants include alkyl sulfocarboxylates, alkyl diphenyl ether disulfonates, α-olefin sulfonates, polyoxyethylene alkyl ether acetates, N-acyl amino acids and their salts, N-acyl methyl taurates, alkyl sulfates such as ammonium lauryl sulfate and sodium lauryl sulfate, alkyl sulfate polyoxyalkyl ether sulfates, alkyl sulfate polyoxyethylene alkyl ether phosphates, rosinic acid soaps, castor oil sulfates, lauryl alcohol sulfates, alkylphenol type phosphates, alkyl type phosphates, alkylaryl sulfonates, diethyl sulfosaturates, diethylhexyl sulfosaturates, and dioctyl sulfosaturates.

[0076] Examples of nonionic surfactants include acetylene glycol surfactants, silicone surfactants, polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene hydrogenated castor oil, propylene glycol fatty acid esters, glycerin fatty acid esters, polyglycerin fatty acid esters, sorbitan fatty acid esters, sucrose fatty acid esters, alkyl polyglycosides, alkyldiethanolamides, and alkylamine oxides. Examples of commercially available nonionic surfactants are not particularly limited, but include Emulgen 123P, 430, 1108 (product names of Kao Corporation), Newcol 1006, 1008, 1020 (product names of Nippon Emulsifier Co., Ltd.), and Neugen DL-0415, ET-116B, ET-106A, DH-0300, YX-400, EA-160 (product names of Daiichi Kogyo Seiyaku Co., Ltd.).

[0077] Cationic surfactants include alkylamine salts, fatty acid amidoamine salts, monoalkyl quaternary ammonium salts, dialkyl quaternary ammonium salts, trialkyl quaternary ammonium salts, benzalkonium quaternary ammonium salts, benzethonium chloride, and alkylpyridinium salts.

[0078] In this embodiment, nonionic surfactants are preferred among these, and more specifically, alkyl ether-based nonionic surfactants are preferred. Using such surfactants tends to maintain durability.

[0079] The surfactant content is preferably 1% by mass or more and 7% by mass or less, and more preferably 2% by mass or more and 6% by mass or less, based on the total amount of the aqueous adhesive composition (coating liquid 12).

[0080] [organic solvent] In this embodiment, the aqueous adhesive composition preferably contains no organic solvent or only a small amount of it, from the viewpoint of reducing environmental impact and impact on the human body. Furthermore, if an organic solvent is included, the content of the organic solvent is preferably 5.0% by mass or less, and more preferably 2.5% by mass or less, relative to the total amount of the aqueous adhesive composition (coating liquid 12). This reduces the environmental impact and the amount of VOCs (volatile organic compounds) when using the aqueous adhesive composition, which tends to improve the working environment.

[0081] [Colorants] In this embodiment, the aqueous adhesive composition preferably contains no colorants such as dyes and pigments, or contains only a small amount. If it does contain colorants, the amount of colorants is preferably 1.0% by mass or less, and more preferably 0.5% by mass or less, relative to the total amount of the aqueous adhesive composition (coating liquid 12). This clearly distinguishes the aqueous adhesive composition of this embodiment from compositions intended for coloring, such as ink compositions, printing pastes, and paints.

[0082] [Storage modulus] The storage modulus of the adhesive layer 11 obtained in this embodiment at 23°C is 1.5 × 10⁻⁶ 5 Pa or more 5.0×10 5 It is preferable that it is less than or equal to Pa, and 1.6 × 10 5 Pa or more 4.8×10 5 It is more preferable to be less than or equal to Pa, 2.0 × 10 5 Pa or more 4.5×10 5 It is even more preferable that the storage modulus is less than or equal to Pa. 5 Having a storage modulus of Pa or higher suppresses the reduction in adhesive strength due to water washing of the adhesive surface. Furthermore, the above storage modulus is 5.0 × 10⁻⁶. 5 By having a Pa value below a certain level, the initial adhesive strength can be increased.

[0083] The method for forming the adhesive layer 11 for measuring the storage elastic modulus is not particularly limited. For example, an aqueous adhesive composition is applied to a 25-mm-wide slide glass at room temperature to a thickness of 0.2 mm and dried under conditions of 50% humidity, 23 °C, and for 12 hours to obtain it.

[0084] When the adhesive layer 11 consisting only of the first (meth)acrylic resin (hereinafter referred to as the "first acrylic adhesive layer") is formed by the same method as the aqueous adhesive composition, the storage elastic modulus of the first acrylic adhesive layer at 23 °C is not particularly limited, but is preferably 1.0×10 5 Pa or more and 8.0×10 5 Pa or less, and more preferably 1.6×10 5 Pa or more and 7.6×10 5 Pa or less. When the storage elastic modulus of the first acrylic adhesive layer is within the above range, the adhesive force of the adhesive layer 11 and the effect of suppressing the decrease in adhesive force during brushing tend to be further improved.

[0085] When the adhesive layer 11 consisting only of the second (meth)acrylic resin (hereinafter referred to as the "second acrylic adhesive layer") is formed by the same method as the aqueous adhesive composition, the storage elastic modulus of the second acrylic adhesive layer at 23 °C is not particularly limited, but is preferably 6.0×10 5 or more and 8.0×10 5 Pa or less, and more preferably 7.0×10 5 or more and 7.5×10 5 Pa or less. When the storage elastic modulus of the second acrylic adhesive layer is within the above range, the adhesive force of the adhesive layer 11 and the effect of suppressing the decrease in adhesive force during brushing tend to be further improved.

[0086] [Adhesive force] The adhesive strength of the adhesive layer 11 obtained by this embodiment at room temperature (23°C) is not particularly limited, but is preferably 0.3 N / 50 mm or more and 2.0 N / 50 mm or less, more preferably 0.5 N / 50 mm or more and 2.0 N / 50 mm or less, and even more preferably 1.0 N / 50 mm or more and 2.0 N / 50 mm or less. By having the adhesive strength at 23°C within the above range, the adhesive strength of the adhesive layer 11 and the effect of suppressing the decrease in adhesive strength during brushing are further improved. The method for measuring the adhesive strength will be described later.

[0087] [Particle size] The average particle size of the adhesive particles in the aqueous adhesive 210 (coating liquid 12) is preferably 50 nm to 300 nm, more preferably 100 nm to 300 nm, and even more preferably 200 nm to 250 nm. By setting the average particle size of the adhesive particles within the above range, the adhesive particles can be sufficiently dispersed in the aqueous adhesive 210, and this good dispersion state of the adhesive particles can be maintained even in the coating film 13 leveled to a predetermined thickness. As a result, a uniform adhesive layer 11 can be formed, and the adhesive strength and durability of the adhesive layer 11 can be made excellent. When the recording medium W adheres to such an adhesive layer 11, the transport member 111 can transport the recording medium W stably and appropriately. As a result, the printing apparatus 100 can prevent printing defects such as misalignment caused by poor holding or poor transport of the recording medium W, and can print an appropriate and high-quality image on the recording medium W. The particle size of the adhesive particles is not particularly limited, but can be measured, for example, by laser diffraction / scattering (LD) or dynamic image analysis (DIA).

[0088] [viscosity] The viscosity of the aqueous adhesive 210 (coating liquid 12) at 25°C is not particularly limited, but is preferably 2 mPa·s to 15 mPa·s, more preferably 2 mPa·s to 10 mPa·s, and even more preferably 2 mPa·s to 7 mPa·s. By setting the viscosity of the aqueous adhesive 210 within the above range, it is possible to easily spread the aqueous adhesive 210 (coating liquid 12) on the transport member 111 to a uniform thickness, contributing to the uniformity of the thickness of the adhesive layer 11 and the homogenization of the surface properties. The viscosity of the aqueous adhesive 210 is not particularly limited, but can be measured, for example, by a B-type viscometer. The viscosity of the aqueous adhesive 210 (coating liquid 12) can be adjusted mainly by the composition of the solids, molecular weight, etc., and their content, but it can also be adjusted by adding a thickening agent as an additive to the aqueous adhesive 210.

[0089] [thickness] The average thickness of the adhesive layer 11 formed on the transport member 111 is not particularly limited, but is preferably 0.03 mm to 7.0 mm, more preferably 0.08 mm to 1.0 mm, and even more preferably 0.1 mm to 0.5 mm. By setting the average thickness of the adhesive layer 11 within the above range, the adhesive strength of the adhesive layer 11 can be improved and its durability can be increased. Furthermore, when forming the adhesive layer 11 using the coating liquid 12, a uniform and homogeneous adhesive layer 11 with good adhesion to the surface 111s can be formed relatively easily.

[0090] Next, the aqueous adhesive container 200 will be described. As shown in Figure 3, the aqueous adhesive container 200 comprises the aforementioned aqueous adhesive 210 and a container 240 for containing the aqueous adhesive 210. The container 240 contains the aqueous adhesive 210 and has a container body 220 made of a flexible sheet material with an opening 235 formed therein, and a lid member 230 that is attached to the opening 235 so as to be openable and closable.

[0091] The aqueous adhesive container 200 is used to store the aqueous adhesive 210 to be applied to the surface 111s of the transport member 111 of the printing device 100. Specifically, for example, the user can store the aqueous adhesive container 200, and when the volume of aqueous adhesive 210 in the container constituting the storage section 171 decreases due to the formation of an adhesive layer 11 on the surface 111s of the transport member 111 in the printing device 100, the user can transfer (replenish) the aqueous adhesive 210 from the aqueous adhesive container 200 to the container constituting the storage section 171.

[0092] Furthermore, as mentioned above, the storage section 171 may be configured to allow the container body 220 of the aqueous adhesive container 200 to be detachably installed. Specifically, an unopened aqueous adhesive container 200 is placed in the storage section 171, the aqueous adhesive container 200 is opened, and the upper end of the liquid supply pipe 172 is connected to the opening 235, as shown in Figure 2. This allows the aqueous adhesive 210 in the container body 220 to be applied to the surface 111s of the transport member 111 via the liquid supply pipe 172 connected to the opening 235. When the aqueous adhesive 210 in the container body 220 is almost used up, it can be replaced with a new aqueous adhesive container 200, and the application of aqueous adhesive 210 to the transport member 111 can be continued. The uses of the aqueous adhesive container 200 are not limited to these, but in the following description, it is typically used when transferring aqueous adhesive 210 from the stored aqueous adhesive container 200 to the container constituting the storage section 171.

[0093] Figure 4 is a cross-sectional view taken along the line IV-IV in Figure 3. Figure 5 is an exploded perspective view showing the state before the ends of the pair of side sheets 231, 232 and bottom sheet 233 that make up the container body 220 of the aqueous adhesive container 200 shown in Figure 3 are joined together.

[0094] In this embodiment, the container body 220 includes a pair of opposing side sheets 231, 232 and a bottom sheet 233, as shown in Figures 4 and 5.

[0095] The sheet material (hereinafter also simply referred to as "sheet material") constituting the pair of side sheets 231, 232 and bottom sheet 233 is not particularly limited, but is composed of, for example, a resin sheet consisting of a single resin layer, a resin sheet consisting of multiple resin layers, or a resin sheet having a single or multiple resin layer and a metal layer laminated to the resin layer by, for example, vapor deposition, bonding, or lamination.

[0096] The resin used in the resin sheet is not particularly limited, but examples include polyethylene, polypropylene, polyolefins such as ethylene vinyl alcohol copolymer, various polyamides (nylon™ registered trademark), polyesters such as polyethylene terephthalate and polybutylene terephthalate, polystyrene, and polyvinyl chloride. Among these, particularly preferred materials include polypropylene (PP), stretched polypropylene (OPP), unstretched polypropylene (CPP), ethylene vinyl alcohol copolymer resin (EVOH), stretched nylon (ONY), unstretched nylon (CNY), polyethylene terephthalate (PET), and polystyrene (PS). The metal used in the metal layer is not particularly limited, but examples include aluminum or aluminum alloys, stainless steel, copper or copper alloys. The sheet materials constituting the pair of side sheets 231, 232 and the bottom sheet 233 may be of the same composition or different compositions.

[0097] Resin sheets consisting of multiple resin layers or resin sheets with a metal layer have the advantage of being able to achieve sufficient strength and high gas barrier properties (impermeability to water vapor and oxygen) despite being relatively thin sheet materials, i.e., sheet materials that are sufficiently flexible, compared to resin sheets consisting of a single resin layer.

[0098] Hereinafter, the state before joining the ends of the pair of side sheets 231, 232 and the bottom sheet 233 to form a bag will simply be referred to as "before joining". As shown in Figure 5, the shape of each side sheet 231, 232 before joining is a rectangle with the z-axis direction as the longitudinal direction and the y-axis direction as the transverse direction. The pair of side sheets 231, 232 are arranged to face each other in the x-axis direction. In Figure 5, side sheet 232 is positioned on the positive x-axis side of side sheet 231.

[0099] The bottom sheet 233 before joining is a rectangular sheet with the y-axis as its longitudinal direction, folded in half so that it is convex upwards (towards the z-axis + side) when viewed from the y-axis direction, i.e., it is mountain-folded. Therefore, a fold line 233f extending along the y-axis direction is formed approximately in the center of the bottom sheet 233 in the x-axis direction. The folded bottom sheet 233 is placed between the lower parts of the pair of side sheets 231 and 232.

[0100] Of the outer periphery of the side sheet 231, the short side portion located below the center of the side sheet 231 and extending along the y-axis is called the "lower end portion 231a," and the short side portion located above the center of the side sheet 231 and extending along the y-axis is called the "upper end portion 231b." Of the outer periphery of the side sheet 231, the long side portion located on the y-axis-side of the center of the side sheet 231 and extending along the z-axis is called the "y-axis-side end portion 231c," and the long side portion located on the y-axis-side of the center of the side sheet 231 and extending along the z-axis is called the "y-axis-side end portion 231d."

[0101] Similarly, of the outer periphery of the side sheet 232, the short side portion located below the center of the side sheet 232 and extending along the y-axis is called the "lower end portion 232a," and the short side portion located above the center of the side sheet 232 and extending along the y-axis is called the "upper end portion 232b." Of the outer periphery of the side sheet 232, the long side portion located on the y-axis-side of the center of the side sheet 232 and extending along the z-axis is called the "y-axis-side end portion 232c," and the long side portion located on the y-axis-side of the center of the side sheet 232 and extending along the z-axis is called the "y-axis-side end portion 232d."

[0102] Of the outer periphery of the bottom sheet 233, the long side portion that faces the lower end portion 231a of the side sheet 231 and extends along the y-axis direction is called the "lower end portion 233a on the x-axis direction side", and the long side portion that faces the lower end portion 232a of the side sheet 232 and extends along the y-axis direction is called the "lower end portion 233b on the x-axis direction side". Of the outer periphery of the bottom sheet 233, the folded short side portion that is located on the y-axis direction side of the center of the bottom sheet 233 in the y-axis direction is called the "y-axis direction side end portion 233c", and the folded short side portion that is located on the y-axis direction side of the center of the bottom sheet 233 in the y-axis direction is called the "y-axis direction side end portion 233d".

[0103] As shown in Figures 4 and 5, the lower end 231a of the side sheet 231 and the lower end 233a on the x-axis side of the bottom sheet 233 are joined to each other in an overlapping state. The lower end 232a of the side sheet 232 and the lower end 233b on the x-axis side of the bottom sheet 233 are joined to each other in an overlapping state. The method of joining the ends of the sheet materials is not particularly limited and depends on the constituent materials of the sheet materials, but examples include heat fusion, high-frequency fusion, ultrasonic fusion, and adhesive bonding.

[0104] As shown in Figures 3 and 5, the lower part of the y-axis-side end 231c of the side sheet 231, the y-axis-side end 233c of the bottom sheet 233, and the lower part of the y-axis-side end 232c of the side sheet 232 are joined to each other in an overlapping manner. The remaining portion of the y-axis-side end 231c of the side sheet 231 and the remaining portion of the y-axis-side end 232c of the side sheet 232 are joined to each other in an overlapping manner.

[0105] Furthermore, the lower part of the y-axis positive end 231d of the side sheet 231, the y-axis positive end 233d of the bottom sheet 233, and the lower part of the y-axis positive end 232d of the side sheet 232 are joined to each other in an overlapping state. The remaining portion of the y-axis positive end 231d of the side sheet 231 and the remaining portion of the y-axis positive end 232d of the side sheet 232 are joined to each other in an overlapping state.

[0106] As shown in Figure 4, the mouth portion 235 in this embodiment is composed of a cylindrical body. In this embodiment, the mouth portion 235 is a rigid body. The material of the mouth portion 235 is not particularly limited, but various resin materials, various metal materials, etc. can be used.

[0107] A male screw portion is formed on the outer peripheral surface of the upper part of the opening 235. As shown in Figures 3 and 4, the lower end of the opening 235 is positioned between the central part in the y-axis direction of the upper end 231b of the side sheet 231 and the central part in the y-axis direction of the upper end 232b of the side sheet 232, and is joined to them. In addition, the remaining parts of the upper end 231b of the side sheet 231 and the remaining parts of the upper end 232b of the side sheet 232 are joined to each other in an overlapping state.

[0108] As a result, a bag-shaped container body 220 having an opening 235 is formed, as shown in Figure 4. The container body 220 is self-supporting because it has a bottom surface made of a bottom sheet 233. Specifically, as shown in Figure 3, the central part of the bottom sheet 233 in the y-axis direction is pushed down by the weight of the aqueous adhesive 210 inside the container body 220. Therefore, the bottom sheet 233 maintains a folded state at both ends in the y-axis direction, while the folded part becomes gentler in the center. That is, in the center, as shown in Figure 4, the lower end 233a on the x-axis direction - side and the lower end 233b on the x-axis direction + side are separated from each other. Therefore, the user can easily open and close the opening 235 with the lid member 230 while the container body 220 is self-supporting.

[0109] The internal space of the container body 220 includes an internal space S1 surrounded by a pair of side sheets 231, 232 and a bottom sheet 233 (sheet material), and an internal space S2 of the cylindrical mouth 235. Since the sheet material is flexible, the volume of the internal space S1 may change due to the deformation of the sheet material. In this embodiment, the mouth 235 is a rigid body, and the volume of the internal space S2 does not change significantly.

[0110] In this embodiment, the lid member 230 is composed of a cap with a female threaded portion formed on its inner circumferential surface. The female threaded portion of the lid member 230 can be screwed onto the male threaded portion of the opening 235. Hereinafter, the state in which the lid member 230 is screwed onto the opening 235 and the opening 235 is closed will also be simply referred to as the "closed state," and the state in which the lid member 230 is released from the opening 235 and the opening 235 is open, that is, the state in which the lid member 230 is removed from the opening 235, will also simply be referred to as the "open state."

[0111] When closed, it is preferable to prevent leakage of the aqueous adhesive 210 from the container 240 through the gap between the lid member 230 and the opening 235, and to prevent gases such as air from entering the container 240. In other words, it is preferable that the container 240 is liquid-tight and highly airtight when closed. From this viewpoint, a sealing material such as an O-ring or rubber sheet (not shown) may be placed between the lid member 230 and the opening 235.

[0112] However, the configuration of the container 240 is not limited to the above. For example, the sheet material may consist of one, two, or four or more sheets, and the shape of the sheet material and the position of the joints between the ends of the sheet material are not particularly limited. Also, the container body 220 is not limited to being made by joining sheet materials, but may also be made by integral molding such as blow molding, inflation molding, injection molding, extrusion molding, or multi-color molding. Furthermore, the configuration of the lid member 230 and the mouth 235 is not particularly limited as long as the mouth 230 can be opened and closed. For example, the mouth 235 may not have a male screw portion and the lid member 230 may not have a female screw portion, and the lid member 230 may be made of a cap made of an elastic material, and the lid member 230 may be attached to the mouth 235 so that the inner circumferential surface of the lid member 230 is in close contact with the outer circumferential surface of the upper end of the mouth 235. Also, the lid member 230 may be configured to fit into the mouth 235.

[0113] Furthermore, the installation position of the opening 235 on the container body 220 is not particularly limited; for example, the opening 235 may be formed to protrude from the side of the container body 220. The direction in which the opening 235 protrudes from the container body 220 may be any direction, such as in the x-axis direction, the y-axis direction, or a direction inclined at a predetermined angle with respect to the z-axis. In addition, the container body 220 may have multiple openings 235 of the same or different shapes.

[0114] The state after the empty container 240 has been manufactured and the water-based adhesive 210 has been placed inside, and the opening 235 has been closed by the lid member 230, and before the water-based adhesive 210 inside has been removed from the container 240, i.e., the state in which the container 240 is unopened, is defined as the "initial state". The state in which a portion of the water-based adhesive 210 inside the container 240 has been removed from the initial state is defined as the "usage state".

[0115] Furthermore, when the surrounding environment of container 240 is 25°C and 1 atm, the maximum volume of container 240 is defined as V0. Here, "maximum volume V0" corresponds to the volume of aqueous adhesive 210 when the entire internal space of container 240, which has been expanded to its maximum extent (i.e., the internal space S1 and internal space S2, which have been expanded to their maximum extent), is filled with aqueous adhesive 210. Also, regardless of whether it is in its initial state (unopened) or in a used state (opened), when the surrounding environment of container 240 is 25°C and 1 atm, the volume of aqueous adhesive 210 contained in container 240 is defined as V1, and the volume of gas present in container 240 is defined as V2.

[0116] In this embodiment, in the initial state, as shown in Figure 4, the aqueous adhesive 210 is present in the portion of the sheet material's internal space S1 excluding the upper part, and gas is present in the upper part of the sheet material's internal space S1 and in the internal space S2 of the opening 235. In this embodiment, the gas present in the container 240 is air. However, when the aqueous adhesive 210 is placed in the container 240, a gas other than air may be injected into the container 240.

[0117] Furthermore, in this embodiment, in the initial state, the container body 220 is in a state where the internal space S1 is expanded to its maximum extent by the internal aqueous adhesive 210 and gas, and V1 + V2 = V0. However, in the initial state V1 + V2 <V0であってもよい。

[0118] Furthermore, in this embodiment, in the initial state, V0 > V1 > V0 / 2. By setting V0 > V1, the water level of the aqueous adhesive 210 in the upright container body 220 is located below the upper end of the opening 235. This prevents the aqueous adhesive 210 from spilling out of the container body 220 even if the container body 220 is tilted slightly with the opening 235 open. Therefore, it becomes easier for the worker to transfer the aqueous adhesive 210 from the container body 220 to the container constituting the storage section 171. In addition, by setting V1 > V0 / 2, the maximum volume V0 of the container 240 can be utilized efficiently.

[0119] And in the initial state, the following equation (1) is satisfied. V2 / (V1+V2)×100≦18[vol%] ···(1) In the following, V2 / (V1+V2)×100 will also be referred to as the "proportion of gas."

[0120] According to the inventors' studies, when the above formula (1) is satisfied, the formation of aggregates (hereinafter simply referred to as "aggregates"), which are clumps formed by the aggregation of adhesive particles in the aqueous adhesive 210 in the container 240, can be suppressed. The following reasons are considered to be for this: The lower the amount of water in the aqueous adhesive 210, the higher the concentration of adhesive particles becomes, making them more prone to aggregation and thus more likely to form aggregates. In this embodiment, by keeping the proportion of gas in the container 240 relatively low, the evaporation of water from the aqueous adhesive 210 in the container 240 can be suppressed. Therefore, the amount of water in the aqueous adhesive 210 in the container 240 can be kept at an appropriate level, and the state in which the adhesive particles are dispersed in water can be kept in good condition. As a result, the formation of aggregates can be suppressed.

[0121] Furthermore, if aggregates exist in the coating liquid 12 applied to the surface 111s of the transport member 111, these aggregates may get caught on the blade 170b, causing concave streaks (recesses) to form in the coating film 13 downstream of the point where the aggregates are caught on the blade 170b, or causing protrusions on the coating film 13 due to aggregates that pass through the blade 170b. As a result, uneven thickness areas such as recesses and protrusions will occur in the adhesive layer 11 after the coating film 13 has dried. When a recording medium W is adhered to such an adhesive layer 11, the surface (printed surface) of the recording medium W will conform to the surface of the adhesive layer 11, resulting in recesses and protrusions on the surface of the recording medium W. When printing is performed on such a surface of the recording medium W, there is a possibility that printing defects will occur near the recesses and protrusions on the recording medium W.

[0122] In contrast, in this embodiment, by suppressing the generation of aggregates, it becomes easier to form a smooth adhesive layer 11 on the surface 111s of the transport member 111. As a result, when the recording medium W adheres to the adhesive layer 11, the surface of the recording medium W can be made smooth. Since printing can be performed on a recording medium W with a smooth surface, the quality of the print applied to the recording medium W can be made appropriate and of high quality.

[0123] Furthermore, it is preferable that the following equation (2) is also satisfied in the initial state. V2 / (V1+V2)×100≦9[vol%] ···(2) According to the inventors' studies, when formula (2) above is satisfied, not only can the formation of aggregates in the aqueous adhesive 210 in the container 240 be suppressed, but the adhesive strength and durability of the adhesive layer 11 formed using this aqueous adhesive 210 can also be improved. The following reasons can be considered for this: When the proportion of gas is below the above upper limit, the evaporation of water from the aqueous adhesive 210 in the container 240 can be further suppressed, so the amount of water in the aqueous adhesive 210 in the container 240 can be maintained more appropriately. As a result, the state in which the adhesive particles are dispersed in water in the aqueous adhesive 210 in the container 240 can be maintained more effectively. As a result, the uneven distribution of adhesive particles in the coating liquid 12 and coating film 13 using this aqueous adhesive 210 can be suppressed, and a homogeneous adhesive layer 11 can be formed on the surface 111s of the transport member 111. As a result, the adhesive strength and durability of the adhesive layer 11 can be improved. This allows the transport member 111 to stably transport the recording medium W. As a result, when printing is performed on the recording medium W while it is being transported, the printing will be proper and of high quality.

[0124] In this embodiment, the container 240 contains an amount of aqueous adhesive 210 sufficient to form the adhesive layer 11 at least once. Therefore, even after replenishing the water-based adhesive 210 in the storage section 171 using the aqueous adhesive container 200, some aqueous adhesive 210 may remain in the container 240. In such cases, the aqueous adhesive container 200 will be stored until the next time the water-based adhesive 210 is replenished in the storage section 171.

[0125] Figure 6 is a cross-sectional view showing the state in which the volume V1 of the aqueous adhesive 210 in the container 240 has decreased from the state in Figure 4.

[0126] As shown in Figure 6, when a portion of the aqueous adhesive 210 in the container 240 is removed from the initial state, and the volume V1 of the aqueous adhesive 210 in the container 240 decreases to V1 = V0 / 2, it is preferable, and more preferable, that equation (1) is satisfied due to the deformation of the sheet material, and it is preferable that equation (2) is satisfied.

[0127] Specifically, as shown in Figures 4 and 6, when a portion of the aqueous adhesive 210 is discharged from the mouth 235 of the container 240, the sheet material is flexible, so for example, the upper parts of a pair of side sheets 231 and 232 move closer together, and the volume of the container body 220 (internal space S1) contracts. As a result, the volume V1 of the aqueous adhesive 210 in the container 240 decreases, as does the volume V2 of the gas in the container 240. Therefore, when the container 240 with residual aqueous adhesive 210 is stored, the formation of aggregates in the aqueous adhesive 210 remaining in the container 240 can be suppressed. Thus, the aqueous adhesive 210 remaining in the container 240 can be used for forming the adhesive layer 11 after being stored for a while.

[0128] Furthermore, if the aqueous adhesive 210 is further discharged from the mouth 235 of the container 240 from the state shown in Figure 6, the lower parts of the pair of side sheets 231 and 232 will move closer together, and the bottom sheet 233 will return to its folded state. That is, the lower end 233a on the x-axis-- side and the lower end 233b on the x-axis-+ side will move closer together. As a result, the volume (internal space S1) of the container body 220 will further shrink. Therefore, as shown in Figures 4 and 6, if the volume V1 of the aqueous adhesive 210 inside the container body 220 is relatively large, the container body 220 will be able to stand on its own, and if the volume V1 of the aqueous adhesive 210 inside the container body 220 is relatively small, the volume (internal space S1) of the container body 220 can be easily shrunk. In this embodiment, the bag-shaped portion of the container body 220 is composed of a flexible sheet material almost entirely, but is not limited to this. For example, the bag-shaped portion of the container body 220 may be made partly of a flexible sheet material, while the other parts are made of a rigid material (rigid body).

[0129] The maximum volume V0 of the container 240 is not particularly limited, but is preferably 0.2L or more and 5L or less, and more preferably 0.5L or more and 1.5L or less. By setting the maximum volume V0 to be above the lower limit, a sufficient amount of aqueous adhesive 210 to form the adhesive layer 11 at least once can be contained in the container 240. Furthermore, by setting the maximum volume V0 to be below the upper limit, it becomes easier to carry the aqueous adhesive container 200 and to transfer the aqueous adhesive 210 from the container body 220 to the storage section 171.

[0130] Furthermore, the volume V1 of the aqueous adhesive 210 in the container 240 in its initial state is not particularly limited, but is preferably 0.2 L or more and 5 L or less, and more preferably 0.5 L or more and 1.5 L or less. By setting the volume V1 to be above the lower limit, a sufficient amount of aqueous adhesive 210 to form the adhesive layer 11 at least once can be contained in the container 240. Also, by setting the volume V1 to be below the upper limit, it becomes easier to carry the aqueous adhesive container 200 and to transfer the aqueous adhesive 210 from the container body 220 to the storage section 171.

[0131] The initial volume V2 of the gas in the container 240 is not particularly limited, but is preferably 0 L or more and 0.9 L or less, and more preferably 0 L or more and 0.2 L or less. By setting the volume V2 within the above range, the formation of aggregates in the aqueous adhesive contents 200 in the container 240 can be suppressed.

[0132] The relationship between the maximum volume V0, the volume V1 of the aqueous adhesive container 200, and the volume V2 of the gas is not limited to the above. For example, in the initial state, V1 = V0 (V2 = 0), or V1 ≤ V0 / 2.

[0133] Furthermore, the water vapor permeability of the sheet material at 1 atm, 40°C, and 90% RH is not particularly limited, but is 3 [g / m²]. 2 ·day] or more than 150[g / m 2 It is preferable that it is less than or equal to 3 [g / m³] 2 ·day] or more than 100[g / m 2It is more preferable that it is less than or equal to 3 [g / m³]. 2 ·day] or more than 90[g / m 2 It is even more preferable that it be less than or equal to [day]. The water vapor permeability of the sheet material is measured in accordance with JIS K7129:2008.

[0134] According to the inventors' studies, when the water vapor permeability of the sheet material is below the above upper limit, the generation of aggregates in the aqueous adhesive 210 in the container 240 can be suppressed, and the adhesive strength and durability of the adhesive layer 11 formed using this aqueous adhesive 210 can be improved. The following reasons are considered to be for this: When the water vapor permeability of the sheet material is within the above range, the leakage of water vapor contained in the gas inside the container 240 to the outside can be suppressed. This suppresses the evaporation of water from the aqueous adhesive 210 inside the container 240. Therefore, the amount of water in the aqueous adhesive 210 inside the container 240 can be kept at an appropriate level, and the state in which the adhesive particles are dispersed in water can be kept in good condition in the aqueous adhesive 210 inside the container 240. As a result, the generation of aggregates can be suppressed, and the uneven distribution of adhesive particles in the coating liquid 12 and coating film 13 using this aqueous adhesive 210 can be suppressed, and a homogeneous adhesive layer 11 can be formed on the surface 111s of the transport member 111. This improves the adhesive strength and durability of the adhesive layer 11. As a result, the transport member 111 can stably transport the recording medium W. Consequently, when printing is applied to the recording medium W during transport, the printing becomes proper and of high quality.

[0135] Furthermore, the oxygen permeability of the sheet material at 1 atm, 20°C, and 90% RH is not particularly limited, but is approximately 0.5 [ml / (m²). 2 (·day·MPa) or more 3000 [ml / (m 2 It is preferable that it be less than or equal to 0.5 [ml / (m³)]. 2 (·day·MPa) or more 2500 [ml / (m 2 It is more preferable that it be less than or equal to 0.5 [ml / (m³)]. 2 (·day·MPa) or more 1900 [ml / (m 2It is even more preferable that the oxygen permeability of the sheet material is less than or equal to (·day·MPa). The oxygen permeability of the sheet material is measured in accordance with JIS K7126-1:2006.

[0136] According to the inventors' studies, when the oxygen permeability is below the above upper limit, the generation of aggregates in the aqueous adhesive 210 inside the container 240 can be suppressed, and the adhesive strength and durability of the adhesive layer 11 formed using this aqueous adhesive 210 can be improved. The following reasons are considered to be for this: When the oxygen permeability is below the above upper limit, oxygen from the air outside the container 240 can be prevented from entering the container 240. Therefore, an increase in the proportion of gas inside the container 240 can be suppressed, and the evaporation of water from the aqueous adhesive 210 inside the container 240 can be suppressed. Therefore, the amount of water in the aqueous adhesive 210 inside the container 240 can be maintained appropriately, and the state in which the adhesive particles are dispersed in water can be maintained well in the aqueous adhesive 210 inside the container 240. As a result, the generation of aggregates can be suppressed, and uneven distribution of adhesive particles in the coating liquid 12 and coating film 13 using this aqueous adhesive 210 can be suppressed, and a homogeneous adhesive layer 11 can be formed on the surface 111s of the transport member 111. This improves the adhesive strength and durability of the adhesive layer 11. As a result, the transport member 111 can stably transport the recording medium W. Consequently, when printing is applied to the recording medium W during transport, the printing becomes proper and of high quality.

[0137] The average thickness of the sheet material is not particularly limited, but is preferably 50 μm to 2000 μm, more preferably 80 μm to 1000 μm, and even more preferably 100 μm to 400 μm. By keeping the average thickness of the sheet material within the above range, it is possible to improve the gas barrier properties while maintaining a good balance between the strength and flexibility of the sheet material.

[0138] The sheet material is preferably visible to the aqueous adhesive 210 it contains. That is, the sheet material is preferably colorless and transparent, colored and transparent, or semi-transparent. This allows the user to easily grasp the remaining amount of aqueous adhesive 210 in the container 240 and its condition (properties). Furthermore, the aqueous adhesive 210 is an emulsion in which adhesive particles are dispersed in water, and appears white to the user under white lighting. Therefore, when a colorless and transparent sheet material is used, the user can easily distinguish between a container 240 containing white aqueous adhesive 210 and a container containing ink of a color such as cyan (C), magenta (M), yellow (Y), or black (K).

[0139] The visible light transmittance of the sheet material is not particularly limited, but is preferably 35% to 99%, more preferably 50% to 99%, and even more preferably 60% to 99%. The visible light transmittance of the sheet material is measured in accordance with JIS K7361-1:1997. The sheet material having sufficient visibility for the contained aqueous adhesive 210 is not particularly limited, but examples include resin sheets such as polystyrene (PS) and polyethylene phthalate (PET).

[0140] As described above, the aqueous adhesive container 200 according to this embodiment comprises an aqueous adhesive 210 containing water and adhesive particles, which is applied to the surface 111s of a transport member 111 that transports the recording medium W of the printing apparatus 100, and a container 240 that contains the aqueous adhesive 210. The container 240 contains the aqueous adhesive 210 and comprises a container body 220 made of a flexible sheet material with a mouth 235 formed therein, and a lid member 230 that is attached to the mouth 235 so as to be able to open and close the mouth 235. When the ambient environment around the container 240 is 25°C and 1 atm, and the volume of the aqueous adhesive 210 contained in the container 240 is V1, and the volume of gas present in the container 240 is V2, the following formula (1) is satisfied when the container 240 is in its initial unopened state. V2 / (V1+V2)×100≦18[vol%] ···(1)

[0141] This prevents the formation of aggregates of adhesive particles in the aqueous adhesive 210 within the container 240 when the aqueous adhesive container 200 is being stored. As a result, the surface of the adhesive layer 11 formed using this aqueous adhesive 210 can be smoothed. Consequently, the occurrence of printing defects can be suppressed. Furthermore, since the container 240 is made of a flexible sheet material, when a portion of the aqueous adhesive 210 in the container 240 is removed from its initial state, the deformation of the sheet material reduces the volume V1 of the aqueous adhesive 210 in the container 240, and also easily reduces the volume V2 of the gas in the container 240. Then, by closing the opening 235 with the lid member 230, the aqueous adhesive container 200 can be stored again in a state where aggregates are less likely to form inside the container 240.

[0142] Furthermore, when the maximum volume of container 240 is V0, in the initial state V0≧V1>V0 / 2. By removing a portion of the aqueous adhesive 210 from container 240 from the initial state, the volume V1 of the aqueous adhesive 210 in container 240 decreases, and when V1=V0 / 2, the deformation of the sheet material satisfies equation (1). As a result, when the aqueous adhesive 210 of the aqueous adhesive container 200 is partially used and the remaining aqueous adhesive 210 is stored in container 240, the formation of aggregates in the remaining aqueous adhesive 210 can be suppressed. Therefore, the surface of the adhesive layer 11 formed using this remaining aqueous adhesive 210 can be smoothed, and the decrease in adhesive strength and unevenness of adhesive strength due to the aggregation of adhesive particles can be suppressed. As a result, when printing is performed on the recording medium W being transported by the transport member 111, the occurrence of printing defects can be suppressed, and the print quality can be improved.

[0143] Furthermore, in the initial state, the following equation (2) is satisfied. V2 / (V1+V2)×100≦9[vol%] ···(2) This prevents the formation of aggregates in the aqueous adhesive 210 inside the container 240 during storage, etc. As a result, the printing quality of the printing device 100 can be made appropriate and of high quality.

[0144] Furthermore, the water vapor transmission rate of the sheet material at 1 atm, 40°C, and 90% RH is 3 [g / m²]. 2 ·day] or more than 150[g / m 2 The duration is less than or equal to [day]. This suppresses the formation of aggregates in the aqueous adhesive 210 inside the container 240 during storage, and when the adhesive layer 11 is formed using this aqueous adhesive 210, the adhesive strength and durability of the adhesive layer 11 can be improved. As a result, the print quality of the printing device 100 can be made appropriate and of high quality.

[0145] Furthermore, the oxygen permeability of the sheet material at 1 atm, 20°C, and 90% RH is 0.5 [ml / (m²). 2 (·day·MPa) or more 3000 [ml / (m 2 The pressure is less than or equal to (·day·MPa). This suppresses the formation of aggregates in the aqueous adhesive 210 inside the container 240 during storage, and when the adhesive layer 11 is formed using this aqueous adhesive 210, the adhesive strength and durability of the adhesive layer 11 can be improved. As a result, the printing quality of the printing device 100 can be made appropriate and of high quality.

[0146] Furthermore, the resin constituting the adhesive particles includes a (meth)acrylic resin. This improves the adhesive strength and durability of the adhesive layer 11. As a result, the printing quality of the printing device 100 can be made appropriate and of high quality.

[0147] Furthermore, the viscosity of the aqueous adhesive 210 at 25°C is between 2 mPa·s and 15 mPa·s. This facilitates the formation of a uniform thickness of the aqueous adhesive 210 (coating liquid 12) applied to the surface 111s of the conveying member 111, contributing to the uniformity of the thickness of the adhesive layer 11 obtained from the aqueous adhesive 210 and the homogenization of its surface properties.

[0148] Furthermore, the average particle size of the adhesive particles is between 50 nm and 300 nm. This allows the adhesive particles to be sufficiently dispersed in the aqueous adhesive 210, and this good dispersion state of the adhesive particles can be maintained even in the coating film 13 formed to a predetermined thickness on the surface 111s of the transport member 111. As a result, a uniform and homogeneous adhesive layer 11 can be formed, and the adhesive strength and durability of the adhesive layer 11 can be made excellent. Consequently, the printing quality of the printing device 100 can be made appropriate and of high quality.

[0149] Furthermore, the solid content in the aqueous adhesive 210 is between 20% by mass and 60% by mass. This enhances the adhesive strength and durability of the adhesive layer 11 while effectively suppressing the formation of aggregates in the aqueous adhesive 210.

[0150] Furthermore, the sheet material is visible to the water-based adhesive 210 contained in the container 240. This allows the user to easily ascertain the remaining amount of water-based adhesive 210 in the container 240 and its condition (properties).

[0151] In this invention, the conveying member that applies the aqueous adhesive is not limited to the endless belt that rotates in a circular motion as described above. For example, the conveying member may travel in one direction or reciprocate to convey the recording medium.

[0152] Although the printing apparatus and aqueous adhesive container according to embodiments of the present invention have been described above, the present invention is not limited thereto. Furthermore, each part of the printing apparatus and aqueous adhesive container can be replaced with any structure capable of performing similar functions. In addition, any structure may be added. [Examples]

[0153] Next, we will describe some examples. Figure 7 is Table 1, showing the mixing ratio and physical properties of the (meth)acrylic monomers constituting the adhesive particles of aqueous adhesive 1 and aqueous adhesive 2. Figure 8 is Table 2, showing the composition and evaluation of the aqueous adhesive containers of Examples 1 to 13 and Comparative Examples 1 and 2.

[0154] 1. Manufacturing of water-based adhesives 114 g of deionized water was added to a reactor equipped with a stirrer, reflux condenser, thermometer, nitrogen inlet tube, and dropping funnel, and the temperature was raised to 82°C. Then, a total of 497 g of (meth)acrylic monomer, adjusted to the mixing ratio described in the column for aqueous adhesive 1 in Table 1, 118 g of deionized water, and 13 g of Hythenol NF-08 (polyoxyethylene styrene-phenyl ether sulfate ammonium salt, nonionic surfactant, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) were added as adhesive particles and mixed and stirred. To the homogenized solution, 248 g of a 2% by mass aqueous solution of ammonium persulfate, a polymerization initiator, was added over 1.5 hours at 82°C.

[0155] After adding all the above materials, the mixture was kept warm for one hour and then cooled. Deionized water was added, along with ammonia water as a pH adjuster. The mixture was then filtered through a 150-mesh nylon filter to remove coarse particles, yielding aqueous adhesive 1 (average particle size 220 nm, solid content 45% by mass). Aqueous adhesive 2 (average particle size 200 nm, solid content 45% by mass) was obtained using the same method.

[0156] 200 mL each of the prepared aqueous adhesive 1 and aqueous adhesive 2 were placed in a stirring container and stirred for 20 minutes while the temperature was adjusted to 25°C. The viscosity at 25°C was then measured using a B-type viscometer. The results are shown in Table 1.

[0157] 2. Containing the water-based adhesive into a container. Next, aqueous adhesive 1 and aqueous adhesive 2 were each placed in containers with the configurations shown in Table 2, such that the gas ratio V2 / (V1+V2)×100 was the value shown in Table 2, and the mouths of each container were sealed. This yielded the aqueous adhesive contents of Examples 1 to 13 and Comparative Examples 1 and 2. In Examples 1 to 13 and Comparative Example 1, the container structure was a bag-like structure using a flexible sheet material. Of these, the sheet material constituting the containers of Examples 1 to 5, 7 to 12 and Comparative Example 1 consisted of a single resin layer, while the sheet material constituting the containers of Examples 6 and 13 consisted of a laminate of three resin layers. In all cases, the sheet material had a thickness of 250 μm and provided internal visibility (visible light transmission). The resin layer materials constituting the sheet material are as shown in Table 2. In Comparative Example 2, the container structure was a rigid polypropylene bottle.

[0158] 3. Evaluation Next, each aqueous adhesive sample was left in an ambient environment of 60°C and 50% RH for 14 days, and then evaluated for three criteria: aggregation, adhesive strength, and durability.

[0159] [Cohesion] 100 mL of aqueous adhesive from each aqueous adhesive container that had been left standing was filtered using a nylon mesh filter with a mesh size of 45 μm and a φ47 filter, and the time required for filtration (hereinafter also referred to as "filtration time") was measured. The presence or absence of aggregates was also checked visually. Then, the aggregates in each aqueous adhesive container were evaluated using the evaluation criteria shown below, based on the filtration time and whether or not aggregates were observed visually. The results are shown in Table 2.

[0160] (Evaluation Criteria) A1: Filtration time is 15 seconds or less, and no aggregates are visible to the naked eye. B1: Filtration time is between 15 and 30 seconds, and no aggregates are visible to the naked eye. C1: Filtration time exceeds 30 seconds, and aggregates are visually observed.

[0161] [Adhesive strength] The aqueous adhesive from each aqueous adhesive container, which had been left to stand, was applied to a glass substrate to form a 200 μm thick coating, and the coating was dried to form an adhesive layer. A 50 mm wide cotton fabric was then attached to this adhesive layer at 23°C with a pressure of 1.0 kgf / 50 mm, and the 90-degree peel force when removing the cotton fabric was measured as the adhesive force. The tackiness of each aqueous adhesive container was then evaluated using the evaluation criteria based on the measured adhesive force shown below. The results are shown in Table 2.

[0162] (Evaluation Criteria) A2: Adhesive strength of 1.0 [N / 50mm] or more and less than 2.0 [N / 50mm] B2: Adhesive strength of 0.5 [N / 50mm] or more and less than 1.0 [N / 50mm] C2: Adhesion strength of 0.3 [N / 50mm] or more and less than 0.5 [N / 50mm]

[0163] [Durability] The aqueous adhesive from each aqueous adhesive container, which had been left to stand, was applied to a glass substrate to form a 200 μm thick coating, and the coating was dried to form an adhesive layer. The adhesive layer thus prepared was then subjected to a durability test by pressing it against a rotating roller-shaped nylon brush moistened with water. Specifically, the nylon brush used was made of 6-10 nylon with a bristle length of 50 mm and a bristle diameter of 0.5 mm, implanted in a stainless steel cylinder with a diameter of 200 mm. This nylon brush was pressed against the adhesive layer with a pressing force of 1.0 N / cm and rotated at a rotation speed of 6 rpm, and this condition was maintained at 23°C for 30 days. After this durability test, a 50 mm wide cotton fabric was attached to the adhesive layer at 23°C with a force of 1.0 kgf / 50 mm, and the 180-degree peel force when peeling off the cotton fabric was measured as the adhesive force. The durability of the adhesive force of each aqueous adhesive container was then evaluated using the evaluation criteria based on the measured adhesive force after the durability test, as shown below. The results are shown in Table 2.

[0164] (Evaluation Criteria) A3: Adhesive strength of 0.4 [N / 50mm] or higher B3: Adhesive strength of 0.1 [N / 50mm] or more and less than 0.4 [N / 50mm] C3: Adhesion strength of 0.05 [N / 50mm] or more and less than 0.1 [N / 50mm]

[0165] 4.Results As shown in Table 2, aggregates were observed visually in the aqueous adhesive containers of Comparative Examples 1 and 2, where the gas content was 20 [vol%], and the aggregates received a C1 rating. On the other hand, no aggregates were observed visually in the aqueous adhesive containers of Examples 1 to 13, where the gas content was 18 [vol%] or less, and the aggregates received a B1 rating or higher. From the above, it was found that the generation of aggregates is suppressed when V2 / (V1+V2)×100 ≤ 18 [vol%].

[0166] Furthermore, for the aqueous adhesive-containing materials of Examples 3 to 6 and 11 to 13, where the gas content was 9 [vol%] or less, not only did the aggregates receive a rating of B1 or higher, but the adhesive strength also received a rating of B2 or higher, and the durability also received a rating of B3 or higher. From the above, it was found that V2 / (V1+V2)×100≦9 [vol%] is preferable for suppressing aggregates, improving the adhesive strength of the adhesive layer, and improving its durability.

[0167] Furthermore, the water vapor permeability of the sheet material is 180 [g / (m²]. 2 In Example 1 of the (day) aqueous adhesive containment, the adhesive strength was C2 and the durability was C3, while the water vapor permeability of the sheet material was 70 [g / (m 2 In the aqueous adhesive-containing materials of Examples 2, 3, and 4 of (day), the adhesive strength was B2 or higher, and the durability was B3 or higher. Therefore, the water vapor permeability of the sheet material was 150 [g / (m²]. 2 It was found that a value of less than or equal to (day) is preferable for improving the adhesive strength and durability of the adhesive layer.

[0168] Furthermore, the oxygen permeability of the sheet material is 3750 [g / (m²]. 2In Example 8 of the aqueous adhesive-containing material (·day·MPa), the adhesive strength was C2 and the durability was C3, while the oxygen permeability of the sheet material was 1500 [g / (m²]. 2 In the aqueous adhesive contents of Examples 5 and 9 (·day·MPa), the adhesive strength was B2 or higher, and the durability was B3 or higher. Therefore, the oxygen permeability of the sheet material was 3000 [g / (m²). 2 It was found that a value of less than or equal to (·day·MPa) is preferable for improving the adhesive strength and durability of the adhesive layer.

[0169] Furthermore, V2 / (V1+V2)×100≦12[vol%], and the water vapor permeability of the sheet material is 150[g / (m²). 2 (·day) or less, and the oxygen permeability of the sheet material is 3000 [g / (m²) 2 Examples 3 to 6 and 9 to 13, which were below (·day·MPa), showed aggregates of B1 or higher, adhesive strength of B2 or higher, and durability of B3 or higher. Therefore, V2 / (V1+V2)×100≦12[vol%] and the water vapor permeability of the sheet material was 150[g / (m 2 (·day) or less, and the oxygen permeability of the sheet material is 3000 [g / (m²) 2 It was found that a value of less than or equal to (·day·MPa) is preferable for suppressing aggregate formation and improving the adhesive strength and durability of the adhesive layer. [Explanation of Symbols]

[0170] 11...Adhesive layer, 12...Coating liquid, 13...Coating film, 100...Printing device, 110...Conveying device, 111...Conveying member, 111s...Surface, 112a...Driven roller, 112b...Driven roller, 113...Tensioner, 114...Tensioner, 120...Unwinding device, 121...Unwinding roller, 123...Tensioner, 130...Winding device, 131...Winding roller, 133...Tensioner, 134...Tensioner, 135...Tensioner, 140...Printing section, 141...Inkjet head, 142...Carriage unit, 150...Ink drying section, 160...Cleaning section, 161...Storage tank, 162...Cleaning brush, 170...Coating liquid supply section, 170a...Coating liquid supply source, 170b...Blade, 171...Storage section, 172...Liquid supply pipe, 17 3…Liquid pump, 180…Coating drying section, 200…Water-based adhesive container, 210…Water-based adhesive, 220…Container body, 230…Lid member, 231, Side sheet, 231a…Lower end, 231b…Upper end, 231c…Y-axis direction - side end, 231d…Y-axis direction + side end, 232…Side sheet, 232a…Lower end, 232b…Upper end, 232c…Y-axis direction - side end, 232d…Y-axis direction + side end, 233…Bottom sheet, 233a…X-axis direction - lower end, 233b…X-axis direction + lower end, 233c…Y-axis direction - side end, 233d…Y-axis direction + side end, 233f…Fold, 235…Mouth, 240…Container, S1…Internal space, S2…Internal space, V0…Maximum volume, V1…Volume, V2…Volume, W…Recording medium

Claims

1. An aqueous adhesive containing water and adhesive particles, which is applied to the surface of a transport member that transports a recording medium of a printing apparatus, A container for containing the aqueous adhesive, Equipped with, The aforementioned container is A container body comprising a flexible sheet material containing the aforementioned aqueous adhesive, and having an opening formed therein, A lid member is attached to the opening so as to be able to open and close the opening, It has, An aqueous adhesive container characterized in that, when the surrounding environment of the container is 25°C and 1 atm, V1 is the volume of the aqueous adhesive contained in the container and V2 is the volume of gas present in the container, the container satisfies the following formula (1) in its initial unopened state. V2 / (V1+V2)×100≦18[vol%]...(1)

2. When the maximum volume of the container is V0, in the initial state V0 ≥ V1 > V0 / 2, The aqueous adhesive container according to claim 1, wherein when a portion of the aqueous adhesive in the container is removed from the initial state, the volume V1 of the aqueous adhesive in the container decreases to V1 = V0 / 2, and the sheet material deforms to satisfy formula (1).

3. The aqueous adhesive container according to claim 1, which satisfies the following formula (2) in the initial state described above. V2 / (V1+V2)×100≦9[vol%]...(2)

4. The water vapor permeability of the sheet material at 1 atm, 40°C, and 90% RH is 3 [g / m²]. ２ ・day] or more 150 [g / m ２ The aqueous adhesive container according to any one of claims 1 to 3, wherein the number of days is less than or equal to [day].

5. The oxygen permeability of the sheet material at 1 atm, 20°C, and 90% RH is 0.5 [ml / (m²)]. ２ ・day・MPa) 3000 or more [ml / (m ２ The aqueous adhesive container according to any one of claims 1 to 3, wherein the pressure is less than or equal to [day MPa].

6. The aqueous adhesive container according to any one of claims 1 to 3, wherein the resin constituting the adhesive particles includes a (meth)acrylic resin.

7. The aqueous adhesive container according to any one of claims 1 to 3, wherein the viscosity of the aqueous adhesive at 25°C is 2 mPa·s or more and 15 mPa·s or less.

8. The aqueous adhesive-containing material according to any one of claims 1 to 3, wherein the average particle size of the adhesive particles is 50 nm or more and 300 nm or less.

9. The aqueous adhesive container according to any one of claims 1 to 3, wherein the solid content in the aqueous adhesive is 20% by mass or more and 60% by mass or less.

10. The aqueous adhesive container according to any one of claims 1 to 3, wherein the sheet material is visible to the aqueous adhesive contained in the container.

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