Liquid jet head and liquid jet device

Abstract

To provide a liquid jet head which can be disassembled easily to enable reuse of unbroken and non-degraded components which are taken out therefrom, and to provide a liquid jet device.SOLUTION: A liquid jet head includes: a head chip 8 configured to jet a liquid in a +Z direction; and a passage structure disposed in a -Z direction. The head chip 8 has an introduction port 44a and a lead-out port 44b for connecting with a passage in the passage structure in a liquid-tight manner and has an upper surface 40a facing in the -Z direction. The upper surface 40a is provided with a first group of recessed parts 131 which can retain the liquid leaking when a passage connection between the head chip 8 and the passage structure is released; and a liquid non-retention part which does not retain the leaking liquid.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a liquid ejection head and a liquid ejection apparatus that eject liquid from nozzles. [Background technology]

[0002] For example, Patent Document 1 discloses a liquid jet head that includes a plurality of head chips having a nozzle plate with a plurality of nozzles formed therein that jet a liquid such as ink onto a medium such as cloth or paper, and a flow path structure that is connected to the plurality of head chips via flow paths. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-39804 Summary of the Invention [Problem to be solved by the invention]

[0004] When a part of a liquid jet head breaks down or deteriorates, it is desirable to disassemble the liquid jet head, remove the liquid jet head, and reuse the parts of the liquid jet head that are not broken or deteriorated. However, when disassembling the liquid jet head, there is a risk that ink leaking from the flow path connection part between the head chip and the flow path structure will damage the parts to be reused, such as the head chip and the relay board electrically connected to the head chip. [Means for solving the problem]

[0005] An aspect of the present invention that solves the above problem is a liquid ejection head comprising: a head chip that ejects liquid in a first direction; and a flow path structure arranged in a second direction opposite to the first direction, wherein the head chip has a flow path connection portion for liquid-tight connection with a flow path in the flow path structure and has an upper surface facing the second direction, and the upper surface is provided with a first liquid holding portion that can hold liquid that leaks when the flow path connection between the head chip and the flow path structure is released, and a liquid non-holding portion that does not hold the leaked liquid.

[0006] Another aspect of the present invention that solves the above problem is a liquid ejection head comprising a plurality of head chips that eject liquid in a first direction, and a flow path structure arranged in a second direction opposite to the first direction, wherein the flow path structure has a plurality of flow path connection portions for liquid-tight connection with flow paths in the plurality of head chips and has a flow path connection surface facing the first direction, and the flow path connection surface is provided with a fourth liquid holding portion that can hold liquid that leaks when the flow path connection between the head chip and the flow path structure is released, and a liquid non-holding portion that does not hold the leaked liquid.

[0007] Another aspect of the present invention that solves the above problem is a liquid ejection apparatus that includes the liquid ejection head of the above aspect, and a liquid storage section that supplies liquid to the liquid ejection head. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic configuration diagram of a liquid ejecting device according to a first embodiment. [Figure 2] 1 is an exploded perspective view of a liquid jet head according to a first embodiment. [Figure 3] 2 is a cross-sectional view of the liquid jet head according to the first embodiment taken along the line AA. FIG. [Figure 4] 1 is a cross-sectional view of a main part of a liquid jet head according to a first embodiment. [Figure 5] FIG. 2 is an exploded perspective view of the head chip according to the first embodiment. [Figure 6] FIG. 2 is a plan view of a pressure chamber substrate. [Figure 7] FIG. 7 is a cross-sectional view taken along line BB in FIG. 6. [Figure 8] FIG. 2 is a plan view of a head chip according to the first embodiment. [Figure 9] 3 is a cross-sectional view of the liquid jet head according to the first embodiment when the channel connection is released. FIG. [Figure 10] FIG. 10 is a plan view of a head chip according to a first modified example of the first embodiment. [Figure 11] FIG. 10 is a plan view of a head chip according to a second modification of the first embodiment. [Figure 12] FIG. 10 is a plan view of a head chip according to a third modification of the first embodiment. [Figure 13] FIG. 10 is a plan view of a head chip according to a fourth modified example of the first embodiment. [Figure 14] FIG. 10 is a cross-sectional view of a liquid jet head according to a second embodiment. [Figure 15] FIG. 10 is a plan view of a flow path structure according to a second embodiment. [Figure 16] 10 is a cross-sectional view of the liquid jet head according to the second embodiment when the channel connection is released. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present invention will be described in detail below based on embodiments. However, the following description illustrates one aspect of the present invention and can be modified as desired within the scope of the present invention. In each drawing, the same reference numerals indicate the same components, and their description will be omitted as appropriate. In each drawing, X, Y, and Z represent three spatial axes that are orthogonal to each other. In this specification, the directions along these axes are referred to as the X direction, Y direction, and Z direction. In each drawing, the direction indicated by the arrow is the positive (+) direction, and the direction opposite the arrow is the negative (-) direction. The Z direction indicates the vertical direction, the +Z direction indicates a vertically downward direction, and the -Z direction indicates a vertically upward direction. Furthermore, the directions of the three spatial axes, which are not limited to positive and negative directions, will be described as the X-axis direction, the Y-axis direction, and the Z-axis direction.

[0010] (Embodiment 1) FIG. 1 is a diagram showing a schematic configuration of a liquid ejecting apparatus 1 of the present invention.

[0011] As shown in the figure, the liquid ejection device 1 is an inkjet recording device that ejects and impacts ink, a type of liquid, as ink droplets onto a medium S such as printing paper, and prints an image or the like by forming an array of dots on the medium S. The medium S can be made of any material, such as recording paper, resin film, or cloth.

[0012] The liquid ejecting device 1 includes a liquid ejecting head 2, a liquid storage unit 3, a control unit 4, a transport mechanism 5 that feeds the medium S, and a moving mechanism 6.

[0013] The liquid jet head 2 jets ink supplied from a liquid storage unit 3 from a plurality of nozzles onto the medium S. A detailed configuration of the liquid jet head 2 will be described later.

[0014] The liquid storage unit 3 stores the ink to be ejected from the liquid ejection head 2. Examples of the liquid storage unit 3 include a cartridge that is detachable from the liquid ejection device 1, a bag-shaped ink pack made of flexible film, and an ink tank that can be refilled with ink. Although not specifically shown, the liquid storage unit 3 may store, for example, multiple types of ink with different colors, components, etc., individually.

[0015] In this embodiment, the liquid storage unit 3 has a main tank 3a and a sub-tank 3b for each type of ink. The sub-tank 3b is connected to the liquid ejection head 2, and ink consumed by ejecting ink droplets from the liquid ejection head 2 is replenished from the main tank 3a to the sub-tank 3b. Of course, the liquid storage unit 3 may be composed of only the main tank 3a.

[0016] The liquid ejecting device 1 has a circulation mechanism 7 for circulating ink between the liquid ejecting head 2 and the subtank 3b.

[0017] The circulation mechanism 7 includes a supply pump 7a, a circulation pump 7b, a sub-tank 3b, a recovery tube 7c, and a supply tube 7d.

[0018] The supply pump 7a is a pump that supplies the ink stored in the main tank 3a to the sub-tank 3b. The circulation pump 7b is a pump that supplies the ink stored in the sub-tank 3b to the liquid ejection head 2, i.e., pumps the ink under pressure.

[0019] The recovery tube 7c has a flow path for ink that is not used for printing by the liquid jet head 2 and is recovered into the sub-tank 3b. The supply tube 7d has a flow path for ink that is supplied from the sub-tank 3b to the liquid jet head 2.

[0020] The sub-tank 3b is a container that temporarily stores ink. The sub-tank 3b also temporarily stores ink that has not been used for printing by the liquid ejecting head 2 and that has been collected via the collection tube 7c.

[0021] In this circulation mechanism 7, the circulation pump 7b supplies ink from the sub-tank 3b via the supply tube 7d to the liquid jet head 2, and recovers ink not used by the liquid jet head 2 into the sub-tank 3b via the recovery tube 7c. This circulates ink between the liquid jet head 2 and the sub-tank 3b. Furthermore, when the amount of ink stored in the sub-tank 3b falls below a certain amount, the supply pump 7a supplies ink from the main tank 3a to the sub-tank 3b.

[0022] The control unit 4 includes, for example, a control device such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array), and a storage device such as a semiconductor memory. The control unit 4 also includes a power supply device that supplies power from an external power source such as a commercial power source to each element of the liquid ejection device 1. The control unit 4 is electrically connected to the liquid ejection head 2 via external wiring (not shown). The control unit 4 comprehensively controls each element of the liquid ejection device 1 by the control device executing a program stored in the storage device.

[0023] The transport mechanism 5 transports the medium S in the X-axis direction, and includes, for example, a transport roller 5a that is rotated by a transport motor that is driven under the control of the control unit 4.

[0024] The movement mechanism 6 is a mechanism for reciprocating the liquid ejection head 2 in the Y-axis direction, and includes a holder 6a that holds the liquid ejection head 2, and a conveyor belt 6b that is an endless belt that is stretched along the Y-axis direction. The control unit 4 controls the driving of a conveyor motor (not shown) to rotate the conveyor belt 6b, and moves the liquid ejection head 2 reciprocally in the Y-axis direction together with the holder 6a fixed to the conveyor belt 6b.

[0025] The liquid jet head 2 performs a jetting operation of jetting ink supplied from the liquid storage unit 3 as ink droplets in the +Z direction from each of the multiple nozzles 21 (see FIG. 3) under the control of the control unit 4. This jetting operation by the liquid jet head 2 is performed in parallel with the transport of the medium S by the transport mechanism 5 and the reciprocating movement of the liquid jet head 2 by the movement mechanism 6, thereby applying ink to the medium S, or so-called printing.

[0026] Fig. 2 is an exploded perspective view of the liquid jet head 2. Fig. 3 is a cross-sectional view of a main part of the liquid jet head 2 taken along line AA in Fig. 2. Fig. 4 is an enlarged view of the main part of Fig. 3. Note that the directions of the liquid jet head 2 will be described based on the directions when the liquid jet head 2 is mounted on the liquid jet device 1, i.e., the X-axis direction, Y-axis direction, and Z-axis direction.

[0027] As shown in the figure, the liquid jet head 2 includes a plurality of head chips 8, a flow path structure 200 having a supply flow path 400 and a recovery flow path 410, a relay substrate 210, and a cover 220.

[0028] The flow path structure 200 has a supply flow path 400 that supplies ink supplied from the sub-tank 3b to the head chip 8, and a recovery flow path 410 that recovers ink not used in the head chip 8 to the sub-tank 3b.

[0029] The flow path structure 200 includes a first flow path member 201, a second flow path member 202, and a sealing member 203. The first flow path member 201, the sealing member 203, and the second flow path member 202 are stacked in this order in the +Z direction.

[0030] The first flow path member 201 is a member in which a first supply flow path 401 and a first recovery flow path 411 are provided, and in this embodiment, is configured by stacking three members, a first member 201a, a second member 201b, and a third member 201c, in the Z-axis direction. The first flow path member 201 has a supply tube connection portion 204a and a recovery tube connection portion 204b on its surface facing the -Z direction. When there is no need to distinguish between the supply tube connection portion 204a and the recovery tube connection portion 204b, they are referred to as tube connection portion 204. In this embodiment, the tube connection portion 204 has a cylindrical shape that protrudes in the -Z direction on the surface of the first flow path member 201 facing the -Z direction. A supply tube 7d is connected to the supply tube connection portion 204a, and a recovery tube 7c is connected to the recovery tube connection portion 204b. The first supply flow path 401 is provided inside the supply tube connection portion 204a, and the first recovery flow path 411 is provided inside the recovery tube connection portion 204b.

[0031] The first supply flow path 401 and the first recovery flow path 411 are configured as flow paths extending in the Z-axis direction or flow paths extending along the interface between stacked members. A liquid reservoir 401a having a wider inner diameter than other regions is provided midway along the first supply flow path 401, and a filter 401b is provided within the liquid reservoir 401a to capture foreign matter such as dust and air bubbles contained in the ink. In this embodiment, the first flow path member 201 includes four supply tube connecting portions 204a, four recovery tube connecting portions 204b, four independent first supply flow paths 401, and four independent first recovery flow paths 411. The first supply flow path 401 may branch into two or more paths downstream of the filter 401b, for example.

[0032] The second flow path member 202 has second supply flow paths 402 that communicate with each of the first supply flow paths 401, and second recovery flow paths 412 that communicate with each of the first recovery flow paths 411. That is, the second flow path member 202 has four second supply flow paths 402 and four second recovery flow paths 412. The first supply flow paths 401 and the second supply flow paths 402 are liquid-tightly connected via a seal member 203. Similarly, the first recovery flow path 411 and the second recovery flow path 412 are liquid-tightly connected via the seal member 203. The seal member 203 is liquid-resistant to liquids such as ink used in the liquid jet head 2, and can be made of an elastically deformable material, such as rubber or elastomer. The sealing member 203 is provided with a third supply flow path 403 and a third recovery flow path 413 that penetrate in the Z-axis direction, with the first supply flow path 401 and the second supply flow path 402 communicating with each other via the third supply flow path 403, and the first recovery flow path 411 and the second recovery flow path 412 communicating with each other via the third recovery flow path 413. In other words, the flow path structure 200 has four supply flow paths 400, and each supply flow path 400 has a first supply flow path 401, a second supply flow path 402, and a third supply flow path 403. The flow path structure 200 also has four recovery flow paths 410, and each recovery flow path 410 has a first recovery flow path 411, a second recovery flow path 412, and a third recovery flow path 413.

[0033] The second flow path member 202 has a storage portion 230 having a recessed shape that opens on a surface facing the +Z direction. The head chips 8 are stored in the storage portion 230. In this embodiment, the liquid jet head 2 is equipped with a plurality of head chips 8, for example, two head chips 8. Of the two head chips 8, the one on the -Y direction side is also referred to as head chip 8a, and the one on the +Y direction side is also referred to as head chip 8b. The two head chips 8 are held in a single common storage portion 230. The number of head chips 8 held by the liquid jet head 2 is not particularly limited to this, and may be one, or two or more. Furthermore, the storage portion 230 may be provided independently for each head chip 8, or may be provided for each head chip group consisting of two or more head chips 8.

[0034] In this embodiment, the two head chips 8 are arranged side by side in the Y-axis direction so that they are at the same position in the X-axis direction. The surface of the head chip 8 facing the -Z direction and the bottom surface of the storage section 230, i.e., the surface facing the +Z direction, are bonded with an adhesive (not shown). The bottom surface of the storage section 230 bonded to the head chip 8 is referred to as the flow path connection surface 231. Here, the "flow path connection surface" of the flow path structure 200 refers to the surface at the height with the largest surface area among the surfaces facing the +Z plane of the flow path structure 200, when multiple surfaces with different heights in the Z-axis direction exist. For example, the surface facing the +Z direction of the flow path structure 200 may have steps formed by recesses, protrusions, etc., and the "flow path connection surface" refers to the surface facing the +Z direction at the largest surface area among the surfaces with different heights in the Z-axis direction, including these recesses and protrusions.

[0035] The arrangement of the plurality of head chips 8 is not particularly limited to this.

[0036] A second supply flow path 402 and a second recovery flow path 412 open to the flow path connection surface 231 of the second flow path member 202. Each inlet 44a of the head chip 8 communicates with the second supply flow path 402 that opens to the flow path connection surface 231, and each outlet 44b (see FIG. 5) of the head chip 8 communicates with the second recovery flow path 412 that opens to the flow path connection surface 231. In this embodiment, two second supply flow paths 402 are provided for one head chip 8, and the openings of the two second supply flow paths 402 in the flow path connection surface 231 are arranged side by side in the Y-axis direction. Furthermore, two second recovery flow paths 412 are provided for one head chip 8, and the openings of the two second recovery flow paths 412 in the flow path connection surface 231 are arranged side by side in the Y-axis direction.

[0037] The second flow path member 202 has a first wiring insertion hole 205 penetrating through along the Z-axis direction. One end of the first wiring insertion hole 205 opens to the surface of the second flow path member 202 facing the -Z direction, and the other end opens to the flow path connection surface 231. The wiring member 110 of the head chip 8, which will be described in detail later, is led out to the surface of the second flow path member 202 facing the -Z direction through the first wiring insertion hole 205. In this embodiment, one first wiring insertion hole 205 is provided for each of the two head chips 8. The opening of the first wiring insertion hole 205 is located on the flow path connection surface 231 of the accommodating section 230 between the openings of the two second supply flow paths 402 aligned in the Y-axis direction and between the openings of the two second recovery flow paths 412 aligned in the Y-axis direction.

[0038] In the Z-axis direction, a relay substrate 210 to which the wiring members 110 of the plurality of head chips 8 are commonly connected is provided between the sealing member 203 and the second flow path member 202. The relay substrate 210 is made of a hard, rigid substrate with no flexibility, and wiring, electronic components, and the like (not shown) are mounted on the relay substrate 210. In the present embodiment, as an example of the electronic components, a connector 211 to which the wiring members 110 of the head chip 8 are connected, and an external wiring connector 212 to which external wiring (not shown) provided outside the liquid jet head 2 is connected are illustrated. Note that the wiring member 110 is detachable from the connector 211. Printing signals and the like for controlling the head chips 8 are input to the relay substrate 210 from the external wiring via the external wiring connector 212, and are supplied to each head chip 8 via the connector 211 and the wiring members 110 of the relay substrate 210. An external wiring opening 206 is provided on the side wall of the flow path structure 200 facing the external wiring connector 212, for inserting an external wiring connected to the external wiring connector 212. The external wiring is connected to the external wiring connector 212 of the relay substrate 210 provided inside the flow path structure 200 through the external wiring opening 206.

[0039] The relay substrate 210 has a second wiring insertion hole 213 that penetrates along the Z-axis direction. The second wiring insertion hole 213 is disposed at a position that communicates with the first wiring insertion hole 205, that is, at a position that overlaps with the first wiring insertion hole 205 when viewed in the Z-axis direction. The wiring member 110 of the head chip 8 is led out to the surface of the relay substrate 210 facing the -Z direction through the first wiring insertion hole 205 and the second wiring insertion hole 213.

[0040] Intermediate substrate 210 has protrusion insertion holes 214 that penetrate in the Z-axis direction. Cylindrical protrusions 207, which have second supply flow paths 402 or second recovery flow paths 412 provided therein, are provided on the surface of second flow path member 202 facing the -Z direction so as to protrude in the -Z direction. Protrusions 207 are inserted into the -Z direction side of intermediate substrate 210 via protrusion insertion holes 214, and second supply flow paths 402 or second recovery flow paths 412 provided in protrusions 207 are connected to third supply flow paths 403 or third recovery flow paths 413.

[0041] A cover 220 is fixed to the surface of the flow path structure 200 facing the +Z direction. The cover 220 is made of a metal plate such as stainless steel, and is large enough to cover the accommodation portion 230 of the flow path structure 200. The cover 220 is a common member fixed to the surfaces of the two head chips 8 facing the +Z direction. The cover 220 is provided with an exposure opening 221 that exposes the nozzles 21 of the head chip 8 in the +Z direction, independently for each head chip 8. Ink is ejected in the +Z direction from the nozzles 21 exposed from the exposure opening 221.

[0042] Fig. 5 is an exploded perspective view of the head chip 8 according to one embodiment of the present invention. Fig. 6 is a plan view of the pressure chamber substrate 10. Fig. 7 is a cross-sectional view of the head chip 8 and the cover 220 taken along line BB in Fig. 6. Fig. 8 is a plan view of the head chip. Note that the directions of the head chip 8 will be described based on the directions when the head chip 8 is mounted on the liquid jet head 2, i.e., the X-axis direction, Y-axis direction, and Z-axis direction.

[0043] The head chip 8 of this embodiment comprises a pressure chamber substrate 10, a communication plate 15, a nozzle plate 20 in which a plurality of nozzles 21 are formed, a protective substrate 30, a case member 40, a piezoelectric actuator 300, and a wiring member 110.

[0044] The pressure chamber substrate 10 is made of, for example, a silicon substrate. In the pressure chamber substrate 10, a plurality of pressure chambers 12 are arranged side by side along the X-axis direction. The plurality of pressure chambers 12 are arranged side by side along the X-axis direction so as to be at the same position in the Y-axis direction. They are arranged in a line. Two pressure chambers 12 adjacent to each other in the X-axis direction are separated by a partition wall (not shown). In this embodiment, two pressure chamber rows in which the pressure chambers 12 are arranged side by side along the X-axis direction are provided in the Y-axis direction.

[0045] A communication plate 15 and a nozzle plate 20 are stacked in this order on the surface of the pressure chamber substrate 10 facing the +Z direction. A vibration plate 50 and a piezoelectric actuator 300 are stacked in this order on the surface of the pressure chamber substrate 10 facing the -Z direction.

[0046] The communicating plate 15 is made of a plate-like member bonded to the surface of the pressure chamber substrate 10 facing the +Z direction. The communicating plate 15 is provided with nozzle communicating passages 16 that communicate between the pressure chambers 12 and the nozzles 21. The communicating plate 15 is also provided with a first common liquid chamber section 17 and a second common liquid chamber section 18 that constitute a common liquid chamber 100 that communicates with a plurality of pressure chambers 12. The first common liquid chamber section 17 is provided by penetrating the communicating plate 15 in the Z-axis direction. The second common liquid chamber section 18 is provided by opening onto the surface facing the +Z direction without penetrating the communicating plate 15 in the Z-axis direction. Furthermore, the communicating plate 15 is provided with supply communicating passages 19 that communicate with one end of the pressure chambers 12 in the Y-axis direction, independently for each pressure chamber 12. The supply communication passage 19 communicates the second common liquid chamber portion 18 with the pressure chamber 12, and supplies ink in the common liquid chamber 100 to the pressure chamber 12. As such a communication plate 15, a silicon substrate or the like can be used.

[0047] The nozzle plate 20 is bonded to the surface of the communication plate 15 facing the +Z direction. Nozzles 21 are formed in the nozzle plate 20, which communicate with each pressure chamber 12 via nozzle communication passages 16. In this embodiment, the multiple nozzles 21 are arranged in a row along the X-axis direction. Also, in this embodiment, two nozzle rows, in which the nozzles 21 are arranged side by side along the X-axis direction, are provided spaced apart in the Y-axis direction.

[0048] The material of the nozzle plate 20 is not particularly limited, and for example, a silicon substrate or the like can be used.

[0049] The vibration plate 50 has, for example, an elastic film 51 made of silicon oxide provided on the pressure chamber substrate 10 side, and an insulating film 52 made of zirconium oxide provided on the surface of the elastic film 51 facing the -Z direction.

[0050] The piezoelectric actuator 300 includes a first electrode 60 sequentially stacked in the -Z direction on the diaphragm 50, a piezoelectric layer 70 formed using a piezoelectric material, for example, a composite oxide with a perovskite structure represented by the general formula ABO3, and a second electrode 80. Such a piezoelectric actuator 300 is also referred to as a piezoelectric element, and refers to a portion including the first electrode 60, the piezoelectric layer 70, and the second electrode 80. Furthermore, a portion of the piezoelectric layer 70 where piezoelectric strain occurs when a voltage is applied between the first electrode 60 and the second electrode 80 is referred to as an active portion 310. In contrast, a portion of the piezoelectric layer 70 where no piezoelectric strain occurs is referred to as an inactive portion. In other words, the active portion 310 refers to the portion of the piezoelectric layer 70 sandwiched between the first electrode 60 and the second electrode 80. In this embodiment, an active portion 310 is formed for each pressure chamber 12. In other words, the piezoelectric actuator 300 is formed with multiple active portions 310. The plurality of active portions 310 serve as driving elements that cause pressure changes in the ink within the pressure chambers 12. Generally, one of the electrodes of the active portions 310 is configured as an individual electrode that is independent for each active portion 310, and the other electrode is configured as a common electrode that is common to the plurality of active portions 310. In this embodiment, the first electrode 60 constitutes the individual electrode, and the second electrode 80 constitutes the common electrode.

[0051] An individual lead electrode 90, which serves as a lead wiring, is drawn out from the first electrode 60. A common lead electrode (not shown), which serves as a lead wiring, is drawn out from the second electrode 80. A wiring member 110 made of a flexible substrate is connected to the ends of the individual lead electrodes 90 and the common lead electrode opposite to the ends connected to the piezoelectric actuator 300. The wiring member 110 is mounted with a drive circuit 111 having a plurality of switching elements that select whether or not to supply a drive signal (COM) for driving each active portion 310 to each active portion 310. In other words, the wiring member 110 in this embodiment is a chip-on-film (COF). Note that the wiring member 110 does not necessarily have to be provided with the drive circuit 111. In other words, the wiring member 110 may be a flexible flat cable (FFC), flexible printed circuits (FPC), or the like.

[0052] A protective substrate 30 having approximately the same size as the pressure chamber substrate 10 is bonded to the surface of the pressure chamber substrate 10 facing the -Z direction. The protective substrate 30 has accommodation sections 31, which are spaces for protecting the piezoelectric actuators 300. The accommodation sections 31 are provided independently for each row of piezoelectric actuators 300 arranged side by side in the X-axis direction, with two accommodation sections 31 formed side by side in the Y-axis direction. The protective substrate 30 also has a through hole 32 penetrating in the Z-axis direction between two accommodation sections 31 arranged side by side in the Y-axis direction. Ends of the individual lead electrodes 90 and common lead electrode drawn from the electrodes of the piezoelectric actuators 300 extend so as to be exposed within the through hole 32, and the individual lead electrodes 90 and common lead electrode are electrically connected to the wiring member 110 within the through hole 32. Such a protective substrate 30 may be made of, for example, a silicon substrate.

[0053] A case member 40 that defines a common liquid chamber 100 that communicates with the multiple pressure chambers 12 is fixed on the protective substrate 30. The case member 40 has substantially the same shape as the above-mentioned communicating plate 15 in a plan view, and is bonded to the protective substrate 30 as well as to the above-mentioned communicating plate 15.

[0054] The case member 40 has a recess 41 on the protective substrate 30 side that is deep enough to accommodate the pressure chamber substrate 10 and the protective substrate 30. This recess 41 has an opening area that is larger than the surface of the protective substrate 30 that is bonded to the pressure chamber substrate 10. Then, with the pressure chamber substrate 10 and the protective substrate 30 accommodated in the recess 41, the opening surface of the recess 41 on the nozzle plate 20 side is sealed by the communicating plate 15.

[0055] The case member 40 is provided with a third common liquid chamber 42 that communicates with the first common liquid chamber 17 of the communication plate 15. The first common liquid chamber 17 and second common liquid chamber 18 provided in the communication plate 15 and the third common liquid chamber 42 provided in the case member 40 constitute a common liquid chamber 100 of this embodiment. A total of two common liquid chambers 100 are provided, one for each row of pressure chambers 12. Each common liquid chamber 100 is provided continuously along the X-axis direction in which the pressure chambers 12 are arranged side by side, and the supply communication passages 19 that communicate each pressure chamber 12 with the common liquid chamber 100 are arranged side by side in the X-axis direction. The case member 40 is also provided with an inlet 44a and an outlet 44b. The inlet 44a and the outlet 44b are open on the surface of the case member 40 facing the -Z direction and communicate with the common liquid chamber 100. The inlet 44a is connected to the supply flow path 400 and is a flow path for introducing ink from the supply flow path 400 to the common liquid chamber 100. The outlet 44b is connected to the recovery flow path 410 and is a flow path for returning ink from the common liquid chamber 100 to the recovery flow path 410. The case member 40 is also provided with a connection port 43 that communicates with the through hole 32 of the protective substrate 30 and through which the wiring member 110 is inserted. The connection port 43 is provided to open on the surface of the case member 40 facing the +Z direction. The connection port 43 is also disposed between the two inlet ports 44a in the Y-axis direction and between the two outlet ports 44b in the Y-axis direction. The connection port 43 has an elongated opening shape extending along the X-axis direction as viewed in the +Z direction. The wiring member 110 of the head chip 8 is led out through the connection port 43 to the surface of the liquid jet head 2 facing the -Z direction. The case member 40 is made of a material such as a metal material, a resin material, or the like.

[0056] A compliance substrate 45 is provided on the surface of the communicating plate 15 on the +Z direction side where the first common liquid chamber portion 17 and the second common liquid chamber portion 18 open. This compliance substrate 45 seals the openings of the first common liquid chamber portion 17 and the second common liquid chamber portion 18 on the ejection surface 20a side. In this embodiment, such a compliance substrate 45 includes a sealing film 46 made of a flexible thin film, and a fixed substrate 47 made of a hard material such as metal. The area of the fixed substrate 47 facing the common liquid chamber 100 is an opening 48 that is completely removed in the thickness direction, and therefore one side of the common liquid chamber 100 forms a compliance portion 49 that is a flexible portion sealed only by the flexible sealing film 46.

[0057] A cover 220 is bonded to the surface of the compliance substrate 45 facing the +Z direction. That is, the cover 220 is bonded to the fixed substrate 47 so as to cover the opening 48. The fixed substrate 47 defines a compliance space inside the opening 48 in which the compliance section 49 can bend and deform. The space between the cover 220 and the sealing film 46 is open to the atmosphere, allowing the compliance section 49 of the sealing film 46 to deform in response to the pressure of the ink in the common liquid chamber 100.

[0058] In this liquid jet head 2, ink is supplied to the supply flow path 400 of the flow path structure 200 connected to the sub-tank 3b. Foreign matter such as dust and air bubbles contained in the ink is removed by a filter 401b provided in the flow path structure 200, and the ink is supplied to the common liquid chamber 100 via the inlet 44a of the head chip 8. After the ink fills the interior from the common liquid chamber 100 to the nozzles 21, a voltage is applied to each active portion 310 corresponding to the pressure chambers 12 in accordance with a recording signal from the drive circuit 111. This causes the active portion 310 and the diaphragm 50 to flex and deform, increasing the pressure of the ink in each pressure chamber 12 and causing ink droplets to be ejected from each nozzle 21. Ink that is not ejected from the nozzles 21 is recovered from the common liquid chamber 100 to the sub-tank 3b via the outlet 44b and the recovery flow path 410.

[0059] 5, 7, and 8, the liquid holding portion provided in head chip 8 will be described. A first recess group 131 and a second recess group 132 are provided on the upper surface of head chip 8 facing the -Z direction, which in this embodiment is upper surface 40a of case member 40 facing the -Z direction.

[0060] The "top surface" of head chip 8 refers to the surface facing the -Z direction of the component located furthest in the -Z direction of head chip 8, and when there are multiple surfaces of different heights in the Z-axis direction, the surface at the height that has the largest surface area among them. For example, the surface facing the -Z direction of case component 40, which is the component located furthest in the -Z direction of head chip 8, may have steps formed by recesses, protrusions, etc., but the "top surface" refers to the surface facing the -Z direction of the portion of the case component 40 that has the largest surface area among the surfaces of different heights in the Z-axis direction, including these recesses and protrusions. In this embodiment, the surface facing the -Z direction of case component 40 is formed as a flat surface without any steps, and this surface is top surface 40a.

[0061] The first recess group 131, as will be described in detail later, has a configuration capable of retaining leaked liquid when the flow path connection between the head chip 8 and the flow path structure 200 is released. In this embodiment, the first recess group 131 includes a plurality of recesses 140 recessed in the +Z direction relative to the upper surface 40a, and a first groove portion 151 formed in a rectangular frame shape along the upper surface 40a so as to surround the connection port 43 when viewed in the +Z direction. Furthermore, at least a portion of the first recess group 131 is disposed between the inlet port 44a and the outlet port 44b and the connection port 43 when viewed in the +Z direction. In this embodiment, as shown in FIGS. 8 and 9 , the first recess group 131 is arranged in the Y-axis direction so that the connection port 43 is disposed between two inlet ports 44a. Specifically, a portion of the first recess group 131, i.e., several recesses 140 and a portion of the first groove portion 151 connecting the recesses 140, is disposed between one inlet port 44a and the connection port 43 on the -Y direction side, and between one inlet port 44a and the connection port 43 on the +Y direction side.

[0062] The second recess group 132, which will be described in detail later, has a configuration capable of holding liquid that leaks when the flow path connection between the head chip 8 and the flow path structure 200 is released. In this embodiment, the second recess group 132 includes a plurality of recesses 140 recessed in the +Z direction relative to the upper surface 40a, and a second groove portion 152 in the shape of a rectangular frame that follows the outer edge of the upper surface 40a and surrounds the connection port 43, the inlet port 44a, and the outlet port 44b when viewed in the +Z direction.

[0063] As described above, the top surface 40a of the head chip 8 is provided with the first recess group 131 and the second recess group 132, which are capable of retaining liquid that leaks when the flow path connection is released. Portions of the top surface 40a where the first recess group 131 and the second recess group 132 are not provided are liquid-non-retaining portions that do not retain leaked liquid. Not retaining leaked liquid means that the liquid is less likely to be retained on the liquid-non-retaining portions compared to the first recess group 131 and the second recess group 132. In this embodiment, the liquid-non-retaining portions are part of the top surface 40a and are planar, and therefore are less likely to retain liquid than the first recess group 131 and the second recess group 132, which have recesses 140. Note that the liquid-non-retaining portions are not limited to being planar, and may be inclined, for example, so that liquid flows toward the first recess group 131 and the second recess group 132.

[0064] The plurality of recesses 140 constituting each of the first recess group 131 and the second recess group 132 includes adjacent first recesses 141 and second recesses 142. That is, of any two adjacent recesses 140 among the plurality of recesses 140, one is the first recess 141 and the other is the second recess 142. The first recess group 131 is formed by connecting any two adjacent recesses among the plurality of recesses 140, the first recess 141 and the second recess 142, by a part of a first groove portion 151. Similarly, the second recess group 132 is formed by connecting the first recess 141 and the second recess 142 by a part of a second groove portion 152.

[0065] The spacing between the first recesses 141 and the second recesses 142 is not particularly limited, and not all spacing needs to be uniform. In the example shown in FIG. 8 , the first recess group 131 does not have recesses 140 between the inlet 44a and outlet 44b and the connection port 43. As described above, if a sufficient area for providing the recesses 140 cannot be secured between the inlet 44a and outlet 44b and the connection port 43, but a sufficient area for providing the first grooves 151 can be secured, it is preferable to form the first recess group 131 including the recesses 140 and the first grooves 151 as in this embodiment. With such a first recess group 131, even if a sufficient area for providing the recesses 140 cannot be secured, the first grooves 151 can be provided in the area to form the first recess group 131 surrounding the connection port 43. Furthermore, it is preferable that the surface of the first grooves 151 be highly liquid-repellent and that the surface of the recesses 140 be less liquid-repellent than the surface of the first grooves 151. For example, by providing a liquid-repellent film only on the surface of first groove portion 151, the surface of first groove portion 151 can have high liquid repellency, and the surface of recess 140 can have lower liquid repellency than first groove portion 151. Such a liquid-repellent film can be formed from, for example, a fluorine-containing organic compound or a fluorine-containing organic silicon compound.

[0066] In this embodiment, recess 140 is a so-called dimple, in which the opening shape on upper surface 40a is substantially circular and the cross-sectional shape in a cross section perpendicular to upper surface 40a is hemispherical. Note that recess 140 is not limited to such a shape, and the opening shape may be elliptical or polygonal, and the cross-sectional shape may be elliptical or polygonal. The surface of recess 140 is preferably hydrophilic. Specifically, it is preferable that the surface of recess 140 is more hydrophilic than the surface of the liquid non-holding portion. By making the surface of recess 140 hydrophilic, it becomes easier for first recess group 131 to reliably hold liquid that has leaked onto upper surface 40a when head chip 8 and flow path structure 200, which will be described later, are disconnected.

[0067] The depth and opening area of recess 140 are preferably such that ink held in recess 140 does not flow out even when upper surface 40a of head chip 8 is oriented in the direction of gravity.

[0068] In this embodiment, the first groove portion 151 and the second groove portion 152 are formed linearly and are narrower than the width of the recessed portion 140 when viewed in the +Z direction. The cross-sectional shape, depth, width, and the like of each of the first groove portion 151 and the second groove portion 152 are preferably sized so that capillary force acts on the ink. Furthermore, the first groove portion 151 and the second groove portion 152 may be inclined so that liquid flows into adjacent first recessed portions 141 and / or second recessed portions 142. Of course, the first groove portion 151 and the second groove portion 152 are not limited to such shapes. Furthermore, there are no particular limitations on the number of recessed portions 140 provided in the first groove portion 151 and the second groove portion 152, or the spacing between the first recessed portion 141 and the second recessed portion 142.

[0069] 9 is a cross-sectional view of the liquid jet head 2 when the flow path connection between the head chip 8 and the flow path structure 200 is released. In this embodiment, releasing the flow path connection means that, by removing the head chip 8 from the flow path structure 200, the connection between the supply flow path 400 and the inlet 44a is released, and the connection between the recovery flow path 410 and the outlet 44b is released.

[0070] When the liquid jet head 2 is disassembled into the flow path structure 200 and the head chip 8 with the ejection surface 20a of the nozzle plate 20 facing vertically downward, i.e., facing the +Z direction, there is a risk that the liquid 500 leaking from the supply flow path 400, the recovery flow path 410, the inlet 44a, or the outlet 44b may adhere to the upper surface 40a. However, by providing the first recess group 131, the liquid 500 adhering to the upper surface 40a flows into the first recess group 131 and is retained within the first recess group 131. Such a first recess group 131 can prevent the liquid 500 adhering to the upper surface 40a from penetrating into the head chip 8 through the connection port 43. Therefore, it is possible to prevent the liquid 500 that has entered the connection port 43 from adhering to the connection portion between the wiring member 110 and the individual lead electrode 90 or the common lead electrode (not shown), thereby preventing electrical malfunctions such as short-circuiting between wirings.

[0071] Furthermore, by providing second recess group 132, liquid 500 adhering to upper surface 40a flows into second recess group 132 and is held within second recess group 132. Such second recess group 132 can prevent liquid 500 adhering to upper surface 40a from flowing onto the side surface of head chip 8 and soiling the side surface of the head chip and ejection surface 20a.

[0072] As described above, the liquid jet head 2 of this embodiment includes the head chip 8 and the flow path structure 200. The head chip 8 has an inlet 44a and an outlet 44b for liquid-tightly connecting to the supply flow path 400 and the recovery flow path 410 of the flow path structure 200, and also has an upper surface 40a. The upper surface 40a is provided with a first recess group 131 that can hold liquid that leaks when the flow path connection between the head chip 8 and the flow path structure 200 is released, and a liquid non-holding portion that does not hold the leaked liquid.

[0073] According to such a liquid jet head 2, when disassembled into the head chip 8 and the flow path structure 200 as shown in FIG. 9 , the liquid 500 leaking from the supply flow path 400, the recovery flow path 410, the inlet 44a, or the outlet 44b can be retained in the first recess group 131, thereby preventing the liquid 500 from entering the connection port 43. This prevents the liquid from adhering to the wiring member 110, the drive circuit 111, or wiring or electronic components (not shown) around the connection port 43, causing electrical malfunctions such as short-circuiting between wiring. Since the liquid jet head 2 can be easily disassembled while preventing the leaked liquid from entering the head chip 8 when the flow path connection is released, for example, a defective head chip 8 can be easily replaced. By replacing a defective part of the liquid jet head 2, i.e., at least one of the multiple head chips 8 or the flow path structure 200, the life of the liquid jet head 2 can be extended, and non-defective parts can be reused.

[0074] In the present embodiment, the inlet 44a and outlet 44b provided in the case member 40 are exemplified as the flow path connecting portion, but the present invention is not limited to this configuration. For example, the flow path connecting portion may be a flow path pipe protruding from the upper surface 40a in the -Z direction. The connection between the head chip 8 and the flow path structure 200 is not particularly limited, and may be, for example, bonded with an adhesive or connected via a sealing member. The head chip 8a is an example of a "head chip." The +Z direction is an example of a "first direction," and the -Z direction is an example of a "second direction." The supply flow path 400 and the recovery flow path 410 are examples of a "flow path." The inlet 44a and outlet 44b are examples of a "flow path connecting portion." The first recess group 131 is an example of a "first liquid holding portion."

[0075] In the liquid jet head 2 of this embodiment, the head chip 8 has a wiring member 110, and the upper surface 40a is provided with a connection port 43 into which the wiring member 110 is inserted. According to such a liquid jet head 2, liquid that leaks onto the upper surface 40a is retained in the first recess group 131, thereby reducing the intrusion of liquid into the connection port 43 formed on the upper surface 40a and suppressing damage to the electrical connection portion between the piezoelectric actuator 300 of the head chip 8 and the wiring member. The wiring member 110 is an example of a "flexible substrate," and the connection port 43 is an example of an "opening into which a flexible substrate is inserted."

[0076] In the liquid jet head 2 of this embodiment, several recesses 140 that are at least a part of the first recess group 131 and a part of the first groove portion 151 that connects these recesses 140 are arranged between the inlet 44 a and the outlet 44 b and the connection port 43 when viewed in the +Z direction. Liquid 500 that leaks when the head chip 8 and the flow path structure 200 are disconnected is likely to fall around the inlet 44 a and the outlet 44 b. In this embodiment, at least a part of the first recess group 131 is arranged between the inlet 44 a and the outlet 44 b and the connection port 43, so that the liquid can be more effectively held in the first recess group 131 and the infiltration of the liquid into the head chip 8 via the connection port 43 can be more reliably prevented.

[0077] In the liquid jet head 2 of this embodiment, the first recessed portion group 131 is provided so as to surround the connection port 43 when viewed in the +Z direction. Such a first recessed portion group 131 can more reliably prevent the liquid 500 leaking onto the upper surface 40a from entering the head chip 8 via the connection port 43.

[0078] In the liquid jet head 2 of this embodiment, the upper surface 40a is provided with a second recess group 132 that is arranged along the outer edge of the upper surface 40a when viewed in the +Z direction and is capable of holding leaked liquid 500. By providing the second recess group 132, the liquid 500 adhering to the upper surface 40a flows into the second recess group 132 and can be held within the second recess group 132. This prevents the liquid 500 adhering to the upper surface 40a from flowing onto the side surface of the head chip 8 and contaminating the side surface of the head chip 8 and the ejection surface 20a with the liquid 500. The second recess group 132 is an example of a "second liquid holding portion."

[0079] In the liquid jet head 2 of this embodiment, the first recessed portion group 131 includes a plurality of recessed portions 140 recessed in the +Z direction with respect to the upper surface 40a, and a first groove portion 151 recessed in the +Z direction with respect to the upper surface 40a and extending along the upper surface 40a. The plurality of recessed portions 140 also include adjacent first recessed portions 141 and second recessed portions 142, and the first recessed portions 141 and second recessed portions 142 are connected by a portion of the first groove portion 151. The first groove portion 151 is an example of a "groove recessed in the first direction with respect to the upper surface and extending along the upper surface." Since the first recessed portion group 131 includes a plurality of recessed portions 140 and the first groove portion 151 connecting them, even if the liquid 500 flows into some of the recessed portions 140 or some of the first groove portions 151 in a concentrated manner, the liquid 500 is dispersed and retained in the other recessed portions 140. Such a first recess group 131 can more reliably prevent the liquid 500 from entering the connection port 43. Similarly, the second recess group 132 can more reliably prevent the liquid 500 from contaminating the side surface of the head chip 8 or the ejection surface 20a. Furthermore, by providing the first recess group 131 including the recess 140 and the first groove 151, even if a sufficient area for providing the recess 140 cannot be secured, such as the area between the inlet 44a and outlet 44b and the connection port 43, the first groove 151 narrower than the recess 140 can be provided in the area to form the first recess group 131 surrounding the connection port 43, thereby preventing the liquid from entering the connection port 43. Furthermore, it is preferable that the surface of the first groove 151 is highly liquid-repellent and the surface of the recess 140 is less liquid-repellent than the surface of the first groove 151. This makes it easier for the liquid held in the first groove 151 to move to the recess 140 and improves the liquid-holding power of the recess 140. Furthermore, the first groove portion 151 and the second groove portion 152 are inclined so that liquid flows into the adjacent first recess 141 and / or second recess 142, thereby making it easier to move the liquid held in the first groove portion 151 and the second groove portion 152 to the recess 140.

[0080] The liquid jet head 2 of this embodiment includes a head chip 8b that ejects liquid in the +Z direction, and the head chip 8b has an inlet 44a and an outlet 44b for liquid-tight connection with the supply flow path 400 and the recovery flow path 410 in the flow path structure 200, and has an upper surface 40a facing the -Z direction, and a first recessed portion group 131 that can hold liquid is provided on the upper surface 40a of the head chip 8b. The head chip 8b is an example of a "second head chip," and the first recessed portion group 131 of the head chip 8b is an example of a "third liquid holding portion."

[0081] (Variation 1) 10 is a plan view seen in the +Z direction of a modified example of head chip 8 of embodiment 1. Head chip 8 according to modified example 1 has first recess group 131A and second recess group 132A provided on top surface 40a.

[0082] The first recess group 131A has a configuration capable of retaining liquid leaked when the flow path connection between the head chip 8 and the flow path structure 200 is released. Specifically, the first recess group 131A includes a plurality of recesses 140 recessed in the +Z direction with respect to the upper surface 40a. The plurality of recesses 140 are provided so as to surround the connection port 43. That is, the first recess group 131A surrounds the connection port 43 by including a plurality of recesses 140 that are not connected by a groove and are arranged side by side so as to surround the connection port 43 at intervals. The spacing between the recesses 140 in the first recess group 131A is not particularly limited, but it is preferable to set the spacing so that even if liquid leaking to the upper surface 40a reaches between adjacent recesses 140, it flows into the recesses 140. Furthermore, at least a portion of the first recess group 131A is disposed between the inlet 44a and the outlet 44b and the connection port 43 when viewed in the +Z direction. In the present embodiment, a portion of first recess group 131A, i.e., several recesses 140, are arranged between one inlet 44a and connection port 43 on the -Y direction side, and are also arranged between one inlet 44a and connection port 43 on the +Y direction side. Furthermore, a portion of first recess group 131A, i.e., several recesses 140, are arranged between one outlet 44b and connection port 43 on the -Y direction side, and are also arranged between one outlet 44b and connection port 43 on the +Y direction side. First recess group 131A, which is composed of a plurality of recesses 140 spaced apart in this manner, achieves the same effects as first recess group 131 of embodiment 1.

[0083] The second recess group 132A has a configuration capable of retaining liquid that leaks when the flow path connection between the head chip 8 and the flow path structure 200 is released, and includes a plurality of recesses 140 spaced apart, similar to the first recess group 131A. The second recess group 132A is arranged in a rectangular frame shape along the outer edge of the upper surface 40a so as to surround the connection port 43, the inlet port 44a, and the outlet port 44b when viewed in the +Z direction. The spacing between the recesses 140 in the second recess group 132A is also similar to that of the first recess group 131A. The second recess group 132A, which is composed of a plurality of recesses 140 spaced apart in this manner, achieves the same effects as the second recess group 132 of the first embodiment. The first recess group 131A is an example of a "first liquid retaining portion," and the second recess group 132A is an example of a "second liquid retaining portion."

[0084] (Variation 2) 11 is a plan view seen in the +Z direction of a modification of head chip 8 of embodiment 1. Head chip 8 according to modification 2 has first groove 151A and second groove 152A provided on top surface 40a.

[0085] First groove 151A has a configuration capable of retaining liquid that leaks when the flow path connection between head chip 8 and flow path structure 200 is released. Specifically, first groove 151A is recessed in the +Z direction with respect to upper surface 40a and extends along upper surface 40a. When viewed in the +Z direction, first groove 151A is formed in a rectangular frame shape and is continuous so as to surround connection port 43. In other words, the mode surrounding connection port 43 does not include multiple recesses, but includes first groove 151A in a continuous frame shape. The width, depth, cross-sectional shape, and the like of first groove 151A are preferably sized so that ink retained in first groove 151A does not flow out even when upper surface 40a of head chip 8 is oriented in the direction of gravity. In addition, the surface of first groove 151A is preferably hydrophilic. That is, the surface of the first groove portion 151A is preferably more hydrophilic than the surface of a liquid non-retaining portion of the upper surface 40a that does not have the first groove portion 151A or the second groove portion 152A. Furthermore, at least a portion of the first groove portion 151A is disposed between the inlet 44a and the outlet 44b and the connection port 43 when viewed in the +Z direction. In this embodiment, a portion of the first groove portion 151A is disposed between the single inlet 44a and the connection port 43 on the -Y direction side, and another portion is disposed between the single inlet 44a and the connection port 43 on the +Y direction side. The first groove portion 151A disposed so as to surround the connection port 43 in this manner achieves the same effects as the first recess group 131 of the first embodiment.

[0086] The second groove portion 152A is configured to retain liquid that leaks when the flow path connection between the head chip 8 and the flow path structure 200 is released. Specifically, the second groove portion 152A is recessed in the +Z direction relative to the upper surface 40a and extends along the upper surface 40a. The second groove portion 152A is provided in the shape of a rectangular frame along the outer edge of the upper surface 40a so as to surround the connection port 43, the inlet port 44a, and the outlet port 44b when viewed in the +Z direction. The surface of the second groove portion 152A is preferably more hydrophilic than the surface of the liquid non-retaining portion. The second groove portion 152A exhibits the same effects as the second recess group 132 of the first embodiment. The first groove portion 151A is an example of a "first liquid retaining portion," and the second groove portion 152A is an example of a "second liquid retaining portion."

[0087] (Variation 3) 12 is a plan view of a modified example of head chip 8 of embodiment 1, viewed in the +Z direction. Top surface 40a of head chip 8 according to modified example 3 includes first region 161 and second region 162.

[0088] In this embodiment, the first region 161 includes an inner region 161a and an outer region 161b. The inner region 161a extends along the upper surface 40a and, when viewed in the +Z direction, is provided in the shape of a continuous rectangular frame surrounding the connection port 43. The outer region 161b, when viewed in the +Z direction, is formed in the shape of a rectangular frame along the outer edge of the upper surface 40a surrounding the connection port 43, the inlet port 44a, and the outlet port 44b. The second region 162 is a region between the inner region 161a and the outer region 161b. A portion of the inner region 161a is disposed between one inlet 44a and the connection port 43 on the -Y direction side, and another portion is disposed between one inlet 44a and the connection port 43 on the +Y direction side. Furthermore, a portion of the inner region 161a is positioned between one outlet 44b on the -Y direction side and the connection port 43, and another portion is positioned between one outlet 44b on the +Y direction side and the connection port 43.

[0089] The second region 162 has lower liquid repellency than the first region 161. For example, by forming a liquid repellent film on a part of the upper surface 40a of the case member 40, which is made of a metal material, a resin material, or the like, to form the first region 161, the part where the liquid repellent film is not formed can be made into the second region 162. The liquid repellent film can be formed from, for example, a fluorine-containing organic compound or a fluorine-containing organic silicon compound.

[0090] The second region 162 is capable of retaining leaked liquid when the flow path connection between the head chip 8 and the flow path structure 200 is released. Furthermore, since the inner region 161a has higher liquid repellency than the second region 162, even if the leaked liquid attempts to enter the connection port 43, it is repelled by the inner region 161a and retained in the second region 162. Similarly, even if the liquid leaked onto the second region 162 attempts to flow from the second region 162 toward the side surface of the head chip 8, it is repelled by the outer region 161b and retained in the second region 162. Thus, since the second region 162 has lower liquid repellency than the inner region 161a and the outer region 161b of the first region 161, it can retain leaked liquid, thereby achieving the same effect as the first recess group 131 of the first embodiment. The second region 162 is an example of a "first liquid retaining portion." The first region 161 is an example of a "liquid non-retaining portion."

[0091] (Variation 4) 13 is a plan view of a modified example of head chip 8 of embodiment 1 as viewed in the +Z direction. Head chip 8 according to modified example 4 has first groove portion 151B and second groove portion 152B formed on top surface 40a. Head chip 8 also has one inlet 44a and one outlet 44b.

[0092] The first groove portion 151B has a configuration capable of retaining liquid that leaks when the flow path connection between the head chip 8 and the flow path structure 200 is released. Specifically, the first groove portion 151B is recessed in the +Z direction with respect to the upper surface 40a and extends linearly along the upper surface 40a. Furthermore, at least a portion of the first groove portion 151B is disposed between the inlet 44a and the outlet 44b and the connection port 43 when viewed in the +Z direction. In this embodiment, a portion of the first groove portion 151B is disposed between the inlet 44a and the connection port 43, and another portion is disposed between the outlet 44b and the connection port 43. In this manner, the first groove portion 151B does not surround the connection port 43, but is provided between the inlet 44a and the outlet 44b and the connection port 43. Such a first groove portion 151B can retain liquid flowing toward the connection port 43, and exhibits the same effects as the first recess group 131 of the first embodiment. Furthermore, the second groove portion 152B has the same configuration as the second groove portion 152A of the above-described modified example 2, and provides the same effects as the second groove portion 152A of the modified example 2. Note that the first groove portion 151B is an example of a "first liquid holding portion," and the second groove portion 152B is an example of a "second liquid holding portion."

[0093] (Embodiment 2) Fig. 14 is a cross-sectional view of a liquid jet head according to embodiment 2. Fig. 15 is a plan view of the flow path structure according to embodiment 2 as viewed in the -Z direction. The same components as those in embodiment 1 are denoted by the same reference numerals, and redundant explanations will be omitted.

[0094] The flow path structure 200 of the first embodiment is not limited to a configuration in which a plurality of first flow path members 201, second flow path members 202, and seal members 203 are stacked in the Z-axis direction, and the supply flow paths 400 and the recovery flow paths 410 are formed in all of the members. In other words, the supply flow paths 400 and the recovery flow paths 410 may not be formed in some of the members. The flow path structure 200 of the present embodiment is configured by stacking the first flow path members 201 and the second flow path members 202, and the supply flow paths 400 and the recovery flow paths 410 are formed in the first flow path member 201, while the supply flow paths 400 and the recovery flow paths 410 are not formed in the second flow path member 202.

[0095] Specifically, protrusions 207A protruding in the +Z direction are provided on the surface on the +Z direction side of the third member 201c of the first flow path member 201. In this embodiment, four protrusions 207A are provided corresponding to the four supply flow paths 400, and four protrusions 207A are provided corresponding to the four recovery flow paths 410. Four second supply flow paths 402 and four second recovery flow paths 412 are provided inside each protrusion 207A.

[0096] The supply channel 400 includes a first supply channel 401 formed in the first member 201a and the second member 201b, and a second supply channel 402 formed inside the protrusion 207A. The recovery channel 410 includes a first recovery channel 411 formed in the first member 201a and the second member 201b, and a second recovery channel 412 formed in the protrusion 207A.

[0097] The second flow path member 202 is provided with eight protrusion insertion holes 208 penetrating in the Z-axis direction, corresponding to the four inlets 44a and the four outlets 44b. The protrusions 207A are inserted through the protrusion insertion holes 214 of the relay substrate 210 to the +Z direction side of the relay substrate 210, and further inserted through the protrusion insertion holes 208 of the second flow path member 202 to the +Z direction side of the second flow path member 202, and are exposed inside the accommodation portion 230. The surface of the protrusion 207A on the +Z direction side is bonded to the upper surface 40a of the head chip 8 via a sealing member or adhesive (not shown). By bonding the protrusions 207A to the upper surface 40a, the supply flow path 400 or the recovery flow path 410 of the flow path structure 200 is connected to the inlets 44a or the outlets 44b of each head chip 8. As described above, the flow path structure 200 of this embodiment is formed by stacking a plurality of first flow path members 201 and second flow path members 202, but the second flow path member 202, which is the member on the head chip 8 side, does not have a supply flow path 400 or a recovery flow path 410 through which liquid flows.

[0098] Furthermore, a third recess group 133 (see FIG. 15 ) is provided on a flow path connection surface 231 of the flow path structure 200 facing the +Z direction. When there are multiple surfaces of different heights in the Z-axis direction on a surface facing the +Z direction of a member located furthest in the +Z direction of the flow path structure 200, the "flow path connection surface" of the flow path structure 200 refers to the surface at the height where the surface area is largest among the multiple surfaces. For example, the surface facing the +Z direction of the second flow path member 202, which is the member located furthest in the +Z direction of the flow path structure 200, may have steps formed by recesses, protrusions, etc., but the "flow path connection surface" refers to the surface facing the +Z direction of the portion with the largest surface area among the surfaces of different heights in the Z-axis direction, including these recesses and protrusions. In this embodiment, the bottom surface of the accommodation portion 230 facing the +Z direction of the second flow path member 202 is formed as a flat surface without any steps, and this bottom surface serves as the flow path connection surface 231.

[0099] The third recess group 133 has a configuration capable of retaining liquid that leaks when the flow path connection between the head chip 8 and the flow path structure 200 is released. In this embodiment, the third recess group 133 includes a plurality of recesses 140 recessed in the -Z direction with respect to the flow path connection surface, and a first groove portion 151 having a rectangular frame shape along the flow path connection surface 231 so as to surround the first wiring insertion hole 205 as viewed in the -Z direction. Furthermore, at least a portion of the third recess group 133 is disposed between the protrusion insertion hole 208 and the first wiring insertion hole 205 as viewed in the -Z direction. In this embodiment, as shown in FIG. 15 , two first wiring insertion holes 205 are provided in the second flow path member 202, and two protrusion insertion holes 208 are provided on the +Y direction side and the -Y direction side for each first wiring insertion hole 205. A portion of the third recess group 133, i.e., several recesses 140 and a portion of the first groove portion 151 connecting those recesses 140, is arranged between the protrusion insertion hole 208 on the -Y direction side and the first wiring insertion hole 205, and between the protrusion insertion hole 208 on the +Y direction side and the first wiring insertion hole 205.

[0100] In this way, the flow path connection surface 231 of the flow path structure 200 is provided with the third recessed portion group 133 that can retain liquid that leaks when the flow path connection is released. Portions of the flow path connection surface 231 where the third recessed portion group 133 is not provided serve as liquid non-retaining portions that do not retain leaked liquid. Not retaining leaked liquid means that the liquid non-retaining portions are less likely to retain liquid than the third recessed portion group 133. In this embodiment, the liquid non-retaining portions are part of the flow path connection surface 231 and are planar, and therefore are less likely to retain liquid than the third recessed portion 133 that has the recesses 140. Of course, the liquid non-retaining portions are not limited to being planar, and may be inclined, for example, so that liquid flows toward the third recessed portion group 133.

[0101] The plurality of recesses 140 constituting the third recess group 133 includes adjacent first recesses 141 and second recesses 142. That is, of any two adjacent recesses 140 among the plurality of recesses 140, one is the first recess 141 and the other is the second recess 142. The third recess group 133 is formed by connecting any two adjacent recesses among the plurality of recesses 140, that is, the first recess 141 and the second recess 142, by a part of the first groove portion 151. The specific shapes and arrangements of the recesses 140 and the first groove portion 151 in this embodiment are the same as those in the first embodiment, and therefore detailed description thereof will be omitted.

[0102] 16 is a cross-sectional view of the liquid jet head 2 when the flow path connection between the head chip 8 and the flow path structure 200 has been released. In this embodiment, the flow path connection is released by reversing the Z axis direction from that of the liquid jet head 2 of Embodiment 1. That is, by removing the head chip 8 and the flow path structure 200 with the ejection surface 20a facing in the -Z direction, the connection between the supply flow path 400 and the inlet 44a is released, and the connection between the recovery flow path 410 and the outlet 44b is released.

[0103] When the liquid jet head 2 is disassembled into the flow path structure 200 and the head chip 8 with the ejection surface 20a of the nozzle plate 20 facing vertically upward, i.e., facing the -Z direction, there is a risk that the liquid 500 leaking from the supply flow path 400, the recovery flow path 410, the inlet 44a, or the outlet 44b may adhere to the flow path connecting surface 231. However, by providing the third recess group 133, the liquid 500 adhering to the flow path connecting surface 231 is retained within the third recess group 133. Such a third recess group 133 can prevent the liquid 500 adhering to the flow path connecting surface 231 from penetrating into the wiring member 110 or the relay substrate 210 through the first wiring insertion hole 205. Therefore, it is possible to prevent the liquid 500 that has entered the first wiring insertion hole 205 from adhering to the wiring member 110 or the relay substrate 210 and causing electrical problems such as short-circuiting between wires.

[0104] As described above, the liquid jet head 2 of this embodiment includes the head chip 8 and the flow path structure 200, and the flow path structure 200 has the protrusions 207A for liquid-tight connection with the supply flow path 400 and the recovery flow path 410, and also has the flow path connection surface 231. The flow path connection surface 231 is provided with the third recess group 133 that can hold any liquid that leaks when the flow path connection between the head chip 8 and the flow path structure 200 is released, and a liquid non-holding portion that does not hold any leaked liquid.

[0105] According to such a liquid jet head 2, when the liquid jet head 2 is disassembled into the head chip 8 and the flow path structure 200 as shown in FIG. 16 , the liquid 500 leaking from the supply flow path 400, the recovery flow path 410, the inlet 44a, or the outlet 44b can be retained in the third recess group 133, thereby preventing the liquid 500 from entering the first wire insertion hole 205. This prevents the liquid from adhering to the wiring member 110 or the relay substrate 210 around the first wire insertion hole 205 and causing electrical malfunctions such as short-circuiting between the wires. Since the liquid jet head 2 can be easily disassembled while preventing the liquid leaking when the flow path connection is released from entering the wiring member 110 or the relay substrate 210, for example, a defective head chip 8 can be easily replaced. By replacing defective parts of the liquid jet head 2, i.e., one or both of the head chip 8 and the flow path structure 200, the life of the liquid jet head 2 can be extended, and non-defective parts can be reused.

[0106] The head chip 8a is an example of a "head chip." The +Z direction is an example of a "first direction," and the -Z direction is an example of a "second direction." The supply channel 400 and the recovery channel 410 are examples of a "channel." The third recess group 133 is an example of a "fourth liquid holding portion." The protrusion 207A provided with the supply channel 400 or the recovery channel 410 is an example of a "channel connection portion." The channel connection portion of the channel structure includes a state in which it is disposed on the channel connection surface 231 when the channel connection surface 231 is viewed in a plan view in the -Z direction. That is, the channel connection portion may be formed on the first channel member 201 that is separate from the second channel member 202 on which the channel connection surface 231 is formed, as in the protrusion 207A of this embodiment. Of course, the channel connection portion may be formed on the second channel member 202 on which the channel connection surface 231 is formed.

[0107] In the liquid jet head 2 of this embodiment, several recesses 140 that are at least a part of the third recess group 133 and parts of the first grooves 151 that connect these recesses 140 are disposed between the protrusions 207A and the first wiring insertion holes 205 when viewed in the -Z direction. Liquid 500 that leaks when the head chip 8 and the flow path structure 200 are disconnected is likely to fall around the protrusions 207A. In this embodiment, at least a part of the third recess group 133 is disposed between the protrusions 207A and the first wiring insertion holes 205. This makes it possible to more effectively retain liquid in the third recess group 133, and more reliably prevent liquid from seeping into the wiring member 110 and the relay substrate 210 via the first wiring insertion holes 205.

[0108] In the liquid jet head 2 of this embodiment, the third recess group 133 is provided, when viewed in the +Z direction, so as to surround the first wiring insertion hole 205. Such a third recess group 133 can more reliably prevent the liquid 500 leaking to the flow path connection surface 231 from entering the wiring member 110 or the relay substrate 210 via the first wiring insertion hole 205.

[0109] In the liquid jet head 2 of this embodiment, the third recess group 133 includes a plurality of recesses 140 recessed in the −Z direction with respect to the flow path connecting surface 231, and a first groove portion 151 recessed in the −Z direction with respect to the flow path connecting surface 231 and extending along the flow path connecting surface 231. The plurality of recesses 140 includes adjacent first recesses 141 and second recesses 142, and the first recesses 141 and second recesses 142 are connected by a portion of the first groove portion 151. Since the third recess group 133 includes the plurality of recesses 140 and the first groove portion 151 connecting them, even if the liquid 500 concentrates and flows into some of the recesses 140 or some of the first groove portions 151, the liquid 500 is dispersed and held in the other recesses 140. Such a third recess group 133 can more reliably prevent the liquid 500 from entering the first wire insertion hole 205.

[0110] Furthermore, the liquid jet head 2 of the present embodiment may be provided with a liquid holding portion similar to those of Modifications 1 to 4 of Embodiment 1. That is, the first recess group 131A of Modification 1 may be provided on the flow path connecting surface 231 of the flow path structure 200 so as to surround the first wire insertion hole 205. Furthermore, the first groove portion 151A of Modification 2 may be provided on the flow path connecting surface 231 of the flow path structure 200 so as to surround the first wire insertion hole 205. Furthermore, the flow path connecting surface 231 of the flow path structure 200 may be provided with an inner region 161a of the first region 161 of Modification 3 so as to surround the first wire insertion hole 205, and an outer region 161b so as to surround the first wire insertion hole 205 and the protrusion insertion hole 208, with the second region 162 being defined between the inner region 161a and the outer region 161b. Furthermore, the first groove portion 151B of Modification 4 may be provided between the first wire insertion hole 205 and the protrusion insertion hole 208 on the flow path connecting surface 231 of the flow path structure 200. In any of the modifications, it is possible to prevent the liquid leaking into the liquid non-retaining portion of the flow path connecting surface 231 from entering the first wire insertion hole 205.

[0111] (Other embodiments) Although one embodiment of the present invention has been described above, the basic configuration of the present invention is not limited to the above.

[0112] In the above-described first embodiment, the first liquid holding portion was provided in the head chip 8, and in the second embodiment, the third liquid holding portion was provided in the flow path structure 200. Although not particularly shown, a liquid jet head may be provided with the head chip 8 provided with the first liquid holding portion and the flow path structure 200 provided with the third liquid holding portion. In a liquid jet head configured in this manner, even when the head chip 8 and the flow path structure 200 are disassembled with the ejection surface 20a of the liquid jet head facing either the +Z direction or the −Z direction, the liquid leaking to the upper surface 40a or the flow path connecting surface 231 can be prevented from entering the connection port 43 or the first wiring insertion hole 205, and electrical defects in the wiring member 110, the relay substrate 210, etc. can be prevented.

[0113] In the above-described embodiments and their modified examples 1 and 2, there is one first recess group 131, one first recess group 131A, and one first groove 151A, but the number of such groups is not limited. That is, a plurality of first recess groups 131, a plurality of first recess groups 131A, and a plurality of first grooves 151A may be nested to surround the connection port 43. Similarly, a plurality of second recess groups 132, a plurality of second recess groups 132A, a plurality of second grooves 152A, and a plurality of second grooves 152B may be nested to surround the connection port 43, the inlet port 44a, and the outlet port 44b. Furthermore, in modified example 4, there is one first groove 151B, but the number of such groups is not limited. That is, a plurality of first grooves 151B may be provided between the inlet port 44a and the outlet port 44b and the connection port 43.

[0114] In the above-described first embodiment and its modified examples 1, 2, and 4, a plurality of recesses 140 may be arranged between the first liquid holding portion and the second liquid holding portion on the upper surface 40a. This reduces the proportion of the upper surface 40a occupied by non-liquid holding portions, making it possible to increase the amount of ink that can be held on the upper surface 40a. Similarly, in the second embodiment, a plurality of recesses may be arranged on the flow path connecting surface 231, separate from the first liquid holding portion.

[0115] In each of the above-described embodiments, the first liquid holding portion and the second liquid holding portion have the same configuration. For example, in Embodiment 1, the first liquid holding portion and the second liquid holding portion both include a plurality of recesses and grooves. However, the first liquid holding portion and the second liquid holding portion may have different configurations. That is, any combination of the first liquid holding portion and the second liquid holding portion shown in Embodiment 1 and each of Modifications 1-4 may be provided on the upper surface 40a or the flow path connecting surface 231. For example, a first recess group 131 including recesses 140 and first grooves 151 as the first liquid level holding portion, and a second recess group 132A including only recesses 140 of Modification 1 as the second liquid level holding portion may be provided on the upper surface 40a or the flow path connecting surface 231.

[0116] In the above-described embodiment, a circulation type liquid jet head 2 is exemplified, which supplies liquid from the liquid storage section 3 and recovers liquid that is not ejected from the liquid jet head 2, but this is not limited to this, and the present invention can also be applied to a liquid jet head 2 that does not recover liquid.

[0117] In the above-described first embodiment, a thin-film piezoelectric actuator is used as the pressure generating means for generating a pressure change in the pressure chamber 12, but the present invention is not limited to this, and other types of piezoelectric actuators can be used, such as thick-film piezoelectric actuators formed by methods such as attaching green sheets, or longitudinal vibration piezoelectric actuators in which piezoelectric material and electrode-forming material are alternately laminated to expand and contract in the axial direction. Furthermore, the pressure generating means can be a so-called electrostatic actuator, which generates static electricity between a vibration plate and an electrode, deforms the vibration plate by electrostatic force, and ejects droplets from the nozzle opening.

[0118] Furthermore, in the above-described liquid ejection device 1, an example has been given in which the liquid ejection head 2 is mounted on a holder 6a and moves in the Y-axis direction, which is the main scanning direction, but this is not particularly limited to this, and the present invention can also be applied to, for example, a so-called line-type recording device in which the liquid ejection head 2 is fixed and printing is performed simply by moving a medium S, such as paper, in the X-axis direction.

[0119] Furthermore, the present invention is broadly intended for liquid jet heads in general, and can be applied to, for example, recording heads such as various ink jet recording heads used in image recording devices such as printers, color material jetting heads used in manufacturing color filters for liquid crystal displays and the like, electrode material jetting heads used in forming electrodes for organic EL displays, FEDs (field emission displays), and the like, and bioorganic material jetting heads used in manufacturing biochips.

[0120] (Addendum) From the above-described exemplary embodiments, the following configurations can be understood, for example.

[0121] A preferred embodiment of a liquid jet head according to a first aspect includes a head chip that ejects liquid in a first direction and a flow path structure disposed in a second direction opposite to the first direction. The head chip has a flow path connection portion for liquid-tightly connecting to a flow path in the flow path structure and an upper surface facing the second direction. The upper surface is provided with a first liquid holding portion capable of holding liquid leaked when the flow path connection between the head chip and the flow path structure is released, and a liquid non-holding portion that does not hold the leaked liquid. When the head chip and the flow path structure are disassembled, liquid leaked from the flow path or the flow path connection portion can be held in the first liquid holding portion, thereby preventing the liquid from entering the head chip. Therefore, the liquid jet head can be easily disassembled in a state where the leaked liquid is prevented from entering the head chip when the flow path connection is released. This allows, for example, a defective head chip to be easily replaced. The life of the liquid jet head can be extended by replacing defective parts of the liquid jet head, i.e., the head chip or the flow path structure, or by reusing non-defective parts.

[0122] In Aspect 2, which is a specific example of Aspect 1, the head chip has a flexible substrate, and the top surface is provided with an opening through which the flexible substrate is inserted. According to Aspect 2, liquid leaking onto the top surface is retained by the first liquid level retaining section, thereby reducing the amount of liquid seeping into the opening formed in the top surface and preventing damage to the electrical connection between the flexible substrate and the head chip.

[0123] In Aspect 3, which is a specific example of Aspect 2, at least a portion of the first liquid holding portion is disposed between the flow path connection portion and the opening when viewed in the first direction. Liquid that leaks when the head chip and the flow path structure are disconnected is likely to fall around the flow path connection portion. By disposing at least a portion of the first liquid holding portion between the flow path connection portion and the opening, the liquid can be more effectively held in the first liquid level holding portion, and liquid can be more reliably prevented from seeping into the head chip through the opening.

[0124] In Aspect 4, which is a specific example of Aspect 2, the first liquid holding portion is provided so as to surround the opening when viewed in the first direction, which more reliably prevents liquid leaking onto the upper surface from entering the head chip via the opening.

[0125] In Aspect 5, which is a specific example of Aspect 4, the upper surface is provided with a second liquid holding portion that is arranged along the outer edge of the upper surface when viewed in the first direction and is capable of holding the leaked liquid. This allows the liquid adhering to the upper surface to be held in the second liquid holding portion. This prevents the liquid adhering to the upper surface from flowing onto the side surface of the head chip, thereby preventing the side surface and ejection surface of the head chip from becoming soiled with liquid.

[0126] In aspect 6, which is a specific example of aspect 1, the first liquid holding portion includes at least one of a plurality of recesses recessed in the first direction relative to the upper surface, and a groove portion recessed in the first direction relative to the upper surface and extending along the upper surface.

[0127] In aspect 7, which is a specific example of aspect 6, the first liquid holding portion includes the multiple recesses and the groove portion, the multiple recesses include adjacent first recesses and second recesses, and the first recesses and the second recesses are connected by a portion of the groove portion.

[0128] In Aspect 8, which is a specific example of Aspect 1, the upper surface includes a first region and a second region that has lower liquid repellency than the first region, and the first liquid holding portion is the second region.

[0129] In aspect 9, which is a specific example of aspect 1, a second head chip is provided that sprays liquid in the first direction, the second head chip has a flow path connection portion for liquid-tight connection with a flow path in the flow path structure and has an upper surface facing the second direction, and a third liquid holding portion capable of holding the leaked liquid is provided on the upper surface of the second head chip.

[0130] In Aspect 10, which is a specific example of Aspect 1, the flow path structure has a flow path connection surface facing the first direction, and the flow path connection surface is provided with a fourth liquid holding portion capable of holding the leaked liquid when the flow path connection between the head chip and the flow path structure is released, and a liquid non-holding portion that does not hold the leaked liquid. This allows the liquid leaked from the flow path to be held in the fourth liquid holding portion of the flow path connection surface when the head chip and the flow path structure are disassembled, thereby preventing the liquid from entering electronic components, etc. Since the liquid jet head can be easily disassembled in a state where the leaked liquid is prevented from entering electronic components, etc. when the flow path connection is released, for example, a defective head chip can be easily replaced. The life of the liquid jet head can be extended by replacing a defective part of the liquid jet head, i.e., the head chip or the flow path structure, or the non-defective parts can be reused.

[0131] A liquid jet head according to an eleventh preferred embodiment includes a plurality of head chips that eject liquid in a first direction and a flow path structure arranged in a second direction opposite to the first direction. The flow path structure has a plurality of flow path connection portions for liquid-tightly connecting to flow paths in the plurality of head chips and a flow path connection surface facing the first direction. The flow path connection surface is provided with a fourth liquid holding portion that can hold liquid that leaks when the flow path connection between the head chip and the flow path structure is released, and a liquid non-holding portion that does not hold the leaked liquid. This allows liquid that leaks from the flow path to be held in the fourth liquid holding portion of the flow path connection surface when the head chip and the flow path structure are disassembled, thereby preventing the liquid from entering electronic components, etc. Since the liquid jet head can be easily disassembled while preventing the liquid that leaks when the flow path connection is released from entering electronic components, for example, a defective head chip can be easily replaced. Replacing a defective part of the liquid jet head, i.e., the head chip or the flow path structure, can extend the life of the liquid jet head, and reuse non-defective parts.

[0132] A liquid ejection device according to Aspect 12, which is a preferred aspect, includes the liquid ejection head according to any one of Aspects 1 to 11, and a liquid storage unit that supplies liquid to the liquid ejection head. This makes it possible to realize a liquid ejection device that can easily disassemble the liquid ejection head and extend the life of the liquid ejection head. [Explanation of symbols]

[0133] 1...liquid ejection device, 2...liquid ejection head, 3...liquid storage section, 8, 8a...head chip, 8b...head chip (second head chip), 10...pressure chamber substrate, 12...pressure chamber, 20...nozzle plate, 20a...ejection surface, 21...nozzle, 40...case member, 40a...upper surface, 43...connection port (opening), 44a...inlet (flow path connection section), 44b...outlet (flow path connection section), 50...diaphragm, 60...first electrode, 70...piezoelectric layer, 80...second electrode, 90...individual lead electrode, 110...wiring member (flexible substrate), 131, 131A...first recess group (first liquid holding section, third liquid liquid holding portion), 132, 132A...second recess group (second liquid holding portion), 133...third recess group (fourth liquid holding portion), 140...recess, 141...first recess, 142...second recess, 151, 151A, 151B...first groove (groove), 152A, 152B...second groove, 161...first region, 162...second region, 200...flow path structure, 207A...projection (flow path connecting portion), 208...projection insertion hole, 210...relay substrate, 214...projection insertion hole, 220...cover, 230...accommodating portion, 231...flow path connecting surface, 300...piezoelectric actuator, 400...supply flow path, 410...recovery flow path

Claims

1. a head tip that ejects liquid in a first direction; a flow path structure disposed in a second direction opposite to the first direction; Equipped with the head chip has a flow path connecting portion for liquid-tightly connecting to the flow path in the flow path structure and has an upper surface facing the second direction; a first liquid holding portion capable of holding a leaked liquid when a flow path connection between the head chip and the flow path structure is released, and a liquid non-holding portion not holding the leaked liquid are provided on the upper surface; A liquid jet head characterized by:

2. The head chip has a flexible substrate, An opening into which the flexible substrate is inserted is provided on the top surface. The liquid jet head according to claim 1 .

3. At least a portion of the first liquid holding portion is disposed between the flow path connecting portion and the opening when viewed in the first direction. The liquid jet head according to claim 2 .

4. the first liquid holding portion is provided so as to surround the opening when viewed in the first direction; The liquid jet head according to claim 2 .

5. a second liquid holding portion capable of holding the leaked liquid is provided on the upper surface, the second liquid holding portion being arranged along an outer edge of the upper surface when viewed in the first direction; The liquid jet head according to claim 4 .

6. the first liquid holding portion includes at least one of a plurality of recesses recessed in the first direction relative to the upper surface and a groove recessed in the first direction relative to the upper surface and extending along the upper surface; The liquid jet head according to claim 1 .

7. the first liquid holding portion includes the plurality of recesses and the groove portion, the plurality of recesses include a first recess and a second recess adjacent to each other, The first recess and the second recess are connected by a part of the groove. The liquid jet head according to claim 6 .

8. the upper surface includes a first region and a second region having lower liquid repellency than the first region; the first liquid holding portion is the second region; The liquid jet head according to claim 1 .

9. a second head tip configured to eject liquid in the first direction; the second head chip has a flow path connecting portion for liquid-tightly connecting to a flow path in the flow path structure, and the upper surface faces in the second direction; a third liquid holding portion capable of holding the leaked liquid is provided on the upper surface of the second head chip; The liquid jet head according to claim 1 .

10. the flow path structure has a flow path connection surface facing the first direction, the flow path connection surface is provided with a fourth liquid holding portion capable of holding the leaked liquid when the flow path connection between the head chip and the flow path structure is released, and a liquid non-holding portion that does not hold the leaked liquid. The liquid jet head according to claim 1 .

11. a plurality of head chips that eject liquid in a first direction; a flow path structure disposed in a second direction opposite to the first direction; Equipped with the flow path structure has a plurality of flow path connection portions for liquid-tightly connecting to the flow paths in the plurality of head chips and has a flow path connection surface facing the first direction, The flow path connection surface is provided with a fourth liquid holding portion capable of holding a leaked liquid when the flow path connection between the head chip and the flow path structure is released, and a liquid non-holding portion that does not hold the leaked liquid. A liquid jet head characterized by:

12. A liquid jet head according to any one of claims 1 to 11; a liquid reservoir that supplies liquid to the liquid jet head; A liquid ejection device comprising:

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