Patent Description:
The present disclosure relates to a liquid ejecting head and a liquid ejecting apparatus.

There is known a liquid ejecting head including a pressure chamber plate provided with pressure chambers, a vibration plate for generating a pressure in the pressure chamber, and a piezoelectric actuator including a piezoelectric element provided on the vibration plate. For example, <CIT> discloses that a piezoelectric actuator is covered with a case portion and a humidity sensor is provided in a space inside the case portion. <CIT> is an example of the related art.

Performance of the piezoelectric actuator or a member in the vicinity of the piezoelectric actuator may be deteriorated because of an influence of humidity. The technique in the related art does not propose, for example, a specific structure for adopting a humidity sensor, such as a structure of the humidity sensor itself, a disposition position of the humidity sensor with respect to the piezoelectric actuator and the member in the vicinity of the piezoelectric actuator, and the like. As a result, in the technique in the related art, there is a possibility that information on humidity in the piezoelectric actuator or the member in the vicinity of the piezoelectric actuator cannot be appropriately acquired.

<CIT> discloses a liquid jet head in which a detection circuit includes, on a head substrate a set of detection wiring formed along an array of piezoelectric elements; and plural resistors located at a position previously set on the head substrate and serially connected by the detection wiring. The detection circuit includes, on the head substrate, detection wiring that is divided into plural zones by the plural resistors, detects a resistance value of the detection wiring, where the resistance value differs depending on a zone that is attached with moisture, thus determining a zone attached with moisture from the moisture attached zone.

<CIT> discloses an ink jet recording head in which a substrate <NUM> comprises a piezoelectric vibrator consisting of a vibration plate that forms a part of a pressurizing chamber with a nozzle, which can be capped. An environment detecting means is provided for detecting the change in environment of the space in a cap member <NUM>.

<CIT> discloses an ink-jet recording head in which rigidity of a compartment wall is improved and pressure generating chambers are arranged in a high density. Pressure generating chambers communicate with a nozzle orifice. A piezoelectric element generates a pressure change in the pressure generating chamber, the piezoelectric element being provided in a region opposite the pressure generating chamber via a vibration plate, which constitutes a portion of the pressure generating chamber.

According to an aspect of the present disclosure, a liquid ejecting head is provided. A liquid ejecting head includes: a piezoelectric element that includes a first drive electrode, a second drive electrode, and a piezoelectric body, the piezoelectric body being provided between the first drive electrode and the second drive electrode in a lamination direction in which the first drive electrode, the second drive electrode, and the piezoelectric body are laminated; a vibration plate that is provided on one side of the lamination direction with respect to the piezoelectric element and is deformed by driving of the piezoelectric element; a pressure chamber substrate that is provided on the one side of the lamination direction with respect to the vibration plate and is provided with a plurality of pressure chambers; an interlayer that is laminated on at least one of the piezoelectric body, the vibration plate, or the pressure chamber substrate and of which resistance changes according to humidity; a first detection electrode that is in contact with the interlayer; and a second detection electrode that is in contact with the interlayer and faces the first detection electrode.

<FIG> is an explanatory diagram illustrating a schematic configuration of a liquid ejecting apparatus <NUM> as a first embodiment of the present disclosure. In the present embodiment, the liquid ejecting apparatus <NUM> is an ink jet printer that forms an image by ejecting ink as an example of a liquid onto printing paper P. The liquid ejecting apparatus <NUM> may use any kind of medium, such as a resin film or a cloth, as a target on which ink is to be ejected, instead of the printing paper P. X, Y, and Z illustrated in <FIG> and each of the drawings subsequent to <FIG> represent three spatial axes orthogonal to each other. In the present specification, directions along the axes are also referred to as an X-axis direction, a Y-axis direction, and a Z-axis direction. When specifying the direction, a positive direction is "+" and a negative direction is "-" so that positive and negative signs are used together in the direction notation, and description will be given when a direction to which an arrow faces in each of the drawings is the + direction and an opposite direction thereof is the - direction. In the present embodiment, the Z-axis direction coincides with a vertical direction, the +Z direction indicates vertically downward, and the -Z direction indicates vertically upward. Further, when the positive direction and the negative direction are not limited, the three X, Y, and Z will be described as the X-axis, the Y-axis, and the Z-axis.

The liquid ejecting apparatus <NUM> includes a liquid ejecting head <NUM>, an ink tank <NUM>, a transport mechanism <NUM>, a moving mechanism <NUM>, and a control device <NUM>. The liquid ejecting head <NUM> is configured with a plurality of nozzles, ejects inks of a total of four colors, for example, black, cyan, magenta, and yellow in the +Z direction to form an image on a printing paper P. The liquid ejecting head <NUM> is mounted on a carriage <NUM> and reciprocates in main scanning directions with the movement of the carriage <NUM>. In the present embodiment, the main scanning directions are the +X direction and the -X direction. The liquid ejecting head <NUM> may further eject ink of a random color such as light cyan, light magenta, or white, and transparent ink in addition to the four colors.

The ink tank <NUM> accommodates the ink to be ejected to the liquid ejecting head <NUM>. The ink tank <NUM> is coupled to the liquid ejecting head <NUM> by a resin tube <NUM>. The ink in the ink tank <NUM> is supplied to the liquid ejecting head <NUM> via the tube <NUM>. Instead of the ink tank <NUM>, a bag-shaped liquid pack formed of a flexible film may be provided.

The transport mechanism <NUM> transports the printing paper P in a sub-scanning direction. The sub-scanning direction is a direction that intersects with the X-axis direction, which is a main scanning direction, and is the +Y direction and the -Y direction in the present embodiment. The transport mechanism <NUM> includes a transport rod <NUM>, on which three transport rollers <NUM> are mounted, and a transport motor <NUM> for rotatably driving the transport rod <NUM>. When the transport motor <NUM> rotatably drives the transport rod <NUM>, the printing paper P is transported in the +Y direction, which is the sub-scanning direction. The number of the transport rollers <NUM> is not limited to three and may be a random number. Further, a configuration in which a plurality of transport mechanisms <NUM> are provided may be provided.

The moving mechanism <NUM> includes a carriage <NUM>, a transport belt <NUM>, a moving motor <NUM>, and a pulley <NUM>. The carriage <NUM> mounts the liquid ejecting head <NUM> in a state where the ink can be ejected. The carriage <NUM> is fixed to the transport belt <NUM>. The transport belt <NUM> is bridged between the moving motor <NUM> and the pulley <NUM>. When the moving motor <NUM> is rotatably driven, the transport belt <NUM> reciprocates in the main scanning direction. Thereby, the carriage <NUM> fixed to the transport belt <NUM> also reciprocates in the main scanning direction.

<FIG> is a block diagram illustrating a functional configuration of the liquid ejecting apparatus <NUM>. In <FIG>, a partial configuration of the liquid ejecting apparatus <NUM> such as the ink tank <NUM>, the transport mechanism <NUM>, and the moving mechanism <NUM> is omitted. As illustrated in <FIG>, the liquid ejecting head <NUM> includes a piezoelectric element <NUM>, a humidity detection mechanism <NUM>, and a temperature detection mechanism <NUM>.

The piezoelectric element <NUM> causes a pressure change in the ink in the pressure chamber of the liquid ejecting head <NUM>. The humidity detection mechanism <NUM> functions as a so-called electric humidity sensor, and acquires information on humidity in a member included in the liquid ejecting head <NUM>, such as the piezoelectric element <NUM>, or a member on the periphery of the humidity detection mechanism <NUM>. "Information on humidity" includes, for example, an amount of moisture absorbed or dehumidified from a member, an amount of moisture contained in the air, a degree of an influence on performance of a member because of moisture absorption or dehumidification, and information used to obtain such information, such as a resistance value or a capacitance value. The "degree of an influence on performance of a member" may include the presence or absence of a failure of the member, a temporal change in the performance of the member, and the like.

As illustrated in <FIG>, the humidity detection mechanism <NUM> includes a humidity detection section <NUM>, a humidity-detection power supply section <NUM>, and a humidity-detection resistance measurement section <NUM>. In the present embodiment, the humidity detection section <NUM> is configured with a resistance-detection-type humidity sensor, and uses a property that conductivity of a measurement target changes with moisture absorption. The humidity-detection power supply section <NUM> is, for example, a constant current circuit, and causes a predetermined current to flow through the humidity detection section <NUM> under a control of a humidity management section <NUM>. The humidity-detection resistance measurement section <NUM> detects a resistance value of the humidity detection section <NUM> based on a current value of a current flowing through the humidity detection section <NUM> by the humidity-detection power supply section <NUM> and a voltage value of a voltage generated in the humidity detection section <NUM>. A detection result by the humidity-detection resistance measurement section <NUM> is output to the humidity management section <NUM>. The humidity-detection power supply section <NUM> may be a circuit that applies a predetermined voltage to the humidity detection section <NUM>. The humidity-detection power supply section <NUM> and the humidity-detection resistance measurement section <NUM> may be provided in the control device <NUM>.

The temperature detection mechanism <NUM> functions as a temperature sensor that detects a temperature of the ink in a pressure chamber to be described later. Specifically, the temperature detection mechanism <NUM> detects a temperature of a resistance wiring by using a characteristic that a resistance value of a resistance wiring of a metal, a semiconductor, or the like changes depending on a temperature, and estimates the detected temperature of the resistance wiring as a temperature of the ink in the pressure chamber.

The temperature detection mechanism <NUM> includes a temperature detection section <NUM>, a temperature-detection power supply section <NUM>, and a temperature-detection resistance measurement section <NUM>. The temperature detection section <NUM> is configured with a conductor wiring including a resistor for temperature detection. The temperature-detection power supply section <NUM> is, for example, a constant current circuit, and causes a predetermined current to flow through the temperature detection section <NUM> under a control of a temperature management section <NUM>. The temperature-detection resistance measurement section <NUM> acquires a resistance value of a temperature detection resistor of the temperature detection section <NUM> based on a current value of a current flowing through the temperature detection section <NUM> by the temperature-detection power supply section <NUM> and a voltage value of a voltage generated in the temperature detection section <NUM>. A detection result by the temperature-detection resistance measurement section <NUM> is output to the temperature management section <NUM>.

As illustrated in <FIG>, the control device <NUM> is configured as a microcomputer including a CPU <NUM> and a storage section <NUM>. The control device <NUM> is mounted on, for example, a wiring substrate <NUM> or a circuit substrate directly or indirectly coupled to the wiring substrate <NUM>. As the storage section <NUM>, for example, a non-volatile memory such as EEPROM in which data can be erased by an electrical signal, a non-volatile memory such as One-Time-PROM or EPROM in which data can be erased by ultraviolet rays, a non-volatile memory such as PROM in which data cannot be erased, and the like can be used. The storage section <NUM> stores various programs for realizing functions provided in the present embodiment. The CPU <NUM> functions as a head control section <NUM>, a humidity management section <NUM>, and a temperature management section <NUM> by developing and executing a program stored in the storage section <NUM>. The control device <NUM> may further include a communication section for transmitting and receiving a humidity detection result or a temperature detection result to and from a predetermined server.

The head control section <NUM> collectively performs a control of each section of the liquid ejecting head <NUM>, such as an ejecting operation. The head control section <NUM> may control, for example, a reciprocating operation of the carriage <NUM> along the main scanning direction, and a transport operation of the printing paper P along the sub-scanning direction, in addition to the control of the liquid ejecting head <NUM>. As an ejecting operation of the liquid ejecting head <NUM>, the head control section <NUM> can control ejection of the ink onto the printing paper P by, for example, outputting a drive signal to the liquid ejecting head <NUM> to drive the piezoelectric element <NUM>, the drive signal being a signal based on the temperature of the ink in the pressure chamber that is acquired from the temperature management section <NUM>.

The humidity management section <NUM> derives information on humidity as a detection target by using the resistance value of the humidity detection section <NUM> that is acquired from the humidity-detection resistance measurement section <NUM> and a humidity calculation equation stored in the storage section <NUM> in advance. The humidity calculation equation indicates a correspondence relationship between the resistance value of the detection target and the humidity. Instead of the humidity calculation equation, a conversion table indicating a correspondence relationship between the resistance value of the detection target and the humidity may be used. Further, the storage section <NUM> may store a correspondence relationship between the resistance value of the detection target and the temporal change in the performance of the detection target.

The temperature management section <NUM> derives the temperature of the ink in the pressure chamber <NUM> by using the resistance value of the temperature detection resistor of the temperature detection section <NUM> that is acquired from the temperature-detection resistance measurement section <NUM> and a temperature calculation equation stored in the storage section <NUM> in advance. The temperature calculation equation indicates a correspondence relationship between the resistance value of the temperature detection resistor and the temperature. Instead of the temperature calculation equation, a conversion table indicating a correspondence relationship between the resistance value of the temperature detection resistor and the temperature may be used. The temperature management section <NUM> outputs the derived temperature of the ink in the pressure chamber <NUM> to the head control section <NUM>.

A detailed configuration of the liquid ejecting head <NUM> will be described with reference to <FIG>. <FIG> is an exploded perspective view illustrating the configuration of the liquid ejecting head <NUM>. <FIG> is an explanatory diagram illustrating the configuration of the liquid ejecting head <NUM> in plan view. In the present disclosure, the "plan view" means a state in which an object is viewed along a lamination direction to be described later. <FIG> illustrates the configuration around a pressure chamber substrate <NUM> and a vibration plate <NUM> in the liquid ejecting head <NUM>. In order to facilitate understanding of the technique, a protective film <NUM>, a sealing substrate <NUM>, a case member <NUM>, and the like are not illustrated. <FIG> is a cross-sectional view illustrating a V-V position of <FIG>.

The liquid ejecting head <NUM> includes a pressure chamber substrate <NUM>, a communication plate <NUM>, a nozzle plate <NUM>, a compliance substrate <NUM>, a vibration plate <NUM>, a sealing substrate <NUM>, a case member <NUM>, a wiring substrate <NUM>, which are illustrated in <FIG>, and a piezoelectric element <NUM> illustrated in <FIG>. The liquid ejecting head <NUM> is configured by laminating these laminated members. In the present disclosure, a direction in which the laminated members of the liquid ejecting head <NUM> are laminated is also referred to as a "lamination direction". In the present embodiment, the lamination direction coincides with the Z-axis direction. In the present disclosure, the +Z direction side with respect to a predetermined reference position is also referred to as "one side of the lamination direction" or "lower side", and the -Z direction side with respect to a predetermined reference position is also referred to as "the other side of the lamination direction" or "upper side".

The pressure chamber substrate <NUM> is configured by using, for example, a silicon substrate, a glass substrate, an SOI substrate, various ceramic substrates, and the like. As illustrated in <FIG>, a plurality of pressure chambers <NUM> are provided on the pressure chamber substrate <NUM>. An ink flow path provided on the pressure chamber substrate <NUM>, such as the pressure chamber <NUM>, is formed by anisotropically etching the pressure chamber substrate <NUM> from the surface on the +Z direction side. The pressure chamber <NUM> is formed in a substantially rectangular shape in which a length in the X-axis direction is longer than a length in the Y-axis direction in plan view. On the other hand, the shape of the pressure chamber <NUM> is not limited to the rectangular shape, and may be a parallelogram shape, a polygonal shape, a circular shape, an oval shape, or the like. The oval shape means a shape in which both end portions in a longitudinal direction are semicircular based on a rectangular shape, and includes a rounded rectangular shape, an elliptical shape, an egg shape, and the like.

As illustrated in <FIG>, a plurality of pressure chambers <NUM> are arranged along a predetermined direction in the pressure chamber substrate <NUM>. In plan view of the liquid ejecting head <NUM> along the lamination direction, a direction in which the plurality of pressure chambers <NUM> are arranged is also referred to as an "arrangement direction". In the present embodiment, the plurality of pressure chambers <NUM> are arranged in two rows parallel to each other with the Y-axis direction as the arrangement direction. In the example of <FIG>, the pressure chamber substrate <NUM> is provided with two pressure chamber rows, that is, a first pressure chamber row L1 having a first arrangement direction parallel to the Y-axis direction and a second pressure chamber row L2 having a second arrangement direction parallel to the Y-axis direction. The first pressure chamber row L1 and the second pressure chamber row L2 are disposed on both sides with the wiring substrate <NUM> interposed therebetween. Specifically, the second pressure chamber row L2 is disposed on the opposite side of the first pressure chamber row L1 with the wiring substrate <NUM> interposed therebetween in the direction that intersects with the arrangement direction of the first pressure chamber row L1. The direction orthogonal to both the arrangement direction and the lamination direction is also referred to as an "intersection direction". In the example of <FIG>, the intersection direction is the X-axis direction, and the second pressure chamber row L2 is disposed in the -X direction with respect to the first pressure chamber row L1 with the wiring substrate <NUM> interposed between the first pressure chamber row L1 and the second pressure chamber row L2. The plurality of pressure chambers <NUM> do not necessarily have to be arranged in a straight line, and, for example, the plurality of pressure chambers <NUM> may be arranged along the Y-axis direction according to so-called staggered arrangement to be alternately disposed in the intersection direction.

As illustrated in <FIG>, the communication plate <NUM>, the nozzle plate <NUM>, and the compliance substrate <NUM> are laminated on the +Z direction side of the pressure chamber substrate <NUM>. The communication plate <NUM> is, for example, a flat plate member using 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 or the like. The communication plate <NUM> is provided with a nozzle communication path <NUM>, a first manifold portion <NUM>, a second manifold portion <NUM> illustrated in <FIG>, and a supply communication path <NUM>. Preferably, the communication plate <NUM> is formed by using a material having a thermal expansion coefficient substantially the same as a thermal expansion coefficient of the pressure chamber substrate <NUM>. Thereby, when the temperatures of the pressure chamber substrate <NUM> and the communication plate <NUM> change, warpage of the pressure chamber substrate <NUM> and the communication plate <NUM> because of a difference in the thermal expansion coefficient can be suppressed.

As illustrated in <FIG>, the nozzle communication path <NUM> is a flow path that communicates the pressure chamber <NUM> and a nozzle <NUM>. The first manifold portion <NUM> and the second manifold portion <NUM> function as a part of a manifold <NUM> which is a common liquid chamber in which a plurality of pressure chambers <NUM> communicate with each other. The first manifold portion <NUM> is provided to penetrate the communication plate <NUM> in the Z-axis direction. Further, as illustrated in <FIG>, the second manifold portion <NUM> is provided on a surface of the communication plate <NUM> on the +Z direction side without penetrating the communication plate <NUM> in the Z-axis direction.

As illustrated in <FIG>, the supply communication path <NUM> is a flow path coupled to a pressure chamber supply path <NUM> provided on the pressure chamber substrate <NUM>. The pressure chamber supply path <NUM> is a flow path coupled to one end portion of the pressure chamber <NUM> in the X-axis direction via a throttle portion <NUM>. The throttle portion <NUM> is a flow path provided between the pressure chamber <NUM> and the pressure chamber supply path <NUM>. The throttle portion <NUM> is a flow path in which an inner wall protrudes from the pressure chamber <NUM> and the pressure chamber supply path <NUM> and which is formed narrower than the pressure chamber <NUM> and the pressure chamber supply path <NUM>. Thereby, the throttle portion <NUM> is set such that the flow path resistance is higher than those of the pressure chamber <NUM> and the pressure chamber supply path <NUM>. With the configuration, even when pressure is applied to the pressure chamber <NUM> by the piezoelectric element <NUM> when the ink is ejected, the ink in the pressure chamber <NUM> can be suppressed or prevented from flowing back to the pressure chamber supply path <NUM>. A plurality of supply communication paths <NUM> are arranged along the Y-axis direction, that is, the arrangement direction, and are individually provided for each of the pressure chambers <NUM>. The supply communication path <NUM> and the pressure chamber supply path <NUM> communicate the second manifold portion <NUM> with each pressure chamber <NUM>, and supply the ink in the manifold <NUM> to each pressure chamber <NUM>.

The nozzle plate <NUM> is provided on a side opposite to the pressure chamber substrate <NUM>, that is, on a surface of the communication plate <NUM> on the +Z direction side with the communication plate <NUM> interposed between the nozzle plate <NUM> and the pressure chamber substrate <NUM>. A material of the nozzle plate <NUM> is not particularly limited, and for example, a silicon substrate, a glass substrate, an SOI substrate, various ceramic substrates, and a metal substrate can be used. Examples of the metal substrate include a stainless steel substrate or the like. As the material of the nozzle plate <NUM>, an organic substance, such as a polyimide resin, can also be used. On the other hand, it is preferable to use a material for the nozzle plate <NUM> that has substantially the same thermal expansion coefficient as the thermal expansion coefficient of the communication plate <NUM>. Thereby, when the temperatures of the nozzle plate <NUM> and the communication plate <NUM> change, warpage of the nozzle plate <NUM> and the communication plate <NUM> because of the difference in the thermal expansion coefficient can be suppressed.

A plurality of nozzles <NUM> are provided on the nozzle plate <NUM>. Each nozzle <NUM> communicates with each pressure chamber <NUM> via the nozzle communication path <NUM>. As illustrated in <FIG>, the plurality of nozzles <NUM> are arranged along the arrangement direction of the pressure chambers <NUM>, that is, the Y-axis direction. The nozzle plate <NUM> is provided with two nozzle rows in which the plurality of nozzles <NUM> are arranged in a row. The two nozzle rows respectively correspond to the first pressure chamber row L1 and the second pressure chamber row L2.

As illustrated in <FIG>, the compliance substrate <NUM> is provided together with the nozzle plate <NUM> on the side opposite to the pressure chamber substrate <NUM> with the communication plate <NUM> interposed therebetween, that is, on a surface of the communication plate <NUM> on the +Z direction side. The compliance substrate <NUM> is provided on the periphery of the nozzle plate <NUM>, and covers openings of the first manifold portion <NUM> and the second manifold portion <NUM> provided in the communication plate <NUM>. The compliance substrate <NUM> includes, for example, a sealing film <NUM> made of a flexible thin film and a fixed substrate <NUM> made of a hard material such as a metal. As illustrated in <FIG>, a region of the fixed substrate <NUM> facing the manifold <NUM> is completely removed in a thickness direction, and thus an opening portion <NUM> is defined. Therefore, one surface of the manifold <NUM> is a compliance portion <NUM> sealed only by the sealing film <NUM>.

As illustrated in <FIG>, the vibration plate <NUM> and the piezoelectric element <NUM> are laminated on a side opposite to the communication plate <NUM> or the like, that is, on a surface of the pressure chamber substrate <NUM> on the -Z direction side with the pressure chamber substrate <NUM> interposed therebetween. The piezoelectric element <NUM> bends and deforms the vibration plate <NUM> to cause a pressure change in the ink in the pressure chamber <NUM>. In <FIG>, illustration of the piezoelectric element <NUM> is simplified.

The vibration plate <NUM> is provided between the piezoelectric element <NUM> and the pressure chamber substrate <NUM>. The vibration plate <NUM> is provided on the pressure chamber substrate <NUM> side, and includes an elastic film <NUM> containing silicon oxide (SiO<NUM>) and an insulator film <NUM> that is provided on the elastic film <NUM> and contains a zirconium oxide film (ZrO<NUM>). The elastic film <NUM> constitutes a surface of the flow path, such as the pressure chamber <NUM>, on the -Z direction side. The vibration plate <NUM> may be configured with, for example, either the elastic film <NUM> or the insulator film <NUM>, and may further include another film other than the elastic film <NUM> and the insulator film <NUM>. Examples of the material of the other film include silicon, silicon nitride, and the like.

As illustrated in <FIG>, the sealing substrate <NUM> having substantially the same size as the pressure chamber substrate <NUM> in plan view is further bonded to the surface of the pressure chamber substrate <NUM> on the -Z direction side by an adhesive or the like. As illustrated in <FIG>, the sealing substrate <NUM> includes a ceiling portion 30T, a wall portion 30W, a holding portion <NUM>, and a through hole <NUM>. The holding portion <NUM> is a space defined by the ceiling portion 30T and the wall portion 30W, and protects an active portion of the piezoelectric element <NUM> by accommodating the piezoelectric element <NUM>. In the present embodiment, the holding portions <NUM> are provided for each row of the piezoelectric elements <NUM>. More specifically, two holding portions <NUM> corresponding to the first pressure chamber row L1 and the second pressure chamber row L2 are formed to be adjacent to each other. The through hole <NUM> penetrates the sealing substrate <NUM> along the Z-axis direction. The through hole <NUM> is disposed between the two holding portions <NUM> in plan view, and is formed in a long rectangular shape along the Y-axis direction.

As illustrated in <FIG>, the case member <NUM> is fixed on the sealing substrate <NUM>. The case member <NUM> forms the manifold <NUM> that communicates with the plurality of pressure chambers <NUM>, together with the communication plate <NUM>. The case member <NUM> has substantially the same outer shape as the communication plate <NUM> in plan view, and is bonded to cover the sealing substrate <NUM> and the communication plate <NUM>.

The case member <NUM> includes an accommodation section <NUM>, a supply port <NUM>, a third manifold portion <NUM>, and a coupling port <NUM>. The accommodation section <NUM> is a space having a depth in which the pressure chamber substrate <NUM>, the vibration plate <NUM>, and the sealing substrate <NUM> can be accommodated. The third manifold portion <NUM> is a space provided in the vicinity of both ends of the accommodation section <NUM> in the X-axis direction in the case member <NUM>. The manifold <NUM> is formed by coupling the third manifold portion <NUM> to the first manifold portion <NUM> and the second manifold portion <NUM> provided in the communication plate <NUM>. The manifold <NUM> has a long shape in the Y-axis direction. The supply port <NUM> communicates with the manifold <NUM> to supply ink to each manifold <NUM>. The coupling port <NUM> is a through hole that communicates with the through hole <NUM> of the sealing substrate <NUM>, and the wiring substrate <NUM> is inserted to the coupling port <NUM>.

In the liquid ejecting head <NUM>, the ink supplied from the ink tank <NUM> illustrated in <FIG> is taken from the supply port <NUM> illustrated in <FIG>, and an internal flow path from the manifold <NUM> to the nozzle <NUM> is filled with ink. Thereafter, a voltage based on the drive signal is applied to each of the piezoelectric elements <NUM> corresponding to the plurality of pressure chambers <NUM>. Thereby, the vibration plate <NUM> bends and deforms together with the piezoelectric element <NUM>, and thus the internal pressure of each pressure chamber <NUM> increases because of a change in volume of each pressure chamber <NUM>. Therefore, ink droplets are ejected from each nozzle <NUM>.

Configurations of the piezoelectric element <NUM>, the humidity detection section <NUM>, and the temperature detection section <NUM> will be described with reference to <FIG> as appropriate together with reference to <FIG> and <FIG>. <FIG> is an enlarged explanatory diagram illustrating a partial range AR of <FIG>. <FIG> is a cross-sectional view illustrating a VII-VII position of <FIG>.

As illustrated in <FIG>, the piezoelectric element <NUM> includes a first drive electrode <NUM>, a piezoelectric body <NUM>, and a second drive electrode <NUM>. The first drive electrode <NUM>, the piezoelectric body <NUM>, and the second drive electrode <NUM> are laminated in this order in the -Z direction of the lamination direction. The piezoelectric body <NUM> is provided between the first drive electrode <NUM> and the second drive electrode <NUM> in the lamination direction.

As illustrated in <FIG>, the first drive electrode <NUM> and the second drive electrode <NUM> are electrically coupled to the wiring substrate <NUM> illustrated in <FIG> via a first drive wiring <NUM> and a second drive wiring <NUM>. The first drive electrode <NUM> and the second drive electrode <NUM> apply a voltage according to the drive signal to the piezoelectric body <NUM>. When a voltage is applied between the first drive electrode <NUM> and the second drive electrode <NUM>, a part, at which piezoelectric distortion occurs in the piezoelectric body <NUM>, in the piezoelectric element <NUM> is also referred to as an active portion.

A different drive voltage is applied to the first drive electrode <NUM> according to an ejection amount of ink, and a predetermined reference voltage is applied to the second drive electrode <NUM> regardless of the ejection amount of ink. When a voltage difference occurs between the first drive electrode <NUM> and the second drive electrode <NUM> because of the application of the drive voltage and the reference voltage, the piezoelectric body <NUM> of the piezoelectric element <NUM> is deformed. Because of the deformation of the piezoelectric body <NUM>, the vibration plate <NUM> is deformed or vibrated, and thus the volume of the pressure chamber <NUM> changes. Because of the change in the volume of the pressure chamber <NUM>, pressure is applied to the ink accommodated in the pressure chamber <NUM>, and thus the ink is ejected from the nozzle <NUM> via the nozzle communication path <NUM>.

In the present embodiment, the first drive electrode <NUM> is an individual electrode individually provided for the plurality of pressure chambers <NUM>. As illustrated in <FIG>, the first drive electrode <NUM> is a lower electrode provided on a side opposite to the second drive electrode <NUM> with the piezoelectric body <NUM> interposed therebetween, that is, on a lower side of the piezoelectric body <NUM>. A thickness of the first drive electrode <NUM> is formed to be, for example, approximately <NUM> nanometers. For example, the first drive electrode <NUM> is formed of a conductive material including a metal, such as platinum (Pt), iridium (Ir), gold (Au), titanium (Ti), and a conductive metal oxide such as indium tin oxide abbreviated as ITO. The first drive electrode <NUM> 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 for the first drive electrode <NUM>.

As illustrated in <FIG>, the piezoelectric body <NUM> has a predetermined width in the X-axis direction, and has a long rectangular shape along the arrangement direction of the pressure chambers <NUM>, that is, the Y-axis direction. The thickness of the piezoelectric body <NUM> is formed, for example, from approximately <NUM> nanometers to <NUM> nanometers. Examples of the piezoelectric body <NUM> include a crystal film having a perovskite structure provided on the first drive electrode <NUM> and made of a ferroelectric ceramic material exhibiting an electromechanical conversion action, that is, a so-called perovskite type crystal. As the material of the piezoelectric body <NUM>, for example, a ferroelectric piezoelectric material such as lead zirconate titanate (PZT) or a material to which a metal oxide, such as niobium oxide, nickel oxide, or magnesium oxide, is added can be used. Specifically, lead titanate (PbTiO<NUM>), lead zirconate titanate (Pb(Zr,Ti)O<NUM>), lead zirconate (PbZrO<NUM>), lead lanthanum titanate ((Pb,La),TiO<NUM>), lead lanthanum zirconate titanate ((Pb,La)(Zr,Ti)O<NUM>), lead magnesium niobate zirconate (Pb(Zr,Ti)(Mg,Nb)O<NUM>), or the like can be used. In the present embodiment, lead zirconate titanate (PZT) is used for the piezoelectric body <NUM>.

The material of the piezoelectric body <NUM> is not limited to the lead-based piezoelectric material containing lead, and a non-lead-based piezoelectric material containing no lead can also be used. Examples of the non-lead-based piezoelectric material include bismuth iron acid ((BiFeO<NUM>), abbreviated to "BFO"), barium titanate ((BaTiO<NUM>), abbreviated to "BT"), potassium sodium niobate ((K,Na)(NbO<NUM>), abbreviated to "KNN"), potassium sodium lithium niobate ((K,Na,Li) (NbO<NUM>)), potassium sodium lithium tantalate niobate ((K,Na,Li)(Nb,Ta)O<NUM>), bismuth potassium titanate ((Bi<NUM>/<NUM>K<NUM>/<NUM>)TiO<NUM>, abbreviated to "BKT"), bismuth sodium titanate ((Bi<NUM>/<NUM>Na<NUM>/<NUM>)TiO<NUM>, abbreviated to "BNT"), bismuth manganate (BiMnO<NUM>, abbreviated to "BM"), a composite oxide containing bismuth, potassium, titanium, and iron and having a perovskite structure (x[(BixK<NUM>-x)TiO<NUM>]-(<NUM>-X)[BiFeO<NUM>], abbreviated to "BKT-BF"), a composite oxide containing bismuth, iron, barium, and titanium and having a perovskite structure ((<NUM>-x)[BiFeO<NUM>]-x[BaTiO<NUM>], abbreviated to "BFO-BT"), and a material ((<NUM>-x)[Bi(Fe<NUM>-yMy)O<NUM>]-x[BaTiO<NUM>], M being Mn, Co, or Cr), which is obtained by adding metals such as manganese, cobalt, and chromium to the composite oxide.

As illustrated in <FIG>, the second drive electrode <NUM> is a common electrode that is commonly provided for the plurality of pressure chambers <NUM>. The second drive electrode <NUM> has a predetermined width in the X-axis direction, and is provided to extend along the arrangement direction of the pressure chambers <NUM>, that is, the Y-axis direction. As illustrated in <FIG>, the second drive electrode <NUM> is an upper electrode provided on a side opposite to the first drive electrode <NUM> with the piezoelectric body <NUM> interposed therebetween, that is, on an upper side of the piezoelectric body <NUM>. As a material of the second drive electrode <NUM>, similar to the first drive electrode <NUM>, for example, metals, such as platinum (Pt), iridium (Ir), gold (Au), and titanium (Ti), and conductive materials including conductive metal oxides, such as indium tin oxide abbreviated as ITO, are used. The second drive electrode <NUM> may be formed by laminating a plurality of materials such as platinum (Pt), iridium (Ir), gold (Au), and titanium (Ti). In the present embodiment, iridium (Ir) is used for the second drive electrode <NUM>.

As illustrated in <FIG>, a protective film <NUM> is provided on an end portion 80b of the second drive electrode <NUM> on the -X direction side. As a material of the protective film <NUM>, a material having an electrical insulating property and a moisture barrier property is used. For the protective film <NUM>, for example, an oxide insulating film such as aluminum oxide or hafnia, a polymer material film such as polyimide, or the like can be adopted. When the protective film <NUM> is a photosensitive resin such as polyimide, a resist layer used in a manufacturing process can be used. When the protective film <NUM> is made of a resin material, the surface resistance easily changes depending on the humidity, and thus the protective film <NUM> can be suitably used for an interlayer <NUM>. In the present embodiment, polyimide is used for the protective film <NUM>.

As illustrated in <FIG>, the protective film <NUM> is disposed at a drive electrode end portion position that overlaps the end portion 80b of the second drive electrode <NUM> in plan view of the liquid ejecting head <NUM>, and is formed to cover the end portion 80b and the surface of the piezoelectric body <NUM>. By covering the surface of the piezoelectric body <NUM> with the protective film <NUM>, the piezoelectric body <NUM> can be protected from moisture in the outside air and the air. Therefore, the protective film <NUM> is preferably made of a material having low water vapor permeability. Further, by covering the end portion 80b with the protective film <NUM>, peeling of the second drive electrode <NUM> from the end portion 80b can be suppressed or prevented. Further, by covering the end portion 80b, driving of the piezoelectric element <NUM> in the vicinity of the end portion of the active portion of the piezoelectric element <NUM> can be suppressed. As a result, for example, occurrence of a physical damage such as a crack in a member in the vicinity of the end portion of the active portion, such as a joint portion between the vibration plate <NUM> and the pressure chamber substrate <NUM> and the vibration plate <NUM>, can be suppressed. For this reason, the protective film <NUM> is preferably made of, for example, a material having a high elastic modulus or a high Young's modulus. For example, the Young's modulus is preferably equal to or higher than <NUM> GPa from a viewpoint of suitable driving suppression. Further, the protective film <NUM> has an insulating property, and thus a progress of migration between wirings such as wirings between the end portion 80b and the first drive wiring <NUM> or the like can be suppressed or prevented. When the second drive electrode <NUM> is disposed on the lower side of the piezoelectric body <NUM> as a lower electrode and the first drive electrode <NUM> is disposed on the upper side of the piezoelectric body <NUM> as an upper electrode, the drive electrode end portion position means a position overlapping the end portion of the first drive electrode <NUM> on the -X direction side. On the other hand, the drive electrode end portion position is not limited to only the end portion of the first drive electrode <NUM> on the -X direction side, and may be set by using an end portion located in any direction of the first drive electrode <NUM> or the second drive electrode <NUM>, or by using a plurality of end portions obtained by combining end portions of the first drive electrode <NUM> and the second drive electrode <NUM>.

As illustrated in <FIG>, a wiring portion <NUM> is provided on the further -X direction side of the end portion 80b of the second drive electrode <NUM> in the -X direction. The wiring portion <NUM> is in the same layer as the second drive electrode <NUM>, but is electrically discontinuous with the second drive electrode <NUM>. The wiring portion <NUM> is formed from the end portion 70b of the piezoelectric body <NUM> in the -X direction to the end portion 60b of the first drive electrode <NUM> in the -X direction in a state of being spaced from the end portion 80b of the second drive electrode <NUM>. The end portion 60b of the first drive electrode <NUM> in the -X direction is pulled out from the end portion 70b of the piezoelectric body <NUM> to the outside. The wiring portion <NUM> is provided for each piezoelectric element <NUM>, and a plurality of wiring portions <NUM> are disposed at predetermined intervals along the Y-axis direction. Preferably, the wiring portion <NUM> is formed in the same layer as the second drive electrode <NUM>. Thereby, a manufacturing process of the wiring portion <NUM> can be simplified and the cost can be reduced. Here, the wiring portion <NUM> may be formed in a layer different from the layer of the second drive electrode <NUM>.

As illustrated in <FIG> and <FIG>, the first drive wiring <NUM> is electrically coupled to the first drive electrode <NUM> which is an individual electrode, and an extension portion 92a and an extension portion 92b of the second drive wiring <NUM> are electrically coupled to the second drive electrode <NUM> which is a common electrode. The first drive wiring <NUM> and the second drive wiring <NUM> function as drive wirings for applying a voltage for driving the piezoelectric body <NUM> from the wiring substrate <NUM>.

The materials of the first drive wiring <NUM> and the second drive wiring <NUM> are conductive materials. For example, gold (Au), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), platinum (Pt), aluminum (Al), and the like can be used. In the present embodiment, gold (Au) is used for the first drive wiring <NUM> and the second drive wiring <NUM>. The first drive wiring <NUM> and the second drive wiring <NUM> are formed in the same layer to be electrically discontinuous with each other. Thereby, a process of forming the first drive wiring <NUM> can be shared with a process of forming the second drive wiring <NUM>. Therefore, as compared with when the first drive wiring <NUM> and the second drive wiring <NUM> are individually formed, the manufacturing process can be simplified and productivity of the liquid ejecting head <NUM> can be improved. Here, the first drive wiring <NUM> and the second drive wiring <NUM> may be formed in different layers instead of being formed in the same layer. In addition, the first drive wiring <NUM> and the second drive wiring <NUM> may include an adhesion layer for improving adhesion to the first drive electrode <NUM>, the second drive electrode <NUM>, and the vibration plate <NUM>.

The first drive wiring <NUM> is individually provided for each first drive electrode <NUM>. As illustrated in <FIG>, the first drive wiring <NUM> is coupled to the vicinity of the end portion 60b of the first drive electrode <NUM> via the wiring portion <NUM>, and is pulled out in the -X direction to reach a top of the vibration plate <NUM>. The first drive wiring <NUM> is electrically coupled to the end portion 60b of the first drive electrode <NUM> in the -X direction, the end portion 60b being pulled out from the end portion 70b of the piezoelectric body <NUM> to the outside. The wiring portion <NUM> may be omitted, and the first drive wiring <NUM> may be directly coupled to the end portion 60b of the first drive electrode <NUM>.

As illustrated in <FIG>, the second drive wiring <NUM> extends along the Y-axis direction, bends at both ends in the Y-axis direction, and is pulled out along the X-axis direction. The second drive wiring <NUM> includes an extension portion 92a extending along the Y-axis direction and an extension portion 92b. As illustrated in <FIG> and <FIG>, the end portions of the first drive wiring <NUM> and the second drive wiring <NUM> are extended so as to be exposed to the through hole <NUM> of the sealing substrate <NUM>, and are electrically coupled to the wiring substrate <NUM> in the through hole <NUM>.

The wiring substrate <NUM> is configured with, for example, a flexible printed circuit (FPC). The wiring substrate <NUM> is provided with a plurality of wirings for coupling to the control device <NUM> and a power supply circuit (not illustrated). In addition, the wiring substrate <NUM> may be configured with any flexible substrate, such as flexible flat cable (FFC), instead of FPC. An integrated circuit <NUM> including a switching element and the like is mounted at the wiring substrate <NUM>. A command signal or the like for driving the piezoelectric element <NUM> is input to the integrated circuit <NUM>. The integrated circuit <NUM> controls a timing at which a drive signal for driving the piezoelectric element <NUM> is supplied to the first drive electrode <NUM> based on the command signal.

As illustrated in <FIG>, the temperature detection section <NUM> includes a temperature detection resistor <NUM> and temperature detection wirings <NUM>. The temperature detection resistor <NUM> is a resistance wiring used for detecting the temperature of the ink in the pressure chamber. The temperature detection wiring <NUM> electrically couples the wiring substrate <NUM> and the temperature detection resistor <NUM>. More specifically, the temperature detection wirings <NUM> include a first temperature detection wiring <NUM> coupled to one end of the temperature detection resistor <NUM> and a second temperature detection wiring <NUM> coupled to the other end of the temperature detection resistor <NUM>. The temperature detection wirings <NUM> are formed in the same layer as, for example, layers of the first drive wiring <NUM>, the second drive wiring <NUM>, and a humidity detection wiring <NUM> to be described later, and are formed so as to be electrically discontinuous with each other. An end portion of the temperature detection wiring <NUM> extends so as to be exposed to the through hole <NUM> of the sealing substrate <NUM>, and is electrically coupled to the wiring substrate <NUM> in the through hole <NUM>.

A material of the temperature detection resistor <NUM> is a material of which the resistance value is temperature dependent. For example, gold (Au), platinum (Pt), iridium (Ir), aluminum (Al), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), or the like may be used. Here, platinum (Pt) can be preferably used as a material of the temperature detection resistor <NUM> from a viewpoint that the change in resistance with temperature is large and stability and accuracy are high.

As illustrated in <FIG>, the temperature detection resistor <NUM> is formed in the same layer as, for example, the layer of the first drive electrode <NUM> in the lamination direction, and is formed so as to be electrically discontinuous with the first drive electrode <NUM>. In the present embodiment, the temperature detection resistor <NUM> is formed together with the first drive electrode <NUM> in a process of forming the first drive electrode <NUM>. As a result, the temperature detection resistor <NUM> is formed of platinum (Pt), which is the same material as the first drive electrode <NUM>, and a thickness of the temperature detection resistor <NUM> is approximately <NUM> nanometers similar to the first drive electrode <NUM>. Here, the temperature detection resistor <NUM> is not limited thereto, may be individually formed separately from the first drive electrode <NUM>, or may be formed together with a conductor wiring different from the conductor wiring of the first drive electrode <NUM>.

A material of the temperature detection wiring <NUM> is a conductive material. For example, gold (Au), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), platinum (Pt), aluminum (Al), and the like can be used. The material of the temperature detection wiring <NUM> is gold (Au) that is the same as the materials of the first drive wiring <NUM>, the second drive wiring <NUM>, and the humidity detection wiring <NUM>. Here, any material other than gold (Au) may be used for the temperature detection wiring <NUM>, and the material may be different from the materials of the first drive wiring <NUM>, the second drive wiring <NUM>, and the humidity detection wiring <NUM>.

As illustrated in <FIG>, in the present embodiment, the temperature detection resistor <NUM> is continuously formed so as to surround the vicinities of the first pressure chamber row L1 and the second pressure chamber row L2 in plan view. More specifically, the temperature detection resistor <NUM> includes a first extension portion 415A electrically coupled to the first temperature detection wiring <NUM>, a third extension portion 415C electrically coupled to the second temperature detection wiring <NUM>, and second extension portions 415B between the first extension portion 415A and the third extension portion 415C.

The first extension portion 415A extends along the X-axis direction, which is the intersection direction, on one side in the arrangement direction of the plurality of pressure chambers <NUM>, specifically, on the -Y direction side. The second extension portion 415B is further disposed on an outer side with respect to the first pressure chamber row L1 and the second pressure chamber row L2 in the liquid ejecting head <NUM>, and extends along the Y-axis direction which is the arrangement direction. The third extension portion 415C extends along the X-axis direction, at a position on the other side in the arrangement direction of the plurality of pressure chambers <NUM>, specifically, the +Y direction side. In this way, the temperature detection resistor <NUM> is disposed so as to surround the vicinities of the first pressure chamber row L1 and the second pressure chamber row L2. By widening a region in which the temperature detection resistor <NUM> is disposed, the temperature of the entire ink of the liquid ejecting head <NUM> can be detected.

As illustrated in <FIG> and <FIG>, the temperature detection resistor <NUM> is disposed so as to pass the vicinity of the ink flow path in the pressure chamber substrate <NUM>. More specifically, the second extension portion 415B of the temperature detection resistor <NUM> is disposed so as to pass the throttle portion <NUM> in the vicinity of each pressure chamber <NUM>. In addition, as illustrated in <FIG>, the second extension portion 415B is formed as a so-called zigzag pattern to be reciprocated a plurality of times along the arrangement direction. By lengthening a wiring length of the portion of the temperature detection resistor <NUM> that passes the vicinity of the pressure chamber <NUM> and is likely to contribute to the temperature detection of the ink, accuracy in detection of the temperature of the ink in the pressure chamber <NUM> can be improved. Here, the second extension portion 415B may be formed, for example, in a zigzag pattern to be reciprocated a plurality of times along the intersection direction instead of the arrangement direction, or may be formed, for example, in any shape such as a linear shape or a wave shape instead of the zigzag pattern. Further, the disposition position of the temperature detection resistor <NUM> is not limited to the position on the throttle portion <NUM>, and may be any position on the pressure chamber <NUM>. When the temperature detection resistor <NUM> cannot be disposed on the pressure chamber <NUM>, the temperature detection resistor <NUM> may be disposed at a position close to the pressure chamber <NUM>.

As illustrated in <FIG>, in plan view, the humidity detection sections <NUM> are disposed at total four positions including positions adjacent to both sides of the first pressure chamber row L1 along the first arrangement direction and positions adjacent to both sides of the second pressure chamber row L2 along the second arrangement direction. The humidity detection sections <NUM> are individually provided for each of the holding portions <NUM> of the sealing substrate <NUM> corresponding to the first pressure chamber row L1 and the holding portion <NUM> of the sealing substrate <NUM> corresponding to the second pressure chamber row L2. Thereby, information on the humidity of each pressure chamber row can be acquired with high accuracy. Here, the positions of the humidity detection sections <NUM> are not limited to the four positions. The humidity detection sections <NUM> may be disposed at least any one position of positions adjacent to the first pressure chamber row L1 on the +Y direction side and the -Y direction side and positions adjacent to the second pressure chamber row L2 on the +Y direction side and the -Y direction side in the second arrangement direction. Here, preferably, the humidity detection sections <NUM> are formed in a number corresponding to the number of the holding portions <NUM>.

As illustrated in <FIG>, the humidity detection section <NUM> includes humidity detection wirings <NUM>, a first detection electrode <NUM>, a second detection electrode <NUM>, and an interlayer <NUM>. The interlayer <NUM> is a humidity detection target, and is formed of a material of which the resistance changes with humidity. For the interlayer <NUM>, among the members included in the liquid ejecting head <NUM>, as a member of which the performance may deteriorate because of the influence of the humidity, a member to be laminated on at least one of the piezoelectric body <NUM>, the vibration plate <NUM>, or the pressure chamber substrate <NUM> can be adopted. In the present embodiment, the same material as the material of the protective film <NUM> is used for the interlayer <NUM>. In the present embodiment, the interlayer <NUM> is provided on the surface of the piezoelectric body <NUM> together with the protective film <NUM> in the process of forming the protective film <NUM>. By sharing the process of forming the interlayer <NUM> with the process of forming the protective film <NUM>, productivity of the liquid ejecting head <NUM> can be improved. The interlayer <NUM> may be doped with a metal such as chromium (Cr) by ion filling or the like such that a current for humidity detection is likely to flow.

The humidity detection wirings <NUM> include a first humidity detection wiring <NUM> that electrically couples the wiring substrate <NUM> and the first detection electrode <NUM> and a second humidity detection wiring <NUM> that electrically couples the wiring substrate <NUM> and the second detection electrode <NUM>. End portions of the first humidity detection wiring <NUM> and the second humidity detection wiring <NUM> extend so as to be exposed to the through hole <NUM> of the sealing substrate <NUM>, and are electrically coupled to the wiring substrate <NUM> in the through hole <NUM>.

A material of the humidity detection wiring <NUM> is a conductive material. For example, gold (Au), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), platinum (Pt), aluminum (Al), and the like can be used. The material of the humidity detection wiring <NUM> is gold (Au) that is the same as the materials of the first drive wiring <NUM>, the second drive wiring <NUM>, and the temperature detection wiring <NUM>. Here, any material other than gold (Au) may be used for the humidity detection wiring <NUM>, and the material may be different from the materials of the first drive wiring <NUM>, the second drive wiring <NUM>, and the temperature detection wiring <NUM>.

The first detection electrode <NUM> and the second detection electrode <NUM> are formed in the same layer without being in direct contact with each other so as to be electrically discontinuous to each other. The first detection electrode <NUM> and the second detection electrode <NUM> are provided on the interlayer <NUM> to be in contact with the interlayer <NUM> in order to allow the current from the humidity-detection power supply section <NUM>, which is a constant current circuit, to flow on the surface of the interlayer <NUM>. "current flows through the interlayer <NUM>" includes that a current flows through the inside of the interlayer <NUM>, the surface of the interlayer <NUM>, and a boundary surface between the interlayer <NUM> and another layer.

<FIG> is a cross-sectional view illustrating a VIII-VIII position of <FIG>. In the present embodiment, as illustrated in <FIG>, the first detection electrode <NUM> and the second detection electrode <NUM> are disposed on the other side of the lamination direction with respect to the interlayer <NUM>, that is, on the upper surface of the interlayer <NUM>. The surface of the interlayer <NUM> is exposed between the first detection electrode <NUM> and the second detection electrode <NUM>, and the current from the first detection electrode <NUM> and the second detection electrode <NUM> may flow on the surface of the interlayer <NUM>. Thereby, the resistance of the surface of the protective film <NUM> can be detected. Therefore, a temporal change in the moisture absorption state of the protective film <NUM> can be managed, and a temporal change in the performance of the protective film <NUM> because of humidity can be managed.

The first detection electrode <NUM> and the second detection electrode <NUM> can be formed in any shape. In the present embodiment, the first detection electrode <NUM> and the second detection electrode <NUM> adopt a so-called comb shape suitable for evaluation of insulation deterioration because of ion migration or the like, and are disposed so as to face each other on the surface of the interlayer <NUM>. More specifically, as illustrated in <FIG>, the first detection electrode <NUM> includes a first electrode portion 211P1 extending along a certain first direction and a plurality of second electrode portions 211P2 coupled to the first electrode portion 211P1. The plurality of second electrode portions 211P2 extend along a second direction intersecting with the first direction, and are arranged to be separated from each other. In the example of <FIG>, the first direction coincides with the X-axis direction, and the second direction coincides with the Y-axis direction.

Similarly, the second detection electrode <NUM> includes a third electrode portion 212P3 extending along a certain third direction and a plurality of fourth electrode portions 212P4 coupled to the third electrode portion 212P3. The fourth electrode portions 212P4 extend along a fourth direction intersecting with the third direction, and are disposed to be separated from each other. In the example of <FIG>, the third direction coincides with the X-axis direction, and is parallel to the first direction. The fourth direction coincides with the Y-axis direction, and is parallel to the second direction. As illustrated in <FIG>, the plurality of second electrode portions 211P2 and the plurality of fourth electrode portions 212P4 are alternately disposed. A distance between the plurality of second electrode portions 211P2 and the plurality of fourth electrode portions 212P4 is preferably close enough to be suitable for migration evaluation, and is preferably constant regardless of location.

The first detection electrode <NUM> and the second detection electrode <NUM> can be formed of any conductive material, and can be formed of, for example, a conductive material such as a metal, such as platinum (Pt), iridium (Ir), gold (Au), and titanium (Ti), or a conductive metal oxide such as indium tin oxide which is abbreviated as ITO. The first detection electrode <NUM> and the second detection electrode <NUM> may be formed by laminating a plurality of materials such as platinum (Pt), iridium (Ir), gold (Au), and titanium (Ti). The first detection electrode <NUM> and the second detection electrode <NUM> may be made of the same material or different materials from each other.

In the present embodiment, the same iridium (Ir) as the material of the second drive electrode <NUM> is used for the first detection electrode <NUM> and the second detection electrode <NUM>. By sharing the process of forming the first detection electrode <NUM> and the second detection electrode <NUM> with the process of forming the second drive electrode <NUM>, productivity of the liquid ejecting head <NUM> can be improved. For the first detection electrode <NUM> and the second detection electrode <NUM>, for example, gold (Au), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), platinum (Pt), aluminum (Al), or the like can also be used. The materials of the first detection electrode <NUM> and the second detection electrode <NUM> can be the same as the materials of the first drive wiring <NUM>, the second drive wiring <NUM>, the temperature detection wiring <NUM>, and the humidity detection wiring <NUM>. As an example of the process order when sharing the process of forming the first detection electrode <NUM> and the second detection electrode <NUM> with the process of forming the second drive electrode <NUM>, first, the interlayer <NUM> is formed using the same material as the material of the protective film <NUM>, and the first detection electrode <NUM>, the second detection electrode <NUM>, and the second drive electrode <NUM> are formed in the same process. Thereafter, the protective film <NUM> is formed at the drive electrode end portion position.

As described above, the liquid ejecting head <NUM> of the present embodiment includes the interlayer <NUM> which is laminated on the piezoelectric body <NUM> and of which the resistance changes according to humidity, the first detection electrode <NUM> which is in contact with the interlayer <NUM>, and the second detection electrode <NUM> which is in contact with the interlayer <NUM>, the second detection electrode <NUM> being disposed so as to face the first detection electrode <NUM>. With the liquid ejecting head <NUM> configured as described above, by using the resistance between the first detection electrode <NUM> and the second detection electrode <NUM>, the information on the humidity of the interlayer <NUM>, which is laminated on the piezoelectric body <NUM> among the component members of the liquid ejecting head <NUM>, can be detected with high accuracy. Therefore, the influence of the humidity on the piezoelectric element <NUM> or the member in the vicinity of the piezoelectric element <NUM> can be appropriately managed.

With the liquid ejecting head <NUM> of the present embodiment, the first detection electrode <NUM> and the second detection electrode <NUM> are disposed on the surface of the interlayer <NUM>, and the surface of the interlayer <NUM> is exposed between the first detection electrode <NUM> and the second detection electrode <NUM>. With the liquid ejecting head <NUM> configured as described above, the resistance of the surface of the interlayer <NUM> can be detected, and thus a temporal change in the performance of the interlayer <NUM> because of humidity can be evaluated.

The liquid ejecting apparatus <NUM> of the present embodiment includes, in addition to the liquid ejecting head <NUM>, the humidity-detection resistance measurement section <NUM> that measures the resistance between the first detection electrode <NUM> and the second detection electrode <NUM> and the humidity management section <NUM> that acquires information on the humidity of the interlayer <NUM> by using the resistance measured by the humidity-detection resistance measurement section <NUM>. Therefore, the liquid ejecting apparatus <NUM> that can appropriately manage the information on the humidity in the member in the liquid ejecting head <NUM> can be provided.

With the liquid ejecting head <NUM> of the present embodiment, the first detection electrode <NUM> and the second detection electrode <NUM> are formed of the same material as the material of the second drive electrode <NUM>. The process of forming the first detection electrode <NUM> and the second detection electrode <NUM> can be shared with the process of forming the second drive electrode <NUM>, and thus productivity of the liquid ejecting head <NUM> can be improved.

The liquid ejecting head <NUM> of the present embodiment further includes the protective film <NUM> that is disposed on an upper side of the pressure chamber substrate <NUM>, more specifically, at the end portion 80b of the second drive electrode <NUM> and on the surface of the piezoelectric body <NUM>, and is formed using a resin material. The interlayer <NUM> is formed of the same material as the material of the protective film <NUM>. By forming the interlayer <NUM> using a resin material of which surface resistance is likely to change according to humidity, accuracy of detection of the information on humidity can be improved. Further, by sharing the process of forming the interlayer <NUM> with the process of forming the protective film <NUM>, productivity of the liquid ejecting head <NUM> can be improved.

With the liquid ejecting head <NUM> of the present embodiment, the first detection electrode <NUM> and the second detection electrode <NUM> are disposed in the same layer on the upper side of the interlayer <NUM>. By forming the first detection electrode <NUM> and the second detection electrode <NUM> in the same layer, the process of forming the first detection electrode <NUM> and the process of forming the second detection electrode <NUM> can be easily shared. Further, by detecting the resistance on the surface that is likely to be influenced by moisture absorption, accuracy of detection of humidity can be improved as compared with when the first detection electrode <NUM> and the second detection electrode <NUM> are provided on the inside.

With the liquid ejecting head <NUM> of the present embodiment, the humidity detection sections <NUM> are disposed at positions adjacent to both sides of the first pressure chamber row L1 along the first arrangement direction and positions adjacent to both sides of the second pressure chamber row L2 along the second arrangement direction. With the liquid ejecting head <NUM> configured as described above, by individually providing the humidity detection sections <NUM> for each of the holding portions <NUM> of the first pressure chamber row L1 and the second pressure chamber row L2, the information on humidity for each pressure chamber row can be acquired with high accuracy.

<FIG> is a first explanatory diagram illustrating the humidity detection section 210a1 included in the liquid ejecting head of another embodiment. The first embodiment describes an example in which the first detection electrode <NUM> and the second detection electrode <NUM> are disposed on the other side of the lamination direction with respect to the interlayer <NUM>, that is, on the upper side of the interlayer <NUM>. On the other hand, as in the humidity detection section 210a1 illustrated in <FIG>, the first detection electrode <NUM> and the second detection electrode <NUM> may be disposed in the same layer on the lower side of the interlayer <NUM>. Even in such a configuration, as in the first embodiment, the information on the humidity of the interlayer <NUM> can be detected with high accuracy, and the influence of the humidity on the piezoelectric element <NUM> or the member in the vicinity of the piezoelectric element <NUM> can be appropriately managed.

In the example of <FIG>, the first detection electrode <NUM> and the second detection electrode <NUM> are provided on the upper side of the piezoelectric body <NUM>, and are disposed at a boundary surface between the piezoelectric body <NUM> and the interlayer <NUM>. In this case, an influence of humidity on the layer on the upper side of the boundary surface, that is, an influence of humidity on the interlayer <NUM> in the example of <FIG> can be acquired. It is considered that this is because the current flowing between the first detection electrode <NUM> and the second detection electrode <NUM> is more likely to flow to the lower surface of the interlayer <NUM> of which density is more likely to be lower than density of the piezoelectric body <NUM>. It is considered that the reason why the density is likely to be lower at a position on the lower surface of the interlayer <NUM>, that is, a position in the +Z direction from a center of the interlayer in the Z-axis direction is that the interlayer <NUM> which is an upper layer is likely to be influenced by a crystal structure of the piezoelectric body <NUM> which is a lower layer provided in advance when the interlayer <NUM> is laminated.

<FIG> is a second explanatory diagram illustrating the humidity detection section 210a2 included in the liquid ejecting head of another embodiment. The first embodiment describes an example in which the first detection electrode <NUM> and the second detection electrode <NUM> are disposed in the same layer. On the other hand, as in the humidity detection section 210a2 illustrated in <FIG>, the first detection electrode 211a2 and the second detection electrode 212a2 may be disposed in different layers. In the example of <FIG>, the first detection electrode 211a2 is disposed on the lower side of the interlayer <NUM>, and the second detection electrode 212a2 is disposed on the upper side of the interlayer <NUM>. In this case, for example, the process of forming the first detection electrode 211a2 is shared with the process of forming the second drive electrode <NUM>, and the first detection electrode 211a2 is provided on the piezoelectric body <NUM>. After the interlayer <NUM> is formed using the same material as the material of the protective film <NUM>, the process of forming the second detection electrode 212a2 is shared with the process of forming the first drive wiring <NUM>, the second drive wiring <NUM>, the temperature detection wiring <NUM>, or the humidity detection wiring <NUM>, and the second detection electrode 212a2 is provided on the interlayer <NUM>. With the liquid ejecting head configured as described above, by detecting interfacial resistance of the interlayer <NUM>, information on humidity of the interlayer <NUM> can be detected with high accuracy.

The first embodiment describes an example in which the first detection electrode <NUM> and the second detection electrode <NUM> have a comb shape. On the other hand, as illustrated in <FIG>, the first detection electrode 211a2 and the second detection electrode 212a2 may have shapes other than the comb shape. In the example of <FIG>, both the first detection electrode 211a2 and the second detection electrode 212a2 are formed in a flat plate shape. The first detection electrode 211a2 and the second detection electrode 212a2 are both in contact with the interlayer <NUM>, and are disposed so as to face each other with the interlayer <NUM> interposed therebetween. With the liquid ejecting head configured as described above, interfacial resistance between the interlayer <NUM> and the first detection electrode 211a2 and the second detection electrode 212a2 can be detected, and thus information on humidity of the interlayer <NUM> can be detected with high accuracy. For the first detection electrode 211a2 and the second detection electrode 212a2, various shapes for general resistance measurement can be adopted. In addition to the flat plate shape, the first detection electrode 211a2 and the second detection electrode 212a2 may have, for example, a shape in which a certain number of through holes having a certain shape are provided in a comb shape. In addition to the comb shape, a so-called zigzag shape in which the conductor zigzags may be adopted.

Since the second detection electrode 212a2 is formed to cover the upper surface of the interlayer <NUM>, an exposed area of the interlayer <NUM> is reduced. As a result, moisture absorption and dehumidification of the interlayer <NUM> may be inhibited, and detection accuracy may be lowered. Therefore, from a viewpoint of suppressing inhibition of moisture absorption and dehumidification of the interlayer <NUM>, preferably, the second detection electrode 212a2 is formed in a shape with an area smaller than an area of a flat plate shape, such as a comb shape, such that the upper surface of the interlayer <NUM> can be exposed.

<FIG> is an explanatory diagram illustrating a configuration of a liquid ejecting head 510b according to a second embodiment of the present disclosure in plan view. The liquid ejecting head 510b of the present embodiment is different in that a humidity detection section 210b is provided instead of the humidity detection section <NUM>, and the other configurations are the same as the configurations of the liquid ejecting head <NUM> of the first embodiment.

<FIG> is an enlarged explanatory diagram illustrating a partial range AR of <FIG>. The humidity detection section 210b is different from the humidity detection section <NUM> described in the first embodiment in that the material used for the interlayer is different. More specifically, in the first embodiment, the same material as the material of the protective film <NUM> is used for the interlayer <NUM>. On the other hand, in the present embodiment, the same material as the material of the piezoelectric body <NUM> is used for the interlayer 215b. As illustrated in <FIG>, the disposition position of the humidity detection section 210b and the shapes of the first detection electrode 211b and the second detection electrode 212b in plan view are the same as those in the first embodiment.

<FIG> is a cross-sectional view illustrating an XIII-XIII position of <FIG>. As illustrated in <FIG>, the present embodiment is different from the first embodiment in that the first detection electrode 211b and the second detection electrode 212b are disposed on the lower side of the piezoelectric body <NUM> which is the interlayer 215b. More specifically, the first detection electrode 211b and the second detection electrode 212b are provided on the vibration plate <NUM>, and are disposed between the vibration plate <NUM> and the piezoelectric body <NUM>.

In the present embodiment, the first detection electrode 211b and the second detection electrode 212b are formed of the same material as the material of the first drive electrode <NUM>. In addition, the process of forming the first detection electrode 211b and the second detection electrode 212b is shared with the process of forming the first drive electrode <NUM>, and when forming the first drive electrode <NUM> at the vibration plate <NUM>, the first detection electrode 211b and the second detection electrode 212b are also formed. After the first detection electrode 211b and the second detection electrode 212b are formed, the piezoelectric body <NUM> is laminated in a range including the first detection electrode 211b and the second detection electrode 212b.

The first detection electrode 211b and the second detection electrode 212b are not limited to being disposed on the lower side of the piezoelectric body <NUM>, and can be disposed on the upper surface of the piezoelectric body <NUM> in a state of being exposed. In this case, the process of forming the first detection electrode 211b and the second detection electrode 212b may be shared with the process of forming the second drive electrode <NUM>, and the first detection electrode 211b and the second detection electrode 212b can be formed together with the second drive electrode <NUM> after the piezoelectric body <NUM> is formed.

As described above, the liquid ejecting head 510b of the second embodiment includes the piezoelectric body <NUM> which is laminated on the vibration plate <NUM>, of which the resistance changes according to humidity, and which is the interlayer 215b. With the liquid ejecting head 510b configured as described above, the information on humidity of the piezoelectric body <NUM> can be detected with high accuracy, and thus an influence of the humidity on the piezoelectric element <NUM> can be appropriately managed.

With the liquid ejecting head 510b of the present embodiment, the first detection electrode 211b and the second detection electrode 212b are formed of the same material as the material of the first drive electrode <NUM>. With the configuration, the process of forming the first detection electrode 211b and the second detection electrode 212b can be shared with the process of forming the first drive electrode <NUM>, and thus productivity of the liquid ejecting head 510b can be improved.

With the liquid ejecting head 510b of the present embodiment, the first detection electrode 211b and the second detection electrode 212b are disposed in the same layer on the lower side of the interlayer <NUM> which is formed of the same material as the material of the piezoelectric body <NUM>. By forming the first detection electrode 211b and the second detection electrode 212b in the same layer, the process of forming the first detection electrode 211b and the process of forming the second detection electrode 212b can be easily shared. Further, by forming the first detection electrode 211b and the second detection electrode 212b on the lower side of the piezoelectric body <NUM>, the process of forming the first detection electrode 211b and the second detection electrode 212b can be easily shared with the process of forming the first drive electrode <NUM>.

<FIG> is a third explanatory diagram illustrating the humidity detection section 210b2 included in the liquid ejecting head of another embodiment. The second embodiment describes an example in which the first detection electrode 211b and the second detection electrode 212b are disposed in the same layer on the lower side of the piezoelectric body <NUM>. On the other hand, as in the humidity detection section 210b2 illustrated in <FIG>, the first detection electrode 211b2 and the second detection electrode 212b2 may be disposed in different layers. In the example of <FIG>, the first detection electrode 211b2 has a flat plate shape, and is disposed on the lower side of the piezoelectric body <NUM> which serves as the interlayer <NUM>. The second detection electrode 212b2 has a flat plate shape, and is disposed on the upper side of the piezoelectric body <NUM>. With the liquid ejecting head configured as described above, by detecting interfacial resistance of the piezoelectric body <NUM>, an influence of humidity on the piezoelectric body <NUM> can be appropriately managed. In addition, for example, the process of forming the first detection electrode 211b2 can be shared with the process of forming the first drive electrode <NUM>. Further, the process of forming the second detection electrode 212b2 can be shared with the process of forming the second drive electrode <NUM> after the piezoelectric body <NUM> is coated. From a viewpoint of suppressing inhibition of moisture absorption of the piezoelectric body <NUM> which serves as the interlayer 215b, preferably, the second detection electrode 212b2 is formed in a shape with an area smaller than an area of a flat plate shape, such as a comb shape, such that the upper surface of the piezoelectric body <NUM> is exposed.

<FIG> is an explanatory diagram illustrating a configuration of a liquid ejecting head 510c according to a third embodiment of the present disclosure in plan view. The liquid ejecting head 510c of the present embodiment is different in that a humidity detection section 210c is provided instead of the humidity detection section <NUM>, and the other configurations are the same as the configurations of the liquid ejecting head <NUM> of the first embodiment.

The humidity detection section 210c is different from the humidity detection section <NUM> described in the first embodiment in that a material used for the interlayer 215c is different and that an insulating portion <NUM> is further provided. In <FIG>, in order to facilitate understanding of the technique, the insulating portion <NUM> is hatched. In the present embodiment, the same material as the material of the vibration plate <NUM> is used for the interlayer 215c. As illustrated in <FIG>, the disposition position of the humidity detection section 210c in plan view is the same as the disposition position in the first embodiment.

<FIG> is a cross-sectional view illustrating an XVI-XVI position of <FIG>. The interlayer 215c includes a first interlayer, a second interlayer laminated on the first interlayer, and a boundary surface between the first interlayer and the second interlayer. In the present embodiment, assuming that the elastic film <NUM> of the vibration plate <NUM> is referred to as a "first layer" and the insulator film <NUM> laminated on the elastic film <NUM> is referred to as a "second layer", the first layer functions as the first interlayer, and the second layer functions as the second interlayer.

As illustrated in <FIG>, the first detection electrode 211c and the second detection electrode 212c are disposed at recessed portions 50R1 and 50R2 formed in the vibration plate <NUM> which serves as the interlayer 215c. The recessed portion 50R1 corresponds to a formation position of the first detection electrode 211c, and the recessed portion 50R2 corresponds to a formation position of the second detection electrode 212c. In plan view, the first detection electrode 211c and the second detection electrode 212c are formed so as to have a comb shape illustrated in <FIG>.

As illustrated in <FIG>, in a cross-sectional view, the recessed portions 50R1 and 50R2 are deeper than a boundary surface 50IN between the elastic film <NUM> and the insulator film <NUM>, and are formed by, for example, etching the vibration plate <NUM> from the surface of the elastic film <NUM> to a part of the insulator film <NUM> by ion milling or the like. The first detection electrode 211c and the second detection electrode 212c are disposed in the recessed portions 50R1 and 50R2 on both sides of the boundary surface 50IN so as to be in contact with the boundary surface 50IN, and detect resistance of the boundary surface 50IN. Thereby, information on humidity of the insulator film <NUM> which is the upper layer of the vibration plate <NUM> can be detected with high accuracy.

In the present embodiment, the first detection electrode 211c and the second detection electrode 212c are formed of the same material as the material of the second drive electrode <NUM>. For example, the humidity detection section 210c is provided on the exposed vibration plate <NUM> obtained by forming a film of the piezoelectric body <NUM> once and removing the film by etching. Therefore, the process of forming the first detection electrode 211c and the second detection electrode 212c can be shared with the process of forming the second drive electrode <NUM> that is a process after a film of the piezoelectric body <NUM> is formed, and thus productivity can be increased. Here, the present disclosure is not limited thereto. The first detection electrode 211c and the second detection electrode 212c may be formed in the process of forming the first drive electrode <NUM> before the piezoelectric body <NUM> is formed, and may be formed in another process such as the process of forming the first drive wiring <NUM>, the second drive wiring <NUM>, the temperature detection wiring <NUM>, the humidity detection wiring <NUM>, or the like.

The insulating portion <NUM> is disposed between the first detection electrode 211c and the second detection electrode 212c on an upper surface of the insulator film <NUM>. As a material of the insulating portion <NUM>, a material having an electrical insulating property and a moisture barrier property is used. Thereby, short circuit between the first detection electrode 211c and the second detection electrode 212c on the surface of the insulator film <NUM> is suppressed or prevented. The insulating portion <NUM> can be formed of the same material as the material of the protective film <NUM>, for example, an oxide insulating film such as aluminum oxide or Hafnia, or a polymer material film such as polyimide. When the insulating portion <NUM> is a photosensitive resin such as polyimide, a resist layer used in a manufacturing process can be used. When the first detection electrode 211c and the second detection electrode 212c are sufficiently insulated, the insulating portion <NUM> may be omitted.

As described above, with the liquid ejecting head 510c of the third embodiment, the interlayer 215c includes the first interlayer, the second interlayer laminated on the first interlayer, and the boundary surface between the first interlayer and the second interlayer. The boundary surface is disposed between the first detection electrode <NUM> and the second detection electrode <NUM>. Therefore, even when the interlayer 215c is formed by laminating two layers, by acquiring the resistance of the boundary surface of the interlayer 215c, an influence of humidity on the interlayer 215c can be appropriately managed.

With the liquid ejecting head 510c of the present embodiment, the interlayer 215c is formed of the same material as the material of the vibration plate <NUM>. Thus, information on humidity of the vibration plate <NUM> can be detected with high accuracy. Therefore, an influence of humidity on the vibration plate <NUM> can be appropriately managed.

With the liquid ejecting head 510c of the present embodiment, the vibration plate <NUM> includes a first layer, a second layer laminated on the first layer, and a boundary surface 50IN between the first layer and the second layer. The boundary surface 50IN is disposed between the first detection electrode <NUM> and the second detection electrode <NUM>. Therefore, even when the vibration plate <NUM> is formed by laminating two layers, by acquiring the resistance of the boundary surface 50IN of the vibration plate <NUM>, an influence of humidity on the vibration plate <NUM> can be appropriately managed.

<FIG> is a fourth explanatory diagram illustrating the humidity detection section 210c1 included in the liquid ejecting head of another embodiment. The third embodiment describes an example in which the first detection electrode 211c and the second detection electrode 212c are disposed in the recessed portions 50R1 and 50R2 formed in the vibration plate <NUM>. On the other hand, as illustrated in <FIG>, the first detection electrode 211c1 and the second detection electrode 212c1 may be disposed on the upper side of the vibration plate <NUM> without providing the recessed portions 50R1 and 50R2 in the vibration plate <NUM>. With such a configuration, the resistance of the surface of the insulator film <NUM> of the vibration plate <NUM> can be detected. With the liquid ejecting head of the embodiment, information on humidity of the insulator film <NUM> can be detected with high accuracy by a simple method of detecting resistance of the upper surface of the vibration plate <NUM>, and thus an influence of humidity on the insulator film <NUM> can be appropriately managed. The first detection electrode 211c1 and the second detection electrode 212c1 may be disposed on the lower side of the vibration plate <NUM>.

(D1) <FIG> is a first explanatory diagram illustrating another disposition example of the humidity detection section. Each of the embodiments describes an example in which, in plan view, the humidity detection sections are disposed at total four positions including positions adjacent to both sides of the first pressure chamber row L1 along the first arrangement direction and positions adjacent to both sides of the second pressure chamber row L2 along the second arrangement direction. On the other hand, as illustrated in <FIG>, for example, the humidity detection sections <NUM> may be disposed at positions adjacent to both sides of the wiring substrate <NUM> along the Y-axis direction which is the first arrangement direction. Alternatively, the humidity detection sections <NUM> may be disposed only at a position adjacent to any one side of the wiring substrate <NUM> along the Y-axis direction. With the liquid ejecting head <NUM> configured as described above, by disposing the humidity detection section <NUM> at a position separated from the piezoelectric element <NUM>, an influence of noise of the drive signal of the piezoelectric element <NUM> on the humidity detection section <NUM> can be reduced. Further, for example, when one holding portion <NUM> common to a plurality of pressure chamber rows such as the first pressure chamber row L1 and the second pressure chamber row L2 is provided, the number of the humidity detection sections <NUM> can be reduced, and thus information on humidity can be efficiently acquired.

(D2) <FIG> is a second explanatory diagram illustrating another disposition example of the humidity detection section. As illustrated in <FIG>, the humidity detection section 210d may be provided on the protective film <NUM> that is disposed to cover the end portion 80b and the surface of the piezoelectric body <NUM> at the drive electrode end portion position overlapping the end portion 80b of the second drive electrode <NUM>. In this case, the protective film <NUM> functions as the interlayer 215d. As illustrated in <FIG>, the first humidity detection wiring <NUM> and the second humidity detection wiring <NUM> are disposed at positions that face each other with the plurality of first drive wirings <NUM> interposed therebetween and are on the inner side of the liquid ejecting head 510d with respect to the second drive wiring <NUM>.

<FIG> is an enlarged explanatory diagram illustrating a partial range AR of <FIG>. As illustrated in <FIG>, the first detection electrode 211d and the second detection electrode 212d are disposed on the upper surface of the protective film <NUM> so as to face each other. With the liquid ejecting head 510d configured as described above, the same effect as that of the first embodiment can be obtained, and by using the existing protective film <NUM> as the interlayer 215d, an increase in the number of components because of installation of the humidity detection section 210d can be suppressed. Although detailed illustration of the shapes of the first detection electrode 211d and the second detection electrode 212d is omitted, any shape such as a linear shape, a flat plate shape, and a comb shape described above can be used.

The present disclosure is not limited to the above-described embodiments, and can be realized in various configurations without departing from the scope of the present invention as defined by the claims.

With the liquid ejecting head according to the aspect, by disposing the humidity detection section at a position separated from the piezoelectric element, an influence of noise of the drive signal of the piezoelectric element on the humidity detection section can be reduced.

The present disclosure can also be realized in various aspects other than the liquid ejecting apparatus and the liquid ejecting head. For example, the present disclosure can be realized in aspects of a method for manufacturing a liquid ejecting head, a method for manufacturing a liquid ejecting apparatus, or the like.

The present disclosure is not limited to an ink jet method, and can be applied to any liquid ejecting apparatuses that ejects a liquid other than ink and a liquid ejecting head that is used in the liquid ejecting apparatuses. For example, the present disclosure can be applied to the following various liquid ejecting apparatuses and liquid ejecting heads thereof.

Claim 1:
A liquid ejecting head (<NUM>) comprising:
a piezoelectric element (<NUM>) that includes a first drive electrode (<NUM>), a second drive electrode (<NUM>), and a piezoelectric body (<NUM>), the piezoelectric body being provided between the first drive electrode and the second drive electrode in a lamination direction in which the first drive electrode, the second drive electrode, and the piezoelectric body are laminated;
a vibration plate (<NUM>) that is provided on one side of the lamination direction with respect to the piezoelectric element and is deformed by driving of the piezoelectric element; and
a pressure chamber substrate (<NUM>) that is provided on the one side of the lamination direction with respect to the vibration plate and is provided with a plurality of pressure chambers, characterized by further comprising:
an interlayer (<NUM>) that is laminated on at least one of the piezoelectric body, the vibration plate, or the pressure chamber substrate and of which resistance changes according to humidity;
a first detection electrode (<NUM>) that is in contact with the interlayer; and
a second detection electrode (<NUM>) that is in contact with the interlayer and faces the first detection electrode.