Liquid ejection head, liquid ejection device

Abstract

To provide a technique that can shorten the distance from a pressure chamber to a heating resistor, and can adjust the temperature of ink in the pressure chamber with good control in a liquid discharge head.SOLUTION: A liquid discharge head comprises: a pressure chamber substrate having a plurality of pressure chambers; a piezoelectric element which is laminated on the pressure chamber substrate, and comprises an individual electrode individually provided for each of the plurality of pressure chambers, a common electrode common to the plurality of pressure chambers, and a piezoelectric material which is provided between the individual electrode and the common electrode in a lamination direction of the piezoelectric element and applies a pressure to a liquid in the pressure chamber; a drive wiring which is electrically connected to the individual electrode and the common electrode, and applies a voltage for driving the piezoelectric material to the piezoelectric material; and a heating resistor which is formed from the same material as that of any one of the individual electrode, the common electrode and the drive wiring, and heats the liquid in the pressure chamber.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a liquid ejection head and a liquid ejection device.

Background Art

[0002] A liquid ejection head including a pressure chamber for ejecting a liquid and a heater for heating ink flowing inside the liquid ejection head is known (for example, Patent Document 1). In this liquid ejection head, the heater is a film heater in which a heating wire is sealed, and is provided on a side surface of a head case of the liquid ejection head.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the conventional technology, since the distance between the heater and the pressure chamber that greatly contributes to the ejection of the liquid is long, there is a limit to accurately adjusting the temperature of the liquid in the pressure chamber. Therefore, there is a desire to arrange the heater in the vicinity of the pressure chamber. However, when a film heater is provided in the vicinity of the pressure chamber of the liquid ejection head, there are problems such as an increase in the size of the liquid ejection head.

Means for Solving the Problems

[0005] The present disclosure can be realized in the following forms.

[0006] According to a first aspect of the present disclosure, a liquid ejection head is provided. The liquid ejection head includes a pressure chamber substrate having a plurality of pressure chambers, a piezoelectric element laminated on the pressure chamber substrate, an individual electrode provided individually for each of the plurality of pressure chambers, a common electrode provided commonly for the plurality of pressure chambers, and a piezoelectric body provided between the individual electrode and the common electrode in the lamination direction of the piezoelectric element for applying pressure to the liquid in the pressure chamber. The liquid ejection head further includes a drive wiring electrically connected to the individual electrode and the common electrode for applying a voltage for driving the piezoelectric body to the piezoelectric body, and a heating resistor formed of the same material as any one of the individual electrode, the common electrode, and the drive wiring for heating the liquid in the pressure chamber.

[0007] According to a second aspect of the present disclosure, a liquid ejection device is provided. The liquid ejection device includes the liquid ejection head according to the first aspect and a control unit that controls a liquid ejection operation from the liquid ejection head.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Modes for Carrying Out the Invention

[0009] A. First Embodiment: FIG. 1 is an explanatory diagram showing a schematic configuration of a liquid ejection device 500 including a liquid ejection head 510 as a first embodiment of the present disclosure. In the present embodiment, the liquid ejection device 500 is an inkjet printer that ejects ink, which is an example of a liquid, onto a printing paper P to form an image. Instead of the printing paper P, the liquid ejection device 500 may use any type of medium such as a resin film or a fabric as an ejection target for the ink. In FIG. 1 and each subsequent figure, X, Y, and Z represent three mutually orthogonal spatial axes. In this specification, the directions along these axes are also referred to as the X-axis direction, the Y-axis direction, and the Z-axis direction. When specifying a direction, the positive direction is denoted as "+", the negative direction is denoted as "-", and the positive and negative signs are used together in the direction notation. The direction in which the arrow in each figure points is the + direction, and the opposite direction is the - direction. In the present embodiment, the Z direction coincides with the vertical direction, the +Z direction indicates vertically downward, and the -Z direction indicates vertically upward. Further, when the positive and negative directions are not limited, the three X, Y, and Z are described as the X-axis, Y-axis, and Z-axis.

[0010] As shown in FIG. 1, the liquid ejection device 500 includes a liquid ejection head 510, an ink tank 550, a conveyance mechanism 560, a movement mechanism 570, and a control unit 580. The liquid ejection head 510 has a detection resistor 401 and a heating resistor 601, as will be described later. A plurality of nozzles are formed in the liquid ejection head 510. The liquid ejection head 510 ejects, for example, a total of four colors of ink, black, cyan, magenta, and yellow, in the +Z direction to form an image on the printing paper P. The liquid ejection head 510 is mounted on a carriage 572 and reciprocates in the main scanning direction as the carriage 572 moves. In the present embodiment, the main scanning direction is the +X direction and the -X direction. The liquid ejection head 510 may eject ink of any color, not limited to four colors, such as light cyan, light magenta, and white.

[0011] The ink tank 550 stores the ink discharged from the liquid ejection head 510. The ink tank 550 is connected to the liquid ejection head 510 by a resin tube 552, and the ink in the ink tank 550 is supplied to the liquid ejection head 510 via the tube 552. Instead of the ink tank 550, a bag-shaped liquid pack formed of a flexible film may be provided.

[0012] The conveyance mechanism 560 conveys the printing paper P in the sub-scanning direction. The sub-scanning direction is a direction intersecting the X-axis direction which is the main scanning direction, and in this embodiment, it is the +Y direction and the -Y direction. The conveyance mechanism 560 includes a conveyance rod 564 to which three conveyance rollers 562 are attached, and a conveyance motor 566 that rotationally drives the conveyance rod 564. When the conveyance motor 566 rotationally drives the conveyance rod 564, the printing paper P is conveyed in the +Y direction which is the sub-scanning direction. The number of the conveyance rollers 562 is not limited to three and may be any number. Also, a configuration in which a plurality of conveyance mechanisms 560 are provided may be adopted.

[0013] The movement mechanism 570 includes, in addition to the carriage 572, a conveyance belt 574, a movement motor 576, and a pulley 577. The carriage 572 mounts the liquid ejection head 510 in a state where ink can be ejected. The carriage 572 is fixed to the conveyance belt 574. The conveyance belt 574 is stretched between the movement motor 576 and the pulley 577. When the movement motor 576 rotationally drives, the conveyance belt 574 reciprocates in the main scanning direction. Thereby, the carriage 572 fixed to the conveyance belt 574 also reciprocates in the main scanning direction.

[0014] The control unit 580 controls the entire liquid ejection device 500. For example, the control unit 580 controls the reciprocating motion along the main scanning direction of the carriage 572, the conveyance motion along the sub-scanning direction of the printing paper P, and the ejection operation of the liquid ejection head 510. The control unit 580 heats the liquid in the pressure chamber 12 by the heating resistor 601 provided in the liquid ejection head 510. In the present embodiment, the control unit 580 further detects the temperature of the pressure chamber 12 by the detection resistor 401 provided in the liquid ejection head 510. As will be described later, the control unit 580 also functions as a drive control unit for the piezoelectric element 300. Thus, in the present embodiment, the control unit 580 detects the temperature of the pressure chamber 12 and adjusts the temperature of the pressure chamber 12 by heating. The control unit 580 outputs a drive signal based on the detected temperature of the pressure chamber 12 to the liquid ejection head 510 to drive the piezoelectric element 300, thereby controlling the ejection of ink onto the printing paper P. The control unit 580 may be composed of one or a plurality of processing circuits such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array) and one or a plurality of storage circuits such as a semiconductor memory. In the present embodiment, the control unit 580 stores in advance in the storage circuit the correspondence relationship between the electrical resistance value of the detection resistor 401 and the temperature.

[0015] FIG. 2 is an exploded perspective view showing the configuration of the liquid ejection head 510. FIG. 3 is an explanatory view showing the configuration of the liquid ejection head 510 in a plan view. In FIG. 3, the configuration around the pressure chamber substrate 10 in the liquid ejection head 510 is shown. In FIG. 3, for ease of understanding of the technology, the protective substrate 30 and the case member 40 are omitted. FIG. 4 is a cross-sectional view showing the position IV-IV of FIG. 3.

[0016] As shown in FIG. 2, the liquid ejection head 510 includes a pressure chamber substrate 10, a communication plate 15, a nozzle plate 20, a compliance substrate 45, a protection substrate 30, a case member 40, and a wiring substrate 120. Further, as shown in FIG. 3, it includes a piezoelectric element 300, and as shown in FIG. 4, it includes a diaphragm 50. The pressure chamber substrate 10, the communication plate 15, the nozzle plate 20, the compliance substrate 45, the diaphragm 50, the piezoelectric element 300, the protection substrate 30, and the case member 40 are laminated members, and by laminating them, the liquid ejection head 510 is formed. In the present disclosure, the direction in which the laminated members forming the liquid ejection head 510 are laminated is also referred to as the "lamination direction".

[0017] The pressure chamber substrate 10 is formed using, for example, a silicon substrate, a glass substrate, an SOI substrate, various ceramic substrates, or the like. As shown in FIG. 3, a plurality of pressure chambers 12 are arranged on the pressure chamber substrate 10 along a direction predetermined in the pressure chamber substrate 10. The direction in which the plurality of pressure chambers 12 are arranged is also referred to as the "arrangement direction". The pressure chamber 12 is formed in a rectangular shape in which the length in the X-axis direction is longer than the length in the Y-axis direction in a plan view. The shape of the pressure chamber 12 is not limited to a rectangular shape, and may be a parallelogram shape, a polygonal shape, a circular shape, an oval shape, or the like. The oval shape referred to here means a shape in which both ends in the longitudinal direction are semi-circular based on a rectangular shape, and includes a rounded rectangular shape, an elliptical shape, an egg shape, and the like.

[0018] In this embodiment, the plurality of pressure chambers 12 are arranged in two columns with the Y-axis direction as the arrangement direction. In the example of FIG. 3, on the pressure chamber substrate 10, two pressure chamber columns are formed: a first pressure chamber column L1 with the Y-axis direction as the arrangement direction and a second pressure chamber column L2 with the Y-axis direction as the arrangement direction. The second pressure chamber column L2 is arranged adjacent to the first pressure chamber column L1 in a direction intersecting the arrangement direction of the first pressure chamber column L1. The direction intersecting the arrangement direction is also referred to as the "intersecting direction". In the example of FIG. 3, the intersecting direction is the X-axis direction, and the second pressure chamber column L2 is adjacent to the first pressure chamber column L1 in the -X direction. The arrangement direction means the macroscopic arrangement direction of the plurality of pressure chambers 12. For example, even when the plurality of pressure chambers 12 are arranged alternately in the intersecting direction one by one and are arranged in a plurality along the Y-axis direction according to a so-called staggered arrangement, this Y-axis direction is included in the arrangement direction.

[0019] The plurality of pressure chambers 12 belonging to the first pressure chamber column L1 and the plurality of pressure chambers 12 belonging to the second pressure chamber column L2 are formed such that their positions in the arrangement direction coincide with each other, and are arranged adjacent to each other in the intersecting direction. In each pressure chamber column, the pressure chambers 12 adjacent to each other in the Y-axis direction are partitioned by the partition wall 11 shown in FIG. 6, as will be described later.

[0020] As shown in FIGS. 2 and 4, on the +Z direction side of the pressure chamber substrate 10, a communication plate 15, a nozzle plate 20, and a compliance substrate 45 are laminated in this order. The communication plate 15 is, for example, a flat member made of a silicon substrate, a glass substrate, an SOI substrate, various ceramic substrates, a metal substrate, or the like. Examples of the metal substrate include a stainless steel substrate. The communication plate 15 is provided with a nozzle communication path 16, a first manifold portion 17, a second manifold portion 18, and a supply communication path 19. It is preferable to use a material for the communication plate 15 having a coefficient of thermal expansion substantially the same as that of the pressure chamber substrate 10. Thereby, when the temperatures of the pressure chamber substrate 10 and the communication plate 15 change, warping of the pressure chamber substrate 10 and the communication plate 15 due to the difference in the coefficient of thermal expansion can be suppressed.

[0021] As shown in FIG. 4, the nozzle communication passage 16 is a passage that communicates the pressure chamber 12 and the nozzle 21. The first manifold portion 17 and the second manifold portion 18 function as a part of the manifold 100 that serves as a common liquid chamber in which a plurality of pressure chambers 12 communicate. The first manifold portion 17 is provided so as to penetrate the communication plate 15 in the Z-axis direction. Further, as shown in FIG. 4, the second manifold portion 18 is provided on the surface of the communication plate 15 on the +Z direction side without penetrating the communication plate 15 in the Z-axis direction.

[0022] The supply communication passage 19 is a passage that communicates with one end of the pressure chamber 12 in the X-axis direction. There are a plurality of supply communication passages 19, which are arranged side by side in the Y-axis direction. The supply communication passages 19 are provided individually for each of the pressure chambers 12. The supply communication passages 19 communicate the second manifold portion 18 and each pressure chamber 12 to supply the ink in the manifold 100 to each pressure chamber 12.

[0023] The nozzle plate 20 is provided on the side opposite to the pressure chamber substrate 10 with the communication plate 15 interposed therebetween, that is, on the surface of the communication plate 15 on the +Z direction side. The material of the nozzle plate 20 is not particularly limited, and for example, a silicon substrate, a glass substrate, an SOI substrate, various ceramic substrates, or a metal substrate can be used. Examples of the metal substrate include a stainless steel substrate. As the material of the nozzle plate 20, an organic substance such as a polyimide resin can also be used. However, it is preferable to use a material having substantially the same coefficient of thermal expansion as that of the communication plate 15 for the nozzle plate 20. Thereby, when the temperatures of the nozzle plate 20 and the communication plate 15 change, warping of the nozzle plate 20 and the communication plate 15 due to differences in the coefficient of thermal expansion can be suppressed.

[0024] A plurality of nozzles 21 are formed in the nozzle plate 20. Each nozzle 21 communicates with each pressure chamber 12 via the nozzle communication passage 16. The plurality of nozzles 21 are arranged along the arrangement direction of the pressure chambers 12, that is, in the Y-axis direction. Two nozzle rows in which these plurality of nozzles 21 are arranged in a row are provided in the nozzle plate 20. The two nozzle rows respectively correspond to the first pressure chamber row L1 and the second pressure chamber row L2.

[0025] As shown in FIGS. 2 and 4, the compliance substrate 45 is provided, together with the nozzle plate 20, on the side opposite to the pressure chamber substrate 10 across the communication plate 15, that is, on the +Z direction side surface of the communication plate 15. The compliance substrate 45 is provided around the nozzle plate 20 and covers the openings of the first manifold portion 17 and the second manifold portion 18 provided on the communication plate 15. In the present embodiment, the 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. As shown in FIG. 4, the region of the fixed substrate 47 facing the manifold 100 is an opening 48 that is completely removed in the thickness direction. For this reason, one surface of the manifold 100 is a compliance portion 49 sealed only by the sealing film 46.

[0026] As shown in FIG. 4, on the side opposite to the nozzle plate 20 and the like across the pressure chamber substrate 10, that is, on the -Z direction side surface of the pressure chamber substrate 10, a diaphragm 50 and a piezoelectric element 300 are laminated. The piezoelectric element 300 causes the diaphragm 50 to flex and deform, generating a pressure change in the ink in the pressure chamber 12. In FIG. 4, for ease of understanding of the technology, the configuration of the piezoelectric element 300 is shown in a simplified manner. The diaphragm 50 is provided in the +Z direction of the piezoelectric element 300, and the pressure chamber substrate 10 is provided in the +Z direction of the diaphragm 50.

[0027] As shown in FIG. 4, on the -Z direction side surface of the pressure chamber substrate 10, a protective substrate 30 having substantially the same size as the pressure chamber substrate 10 is further joined by an adhesive or the like. The protective substrate 30 has a holding portion 31 that is a space for protecting the piezoelectric element 300. The holding portion 31 is provided for each row of piezoelectric elements 300 arranged side by side in the Y-axis direction and is formed in two rows side by side in the X-axis direction. Further, the protective substrate 30 is provided with a through hole 32 penetrating in the Z-axis direction between the two holding portions 31 arranged side by side in the X-axis direction.

[0028] As shown in FIG. 4, a case member 40 is fixed on a protection substrate 30. The case member 40 forms a manifold 100 communicating with a plurality of pressure chambers 12 together with a communication plate 15. The case member 40 has substantially the same outer shape as the communication plate 15 in a plan view, is joined to the protection substrate 30, and is also joined to the communication plate 15.

[0029] The case member 40 has a housing portion 41, a supply port 44, a third manifold portion 42, and a connection port 43. The housing portion 41 is a space having a depth capable of housing the pressure chamber substrate 10 and the protection substrate 30. The third manifold portion 42 is formed at positions adjacent to both outer sides of the housing portion 41 in the X-axis direction in the case member 40. The manifold 100 is formed by connecting the third manifold portion 42 to a first manifold portion 17 and a second manifold portion 18 provided on the communication plate 15. The manifold 100 is continuously provided in the Y-axis direction. The supply port 44 communicates with the manifold 100 and supplies ink to each manifold 100. The connection port 43 is a through hole communicating with the through hole 32 of the protection substrate 30, and the wiring substrate 120 is inserted therethrough.

[0030] In the liquid ejection head 510 of the present embodiment, as shown in FIG. 1, ink from an ink tank 550 is taken in from the supply port 44, the internal flow path is filled with ink from the manifold 100 to the nozzles 21, and then a voltage based on a drive signal is applied to each piezoelectric element 300 corresponding to the plurality of pressure chambers 12. Thereby, the diaphragm 50 deflects and deforms together with the piezoelectric element 300, the pressure in each pressure chamber 12 increases, and ink droplets are ejected from each nozzle 21.

[0031] Using FIGS. 3 to 6, the configuration on the -Z direction side of the pressure chamber substrate 10 including the diaphragm 50 and the piezoelectric element 300 will be described. FIG. 5 is a cross-sectional view showing an enlarged view of the vicinity of the piezoelectric element 300. FIG. 6 is a cross-sectional view showing the position VI-VI of FIG. 3. The liquid ejection head 510 has, on the -Z direction side of the pressure chamber substrate 10, in addition to the diaphragm 50 and the piezoelectric element 300, an individual lead electrode 91, a common lead electrode 92, a measurement lead electrode 93, a detection resistor 401, and a heating resistor 601.

[0032] As shown in FIGS. 5 and 6, the diaphragm 50 includes an elastic film 51 made of silicon oxide provided on the pressure chamber substrate 10 side and an insulator film 52 made of a zirconium oxide film provided on the elastic film 51. The flow path formed in the pressure chamber substrate 10 such as the pressure chamber 12 is formed by anisotropically etching the pressure chamber substrate 10 from the +Z direction side surface, and the -Z direction side surface of the flow path such as the pressure chamber 12 is composed of the elastic film 51. The diaphragm 50 may be composed of, for example, either one of the elastic film 51 and the insulator film 52, and further, other films other than the elastic film 51 and the insulator film 52 may be included. Examples of the material of the other film include silicon and silicon nitride.

[0033] The piezoelectric element 300 is an example of a piezoelectric actuator that generates a pressure change in the ink in the pressure chamber 12. As shown in FIGS. 5 and 6, the piezoelectric element 300 has a first electrode 60, a piezoelectric body 70, and a second electrode 80. The first electrode 60, the piezoelectric body 70, and the second electrode 80 are laminated in order from the +Z direction side to the -Z direction side as shown in FIGS. 5 and 6. The piezoelectric body 70 is provided between the first electrode 60 and the second electrode 80 in the lamination direction in which the first electrode 60, the second electrode 80, and the piezoelectric body 70 are laminated, that is, the Z-axis direction.

[0034] The first electrode 60 and the second electrode 80 are both electrically connected to the wiring board 120. The first electrode 60 and the second electrode 80 apply a voltage corresponding to the drive signal supplied from the head circuit 121 mounted on the wiring board 120 to the piezoelectric body 70. Different drive voltages are supplied to the first electrode 60 according to the ink ejection amount, and a constant holding voltage is supplied to the second electrode 80 regardless of the ink ejection amount. The ink ejection amount is the required volume change amount of the pressure chamber 12. When a potential difference occurs between the first electrode 60 and the second electrode 80 due to the driving of the piezoelectric element 300, the piezoelectric body 70 deforms. Due to the deformation of the piezoelectric body 70, the diaphragm 50 deforms or vibrates, and the volume of the pressure chamber 12 changes. When the volume of the pressure chamber 12 changes, pressure is applied to the ink accommodated in the pressure chamber 12, and the ink is ejected from the nozzle 21 through the nozzle communication passage 16.

[0035] Among the piezoelectric elements 300, the portion where piezoelectric strain occurs in the piezoelectric body 70 when a voltage is applied between the first electrode 60 and the second electrode 80 is also called the active portion 310. On the other hand, the portion where no piezoelectric strain occurs in the piezoelectric body 70 is also called the non-active portion 320. That is, among the piezoelectric elements 300, the portion where the piezoelectric body 70 is sandwiched between the first electrode 60 and the second electrode 80 is the active portion 310, and the portion where the piezoelectric body 70 is not sandwiched between the first electrode 60 and the second electrode 80 is the non-active portion 320. When the piezoelectric element 300 is driven, the portion that actually displaces in the Z-axis direction is also called the flexible portion, and the portion that does not displace in the Z direction is also called the non-flexible portion. That is, among the piezoelectric elements 300, the portion facing the pressure chamber 12 in the Z-axis direction becomes the flexible portion, and the outer portion of the pressure chamber 12 becomes the non-flexible portion. The active portion 310 is also called the active part, and the non-active portion 320 is also called the non-active part.

[0036] The first electrode 60 is formed of a conductive material such as a metal such as platinum (Pt), iridium (Ir), gold (Au), titanium (Ti), or a conductive metal oxide such as indium tin oxide abbreviated as ITO. The first electrode 60 may be formed by laminating a plurality of materials such as platinum (Pt), iridium (Ir), gold (Au), and titanium (Ti). In the present embodiment, platinum (Pt) is used as the first electrode 60.

[0037] As shown in FIG. 3, the first electrode 60 is an individual electrode provided individually for a plurality of pressure chambers 12. The width of the first electrode 60 in the Y-axis direction is narrower than the width of the pressure chamber 12. That is, both ends of the first electrode 60 in the Y direction are located inside both ends of the pressure chamber 12 in the Y-axis direction. As shown in FIG. 5, the end 60a of the first electrode 60 in the +X direction and the end 60b in the -X direction are respectively disposed outside the pressure chamber 12. For example, in the first pressure chamber row, the end 60a of the first electrode 60 is disposed at a position on the +X direction side with respect to the end 12a of the pressure chamber 12 in the +X direction. The end 60b of the first electrode 60 is disposed at a position on the -X direction side with respect to the end 12b of the pressure chamber 12 in the -X direction.

[0038] As shown in FIG. 3, the piezoelectric body 70 has a predetermined width in the X-axis direction and is provided to extend along the arrangement direction of the pressure chambers 12, that is, the Y-axis direction. Examples of the piezoelectric body 70 include a perovskite-structured crystal film made of a ferroelectric ceramic material showing an electromechanical conversion action formed on the first electrode 60, that is, a so-called perovskite-type crystal. As the material of the piezoelectric body 70, for example, a ferroelectric piezoelectric material such as lead zirconate titanate (PZT), or a material obtained by adding a metal oxide such as niobium oxide, nickel oxide or magnesium oxide thereto can be used. Specifically, lead titanate (PbTiO3), lead zirconate titanate (Pb(Zr,Ti)O3), lead zirconate (PbZrO3), lanthanum lead titanate ((Pb,La),TiO3), lanthanum lead zirconate titanate ((Pb,La)(Zr,Ti)O3) or lead magnesium niobium zirconate titanate (Pb(Zr,Ti)(Mg,Nb)O3) and the like can be used. In the present embodiment, lead zirconate titanate (PZT) is used as the piezoelectric body 70.

[0039] The material of the piezoelectric body 70 is not limited to lead-based piezoelectric materials containing lead, and non-lead-based piezoelectric materials can also be used. Examples of non-lead-based piezoelectric materials include bismuth ferrite ((BiFeO3), abbreviated as "BFO"), barium titanate ((BaTiO3), abbreviated as "BT"), potassium sodium niobate ((K,Na)(NbO3), abbreviated as "KNN"), potassium sodium lithium niobate ((K,Na,Li)(NbO3)), potassium sodium lithium tantalum niobate ((K,Na,Li)(Nb,Ta)O3), bismuth potassium titanate ((Bi1 / 2K1 / 2)TiO3, abbreviated as "BKT"), bismuth sodium titanate ((Bi1 / 2Na1 / 2)TiO3, abbreviated as "BNT"), bismuth manganate (BiMnO3, abbreviated as "BM"), a composite oxide containing bismuth, potassium, titanium and iron and having a perovskite structure (x[(BixK1-x)TiO3]-(1-x)[BiFeO3], abbreviated as "BKT-BF"), a composite oxide containing bismuth, iron, barium and titanium and having a perovskite structure ((1-x)[BiFeO3]-x[BaTiO3], abbreviated as "BFO-BT"), and those obtained by adding metals such as manganese, cobalt and chromium thereto ((1-x)[Bi(Fe1-yMy)O3]-x[BaTiO3] (M is Mn, Co or Cr)), etc.

[0040] The thickness of the piezoelectric body 70 is formed, for example, to be about 1000 nanometers to 4000 nanometers. As shown in FIG. 5, the width of the piezoelectric body 70 in the X-axis direction is longer than the length in the X-axis direction which is the longitudinal direction of the pressure chamber 12. For this reason, on both sides of the pressure chamber 12 in the X-axis direction, the piezoelectric body 70 extends to the outside of the pressure chamber 12. In this way, since the piezoelectric body 70 extends to the outside of the pressure chamber 12 in the X-axis direction, the strength of the diaphragm 50 is improved. Therefore, when the active part 310 is driven to displace the piezoelectric element 300, it is possible to suppress the occurrence of cracks or the like in the diaphragm 50 and the piezoelectric element 300.

[0041] As shown in FIG. 5, the +X-direction end portion 70a of the piezoelectric body 70 is located on the +X-direction side outside the end portion 60a of the first electrode 60 in the first pressure chamber row. That is, the end portion 60a of the first electrode 60 is covered by the piezoelectric body 70. On the other hand, the -X-direction end portion 70b of the piezoelectric body 70 is located on the +X-direction side inside the end portion 60b of the first electrode 60, and the end portion 60b of the first electrode 60 is not covered by the piezoelectric body 70.

[0042] As shown in FIGS. 3 and 6, a groove portion 71, which is a portion thinner in thickness than other regions, is formed in the piezoelectric body 70. As shown in FIG. 6, the groove portion 71 is provided at a position corresponding to each partition wall 11. The groove portion 71 is formed by completely removing the piezoelectric body 70 in the Z-axis direction. The piezoelectric body 70 may be formed thinner than other portions on the bottom surface of the groove portion 71. The width of the groove portion 71 in the Y-axis direction is the same as or wider than the width of the partition wall 11 in the Y-axis direction. As shown in FIG. 3, the groove portion 71 has a substantially rectangular external shape in plan view. By providing the groove portion 71 in the piezoelectric body 70, the rigidity of the portion of the diaphragm 50 facing the Y-axis direction end of the pressure chamber 12, that is, the arm portion of the diaphragm 50, is suppressed, so that the piezoelectric element 300 can be displaced more favorably. The groove portion 71 is not limited to a rectangular shape, and may be a polygon with five or more sides, or may be a circular shape, an elliptical shape, or the like.

[0043] As shown in FIGS. 3, 5, and 6, the second electrode 80 is provided on the opposite side of the first electrode 60 with the piezoelectric body 70 interposed therebetween, that is, on the -Z direction side of the piezoelectric body 70. The second electrode 80 is provided in common for a plurality of pressure chambers 12 and is a common electrode common to a plurality of active portions 310. The material of the second electrode 80 is not particularly limited, but similar to the first electrode 60, for example, conductive materials such as metals such as platinum (Pt), iridium (Ir), gold (Au), titanium (Ti), and indium tin oxide abbreviated as ITO are used. Alternatively, a plurality of materials such as platinum (Pt), iridium (Ir), gold (Au), titanium (Ti), etc. may be laminated and formed. In the present embodiment, iridium (Ir) is used as the second electrode 80.

[0044] As shown in FIG. 3, the second electrode 80 has a predetermined width in the X-axis direction and extends along the arrangement direction of the pressure chambers 12, that is, in the Y-axis direction. As shown in FIG. 6, the second electrode 80 is also provided on the side surface of the groove portion 71 of the piezoelectric body 70 and on the insulator film 52 that is the bottom surface of the groove portion 71.

[0045] In the first pressure chamber row, as shown in FIG. 5, the +X-direction end portion 80a of the second electrode 80 is disposed outside, that is, on the +X-direction side, of the end portion 60a of the first electrode 60 covered by the piezoelectric body 70. The end portion 80a of the second electrode 80 is outside the end portion 12a of the pressure chamber 12 and is located outside the end portion 60a of the first electrode 60. In the present embodiment, the end portion 80a of the second electrode 80 substantially coincides with the end portion 70a of the piezoelectric body 70 in the X-axis direction. As a result, at the +X-direction end of the active portion 310, the boundary between the active portion 310 and the inactive portion 320 is defined by the end portion 60a of the first electrode 60.

[0046] As shown in FIG. 5, the -X-direction end portion 80b of the second electrode 80 is disposed on the -X-direction side that is outside the -X-direction end portion 12b of the pressure chamber 12 and on the +X-direction side that is inside the end portion 70b of the piezoelectric body 70. The end portion 70b of the piezoelectric body 70 is located inside on the +X-direction side of the end portion 60b of the first electrode 60. Therefore, the end portion 80b of the second electrode 80 is located on the piezoelectric body 70 on the +X-direction side of the end portion 60b of the first electrode 60. On the -X-direction side of the end portion 80b of the second electrode 80, there is a portion where the surface of the piezoelectric body 70 is exposed. Thus, since the end portion 80b of the second electrode 80 is disposed on the +X-direction side of the end portion 70b of the piezoelectric body 70 and the end portion 60b of the first electrode 60, at the -X-direction end of the active portion 310, the boundary between the active portion 310 and the inactive portion 320 is defined by the end portion 80b of the second electrode 80.

[0047] Outside the end portion 80b of the second electrode 80, a wiring portion 85 is provided which is in the same layer as the second electrode 80 but is electrically discontinuous from the second electrode 80. The wiring portion 85 is formed so as to extend from the vicinity of the end portion 70b of the piezoelectric body 70 to the end portion 60b of the first electrode 60 with a space from the end portion 80b of the second electrode 80. The wiring portion 85 is provided for each active portion 310. That is, a plurality of the wiring portions 85 are arranged at predetermined intervals along the Y-axis direction. The wiring portion 85 is preferably formed in the same layer as the second electrode 80. Thereby, the manufacturing process of the wiring portion 85 can be simplified and the cost can be reduced. However, the wiring portion 85 may be formed in a layer different from the second electrode 80.

[0048] As shown in FIG. 5, an individual lead electrode 91 is connected to the first electrode 60 which is an individual electrode, and a common lead electrode 92 which is a driving common electrode is electrically connected to the second electrode 80 which is a common electrode, respectively. The individual lead electrode 91 and the common lead electrode 92 function as driving wirings for applying a voltage for driving the piezoelectric body 70 to the piezoelectric body 70. In the present embodiment, the power supply circuit for supplying power to the piezoelectric body 70 via the driving wiring and the power supply circuit for supplying power to the heating resistor 601 and the detection resistor 401 are different circuits from each other. In the individual lead electrode 91 and the common lead electrode 92, a flexible wiring board 120 is electrically connected to an end portion opposite to the end portion connected to the piezoelectric element 300. A plurality of wirings for connecting to the control unit 580 and a power supply circuit (not shown) are formed on the wiring board 120. In the present embodiment, the wiring board 120 is constituted by, for example, an FPC (Flexible Printed Circuit). Note that, instead of the FPC, it may be constituted by an arbitrary substrate having flexibility such as an FFC (Flexible Flat Cable).

[0049] As shown in FIGS. 3 and 4, the individual lead electrode 91 and the common lead electrode 92 are extended so as to be exposed in the through hole 32 formed in the protective substrate 30, and are electrically connected to the wiring board 120 in the through hole 32. A head circuit 121 having a switching element is mounted on the wiring board 120.

[0050] The materials of the individual lead electrodes 91 and the common lead electrode 92 are conductive materials. For example, gold (Au), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), platinum (Pt), aluminum (Al), etc. can be used. In this embodiment, gold (Au) is used as the individual lead electrodes 91 and the common lead electrode 92. Also, the individual lead electrodes 91 and the common lead electrode 92 may have an adhesion layer that improves the adhesion with the first electrode 60, the second electrode 80, and the diaphragm 50.

[0051] The individual lead electrodes 91 and the common lead electrode 92 are formed in the same layer but are formed to be electrically discontinuous. Thereby, compared with the case where the individual lead electrodes 91 and the common lead electrode 92 are formed individually, the manufacturing process can be simplified and the cost can be reduced. The individual lead electrode 91 and the common lead electrode 92 may be formed in different layers.

[0052] The individual lead electrodes 91 are provided for each active part 310, that is, for each first electrode 60. As shown in FIG. 5, for example, in the first pressure chamber row L1, the individual lead electrode 91 is connected to the vicinity of the end 60b of the first electrode 60 via the wiring part 85 and is drawn out in the -X direction up to the diaphragm 50.

[0053] As shown in FIG. 3, for example, in the first pressure chamber row L1, the common lead electrode 92 is drawn out in the -X direction from above the second electrode 80 to above the diaphragm 50 at both ends in the Y-axis direction. The common lead electrode 92 has an extension part 92a and an extension part 92b. As shown in FIGS. 3 and 5, for example, in the first pressure chamber row, the extension part 92a extends along the Y-axis direction in the region corresponding to the end 12a of the pressure chamber 12, and the extension part 92b extends along the Y-axis direction in the region corresponding to the end 12b of the pressure chamber 12. The extension part 92a and the extension part 92b are continuously provided in the Y-axis direction for a plurality of active parts 310.

[0054] The extending portions 92a and 92b extend from the inside of the pressure chamber 12 to the outside of the pressure chamber 12 in the X-axis direction. In the present embodiment, the active portion 310 of the piezoelectric element 300 extends to the outside of the pressure chamber 12 at both ends in the X-axis direction of the pressure chamber 12, and the extending portions 92a and 92b extend to the outside of the pressure chamber 12 on the active portion 310.

[0055] As shown in FIG. 5, a heating resistor 601 is provided on the surface on the -Z direction side of the diaphragm 50, specifically, on the surface on the -Z direction side of the diaphragm 50. Specifically, the heating resistor 601 is located between the diaphragm 50 and the piezoelectric body 70 in the Z-axis direction and is covered by the piezoelectric body 70. The heating resistor 601 is a conductor wiring used to heat the inside of the pressure chamber 12. In the present embodiment, the heating resistor 601 heats the liquid in the pressure chamber 12 by utilizing the resistive heating generated by passing an electric current through the electrical resistance of a metal, semiconductor, or the like.

[0056] As the material of the heating resistor 601, various heating elements can be used. As the heating element, for example, metal heating elements such as gold (Au), platinum (Pt), iridium (Ir), aluminum (Al), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), etc. can be used. The heating resistor 601 may be formed of a non-metal heating element such as silicon carbide, molybdenum silicide, carbon, or the like. In the present embodiment, the heating resistor 601 is located at the same position as the first electrode 60 in the stacking direction, that is, in the same layer as the first electrode 60, and is formed so as to be electrically discontinuous from the first electrode 60. The material of the heating resistor 601 is the same platinum (Pt) as the first electrode 60. Thereby, compared with the case where the heating resistor 601 is formed separately from the first electrode 60, the manufacturing process can be simplified and the cost can be reduced. The heating resistor 601 may be formed in a layer different from the first electrode 60.

[0057] As shown in FIG. 3, a part of the heating resistor 601 is linearly formed along the first pressure chamber row L1, and is disposed on the +X direction side of the pressure chamber 12 included in the first pressure chamber row L1, that is, outside the liquid ejection head 510 in the intersecting direction. In the present embodiment, in other parts of the heating resistor 601, it is linearly formed along the second pressure chamber row L2, and is disposed on the -X direction side of the pressure chamber 12 included in the second pressure chamber row L2, that is, outside the liquid ejection head 510 in the intersecting direction. Thus, in the present embodiment, the heating resistor 601 is continuously formed outside the liquid ejection head 510 so as to surround the first pressure chamber row L1 and the second pressure chamber row L2.

[0058] FIG. 3 shows a heating lead electrode 94 including a heating lead electrode 94a and a heating lead electrode 94b. The heating lead electrode 94 functions as a connection portion that connects the heating resistor 601 and the wiring substrate 120. One end of the heating resistor 601 is connected to the heating lead electrode 94a, and the other end of the heating resistor 601 is connected to the heating lead electrode 94b. Thereby, the heating resistor 601 is electrically connected to the wiring substrate 120, and the control unit 580 can detect the electrical resistance value of the heating resistor 601. In the example of FIG. 3, the heating resistor 601 is linearly formed, but is not limited thereto. For example, it may be formed as a so-called meandering pattern that reciprocates a plurality of times in the vicinity of the first pressure chamber row L1 and the second pressure chamber row L2. By configuring in this way, the accuracy of temperature adjustment of the pressure chamber 12 can be increased.

[0059] In this embodiment, the heating lead electrode 94 is formed in the same layer as the individual lead electrode 91 and the common lead electrode 92 and is formed to be electrically discontinuous. The material of the heating lead electrode 94 is a conductive material, for example, gold (Au), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), platinum (Pt), aluminum (Al), etc. In this embodiment, gold (Au) is used as the heating lead electrode 94. The material of the heating lead electrode 94 is the same as that of the individual lead electrode 91 and the common lead electrode 92. The heating lead electrode 94 may have an adhesion layer that improves the adhesion with the heating resistor 601 and the diaphragm 50.

[0060] As shown in FIG. 5, in this embodiment, a detection resistor 401 is further provided on the surface of the diaphragm 50 on the -Z direction side. Specifically, the detection resistor 401 is located between the diaphragm 50 and the piezoelectric body 70 in the Z-axis direction and is covered by the piezoelectric body 70. The detection resistor 401 is a conductor wiring used to detect the temperature of the pressure chamber 12. In this embodiment, the detection resistor 401 detects the temperature by utilizing the characteristic that the electrical resistance value of a metal, semiconductor, etc. changes with temperature. When driving the piezoelectric element 300, the control unit 580 measures the electrical resistance value of the detection resistor 401 and detects the temperature of the pressure chamber 12 based on the correspondence between the electrical resistance value of the detection resistor 401 and the temperature.

[0061] The material of the detection resistor 401 is a material whose electrical resistance value has temperature dependence. For example, gold (Au), platinum (Pt), iridium (Ir), aluminum (Al), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), etc. can be used. Among these, platinum (Pt) can be preferably adopted as the material of the detection resistor 401 from the viewpoints that the change in electrical resistance due to temperature is large and the stability and accuracy are high. The electrical resistance value is an example of the measured value of the detection resistor to be measured. In the present embodiment, the detection resistor 401 is formed in the same layer as the heating resistor 601 and the first electrode 60 in the stacking direction, and is formed so as to be electrically discontinuous from the heating resistor 601 and the first electrode 60. The material of the detection resistor 401 is the same platinum (Pt) as that of the heating resistor 601 and the first electrode 60. Thereby, compared with the case where the detection resistor 401 is formed separately from the heating resistor 601 and the first electrode 60, the manufacturing process can be simplified and the cost can be reduced. The detection resistor 401 may be formed in a layer different from the heating resistor 601 and the first electrode 60.

[0062] As shown in FIG. 3, in the present embodiment, the detection resistor 401 is continuously formed so as to surround the first pressure chamber row L1 and the second pressure chamber row L2. FIG. 3 shows a measurement lead electrode 93 including a measurement lead electrode 93a and a measurement lead electrode 93b. The measurement lead electrode 93 functions as a connection portion that connects the detection resistor 401 and the wiring board 120. One end of the detection resistor 401 is connected to the measurement lead electrode 93a, and the other end of the detection resistor 401 is connected to the measurement lead electrode 93b. Thereby, the detection resistor 401 is electrically connected to the wiring board 120, and the control unit 580 can detect the electrical resistance value of the detection resistor 401. In the example of FIG. 3, the detection resistor 401 is formed linearly, but is not limited thereto. For example, it may be formed in a so-called meandering pattern that reciprocates a plurality of times in the vicinity of the first pressure chamber row L1 and the second pressure chamber row L2. By configuring in this way, the detection accuracy of the temperature of the pressure chamber 12 can be increased.

[0063] In this embodiment, the measurement lead electrode 93 is formed in the same layer as the individual lead electrode 91 and the common lead electrode 92 and is formed to be electrically discontinuous. The material of the measurement lead electrode 93 is a conductive material, for example, gold (Au), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), platinum (Pt), aluminum (Al), etc. In this embodiment, gold (Au) is used as the measurement lead electrode 93. The material of the measurement lead electrode 93 is the same as that of the individual lead electrode 91 and the common lead electrode 92. The measurement lead electrode 93 may have an adhesion layer that improves the adhesion to the detection resistor 401 and the diaphragm 50.

[0064] As shown in FIG. 3, a part of the detection resistor 401 is linearly formed along the arrangement direction of the pressure chambers 12 in the first pressure chamber row L1, and is located on the +X direction side of the pressure chambers 12 included in the first pressure chamber row L1, that is, outside the liquid ejection head 510 in the crossing direction. In this embodiment, in other parts of the detection resistor 401, it is linearly formed along the arrangement direction of the pressure chambers 12 in the second pressure chamber row L2, and is located on the -X direction side of the pressure chambers 12 included in the second pressure chamber row L2, that is, outside the liquid ejection head 510 in the crossing direction. Thus, in this embodiment, the detection resistor 401 is continuously formed outside the liquid ejection head 510 so as to surround the first pressure chamber row L1 and the second pressure chamber row L2. The detection resistor 401 is arranged inside the liquid ejection head 510 closer to the pressure chamber 12 than the heating resistor 601. By arranging the detection resistor 401 at a position closer to the pressure chamber 12, the detection of the temperature of the pressure chamber 12 by the detection resistor 401 is prioritized over the temperature adjustment of the pressure chamber 12 by the heating resistor 601, and the detection accuracy of the temperature of the pressure chamber 12 can be increased. Such a configuration is particularly effective when the liquid ejection head 510 includes the detection resistor 401 and the heating resistor 601 in the same layer because it is necessary to efficiently arrange the detection resistor 401 and the heating resistor 601.

[0065] As shown in FIG. 3, the heating resistor 601 is arranged outside the detection resistor 401 in the liquid ejection head 510 so as to surround the detection resistor 401. The wiring length of the heating resistor 601 connecting from the heating lead electrode 94a to the heating lead electrode 94b is longer than the wiring length of the detection resistor 401 connecting from the measurement lead electrode 93a to the measurement lead electrode 93b. Thereby, the electrical resistance of the heating resistor 601 becomes larger than the electrical resistance of the detection resistor 401, and heating can be performed more efficiently using the resistive heating of the heating resistor 601.

[0066] As shown in FIG. 5, in the present embodiment, although the thicknesses of the heating resistor 601 and the detection resistor 401 are the same, the width of the heating resistor 601 in the X-axis direction is formed to be smaller than the width of the detection resistor 401 in the X-axis direction. That is, in the present embodiment, the cross-sectional area of the heating resistor 601 is smaller than the cross-sectional area of the detection resistor 401. Thereby, the electrical resistance of the heating resistor 601 becomes larger than the electrical resistance of the detection resistor 401, and heating can be performed more efficiently using the resistive heating of the heating resistor 601. Such a configuration is particularly effective when the liquid ejection head 510 includes the detection resistor 401 and the heating resistor 601 in the same layer because it is necessary to arrange the detection resistor 401 and the heating resistor 601 efficiently.

[0067] As described above, according to the liquid ejection head 510 according to the first embodiment and the liquid ejection device 500 according to the first embodiment, the following effects can be obtained.

[0068] According to the liquid ejection head 510 of the present embodiment, a pressure chamber substrate 10 having a plurality of pressure chambers 12, a piezoelectric element 300 laminated on the pressure chamber substrate 10, an individual lead electrode 91 and a common lead electrode 92 that function as drive wirings for applying a voltage for driving the piezoelectric body 70 to the piezoelectric body 70, a piezoelectric element 300 including a first electrode 60 that is an individual electrode, a second electrode 80 that is a common electrode, and a piezoelectric body 70 for applying pressure to the liquid in the pressure chamber 12, and a heating resistor 601 for heating the liquid in the pressure chamber 12 are provided. The heating resistor 601 is formed of platinum (Pt) which is the same material as the first electrode 60 that is an individual electrode. According to the liquid ejection head 510 of the present embodiment, a heating resistor 601 for heating the liquid in the pressure chamber 12 is provided inside the liquid ejection head 510. For example, when the heating resistor is provided outside the liquid ejection head 510, the heat generated from the heating resistor diffuses, and there is a possibility that the heat transfer efficiency may decrease as compared with the case where the heating resistor is provided inside the liquid ejection head 510. In this case, there is a possibility that the liquid ejection device 500 may not be able to perform ejection control suitable for the temperature of the ink in the pressure chamber 12. In the present embodiment, the heating resistor 601 is provided by being laminated on a diaphragm 50 which is a component of the liquid ejection head 510. That is, the heating resistor 601 is provided inside the liquid ejection head 510. As a result, the liquid ejection head 510 can improve the heat transfer efficiency as compared with the case of heating the ink from the outside of the liquid ejection head 510. As a result, the liquid ejection device 500 can easily perform ejection control of the liquid ejection head 510 suitable for the temperature of the ink in the pressure chamber 12. According to the liquid ejection head 510 of the present embodiment, the distance between the pressure chamber 12 and the heating resistor 601 can be shortened as compared with a liquid ejection head having a heater outside, and the temperature of the ink in the pressure chamber 12 can be adjusted with good controllability. Further, by providing the heating resistor 601 inside the liquid ejection head 510, it is possible to suppress the liquid ejection head 510 from becoming large-sized.

[0069] According to the liquid ejection head 510 of the present embodiment, the heating resistor 601 is disposed at the same position in the stacking direction as the first electrode 60 which is an individual electrode, that is, in the same layer as the first electrode 60. Therefore, the heating resistor 601 can be formed in the same process as the process of forming the first electrode 60.

[0070] According to the liquid ejection head 510 of the present embodiment, the heating resistor 601 is disposed outside the liquid ejection head 510 in the crossing direction rather than the pressure chamber 12. Heat dissipation from the pressure chamber 12 to the outside of the liquid ejection head 510 can be reduced, and the temperature of the ink in the pressure chamber 12 can be efficiently adjusted.

[0071] The liquid ejection head 510 of the present embodiment further includes a detection resistor 401 for detecting the temperature in the pressure chamber 12, and the detection resistor 401 is formed of the same material as the first electrode 60 which is an individual electrode. For example, if the detection resistor is provided outside the liquid ejection head 510, the distance from the pressure chamber 12 becomes long, and the difference between the temperature measured by the detection resistor and the temperature in the pressure chamber 12 may be larger than that when the detection resistor is provided inside the liquid ejection head 510. In this case, there is a possibility that the liquid ejection device 500 may not be able to perform ejection control suitable for the temperature of the ink in the pressure chamber 12. In the present embodiment, the detection resistor 401 is provided by being laminated on the diaphragm 50 which is a component of the liquid ejection head 510. That is, the detection resistor 401 is provided inside the liquid ejection head 510. As a result, the liquid ejection head 510 can reduce the difference between the temperature detected by the detection resistor 401 and the temperature in the pressure chamber 12 as compared with the case of measuring the temperature outside the liquid ejection head 510. The liquid ejection device 500 can easily perform ejection control of the liquid ejection head 510 suitable for the temperature of the ink in the pressure chamber 12.

[0072] According to the liquid ejection head 510 of the present embodiment, the heating resistor 601 is disposed outside the liquid ejection head 510 rather than the detection resistor 401. By disposing the detection resistor 401 at a position closer to the pressure chamber 12, detection of the temperature of the pressure chamber 12 by the detection resistor 401 is prioritized over temperature adjustment of the pressure chamber 12 by the heating resistor 601, and the detection accuracy of the temperature of the pressure chamber 12 can be increased. Such a configuration is particularly effective when the liquid ejection head 510 includes the detection resistor 401 and the heating resistor 601 in the same layer because it is necessary to efficiently arrange the detection resistor 401 and the heating resistor 601.

[0073] According to the liquid ejection head 510 of the present embodiment, the cross-sectional area of the heating resistor 601 is smaller than the cross-sectional area of the detection resistor 401. Thereby, the electric resistance of the heating resistor 601 becomes larger than the electric resistance of the detection resistor 401, and heating can be performed more efficiently using the resistive heating of the heating resistor 601. Such a configuration is particularly effective when the liquid ejection head 510 includes the detection resistor 401 and the heating resistor 601 in the same layer because it is necessary to efficiently arrange the detection resistor 401 and the heating resistor 601.

[0074] According to the liquid ejection head 510 of the present embodiment, the length of the heating resistor 601 is longer than the length of the detection resistor 401. Thereby, the electric resistance of the heating resistor 601 becomes larger than the electric resistance of the detection resistor 401, and heating can be performed more efficiently using the resistive heating of the heating resistor 601.

[0075] According to the liquid ejection head 510 of the present embodiment, the power supply circuit for supplying power to the piezoelectric body 70 via the drive wiring and the power supply circuit for supplying power to the heating resistor 601 and the detection resistor 401 are different circuits from each other. Therefore, drive control of the piezoelectric element 300, heating of the liquid in the pressure chamber 12 by the heating resistor 601, and temperature detection of the pressure chamber 12 by the detection resistor 401 can be performed individually.

[0076] The liquid ejection device 500 includes a liquid ejection head 510 and a control unit 580 that controls the ink ejection operation from the liquid ejection head 510. According to this, a configuration capable of controlling the ejection operation of the liquid ejection head 510 can be easily realized.

[0077] B. Second Embodiment: With reference to FIG. 7, the heating resistor 651 included in the liquid ejection head 510 according to the second embodiment as one embodiment of the present disclosure will be described. FIG. 7 is an explanatory diagram showing the liquid ejection head according to the second embodiment. For parts common to the liquid ejection head 510 of the first embodiment, the same reference numerals are given and the description thereof is omitted.

[0078] In the first embodiment, an example was shown in which the heating resistor 601 is formed in the same layer as the first electrode 60 and is formed on the surface of the diaphragm 50 on the -Z direction side so as to be electrically discontinuous from the first electrode 60. On the other hand, in the present embodiment, the heating resistor 651 is different from the first embodiment in that it is provided on the surface of the piezoelectric body 70 on the -Z direction side as shown in FIG. 7. More specifically, the heating resistor 651 is formed in the same layer as the second electrode 80, which is a common electrode, and is formed on the surface of the piezoelectric body 70 on the -Z direction side so as to be electrically discontinuous from the second electrode 80. Thereby, compared with the case where the heating resistor 651 is formed separately from the second electrode 80, the manufacturing process can be simplified and the cost can be reduced.

[0079] In the present embodiment, the detection resistor 401 is formed in the same layer as the first electrode 60, which is an individual electrode, in the same manner as in the first embodiment. The material of the detection resistor 401 is the same platinum (Pt) as the first electrode 60. The second electrode 80 is made of iridium (Ir) and is formed of a material having a higher electrical resistance than the first electrode 60, which is an individual electrode. The first electrode 60 is formed of a material having a larger change rate of electrical resistance with respect to temperature change than the second electrode 80, which is a common electrode.

[0080] According to the liquid discharge head 510 of the present embodiment, the second electrode 80 is made of iridium (Ir) and is formed of a material having a higher electrical resistance than the first electrode 60 which is an individual electrode. On the other hand, the first electrode 60 is made of platinum (Pt) and is formed of a material having a larger change rate of electrical resistance with respect to temperature change than the second electrode 80 which is a common electrode. Therefore, a material suitable for the heating resistor 651 using resistance heating can be applied, and a material suitable for the detection resistor 401 using the temperature change of the electrical resistance value can be applied to the detection resistor 401. Since the heating resistor 651 is formed of the same material as the second electrode 80 which is a common electrode, it is easy to form in the same process as the second electrode 80 when forming the heating resistor 651.

[0081] According to the liquid discharge head 510 of the present embodiment, the detection resistor 401 is formed of the same material as the first electrode 60 which is an individual electrode. Therefore, it is easy to form in the same process as the first electrode 60 when forming the detection resistor 401.

[0082] C. Third Embodiment: With reference to FIG. 8, the detection resistor and the heating resistor included in the liquid discharge head 510 of the third embodiment as one embodiment of the present disclosure will be described. FIG. 8 is a plan view showing a liquid discharge head according to the third embodiment. Parts common to the liquid discharge head 510 of the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0083] In the first embodiment, an example was shown in which the detection resistor 401 and the heating resistor 601 are continuously formed outside the liquid ejection head 510 so as to surround the first pressure chamber row L1 and the second pressure chamber row L2. On the other hand, the liquid ejection head 510 of the present embodiment is different in that, as shown in FIG. 8, the detection resistor and the heating resistor include a plurality of detection resistors and heating resistors corresponding to each of the plurality of pressure chamber rows. According to this, the liquid ejection head 510 can detect the temperatures of the plurality of pressure chambers 12 separately for the plurality of pressure chamber rows, and can heat the liquid in the plurality of pressure chambers 12 separately for the plurality of pressure chamber rows. Note that such a configuration is not limited to both the detection resistor and the heating resistor, and only one of them may be provided.

[0084] As shown in FIG. 8, the liquid ejection head 510 includes a first detection resistor 402 and a first heating resistor 602. The first detection resistor 402 is disposed outside the liquid ejection head 510 relative to the first pressure chamber row L1, and is arranged along the Y-axis direction, which is the arrangement direction of each pressure chamber 12 included in the first pressure chamber row L1. The first heating resistor 602 is disposed outside the liquid ejection head 510 relative to the first detection resistor 402, and is arranged along the Y-axis direction, which is the arrangement direction of each pressure chamber 12 included in the first pressure chamber row L1. The first detection resistor 402 detects the temperature of the ink in the pressure chamber 12 included in the first pressure chamber row L1, and the first heating resistor 602 heats the ink in the pressure chamber 12 included in the first pressure chamber row L1. Also, as shown in FIG. 8, the liquid ejection head 510 includes a second detection resistor 403 and a second heating resistor 603. The second detection resistor 403 is disposed outside the liquid ejection head 510 relative to the second pressure chamber row L2, and is arranged along the Y-axis direction, which is the arrangement direction of each pressure chamber 12 included in the second pressure chamber row L2. The second heating resistor 603 is disposed outside the liquid ejection head 510 relative to the second detection resistor 403, and is arranged along the Y-axis direction, which is the arrangement direction of each pressure chamber 12 included in the second pressure chamber row L2. The second detection resistor 403 detects the temperature of the ink in the pressure chamber 12 included in the second pressure chamber row L2, and the second heating resistor 603 heats the ink in the pressure chamber 12 included in the second pressure chamber row L2. The measurement lead electrode 93 includes, in addition to the measurement lead electrode 93a and the measurement lead electrode 93b, further a measurement lead electrode 93c and a measurement lead electrode 93d. The heating lead electrode 94 includes, in addition to the heating lead electrode 94a and the heating lead electrode 94b, further a heating lead electrode 94c and a heating lead electrode 94d.

[0085] The first heating resistor 602 is continuous. One end of the first heating resistor 602 is connected to the heating lead electrode 94a, and the other end of the first heating resistor 602 is connected to the heating lead electrode 94c. The second heating resistor 603 is continuous. One end of the second heating resistor 603 is connected to the heating lead electrode 94b, and the other end of the second heating resistor 603 is connected to the heating lead electrode 94d. Thereby, the first heating resistor 602 is electrically connected to the wiring board 120, and the control unit 580 can apply a voltage to the first heating resistor 602. Also, the second heating resistor 603 is electrically connected to the wiring board 120, and the control unit 580 can apply a voltage to the second heating resistor 603.

[0086] The first detection resistor 402 is continuous. One end of the first detection resistor 402 is connected to the measurement lead electrode 93a, and the other end of the first detection resistor 402 is connected to the measurement lead electrode 93c. The second detection resistor 403 is continuous. One end of the second detection resistor 403 is connected to the measurement lead electrode 93b, and the other end of the second detection resistor 403 is connected to the measurement lead electrode 93d. Thereby, the first detection resistor 402 is electrically connected to the wiring board 120, and the control unit 580 can measure the electrical resistance value of the first detection resistor 402. Also, the second detection resistor 403 is electrically connected to the wiring board 120, and the control unit 580 can measure the electrical resistance value of the second detection resistor 403.

[0087] According to the liquid ejection head 510 of the present embodiment, the temperature of the ink in the pressure chamber 12 included in the first pressure chamber row L1 and the temperature of the ink in the pressure chamber 12 included in the second pressure chamber row L2 can be individually heated and temperature-adjusted. Even when the temperature of the ink is different for each pressure chamber row, the temperature of the ink can be individually adjusted to an appropriate temperature. The liquid ejection device 500 can more easily perform ejection control of the liquid ejection head 510 suitable for the temperature of the ink in the pressure chamber 12.

[0088] According to the liquid ejection head 510 of the present embodiment, when the temperature of the ink in the pressure chamber 12 included in the first pressure chamber row L1 is different from the temperature of the ink in the pressure chamber 12 constituting the second pressure chamber row L2, the piezoelectric element 300 corresponding to the temperature of the ink in the pressure chamber 12 constituting each pressure chamber row can be driven. Further, according to this, the liquid ejection device 500 can more easily perform ejection control of the liquid ejection head 510 suitable for the temperature of the ink in the pressure chamber 12.

[0089] D. Fourth Embodiment: With reference to FIG. 9, the detection resistor and the heating resistor provided in the liquid ejection head 510 of the fourth embodiment as one embodiment of the present disclosure will be described. FIG. 9 is a plan view showing the liquid ejection head according to the fourth embodiment. Parts common to the liquid ejection head 510 of the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0090] In the first embodiment, an example is shown in which the detection resistor 401 and the heating resistor 601 are continuously formed outside the liquid ejection head 510 so as to surround the first pressure chamber row L1 and the second pressure chamber row L2. On the other hand, the liquid ejection head 510 of the present embodiment is different in that the detection resistor and the heating resistor include a plurality of detection resistors and heating resistors corresponding to each of a plurality of pressure chamber groups, as shown in FIG. 9. According to this, the liquid ejection head 510 can detect the temperatures of the plurality of pressure chambers 12 by dividing them into a plurality of pressure chamber groups, and can heat the liquids in the plurality of pressure chambers 12 by dividing them into a plurality of pressure chamber groups. Note that such a configuration is not limited to both the detection resistor and the heating resistor, and only one of them may be provided.

[0091] As shown in Fig. 9, in the Y-axis direction which is the arrangement direction of the first pressure chamber row L1, a pressure chamber group including a plurality of pressure chambers 12 located on the -Y direction side which is one side from the center is also called the first pressure chamber group G1, and a pressure chamber group including a plurality of pressure chambers 12 located on the +Y direction side which is the other side from the center is also called the second pressure chamber group G2. In the Y-axis direction which is the arrangement direction of the second pressure chamber row L2, a pressure chamber group including a plurality of pressure chambers 12 located on the -Y direction side which is one side from the center is called the third pressure chamber group G3, and a pressure chamber group including a plurality of pressure chambers 12 located on the +Y direction side which is the other side from the center is called the fourth pressure chamber group G4.

[0092] As shown in Fig. 9, the liquid ejection head 510 includes a third detection resistor 406 arranged along the Y-axis direction which is the arrangement direction of each pressure chamber 12 included in the first pressure chamber group G1, outside the liquid ejection head 510 with respect to the first pressure chamber group G1, and a third heating resistor 606 arranged along the Y-axis direction which is the arrangement direction of each pressure chamber 12 included in the first pressure chamber group G1, outside the liquid ejection head 510 with respect to the third detection resistor 406. The third detection resistor 406 detects the temperature of the ink in the pressure chamber 12 included in the first pressure chamber group G1, and the third heating resistor 606 heats the ink in the pressure chamber 12 included in the first pressure chamber group G1.

[0093] The liquid ejection head 510 includes a fourth detection resistor 407 arranged along the Y-axis direction which is the arrangement direction of each pressure chamber 12 included in the second pressure chamber group G2, outside the liquid ejection head 510 with respect to the second pressure chamber group G2, and a fourth heating resistor 607 arranged along the Y-axis direction which is the arrangement direction of each pressure chamber 12 included in the second pressure chamber group G2, outside the liquid ejection head 510 with respect to the fourth detection resistor 407. The fourth detection resistor 407 detects the temperature of the ink in the pressure chamber 12 included in the second pressure chamber group G2, and the fourth heating resistor 607 heats the ink in the pressure chamber 12 included in the second pressure chamber group G2.

[0094] The liquid ejection head 510 includes a fifth detection resistor 408 arranged along the Y-axis direction, which is the arrangement direction of each pressure chamber 12 included in the third pressure chamber group G3, on the outer side of the liquid ejection head 510 with respect to the third pressure chamber group G3, and a fifth heating resistor 608 arranged along the Y-axis direction, which is the arrangement direction of each pressure chamber 12 included in the third pressure chamber group G3, on the outer side of the liquid ejection head 510 with respect to the fifth detection resistor 408. The fifth detection resistor 408 detects the temperature of the ink in the pressure chamber 12 included in the third pressure chamber group G3, and the fifth heating resistor 608 heats the ink in the pressure chamber 12 included in the third pressure chamber group G3.

[0095] The liquid ejection head 510 includes a sixth detection resistor 409 arranged along the Y-axis direction, which is the arrangement direction of each pressure chamber 12 included in the fourth pressure chamber group G4, on the outer side of the liquid ejection head 510 with respect to the fourth pressure chamber group G4, and a sixth heating resistor 609 arranged along the Y-axis direction, which is the arrangement direction of each pressure chamber 12 included in the fourth pressure chamber group G4, on the outer side of the liquid ejection head 510 with respect to the sixth detection resistor 409. The sixth detection resistor 409 detects the temperature of the ink in the pressure chamber 12 included in the fourth pressure chamber group G4, and the sixth heating resistor 609 heats the ink in the pressure chamber 12 included in the fourth pressure chamber group G4.

[0096] The measurement lead electrode 93 includes measurement lead electrodes 93c, 93d, 93e, 93f, 93g, and 93h in addition to the measurement lead electrodes 93a and 93b. The heating lead electrode 94 includes heating lead electrodes 94c, 94d, 94e, 94f, 94g, and 94h in addition to the heating lead electrodes 94a and 94b.

[0097] The third heating resistor 606 is continuous. One end of the third heating resistor 606 is connected to the heating lead electrode 94e, and the other end of the third heating resistor 606 is connected to the heating lead electrode 94a. The fourth heating resistor 607 is continuous. One end of the fourth heating resistor 607 is connected to the heating lead electrode 94c, and the other end of the fourth heating resistor 607 is connected to the heating lead electrode 94g. The fifth heating resistor 608 is continuous. One end of the fifth heating resistor 608 is connected to the heating lead electrode 94f, and the other end of the fifth heating resistor 608 is connected to the heating lead electrode 94b. The sixth heating resistor 609 is continuous. One end of the sixth heating resistor 609 is connected to the heating lead electrode 94d, and the other end of the sixth heating resistor 609 is connected to the heating lead electrode 94h. Thereby, the third heating resistor 606 is connected to the wiring board 120, and the control unit 580 can apply a voltage to the third heating resistor 606. The fourth heating resistor 607 is connected to the wiring board 120, and the control unit 580 can apply a voltage to the fourth heating resistor 607. The fifth heating resistor 608 is connected to the wiring board 120, and the control unit 580 can apply a voltage to the fifth heating resistor 608. The sixth heating resistor 609 is connected to the wiring board 120, and the control unit 580 can apply a voltage to the sixth heating resistor 609.

[0098] The third detection resistor 406 is continuous. One end of the third detection resistor 406 is connected to the measurement lead electrode 93e, and the other end of the third detection resistor 406 is connected to the measurement lead electrode 93a. The fourth detection resistor 407 is continuous. One end of the fourth detection resistor 407 is connected to the measurement lead electrode 93c, and the other end of the fourth detection resistor 407 is connected to the measurement lead electrode 93g. The fifth detection resistor 408 is continuous. One end of the fifth detection resistor 408 is connected to the measurement lead electrode 93f, and the other end of the fifth detection resistor 408 is connected to the measurement lead electrode 93b. The sixth detection resistor 409 is continuous. One end of the sixth detection resistor 409 is connected to the measurement lead electrode 93d, and the other end of the sixth detection resistor 409 is connected to the measurement lead electrode 93h. As a result, the third detection resistor 406 is connected to the wiring board 120, and the control unit 580 can measure the electrical resistance value of the third detection resistor 406. The fourth detection resistor 407 is connected to the wiring board 120, and the control unit 580 can measure the electrical resistance value of the fourth detection resistor 407. The fifth detection resistor 408 is connected to the wiring board 120, and the control unit 580 can measure the electrical resistance value of the fifth detection resistor 408. The sixth detection resistor 409 is connected to the wiring board 120, and the control unit 580 can measure the electrical resistance value of the sixth detection resistor 409.

[0099] According to the liquid ejection head 510 of the present embodiment, for example, the temperature of the ink in the pressure chamber 12 included in the first pressure chamber group G1, the temperature of the ink in the pressure chamber 12 included in the third pressure chamber group G3, the temperature of the ink in the pressure chamber 12 included in the second pressure chamber group G2, and the temperature of the ink in the pressure chamber 12 included in the fourth pressure chamber group G4 can be individually heated and temperature-adjusted. Even when the temperature of the ink is different for each pressure chamber group, the temperature of the ink can be individually adjusted to an appropriate temperature. The liquid ejection device 500 can more easily perform the ejection control of the liquid ejection head 510 suitable for the temperature of the ink in the pressure chamber 12.

[0100] According to the liquid ejection head 510 of the present embodiment, for example, when the temperature of the ink in the pressure chamber 12 included in the first pressure chamber group G1, the temperature of the ink in the pressure chamber 12 included in the third pressure chamber group G3, the temperature of the ink in the pressure chamber 12 included in the second pressure chamber group G2, and the temperature of the ink in the pressure chamber 12 included in the fourth pressure chamber group G4 are different, the piezoelectric element 300 corresponding to the temperature of the ink in the pressure chamber 12 included in each pressure chamber row can be driven. Further, according to this, the liquid ejection device 500 can more easily perform ejection control of the liquid ejection head 510 suitable for the temperature of the ink in the pressure chamber 12.

[0101] E. Other forms: (E1) In the first embodiment described above, the heating resistor 601 is formed of platinum (Pt), which is the same material as the first electrode 60 that is an individual electrode. On the other hand, the heating resistor 601 is not limited to the same material, and may be formed of the same material as either the common electrode or the drive wiring. The same effect can be obtained even with the liquid ejection head 510 of this form.

[0102] (E2) In the first embodiment described above, the heating resistor 601 is disposed at the same position in the stacking direction as the first electrode 60 that is an individual electrode, that is, in the same layer as the first electrode 60. On the other hand, the heating resistor 601 is not limited to the same layer as the individual electrode, and may be disposed in the same layer as either the common electrode or the drive wiring. The same effect can be obtained even with the liquid ejection head 510 of this form.

[0103] (E3) In the first embodiment described above, the material of the detection resistor 401 is platinum (Pt), and it is formed of the same material as the first electrode 60. On the other hand, the detection resistor 401 is not limited to the individual electrode, and may be formed of the same material as either the common electrode or the drive wiring. Thereby, compared with the case where the detection resistor 401 is formed separately from the common electrode or the drive wiring, the manufacturing process can be simplified and the cost can be reduced.

[0104] (E4) In the above-described second embodiment, the detection resistor 401 is formed of the same material as the first electrode 60 which is an individual electrode. In contrast, the detection resistor 401 may be formed of the same material as the second electrode 80 which is a common electrode. According to the liquid ejection head 510 of this embodiment, for example, the detection resistor 401 and the heating resistor 651 can be formed in the formation process of the second electrode 80, and the manufacturing process can be simplified and the cost can be reduced.

[0105] (E5) In the above-described second embodiment, an example in which the second electrode 80 is iridium (Ir) and the first electrode 60 is platinum (Pt) was shown. That is, in the second embodiment, the second electrode 80 which is a common electrode is formed of a material having a higher electrical resistance than the first electrode 60 which is an individual electrode, whereas the first electrode 60 is formed of a material having a larger change rate of electrical resistance with respect to temperature change than the second electrode 80 which is a common electrode, and an example in which the heating resistor 651 is formed of the same material as the second electrode 80 which is a common electrode was shown. In contrast, the first electrode 60 which is an individual electrode may be formed of a material having a higher electrical resistance than the second electrode 80 which is a common electrode, the second electrode 80 which is a common electrode may be formed of a material having a larger change rate of electrical resistance with respect to temperature change than the first electrode 60 which is an individual electrode, and the heating resistor 651 may be formed of the same material as the first electrode 60 which is an individual electrode. In this case, the detection resistor 401 may be formed of the same material as the first electrode 60 which is an individual electrode. The detection resistor 401 and the heating resistor 651 can be formed in the formation process of the first electrode 60, and the manufacturing process can be simplified and the cost can be reduced. Further, in this case, the detection resistor 401 is not limited to the same material as the first electrode 60 which is an individual electrode, and may be formed of the same material as the second electrode 80 which is a common electrode.

[0106] (E6) In the above-described first embodiment, an example is shown in which the heating resistor 601 is formed on the surface of the diaphragm 50 on the -Z direction side so as to be in the same layer as the first electrode 60 and electrically discontinuous from the first electrode 60. On the other hand, the heating resistor 601 may be formed in the same layer as the individual lead electrodes 91 and the common lead electrode 92 that function as drive wirings, and the heating lead electrodes 94a and 94b including the heating lead electrode 94, and laminated on the surface of the piezoelectric body 70 on the -Z direction side so as to be electrically continuous with the heating lead electrode 94. That is, the heating resistor 601 may be the same wiring as the heating lead electrode 94. For this reason, the heating resistor 601 is made of the same layer as the individual lead electrode 91 and the common lead electrode 92, but is formed so as to be electrically discontinuous, and the material of the heating resistor 601 is gold (Au), which is the same material as the individual lead electrode 91 and the common lead electrode 92. Thereby, compared with the case where the heating resistor 601 is formed individually from the individual lead electrode 91 and the common lead electrode 92, the manufacturing process can be simplified and the cost can be reduced.

[0107] (E7) In the above-described first embodiment, an example is shown in which the detection resistor 401 is formed on the surface of the diaphragm 50 on the -Z direction side so as to be in the same layer as the first electrode 60 and electrically discontinuous from the first electrode 60. On the other hand, the detection resistor 401 may be formed in the same layer as the individual lead electrodes 91 and the common lead electrode 92 that function as drive wirings, and the measurement lead electrodes 93a and 93b including the measurement lead electrode 93, and laminated on the surface of the piezoelectric body 70 on the -Z direction side so as to be electrically continuous with the measurement lead electrode 93. That is, the detection resistor 401 may be the same wiring as the measurement lead electrode 93. For this reason, the detection resistor 401 is made of the same layer as the individual lead electrode 91 and the common lead electrode 92, but is formed so as to be electrically discontinuous, and the material of the detection resistor 401 is gold (Au), which is the same material as the individual lead electrode 91 and the common lead electrode 92. Thereby, compared with the case where the detection resistor 401 is formed individually from the individual lead electrode 91 and the common lead electrode 92, the manufacturing process can be simplified and the cost can be reduced.

[0108] The present disclosure is not limited to the above-described embodiments, and can be implemented in various configurations without departing from the gist thereof. For example, the technical features in the embodiments corresponding to the technical features in each form described in the summary of the invention can be appropriately replaced or combined in order to solve some or all of the above-described problems, or to achieve some or all of the above-described effects. Further, if the technical feature is not described as essential in this specification, it can be appropriately deleted.

[0109] (1) According to one aspect of the present disclosure, a liquid ejection head is provided. This liquid ejection head includes a pressure chamber substrate having a plurality of pressure chambers, and a piezoelectric element laminated on the pressure chamber substrate. The piezoelectric element includes an individual electrode provided individually for each of the plurality of pressure chambers, a common electrode provided commonly for the plurality of pressure chambers, and a piezoelectric body provided between the individual electrode and the common electrode in the lamination direction of the piezoelectric element for applying pressure to the liquid in the pressure chamber. The liquid ejection head further includes a drive wiring electrically connected to the individual electrode and the common electrode for applying a voltage for driving the piezoelectric body to the piezoelectric body, and a heating resistor formed of the same material as any of the individual electrode, the common electrode, and the drive wiring for heating the liquid in the pressure chamber. According to the liquid ejection head of this aspect, a heating resistor can be provided inside the liquid ejection head. Compared with a liquid ejection head having a heater outside, the distance from the pressure chamber to the heating resistor can be shortened, and the temperature of the liquid in the pressure chamber can be controlled and adjusted well. Further, by providing a heating resistor inside the liquid ejection head, an increase in the size of the liquid ejection head can be suppressed.

[0110] (2) In the liquid ejection head of the above aspect, at least a part of the heating resistor may be disposed at the same position in the lamination direction as any of the individual electrode, the common electrode, and the drive wiring. According to the liquid ejection head of this aspect, the heating resistor can be formed in the same process as the process of forming the individual electrode.

[0111] (3) In the liquid ejection head of the above-described embodiment, the plurality of pressure chambers may be arranged along a predetermined arrangement direction in the pressure chamber substrate. At least a part of the heating resistor may be disposed outside the liquid ejection head in a crossing direction that crosses the arrangement direction with respect to the pressure chamber. According to the liquid ejection head of this embodiment, heat dissipation from the pressure chamber to the outside of the liquid ejection head can be reduced, and the temperature of the liquid in the pressure chamber can be efficiently adjusted.

[0112] (4) In the liquid ejection head of the above-described embodiment, the plurality of pressure chambers may include a first pressure chamber row and a second pressure chamber row adjacent to the first pressure chamber row in the crossing direction. The heating resistor may include a first heating resistor for heating the pressure chambers included in the first pressure chamber row and a second heating resistor for heating the pressure chambers included in the second pressure chamber row. According to the liquid ejection head of this embodiment, the temperature of the liquid in the pressure chambers included in the first pressure chamber row and the temperature of the liquid in the pressure chambers included in the second pressure chamber row can be individually heated and temperature-adjusted.

[0113] (5) In the liquid ejection head of the above-described embodiment, the plurality of pressure chambers may include a first pressure chamber row and a second pressure chamber row adjacent to the first pressure chamber row in the crossing direction. The first pressure chamber row may include a first pressure chamber group including a plurality of pressure chambers located on one side in the arrangement direction among the plurality of pressure chambers and a second pressure chamber group including a plurality of pressure chambers located on the other side in the arrangement direction among the plurality of pressure chambers. The heating resistor may include a third heating resistor for heating the plurality of pressure chambers included in the first pressure chamber group and a fourth heating resistor for heating the plurality of pressure chambers included in the second pressure chamber group. According to the liquid ejection head of this embodiment, the temperature of the liquid in the pressure chambers included in the first pressure chamber group and the temperature of the liquid in the pressure chambers included in the second pressure chamber group can be individually heated and temperature-adjusted.

[0114] (6) In the liquid ejection head of the above-described embodiment, further, a detection resistor for detecting the temperature in the pressure chamber, the detection resistor may be formed of the same material as any one of the individual electrodes, the common electrode, and the drive wiring. According to the liquid ejection head of this embodiment, since the detection resistor is provided in the liquid ejection head, the difference between the temperature detected by the detection resistor and the temperature in the pressure chamber can be made smaller as compared with the case of measuring the temperature outside the liquid ejection head.

[0115] (7) In the liquid ejection head of the above-described embodiment, the common electrode may be formed of a material having a higher electrical resistance than the individual electrodes, the individual electrodes may be formed of a material having a larger change rate of electrical resistance with respect to temperature change than the common electrode, and the heating resistor may be formed of the same material as the common electrode. According to the liquid ejection head of this embodiment, suitable materials can be applied to each of the heating resistor and the detection resistor.

[0116] (8) In the liquid ejection head of the above-described embodiment, the detection resistor may be formed of the same material as the individual electrodes. According to the liquid ejection head of this embodiment, it is easy to form the detection resistor in the same process as the individual electrodes when forming the detection resistor.

[0117] (9) In the liquid ejection head of the above-described embodiment, the detection resistor may be formed of the same material as the common electrode. According to the liquid ejection head of this embodiment, it is easy to form the detection resistor in the same process as the common electrode when forming the detection resistor.

[0118] (10) In the liquid ejection head of the above-described embodiment, the individual electrodes may be formed of a material having a higher electrical resistance than the common electrode, the common electrode may be formed of a material having a larger change rate of electrical resistance with respect to temperature change than the individual electrodes, and the heating resistor may be formed of the same material as the individual electrodes.

[0119] (11) In the liquid ejection head of the above-described aspect, the detection resistor may be formed of the same material as the common electrode. According to the liquid ejection head of this aspect, when forming the detection resistor, it is easy to form in the same process as the common electrode.

[0120] (12) In the liquid ejection head of the above-described aspect, the detection resistor may be formed of the same material as the individual electrode. According to the liquid ejection head of this aspect, when forming the detection resistor, it is easy to form in the same process as the individual electrode.

[0121] (13) In the liquid ejection head of the above-described aspect, the common electrode may contain iridium, and the individual electrode may contain platinum.

[0122] (14) In the liquid ejection head of the above-described aspect, the heating resistor may be disposed outside the liquid ejection head rather than the detection resistor. According to the liquid ejection head of this aspect, by disposing the detection resistor at a position closer to the pressure chamber, the detection of the temperature of the pressure chamber by the detection resistor is prioritized over the temperature adjustment of the pressure chamber by the heating resistor, and the detection accuracy of the temperature of the pressure chamber can be increased.

[0123] (15) In the liquid ejection head of the above-described aspect, the cross-sectional area of the heating resistor may be smaller than the cross-sectional area of the detection resistor. According to the liquid ejection head of this aspect, the electrical resistance of the heating resistor becomes larger than the electrical resistance of the detection resistor, and heating can be performed more efficiently using the resistive heating of the heating resistor.

[0124] (16) In the liquid ejection head of the above-described aspect, the length of the heating resistor may be longer than the length of the detection resistor. According to the liquid ejection head of this aspect, the electrical resistance of the heating resistor becomes larger than the electrical resistance of the detection resistor, and heating can be performed more efficiently using the resistive heating of the heating resistor.

[0125] (17) In the liquid ejection head of the above-described form, the power supply circuit for supplying power to the piezoelectric body and the power supply circuit for supplying power to the heating resistor and the detection resistor may be different circuits from each other. According to the liquid ejection head of this form, the drive control of the piezoelectric element, the heating of the liquid in the pressure chamber by the heating resistor, and the temperature detection of the pressure chamber by the detection resistor can be executed individually.

[0126] (18) According to another form of the present disclosure, a liquid ejection device is provided. This liquid ejection device includes the liquid ejection head in the above-described first form and a control unit that controls the ejection operation of the liquid from the liquid ejection head. According to the liquid ejection device of this form, a configuration capable of controlling the ejection operation of the liquid ejection head can be easily realized.

[0127] The present disclosure can also be realized in various forms other than the liquid ejection device. For example, it can be realized in the form of a manufacturing method of a liquid ejection device, a control method of a liquid ejection device, a computer program that realizes the control method, a non-transitory recording medium on which the computer program is recorded, and the like.

[0128] The present disclosure is not limited to the inkjet method and can also be applied to any liquid ejection device that ejects liquids other than ink and the liquid ejection heads used in those liquid ejection devices. For example, it is applicable to the following various liquid ejection devices and their liquid ejection heads. (1) An image recording device such as a facsimile machine. (2) A colorant ejection device used for manufacturing a color filter for an image display device such as a liquid crystal display. (3) An electrode material ejection device used for forming electrodes of an organic EL (Electro Luminescence) display, a field emission display (FED), or the like. (4) A liquid ejection device that ejects a liquid containing a biological organic substance used for manufacturing a biochip. (5) A sample ejection device as a precision pipette. (6) A lubricating oil ejection device. (7) Resin liquid ejection device. (8) Liquid ejection device for pinpoint ejection of lubricating oil onto precision machinery such as watches and cameras. (9) Liquid ejection device for ejecting a transparent resin liquid such as an ultraviolet curable resin liquid onto a substrate to form a micro hemispherical lens (optical lens) used for an optical communication element or the like. (10) Liquid ejection device for ejecting an acidic or alkaline etching liquid for etching a substrate or the like. (11) Liquid ejection device including a liquid consumption head for ejecting any other arbitrary minute droplets.

[0129] "Droplet" refers to the state of the liquid ejected from the liquid ejection device, and includes granular, teardrop-shaped, and those trailing in a thread-like shape. Further, the "liquid" here may be any material that can be consumed by the liquid ejection device. For example, the "liquid" may be a material in a state when the substance is in a liquid phase, and includes highly viscous or low viscous liquid state materials, and liquid state materials such as sol, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, and liquid metals (molten metals). Further, not only liquids as a state of matter, but also those in which particles of functional materials composed of solids such as pigments and metal particles are dissolved, dispersed, or mixed in a solvent are also included in the "liquid". Further, typical examples of the combination of the first liquid and the second liquid include, in addition to the combination of ink and reaction liquid as described in the above embodiment, the following. (1) Main agent and curing agent of adhesive (2) Base paint and thinner of paint, and clear paint and thinner (3) Main solvent containing cells and diluting solvent of ink for cells (4) Metallic leaf pigment dispersion liquid and diluting solvent of ink (metallic ink) expressing metallic luster (5) Gasoline, light oil, and biofuel of vehicle fuel (6) Main drug component and protective component of drug (7) Phosphor and encapsulant of light emitting diode (LED)

Explanation of reference numerals

[0130] 10…Pressure chamber substrate, 11…Partition wall, 12…Pressure chamber, 12a, 12b…Ends, 15…Communication plate, 16…Nozzle communication path, 17…First manifold section, 18…Second manifold section, 19…Supply communication path, 20…Nozzle plate, 21…Nozzle, 30…Protection substrate, 31…Holding section, 32…Through hole, 40…Case member, 41…Accommodation section, 42…Third manifold section, 43…Connection port, 44…Supply port, 45…Compliance substrate, 46…Sealing film, 47…Fixed substrate, 48…Opening, 49…Compliance section, 50…Diaphragm, 51…Elastic film, 52…Insulator film, 60…First electrode, 60a, 60b…Ends, 70…Piezoelectric body, 70a, 70b…Ends, 71…Groove section, 80…Second electrode, 80a, 80b…Ends, 85…Wiring section, 91…Individual lead electrode, 92…Common lead electrode, 92a, 92b…Extended sections, 93, 93a~93h…Measurement lead electrodes, 94, 94a~94h…Heating lead electrodes, 100…Manifold, 120…Wiring substrate, 121…Head circuit, 300…Piezoelectric element, 310…Active section, 320…Inactive section, 401…Detection resistor, 402…First detection resistor, 403…Second detection resistor, 406…Third detection resistor, 407…Fourth detection resistor, 408…Fifth detection resistor, 409…Sixth detection resistor, 500…Liquid ejection device, 510…Liquid ejection head, 550…Ink tank, 552…Tube, 560…Conveying mechanism, 562…Conveying roller, 564…Conveying rod, 566…Conveying motor, 570…Moving mechanism, 572…Carriage, 574…Conveying belt, 576…Moving motor, 577…Pulley, 580…Control unit, 601, 651…Heating resistor, 602…First heating resistor, 603…Second heating resistor, 606…Third heating resistor, 607…Fourth heating resistor, 608…Fifth heating resistor, 609…Sixth heating resistor, G1…First pressure chamber group, G2…Second pressure chamber group, G3…Third pressure chamber group, G4…Fourth pressure chamber group, L1…First pressure chamber row, L2…Second pressure chamber row, P…Printing paper

Claims

1. A liquid ejection head comprising: a pressure chamber substrate having a plurality of pressure chambers; a piezoelectric element laminated on the pressure chamber substrate, the piezoelectric element including individual electrodes provided individually for each of the plurality of pressure chambers, a common electrode provided commonly for the plurality of pressure chambers, and a piezoelectric body provided between the individual electrode and the common electrode in the lamination direction of the piezoelectric element for applying pressure to the liquid in the pressure chamber; a drive wiring electrically connected to the individual electrode and the common electrode for applying a voltage for driving the piezoelectric body to the piezoelectric body; a heating resistor formed of the same material as any one of the individual electrode, the common electrode, and the drive wiring for heating the liquid in the pressure chamber; a detection resistor formed of the same material as any one of the individual electrode, the common electrode, and the drive wiring for detecting the temperature in the pressure chamber, the detection resistor being different from the heating resistor; A liquid ejection head.

2. The liquid ejection head according to claim 1, wherein at least a part of the heating resistor is disposed at the same position as any one of the individual electrode, the common electrode, and the drive wiring in the lamination direction. A liquid ejection head.

3. The liquid ejection head according to claim 1 or 2, wherein the plurality of pressure chambers are arranged along a predetermined arrangement direction in the pressure chamber substrate, and at least a part of the heating resistor is disposed outside the liquid ejection head in a direction intersecting the arrangement direction, outside the pressure chamber. A liquid ejection head.

4. The liquid ejection head according to claim 3, wherein the plurality of pressure chambers include a first pressure chamber row and a second pressure chamber row adjacent to the first pressure chamber row in the intersecting direction, and the heating resistor includes a first heating resistor for heating the pressure chambers included in the first pressure chamber row and a second heating resistor for heating the pressure chambers included in the second pressure chamber row. A liquid ejection head.

5. The liquid ejection head according to claim 3, wherein the plurality of pressure chambers include a first pressure chamber row and a second pressure chamber row adjacent to the first pressure chamber row in the intersecting direction, and the first pressure chamber row includes a first pressure chamber group including a plurality of pressure chambers located on one side in the arrangement direction among the plurality of pressure chambers and a second pressure chamber group including a plurality of pressure chambers located on the other side in the arrangement direction among the plurality of pressure chambers. The heating resistor includes a third heating resistor for heating the plurality of pressure chambers included in the first pressure chamber group, and a fourth heating resistor for heating the plurality of pressure chambers included in the second pressure chamber group. Liquid ejection head.

6. A liquid ejection head according to any one of claims 1 to 5, wherein the heating resistor is made of a material having a larger electrical resistance than the detection resistor and a smaller change rate of electrical resistance with respect to temperature change than the detection resistor. Liquid ejection head.

7. A liquid ejection head according to claim 6, wherein the heating resistor is formed of the same material as the common electrode, and the detection resistor is formed of the same material as the individual electrode. Liquid ejection head.

8. A liquid ejection head according to claim 6 or claim 7, wherein the heating resistor contains iridium, and the detection resistor contains platinum. Liquid ejection head.

9. A liquid ejection head according to any one of claims 1 to 8, wherein the heating resistor is disposed outside the liquid ejection head more than the detection resistor. Liquid ejection head.

10. A liquid ejection head according to any one of claims 1 to 9, wherein a cross-sectional area of the heating resistor is smaller than a cross-sectional area of the detection resistor. Liquid ejection head.

11. A liquid ejection head according to any one of claims 1 to 10, wherein a length of the heating resistor is longer than a length of the detection resistor. Liquid ejection head.

12. A liquid ejection head according to any one of claims 1 to 11, wherein a power supply circuit for supplying power to the piezoelectric body and a power supply circuit for supplying power to the heating resistor and the detection resistor are different circuits from each other. Liquid ejection head.

13. A liquid ejection head according to any one of claims 1 to 12, and a control unit for controlling a liquid ejection operation from the liquid ejection head. Liquid ejection device.

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