Liquid injection head and liquid injection device

Abstract

The user needs to know the appropriate time to replace the liquid spray head. [Solution] The liquid spray head comprises a flow path communicating with a nozzle for spraying liquid, a containment space, a first adhesive portion separating the flow path and the containment space, and a discharge material contained within the containment space that flows into the flow path when the first adhesive portion can no longer separate the flow path and the containment space.

Description

Technical Field

[0006] , ,

[0005] , , ,

[0001] The present invention relates to a liquid injection head and a liquid injection device.

Background Art

[0002] Conventionally, liquid injection heads that inject a liquid such as ink from nozzles have become widespread. For example, Patent Document 1 discloses that a plurality of flow path members constituting the flow path of a liquid injection head are joined to each other by an adhesive, thereby liquid-tightly connecting the flow paths formed in each of the plurality of joined flow path members.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The adhesive that joins the flow path members deteriorates by contacting the liquid flowing through the flow path, and there is a risk that the liquid in the flow path may leak out of the flow path member from the joined portion. However, in the conventional technology described above, there is a problem that the user of the liquid injection head cannot determine when to replace the liquid injection head.

Means for Solving the Problems

[0005] A liquid injection head according to a preferred aspect of the present disclosure includes a flow path communicating with a nozzle that injects a liquid, an accommodation space, a first adhesive portion that partitions the flow path and the accommodation space, and an outflow material that is accommodated in the accommodation space and flows out into the flow path when the first adhesive portion cannot partition the flow path and the accommodation space.

[0006] A liquid spray head according to a preferred embodiment of the present disclosure comprises a flow path communicating with a nozzle for spraying liquid, and a third adhesive portion disposed within the flow path, wherein the third adhesive portion includes a discharge material that flows into the flow path when the third adhesive portion dissolves into the liquid in the flow path.

[0007] A liquid injection device according to a preferred embodiment of the present disclosure comprises a liquid injection head having a first flow path member that constitutes a first flow path which is part of the flow path, a second flow path member that constitutes a second flow path which is part of the flow path, and a second bonding portion that bonds the first flow path member and the second flow path member together so as to connect the first flow path and the second flow path in a liquid-tight manner; an acquisition unit that acquires information on whether or not the filter is clogged with the discharged material; and an estimation unit that estimates the degree of deterioration of the second bonding portion based on the information acquired by the acquisition unit.

[0008] A liquid injection device according to a preferred embodiment of the present disclosure comprises a liquid injection head having a first flow path member that constitutes a first flow path which is part of the flow path, a second flow path member that constitutes a second flow path which is part of the flow path, and a second bonding portion that bonds the first flow path member and the second flow path member together so as to create a liquid-tight communication between the first flow path and the second flow path; an acquisition unit that acquires information on whether or not the color of the liquid flowing in the flow path is abnormal; and an estimation unit that estimates the degree of deterioration of the second bonding portion based on the information acquired by the acquisition unit. [Brief explanation of the drawing]

[0009] [Figure 1] A schematic diagram showing an example configuration of the inkjet system SYS according to the first embodiment. [Figure 2] A diagram showing the configuration of the processing unit 200. [Figure 3] A block diagram showing an example configuration of inkjet printer 100. [Figure 4] Configuration diagram of inkjet printer 100. [Figure 5] Exploded perspective view of the liquid injection head 30. [Figure 6]Cross-sectional view when the liquid injection head 30 is fractured along the line IV-IV in Figure 5. [Figure 7] A magnified view of the area around the ink hole 322 shown in Figure 6. [Figure 8] Cross-sectional view when the head unit Hn is broken along the X-axis direction, passing through the wiring hole 323. [Figure 9] A schematic plan view showing the inside of head unit Hn. [Figure 10] A plan view illustrating the internal flow channel Sn within the structure. [Figure 11] Side view of the internal supply channel S1a and internal discharge channel S2a within the internal channel Sn through which the first ink flows. [Figure 12] Side view of the internal supply channel S1b and internal discharge channel S2b of the internal channel Sn through which the second ink flows. [Figure 13] A diagram illustrating the containment space CA and the spilled material PS. [Figure 14] A diagram illustrating the functions of the SYS inkjet system. [Figure 15] A flowchart illustrating the operation of the SYS inkjet system. [Figure 16] A block diagram showing an example configuration of the inkjet printer 100a in the second embodiment. [Figure 17] A diagram showing a flowchart illustrating the operation of the inkjet system SYS in the second embodiment. [Figure 18] A block diagram showing an example configuration of the inkjet printer 100b in the third embodiment. [Figure 19] A diagram illustrating GLP (Good Laboratory Practice) for adhesive joints containing spillage material. [Figure 20] A diagram illustrating the GLPc adhesive portion containing the spill material in the first modified example. [Figure 21] A block diagram showing an example configuration of the inkjet printer 100d in the second modified example. [Figure 22] A diagram illustrating GLP (Good Laboratory Practice) for adhesive joints containing spillage material. [Figure 23]A diagram for explaining the accommodation space CAe in the third modification.

Embodiments for Carrying Out the Invention

[0010] Hereinafter, embodiments for implementing the present disclosure will be described with reference to the drawings. However, in each figure, the dimensions and scales of each part are appropriately different from the actual ones. Also, the embodiments described below are preferred specific examples of the present disclosure, and thus various technically preferable limitations are imposed. However, the scope of the present disclosure is not limited to these embodiments unless there is a description to specifically limit the present disclosure in the following description.

[0011] Hereinafter, for convenience of explanation, a direction along the X-axis from an arbitrary point will be denoted as the X1 direction, and a direction opposite to the X1 direction will be denoted as the X2 direction. The X1 direction and the X2 direction are collectively referred to as the direction along the X-axis. Similarly, directions opposite to each other along the Y-axis from an arbitrary point will be denoted as the Y1 direction and the Y2 direction, and directions opposite to each other along the Z-axis from an arbitrary point will be denoted as the Z1 direction and the Z2 direction. The Y1 direction and the Y2 direction are collectively referred to as the direction along the Y-axis. The Z1 direction and the Z2 direction are collectively referred to as the direction along the Z-axis. The direction along the X-axis and the direction along the Y-axis are perpendicular to each other. The direction along the X-axis and the direction along the Z-axis are perpendicular to each other. The direction along the Y-axis and the direction along the Z-axis are perpendicular to each other. The X-Y plane including the X-axis and the Y-axis corresponds to the horizontal plane. The Z-axis is an axis along the vertical direction, the Z1 direction corresponds to the upper side in the vertical direction, and the Z2 direction corresponds to the lower side in the vertical direction. Also, looking in the direction along the Z-axis may be described as "plan view".

[0012] 1. First Embodiment 1-1. Outline of Inkjet System SYS FIG. 1 is a schematic diagram showing a configuration example of an inkjet system SYS according to the first embodiment. The inkjet system SYS is a system that provides a service for forming an image on a medium PP (to be described later) by an inkjet method. The inkjet system SYS includes an inkjet printer 100 and a processing device 200.

[0013] Here, the inkjet printer 100 is a device provided by the manufacturer of the inkjet printer 100. The inkjet printer 100 is a liquid ejection device that ejects ink, which is an example of a liquid. The manufacturer of the inkjet printer 100 is the company that manufactures the inkjet printer 100. The manufacturer of the inkjet printer 100 may be referred to as the "printer manufacturer." The liquid ejection head 30 incorporated into the inkjet printer 100 is provided by the manufacturer of the liquid ejection head 30. The manufacturer of the liquid ejection head 30 is the company that manufactures the liquid ejection head 30. Hereafter, the manufacturer of the liquid ejection head 30 may be referred to as the "head manufacturer." The printer manufacturer receives the liquid ejection head 30 from the head manufacturer and manufactures the inkjet printer 100 by incorporating the provided liquid ejection head 30 into the inkjet printer 100. The inkjet printer 100 is an example of a "liquid ejection device."

[0014] Figure 1 shows a user U who uses the inkjet printer 100. User U is, for example, an employee belonging to the printer manufacturer who uses the inkjet printer 100. Also, for example, a third party who receives the inkjet printer 100 from the printer manufacturer and uses it is also a user U. In addition to the inkjet printer 100, user U also uses the processing unit 200.

[0015] The inkjet printer 100 receives image data (Img) from the processing unit 200. The inkjet printer 100 forms an image based on the image data (Img) onto the PP medium. Hereinafter, the process of forming an image onto the PP medium may be referred to as the "printing process."

[0016] The inkjet printer 100 has one head module 3, each having one liquid ejection head 30.

[0017] The processing unit 200 is a computer, such as a desktop or notebook computer. The processing unit 200 may also be provided as part of the inkjet printer 100.

[0018] 1-2. Regarding the malfunction of the liquid spray head 30 The liquid jet head 30 included in the inkjet printer 100 may malfunction due to aging or other reasons. One reason for the malfunction of the liquid jet head 30 is that the adhesive joint that connects the two flow path members that constitute the flow path within the liquid jet head 30 to ensure a liquid-tight connection between them may deteriorate due to prolonged contact with ink, wear from the flow rate, and / or leaching of the adhesive into the ink. This can lead to the inability to create a liquid-tight connection between the two flow path members, potentially causing ink to leak out of the flow path from the point where the connection is no longer liquid-tight. Hereinafter, the inability of the adhesive to seal the gap between the flow paths of the two flow path members may be referred to as "seal failure." When a seal failure occurs, ink may leak out of the flow path from the point where the seal failure occurred. If ink leaks out of the flow path, it may adhere to the electronic circuitry inside the liquid jet head 30, causing it to malfunction, or the inside or surrounding area of ​​the inkjet printer 100 may be contaminated with ink.

[0019] Therefore, the present invention provides a liquid spray head 30 that can detect signs of ink leakage from the liquid spray head 30 before the liquid spray head 30 malfunctions due to ink leaking out of the flow path from a point where a sealing failure has occurred. The signs of ink leakage from the liquid spray head 30 include the fact that ink will soon leak from the liquid spray head 30 and estimating the lifespan of the liquid spray head 30, that is, estimating the time when ink will likely leak from the liquid spray head 30.

[0020] 1-3. Configuration of the processing unit 200 Figure 2 shows the configuration of the processing unit 200. The processing unit 200 includes a control circuit 210, a memory circuit 220, an input device 260, and a display device 270. The control circuit 210, the memory circuit 220, the input device 260, and the display device 270 are interconnected by a bus 290 for communicating information.

[0021] The control circuit 210 includes, for example, one or more processors such as CPUs (Central Processing Units). The control circuit 210 may also include programmable logic devices such as FPGAs (Field Programmable Gate Arrays) in place of, or in addition to, the CPUs.

[0022] The memory circuit 220 is composed of a magnetic memory device or flash ROM, etc. The memory circuit 220 is readable by the control circuit 210 and stores multiple programs, including the inkjet program PM1 executed by the control circuit 210, and various information used by the control circuit 210. The memory circuit 220 includes, for example, one or more volatile memories such as RAM and one or more non-volatile memories such as ROM, EEPROM, or PROM, or both, as semiconductor memory. The inkjet program PM1 is, for example, a program that generates image data Img.

[0023] The communication device 240 is a circuit capable of communicating with the inkjet printer 100. For example, the communication device 240 is a network card such as USB (Universal Serial Bus) or Bluetooth. USB and Bluetooth are registered trademarks.

[0024] The input device 260 is a device that outputs operation information in response to user U's actions. The input device 260 is, for example, a mouse and a keyboard.

[0025] The display device 270 displays an image containing some information to the user U. The display device 270 is an organic EL (Electro-Luminescence) display, an LED (Light Emitting Diode) display, or an LCD (Liquid Crystal Display). Alternatively, the input device 260 and the display device 270 may be integrated into a single unit. An example of an integrated configuration of the input device 260 and the display device 270 is a touch panel.

[0026] 1-4. Overview of the Inkjet Printer 100 Figure 3 is a block diagram showing an example configuration of the inkjet printer 100. Figure 4 is a diagram of the inkjet printer 100's configuration. The inkjet printer 100 shown in Figure 4 is an inkjet printing device that sprays ink as droplets onto a medium PP. Ink is an example of a "liquid". The medium PP is, for example, printing paper. However, the medium PP is not limited to printing paper, and may be any material to be printed on, such as resin film or fabric.

[0027] As shown in Figures 3 and 4, the inkjet printer 100 includes a control module CM, a liquid supply system 10, a control circuit 21, a memory circuit 22, a transport mechanism 23, a moving mechanism 24, a head module 3, a communication device 28, and a flow meter 29.

[0028] The control module CM includes a power supply circuit 113 and a drive signal generation circuit 114. The power supply circuit 113 receives power from a commercial power supply (not shown) and generates various predetermined potentials. The generated potentials are supplied to various parts of the inkjet printer 100 as appropriate. In the example shown in Figure 3, the power supply circuit 113 generates a power supply potential VHV and an offset potential VBS. The offset potential VBS is supplied to the liquid jet head 30. The power supply potential VHV is supplied to the drive signal generation circuit 114, etc.

[0029] The drive signal generation circuit 114 is a circuit that generates a drive signal Com for driving the liquid injection head 30. Specifically, the drive signal generation circuit 114 includes, for example, a DA conversion circuit and an amplification circuit. In the drive signal generation circuit 114, the DA conversion circuit converts the waveform specification signal dCom from the control circuit 21 (described later) from a digital signal to an analog signal, and the amplification circuit generates the drive signal Com by amplifying the analog signal using the power supply potential VHV from the power supply circuit 113.

[0030] The liquid supply system 10 includes a liquid container 12 and a sub-tank 13. The liquid container 12 stores ink. The sub-tank 13 temporarily stores the ink supplied from the liquid container 12.

[0031] The liquid container 12 includes, for example, a cartridge that can be attached to or removed from the inkjet printer 100, a bag-shaped ink pack made of a flexible film, or an ink tank that can be refilled with ink. The liquid container 12 includes liquid containers 12a and 12b. Liquid containers 12a and 12b store, for example, inks of different colors. Liquid container 12a stores a first ink. Liquid container 12b stores, for example, a second ink of a different color from the first ink.

[0032] Subtank 13 includes subtanks 13a and 13b. Subtank 13a is connected to liquid container 12a and temporarily stores the first ink. Subtank 13b is connected to liquid container 12b and temporarily stores the second ink. A supply tube Ta_in and a discharge tube Ta_out are also connected to subtank 13a. A supply tube Tb_in and a discharge tube Tb_out are connected to subtank 13b. These tubes are connected to the head module 3. The subtank 13 supplies ink to the head module 3 and recovers ink from the head module 3. Thus, ink circulates between the subtank 13 and the head module 3.

[0033] The inks are, for example, water-based pigment inks, solvent inks, or UV-curable inks. Solvent inks are inks that contain an organic solvent. Solvent inks are inks that, after being applied to a medium PP, erode the medium PP to form a receiving layer, and fix the colorant on this receiving layer. UV-curable inks are inks that contain a UV-curing component. Hereinafter, UV-curable inks will be referred to as UV (Ultra Violet) inks. The UV-curing component contains a monomer or oligomer. UV inks are inks that, after being applied to a medium PP, are irradiated with ultraviolet light, causing the UV-curing component to harden, and fix the colorant within the film formed by the hardening of the UV-curing component.

[0034] The memory circuit 22 stores various programs, including the control program PM2 executed by the control circuit 21, and various data, such as image data Img, processed by the control circuit 21. The memory circuit 22 includes, for example, one or more volatile memories such as RAM and one or more non-volatile memories such as ROM, EEPROM, or PROM, or both, as semiconductor memory. The memory circuit 22 may be configured as part of the control circuit 21.

[0035] The transport mechanism 23 transports the medium PP along the Y-axis under the control of the control circuit 21. The moving mechanism 24 reciprocates the head module 3 along the X-axis under the control of the control circuit 21.

[0036] The moving mechanism 24 comprises a roughly box-shaped support 241 that houses the head module 3, and an endless belt 242 to which the support 241 is fixed.

[0037] The communication device 28 is a circuit capable of communicating with the processing unit 200. For example, the communication device 28 is a network card such as a USB or Bluetooth card. Alternatively, the communication device 28 may be integrated with the control circuit 21.

[0038] The head module 3 sprays ink supplied from the sub-tank 13 onto the medium PP under the control of the control circuit 21. As the medium PP is transported by the transport mechanism 23 and the support 241 moves back and forth, the head module 3 sprays ink onto the medium PP, forming an image on the surface of the medium PP. Any ink not sprayed from the head module 3 is discharged into the sub-tank 13. The head module 3 is equipped with one liquid spray head 30, but may be equipped with multiple liquid spray heads 30.

[0039] Let's return to the explanation in Figures 3 and 4. The control circuit 21 controls each element of the inkjet printer 100. The control circuit 21 includes, for example, one or more processing circuits such as a CPU or FPGA and one or more storage circuits such as semiconductor memory.

[0040] The control circuit 21 controls the operation of each part of the inkjet printer 100 by executing a program stored in the memory circuit 22. Here, the control circuit 21 generates signals such as control signal Sk1, control signal Sk2, print signal SI, waveform specification signal dCom, and request signal RI as signals to control the operation of each part of the inkjet printer 100.

[0041] Control signal Sk1 is a signal for controlling the drive of the moving mechanism 24. Control signal Sk2 is a signal for controlling the drive of the transport mechanism 23. Printing signal SI is a signal for controlling the drive of the liquid spray head 30. Waveform specification signal dCom is a digital signal for defining the waveform of the drive signal Com generated by the drive signal generation circuit 114.

[0042] The flow meter 29 measures the flow rate of the flow path within the liquid injection head 30. For example, the flow meter 29 is installed in the middle of the supply tube Ta_in or in the middle of the discharge tube Ta_out. In the example shown in Figure 3, the flow meter 29 is installed outside the liquid injection head 30, but the flow meter 29 may also be installed inside the liquid injection head 30. When the flow meter 29 receives a request signal RI from the control circuit 21, it generates flow information QI indicating the measured flow rate and transmits the flow information QI to the control circuit 21.

[0043] The liquid spray head 30 is provided with a containment space CA used to detect signs of ink leakage from the liquid spray head 30. The containment space CA contains the spill material PS. The containment space CA and the spill material PS will be explained with reference to Figure 13.

[0044] 1-5. Overall configuration of the liquid injection head 30 Figure 5 is an exploded perspective view of the liquid injection head 30. Figure 6 is a cross-sectional view of the liquid injection head 30 when it is broken along the line IV-IV in Figure 5. The diagram in Figure 6 is a view of the cross-section of the liquid injection head 30 when it is broken along the line IV-IV, as seen in the Y2 direction. The line IV-IV is a virtual line segment that passes through the two ink holes 322 and is aligned with the X-axis direction.

[0045] As shown in Figure 5, the liquid injection head 30 comprises a housing 3α, a flow channel structure 33, a fixing plate 36, and a reinforcing plate 37. The liquid injection head 30 also has a plurality of head units H1, H2, H3, and H4. When head units H1, H2, H3, and H4 are not distinguished, they are referred to as head unit Hn. The liquid injection head 30 also includes electrical elements such as a wiring board 381, wiring members 382, ​​circuit boards 383u, and 383v. The flow channel structure 33 has a laminate 333, supply connection parts 331a and 331b, and discharge connection parts 332a and 332b. The elements of the liquid injection head 30 will be described below with reference to Figures 5 and 6.

[0046] The housing 3α shown in Figures 5 and 6 is a hollow case that houses the head unit Hn and the laminate 333. The housing 3α has a cover member 31 and a holder member 32.

[0047] The cover member 31 houses the laminate 333. The holder member 32 houses a plurality of head units Hn. In this embodiment, the holder member 32 houses four head units Hn. The holder member 32 is positioned in the Z2 direction relative to the cover member 31.

[0048] As shown in Figure 5, the cover member 31 has two first connection holes 311, two second connection holes 312, and a first hole 313. The first hole 313 is a hole through which the wiring member 382 is inserted. One of the supply connection parts 331a and 331b is inserted and fitted into each first connection hole 311. One of the discharge connection parts 332a and 332b is inserted and fitted into each second connection hole 312.

[0049] The holder member 32 has a plurality of recesses 321, a plurality of ink holes 322, and a plurality of wiring holes 323. Each recess 321 is a recess that opens in the Z2 direction. A head unit Hn is placed in each recess 321. Each ink hole 322 is a hole through which ink flows between the flow path structure 33 and the head unit Hn. Each wiring hole 323 communicates with the recess 321. Each wiring hole 323 is a hole through which the flexible substrate 51 shown in Figure 8 passes. A flexible substrate 51 is provided for each head unit Hn and is electrically connected to the head unit Hn. Also, as shown in Figure 5, the holder member 32 has a flange 324 for fixing the holder member 32 to the support 241.

[0050] As shown in Figure 6, the housing 3α has an upper wall portion 34 and a side wall portion 35. The side wall portion 35 has a side wall 351u and a side wall 351v.

[0051] As shown in Figure 5, the laminated body 333 of the channel structure 33 has multiple channel plates Su1, Su2, Su3, Su4, and Su5, which are referred to as channel plates Su when not distinguished. Each channel plate Su is formed, for example, by injection molding of resin, but may also be formed of metal.

[0052] The flow path plates Su1 to Su5 are bonded to each other by adhesives that form bonding sections GL12, GL23, GL34, and GL45. Flow path plate Su5 is bonded to the holder member 32 in the Z1 direction by adhesives that form bonding section GL56. In the following description, the layers formed by adhesives within the liquid injection head 30 are collectively referred to as bonding sections GL. The bonding sections GL connect the two members in a liquid-tight manner. The adhesive that forms the bonding sections GL is, for example, an epoxy-based adhesive mainly composed of epoxy resin, but a silicone-based adhesive may also be used.

[0053] The liquid injection head 30 has a flow path SF inside that communicates with the nozzle Nz. The flow path SF includes internal supply flow paths S1a, S1b, internal discharge flow paths S2a, S2b, internal supply flow paths R1a, R1b, internal discharge flow paths R2a, R2b, a first liquid storage chamber Ra, a second liquid storage chamber Rb, second communication flow paths R4a, R4b, pressure chambers Ca, Cb, and first communication flow paths R3a, R3b. The adhesive portion GL that comes into contact with the ink is used as a seal for the flow path SF.

[0054] The laminate 333 has internal supply channels S1a and S1b, and internal discharge channels S2a and S2b. When the internal supply channels S1a, S1b, S2a, and S2b are not distinguished, they are referred to as internal channel Sn. Each internal channel Sn is a space formed within the laminate 333. Ink flows through each internal channel Sn. Each internal channel Sn is formed by one or both of the grooves along the XY plane provided in each of two adjacent channel plates Su, and by holes extending in the Z axis direction within the channel plate Su. Note that in Figure 6, the internal channel Sn is omitted to avoid complexity in the drawing.

[0055] Specifically, the internal supply channel S1a supplies the first ink stored in the sub-tank 13a to multiple head units Hn. The internal supply channel S1b supplies the second ink stored in the sub-tank 13b to multiple head units Hn. The internal discharge channel S2a discharges the first ink that was not ejected from the multiple head units Hn to the sub-tank 13a. The internal discharge channel S2b discharges the second ink that was not ejected from the multiple head units Hn to the sub-tank 13b. Each internal channel Sn may be equipped with filter chambers Fa and Fb, each having a filter FT for collecting foreign matter or air bubbles mixed in the ink.

[0056] Each of the supply connection parts 331a, 331b and discharge connection parts 332a, 332b is provided in the Z1 direction of the laminate 333 and protrudes from the laminate 333 in the Z1 direction. Each of the supply connection parts 331a, 331b and discharge connection parts 332a, 332b is a connecting pipe for connecting the flow path Sn within each structure to the outside of the housing 3α.

[0057] Specifically, the supply connection section 331a is a supply pipe that supplies first ink from the sub-tank 13a to the internal supply channel S1a, and is provided with a supply port S1a_in for supplying first ink to the laminate 333. The supply connection section 331b is a supply pipe that supplies second ink from the sub-tank 13b to the internal supply channel S1b, and is provided with a supply port S1b_in for supplying second ink to the laminate 333. The discharge connection section 332a is a discharge pipe that discharges first ink from the internal discharge channel S2a to the sub-tank 13a, and is provided with a discharge port S2a_out for discharging first ink from the laminate 333. The discharge connection section 332b is a discharge pipe that discharges second ink from the internal discharge channel S2b to the sub-tank 13b, and is provided with a discharge port S2b_out for discharging second ink from the laminate 333.

[0058] The head unit Hn has internal supply channels R1a and R1b, internal discharge channels R2a and R2b, and a liquid injection section Q for ejecting ink. The first liquid storage chamber Ra, the second liquid storage chamber Rb, the second communication channels R4a and R4b, the pressure chambers Ca and Cb, and the first communication channels R3a and R3b are included in the liquid injection section Q. The channels included in the liquid injection section Q are shown in Figure 8.

[0059] In Figure 6, the detailed shape of the liquid injection unit Q is omitted to avoid complexity in the drawing. The detailed shape of the liquid injection unit Q will be described later in Figure 8. Each head unit Hn has a plurality of nozzles Nz, as shown in Figure 6. Each nozzle Nz is a through-hole that sprays ink in the Z2 direction. Specifically, each head unit Hn has a plurality of nozzles Nz that spray first ink and a plurality of nozzles Nz that spray second ink. In addition, each head unit Hn defines the in-head supply passages R1a, R1b and the in-head discharge passages R2a, R2b.

[0060] The internal supply channels R1a and R1b are channels that extend from the Z1-direction end of the head unit Hn to the liquid injection section Q. The internal discharge channels R2a and R2b are channels that extend from the liquid injection section Q to the Z1-direction end of the head unit Hn. When the internal supply channels R1a and R1b and the internal discharge channels R2a and R2b are not distinguished, they are referred to as the internal channel Rn.

[0061] The head unit Hn has a case 335 that defines the internal flow path Rn within the head.

[0062] Figure 7 is a magnified view of the area around the ink hole 322 shown in Figure 6. The flow path plate Su5 has columnar protrusions 334a and 334b ​​that project in the Z2 direction. The protrusions 334a and 334b ​​are bonded to the holder member 32 in the Z1 direction by an adhesive that forms the bonding portion GL56.

[0063] The flow path plate Su5 has flow path plate side connecting pipes 330a and 330b. The flow path plate side connecting pipes 330a and 330b are collectively referred to as the flow path plate side connecting pipe 330. The flow path plate side connecting pipe 330 protrudes from the flow path plate Su5 toward the case 335 and is inserted into the ink hole 322.

[0064] Case 335 has case-side connecting pipes 336a and 336b. Case-side connecting pipes 336a and 336b are collectively referred to as case-side connecting pipe 336. Case-side connecting pipe 336 protrudes from case 335 toward the flow path plate Su5 and is inserted into the ink hole 322.

[0065] Adhesive is applied to the top surface of the flow path plate side connecting pipe 330 and the top surface of the case side connecting pipe 336 to form the adhesive joint GL57.

[0066] The direction of ink flow in the print head supply channels R1a and R1b is in the Z2 direction. The top surface of the channel plate side connecting pipe 330 and the top surface of the case side connecting pipe 336 are perpendicular to the direction of ink flow.

[0067] Let's return to the explanation in Figures 5 and 6. As shown in Figure 5, the fixing plate 36 is a plate member for fixing a plurality of head units Hn to the holder member 32. The fixing plate 36 has a plurality of openings 361 for exposing the nozzles Nz of the plurality of head units Hn.

[0068] The reinforcing plate 37 is positioned between the holder member 32 and the fixing plate 36 and is fixed to the fixing plate 36 with adhesive. The reinforcing plate 37 has a plurality of openings 371 in which the plurality of head units Hn are positioned.

[0069] The wiring board 381 is a mounting component for electrically connecting the liquid injection head 30 to the control circuit 21 shown in Figure 4. The wiring board 381 is placed on the laminate 333. A wiring member 382 is installed on the wiring board 381. The wiring member 382 is a component for electrically connecting the liquid injection head 30 and the control circuit 21. The wiring member 382 is, for example, a connector. The wiring member 382 may also be a signal cable such as an FFC (Flexible Flat Cable). Furthermore, the wiring board 381 and the wiring member 382 may be integrated.

[0070] The circuit boards 383u and 383v are arranged so as to sandwich the laminate 333. Each of the circuit boards 383u and 383v is electrically connected to the wiring board 381. The flexible circuit boards 51 mounted on each of the head units H1 and H3 are electrically connected to the circuit board 383u via an intermediate board (not shown). The flexible circuit boards 51 mounted on each of the head units H2 and H4 are electrically connected to the circuit board 383v via an intermediate board (not shown).

[0071] 1-6. Head Unit Hn Figure 8 is a cross-sectional view of the head unit Hn when it is broken along the X-axis direction, passing through the wiring hole 323. The diagram in Figure 8 is a view of the cross-section of the head unit Hn when it is broken along the X-axis direction, passing through the wiring hole 323, as seen in the Y2 direction. Figure 9 is a schematic plan view of the inside of the head unit Hn. The diagram in Figure 9 is a plan view of the inside of the head unit Hn as seen in the Z2 direction. Figures 8 and 9 each show the portion of the head unit Hn shown in Figure 6 near the fixing plate 36.

[0072] As shown in Figure 8, the head unit Hn comprises a nozzle plate 40, a communication plate 42, a pressure chamber substrate 43, a diaphragm 44, a plurality of drive elements E, a protective section 46, a compliance substrate 45, and the case 335 described above.

[0073] The nozzle plate 40, communication plate 42, pressure chamber substrate 43, and diaphragm 44 are each elongated plate-shaped members along the Y-axis. The pressure chamber substrate 43 and case 335 are positioned in the Z1 direction relative to the communication plate 42. On the other hand, the nozzle plate 40 and compliance substrate 45 are positioned in the Z2 direction relative to the communication plate 42. Furthermore, each component of the head unit Hn is joined to each other by adhesive. Although not shown in Figure 8, the layer formed by the adhesive that joins each component of the head unit Hn to each other is also included in the adhesive portion GL. The adhesive portion GL liquid-tightly connects the two components.

[0074] As shown in Figure 9, the multiple nozzles Nz are divided into a first nozzle row La and a second nozzle row Lb. Each of the first nozzle row La and the second nozzle row Lb is a set of multiple nozzles Nz arranged linearly along the Y axis. The first nozzle row La and the second nozzle row Lb are spaced apart from each other and aligned in the X axis direction. Here, the liquid injection unit Q has a first liquid injection unit Qa which includes multiple nozzles Nz belonging to the first nozzle row La, and a second liquid injection unit Qb which includes multiple nozzles Nz belonging to the second nozzle row Lb. The first liquid injection unit Qa injects first ink supplied from sub-tank 13a from each nozzle Nz of the first nozzle row La. The second liquid injection unit Qb injects second ink supplied from sub-tank 13b from each nozzle Nz of the second nozzle row Lb.

[0075] In the following description, the subscript 'a' is added to the symbols of elements related to the first nozzle row La, and the subscript 'b' is added to the symbols of elements related to the second nozzle row Lb. Furthermore, the elements related to the first liquid injection section Qa and the elements related to each nozzle Nz of the second liquid injection section Qb are arranged in a substantially plane-symmetrical manner. Therefore, in the following description, the elements corresponding to the first liquid injection section Qa will be explained in detail, and the explanation of the elements corresponding to the second liquid injection section Qb will be omitted as appropriate.

[0076] As shown in Figure 8, the communication plate 42 is provided with a first communication channel R3a and a second communication channel R4a. Each of the first communication channel R3a and the second communication channel R4a is provided for each nozzle Nz. The first communication channel R3a connects the nozzle Nz to the pressure chamber Ca described later. The second communication channel R4a connects the nozzle Nz to the first liquid storage chamber Ra described later. The compliance substrate 45 also constitutes a part of the wall surface of the first liquid storage chamber Ra. The compliance substrate 45 has, for example, a flexible resin film 45a and a metal plate 45b such as stainless steel.

[0077] Multiple pressure chambers Ca are provided in the pressure chamber substrate 43. Each pressure chamber Ca is a space that communicates with a nozzle Nz via a first communication channel R3a. An elastically deformable diaphragm 44 is positioned above each pressure chamber Ca. Part or all of the diaphragm 44 may be a separate component from the pressure chamber substrate 43, or it may be integrated with it. A drive element Ea is formed on the surface of the diaphragm 44 opposite to each pressure chamber Ca. Multiple drive elements Ea are arranged in a one-to-one correspondence with multiple nozzles Nz. The drive elements Ea generate energy for ejecting ink. Specifically, when a drive signal is applied to the drive element Ea, ink is ejected from the nozzle Nz. For example, the drive element Ea is a piezoelectric element that changes the volume of the pressure chamber Ca.

[0078] A protective section 46 is positioned on the diaphragm 44. A flexible substrate 51 is bonded to the surface of the diaphragm 44. Multiple wires for electrically connecting the control circuit 21 and the head unit Hn are formed on the flexible substrate 51. A drive circuit 50 for driving the drive elements E is also mounted on the flexible substrate 51. Based on the signal output from the control circuit 21, the drive circuit 50 selects whether or not to supply various signals, such as drive signals, to each drive element Ea to drive each drive element Ea.

[0079] Case 335 has a first liquid storage chamber Ra for storing ink. Case 335 also has parts of the head supply channels R1a, R1b, and R2a, R2b described above. As shown in Figure 8, the head supply channel R1a and the head discharge channel R2a are each connected to the first liquid storage chamber Ra. Also as shown in Figure 8, case 335 has a substrate hole 411 through which the flexible substrate 51 is inserted.

[0080] 1-7. Shape of the channel Sn within the structure Figure 10 is a plan view illustrating an internal flow path Sn within the structure. Figure 11 is a side view of the internal supply flow path S1a and the internal discharge flow path S2a within the internal flow path Sn through which the first ink flows. Figure 12 is a side view of the internal supply flow path S1b and the internal discharge flow path S2b within the internal flow path Sn through which the second ink flows. In Figures 11 and 12, the first liquid storage chamber Ra of each head unit Hn is indicated by the symbol "Ra / Hn", and the second liquid storage chamber Rb of each head unit Hn is indicated by the symbol "Rb / Hn". Note that the configuration of the internal flow path Sn is not limited to the following configurations.

[0081] The flow path structure 33 is provided with internal supply flow paths S1a and S1b, and internal discharge flow paths S2a and S2b, as illustrated in Figures 10, 11, and 12. The internal supply flow path S1a is a flow path from the supply port S1a_in to the internal supply flow path R1a of each head unit Hn, and the internal discharge flow path S2a is a flow path from the internal discharge flow path R2a of each head unit Hn to the discharge port S2a_out. The internal supply flow path S1b is a flow path from the supply port S1b_in to the internal supply flow path R1b of each head unit Hn, and the internal discharge flow path S2b is a flow path from the internal discharge flow path R2b of each head unit Hn to the discharge port S2b_out.

[0082] As illustrated in Figures 10 and 11, the internal supply channel S1a is a channel that includes a supply section Pa1, a connecting section Pa2, and four filter chambers Fa_1-Fa_4. As illustrated in Figure 11, the supply section Pa1 is formed between the channel plates Su1 and Su2. The supply section Pa1 has a shape that extends along the Y axis. The end of the supply section Pa1 in the Y2 direction communicates with the supply port S1a_in.

[0083] As illustrated in Figures 10 and 11, the internal supply channel S1a is a channel that includes a supply section Pa1, a connecting section Pa2, and four filter chambers Fa_1-Fa_4. As illustrated in Figure 11, the supply section Pa1 is formed between the channel plates Su1 and Su2. The supply section Pa1 has a shape that extends along the Y axis. The end of the supply section Pa1 in the Y2 direction communicates with the supply port S1a_in.

[0084] The connecting section Pa2 and the four filter chambers Fa_1 to Fa_4 are formed between the flow path plates Su2 and Su3. The connecting section Pa2 communicates with the supply section Pa1 through a through hole formed in the flow path plate Su2. The connecting section Pa2 extends in the Y2 direction from the connection point with the supply section Pa1, and branches into two systems that communicate with the filter chambers Fa_1 and Fa_3.

[0085] Filter chamber Fa_2 communicates with the supply unit Pa1 through a through-hole formed in the flow path plate Su2. Filter chamber Fa_4 communicates with the supply unit Pa1 through a through-hole formed in the flow path plate Su2. Each filter chamber Fa_1-Fa_4 communicates with the in-head supply flow path R1a of each head unit Hn through through-holes that penetrate the flow path plates Su3-Su5.

[0086] As illustrated in Figures 10 and 12, the internal supply channel S1b is a channel that includes a supply section Pb1, a connecting section Pb2, and four filter chambers Fb_1 to Fb_4. The supply section Pb1 is formed between the channel plates Su1 and Su2. The supply section Pb1 has a shape that extends along the Y axis. The end of the supply section Pb1 in the Y2 direction is connected to a supply port S1b_in. Here, the supply sections Pa1 and Pb1 are installed side by side between the channel plates Su1 and Su2.

[0087] The connecting section Pb2 and the four filter chambers Fb_1 to Fb_4 are formed between the flow path plates Su2 and Su3. The connecting section Pb2 communicates with the supply section Pb1 through a through hole formed in the flow path plate Su2. The connecting section Pb2 extends in the Y1 direction from the connection point with the supply section Pb1, and branches into two systems that communicate with the filter chambers Fb_2 and Fb_4. Here, the connecting section Pb2 extends in the opposite direction from the connecting section Pa2 from the connection point with the supply section Pb1.

[0088] Filter chamber Fb_1 communicates with the supply unit Pb1 through a through-hole formed in the flow path plate Su2. Filter chamber Fb_3 communicates with the supply unit Pb1 through a through-hole formed in the flow path plate Su2. Each filter chamber Fb_1-Fb_4 communicates with the in-head supply flow path R1b of each head unit Hn through through-holes that penetrate the flow path plates Su3-Su5.

[0089] As illustrated in Figures 10 and 11, the internal discharge channel S2a of the structure is a channel that includes a discharge section Pa3. The discharge section Pa3 is formed between the channel plates Su4 and Su5. The discharge section Pa3 has a shape that extends along the Y-axis over a wider area than the supply section Pa1. The vicinity of the end of the discharge section Pa3 in the Y1 direction communicates with the discharge port S2a_out. The internal discharge channel R2a of each head unit Hn communicates with the discharge section Pa3 through a through hole that penetrates the channel plate Su5.

[0090] As illustrated in Figures 10 and 12, the internal discharge channel S2b of the structure is a channel that includes a discharge section Pb3. The discharge section Pb3 is formed between the channel plates Su3 and Su4. The discharge section Pb3 has a shape that extends along the Y-axis over a wider area than the supply section Pb1. The vicinity of the end of the discharge section Pb3 in the Y1 direction communicates with the discharge port S2b_out. The internal discharge channel R2b of each head unit Hn communicates with the discharge section Pb3 through through holes that penetrate the channel plates Su4 and Su5.

[0091] 1-8. Containment space CA and spillage material PS In order to detect signs of ink leakage from the flow path of the liquid spray head 30 to the outside, in the first embodiment, a containment space CA is provided upstream of the filter chamber Fa, and the containment space CA is partitioned from the flow path SF by a fragile adhesive part GLW which is intentionally weaker than the adhesive part GL. The containment space CA contains the leaked material PS that flows into the flow path SF when the fragile adhesive part GLW collapses and it is no longer possible to partition the flow path SF from the containment space CA. When the leaked material PS flows into the flow path SF, the filter FT becomes clogged and the flow resistance of the flow path SF increases sharply. Generally, when the flow resistance increases, the flow rate decreases. Therefore, in the first embodiment, the flow rate can be periodically measured by the flow meter 29, and the collapse of the fragile adhesive part GLW can be detected by detecting a sharp decrease in the flow rate, i.e., a sharp increase in the flow resistance. In the first embodiment, the flow rate information QI indicating the flow rate is information regarding whether or not the filter FT is clogged with the leaked material PS.

[0092] Figure 13 is a diagram illustrating the containment space CA and the outflow material PS. In Figures 13 and subsequent figures, the shape of the flow channel structure 33, the flow channels within the flow channel structure 33, the shape of the head unit Hn, and the shape of the flow channels inside the head unit Hn are shown in a simplified manner to avoid complexity in the drawings. Figure 13 shows a cross-section of the flow channel structure 33 and the head unit Hn, cut along a plane parallel to the Z-axis, passing through the internal supply flow channel S1a. Figure 13 shows the flow channel of the internal supply flow channel S1a within the flow channel structure 33, and omits the flow channels inside the head unit Hn. Figure 13 shows an example in which the containment space CA is provided so as to be separated from the internal supply flow channel S1a, but the containment space CA may also be provided so as to be separated from the internal supply flow channel S1b.

[0093] As shown in Figure 13, the containment space CA is located upstream of the filter FT. In the example in Figure 13, the containment space CA is defined by closing the opening of a recess RC1 provided on the upper surface SZ11 of the internal supply channel S1a within the flow channel plate Su1 with a weak adhesive portion GLW. In the first embodiment, the containment space CA is provided on the upper surface SZ11 of the internal supply channel S1a, but it may also be provided on the side or bottom surface of the internal supply channel S1a. However, if the containment space CA is provided on the side or bottom surface of the internal supply channel S1a, the spilled material PS will not flow out into the internal supply channel S1a easily. Therefore, by providing the containment space CA on the upper surface SZ11, the spilled material PS can flow out into the internal supply channel S1a more easily compared to the configuration in which the containment space CA is provided on the side or bottom surface of the internal supply channel S1a.

[0094] Preferably, the fragile adhesive portion GLW is provided in such a way that it is intentionally more prone to deterioration than the most easily deteriorated adhesive portion GL among the multiple adhesive portions GL in the liquid spray head 30. The most easily deteriorated adhesive portion GL among the multiple adhesive portions GL in the liquid spray head 30 is the adhesive portion GL that has the shortest distance from the portion defining the flow path SF to the portion of the adhesive portion GL opposite to the end defining the flow path SF in the initial state of the liquid spray head 30, assuming that the ink conditions in contact with the multiple adhesive portions GL in the liquid spray head 30 are the same. Hereinafter, the shortest distance from the portion of the adhesive portion GL or fragile adhesive portion GLW that defines the flow path SF to the portion opposite to the end defining the flow path SF in the initial state of the liquid spray head 30 may be referred to as the "ink penetration distance". In this embodiment, the explanation will proceed assuming that the most easily deteriorated adhesive portion GL is adhesive portion GL57. However, if the condition of the ink in contact with multiple adhesive parts GL within the liquid spray head 30 differs from that of the others, the adhesive part GL that is most susceptible to deterioration may be the one located in a high-flow area within the flow path SF, or it may be the one located in a high-temperature area within the flow path SF. High-temperature areas within the flow path SF include the vicinity of the drive element E, and the vicinity of a heater (not shown) that is provided when using inks that need to be used at high temperatures, such as UV ink.

[0095] In the first embodiment, the fragile adhesive portion GLW is an example of a "first adhesive portion," the adhesive portion GL57 is an example of a "second adhesive portion," the flow path plate Su5 is an example of a "first flow path member," and the case 335 is an example of a "second flow path member." The internal supply flow path S1a configured within the flow path plate Su5 is an example of a "first flow path," and the internal supply flow path R1a configured within the case 335 is an example of a "second flow path." However, the pair of "first flow path member" and "second flow path member" is not limited to the pair of flow path plate Su5 and case 335, but may be any two members that constitute the liquid injection head 30, which form part of the flow path SF and are bonded together with some kind of adhesive. Specifically, the pair of two flow path members may be a pair of two adjacent flow path plates Su within the flow path structure 33, and a pair of two members that constitute the head unit Hn, which form part of the flow path SF and are bonded together with some kind of adhesive. The pairs of components within the head unit Hn are, specifically, the pair of case 335 and communication plate 42, the pair of communication plate 42 and pressure chamber substrate 43, the pair of communication plate 42 and compliance substrate 45, the pair of communication plate 42 and nozzle plate 40, and the pair of pressure chamber substrate 43 and diaphragm 44.

[0096] There are two embodiments of intentionally making the fragile adhesive portion GLW more prone to deterioration than the adhesive portion GL57, as described below. In the first embodiment of the fragile adhesive portion GLW, the adhesive forming the fragile adhesive portion GLW and the adhesive forming the adhesive portion GL57 are of the same type, and the ink penetration distance LGW of the fragile adhesive portion GLW is shorter than the ink penetration distance L57 of the adhesive portion GL57 shown in Figures 7 and 13. The ink penetration distance LGW is the length of the fragile adhesive portion GLW in the direction along the Z axis in the initial state of the liquid spray head 30. In other words, the ink penetration distance LGW is the shortest distance from the end face in the Z2 direction where the fragile adhesive portion GLW defines the supply channel S1a within the structure to the end face in the Z1 direction where the fragile adhesive portion GLW defines the containment space CA. The ink penetration distance L57 is the length of the adhesive portion GL57 in the direction perpendicular to the Z axis in the initial state of the liquid spray head 30. In other words, as shown in Figure 7, the ink penetration distance L57 is the shortest distance from the end face in the X1 direction that defines the internal supply channel S1a of the structure to the end face opposite to the end face in the X1 direction that defines the internal supply channel S1a of the structure.

[0097] In a second embodiment of the fragile adhesive section GLW, the liquid resistance of the fragile adhesive section GLW is lower than that of the adhesive section GL57. However, it is preferable that the liquid resistance of the fragile adhesive section GLW is slightly lower than that of the adhesive section GL57. For example, by changing the ratio of the main component to the hardener in the fragile adhesive section GLW compared to the ratio of the main component to the hardener in the adhesive section GL57, it is possible to create a fragile adhesive section GLW with slightly reduced liquid resistance. Alternatively, at the time of manufacturing the liquid spray head 30, it is possible to apply heat locally to the fragile adhesive section GLW using a laser or the like to partially advance the curing reaction, thereby lowering the final degree of curing of the fragile adhesive section GLW.

[0098] The discharge material PS contains powder that is too small to pass through the opening of the filter FT. For example, the discharge material PS is a granular material which is an aggregate of powder. This powder is, for example, a pellet formed from an adhesive having a filler of 10 μm or more. Alternatively, the discharge material PS may be a liquid containing powder that is too small to pass through the opening of the filter FT. Alternatively, if the type of ink flowing through the internal supply channel S1a is known at the time of manufacturing the liquid spray head 30, the discharge material PS may be an aggregate of powder that is too small to pass through the opening of the filter FT and a substance that dissolves in the ink flowing through the internal supply channel S1a. In order to prevent foreign matter from passing through the opening of the filter FT and clogging the nozzle Nz, it is preferable that the opening of the filter FT is smaller than the opening of the nozzle Nz. In this case, by making the powder of the discharge material PS too small to pass through the opening of the nozzle Nz, it becomes easier to block the opening of the filter FT with the powder of the discharge material PS.

[0099] Furthermore, the amount of discharge material PS should be such that it clogs the filter FT. In this specification, the amount that clogs the filter FT means the amount of discharge material PS that flows into the supply channel S1a within the structure, causing a significant decrease in the flow rate value measured by the flow meter 29.

[0100] 1-9. Function and Operation of the First Embodiment Figure 14 is a diagram showing the functions of the inkjet system SYS. Figure 15 is a flowchart showing the operation of the inkjet system SYS. The control circuit 21 functions as an acquisition unit 71, an estimation unit 73, and a notification unit 75 by executing the read control program PM2.

[0101] The series of processes shown in Figure 15 are performed periodically. For example, the inkjet system SYS performs the series of processes shown in Figure 15 daily, weekly, or monthly. However, the series of processes shown in Figure 15 may be performed irregularly. For example, when the inkjet system SYS receives image data Img from the processing unit 200, it may perform the series of processes shown in Figure 15 before the printing process, or it may perform the series of processes shown in Figure 15 at the instruction of user U.

[0102] In step SC2, the control circuit 21 transmits the request signal RI to the flow meter 29. After the processing of step SC2 is completed, the control circuit 21 waits for a response from the flow meter 29.

[0103] When the flow meter 29 receives the request signal RI, the flow meter 29 measures the flow rate in the flow path SF in step SQ2. Then, in step SQ4, the flow meter 29 transmits flow information QI, which indicates the measured flow rate value, to the control circuit 21. After the processing in step SQ4 is completed, the flow meter 29 terminates the series of processes shown in Figure 15.

[0104] In step SC4, the control circuit 21 functions as an acquisition unit 71 to acquire flow rate information QI from the flow meter 29. Next, in step SC6, the control circuit 21 functions as an estimation unit 73 to estimate the degree of deterioration of the adhesive part GL57 by determining whether or not the filter FT is clogged based on the flow rate information QI. Specifically, the estimation unit 73 stores the flow rate information QI acquired by the acquisition unit 71 in the memory circuit 22. For the sake of simplicity, the previously stored flow rate value stored in the memory circuit 22 may be referred to as the "previous flow rate value," and the flow rate value included in the flow rate information QI acquired by the acquisition unit 71 may be referred to as the "current flow rate value." The estimation unit 73 determines whether the current flow rate value is less than the previous flow rate value minus a predetermined value. If the current flow rate value is greater than or equal to the previous flow rate value minus a predetermined value, the estimation unit 73 estimates that the filter FT is not clogged and therefore the adhesive part GL57 is not deteriorated. On the other hand, if the current flow rate is less than the previous flow rate minus a predetermined value, the estimation unit 73 estimates that the filter FT is clogged and therefore the adhesive part GL57 is deteriorating. The predetermined value is a value based on the flow rate that decreases when the spilled material PS flows into the supply channel S1a within the structure. The predetermined value is stored in the memory circuit 22 in advance by the head maker based on experiments or experience.

[0105] After the processing in step SC6 is completed, in step SC8, the control circuit 21 determines, based on the estimation result, whether or not the user U should be notified. More specifically, if there is a liquid spray head 30 in which the adhesive portion GL57 is estimated to be deteriorated, the control circuit 21 determines that the user U should be notified.

[0106] If the determination result in step SC8 is positive, the control circuit 21 functions as a notification unit 75 in step SC10 to generate notification information CI based on the estimation result and notifies the user U of the generated notification information CI. Specifically, the control circuit 21 transmits the notification information CI to the processing unit 200, causing the processing unit 200 to notify the user U of the notification information CI. The notification information CI is information that prompts the replacement of the liquid spray head 30 which shows signs of ink leakage. For example, let's assume that the estimation result is that the adhesive part GL57 is deteriorated, that is, that there are signs of ink leakage from the liquid spray head 30. Under this premise, the notification information CI is a string of characters that reads, "There are signs that the liquid spray head is malfunctioning. There are signs that ink is leaking from this liquid spray head. Please replace the liquid spray head." However, the notification information CI is not limited to a string of characters. For example, the notification information CI may be information showing an image in which an enhanced image is superimposed on an image showing the head module 3, highlighting the liquid spray head 30 that shows signs of ink leakage. The enhanced image may be, for example, an image in which the color of the liquid spray head 30 showing signs of ink leakage is different from the color of the liquid spray head 30 that does not show signs of ink leakage, or an image with a callout pointing to the liquid spray head 30 showing signs of ink leakage, with the text "We recommend replacing this liquid spray head." inside the callout.

[0107] Furthermore, the estimation unit 73 may estimate the lifespan of the liquid spray head 30 based on the degree of deterioration of the adhesive portion GL57 and the period from the date the liquid spray head 30 was put into use to the current date. For example, the memory circuit 22 stores information indicating the date the liquid spray head 30 was put into use, information indicating the first period from the start of use of the liquid spray head 30 until ink leaks from the fragile adhesive portion GLW, obtained by experiments conducted by the head manufacturer, etc., and information indicating the second period from the start of use of the liquid spray head 30 until ink leaks from the adhesive portion GL57. It is assumed that ink leakage from the fragile adhesive portion GLW has been detected. The estimation unit 73 calculates the lifespan of the liquid spray head 30 using the following formula (1). Lifespan of liquid spray head 30 = (Current date - Date when liquid spray head 30 was first used) × (Second period / First period) + Current date (1)

[0108] The notification unit 75 includes lifespan information, which is estimated by the estimation unit 73, in the notification information CI and notifies the user U. The lifespan information is, for example, a string of characters such as, "The expected date on which the liquid spray head 30 will fail is yyyy / mm / dd." where yyyy is a four-digit number, mm is an integer from 1 to 12, and dd is an integer from 1 to 31. The notification unit 75 may also notify the user U of the notification information CI when it detects that ink has leaked from the fragile adhesive part GLW, or it may notify the user of the notification information CI a predetermined number of days before the date indicated in the lifespan information.

[0109] After the processing in step SC10 is completed, the control circuit 21 terminates the series of processes shown in Figure 15. Also, if the determination result in step SC8 is negative, the control circuit 21 terminates the series of processes shown in Figure 15.

[0110] When the processing unit 200 receives notification information CI, the control circuit 210 of the processing unit 200 notifies the user U of the notification information CI in step SS2. Specifically, the control circuit 210 causes the display device 270 to display the string or image indicated by the notification information CI.

[0111] In Figures 14 and 15, the control circuit 21 functions as the estimation unit 73 and the notification unit 75, but this is not limited to this configuration. For example, the control circuit 21 may transmit flow rate information QI to the processing unit 200, and the control circuit 210 of the processing unit 200 may function as the estimation unit 73 and the notification unit 75.

[0112] 1-10. Summary of the First Embodiment In the following, the first embodiment will be summarized using an example in which the flow path SF corresponds to the "flow path", the internal supply flow path S1a corresponds to the "first flow path", the internal supply flow path R1a corresponds to the "second flow path", the flow path plate Su5 corresponds to the "first flow path member", the case 335 corresponds to the "second flow path member", the fragile adhesive part GLW corresponds to the "first adhesive part", and the adhesive part GL57 corresponds to the "second adhesive part".

[0113] The liquid spray head 30 includes a flow path SF that communicates with a nozzle Nz for spraying ink, a containment space CA, a fragile adhesive portion GLW that separates the flow path SF and the containment space CA, and an outflow material PS that is contained within the containment space CA and flows into the fragile adhesive portion GLW when the fragile adhesive portion GLW can no longer separate the flow path SF and the containment space CA. According to the first embodiment, the fragile adhesive portion GLW deteriorates due to contact with the liquid, causing the spill material PS to flow into the flow channel SF. Therefore, the user U can know that the adhesive portion GL for the flow channel seal has deteriorated. The user U can know the point at which deterioration of the adhesive portion GL for the flow channel seal is detected as an appropriate time to replace the liquid spray head 30.

[0114] Furthermore, in a first embodiment of the fragile adhesive portion GLW, the liquid injection head 30 further comprises a flow path plate Su5 that constitutes an internal supply flow path S1a which is part of the flow path SF, a case 335 that constitutes an internal supply flow path R1a which is part of the flow path SF, and an adhesive portion GL57 that adheres the flow path plate Su5 and the case 335 so as to create a liquid-tight communication between the internal supply flow path S1a and the internal supply flow path R1a, and the fragile adhesive portion GLW and the adhesive portion GL57 are formed of the same type of adhesive. According to the first embodiment, since the adhesive forming the fragile adhesive portion GLW and the adhesive forming the adhesive portion GL57 are of the same type, the same degradation conditions can be applied to the fragile adhesive portion GLW and the adhesive portion GL57 for various inks. As a result of being able to apply the same degradation conditions, according to the first embodiment, the rate of degradation of the fragile adhesive portion GLW and the adhesive portion GL57 when in contact with ink can be made closer compared to the embodiment in which the adhesives are of different types, and the accuracy of estimating the degree of degradation of the adhesive portion GL57 can be improved.

[0115] Furthermore, in the first embodiment of the fragile adhesive portion GLW, the ink penetration distance LGW, which is the shortest distance from the portion defining the flow path SF to the portion defining the containment space CA in the fragile adhesive portion GLW, is shorter than the ink penetration distance L57, which is the shortest distance from the portion defining the flow path SF to the end of the adhesive portion GL57 opposite to the portion defining the flow path. According to the first embodiment, compared to an embodiment in which the ink penetration distance LGW is longer than the ink penetration distance L57, it is possible to detect signs of ink leakage from the adhesive portion GL57 before the point in time when ink actually leaks from the adhesive portion GL57.

[0116] Furthermore, in a second embodiment of the weak adhesive portion GLW, the liquid resistance of the weak adhesive portion GLW is lower than that of the adhesive portion GL57. According to the first embodiment, signs of ink leakage from the adhesive portion GL57 can be detected before ink actually leaks from the adhesive portion GL57.

[0117] Furthermore, the liquid injection head 30 is equipped with a filter FT located downstream of the containment space CA in the flow path SF, and the discharge material PS contains powder that is too small to pass through the opening of the filter FT. According to the first embodiment, the degree of deterioration of the adhesive portion GL57 can be estimated using the flow meter 29, based on the fact that the filter FT has become clogged and the flow resistance has increased.

[0118] Furthermore, the control circuit 21 of the inkjet printer 100 functions as an acquisition unit 71 that acquires flow rate information QI, which is information regarding whether or not the filter FT is clogged with the outflow material PS, and an estimation unit 73 that estimates the degree of deterioration of the adhesive part GL57 based on the flow rate information QI acquired by the acquisition unit 71. According to the first embodiment, the degree of deterioration of the adhesive portion GL57 can be estimated based on the flow rate information QI. Furthermore, according to this embodiment, signs of ink leakage from the liquid spray head 30 can be detected without damaging the liquid spray head 30.

[0119] Furthermore, the control circuit 21 also functions as a notification unit 75 that prompts the replacement of the liquid spray head 30 when the estimation unit 73 estimates that the adhesive portion GL57 is deteriorating. According to the first embodiment, user U can replace the liquid spray head 30 before ink leaks from it by replacing the liquid spray head 30 in accordance with the instruction to replace the liquid spray head 30.

[0120] In the first embodiment, the inkjet printer 100 had a flow meter 29, but it may have a pressure gauge instead of the flow meter 29. A pressure gauge can also detect changes in flow resistance.

[0121] The amount of discharge material PS may be an amount that can clog the filter FT. An amount that can clog the filter FT is an amount that is greater than the amount that clogs the filter FT, and when the discharge material PS flows into the internal supply channel S1a of the structure, a predetermined percentage or more of the nozzles Nz that communicate with the internal supply channel S1a of the structure will experience spray failure. The predetermined percentage is a value set by the head manufacturer through experimentation or experience. If the amount of leaked material PS is such that it can clog the filter FT, the change in flow resistance becomes large, making it easier to estimate the degree of deterioration of the adhesive part GL57 by measuring the flow rate with the flow meter 29. Since a predetermined percentage or more of the nozzles Nz that communicate with the supply flow path S1a within the structure will experience a spray failure, even if the flow meter 29 does not measure the flow rate of the flow path SF, the user U may know that ink is leaking from the liquid spray head 30 by checking the image formed on the medium PP. In other words, if the amount of leaked material PS is such that it can clog the filter FT, the control circuit 21 of the inkjet printer 100 does not need to function as the acquisition unit 71, estimation unit 73, and notification unit 75. For example, if the quality of the image formed on the medium PP is unacceptable to the user U, the user U will replace the liquid spray head 30. Furthermore, user U can limit the use of the liquid jet head 30 until it is replaced if it shows signs of ink leakage, thus preventing contamination inside the liquid jet head 30 or failure of electronic components if it is used continuously. This allows the head manufacturer to collect the liquid jet head 30 before its electrical components fail, and then use the collected liquid jet head 30 to manufacture refurbished liquid jet heads 30. Since the head manufacturer can manufacture refurbished liquid jet heads 30 using collected liquid jet heads 30 at a lower cost than new liquid jet heads 30, they can offer the refurbished liquid jet heads 30 to printer manufacturers and user U at a lower cost.

[0122] 2. Second Embodiment In the first embodiment, the degree of deterioration of the adhesive portion GL57 was estimated by detecting a sharp increase in the flow resistance of the flow channel SF when the spilled material PS flowed into the flow channel SF, but the embodiment is not limited to this. In the second embodiment, the degree of deterioration of the adhesive portion GL57 is estimated by detecting an abnormality in the color of the image formed on the medium PP when the spilled material PS flowed into the flow channel SF. The second embodiment will be described below.

[0123] 2-1. Overview of the Second Embodiment Figure 16 is a block diagram showing an example configuration of the inkjet printer 100a in the second embodiment. The inkjet printer 100a has a liquid jet head 30a instead of a liquid jet head 30, a control circuit 21a instead of a control circuit 21, a memory circuit 22a instead of a memory circuit 22, and an imaging device 80 instead of a flow meter 29. The liquid jet head 30a is provided with a containment space CAa instead of a containment space CA, and the discharge material PSa is contained within the containment space CAa instead of the discharge material PS.

[0124] The spill material PSa has the following two embodiments. In the first embodiment of the spill material PSa, the spill material PSa contains a colorant comprising at least one of a dye and a pigment. For example, the spill material PSa may be an ink comprising at least one of a dye and a pigment, or it may be a powder aggregate comprising at least one of a dye and a pigment. The color of the colorant contained in the spill material PSa is preferably different from the color of the ink flowing through the channel SF, from the viewpoint that the color of the image formed on the medium PP when the spill material PS flows into the channel SF is abnormal. However, since the color of the ink flowing through the channel SF is determined by the user U, the color of the ink flowing through the channel SF may be unknown at the time of manufacturing of the liquid spray head 30a. Therefore, for example, the color of the colorant contained in the spill material PSa is preferably a color that is not commonly used as an ink color. Colors that are not commonly used as an ink color include, for example, colors other than cyan, magenta, yellow, and black.

[0125] Furthermore, in the first embodiment of the spill material PSa, the spill material PSa may contain at least one of a dye and a pigment, and may contain two or more colorants of different colors. In this specification, "different colors" means that if any two of the two or more colorants are chromatic, one or more of the hue, saturation, and lightness are different, and the color difference ΔE is 13 or more. Also, if any two of the colorants are achromatic, it means that the lightness is different and the color difference ΔE is 13 or more. Furthermore, "containing two or more colorants in the spill material PSa" means that one spill material PSa may contain two or more colorants, or one containment space CAa may contain spill material PSa containing a colorant of one color and spill material PSa containing a colorant of a different color. Alternatively, the liquid spray head 30a may be provided with two or more containment spaces CAa, and each of these two or more containment spaces CAa may contain spill material PSa containing colorants of different colors.

[0126] In a second embodiment of the spill material PSa, the spill material PSa includes a phosphor that emits light in response to ultraviolet light when irradiated with ultraviolet light. For example, the phosphor is a fluorescent pigment such as strontium sulfide or strontium aluminate. The phosphor emits light such as blue, yellow, or red in response to ultraviolet light. Since it is preferable that the phosphor is not visible to the user U under visible light, it is preferable that it be colorless, transparent, or white.

[0127] The containment space CAa may be located at any point in the flow path SF. Specifically, the containment space CAa may be located either upstream or downstream of the filter FT. Alternatively, the containment space CAa may be located in the in-head supply flow path R1a.

[0128] The imaging device 80 captures an image formed on the medium PP. The imaging device 80 includes an imaging optical system and an image sensor. The imaging optical system is an optical system that includes at least one imaging lens and may include various optical elements such as prisms, as well as zoom lenses and focus lenses. From the viewpoint of facilitating imaging of the detection surface with the image sensor, the imaging optical system is preferably configured to include a wide-angle lens or a fisheye lens. The image sensor is composed of, for example, a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary MOS) image sensor. When the image sensor receives a request signal RI from the control circuit 21a, it captures an image via the imaging optical system and transmits image information GI indicating the captured image to the control circuit 21a.

[0129] Furthermore, in a second embodiment of the spilled material PSa, the imaging device 80 has a light source capable of irradiating ultraviolet light.

[0130] The memory circuit 22a differs from the memory circuit 22 in that it stores the control program PM2a instead of the control program PM2. As shown in Figure 16, the control circuit 21a functions as the acquisition unit 71a, the estimation unit 73a, and the notification unit 75 by executing the read control program PM2a.

[0131] 2-2. Operation of the second embodiment Figure 17 is a flowchart showing the operation of the inkjet system SYS in the second embodiment. Only the differences from Figure 15 will be explained below.

[0132] In step SC1, the control circuit 21a performs a printing process for checking for signs of leakage. This printing process involves forming a pattern image on the PP medium that shows a predetermined test pattern. Information indicating the pattern image is stored in advance in the memory circuit 22a. The pattern image includes dots formed by ink being ejected from the liquid ejection head 30a.

[0133] After the processing of step SC1 is completed, in step SC2a, the control circuit 21a transmits the request signal RI to the imaging device 80. After the processing of step SC2a is completed, the control circuit 21a waits for a response from the imaging device 80.

[0134] When the imaging device 80 receives a request signal RI, in step SK2, the imaging device 80 captures a pattern image formed on the medium PP by the ink being ejected from the liquid spray head 30b. In a second embodiment of the spill material PSa, the imaging device 80 captures a pattern image formed on the medium PP while irradiating it with ultraviolet light from a light source. Hereinafter, the pattern image in step SK2 may be referred to as the "comparison image". Then, in step SK4, the imaging device 80 transmits image information GI, which indicates the comparison image formed on the medium PP, to the control circuit 21a. After the completion of the processing in step SK4, the imaging device 80 terminates the series of processes shown in Figure 17. The image information GI is information regarding whether or not the color of the liquid flowing in the channel SF is abnormal.

[0135] In step SC4a, the control circuit 21a functions as an acquisition unit 71a to acquire image information GI from the imaging device 80. Next, in step SC6a, the control circuit 21a functions as an estimation unit 73a to estimate the degree of deterioration of the adhesive part GL57 based on the image information GI, depending on whether the color of the liquid flowing in the flow path SF is abnormal or not. Specifically, when the liquid spray head 30a is put into use, a printing process for checking for signs of leakage is performed, and image information showing the image formed on the medium PP is stored in the storage circuit 22a. Hereinafter, the image shown in the image information stored in the storage circuit 22a when the liquid spray head 30a is put into use may be referred to as the "initial image". The estimation unit 73a compares the color of the dots formed by the ink sprayed from the liquid spray head 30a in the initial image with the color of the dots formed by the ink sprayed from the liquid spray head 30a in the comparison image. If the estimation unit 73a determines that the two colors are the same, it estimates that the color of the liquid flowing in the channel SF is normal and that the adhesive part GL57 is not deteriorated. On the other hand, if the estimation unit 73a determines that the two colors are different, it estimates that the color of the liquid flowing in the channel SF is abnormal and that the adhesive part GL57 is deteriorated.

[0136] 2-3. Summary of the Second Embodiment As described above, in the first embodiment of the spill material PSa, the spill material PSa in the second embodiment includes a colorant containing at least one of a dye and a pigment. According to the second embodiment, it is possible to detect whether or not the adhesive portion GL57 is deteriorating based on the color abnormality of the image formed on the medium PP.

[0137] Furthermore, in the first embodiment of the spill material PSa, the spill material PSa may contain two or more colorants of different colors. As described above, at the time of manufacturing the liquid spray head 30a, the color of the ink flowing through the channel SF may be unknown. Therefore, in the embodiment where the spill material PSa is a single colorant, the color of the colorant contained in the spill material PSa may be the same as the color of the ink flowing in the channel SF. If the color of the colorant contained in the spill material PSa and the color of the ink flowing in the channel SF are the same, the color of the image formed on the medium PP when the spill material PSa flows into the channel SF may not change, and there is a risk that the collapse of the fragile adhesive part GLW may not be detected. Therefore, by containing two or more colorants of different colors, the spill material PSa has a colorant of a different color from the color of the ink in the channel SF, so that regardless of the color of the ink in the channel SF, the color of the image formed on the medium PP when the spill material PSa flows into the channel SF can be changed. Accordingly, according to the second embodiment of the spill material PSa, user U can use the same type of liquid spray head 30a for various inks.

[0138] Furthermore, in a second embodiment of the spill material PSa, the spill material PSa includes a phosphor that emits light in response to ultraviolet light when irradiated with ultraviolet light. In either the first or second embodiment of the leak material PSa, when the leak material PSa flows into the channel SF, a portion of the ink ejected from the nozzle Nz is replaced by the colorant or phosphor of the leak material PSa, resulting in a decrease in the quality of the image formed on the medium PP compared to a state where the leak material PSa does not flow into the channel SF. However, in the first embodiment of the leak material PSa, the colorant of the leak material PSa included in the image formed on the medium PP is easily noticeable to the user U, whereas in the second embodiment of the leak material PSa, the phosphor is not noticeable under visible light, so the phosphor included in the image formed on the medium PP is less likely to be noticed by the user U. Therefore, according to the second embodiment of the leak material PSa, compared to the first embodiment of the leak material PSa, it is less likely for the user U to notice the decrease in the quality of the image formed on the medium PP even when the leak material PSa flows into the channel SF.

[0139] Furthermore, the control circuit 21a of the inkjet printer 100 functions as an acquisition unit 71a that acquires image information GI, which is information regarding whether or not the color of the liquid flowing in the channel SF is abnormal, and an estimation unit 73a that estimates the degree of deterioration of the adhesive part GL57 based on the image information GI acquired by the acquisition unit 71a. According to the second embodiment, the degree of deterioration of the adhesive portion GL57 can be estimated by acquiring image information GI.

[0140] Furthermore, the control circuit 21a also functions as a notification unit 75 that prompts the replacement of the liquid spray head 30a when the estimation unit 73a estimates that the adhesive portion GL57 is deteriorating. User U can replace the liquid spray head 30 before ink leaks from it by replacing the liquid spray head 30 in accordance with the instructions to replace the liquid spray head 30.

[0141] In the second embodiment, the imaging device 80 captures an image formed on the medium PP, but is not limited to this. For example, the imaging device 80 may capture an image of waste liquid in a waste liquid tank (not shown). The waste liquid tank is used for cleaning to recover from spraying abnormalities of the liquid spray head 30. The fragile adhesive portion GLW may rupture during the cleaning process, and the colorant contained in the spill material PSa may be discharged into the waste liquid tank. Therefore, the imaging device 80 captures an image of the waste liquid in the waste liquid tank and transmits image information showing the captured image to the control circuit 21a. The control circuit 21a may use the image information showing the image captured inside the waste liquid tank to estimate the degree of deterioration of the adhesive portion GL57. To improve the accuracy of estimating the degree of deterioration of the adhesive portion GL57, it is preferable for the imaging device 80 to capture both the image formed on the medium PP and the waste liquid in the waste liquid tank. For example, the inkjet printer 100a may have an imaging device 80 for capturing an image formed on the medium PP and an imaging device 80 for capturing the waste liquid in the waste liquid tank, or the imaging device 80 may be movably installed to capture the image formed on the medium PP and the waste liquid in the waste liquid tank.

[0142] In the second embodiment, user U may determine whether there are signs of ink leakage from the liquid spray head 30a by observing at least one of the image formed on the medium PP and the waste liquid in the waste liquid tank. In the second embodiment of the leak material PSa, user U can determine whether there are signs of ink leakage from the liquid spray head 30 by irradiating the image formed on the medium with ultraviolet light using an ultraviolet irradiation device. In the embodiment in which user U determines whether there are signs of ink leakage from the liquid spray head 30 by observing at least one of the image formed on the medium PP and the waste liquid in the waste liquid tank, the inkjet printer 100a does not have an imaging device 80, and the control circuit 21a does not have to function as an acquisition unit 71, an estimation unit 73, and a notification unit 75.

[0143] 3. Third Embodiment In the first embodiment, the spill material PS was contained within the containment space CA, but the spill material PS may also be contained within the fragile adhesive portion GLW located in the flow channel SF. For ease of understanding, the fragile adhesive portion GLW containing the spill material PS may be referred to as the spill material-containing adhesive portion GLP. The third embodiment will be described below.

[0144] Figure 18 is a block diagram showing an example configuration of the inkjet printer 100b in the third embodiment. The inkjet printer 100b has a liquid jet head 30b instead of the liquid jet head 30. The liquid jet head 30b has an adhesive portion GLP containing the spill material PS in the first embodiment instead of the containment space CA. The liquid jet head 30b will be explained using Figure 19.

[0145] Figure 19 is a diagram illustrating the spill material-containing adhesive GLP. The liquid injection head 30b has a flow path plate Su1b instead of a flow path plate Su1. A recess RC1b provided on the upper surface SZ11 of the internal supply flow path S1a within the flow path plate Su1b is filled with the spill material-containing adhesive GLP. The spill material-containing adhesive GLP is positioned so as not to create a liquid-tight connection between the respective flow paths of the two stacked flow path members; in other words, the spill material-containing adhesive GLP does not have the function of sealing the flow path. That is, the spill material-containing adhesive GLP is not bonded across multiple flow path members, but may be bonded only to one flow path member, the flow path plate Su1b. The spill material-containing adhesive GLP is intentionally weaker than the adhesive GL. The spill material-containing adhesive GLP has a first layer GW1 containing the spill material PS and a second layer GW2 not containing the spill material PS. For example, the head manufacturer fills the recess RC1b with an adhesive containing the exudate agent PS to form the first layer GW1, and after the first layer GW1 has hardened, fills the recess RC1b with an adhesive that does not contain the exudate agent PS to form the second layer GW2. In the initial state of the liquid spray head 30b, the Z2 direction surface of the second layer GW2 is in contact with the ink. Note that the exudate agent-containing adhesive part GLP is an example of the "third adhesive part".

[0146] In the third embodiment, as in the first and second embodiments, the leak agent PS mixed in the leak agent-containing adhesive part GLP must flow into the flow channel SF before ink leaks from the adhesive part GL57. There are two embodiments of the leak agent-containing adhesive part GLP that allow the leak agent PS mixed in the leak agent-containing adhesive part GLP to flow into the flow channel SF before ink leaks from the adhesive part GL57. In the first embodiment of the leak agent-containing adhesive part GLP, the adhesive forming the leak agent-containing adhesive part GLP and the adhesive forming the adhesive part GL57 are of the same type, and the thickness LGWb of the second layer GW2 is shorter than the ink penetration distance L57 of the adhesive part GL57. The thickness LGWb is the shortest distance from the end face in the Z2 direction of the leak agent-containing adhesive part GLP defining the supply flow channel S1a within the structure to the end face in the Z2 direction of the first layer GW1.

[0147] In a second embodiment of the GLP adhesive containing the spill-proofing agent, the liquid resistance of the GLP adhesive containing the spill-proofing agent is lower than that of the GL57 adhesive. However, it is preferable that the liquid resistance of the GLP adhesive containing the spill-proofing agent is slightly lower than that of the GL57 adhesive.

[0148] Furthermore, similar to the first embodiment, the flow path SF is equipped with a filter FT located downstream of the adhesive portion GLP containing the spillage material. The amount of spillage material PS mixed into the adhesive portion GLP containing the spillage material may be an amount that clogs the filter FT, or an amount that can completely block the filter FT.

[0149] Furthermore, the control circuit 21 of the inkjet printer 100b functions as an acquisition unit 71 that acquires flow rate information QI, which is information regarding whether or not the filter FT is clogged with spilled material PS, and an estimation unit 73 that estimates the degree of deterioration of the adhesive part GL57 based on the flow rate information QI acquired by the acquisition unit 71. In addition, the control circuit 21 of the inkjet printer 100b may also function as an notification unit 75 that notifies the user to replace the liquid spray head 30 if the estimation unit 73 estimates that the adhesive part GL57 is deteriorated.

[0150] As described above, the liquid spray head 30b in the third embodiment comprises a flow channel SF communicating with a nozzle Nz that sprays ink, and an adhesive part GLP containing an outflow material disposed within the flow channel SF, wherein the adhesive part GLP containing an outflow material includes an outflow material PS that flows into the flow channel SF when the adhesive part GLP containing an outflow material dissolves into the ink in the flow channel SF. According to the third embodiment, the adhesive portion GLP containing the spillage material deteriorates due to contact with the liquid, causing the spillage material PS to flow into the flow path SF. As a result, the user U can know that the adhesive portion GL for sealing the flow path has deteriorated. The user U can know the point at which deterioration of the adhesive portion GL for sealing the flow path is detected as an appropriate time to replace the liquid injection head 30b.

[0151] 4. Variations Each of the embodiments exemplified above can be modified in various ways. Specific examples of modifications that can be applied to each of the embodiments described above are given below. Two or more embodiments arbitrarily selected from the following examples can be merged as appropriate, provided they do not contradict each other.

[0152] 4-1. First variation In the third embodiment, the discharge material-containing adhesive portion GLP was provided in a recess RC1b provided on the upper surface SZ11 of the supply channel S1a within the structure in the flow channel plate Su1b, but is not limited to this. For example, the discharge material-containing adhesive portion GLP may be in the filter chamber Fa and placed on the filter FT.

[0153] Figure 20 is a diagram illustrating the GLPc containing the spill material in the first modified example. The liquid spray head 30c has the GLPc containing the spill material within the filter chamber Fa.

[0154] The leak material-containing adhesive section GLPc is located in the filter chamber Fa and is placed on the filter FT. Furthermore, the leak material-containing adhesive section GLPc does not have a layer in which the leak material PS is not mixed. In the first modified example, the estimation unit 73 should estimate that the adhesive section GL57 is deteriorating when the flow rate value indicated by the flow rate information QI reaches the flow rate value that would occur if all of the leak material PS contained in the leak material-containing adhesive section GLPc flowed into the flow path SF.

[0155] 4-2. Second variation In the third embodiment, the liquid spray head 30b, and in the first modified example, the liquid spray head 30c, have an adhesive GLP containing the spill material PS as in the first embodiment, but they may also have an adhesive GLP containing the spill material PSa as in the second embodiment.

[0156] Figure 21 is a block diagram showing an example configuration of the inkjet printer 100d in a second modified example. The inkjet printer 100d has a liquid jet head 30d instead of a liquid jet head 30a. The liquid jet head 30d has a liquid jet material containing adhesive portion GLPd which includes liquid jet material PSa instead of liquid jet material PS.

[0157] The GLPd adhesive section containing the runoff material has a first layer GW1d instead of the first layer GW1. The first layer GW1d contains runoff material PSa instead of runoff material PS.

[0158] In the second modified example, as in the second embodiment, either the first embodiment of the spill material PSa or the second embodiment of the spill material PSa can be adopted.

[0159] In the example shown in Figure 22, which illustrates the spill material-containing adhesive GLP, the spill material-containing adhesive GLPd is located upstream of the filter FT. However, it is not limited to this, and, as in the second embodiment, the spill material-containing adhesive GLPd may be located at any point in the flow path SF. Specifically, the spill material-containing adhesive GLPd may be located either upstream or downstream of the filter FT.

[0160] Furthermore, the control circuit 21 of the inkjet printer 100d functions as an acquisition unit 71 that acquires image information GI, which is information regarding whether or not the color of the liquid flowing in the channel SF is abnormal, and an estimation unit 73 that estimates the degree of deterioration of the adhesive part GL57 based on the image information GI acquired by the acquisition unit 71. In addition, the control circuit 21 of the inkjet printer 100d may also function as an notification unit 75 that notifies the user to replace the liquid spray head 30 if the estimation unit 73 estimates that the adhesive part GL57 is deteriorated.

[0161] 4-3. Third Variation In the first and second embodiments, the containment space CA is defined by closing the opening of the recess RC1 provided on the upper surface SZ11 with the fragile adhesive portion GLW, but is not limited to this. For example, the containment space CA may be a bypass channel that branches off from the channel SF and rejoins the channel SF downstream of the branching point.

[0162] Figure 23 is a diagram illustrating the containment space CAe in the third modified example. Figure 23 shows a cross-section of the supply section Pb1 in the region RG1 shown in Figure 11 within the liquid injection head 30e in the third modified example, when it is fractured with a plane parallel to the XY plane.

[0163] The liquid injection head 30e has a flow path plate Su2e instead of the flow path plate Su2. The containment space CAe is a bypass flow path that joins the supply unit Pb1 at a second connection point CN2, which is different from the first connection point CN1 of the supply unit Pb1. The containment space CAe is defined by blocking the first connection point CN1 and the second connection point CN2 with a fragile adhesive portion GLW.

[0164] 4-4. Fourth variation In the first embodiment, the third embodiment, and the first modification, as well as in the fourth modification in any one of the first embodiment, the third embodiment, and the first modification, the change in the flow resistance of the flow path SF is detected by a flow meter 29 or a pressure gauge, but is not limited to this. For example, if the driving element E is a piezoelectric element, the change in the flow resistance of the flow path SF may also be detected by information indicating residual vibrations that remain in the pressure chamber C after the driving element E has been driven.

[0165] 4-5. Fifth variation In each of the embodiments described above, the liquid spray head 30 may have an outflow material PS corresponding to each of two or more adhesive parts GL. For example, the liquid spray head 30 may have an outflow material PS for detecting signs of ink leakage from the adhesive part GL in the head unit Hn, and an outflow material PS for detecting signs of ink leakage from the adhesive part GL in the flow channel structure 33. In the sixth modified example, the estimation unit 73 estimates the degree of deterioration of the adhesive part GL in the head unit Hn and the degree of deterioration of the adhesive part GL in the flow channel structure 33. In the sixth modified example, the notification unit 75 notifies the user U of a string of characters indicating the location of signs of ink leakage in the liquid spray head 30 as notification information CI. For example, if it is estimated that the adhesive part GL in the flow channel structure 33 has deteriorated, the notification information CI would be, "There are signs of ink leakage in the flow channel structure."

[0166] Furthermore, by providing the liquid spray head 30 with an outlet material PS corresponding to each of two or more adhesive parts GL, the head manufacturer may replace the part showing signs of ink leakage. For example, suppose an outlet material PS is provided corresponding to the adhesive parts GL in the flow path structure 33 within the liquid spray head 30 and the adhesive parts GL in each head unit Hn, and the notification unit 75 notifies the user U that the adhesive part GL in one of the head units Hn is deteriorating. In this case, the head manufacturer can extend the life of the liquid spray head 30 by replacing the head unit Hn in which the deterioration of the adhesive part GL was detected. [Explanation of symbols]

[0167] 3...Head module, 3α...Housing, 21,21a...Control circuit, 22,22a...Memory circuit, 23...Transport mechanism, 24...Movement mechanism, 28...Communication device, 29...Flow meter, 30,30a,30b,30c,30d,30e...Liquid injection head, 31...Cover member, 32...Holder member, 33...Flow channel structure, 40...Nozzle plate, 42...Communication plate, 43...Pressure chamber substrate, 44...Vibrator, 46...Protection unit, 50...Drive circuit, 51...Flexible substrate, 71,71a...Acquisition unit, 73,73a...Estimation unit, 75...Notification unit, 80...Imaging device, 1 00, 100a, 100b, 100d… Inkjet printer, 200… Processing unit, 210… Control circuit, 242… Endless belt, 260… Input device, 270… Display device, 290… Bus, 333… Laminate, 334a, 334b… Protrusion, 335… Case, C… Pressure chamber, CA, CAa, CAe… Housing space, CI… Notification information, CN1… First connection part, CN2… Second connection part, Ca, Cb… Pressure chamber, Com… Drive signal, E, Ea… Drive element, FT… Filter, Fa, Fa_1, Fa_1-Fa_4, Fa_2, Fa_3, F a_4, Fb_1, Fb_2, Fb_3, Fb_4… Filter chamber, GI… Image information, GL, GL12, GL23, GL34, GL45, GL56, GL57… Adhesive parts, GLP, GLPc, GLPd… Adhesive parts containing exudate, GLW… Weak adhesive parts, GW1, GW1d… First layer, GW2… Second layer, H1, H2, H3, H4… Head unit, Img… Image data, L57, LGW… Ink penetration distance, LGWb… Thickness, Nz… Nozzle, PS, PSa… Exudate, QI… Flow rate information, R1a, R1b… In-head supply channel, R2a R2b... Head internal discharge channel, R3a, R3b... First communication channel, R4a, R4b... Second communication channel, RC1, RC1b... Recess, RG1... Region, RI... Request signal, Ra... First liquid storage chamber, Rb... Second liquid storage chamber, Rn... Head internal channel, S1a... In-structure supply channel, S1b... In-structure supply channel, S1b_in... Supply port, S2a... In-structure discharge channel, S2b... In-structure discharge channel, SF... Channel, SZ11... Top surface, Sn... In-structure channel, Su, Su1, Su1b, Su2, Su2e, Su3, Su4, Su5... Channel plate.

Claims

1. A flow path that communicates with a nozzle that sprays liquid, Containment space and A first adhesive portion that separates the flow path and the containment space, A discharge material contained within the containment space, which flows into the flow path when the first adhesive portion can no longer partition the flow path and the containment space, A liquid spray head characterized by having the following features.

2. A first channel member that constitutes a first channel, which is part of the aforementioned channel, A second flow channel member that constitutes a second flow channel, which is part of the aforementioned flow channel, A second bonding portion that bondes the first flow path member and the second flow path member together so as to create a liquid-tight communication between the first flow path member and the second flow path member, Furthermore, The first adhesive portion and the second adhesive portion are formed with the same type of adhesive. The liquid spray head according to feature 1.

3. The shortest distance from the portion of the first adhesive portion defining the flow path to the portion defining the containment space is shorter than the shortest distance from the portion of the second adhesive portion defining the flow path to the end opposite to the portion defining the flow path. The liquid spray head according to feature 2.

4. A first channel member that constitutes a first channel, which is part of the aforementioned channel, A second flow channel member that constitutes a second flow channel, which is part of the aforementioned flow channel, A second bonding portion that bondes the first flow path member and the second flow path member together so as to create a liquid-tight communication between the first flow path member and the second flow path member, Furthermore, The liquid resistance of the first adhesive portion is lower than that of the second adhesive portion. The liquid spray head according to feature 1.

5. The flow path further comprises a filter located downstream of the containment space, The discharge material contains powder that is too small to pass through the opening of the filter. The liquid spray head according to feature 1.

6. The amount of the spilled material contained within the containment space is such that it can block the filter. The liquid spray head according to feature 5.

7. The aforementioned spill material includes a colorant comprising at least one of a dye and a pigment. The liquid spray head according to feature 1.

8. The aforementioned spill material contains two or more colorants of different colors. The liquid spray head according to feature 7.

9. The aforementioned spill material contains a phosphor that reacts to ultraviolet light and emits light when irradiated with ultraviolet light. The liquid spray head according to feature 1.

10. A flow path that communicates with a nozzle that sprays liquid, A third adhesive portion is arranged within the flow path, Equipped with, The third adhesive portion includes a discharge material that flows into the flow path when the third adhesive portion dissolves into the liquid in the flow path. A liquid spray head characterized by the following features.

11. A first channel member that constitutes a first channel, which is part of the aforementioned channel, A second flow channel member that constitutes a second flow channel, which is part of the aforementioned flow channel, A second bonding portion that bondes the first flow path member and the second flow path member together so as to create a liquid-tight communication between the first flow path member and the second flow path member, A liquid spray head according to claim 5 or 6, comprising: An acquisition unit that acquires information regarding whether or not the filter is clogged with the discharged material, Based on the information acquired by the acquisition unit, an estimation unit estimates the degree of deterioration of the second adhesive portion, A liquid injection device characterized by being equipped with the following features.

12. If the estimation unit estimates that the second adhesive portion is deteriorated, the system further includes a notification unit that prompts the replacement of the liquid spray head. The liquid injection device according to feature 11.

13. A first channel member that constitutes a first channel, which is part of the aforementioned channel, A second flow channel member that constitutes a second flow channel, which is part of the aforementioned flow channel, A second bonding portion that bondes the first flow path member and the second flow path member together so as to create a liquid-tight communication between the first flow path member and the second flow path member, A liquid spray head according to claim 7 or 8, comprising: An acquisition unit that acquires information regarding whether or not the color of the liquid flowing in the aforementioned channel is abnormal, Based on the information acquired by the acquisition unit, an estimation unit estimates the degree of deterioration of the second adhesive portion, A liquid injection device characterized by being equipped with the following features.

14. If the estimation unit estimates that the second adhesive portion is deteriorated, the system further includes a notification unit that prompts the replacement of the liquid spray head. The liquid injection device according to feature 13.

Images