JP6714881B2 - Liquid ejecting head and liquid ejecting apparatus - Google Patents

Description

The present invention relates to a liquid ejecting head having a pressure absorbing member and a liquid ejecting apparatus.

As a liquid ejecting head, for example, a part of a pressure generating chamber that communicates with a nozzle opening for ejecting ink droplets is composed of a vibrating plate, and the vibrating plate is deformed by a piezoelectric element to pressurize the ink in the pressure generating chamber to form a nozzle. There is an inkjet recording head or the like that ejects ink droplets from an opening.
Further, there is known a head body in which a protective substrate is bonded onto a flow path forming substrate on which a piezoelectric element is formed. In order to connect the electrode of the piezoelectric element and the COF (Chip On Film) board which is the wiring board on which the drive circuit is mounted, a through hole is formed in the protective substrate, and the lead electrode is pulled out from the piezoelectric element to the through hole. The COF substrate is connected to the lead electrode in the through hole. Further, one surface of the reservoir portion is sealed with a sealing film that is a pressure absorbing member so that pressure fluctuations in the pressure generating chamber and the like are absorbed (see, for example, Patent Document 1).

JP, 2010-228265, A

The larger the area of the pressure absorbing member that seals the reservoir portion, the better the efficiency of absorbing pressure fluctuations in the pressure generating chamber and the like. In order to increase the area of the pressure absorbing member, it is necessary to widen the reservoir portion.
In the structure in which the through hole is formed in the protective substrate, the lead electrode is drawn out from the piezoelectric element to the through hole, and the lead electrode and the COF substrate are connected in the through hole, it is necessary to avoid the through hole and widen the reservoir portion. Therefore, it is necessary to expand the flow path forming substrate, the protective substrate, the vibration plate, and the like in the direction avoiding the through holes to form the reservoir portion, and it is difficult to obtain a small-sized liquid ejecting head with reduced cost.

The present invention has been made to solve at least one of the above problems, and can be realized as the following modes or application examples.

[Application example 1]
A liquid jet head in which a plurality of nozzle openings for jetting a liquid are arranged side by side, and a flow path forming substrate having a liquid supply path for supplying the liquid to a pressure generating chamber communicating with the nozzle openings; A piezoelectric element that is formed on a formation substrate and that changes the pressure of the pressure generating chamber; a piezoelectric element holding portion that protects the piezoelectric element; and a protective substrate that has a through hole that exposes a lead electrode drawn from the piezoelectric element; A drive circuit housed in the through hole and connected to the lead electrode, a reservoir forming substrate covering the through hole, the protective substrate on the through hole, and a reservoir partially formed on the reservoir forming substrate And a compliance substrate that seals the reservoir portion and absorbs pressure fluctuations of the reservoir portion by a pressure absorbing member.

According to this application example, since the reservoir portion is also formed on the through hole, the area of the pressure absorbing member of the compliance substrate can be increased, and the pressure fluctuation absorbing efficiency is improved. In addition, since a part of the reservoir portion is also formed on the through hole in the stacking direction of the flow path forming substrate, the protective substrate, and the reservoir forming substrate, avoiding the through hole and expanding these substrates to expand the reservoir. As compared with the case where the portion is formed, a small-sized liquid ejecting head with reduced cost can be obtained.

[Application example 2]
The liquid jet head according to the above, wherein a wiring substrate connected to the drive circuit is connected in a direction different from a direction in which the lead electrodes are connected.
In this application example, since the wiring board is connected to the drive circuit in a direction different from the direction in which the lead electrode pulled out from the piezoelectric element is connected to the drive circuit, A smaller liquid jet head can be obtained.

[Application example 3]
The liquid ejecting head according to claim 1, further comprising a heat conducting member that is in contact with the drive circuit and the reservoir forming substrate.
In this application example, the heat generated in the drive circuit escapes through the reservoir forming substrate, the characteristic of the piezoelectric element changes due to the heat generated in the drive circuit, the change in the capacity of the pressure generating chamber and the liquid supply passage, the flow passage forming substrate. The peeling between the substrates due to the difference in thermal expansion between the protective substrate, the reservoir forming substrate and the compliance substrate can be suppressed. Therefore, it is possible to obtain the liquid ejecting head in which the variation of the ejecting state of the liquid is small, the leakage of the liquid from between the substrates is suppressed, and the durability is improved.

[Application example 4]
A liquid ejecting apparatus comprising the liquid ejecting head described above.

According to this application example, a liquid ejecting apparatus that can achieve the above-described effects can be obtained.

FIG. 1 is a schematic perspective view showing an example of an inkjet recording device. FIG. 3 is a schematic perspective view of an inkjet recording head. FIG. 3 is an exploded perspective view showing a schematic configuration of an inkjet recording head. FIG. 3 is a sectional perspective view of the inkjet recording head taken along the line AA in FIG. 2. FIG. 3 is a cross-sectional perspective view of the inkjet recording head taken along the lines AA and BB in FIG. 2. FIG. 3 is an exploded partial perspective view showing the configuration of an inkjet recording head. (A) is a partial plan view of the ink jet recording head, (b) is a C-C sectional view in (a), (c) is a D-D partial sectional view in (a).

Hereinafter, embodiments will be described in detail with reference to the drawings. In each of the following drawings, the scale of each layer and each member is different from the actual scale in order to make each layer and each member recognizable.
FIG. 1 is a schematic perspective view showing an example of an inkjet recording apparatus 1000 as a liquid ejecting apparatus. The inkjet recording apparatus 1000 includes an inkjet recording head 1 as a liquid ejecting head.
In FIG. 1, an inkjet recording apparatus 1000 includes recording head units 1A and 1B. The recording head units 1A and 1B are removably provided with cartridges 2A and 2B constituting an ink supply means, and a carriage 3 having the recording head units 1A and 1B mounted thereon has a carriage shaft 5 attached to an apparatus body 4. Is provided so as to be movable in the axial direction.

The recording head units 1A and 1B eject, for example, a black ink composition and a color ink composition, respectively. Then, the driving force of the drive motor 6 is transmitted to the carriage 3 via a plurality of gears (not shown) and the timing belt 7, so that the carriage 3 carrying the recording head units 1A and 1B moves along the carriage shaft 5. .. On the other hand, a platen 8 is provided on the apparatus body 4 along the carriage shaft 5, and a recording sheet S, which is a recording medium such as paper fed by a feed roller (not shown) or the like, is conveyed on the platen 8. It is like this. In FIG. 1, the transport direction is indicated by a white arrow.

The recording head units 1A and 1B are provided with the inkjet recording head 1 at a position facing the recording sheet S. In the figure, the inkjet recording head 1 is located on the recording sheet S side of the recording head units 1A and 1B and is not directly shown.

FIG. 2 is a schematic perspective view showing the ink jet recording head 1 according to the embodiment.
The ink jet recording head 1 has a substantially rectangular parallelepiped shape. Flexible boards 210 as wiring boards are inserted through openings 220 provided at both ends in the longitudinal direction of one surface of the widest surface of the rectangular parallelepiped. The longitudinal direction is indicated by a white arrow in FIG. The conveyance direction of the recording sheet S shown in FIG. 1 and the longitudinal direction of the ink jet recording head 1 coincide with each other. Here, the coincidence includes a dimensional error that occurs during manufacturing and an error due to a shift in the transport direction that occurs during transport.

Two ink inlets 230 are provided in the middle of the surface in which the two flexible substrates 210 are inserted, and ink is supplied from the cartridges 2A and 2B shown in FIG.
3 is an exploded perspective view showing a schematic configuration of the ink jet recording head 1, FIG. 4 is a cross-sectional perspective view of the ink jet recording head 1 taken along the line AA in FIG. 2, and FIG. 3 is a cross-sectional perspective view taken along line AA and BB in FIG.

2 to 5, the inkjet recording head 1 includes a flow path forming substrate 10, a nozzle plate 20, a protective substrate 30, a reservoir forming substrate 35, a compliance substrate 40, a drive circuit 200, and a flexible substrate 210.
The flow channel forming substrate 10, the nozzle plate 20, and the protective substrate 30 are stacked so that the flow channel forming substrate 10 is sandwiched between the nozzle plate 20 and the protective substrate 30, and the reservoir forming substrate 35 is stacked on the protective substrate 30. Further, the compliance substrate 40 is stacked on the reservoir forming substrate 35.
The drive circuit 200 is arranged in the through hole 33 formed in the protective substrate 30 between the flow path forming substrate 10 and the reservoir forming substrate 35.

FIG. 6 is an exploded partial perspective view showing a more detailed configuration of the ink jet recording head 1, and the reservoir forming substrate 35 and the compliance substrate 40 are omitted. FIG. 7A is a partial plan view of the inkjet recording head 1, in which the reservoir forming substrate 35 and the compliance substrate 40 are omitted. 7B is a sectional view taken along line CC of the ink jet recording head 1 in FIG. 7A, and FIG. 7C is a sectional view taken along line DD of the ink jet recording head 1 in FIG. 7A. ..
The flow path forming substrate 10 is made of, for example, a silicon single crystal plate having a plane orientation (110). A plurality of pressure generating chambers 12 are formed in two rows 13 on the flow path forming substrate 10 by anisotropic etching. Here, the rows 13 are juxtaposed in the width direction (direction orthogonal to the longitudinal direction) of the inkjet recording head 1. The cross-sectional shape of the pressure generating chamber 12 in the width direction of the inkjet recording head 1 is trapezoidal, and the pressure generating chamber 12 is formed long in the width direction of the inkjet recording head 1.

Further, a communication portion 14 as a liquid supply path is formed in a region of the flow path forming substrate 10 on the outer side in the longitudinal direction of the pressure generation chamber 12, and the communication portion 14 and each pressure generation chamber 12 are connected to each pressure generation chamber. They are communicated with each other through an ink supply passage 15 provided as a liquid supply passage. The ink supply passage 15 is formed with a width narrower than that of the pressure generating chamber 12, and keeps the flow resistance of the ink flowing from the communicating portion 14 into the pressure generating chamber 12 constant.

Nozzle openings 21 communicating with the outside are formed in the nozzle plate 20 in the vicinity of the ends of the pressure generating chambers 12 opposite to the ink supply passage 15.
The nozzle plate 20 is made of glass ceramics, a silicon single crystal substrate, rust-free steel, or the like.
The flow path forming substrate 10 and the nozzle plate 20 are fixed to each other with an adhesive, a heat-welding film, or the like.

An elastic film 50 forming a vibrating plate is formed on the surface of the flow path forming substrate 10 that faces the surface to which the nozzle plate 20 is fixed. For example, the elastic film 50 is made of silicon dioxide obtained by thermally oxidizing the flow path forming substrate 10 in a diffusion furnace at about 1100°C.
An insulating film 55 made of an oxide film is formed on the elastic film 50 of the flow path forming substrate 10. For example, the insulator film 55 is made of zirconium oxide, and is obtained by forming a zirconium film by a sputtering method or the like and then thermally oxidizing the zirconium film in a diffusion furnace at 500° C. to 1200° C. Here, the elastic film 50 and the insulator film 55 form a diaphragm.

Further, on the insulator film 55, a lower electrode 60 made of a metal such as platinum (Pt) or a metal oxide such as strontium ruthenate (SrRuO), a piezoelectric layer 70 having a perovskite structure, and gold (Au). , The upper electrode 80 made of metal such as iridium (Ir) is formed, and constitutes the piezoelectric element 300. Here, the piezoelectric element 300 refers to a portion including the lower electrode 60, the piezoelectric layer 70, and the upper electrode 80.

For example, the lower electrode 60 is formed by forming a lower electrode film made of a metal oxide such as platinum (Pt), iridium (Ir), and strontium ruthenate (SrRuO) on the entire surface of the insulator film 55, and then patterning it into a predetermined shape. Obtained.
For example, the piezoelectric layer 70 and the upper electrode 80 can be formed by the following method.
First, a piezoelectric layer film made of a piezoelectric material is formed on the lower electrode 60 and the insulating film 55. As the piezoelectric material, a piezoelectric layer film made of lead zirconate titanate (PZT) can be used.
The method for producing the piezoelectric layer film is a so-called sol in which a so-called sol in which a metal organic substance is dissolved and dispersed in a catalyst is applied, dried, gelled, and further baked at a high temperature to obtain a piezoelectric layer film made of a metal oxide. -A gel method can be used.
The method is not limited to the sol-gel method, and for example, a MOD (Metal-Organic Decomposition) method or the like may be used. Furthermore, the method of manufacturing the piezoelectric layer film by the liquid phase method is not limited, and a method of manufacturing the piezoelectric layer film using vapor phase growth such as sputtering may be used.

Explaining the sol-gel method in detail, first, a sol (solution) containing a metal organic compound is applied. Next, the piezoelectric precursor film obtained by coating is heated to a predetermined temperature and dried for a certain time, and the solvent of the sol is evaporated to dry the piezoelectric precursor film. Further, the piezoelectric precursor film is degreased at a constant temperature for a predetermined time in an air atmosphere.
The degreasing referred to here is to remove the organic component of the sol film as NO ₂ , CO ₂ , H ₂ O or the like.

By repeating such coating, drying, and degreasing steps a predetermined number of times, for example, twice, a piezoelectric precursor film is formed to a predetermined thickness, and the piezoelectric precursor film is heat-treated in a diffusion furnace or the like. To crystallize to form a piezoelectric film. That is, by firing the piezoelectric precursor film, crystals grow and a piezoelectric film is formed.
The firing temperature is preferably about 650° C. to 850° C., for example, the piezoelectric precursor film is fired at about 700° C. for 30 minutes to form the piezoelectric film. The crystals of the piezoelectric film formed under such conditions are preferentially oriented in the (100) plane.
By repeating the above-mentioned steps of coating, drying, degreasing, and firing a plurality of times, a piezoelectric layer film having a predetermined thickness, which is a multilayer piezoelectric film, is formed.

As the material of the piezoelectric layer film, for example, a relaxor ferroelectric in which a metal such as niobium, nickel, magnesium, bismuth, or yttrium is added to a ferroelectric piezoelectric material such as lead zirconate titanate may be used. Good. Alternatively, a piezoelectric element made of a so-called lead-free piezoelectric material that does not contain lead in the piezoelectric material may be used.

After forming the piezoelectric layer film, for example, an upper electrode film made of gold (Au), iridium (Ir) or the like is formed on the entire surface of the piezoelectric layer film. The upper electrode film can be formed by a sputtering method, for example, DC or RF sputtering method.

The piezoelectric layer film and the upper electrode film are patterned in a region facing each pressure generating chamber 12 to form the piezoelectric element 300 including the lower electrode 60, the piezoelectric layer 70, and the upper electrode 80.

In general, one of the electrodes of the piezoelectric element 300 is used as a common electrode, and the other electrode and the piezoelectric layer 70 are patterned in each pressure generating chamber 12. Further, here, a portion which is composed of one of the patterned electrodes and the piezoelectric layer 70 and in which piezoelectric strain is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion.
In the embodiment, the lower electrode 60 is the common electrode of the piezoelectric element 300 and the upper electrode 80 is the individual electrode of the piezoelectric element 300. However, there is no problem in reversing this due to the driving circuit 200 and wiring. In any case, the piezoelectric active portion is formed for each pressure generating chamber 12. Further, here, the piezoelectric element 300 and the elastic film 50 and the insulating film 55 (vibration plate) that are displaced by the driving of the piezoelectric element 300 are collectively referred to as a piezoelectric actuator.

Further, a lead electrode 90 as a lead electrode made of, for example, gold (Au) is connected to the upper electrode 80 constituting each piezoelectric element 300 as described above, and the lead electrode 90 is used as the pressure generating chamber 12. To the region between the rows 13 of.

The lead electrode 90 forms a metal layer made of, for example, gold (Au) over the entire surface of the flow path forming substrate 10, and thereafter, the metal layer is piezoelectrically formed via a mask pattern (not shown) made of, for example, a resist. It is obtained by forming the lead electrode 90 by patterning each element 300.

The protective substrate 30 has a piezoelectric element holding portion 31 in a region facing the piezoelectric element 300, in a state where a space that does not hinder the movement of the piezoelectric element 300 is secured. Two piezoelectric element holding portions 31 are provided corresponding to the two columns 13 of each pressure generating chamber 12.
The protective substrate 30 is adhered by the adhesive 56 onto the flow path forming substrate 10 on which the piezoelectric element 300 is formed.
For the adhesion, the flow path forming substrate 10 on which the piezoelectric element 300 prepared separately from the protective substrate 30 and the protective substrate 30 are opposed to each other so that the piezoelectric element 300 fits in the piezoelectric element holding portion 31, and the adhesive 56 is used. To glue.
The bonding is performed by treating the bonding surface with a primer, transferring the adhesive 56 to the bonding surface of the protective substrate 30, bonding the flow path forming substrate 10 and the protective substrate 30, and temporarily bonding and curing.

In addition, in the embodiment, each piezoelectric element holding portion 31 is integrally provided in a region corresponding to the row 13 of each pressure generating chamber 12, but may be independently provided for each piezoelectric element 300. ..
Examples of the material of the protective substrate 30 include glass, ceramic materials, metals, resins, and the like, but it is more preferable that the material is substantially the same as the thermal expansion coefficient of the flow path forming substrate 10. Then, it is formed using a silicon single crystal substrate of the same material as the flow path forming substrate 10.

Further, the protective substrate 30 is provided with a reservoir portion 32 extending from a region corresponding to the communication portion 14 of the flow path forming substrate 10 to above the piezoelectric element holding portion 31. In the embodiment, the reservoir portion 32 is provided along the row 13 of the pressure generating chambers 12 and is communicated with the communication portion 14 of the flow path forming substrate 10 to be a common ink chamber for each pressure generating chamber 12. The manifold 100 is configured.

Further, the protective substrate 30 is formed in the thickness direction in a substantially central portion of the protective substrate 30 in a direction orthogonal to the longitudinal direction (indicated by a white arrow in the figure), that is, in a region where the rows 13 of the pressure generating chambers 12 face each other. A through hole 33 is provided so as to penetrate therethrough.
The through hole 33 can be formed by dry etching, for example. As the dry etching, for example, RIE (Reactive Ion Etching) can be used. For example, Fukahori RIE can be used. Fukahori RIE refers to reactive ion etching with a high aspect ratio (narrow and deep). The deep digging method usually uses a high-density plasma, and a method of cooling the sample to a low temperature, a method of using an etching technique called a Bosch process, or both of them.

The Bosch process is an etching method in which etching and etching sidewall protection are repeated, and etching with a high aspect ratio is possible.
The process repeats the following two processes. In some cases, there may be more steps.
Etching step: Isotropic etching is mainly performed using sulfur hexafluoride (SF ₆ ). Since there is a case where a protective film is attached to the bottom surface of the etching hole, it also works to remove the protective film on the bottom surface.
Protective step: Protect the sidewalls with a Teflon-based gas (such as C ₄ F ₈ ). By protecting the side wall, lateral etching is suppressed.
Since the protective film suppresses lateral etching, a thin and deep (high aspect ratio) hole can be dug. The angle of the sidewalls can be nearly vertical, or can be other angles by changing the process conditions.
A method using microwaves called ICP (inductively coupled plasma) RIE and ECR (Electron Cyclotron Resonance) RIE is mainly used as a method for generating high-density plasma.

The lead electrode 90 drawn out from the piezoelectric element 300 has at least its tip exposed at the bottom of the through hole 33.
The drive circuit 200 is housed in the through hole 33. The drive circuit 200 is placed on the tip of the lead electrode 90 exposed in the through hole 33, and the tip of the lead electrode 90 and a terminal (not shown) of the drive circuit 200 are connected.

The drive signal includes, for example, a drive system signal such as a drive power supply signal for driving the drive IC, and various control system signals such as a serial signal (SI), and the wiring includes a plurality of signals to which the respective signals are supplied. Composed of wiring.

A reservoir forming substrate 35 is stacked on the protective substrate 30, and a part of the reservoir portion 32 is formed on the through hole 33. Further, on the reservoir forming substrate 35, a girder 36 is formed over the longitudinal direction so as to cover the through hole 33 at a substantially central portion in a direction orthogonal to the longitudinal direction (the direction of the outlined arrow in the drawing). Here, the heat conducting member 400 is sandwiched between the girder 36 and the drive circuit 200, and is in contact with the girder 36 and the drive circuit 200.
As the heat conductive member 400, a resin such as an adhesive, silicon grease, grease in which silicon is highly filled with ceramic filler, or a heat dissipation sheet can be used.

On the reservoir forming substrate 35, a compliance substrate 40 including a sealing film 41 as a pressure absorbing member and a fixing plate 42 is joined. Here, the sealing film 41 is made of a material having low rigidity and flexibility (for example, a polyphenylene sulfide (PPS) film having a thickness of 6 μm), and one surface of the reservoir portion 32 is sealed by the sealing film 41. It has been stopped. The fixed plate 42 is formed of a hard material such as metal (for example, stainless steel (SUS) having a thickness of 30 μm). Since the region of the fixing plate 42 facing the manifold 100 is the opening 43 that is completely removed in the thickness direction, one surface of the manifold 100 is sealed with only the flexible sealing film 41. Has been done.

In the ink jet recording head 1, ink is taken in from the cartridges 2A and 2B, and the interior from the manifold 100 to the nozzle openings 21 is filled with ink. A voltage is applied between the lower electrode 60 and the upper electrode 80. By applying the voltage, the elastic film 50 and the piezoelectric layer 70 are flexibly deformed, the pressure inside each pressure generating chamber 12 is increased, and ink droplets are ejected from the nozzle openings 21.

The inkjet recording head 1 constitutes a part of a recording head unit having an ink flow path that communicates with an ink cartridge or the like serving as an ink supply unit, and is mounted on the inkjet recording apparatus 1000.

According to such an embodiment, there are the following effects.
(1) Since the reservoir portion 32 is also formed on the through hole 33, the area of the sealing film 41 of the compliance substrate 40 can be made large and the pressure fluctuation absorption efficiency can be improved.
In particular, when the cartridges 2A and 2B are connected to the ink jet recording head 1, it is possible to absorb large pressure fluctuations generated in the reservoir portion 32, the pressure generating chamber 12, the communication portion 14 and the ink supply passage 15.
Further, since a part of the reservoir portion 32 is also formed on the through hole 33 in the stacking direction of the flow path forming substrate 10, the protective substrate 30, and the reservoir forming substrate 35, avoid the through hole 33 and avoid these. Compared with the case where the substrate is expanded to form the reservoir portion 32, it is possible to obtain the small-sized inkjet recording head 1 at a reduced cost.

(2) Since the flexible substrate 210 is connected to the drive circuit 200 in a direction different from the direction in which the lead electrode 90 pulled out from the piezoelectric element 300 is connected to the drive circuit 200, the lead electrode pulled out from the piezoelectric element 300. A smaller inkjet recording head 1 can be obtained in the direction of 90.

(3) The heat generated in the drive circuit 200 escapes via the reservoir forming substrate 35, the characteristic change of the piezoelectric element 300 due to the heat generated in the drive circuit 200, the pressure generation chamber 12, the communicating portion 14, and the ink supply path 15 It is possible to suppress peeling between the substrates due to a change in capacity, a difference in thermal expansion among the flow path forming substrate 10, the protective substrate 30, the reservoir forming substrate 35, and the compliance substrate 40. Therefore, it is possible to obtain the ink jet recording head 1 in which the fluctuation of the ink ejection state is small, the leakage of the ink from between the substrates is suppressed, and the durability is improved.

(4) It is possible to obtain the ink jet recording apparatus 1000 that can achieve the above effects.

In the above-described embodiment, the ink jet recording head has been described as an example of the liquid ejecting head, but the present invention is widely applicable to all liquid ejecting heads, and is applicable to a liquid ejecting head that ejects a liquid other than ink. Of course, it can be applied.
Other liquid ejecting heads include, for example, various recording heads used in image recording devices such as printers, color material ejecting heads used in manufacturing color filters such as liquid crystal displays, organic EL displays, and FEDs (field emission displays). Examples include an electrode material ejection head used for forming electrodes, and a bio-organic substance ejection head used for biochip manufacturing.

1... Inkjet recording head as liquid ejecting head, 1A, 1B... Recording head unit, 2A, 2B... Cartridge, 3... Carriage, 4... Device body, 5... Carriage shaft, 6... Drive motor, 7... Timing belt, 8... Platen, 10... Flow path forming substrate, 12... Pressure generating chamber, 13... Row, 14... Communication part as liquid supply path, 15... Ink supply path as liquid supply path, 20... Nozzle plate, 21... Nozzle Opening, 30... Protective substrate, 31... Piezoelectric element holding part, 32... Reservoir part, 33... Through hole, 35... Reservoir forming substrate, 36... Girder, 40... Compliance substrate, 41... Sealing film as pressure absorbing member, 42... Fixing plate, 43... Opening part, 50... Elastic film, 55... Insulator film, 56... Adhesive, 60... Lower electrode, 70... Piezoelectric layer, 80... Upper electrode, 90... Lead electrode, 100... Manifold , 200... Driving circuit, 210... Flexible substrate as wiring board, 220... Opening, 230... Ink inlet, 300... Piezoelectric element, 400... Thermal conductive member, 1000... Ink jet recording apparatus.

Claims (3)

A flow path forming substrate having a liquid supply path for supplying the liquid to a pressure generating chamber communicating with a nozzle opening for ejecting the liquid,
A reservoir forming substrate in which a part of a reservoir portion that supplies the liquid to the plurality of liquid supply paths is formed;
A drive circuit between the flow channel forming substrate and the reservoir forming substrate in a direction in which the flow channel forming substrate and the reservoir forming substrate are stacked,
A piezoelectric element that is connected to the drive circuit and changes the pressure in the pressure generating chamber,
A pressure absorbing member that seals the reservoir portion and absorbs pressure fluctuations of the reservoir portion by bending at least a part ;
Equipped with
In the stacking direction of the flow path forming substrate and the reservoir forming substrate, there is a part of the reservoir part and a bending part of the pressure absorbing member at a position overlapping the drive circuit. Characteristic liquid jet head. The liquid jet head according to claim 1,
A part of the reservoir portion is formed on a protective substrate having a piezoelectric element holding portion that protects the piezoelectric element,
The liquid jet head, wherein the piezoelectric element includes a lower electrode, a piezoelectric layer, and an upper electrode. A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1 .

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