JP2012099705A - Liquid injection head, liquid injection apparatus, piezoelectric device, and piezoelectric ceramic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid injection head equipped with a piezoelectric device with light environmental load, having excellent piezoelectric characteristics.SOLUTION: A liquid injection head 600 comprises: a pressure generation chamber 622 to communicate with a nozzle hole 612; a piezoelectric layer 20; and a piezoelectric device 100 having electrodes 10 and 30 which apply an electric voltage to the piezoelectric layer 20. The piezoelectric layer 20 is composed of a complex oxide of a perovskite-type structure. The complex oxide contains bismuth, sodium, and barium as A site elements and contains titanium as a B site element. A molar ratio of A site elements to B site elements (A site elements/B site elements) is 1.04 or higher and 1.08 or lower.

Description

  The present invention relates to a liquid ejecting head, a liquid ejecting apparatus, a piezoelectric element, and a piezoelectric ceramic.

  The liquid ejecting head is used in a liquid ejecting apparatus such as an ink jet printer. The liquid ejecting head is used for ejecting and ejecting small droplets of ink, whereby the ink jet printer can perform printing by attaching the ink to a medium such as paper.

  The liquid ejecting head generally includes a piezoelectric element that applies pressure to the liquid in order to eject the liquid from the nozzle. Examples of the piezoelectric element include a piezoelectric material exhibiting an electromechanical conversion function, for example, a structure in which a piezoelectric layer made of crystallized piezoelectric ceramic is sandwiched between two electrodes. Such a piezoelectric element can be deformed when a voltage is applied by an electrode, and can be operated by bending vibration, for example.

  The piezoelectric material used for such applications preferably has high piezoelectric properties such as electromechanical conversion efficiency, and the properties are superior to other materials. Therefore, lead zirconate titanate (PZT) Research and development of materials of the system has been carried out.

However, in recent years, there has been an increasing demand for further improving the piezoelectric characteristics of piezoelectric materials, and it has become necessary to use materials with a smaller environmental load. With PZT-based materials, it has become difficult to meet these requirements. For example, the development of perovskite-type oxide piezoelectric materials (piezoelectric ceramics) with reduced lead content has been advanced. As such a perovskite oxide, a piezoelectric layer made of a complex oxide represented by (Bi, Na, Ba) TiO ₃ has been proposed (see Patent Document 1).

  By the way, in general, a piezoelectric layer can be obtained by crystallizing a precursor layer that becomes a precursor of the piezoelectric layer by heat treatment. At this time, a pyroqua phase is generated and desired piezoelectric characteristics are obtained. It may not be obtained (see Patent Document 2).

JP 2007-266346 A JP 2009-57599 A

  One of the objects according to some aspects of the present invention is to provide a piezoelectric ceramic and a piezoelectric element having a small environmental load and good piezoelectric characteristics. Another object of some aspects of the present invention is to provide a liquid ejecting head and a liquid ejecting apparatus having the piezoelectric element.

A liquid ejecting head according to the present invention includes:
A pressure generating chamber communicating with the nozzle hole;
A piezoelectric element having a piezoelectric layer and an electrode for applying a voltage to the piezoelectric layer;
Including
The piezoelectric layer includes a complex oxide having a perovskite structure,
The composite oxide is
As elements of the A site, bismuth, sodium, and barium are included,
Titanium is included as an element of B site,
The molar ratio of the A site element to the B site element (A site element / B site element) is 1.04 to 1.08.

  According to the present invention, it is possible to provide a liquid ejecting head having a piezoelectric element that has a small environmental load and can suppress generation of a pyrochlore phase and has excellent piezoelectric characteristics.

In the liquid jet head according to the present invention,
The composite oxide may further contain manganese as an element of the B site.

  According to the present invention, the leakage current of the piezoelectric element can be reduced.

In the liquid jet head according to the present invention,
The ratio of the barium to the total amount of the bismuth, the sodium, and the barium may be 6 mol% or more and 14 mol% or less.

  According to the present invention, it is possible to provide a liquid ejecting head having a piezoelectric element having a small environmental load and good piezoelectric characteristics.

In the liquid jet head according to the present invention,
The molar ratio (bismuth / sodium) of the bismuth to the sodium in the element at the A site may be 0.85 or more and 1.17 or less.

  According to the present invention, it is possible to provide a liquid ejecting head having a piezoelectric element having a small environmental load and good piezoelectric characteristics.

A liquid ejecting apparatus according to the present invention includes:
The liquid ejecting head according to the invention is provided.

  According to the present invention, it is possible to provide a liquid ejecting apparatus that has a low environmental load and a high liquid discharge capability.

The piezoelectric element according to the present invention is
A piezoelectric layer;
An electrode for applying a voltage to the piezoelectric layer;
Including
The piezoelectric layer includes a complex oxide having a perovskite structure,
The composite oxide is
As elements of the A site, bismuth, sodium, and barium are included,
Titanium is included as an element of B site,
The molar ratio of the A site element to the B site element (A site element / B element) is 1.04 to 1.08.

  According to the present invention, it is possible to provide a piezoelectric element having a small environmental load and good piezoelectric characteristics.

The piezoelectric ceramic according to the present invention is
A piezoelectric ceramic containing a complex oxide having a perovskite structure,
The composite oxide is
As elements of the A site, bismuth, sodium, and barium are included,
Titanium is included as an element of B site,
The molar ratio of the A site element to the B site element (A site element / B element) is 1.04 to 1.08.

  According to the present invention, it is possible to provide a piezoelectric ceramic having a small environmental load and good piezoelectric characteristics.

FIG. 3 is a cross-sectional view schematically showing the piezoelectric element according to the embodiment. Sectional drawing which shows typically the manufacturing process of the piezoelectric element which concerns on this embodiment. Sectional drawing which shows typically the manufacturing process of the piezoelectric element which concerns on this embodiment. Sectional drawing which shows typically the manufacturing process of the piezoelectric element which concerns on this embodiment. XRD results of Examples, Comparative Examples, and Reference Examples. XRD results of Examples, Comparative Examples, and Reference Examples. XRD results of Examples, Comparative Examples, and Reference Examples. XRD results of Examples, Comparative Examples, and Reference Examples. FIG. 3 is a cross-sectional view schematically illustrating the liquid ejecting head according to the embodiment. FIG. 3 is an exploded perspective view schematically illustrating the liquid ejecting head according to the embodiment. FIG. 3 is a perspective view schematically illustrating the liquid ejecting apparatus according to the embodiment.

  Preferred embodiments of the present invention will be described below with reference to the drawings.

1. Piezoelectric Ceramics First, the piezoelectric ceramics according to the present embodiment will be described. The piezoelectric ceramic according to the present embodiment includes a complex oxide having a perovskite crystal structure. The composite oxide according to the present embodiment includes bismuth, sodium, and barium as elements of the A site having a perovskite structure, and includes titanium as an element of the B site. It can be said that the complex oxide according to the present embodiment is a solid solution of bismuth sodium titanate and barium titanate.

In the composite oxide according to the present embodiment, the molar ratio of the A site element (total amount of bismuth, sodium, and barium) to the B site element (titanium) (A site element / B site element) is 1 0.04 to 1.08. That is, the element at the A site is 4% to 8% in excess of the stoichiometric ratio of the perovskite structure represented by the general formula ABO ₃ . By setting it as such a ratio, the production | generation of a pyrochlore phase can be suppressed (details are mentioned later).

  The ratio of bismuth, sodium, and barium is not particularly limited as long as the composite oxide according to the present embodiment has a perovskite crystal structure, but the molar ratio of bismuth to the total amount of bismuth, sodium, and barium is 0.3. It is preferable that it is 0.6 or less. Further, the molar ratio of sodium to the total amount of bismuth, sodium, and barium is preferably 0.3 or more and 0.6 or less. The molar ratio of barium to the total amount of bismuth, sodium, and barium is preferably 0.03 or more and 0.15 or less. By setting such a ratio, the displacement amount of the piezoelectric ceramic can be further increased.

  More specifically, the ratio of barium to the total amount of bismuth, sodium, and barium is preferably 6 mol% or more and 14 mol% or less. The molar ratio of bismuth to sodium (bismuth / sodium) is preferably 0.85 or more and 1.17 or less. Thereby, piezoelectric characteristics, such as a displacement amount, can be improved.

  The composite oxide according to this embodiment may further contain manganese as an element of the B site. For example, the molar ratio of manganese to titanium is preferably about 0.01. Thereby, the insulation of piezoelectric ceramic can be enlarged and a leakage current can be reduced.

  Piezoelectric ceramics include K, Li, Mg, Ca, Sr, V, Nb, Ta, Cr, Mo, W, Co, Ni, Cu, Zn, Al, Si, La, Ce, Pr, Nd, Pm, Although it is known to improve the characteristics by adding various elements such as Sm and Eu, naturally, such an additive may be further included as long as the effects of the present invention can be obtained.

  According to the piezoelectric ceramic according to the present embodiment, the environmental load is small, generation of a pyrochlore phase can be suppressed, and excellent piezoelectric characteristics can be obtained (details will be described later).

2. Next, the piezoelectric element according to the present embodiment will be described with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing a piezoelectric element 100 according to the present embodiment.

  As shown in FIG. 1, the piezoelectric element 100 can include a first electrode 10, a piezoelectric layer 20, and a second electrode 30. For example, the piezoelectric element 100 is formed above the substrate 1.

  The substrate 1 is a flat plate made of, for example, a conductor, a semiconductor, or an insulator. The substrate 1 may be a single layer or a structure in which a plurality of layers are stacked. The internal structure of the substrate 1 is not limited as long as the upper surface is planar. For example, the substrate 1 may have a structure in which a space or the like is formed. The substrate 1 may include a diaphragm that is flexible and can be deformed (bent) by the operation of the piezoelectric layer 20. Examples of the material of the diaphragm include zirconium oxide, silicon oxide, or a laminate thereof.

  The first electrode 10 is formed on the substrate 1. The shape of the first electrode 10 is, for example, a layer shape or a thin film shape. The thickness of the first electrode 10 is, for example, not less than 50 nm and not more than 300 nm. The planar shape of the first electrode 10 is not particularly limited as long as the piezoelectric layer 20 can be disposed between the second electrodes 30 when the second electrodes 30 are disposed to face each other. For example, the planar shape is rectangular or circular. .

Examples of the material of the first electrode 10 include various metals such as nickel, iridium and platinum, conductive oxides thereof (for example, iridium oxide), strontium and ruthenium composite oxide (SrRuO _x : SRO), lanthanum, and the like. And nickel composite oxide (LaNiO _x : LNO). The first electrode 10 may have a single-layer structure made of the materials exemplified above, or may have a structure in which a plurality of materials are stacked.

  One of the functions of the first electrode 10 is to form a pair with the second electrode 30 to apply a voltage to the piezoelectric layer 20 (for example, a lower portion formed below the piezoelectric layer 20). Electrode).

  In addition, the board | substrate 1 does not have a diaphragm, but the 1st electrode 10 may have a function as a diaphragm. That is, the first electrode 10 has a function as one electrode for applying a voltage to the piezoelectric layer 20 and a function as a diaphragm that can be deformed by the operation of the piezoelectric layer 20. May be.

  Moreover, although not shown in figure, between the 1st electrode 10 and the board | substrate 1, the layer which provides both adhesiveness, and the layer which provides intensity | strength and electroconductivity may be formed, for example. Examples of such layers include various metals such as titanium, nickel, iridium, and platinum, and oxide layers thereof.

  The piezoelectric layer 20 is formed on the first electrode 10. The shape of the piezoelectric layer 20 is, for example, a layer shape or a thin film shape. The thickness of the piezoelectric layer 20 is, for example, not less than 300 nm and not more than 3000 nm. The piezoelectric layer 20 can have piezoelectricity and can be deformed by applying an electric field by the first electrode 10 and the second electrode 30 (electromechanical conversion).

  The piezoelectric layer 20 is made of the piezoelectric ceramic described in the above section “1. Piezoelectric ceramic”. Therefore, the piezoelectric element 100 has a small environmental load, can suppress generation of a pyrochlore phase, and can have good piezoelectric characteristics (details will be described later).

  The second electrode 30 is formed on the piezoelectric layer 20. The shape of the second electrode 30 is, for example, a layer shape or a thin film shape. The thickness of the second electrode 30 is, for example, not less than 50 nm and not more than 300 nm. The planar shape of the second electrode 30 is not particularly limited, and is, for example, a rectangle or a circle. As the second electrode 30, the materials listed above as the material of the first electrode 10 can be used.

  One of the functions of the second electrode 30 is to form a pair with the first electrode 10 to apply a voltage to the piezoelectric layer 20 (for example, an upper portion formed above the piezoelectric layer 20). Electrode).

  In the illustrated example, the second electrode 30 is formed on the upper surface of the piezoelectric layer 20, but may be further formed on the side surface of the piezoelectric layer 20 and the upper surface of the substrate 1.

  The piezoelectric element 100 as described above may be applied to, for example, a liquid ejecting head or a liquid ejecting apparatus (ink jet printer) using the liquid ejecting head as a piezoelectric actuator that pressurizes the liquid in the pressure generating chamber. The piezoelectric layer may be used for other purposes such as a piezoelectric sensor that detects deformation of the piezoelectric layer as an electrical signal.

3. Next, a method for manufacturing a piezoelectric element according to this embodiment will be described. 2-4 is sectional drawing which shows typically the manufacturing process of the piezoelectric element 100 which concerns on this embodiment.

  As shown in FIG. 2, the first electrode 10 is formed on the substrate 1. Here, the substrate 1 is formed, for example, by laminating a silicon oxide layer and a zircon oxide layer in this order on a silicon substrate. The silicon oxide layer is formed by, for example, a thermal oxidation method. The zircon oxide layer is formed by sputtering, for example.

  The first electrode 10 is formed by forming a first electrode layer (not shown) and then patterning the first electrode layer. The first electrode layer is formed, for example, by sputtering, vacuum deposition, or MOCVD (Metal Organic Chemical Vapor Deposition). The patterning is performed by, for example, a photolithography technique and an etching technique.

  Next, a piezoelectric layer made of the piezoelectric ceramic according to the present embodiment is formed on the first electrode. The piezoelectric layer can be formed by a sputtering method, a laser ablation method, or the like. In the following example, a case where the piezoelectric layer is formed by a film forming method typified by a sol-gel method or a MOD (Metal Organic Deposition) method is used. ,explain.

  As shown in FIG. 3, the precursor solution used as the raw material liquid of the piezoelectric layer 20 is apply | coated on the 1st electrode 10, and the precursor layer 22 is formed (application | coating process). The precursor solution is applied by, for example, a spin coat method.

  The precursor solution of the piezoelectric layer 20 includes a metal compound containing bismuth, a metal compound containing sodium, a metal compound containing barium, and a metal compound containing titanium. Furthermore, the precursor solution may contain a metal compound containing manganese. The precursor solution is obtained by mixing each metal compound at a desired molar ratio so that the piezoelectric layer 20 includes a composite oxide having a perovskite structure, and dissolving and dispersing the mixture using an organic solvent. be able to. Examples of the metal compound containing the metal include metal alkoxides, organic acid metal salts, and organic metal complexes.

  Examples of the metal compound containing bismuth include triethoxy bismuth, tri-i-propoxy bismuth, acetylacetonate bismuth, bismuth nitrate, bismuth acetate, bismuth citrate, bismuth oxalate, bismuth tartrate, and bismuth 2-ethylhexanoate. Is mentioned.

  Examples of the metal compound containing sodium include sodium 2-ethylhexanoate, sodium acetate, and sodium acetylacetonate.

  Examples of the metal compound containing barium include barium acetate, barium octylate, and barium tetraethoxide.

  Examples of the metal compound containing titanium include tetramethoxy titanium, tetraethoxy titanium, tetra-i-propoxy titanium, tetra-n-propoxy titanium, tetra-i-butoxy titanium, tetra-n-butoxy titanium, and tetra-t-butoxy titanium. Acetylacetonato titanium, titanium nitrate, titanium acetate, titanium oxalate, titanium tartrate, titanium citrate, and tetra (2-ethylhexyl) titanate.

  Examples of the metal compound containing manganese include di-i-propoxy manganese, manganese (III) acetylacetonate, manganese nitrate, manganese acetate, manganese citrate, manganese oxalate, manganese tartrate, and manganese 2-ethylhexanoate. Can be mentioned.

  Examples of the organic solvent for dissolving the above metal compound include octane, xylene, butanol, or a mixture thereof.

  Next, the precursor layer 22 is dried by heat treatment (drying process). The heat treatment temperature in the drying step is, for example, 100 ° C. or more and 200 ° C. or less, and the treatment time is, for example, 1 minute or more and 5 minutes or less. Thereby, the solvent of the precursor solution can be evaporated.

Next, the dried precursor layer 22 is degreased by heat treatment (degreasing step). The heat treatment temperature in the degreasing step is 300 ° C. or more and 350 ° C. or less, and the treatment time is, for example, 1 minute or more and 10 minutes or less. Thus, the organic components contained in the precursor layer 22, for _example, as _{NO 2, CO 2, H 2} O, can be removed. The heat treatment in the drying step and the degreasing step can be performed, for example, by setting the hot plate at the above temperature in an air atmosphere.

  In addition, the precursor layer 22 which has a desired film thickness can be obtained by repeating an application | coating process, a drying process, and a degreasing process in multiple times.

  As shown in FIG. 4, the degreased precursor layer 22 is crystallized by heat treatment (firing) to form a piezoelectric layer 20a having a complex oxide having a perovskite structure (crystallization step). The crystallization step is performed by heat treatment at 550 ° C. or higher and 750 ° C. or lower in an oxygen atmosphere by, for example, RTA (Rapid Thermal Annealing).

  As shown in FIG. 1, the second electrode 30 is formed on the piezoelectric layer 20. For example, after the second electrode layer (not shown) is formed, the second electrode layer and the piezoelectric layer 20a are patterned to form the second electrode 30 and the piezoelectric layer 20. The second electrode layer is formed by, for example, sputtering, vacuum deposition, or MOCVD. The patterning is performed by, for example, a photolithography technique and an etching technique. Note that the second electrode layer and the piezoelectric layer 20a may be patterned at once or may be patterned separately.

4). Examples Hereinafter, the present invention will be described more specifically with reference to Examples, Comparative Examples, and Reference Examples. In addition, this invention is not limited at all by the following examples.

4.1. Preparation of sample 4.1.1. Example 1
First, a silicon oxide layer was formed on the surface of a silicon substrate by a thermal oxidation method to obtain a substrate. Next, a titanium layer was formed on the substrate by sputtering, and a platinum layer (first electrode) oriented in (111) was formed on the titanium layer by sputtering.

  Next, a piezoelectric layer was formed on the first electrode by spin coating. The method is as follows.

  First, an n-butanol solution in which a metal compound containing bismuth, sodium, barium, titanium, and manganese was dissolved was mixed at a predetermined ratio to prepare a precursor solution. And this precursor solution was dripped on the 1st electrode, the board | substrate was rotated, and the precursor layer was formed (application | coating process). The substrate was rotated at 500 rpm for 10 seconds and then rotated at 2500 rpm for 30 seconds.

Next, the precursor layer was dried by heat treatment at 150 ° C. for 3 minutes using a hot plate (drying step). And the dried precursor layer was degreased by heat-processing for 5 minutes at 350 degreeC using the hotplate (degreasing process). After performing this coating process, drying process, and degreasing process 6 times, it was baked at 750 ° C. for 1 minute in an oxygen atmosphere by RTA (Rapid Thermal Annealing) (crystallization process). Thereby, a piezoelectric layer containing a complex oxide represented by the following general formula (1) was formed.
(Bi _0.465 , Na _0.465 , Ba _0.15 ) TiO ₃ (1)

  Note that manganese is added to the composite oxide, and the molar ratio of manganese to titanium is 0.01.

4.1.2. Examples 2-7
Examples 2 to 7 include the composite oxide represented by the general formula (1), and the piezoelectric layer so that the molar ratio of the total amount of bismuth, sodium, and barium to titanium is the value shown in Table 1. It was formed by the same method as in Example 1 except for forming. Table 1 shows the number of moles of bismuth (Bi), sodium (Na), barium (Ba), and the total amount of these (Bi + Na + Ba) when the number of moles of titanium (Ti) is 100. ing. Further, Table 1 shows the ratio of barium to the total amount of bismuth, sodium, and barium (Ba / (Bi + Na + Ba)) (mol%). Furthermore, Table 1 shows the molar ratio (Bi / Na) of bismuth to sodium.

4.1.3. Comparative Examples 1 to 4 and Reference Example 1
In Comparative Examples 1 to 4 and Reference Example 1, the same method as in Example 1 was used except that the piezoelectric layer was formed so that the molar ratio of bismuth, sodium, and barium to titanium had the values shown in Table 1. Formed.

4.2. X-ray diffraction (XRD) evaluation Examples 1 to 7, Comparative Examples 1 to 4, and Reference Example 1 were subjected to X-ray diffraction evaluation. The X-ray diffractometer was introduced into a model number D8 Discover manufactured by Bruker AXS, and measured at room temperature using Cu-Kα rays as an X-ray source.

  FIG. 5 shows the XRD results of Example 1 and Comparative Example 1. FIG. 6 shows the XRD results of Examples 2 and 3 and Comparative Example 2. FIG. 7 shows the XRD results of Examples 4 and 5 and Comparative Example 3. FIG. 8 shows the XRD results of Examples 6 and 7 and Comparative Example 4. 5 to 8 also show the XRD results of Reference Example 1.

  5 to 8, peaks near 2θ = 23 ° and 32 ° are peaks caused by the perovskite phase. The peaks near 2θ = 15 °, 30 °, and 35 ° are peaks caused by the pyrochlore phase. The peaks near 2θ = 28 °, 34 °, and 36 ° are peaks caused by the substrate. The peak near 2θ = 40 ° overlaps the peak due to the perovskite phase and the peak due to the substrate.

  As shown in FIGS. 5 to 8, Examples 1 to 7 have smaller peak intensities due to the pyroqua phase than Comparative Examples 1 to 4 and Reference Example 1. That is, it was found that the formation of the pyrochlore phase can be suppressed by setting the molar ratio of the A site (total amount of bismuth, sodium, and barium) to the B site (titanium) to be 1.04 or more and 1.08 or less.

  In Examples 1 to 7, the ratio of barium to the total amount of bismuth, sodium, and barium (Ba / (Bi + Na + Ba)) was 6 mol% or more and 14 mol% or less. The molar ratio of bismuth to sodium (Bi / Na) was 0.85 or more and 1.17 or less.

  Moreover, in Table 1, what was able to suppress the production | generation of a pyrochlore phase was represented by "(circle)", and what confirmed the peak resulting from a pyrochlore phase was represented by "x".

5. Liquid Ejecting Head Next, the liquid ejecting head according to the present embodiment will be described with reference to the drawings. FIG. 9 is a cross-sectional view schematically showing the main part of the liquid jet head 600. FIG. 10 is an exploded perspective view of the liquid ejecting head 600, which is shown upside down from a state in which it is normally used.

  The liquid ejecting head 600 includes the piezoelectric element according to the present invention. Below, the example using the piezoelectric element 100 is demonstrated as a piezoelectric element which concerns on this invention.

  As shown in FIGS. 9 and 10, the liquid ejecting head 600 includes, for example, a vibration plate 1 a, a nozzle plate 610, a flow path forming substrate 620, a piezoelectric element 100, and a housing 630. In FIG. 10, the piezoelectric element 100 is illustrated in a simplified manner.

  As shown in FIGS. 9 and 10, the nozzle plate 610 has nozzle holes 612. Ink is ejected from the nozzle holes 612. The nozzle plate 610 is provided with a plurality of nozzle holes 612, for example. In the example illustrated in FIG. 10, the plurality of nozzle holes 612 are formed in a line. Examples of the material of the nozzle plate 610 include silicon and stainless steel (SUS).

  The flow path forming substrate 620 is provided on the nozzle plate 610 (lower in the example of FIG. 10). Examples of the material of the flow path forming substrate 620 include silicon. As the flow path forming substrate 620 divides the space between the nozzle plate 610 and the vibration plate 1a, as shown in FIG. 10, a reservoir (liquid storage portion) 624, a supply port 626 communicating with the reservoir 624, A pressure generation chamber 622 communicating with the supply port 626 is provided. In this example, the reservoir 624, the supply port 626, and the pressure generation chamber 622 will be described separately, but these are all liquid flow paths (for example, manifolds), and The flow path may be designed in any way. Further, for example, the supply port 626 has a shape in which a part of the flow path is narrowed in the illustrated example, but can be arbitrarily formed according to the design, and is not necessarily an essential configuration.

  The reservoir 624 can temporarily store ink supplied from the outside (for example, an ink cartridge) through a through hole 628 provided in the vibration plate 1a. The ink in the reservoir 624 can be supplied to the pressure generation chamber 622 via the supply port 626. The volume of the pressure generation chamber 622 changes due to the deformation of the diaphragm 1a. The pressure generation chamber 622 communicates with the nozzle hole 612, and ink or the like is discharged from the nozzle hole 612 when the volume of the pressure generation chamber 622 changes.

  Note that the reservoir 624 and the supply port 626 may be provided on a member (not shown) different from the flow path forming substrate 620 as long as the reservoir 624 and the supply port 626 communicate with the pressure generation chamber 622.

  The piezoelectric element 100 is provided on the flow path forming substrate 620 (lower in the example of FIG. 10). The piezoelectric element 100 is electrically connected to a piezoelectric element driving circuit (not shown), and can operate (vibrate or deform) based on a signal from the piezoelectric element driving circuit. The diaphragm 1a can be deformed by the operation of the piezoelectric layer 20, and the internal pressure of the pressure generating chamber 622 can be appropriately changed.

  As shown in FIG. 10, the housing 630 can accommodate the nozzle plate 610, the flow path forming substrate 620, the vibration plate 1 a, and the piezoelectric element 100. Examples of the material of the housing 630 include resin and metal.

  According to the liquid ejecting head 600, it is possible to have the piezoelectric element 100 having a small environmental load and good piezoelectric characteristics. Therefore, the liquid ejecting head 600 has a low environmental load and can have a high discharge capability.

  In the above example, the liquid ejecting head 600 that uses the piezoelectric element 100 that sandwiches the piezoelectric layer 20 between the two electrodes 10 and 30 and changes the volume of the pressure generation chamber 622 by bending vibration has been described. However, the liquid jet head according to the present invention is not limited to the above-described form. For example, a piezoelectric element formed by alternately stacking piezoelectric layers and electrodes is fixed to a fixed substrate, and pressure is generated by longitudinal vibration. The form which changes the volume of a chamber may be sufficient. In addition, the liquid ejecting head according to the present invention may have a form using a so-called shear mode type piezoelectric element that changes the volume of the pressure generation chamber not by expansion or contraction deformation of the piezoelectric element but by shear deformation.

  In the above example, the case where the liquid ejecting head 600 is an ink jet recording head has been described. However, the liquid ejecting head of the present embodiment is, for example, an electrode material ejecting head used for electrode formation such as a color material ejecting head, an organic EL display, and an FED (surface emitting display) used for manufacturing a color filter such as a liquid crystal display. It can also be used as a bio-organic matter ejecting head used for biochip manufacturing.

6). Next, the liquid ejecting apparatus according to the present embodiment will be described with reference to the drawings. FIG. 11 is a perspective view schematically showing the liquid ejecting apparatus 700 according to the present embodiment.

  The liquid ejecting apparatus 700 includes the liquid ejecting head according to the invention. Hereinafter, an example in which the liquid ejecting head 600 is used as the liquid ejecting head according to the invention will be described.

  As illustrated in FIG. 11, the liquid ejecting apparatus 700 includes a head unit 730, a driving unit 710, and a control unit 760. The liquid ejecting apparatus 700 further includes an apparatus main body 720, a paper feeding unit 750, a tray 721 on which the recording paper P is installed, a discharge port 722 for discharging the recording paper P, and an apparatus main body 720. And an operation panel 770 disposed on the upper surface.

  The head unit 730 includes an ink jet recording head (hereinafter, also simply referred to as “head”) configured from the liquid ejecting head 600 described above. The head unit 730 further includes an ink cartridge 731 that supplies ink to the head, and a transport unit (carriage) 732 on which the head and the ink cartridge 731 are mounted.

  The drive unit 710 can reciprocate the head unit 730. The drive unit 710 includes a carriage motor 741 serving as a drive source for the head unit 730, and a reciprocating mechanism 742 that receives the rotation of the carriage motor 741 and reciprocates the head unit 730.

  The reciprocating mechanism 742 includes a carriage guide shaft 744 supported at both ends by a frame (not shown), and a timing belt 743 extending in parallel with the carriage guide shaft 744. The carriage guide shaft 744 supports the carriage 732 while allowing the carriage 732 to freely reciprocate. Further, the carriage 732 is fixed to a part of the timing belt 743. When the timing belt 743 is caused to travel by the operation of the carriage motor 741, it is guided to the carriage guide shaft 744 and the head unit 730 reciprocates. During this reciprocation, ink is appropriately discharged from the head, and printing on the recording paper P is performed.

  In the present embodiment, an example of a liquid ejecting apparatus that performs printing while both the liquid ejecting head 600 and the recording paper P move is shown, but the liquid ejecting apparatus of the present invention includes the liquid ejecting head 600 and the recording. Any mechanism may be used as long as the paper P is printed on the recording paper P by changing its position relative to each other. Further, in the present embodiment, an example is shown in which printing is performed on the recording paper P. However, the recording medium that can be printed by the liquid ejecting apparatus of the present invention is not limited to paper, and may be cloth, film, A wide range of media such as metal can be used, and the configuration can be changed as appropriate.

  The control unit 760 can control the head unit 730, the drive unit 710, and the paper feed unit 750.

  The paper feeding unit 750 can feed the recording paper P from the tray 721 to the head unit 730 side. The paper feed unit 750 includes a paper feed motor 751 serving as a drive source thereof, and a paper feed roller 752 that rotates by the operation of the paper feed motor 751. The paper feed roller 752 includes a driven roller 752a and a drive roller 752b that face each other up and down across the feeding path of the recording paper P. The drive roller 752b is connected to the paper feed motor 751. When the paper supply unit 750 is driven by the control unit 760, the recording paper P is sent so as to pass below the head unit 730. The head unit 730, the drive unit 710, the control unit 760, and the paper feed unit 750 are provided inside the apparatus main body 720.

  According to the liquid ejecting apparatus 700, it is possible to have the liquid ejecting head 600 that has a low environmental load and high liquid ejection capability. Therefore, the liquid ejecting apparatus 700 has a small environmental load and can have a high discharge capacity.

  Although the embodiments of the present invention have been described in detail as described above, those skilled in the art will readily understand that many modifications are possible without substantially departing from the novel matters and effects of the present invention. Accordingly, all such modifications are intended to be included in the scope of the present invention.

1 substrate, 1a diaphragm, 10 first electrode, 20 piezoelectric layer, 20a piezoelectric layer,
22 precursor layer, 30 second electrode, 100 piezoelectric element, 600 liquid jet head,
610 nozzle plate, 612 nozzle hole, 620 flow path forming substrate, 622 pressure generation chamber,
624 reservoir, 626 supply port, 628 through-hole, 630 housing,
700 liquid ejecting apparatus, 710 driving unit, 720 apparatus main body, 721 tray,
722 discharge port, 730 head unit, 731 ink cartridge,
732 carriage, 741 carriage motor, 742 reciprocating mechanism,
743 Timing belt, 744 Carriage guide shaft, 750 Paper feed unit,
751 paper feed motor, 752 paper feed roller, 752a driven roller,
752b Driving roller, 760 controller, 770 operation panel

Claims (7)

A pressure generating chamber communicating with the nozzle hole;
A piezoelectric element having a piezoelectric layer and an electrode for applying a voltage to the piezoelectric layer;
Including
The piezoelectric layer includes a complex oxide having a perovskite structure,
The composite oxide is
As elements of the A site, bismuth, sodium, and barium are included,
Titanium is included as an element of B site,
The liquid ejecting head, wherein a molar ratio of the A site element to the B site element (A site element / B site element) is 1.04 to 1.08. In claim 1,
The composite oxide further includes manganese as an element of the B site. In claim 1 or 2,
The liquid ejecting head, wherein a ratio of the barium to a total amount of the bismuth, the sodium, and the barium is 6 mol% or more and 14 mol% or less. In any one of Claims 1 thru | or 3,
The liquid ejecting head, wherein a molar ratio (bismuth / sodium) of the bismuth to the sodium in the element at the A site is 0.85 or more and 1.17 or less.   A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1. A piezoelectric layer;
An electrode for applying a voltage to the piezoelectric layer;
Including
The piezoelectric layer includes a complex oxide having a perovskite structure,
The composite oxide is
As elements of the A site, bismuth, sodium, and barium are included,
Titanium is included as an element of B site,
The piezoelectric element, wherein a molar ratio of the A site element to the B site element (A site element / B element) is 1.04 to 1.08. A piezoelectric ceramic containing a complex oxide having a perovskite structure,
The composite oxide is
As elements of the A site, bismuth, sodium, and barium are included,
Titanium is included as an element of B site,
Piezoelectric ceramics wherein the molar ratio of the A site element to the B site element (A site element / B element) is 1.04 to 1.08.

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