JPH1093153A - Electromechanical conversion element, its manufacturing method and ink jet head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable burning at low temperature and reducing cost by adding metallic oxide to the particulate monocrystal bodies of a ferroelectric material which has been previously grown to a prescribed particle diameter. SOLUTION: An electromechanical conversion element 1 is provided on a substrate 4, and electrodes 5 and 5 are arranged on both the upper and lower surfaces. Then, the displacements in contraction and expansion are generated by applying a voltage between the electrodes 5 and 5. The electromechanical conversion element 1 is burnt by adding metallic oxide 3 to the particulate monocrystal body 2 of a ferroelectric material which has been previously grown to the prescribed particle diameter and forming them to prescribed forms. Particulate monocrystal bodies 2 are formed into the prescribed particle diameter by press-forming raw materials of lead titanate zirconate, primarily sintering and grinding it, press-forming it, secondarily sintering and grinding it. The n-type metallic oxide semiconductors ZnO and TiO2 and the p-type metallic oxide semiconductors NiO and CoO, which can realize burning at the low temperature, are used as the metallic oxide 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electromechanical transducer, a method for manufacturing the same, and an ink jet head.

[0002]

2. Description of the Related Art Conventionally, an electric signal is converted into a mechanical displacement,
Alternatively, an electromechanical transducer that converts mechanical displacement into an electric signal is an actuator element of an inkjet head,
Sound generators such as motors, capacitors, memories, microphones and speakers, or various sensors such as acceleration sensors, pressure sensors, vibration sensors, angular velocity sensors, and other vibration bodies,
It is used for many applications such as oscillators. In this specification, mechanical displacement is used to include displacement, stress, vibration, and the like.

[0003] An ink jet head using such an electromechanical transducer includes, for example, a plurality of ejection ports (nozzles) for ejecting ink droplets, an ink liquid chamber to which the nozzles communicate, and one wall surface of the ink liquid chamber. An electromechanical transducer such as a piezoelectric element that deforms a portion is provided, and by driving the electromechanical transducer, the volume of the ink liquid chamber is changed to eject ink droplets from a nozzle (piezo actuator type). I have.

[0004] As an ink jet recording apparatus using this ink jet head, a serial recording is carried out in which the ink jet head is mounted on a carriage and the carriage is scanned in the main scanning direction and the image receiving material is conveyed in the sub scanning direction to perform required recording. There is a scanning type recording apparatus or a line type recording apparatus using a line type inkjet head having a plurality of nozzles arranged in a row in the main scanning direction and having a length corresponding to, for example, an A4 width. This ink jet recording apparatus is widely used as various recording apparatuses such as a printer, a facsimile, a copying machine, a plotter and the like because of easy colorization.

As a conventional electromechanical transducer, a thin ceramic substrate, an electrode provided on the ceramic substrate, and a piezoelectric / electrostrictive layer are disclosed in, for example, Japanese Patent Application Laid-Open No. 5-29675. A piezoelectric / electrostrictive operating portion, wherein the piezoelectric / electrostrictive operating portion is formed by a film forming method, and the ceramic substrate is selected from the group consisting of yttrium oxide, ytterbium oxide, cerium oxide, calcium oxide and magnesium oxide. There is known a material formed of a material containing zirconium oxide as a main component, in which a crystal phase is stabilized by containing one compound.

In order to manufacture such an electromechanical transducer, as shown in FIG. 12, raw materials such as ferroelectric powder are weighed, mixed and dried, and then subjected to primary firing at 850 ° C. to 950 ° C. After grinding and drying, adding and mixing a binder, and performing cold pressing to form a predetermined product shape, for example, a shape of a piezoelectric element for an ink jet head, the ferroelectric powder is converted into a single crystal. The secondary firing is performed at a high temperature (generally, 1100 ° C. to 1450 ° C.) necessary for growth to obtain an electromechanical transducer having a predetermined shape. Alternatively, as described in
As described in JP-A-29675, a film is formed on a zirconia oxide substrate by using a paste or a slurry mainly composed of ceramic particles of a piezoelectric / electrostrictive material, and the film is fired at 900 ° C. to 1400 ° C. Methods are also known.

[0007]

As described above, in the conventional electromechanical transducer, the primary fired powder is heated at 850 ° C. to 1 ° C.
Baked at 000 ° C., formed into a desired shape using a binder or the like, and then subjected to secondary calcination at a high temperature of about 1300 ° C. to 1450 ° C. to grow ferroelectric material crystals. The crystal size of the material is small and the firing temperature is extremely high, resulting in an increase in cost.

Further, since the conventional electromechanical transducer has a high firing temperature, for example, when the electromechanical transducer is integrally formed on a substrate to form an ink jet head, the substrate itself is also fired at a high temperature. Zirconia oxide or the like must be used, which can withstand the temperature, and the cost is increasing. Therefore, the cost of the ink jet recording apparatus using the ink jet head is increasing. Furthermore, when manufacturing a line type ink jet head, it is difficult to obtain an ink jet recording apparatus which is low in yield, low in cost, and capable of high speed recording.

The present invention has been made in view of the above points, and has as its object to reduce the cost of an electromechanical transducer and an ink jet head using the electromechanical transducer by enabling low-temperature firing. .

[0010]

According to an aspect of the present invention, there is provided an electromechanical transducer for converting an electric signal into a mechanical displacement or converting a mechanical displacement into an electric signal. The element was configured such that a metal oxide was added to a fine-particle single crystal of a ferroelectric material which had been grown to a predetermined particle size in advance, followed by firing.

According to a second aspect of the present invention, there is provided the electromechanical conversion element according to the first aspect, wherein the particle size of the single crystal particles is 0.5 to 20 μm.

According to a third aspect of the present invention, in the electromechanical transducer of the first or second aspect, the metal oxide is an N-type or P-type oxide semiconductor.

According to a fourth aspect of the present invention, in the electromechanical transducer of the first or second aspect, the metal oxide is made of a dielectric material.

According to a fifth aspect of the present invention, in the electromechanical transducer according to any one of the first to fourth aspects, the ferroelectric material is a PbZrO ₃ .PbTiO ₃ based material.

According to a sixth aspect of the present invention, in the electromechanical transducer according to any one of the first to fourth aspects, the ferroelectric material is an antiferroelectric material.

According to a seventh aspect of the present invention, in the electromechanical transducer according to the sixth aspect, the antiferroelectric material is a PbLaZrSnTiO ₃ -based material or a PbNbZrSnTiO ₃ -based material.

An electromechanical transducer according to an eighth aspect of the present invention is the electromechanical transducer according to any one of the first to seventh aspects, wherein the surface of the fine-particle single crystal of the ferroelectric material is smooth.

According to a ninth aspect of the present invention, in the electromechanical conversion element according to any one of the first to eighth aspects, the fine particle single crystal of the ferroelectric material is subjected to a surface modification treatment. And

According to a tenth aspect of the present invention, there is provided a method of manufacturing an electromechanical transducer for converting an electric signal into a mechanical displacement or converting a mechanical displacement into an electric signal. After adding and mixing a metal oxide to the ferroelectric material fine-crystal single crystal grown in the above, the mixture was formed into a predetermined shape and fired at a temperature not exceeding 900 ° C.

According to a eleventh aspect of the present invention, in the method of the tenth aspect, the fine particle single crystal has a particle size of 0.5 to 20 μm.
m.

According to a twelfth aspect of the present invention, there is provided a method of manufacturing an electromechanical transducer according to the tenth or eleventh aspect, wherein an N-type or P-type oxide semiconductor is used as the metal oxide. did.

According to a thirteenth aspect of the invention, there is provided a method of manufacturing an electromechanical transducer according to the tenth or eleventh aspect, wherein a dielectric material is used as the metal oxide.

According to a fourteenth aspect of the present invention, there is provided the electromechanical transducer according to any one of the tenth to thirteenth aspects, wherein the ferroelectric material is PbZrO.
_It was configured to be a ₃ · PbTiO ₃ -based material.

According to a fifteenth aspect of the present invention, in the method of manufacturing an electromechanical transducer according to any one of the tenth to thirteenth aspects, the ferroelectric material is an antiferroelectric material. did.

A method of manufacturing an electromechanical transducer according to claim 16 is the method of manufacturing an electromechanical transducer of claim 15, wherein the antiferroelectric material is a PbLaZrSnTiO ₃ or PbNbZrSnTiO ₃ material. did.

According to a seventeenth aspect of the present invention, in the method for manufacturing an electromechanical conversion element according to any one of the tenth to sixteenth aspects, the ferroelectric material is formed by primary firing at a high temperature. After wet grinding and surface modification,
Secondary baking was performed at a high temperature, and this was pulverized to produce a fine-particle single crystal of a ferroelectric material which had been grown to a desired particle size in advance.

An ink-jet head according to claim 18 is an electro-mechanical transducer according to any one of claims 1 to 9, an ink liquid chamber whose internal volume is changed by displacement of the electro-mechanical transducer, and And a discharge port for discharging ink droplets in communication with each other.

According to a nineteenth aspect of the present invention, there is provided an ink-jet head comprising an electromechanical transducer manufactured by the method for manufacturing an electromechanical transducer according to any one of the tenth to seventeenth aspects, wherein the inner volume is changed by displacement of the electromechanical transducer. An ink liquid chamber and a discharge port for discharging ink droplets in communication with the ink liquid chamber are provided.

According to a nineteenth aspect of the present invention, in the inkjet head of the eighteenth or nineteenth aspect, a plurality of nozzles are arranged in a line in the main scanning direction.

[0030]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic sectional view of an electromechanical transducer to which the present invention is applied, and FIG. 2 is a schematic sectional view of a state where the electromechanical transducer is provided on a substrate.

The electromechanical transducer 1 is obtained by adding a metal oxide 3 to a fine crystal single crystal 2 of a ferroelectric material which has been grown to a predetermined particle size in advance, forming the metal oxide 3 into a predetermined shape, and firing it. It is. The electromechanical transducer 1 is disposed on a substrate 4 as shown in FIG. 2 and electrodes 5 and 5 are provided on both upper and lower surfaces, and by applying a voltage between the electrodes 5 and 5, displacement of contraction and extension is achieved. Can occur.

Here, since the electromechanical transducer 1 has the fine particle single crystal 2 of the ferroelectric material grown in advance to a desired particle size, the temperature does not exceed 900 ° C. (hereinafter referred to as “low temperature”). ). If the effect of the present invention due to the possibility of low-temperature firing can be obtained in a smaller range, a temperature exceeding the low temperature, that is, 900 ° C.
Baking at a temperature exceeding, for example, about 1300 ° C. as in the related art.

The particle size of the ferroelectric fine-particle single crystal 2 is preferably 0.5 to obtain a required displacement amount, for example, when used as an actuator element of an ink jet head.
μm to 20 μm are preferred.

PbZrO ₃ .PbTi is used as the ferroelectric material used as the fine-particle single crystal 2 of the ferroelectric material.
O ₃ (lead zirconate titanate) (PZT), lead magnesium niobate (PMN), lead nickel niobate (P
NN), lead manganese niobate, lead antimony stannate,
Materials such as zinc zinc niobate and lead titanate can be given. In this case, an antiferroelectric material can be used as the ferroelectric material. As antiferroelectric materials,
PbLaZrSnTiO ₃ (PLZST) or PbNbZrSn
TiO ₃ (PNZST) -based materials can be mentioned.
These antiferroelectric materials are about two times less than ferroelectric materials.
Double displacement is obtained.

[0035] As the metal oxide 3, which can be low-temperature _{firing, ZnO, TiO 2, SnO 2} , Al 2 O 3, Ta 2 O 5 or the like n a
Type (reduction type) metal oxide semiconductor, NiO, CoO, Fe
It is preferable to use a p-type (oxidation type) metal oxide semiconductor such as O, Cr ₂ O ₃ , and Bi ₂ O ₃ . A ferroelectric element as an electromechanical conversion element can be obtained by adding these metal oxide semiconductors at, for example, 0.5 to 10% by weight and firing at 300 to 800 ° C. That is, an electric field is applied through the grain boundary (crystal barrier layer) of the single crystal by the added metal oxide, and the polarity of the single crystal can be matched.

That is, conventionally, the ferroelectric element material was changed to 12
Since firing is performed at a high temperature of 00 ° C. to 1400 ° C., the applied polarity can be matched by thinning the grain boundary to 100 nm to 300 nm. .5 μm-10
Even when a voltage is applied as thick as μm, polarity matching may not be performed due to the high resistance of the boundary. Therefore, by using a metal oxide semiconductor as the metal oxide, the voltage can be applied (charged) to the interface between the single crystal particles to easily perform polarity matching. However, in this case, if the resistance of the grain boundary is 10 ³ to 10 ⁶ Ωcm or less, the resistance component exceeds the capacitance component, and the applied voltage may be in a conductive state, so that polarity matching may not be performed. Since this depends on the amount of the metal oxide added and the firing temperature, it is necessary to find optimal conditions.

As the metal oxide, an oxide of a dielectric material can be used. Examples of oxides of this dielectric material include Pb ₅ Ge ₃ O ₁₁ , PbTiO ₃ , and PbZr.
O ₃ and Pb (Mg _1/3 Nb _2/3 ) O ₃ -PbTiO ₃ .Pb
Materials such as ZrO ₃ can be used. Furthermore, Pb ₅ G
e _3-X (X = Si _2.4 to _2.6 ) can be fired at low temperature.

Further, a fine-grain single crystal of ferroelectric material 2
It is preferable to use one having a smooth surface. In order to smooth the surface of the fine particle single crystal 2, a surface modification treatment is performed. For example, a single crystal of fine particles of 0.5 to 20 μm is refined by a wet method (ball mill, ZrO 2). Thereby, the same series of fine particles in the amorphous state are generated.
This is because alcoholic solvents and acetic acid and mineral acids (HCl, HN
This is because the addition of a small amount of O ₃ ) activates the surface of uncrystallized fine particles on the surface of the single crystal and the surface of the particles pulverized by a ball mill. By gelling and amorphizing the powder, it becomes possible to form these powders, screen-print them, and fire them at a low temperature.

Since the electromechanical transducer 1 can be fired at a low temperature, the substrate 4 does not need to be a substrate that can withstand high temperature firing such as zirconium oxide.
Glass, quartz plate, alumina, steatite and the like can also be used as the substrate. Also, as the material of the electrode 5, an inexpensive material such as Ag-Pd can be used.

As described above, the metal oxide is added to the fine single crystal of the ferroelectric material which has been grown to a predetermined particle size in advance, and the resultant is fired to obtain the electromechanical transducer.
A desired product can be obtained at a sintering temperature (low-temperature sintering) not exceeding 00 ° C., a substrate and an electrode material having low heat resistance can be used, and temperature control in a device making process is also facilitated, and element Not only will the cost be lower,
For example, it is possible to reduce the cost of an ink jet head using this element and an ink jet recording apparatus provided with this head, and it is also possible to easily manufacture a line type ink jet head at low cost.

Next, an example of a method for manufacturing an electromechanical transducer according to the present invention will be described with reference to FIG. First,
Raw materials such as ferroelectric materials are weighed, and the raw materials are mixed by a ball mill or a mortar and dried.
Go cold pressed at 2t / cm ^2, 1100 ℃ ~1
Primary firing is performed at 450 ° C. Then, the fired product is pulverized with a ball mill while adding EtOH, dried, cold-pressed at 0.5 to ² t / cm ² , and then dried.
The secondary firing is performed at 100 ° C to 1450 ° C. Further, by pulverizing the secondary fired product with a ball mill while adding EtOH, a fine crystal single crystal of a ferroelectric material having a diameter of 0.5 to 2 μm can be obtained.

Therefore, a metal oxide is added to this for 0.5 to 10 minutes.
After wt% addition, dry mixing (mortar mixing), press molding, slurry screen printing, green sheeting, etc., and shaping, the temperature is adjusted to a temperature not exceeding 900 ° C, preferably 300 ° C to 800 ° C. By sintering at a low temperature, a product having a desired shape is obtained.

Here, the crystal growth of the ferroelectric material is 110
Occurs at elevated temperatures between 0 ° C. and 1450 ° C., particle enlargement occurs in dense powder agglomerates. Even if the powder is fired in a crucible or the like with the powder as before, only a fine particle single crystal having a particle size of about 0.1 to 1 μm can be obtained. However, by using the method described in FIG. Since a single crystal particle of about 5 to 20 μm can be obtained, an electromechanical transducer incorporating a single crystal ferroelectric with a large particle diameter can be obtained by firing at a low temperature by adding a metal oxide to the metal oxide. A large element can be obtained.

In the metal oxide mixing step, N-type or P-type
By adding 0.5 to 10 wt% of a type metal oxide semiconductor and performing low-temperature baking, the ferroelectric material has been increased in single crystal by high-temperature baking, so that the conductivity and the capacity component are matched. Thus, an electromechanical transducer is obtained. Since the conversion effect (piezoelectric effect) depends on the performance of the polycrystalline grained single crystal, an electromechanical conversion element that becomes a ferroelectric element even at low temperature firing can be obtained.

The model of the single crystal particles and the grain boundary will be described with reference to FIGS. The grain boundary (grain boundary barrier layer) 6 is a combination of the resistance R0 and the capacitance C0. It is necessary that the component of the resistance R0 be 10 ⁶ Ωcm or more. In addition, the resistance R inside the single crystal particle 2
Is about 10 to 10 ³ Ωcm, and the polarity is aligned at a threshold voltage or higher.

As the metal oxide, a different ferroelectric material such as Pb ₅ Ge ₃ O ₁₁ , PbTiO ₃ , PbZrO ₃ , and Pb (Mg _1/3 Nb _2/3 ) O ₃ -PbTiO ₃ .PbZrO ₃ By adding 0.5 to 10 wt% of such fine powder, a bandage layer can be formed even by firing at a temperature of 300 ° C. to 800 ° C. Some of these materials are easily vitrified and microcrystals are formed inside, so that a dense bandary layer can be formed. As a result, a synergistic effect with the piezoelectric effect of the single crystal body is obtained.

Next, another example of the method for manufacturing an electromechanical transducer according to the present invention will be described with reference to FIG. The single-crystal particles having a crystal growth of about 0.5 to 20 μm by the above-described secondary firing are partially pulverized by a ball mill. At this time, 20 to 30% of HCOH or CH ₃ COH is added to EtOH, or 20 to 30% of a mineral acid (HCl or HNO ₃ ) is added in a 1N (normal) solution. Thereby, the structure in which the crushed particles and the amorphous component of the single crystal particles are activated and a hydroxyl group is provided can be obtained. After drying and pulverizing again, cold press molding, green sheeting,
An electromechanical conversion element can be obtained by forming a desired element shape using a method such as screen printing and baking the element at a low temperature of about 300 ° C. to 900 ° C.

Next, an example of an ink jet head using the electromechanical transducer according to the present invention will be described with reference to FIGS. 7 is an external perspective view of the ink jet head, FIG. 8 is an enlarged sectional view of a main part of FIG. 7, and FIG. 9 is a perspective view of a nozzle plate.

The ink jet head has a liquid chamber plate 11 forming one or more common ink flow paths and a plurality of ink liquid chambers, ie, a pressurized liquid chamber, and discharge ports (nozzles and orifices) communicating with the pressurized liquid chamber. Plate 1 that forms an ink supply path that communicates a common ink flow path with a pressurized liquid chamber
2 and a plurality of piezoelectric elements 13 comprising the electromechanical transducers according to the present invention, which are actuator elements which are bonded or integrally fired with the liquid chamber plate 11 corresponding to each pressurized liquid chamber of the liquid chamber plate 11. I have.

The liquid chamber plate 11, as shown in FIG.
A plurality of recesses 11 a forming a plurality of pressurized liquid chambers 15, and a common ink flow path separated by the plurality of pressurized liquid chambers 15 and the partition 16 to supply ink to each pressurized liquid chamber 15. 1
7 are formed. Pressurized liquid chamber 15
The upper partition wall varies depending on the material.
The piezoelectric element 13 is bonded or integrally fired on the outer surface of the diaphragm 18 as a deformable diaphragm 18 having a thickness of 0 μm. An ink supply hole 19 through which ink from the outside flows into the common ink passage 17.
Is formed.

Here, as the material of the liquid chamber plate 11, if the piezoelectric element 13 is integrally fired as described above, low-temperature firing is possible. Therefore, an Si substrate, alumina, steatite, or the like may be used. it can. In the case of adhesion, a resin or the like can also be used, for example, an engineering plastic resin such as polyphenylene sulfide, polyether sulfone, or polyimide;
Alternatively, it is preferable to use a resin in which a particle material such as titanium, alumina, or a glass filler is mixed into these resins to reduce the coefficient of thermal expansion. Other ceramic materials include titania-based ceramics, silicon nitride, aluminum nitride,
Materials such as zirconia can also be used.

In this case, since the sintering temperature of the piezoelectric element 13 does not exceed 900 ° C. as described above, it is possible to form the liquid chamber plate 11 on an Si substrate or the like, and then to place the piezoelectric element 13 on the diaphragm 18. Can be integrally fired.

As shown in FIG. 7, on the outer surface of the liquid chamber plate 11, a common electrode pattern 22 connected to one electrode 21 of all the piezoelectric elements 13 in each row is formed, and the other of the piezoelectric elements 13 is formed. And the individual electrode patterns 24 individually connected to the electrodes 23. Here, the individual electrode pattern 24 and the other electrode 23 of the piezoelectric element 13 are connected by wire bonding, conductive bonding, FPC, or the like. GND is connected to the common electrode pattern 22 connected to the piezoelectric element 13 or a voltage of several tens of volts is applied, and several tens of volts are selectively applied to the individual electrode pattern 24.
Is applied. Further, an ink supply pipe 25 for supplying ink from the outside through the ink supply hole 19 is attached to the common ink flow path 17 of the liquid chamber plate 11.

As shown in FIGS. 8 and 9, a discharge port 27 facing the pressurized liquid chamber 15 and an introduction port 27a of the discharge port 27 are formed in the nozzle plate 12, and the partition wall of the liquid chamber plate 11 is formed. An ink supply path 18 for supplying ink from the common ink flow path 17 to the pressurized liquid chamber 15 is formed in correspondence with the ink supply path 16.

In this ink jet head, by applying a pulse-like voltage to the piezoelectric element 13, the thickness direction is expanded by the unimorph structure with the diaphragm portion 18 and the surface direction is contracted, so that the pressurized liquid chamber of the diaphragm portion 18 is contracted. 1
Deformation in five directions occurs, and the ink in the pressurized liquid chamber 15 is pressurized in a pulsed manner to eject ink droplets from the ejection openings 27.

Next, an example of a line type ink jet recording apparatus provided with a line type ink jet head using the electromechanical transducer according to the present invention will be described with reference to FIGS.
This will be described with reference to FIG. FIG. 10 is a schematic perspective view of a main part of an ink jet recording apparatus, and FIG. 11 is a schematic plan view of an ink jet head.

In this ink jet recording apparatus, an ink jet head 31 having a large number of discharge ports (nozzles) is minutely moved in the left-right (horizontal) direction by a step motor 32, and is recorded in a direction orthogonal to the main scanning direction by a transport roller 33. This is a line type recording apparatus that records a desired image on the recording paper 34 by discharging ink droplets 35 from the ejection ports of the inkjet head 31 while transporting the recording paper 34 as a medium (image receiving material).

As shown in FIG. 10, the ink jet head 31 forms an ink flow channel 42 which is an ink liquid chamber having a predetermined depth and a predetermined depth with a discharge port 41 at the tip end of the substrate 40 at a predetermined pitch. , Each ink channel groove 42, 42
A common flow channel groove 43 for temporarily storing ink is formed in communication with..., A vibration plate 44 is adhered on the substrate 40, and the ink flow channel grooves 42 on the vibration plate 44 are formed. , The piezoelectric elements 45 formed of the electromechanical transducer according to the present invention are provided.

In this ink jet recording apparatus,
For example, a nozzle pitch of 320 μm (interval between discharge ports 41)
Inkjet head 41 having a step motor 4
By performing stepping by 32 μm in the direction perpendicular to the recording paper transport direction in Step 2, an image can be recorded at a recording dot density of 800 dpi. Note that the inkjet head 41 can be minutely moved using a conventional piezoelectric element or a piezoelectric element formed by the electromechanical transducer according to the present invention instead of the step motor. That is, in this inkjet recording apparatus, recording is performed at a recording density higher than the nozzle pitch by slightly moving the line-type inkjet head.

Note that the electromechanical transducer according to the present invention comprises:
Not only can it be used as the actuator element of the ink jet head described in the above embodiments, but also other, a motor, a capacitor, a memory, a microphone, a sounding body such as a speaker, or an acceleration sensor, a pressure sensor,
It can be used for various applications such as various sensors such as a vibration sensor and an angular velocity sensor, as well as a vibrating body and an oscillating body. Further, the configurations of the above-described inkjet head and inkjet recording apparatus are not limited to those of the above-described embodiment.

[0061]

As described above, according to the electromechanical transducer of the first aspect, a metal oxide is added to a fine-particle single crystal of a ferroelectric material which has been grown to a predetermined particle size in advance, followed by firing. With this configuration, low-temperature baking can be performed, and the manufacturing cost of the device can be reduced.

According to the electromechanical transducer of the second aspect, in the electromechanical transducer of the first aspect, the grain size of the single crystal fine particles is 0.5 to 20 μm, so that a large displacement amount is obtained. can get.

According to the electromechanical transducer of the third aspect, in the electromechanical transducer of the first or second aspect, the metal oxide is an N-type or P-type oxide semiconductor. Polarity matching of the body can be easily performed.

According to the electromechanical transducer of the fourth aspect, in the electromechanical transducer of the first or second aspect, since the metal oxide is made of a dielectric material, a dense boundary layer is formed. be able to.

According to the electromechanical transducer of the fifth aspect, in the electromechanical transducer of any one of the first to fourth aspects, the ferroelectric material is a PbZrO ₃ .PbTiO ₃ material. Thus, an element having a large displacement can be obtained.

According to the electromechanical transducer of the sixth aspect, in the electromechanical transducer of any one of the first to fourth aspects, the ferroelectric material is made of an antiferroelectric material. Is obtained.

According to the electromechanical transducer of the seventh aspect, in the electromechanical transducer of the sixth aspect, the antiferroelectric material is a PbLaZrSnTiO ₃ -based or PbNbZrSnTiO ₃ -based material. Is obtained.

According to the electromechanical transducer of the eighth aspect, in the electromechanical transducer of any one of the first to seventh aspects, the surface of the fine single crystal of ferroelectric material is smooth. In addition, it is possible to manufacture an element free from damage by impurities and damage by interference with alkali ions.

According to the electromechanical transducer of the ninth aspect, in the electromechanical transducer of any one of the first to eighth aspects, the fine particle single crystal of the ferroelectric material is subjected to a surface modification treatment. With such a configuration, an element free from damage by impurities and interfering ion damage by alkali ions can be obtained, and the performance of the element is improved.

According to the method of manufacturing an electromechanical transducer of the tenth aspect, after a metal oxide is added to and mixed with a fine crystal single crystal of a ferroelectric material which has been grown in advance to a desired particle size, the mixture is subjected to a predetermined process. And fired at a temperature not exceeding 900 ° C., so that low-temperature firing is possible and temperature control is easy, and it is also possible to integrally fire with other members having low withstand temperature. , Cost is reduced.

According to the method of manufacturing an electromechanical transducer of the eleventh aspect, in the method of manufacturing an electromechanical transducer of the tenth aspect, the fine particle single crystal has a particle size of 0.5 to 20.
Since the structure using the μm is used, an element having a large displacement can be obtained.

According to a twelfth aspect of the present invention, there is provided the electromechanical transducer according to the tenth or eleventh aspect, wherein an N-type or P-type oxide semiconductor is used as the metal oxide. Therefore, the polarity of the single crystal can be easily matched.

According to the method of manufacturing an electromechanical transducer of claim 13, since a dielectric material is used as a metal oxide in the method of manufacturing an electromechanical transducer of claim 10 or 11, the method is more precise. A boundary layer can be configured.

According to a method of manufacturing an electromechanical transducer according to claim 14, in the method of manufacturing an electromechanical transducer according to any of claims 10 to 13, the ferroelectric material may be PbZr.
Since the structure is made of O ₃ .PbTiO ₃ material, an element having a large displacement can be obtained.

According to the method of manufacturing an electromechanical transducer of claim 15, in the method of manufacturing an electromechanical transducer of any one of claims 10 to 13, the ferroelectric material is an antiferroelectric material. Therefore, an element having a large displacement can be obtained.

According to a sixteenth aspect of the present invention, in the method of the fifteenth aspect, the antiferroelectric material is a PbLaZrSnTiO ₃ -based material or a PbNbZrSnTiO ₃ -based material. So,
An element having a large displacement can be obtained.

According to the method of manufacturing an electromechanical transducer of claim 17, in the method of manufacturing an electromechanical transducer of any one of claims 10 to 16, the ferroelectric material is formed by primary firing at a high temperature; After wet pulverization and surface modification, secondary baking is performed at a high temperature, and pulverization is performed to produce a fine crystal single crystal of a ferroelectric material previously grown to a desired particle size. As a result, it is possible to manufacture an element free from damage by impurities or damage by interference with alkali ions.

According to an ink jet head of the eighteenth aspect, the electromechanical transducer according to any one of the first to ninth aspects, an ink liquid chamber whose internal volume changes by displacement of the electromechanical transducer, Since the ink jet head is provided with a discharge port for discharging ink droplets in communication with the chamber, the cost of the ink jet head can be reduced.

According to a nineteenth aspect of the present invention, an electromechanical transducer manufactured by the method of manufacturing an electromechanical transducer according to any one of the tenth to seventeenth aspects, and the inner volume is reduced by displacement of the electromechanical transducer. With the configuration including the changing ink liquid chamber and the ejection port that communicates with the ink liquid chamber and ejects ink droplets, the cost of the ink jet head can be reduced.

According to a twentieth aspect of the present invention, in the ink jet head according to the eighteenth or nineteenth aspect, a plurality of nozzles are arranged in a line in the main scanning direction. The cost of the inkjet head can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an electromechanical transducer to which the present invention is applied.

FIG. 2 is a schematic cross-sectional view showing a state where the electromechanical transducer is arranged on a substrate.

FIG. 3 is a flowchart showing an example of a method for manufacturing an electromechanical transducer according to the present invention.

FIG. 4 is a schematic diagram illustrating a model of a single crystal particle and a grain boundary.

FIG. 5 is an explanatory diagram showing an equivalent circuit of FIG. 4;

FIG. 6 is a main part flowchart showing another example of the method for manufacturing an electromechanical transducer according to the present invention.

FIG. 7 is an external perspective view showing an example of an inkjet head using the electromechanical transducer according to the present invention.

FIG. 8 is an enlarged sectional view of a main part of FIG. 7;

FIG. 9 is a perspective view of the nozzle plate of FIG. 8;

FIG. 10 is a schematic perspective view of a main part of an ink jet recording apparatus having a line type ink jet head using an electromechanical transducer according to the present invention.

FIG. 11 is an explanatory diagram of the line type ink jet head.

FIG. 12 is a flowchart illustrating a conventional method for manufacturing an electromechanical transducer.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electromechanical conversion element, 2 ... Fine particle single crystal, 3 ... Metal oxide, 11 ... Liquid chamber plate, 13 ... Piezoelectric element, 12 ...
Nozzle plate, 27 ejection port, 31 line inkjet head.

Claims (20)

[Claims] An electromechanical transducer for converting an electrical signal into a mechanical displacement or converting a mechanical displacement into an electrical signal, wherein the electromechanical transducer is a ferroelectric material grown to a predetermined particle size in advance. An electromechanical conversion element characterized in that a metal oxide is added to a single-crystal fine particle of the above and fired. 2. The electromechanical transducer according to claim 1, wherein the particle size of the single-crystal fine particles is 0.5 to 20 μm. 3. The electromechanical transducer according to claim 1, wherein the metal oxide is an N-type or P-type oxide semiconductor. 4. The electromechanical transducer according to claim 1, wherein the metal oxide is made of a dielectric material. 5. The electromechanical transducer according to claim 1, wherein the ferroelectric material is PbZrO _3.
-An electromechanical transducer characterized by being a PbTiO ₃ -based material. 6. The electromechanical transducer according to claim 1, wherein the ferroelectric material is an antiferroelectric material. 7. The electromechanical transducer according to claim 6, wherein the antiferroelectric material is a PbLaZrSnTiO ₃ based material or a PbNbZrSnTiO ₃ based material. 8. The electromechanical transducer according to claim 1, wherein the surface of the single-crystal ferroelectric material is smooth. 9. The electromechanical transducer according to claim 1, wherein the fine-particle single crystal of the ferroelectric material has been subjected to a surface modification treatment. element. 10. A method of manufacturing an electromechanical transducer for converting an electric signal into a mechanical displacement or converting a mechanical displacement into an electric signal, wherein the fine particles of a ferroelectric material grown in advance to a desired particle size are used. A method for manufacturing an electromechanical transducer, comprising: adding a metal oxide to a crystal, mixing the mixture, forming the mixture into a predetermined shape, and firing at a temperature not exceeding 900 ° C. 11. The method for manufacturing an electromechanical transducer according to claim 10, wherein the fine single crystal having a particle size of 0.5 to 20 μm is used. 12. The method for producing an electromechanical transducer according to claim 10, wherein an N-type or P-type oxide semiconductor is used as the metal oxide. . 13. The method for manufacturing an electromechanical conversion device according to claim 10, wherein a dielectric material is used as the metal oxide. 14. The electromechanical transducer according to claim 10, wherein the ferroelectric material is a PbZrO ₃ .PbTiO ₃ material. Manufacturing method. 15. The method for manufacturing an electromechanical transducer according to claim 10, wherein the ferroelectric material is an antiferroelectric material. . 16. The method for manufacturing an electromechanical transducer according to claim 15, wherein the antiferroelectric material is PbLaZr.
A method for producing an electromechanical transducer, wherein the method is a SnTiO ₃ -based or PbNbZrSnTiO ₃ -based material. 17. The method for manufacturing an electromechanical transducer according to claim 10, wherein the ferroelectric material is formed by primary firing at a high temperature, and the ferroelectric material is wet-pulverized to perform surface modification. Thereafter, secondary firing is performed at a high temperature, and the resultant is pulverized to produce a fine-particle single crystal of a ferroelectric material which has been grown to a desired particle size in advance, thereby producing a method of manufacturing an electromechanical transducer. 18. An electromechanical transducer according to claim 1, an ink chamber whose internal volume is changed by displacement of said electromechanical transducer, and an ink droplet communicating with said ink chamber. And an ejection port for ejecting ink. 19. An electromechanical conversion element manufactured by the method for manufacturing an electromechanical conversion element according to claim 10, and an ink liquid chamber whose internal volume changes by displacement of the electromechanical conversion element. And an ejection port that communicates with the ink liquid chamber and ejects ink droplets. 20. The ink jet head according to claim 18, wherein the ink jet head is a line type head in which a plurality of nozzles are arranged in a line in a main scanning direction.