JP2010077011A - Method for producing ceramic powder, method for producing ceramic film, method for producing piezoelectric element, and method for manufacturing liquid droplet spraying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a production method of ceramic powder at lower temperature as compared with the traditional solid phase method; and a method for producing a ceramic film by using such production method. <P>SOLUTION: The production method of ceramic powder comprises a step of preparing a raw material solution containing a metal compound, and a step of forming powder by spray-drying the raw material solution, where the metal compound includes at least one of a hydrolyzable metal compound and a pyrolyzable organometallic compound. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a ceramic powder manufacturing method, a ceramic manufacturing method, a piezoelectric element manufacturing method, and a droplet jetting device manufacturing method.

  Composite metal oxides such as lead zirconate titanate (PZT) are used in various applications such as ferroelectric memories, piezoelectric elements, infrared sensors, and SAW devices, and their research and development are actively conducted. .

As a typical method for forming a composite metal oxide, there are a liquid phase method represented by a chemical solution method (CSD) such as a sol-gel method and a solid phase method.

  In the sol-gel method, a precursor solution obtained by polymerizing a compound such as a metal alkoxide by hydrolysis and polycondensation (also referred to as “hydrolysis / condensation”) is used. Such a sol-gel method has an advantage that the composition controllability of the resulting composite metal oxide is good by controlling the composition of the metal alkoxide solution.

  On the other hand, the solid-phase method is obtained by making a metal element oxide raw material of a composite metal oxide into powder, mixing these oxide raw materials in consideration of the stoichiometric composition, and then sintering this at a high temperature. It is done.

  One of the aspects according to the present invention is to provide a production method capable of obtaining ceramic powder at a lower temperature than a conventional solid phase method, and a production method of a ceramic film using the production method.

  One aspect of the present invention is to provide a method of manufacturing a piezoelectric element and a method of manufacturing a droplet ejecting apparatus using the method for manufacturing a ceramic powder according to the present invention.

A method for producing a ceramic powder according to one aspect of the present invention includes:
Preparing a solution containing a metal compound;
Forming a powder from the solution,
The metal compound includes at least one of a hydrolyzable metal compound and a thermally decomposable organometallic compound.

  According to such a method for producing a ceramic powder, a ceramic powder excellent in composition controllability can be obtained by a simple method at a lower temperature than the conventional solid phase method.

  The metal compound may include a first metal compound containing Pb, a second metal compound containing Zr, a third metal compound containing Ti, and a fourth metal compound containing Nb.

The first metal compound is lead acetate or lead octylate,
The second metal compound is Ti alkoxide, Ti acetate or Ti octylate,
The third metal compound may be niobium octylate or lead niobium octylate.

  The step of forming the powder can be performed using a spray drying method or a freeze drying method.

  Further, the solution can include silicon.

A method for producing a ceramic film according to one aspect of the present invention includes:
Forming a slurry from the ceramic powder produced by the ceramic powder production method;
Forming a film using the slurry;
Firing the film.

  A method for manufacturing a piezoelectric element according to one aspect of the present invention uses the above-described method for manufacturing a ceramic film.

  A method for manufacturing a droplet ejecting apparatus according to one aspect of the present invention uses the method for manufacturing a piezoelectric element described above.

A method for producing a ceramic film according to one aspect of the present invention includes:
Preparing a solution containing a metal compound;
Forming a first powder from the solution using a spray drying method or a freeze drying method;
Heating the first powder while stirring to form a second powder;
Pulverizing the second powder to form a third powder;
Forming the first ceramic body by forming and firing the third powder, or forming a slurry from the third powder, and forming and firing;
Crushing the first ceramic body to form a fourth powder;
Forming and firing the fourth powder, or forming a slurry from the fourth powder, forming a film, and firing.

  A method for manufacturing a piezoelectric element according to one aspect of the present invention uses the above-described method for manufacturing a ceramic film.

  A method for manufacturing a droplet ejecting apparatus according to one aspect of the present invention uses the method for manufacturing a piezoelectric element described above.

The flowchart figure which shows the manufacturing method of the ceramic powder concerning embodiment. The perspective view which shows typically the manufacturing method of the piezoelectric element concerning embodiment. The figure which shows typically the cross section of the piezoelectric element concerning embodiment. 1 is a perspective view schematically showing a droplet ejecting apparatus according to an embodiment. The figure which shows the result of the thermogravimetric analysis using the PZTN powder of an Example. The figure which shows the result of XRD using the PZTN powder of an Example. The figure which shows the composition of the raw material liquid of an Example, and PZTN powder. The figure which shows the result of XRD using the powder of the comparative example 2.

  Hereinafter, an example of an embodiment of the present invention will be described in detail.

1. Manufacturing method of ceramic powder The manufacturing method of the ceramic powder concerning this embodiment includes the process of preparing the raw material liquid containing a metal compound, and the process of spraying and drying the said raw material liquid and forming powder. . Hereinafter, a method for producing ceramic powder will be described with reference to FIG. FIG. 1 is a flowchart showing a method for producing a ceramic powder according to the present embodiment. In the following description, ceramics is also referred to as “complex metal oxide”.

1.1. Step of preparing raw material solution First, a raw material solution is prepared and prepared (step S1). The raw material liquid used in the present embodiment includes a metal compound. The metal compound is selected according to the ceramic to be obtained. The ceramic can have characteristics such as a piezoelectric material and a ferroelectric material. Examples of such ceramics include perovskite oxides, bismuth layered structure oxides, tungsten bronze structure oxides, and the like. Also, ceramics having characteristics such as piezoelectric and ferroelectric materials include lead zirconate titanate (PZT), barium titanate, potassium niobate (KN), BiFeO ₃ , {Bi (Na, K)} TiO _3. , {Bi (Na, K)} Ti, NbO ₃ , or an oxide in which a part of the metal constituting these oxides is substituted with another metal. Examples of the oxide in which a part of the metal constituting the oxide is substituted with another metal include those in which a part of the B site of lead zirconate titanate is substituted with niobium (hereinafter also referred to as “PZTN”). Can be mentioned.

The method for producing a ceramic powder according to the present embodiment is a ceramic in which good characteristics are difficult to obtain by a solid phase method, such as PZTN, that is, Pb (Zr, Ti) _1-x Nb _x (0.1 ≦ x ≦ 0). .3) is suitably applied to the ceramics shown.

  In the present embodiment, the metal compound can include a hydrolyzable metal compound such as a metal alkoxide, which is referred to as a so-called sol-gel raw material. The metal compound can further include a thermally decomposable organometallic compound such as an organometallic complex and an organic acid salt.

Hereinafter, as an example of ceramics suitably used for the piezoelectric element, it is represented by the formula AB _1-x C _x O ₃ (where, for example, 0.1 ≦ x ≦ 0.3), and the A element is at least from Pb. A mixed metal oxide raw material solution in which the B element is composed of Zr and Ti and the C element is composed of Nb or Ta will be described. The raw material liquid of such a composite metal oxide is described in detail in the specification of Japanese Patent Application No. 2005-344700. Further, the specification of the application describes that the ceramic film represented by the above formula obtained by applying heat treatment (drying, degreasing, firing) after applying the raw material solution has very good characteristics. Has been.

  The raw material liquid is (a) a thermally decomposable organometallic compound containing the A element, the B element or the C element, and (b) a hydrolyzable organometallic compound containing the A element, the B element or the C element. And (c) at least one selected from the partial hydrolyzate and / or polycondensate of (b), and at least one of polycarboxylic acid and polycarboxylic acid ester (preferably polycarboxylic acid ester) ) And an organic solvent.

  The concentration of the raw material liquid is preferably higher than that of a normal sol-gel raw material. The concentration of the metal compound in the raw material liquid is preferably from 0.5 mol / liter to 2 mol / liter in terms of molar concentration. The reason will be described later.

  The raw material liquid is prepared by mixing a metal compound each containing a constituent metal of a material to be a composite metal oxide, or a partial hydrolyzate and / or polycondensate thereof so that each metal has a desired molar ratio, These can be prepared by dissolving or dispersing them using an organic solvent such as alcohol. It is preferable to use a metal compound that is stable in a solution state.

  In the present embodiment, usable metal compounds are those that can be hydrolyzed or oxidized to form metal oxides derived from the metal organic compounds, and each metal alkoxide, organometallic complex, and Selected from organic acid salts.

  As the thermally decomposable metal compound containing each of the constituent metals of the composite metal oxide, for example, a metal compound such as a metal alkoxide, an organic acid salt, or a β-diketone complex can be used. A metal compound such as a metal alkoxide can be used as the hydrolyzable metal compound containing each of the constituent metals of the composite metal oxide. The following are mentioned as an example of a metal compound.

  Examples of the metal compound containing Zr and Ti which are B elements include these alkoxides (titanium tetra-N-butoxide, zirconium tetra-N-butoxide, etc.), acetates, octylates and the like.

  Examples of the metal compound containing Pb which is an A element include lead acetate and lead octylate.

  Examples of the metal compound containing Nb which is C element include niobium octylate and lead niobium octylate. Niobium octylate has a structure in which Nb is covalently bonded to two atoms and an octyl group is present in the other part. An example of the metal compound containing Ta which is C element is tantalum octylate.

  In the raw material liquid of the present embodiment, alcohol can be used as the organic solvent. When alcohol is used as the solvent, both the metal compound and the polycarboxylic acid or polycarboxylic acid ester can be dissolved well. Although it does not specifically limit as alcohol, In order to improve drying property, when using a spray-drying method, it is preferable to use what has a boiling point of 140 degrees C or less.

  Examples of such alcohols include monohydric alcohols such as butanol, methanol, ethanol, and propanol. Specific examples of the alcohol include the following.

Monohydric alcohols;
As propanol (propyl alcohol), 1-propanol (boiling point 97.4 ° C), 2-propanol (boiling point 82.7 ° C),
As butanol (butyl alcohol), 1-butanol (boiling point 117 ° C.), 2-butanol (boiling point 100 ° C.), 2-methyl-1-propanol (boiling point 108 ° C.), 2-methyl-2-propanol (melting point 25.4) ℃, boiling point 83 ℃),
As pentanol (amyl alcohol), 1-pentanol (boiling point 137 ° C.), 3-methyl-1-butanol (boiling point 131 ° C.), 2-methyl-1-butanol (boiling point 128 ° C.), 2,2 dimethyl-1 -Propanol (boiling point 113 ° C), 2-pentanol (boiling point 119 ° C), 3-methyl-2-butanol (boiling point 112.5 ° C), 3-pentanol (boiling point 117 ° C), 2-methyl-2-butanol (Boiling point 102 ° C.).

  In the raw material liquid, the polycarboxylic acid or the polycarboxylic acid ester can be divalent or higher. The following can be illustrated as polycarboxylic acid used for this invention. Examples of the trivalent carboxylic acid include Trans-aconitic acid, trimesic acid, and examples of the tetravalent carboxylic acid include pyromellitic acid and 1,2,3,4-cyclopentanetetracarboxylic acid. Polycarboxylic acid esters include divalent dimethyl succinate, diethyl succinate, dibutyl oxalate, dimethyl malonate, dimethyl adipate, dimethyl maleate, diethyl fumarate, trivalent tributyl citrate, 1,1 , 2-ethanetricarboxylic acid triethyl, tetravalent 1,1,2,2-ethanetetracarboxylic acid tetraethyl, 1,2,4-benzenetricarboxylic acid trimethyl and the like.

  In the raw material liquid, the divalent carboxylic acid ester can be preferably at least one selected from succinic acid esters, maleic acid esters and malonic acid esters. Specific examples of these esters include dimethyl succinate, dimethyl maleate, and dimethyl malonate.

  The polycarboxylic acid or polycarboxylic acid ester can have a higher boiling point than the organic solvent. Since the boiling point of the polycarboxylic acid or the polycarboxylic acid ester is higher than that of the organic solvent, the reaction of the raw material liquid can be performed more rapidly as described later.

  The molecular weight of the polycarboxylic acid ester may be 150 or less. If the molecular weight of the polycarboxylic acid ester is too large, the film tends to be damaged when the ester volatilizes during heat treatment, and a dense film may not be obtained.

  The polycarboxylic acid ester may be a liquid at room temperature. If the polycarboxylic acid ester is solid at room temperature, the liquid may gel.

  PZTN obtained by the raw material liquid of the present embodiment can preferably contain Nb in the range of 0.1 ≦ x ≦ 0.3. The composite metal oxide may contain 0.5 mol% or more, more preferably 0.5 mol% or more and 5 mol% or less of Si, or Si and Ge.

Nb is substantially the same size as Ti (the ionic radius is the same, and the atomic radius is the same), is twice as heavy, and it is difficult for atoms to escape from the lattice by collisions between atoms due to lattice vibration. The valence is +5, which is stable valence, even if Pb is released, it is possible to compensate for the valence of Pb loss by Nb ^5+. Further, even if Pb loss occurs during crystallization, it is easier to enter small Nb than large O loss.

In addition, since Nb also has a +4 valence, Ti ⁴⁺ can be sufficiently replaced. Furthermore, in fact, Nb has a very strong covalent bond, and Pb is considered to be difficult to escape (H. Miyazawa, E. Natori, S. Miyashita; Jpn. J. Appl. Phys. 39 (2000). 5679).

  According to the composite metal oxide obtained by the raw material liquid of the present embodiment, particularly PZTN, by containing Nb at a specific ratio, an adverse effect due to Pb deficiency is eliminated and excellent composition controllability is obtained. As a result, PZTN has extremely good hysteresis characteristics, leakage characteristics, reduction resistance, piezoelectricity, insulation, and the like compared to normal PZT.

  In the present embodiment, the crystallization energy of PZTN is reduced by including, in the composite metal oxide, Si or Si and Ge at a ratio of, for example, 0.5 mol% or more and 5 mol% or less. Can do. That is, when PZTN is used as the material of the composite metal oxide, the crystallization temperature of PZTN can be reduced by adding Si or i and Ge together with Nb. The inventors of the present application have confirmed by Raman vibration mode that Si forms a part of the crystal as A site ions after acting as a sintering agent.

  In the present embodiment, Ta can be used instead of Nb or together with Nb. Even when Ta is used, there is a tendency similar to that of Nb described above.

  The amount of polycarboxylic acid or polycarboxylic acid ester used depends on the composition of the composite metal oxide. For example, the total molar ion concentration of the metal and the molar ion concentration of the polycarboxylic acid (ester) for forming the composite metal oxide are preferably 1 ≧ (the molar ion concentration of the polycarboxylic acid (ester)) / (total of the metals in the raw material solution). Molar ion concentration).

  Here, the number of moles of polycarboxylic acid or polycarboxylic acid ester is a valence. That is, in the case of a divalent polycarboxylic acid or polycarboxylic acid ester, one molecule of the polycarboxylic acid or polycarboxylic acid ester corresponds to 0.1 mol of the polycarboxylic acid or polycarboxylic acid ester per 1 mol of the metal in the raw material solution. 5 moles is 1: 1.

1.2. Step of Forming Powder The method for producing ceramic powder according to the present embodiment includes a step of spraying the raw material liquid to form droplets and drying the droplets to form powder.

  In the present embodiment, first, the first powder is formed by spraying and drying the raw material liquid prepared in step S1 (step S2). The step of forming the first powder can be performed using a spray drying method or a freeze drying method. The spray drying method and the freeze drying method are not particularly limited as long as the raw material liquid can be made into droplets and dried, and known spray drying devices and freeze drying devices can be used. The particle size of the first powder obtained in this step varies depending on the raw material liquid, the type of apparatus, etc., but the average particle size is, for example, 1 μm or more and 3 μm or less.

  In the spray drying apparatus, it is preferable to use pressurized spraying by a pressure nozzle. Pressurized spraying can obtain particles having a smaller particle size compared to centrifugal spraying using a rotating disk and has good drying properties. When spray drying is used, drying is preferably performed at an atmospheric temperature (drying temperature) of 150 ° C. or lower.

Moreover, the raw material liquid contains the raw material for the ceramic to be obtained as described above. Such raw materials include sol-gel raw materials and MOD (Metal Organic Decomposition).
Method) It can contain liquid phase raw materials such as raw materials. The raw material liquid can have a higher concentration than the sol-gel raw material contained in the solution used in a general sol-gel method. Specifically, the raw material liquid can contain a metal compound of 02 mol / liter or more and 2 mol / liter or less. When the concentration of the metal compound is within this range, it is easy to remove the solvent, and there is an advantage that the generation efficiency of the raw material powder in the spraying / drying process is improved.

  Next, it is possible to have a step of heating the first powder obtained in step S2 while stirring (step S3). In this step, for example, the second powder from which the solvent and moisture of the raw material liquid remaining in the first powder are further removed by heating the first powder while stirring using a ball mill device, a pot mill device, or a mixer device. You can get a body. Although the temperature which heats 1st powder depends on the kind of solvent, the particle size of powder, etc., it can be 120 degreeC or more and 250 degrees C or less, for example. In addition, when the 1st powder obtained at the process of step S2 is fully dried, this stirring and heating process can be skipped.

  Next, the second powder obtained in step 3 is pulverized to obtain a third powder (step S4). In this step, the particle size of the second powder can be made smaller and the particle size can be made uniform. In this step, for example, a planetary ball mill device or a bead mill device can be used. The particle size of the third powder is not particularly limited, but may be suitable for the next temporary molding / firing. As the particle size of the third powder, for example, the average particle size can be 1 μm or more and 3 μm or less. Thus, by pulverizing the first or second powder, the particle size of the ceramic powder can be made uniform, and the ceramic can be molded and fired more satisfactorily. In addition, ceramics can also be formed using the 1st powder obtained by step S2 as it is.

  The ceramic powder according to this embodiment can be obtained through the above steps. According to such a method for producing a ceramic powder, a ceramic powder excellent in composition controllability can be obtained by a simple method at a lower temperature than the conventional solid phase method.

2. Manufacturing method of ceramics Ceramics can be obtained using the ceramic powder obtained by the method described in 1. above. The method for producing the ceramic is not particularly limited, and a method of forming and firing ceramic powder to form a so-called bulk ceramic, a method of forming and firing ceramic powder as a slurry, and the like can be used.

  Hereinafter, an example of a method for producing ceramics will be described with reference to FIGS. 1 and 2.

  That is, as shown in FIG. 1, the powder obtained in steps S2 to S4, preferably the third powder obtained in the fourth step S4, is formed into a shape such as a pellet (temporary molding), and A ceramic body is formed by firing (temporary firing) (step S5). Temporary forming and pre-firing vary depending on the type of ceramics, but may be performed at 600 ° C. or more and 800 ° C. or less for 1 hour or more and 2 hours or less while pressing at 1t / 10 mmφ or more and 2t / 10 mmφ or less, for example. it can. Next, the ceramic body obtained in step S5 is pulverized to form a ceramic powder (step S6). In this pulverization step, the average particle size of the ceramic powder can be reduced to, for example, submicron (02 μm or less, 005 μm or more) using a pulverizer such as a jet mill. The ceramic powder thus obtained has a small particle size and can be made uniform. Ceramics can be produced by molding and firing the ceramic powder.

  The method for producing the ceramic is not particularly limited, and a method for forming a so-called bulk ceramic by forming and firing ceramic powder, or forming a film ceramic by forming a film from ceramic powder as a slurry, followed by firing. A method or the like can be used.

3. Method for Manufacturing Piezoelectric Element A method for manufacturing a piezoelectric element using slurry will be described below.

in this way,
(1) a step of temporarily forming the ceramic powder obtained by the manufacturing method described above, and pre-firing to form a ceramic body;
(2) crushing the ceramic body to form a ceramic powder;
(3) forming a slurry containing ceramic powder;
(4) applying a slurry on a substrate (carrier tape) and drying to form a film (hereinafter also referred to as “green sheet”);
(5) forming an electrode film on the green sheet;
(6) forming a laminate in which a plurality of green sheets on which electrode films are formed are laminated;
(7) compressing and firing the laminate to form a ceramic laminate.

  Hereinafter, each step will be described in detail.

  Since steps (1) and (2) have already been described, the details are omitted (steps S5 and S6 in FIG. 1). Examples of ceramics suitable for the piezoelectric element include PZT, PZTN, barium titanate, potassium niobate, BiFeO3, and {Bi (Na, K)} TiO3 having excellent piezoelectric characteristics.

  In step (3), the slurry is prepared as follows. That is, the ceramic powder obtained through steps (1) and (2), an organic solvent, a binder, a plasticizer, a dispersant, and the like are mixed to obtain a slurry.

  The organic solvent is necessary to uniformly disperse the acrylic resin and the plasticizer in the slurry state of the ceramic mixture, improve the viscosity stability of the slurry, and apply thinly to the carrier tape. As such a solvent, a boiling point is 150 ° C. or less, and a ketone, alcohol, or hydrocarbon is preferable because it needs to be quickly removed in a drying process from a slurry state to a green sheet. Examples of ketones include acetone, methyl ethyl ketone, and methyl isobutyl ketone. Examples of alcohols include methanol, ethanol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, and ter-butyl alcohol. Examples of hydrocarbons include toluene and xylene.

  Although it does not specifically limit as a binder, For example, polyvinyl butyral, polyvinyl alcohol, etc. can be mentioned.

  The plasticizer has a function of stably mixing the ceramic mixture in a slurry state and stably reducing the slurry viscosity. By having these functions, it becomes easy to form a green sheet. In addition, a so-called waisted green sheet having a large elastic modulus and high strength can be formed. The plasticizer is not particularly limited, and examples thereof include alkyl esters composed of isophthalic acid, terephthalic acid, trimellitic acid, and alcohol having 4 to 18 carbon atoms, preferably n-butyl, isobutyl, n-hexyl, cyclohexyl. , N-octyl, 2-ethylhexyl, isononyl, dodecyl, isodecyl, oleyl alcohol, aminoester, and diester or triester.

  It is preferable to add a small amount of a dispersant as required. The dispersant has a function of improving the uniform dispersibility of the slurry. Such a dispersant is not particularly limited, and examples thereof include glycerin esters such as dioctyl and glycerin monooleate, animal and vegetable oils and fats such as soybean oil, palm oil, and fish oil, and synthetic surfactants.

  In steps (4), (5), and (6), a so-called green sheet is formed using the slurry obtained in step (3). The green sheet is formed by applying and drying a slurry on a substrate. As a method for applying the slurry, a known method such as a doctor blade method or an extrusion method can be used. Next, an electrode film is formed on the green sheet by a screen printing method or the like. In the step (7), a plurality of green sheets on which the electrode films are thus formed are stacked to form a stacked body. Next, this laminate is compressed and fired to form a ceramic laminate. The firing temperature can be, for example, 900 ° C. or higher and 1300 ° C. or lower.

  The ceramic laminate thus obtained is cut into a predetermined shape to form a laminate ceramic chip. As shown in FIG. 2, the multilayer ceramic chip includes a ceramic film 32, a first electrode 34 formed on the ceramic film 32, a ceramic film 32, and a second electrode formed on the ceramic film 32. 36. Next, as shown in FIG. 3, a first external electrode 38 connected to the first electrode 34 and a second external electrode 40 connected to the second electrode 36 are formed on the outer periphery of the multilayer ceramic chip. The piezoelectric element 30 is obtained. In the illustrated example, the ceramic film has five layers, but the number of ceramic films can be appropriately selected depending on the piezoelectric element.

4). Manufacturing method of droplet ejecting apparatus The manufacturing method of the droplet ejecting apparatus according to the present embodiment is performed by using the above-described manufacturing method of the piezoelectric element. Hereinafter, a droplet ejecting apparatus manufactured by applying the manufacturing method of the present embodiment will be described with reference to FIG.

  In the droplet ejecting apparatus 100, a liquid such as ink is supplied from the reservoir 14 to the pressure chamber 12. Since the volume of the pressure chamber 12 is variable by the deformation of the diaphragm 50, the volume of the pressure chamber 12 is changed by applying a voltage to the stacked piezoelectric element 30, and the liquid is discharged from the nozzle hole 22. can do. In FIG. 4, a member denoted by reference numeral 16 is a damming portion for controlling the amount of liquid flowing into the pressure chamber 12.

  As a manufacturing method of the droplet ejecting apparatus 100, for example, the following method can be adopted.

  The nozzle plate 20, the substrate 10 and the vibration plate 50 are joined with an adhesive or the like. Next, the piezoelectric element 30 obtained by the manufacturing method of the present embodiment is disposed on the vibration plate 50 on the protrusion 52 of the vibration plate 50 positioned above the pressure chamber 12. The piezoelectric element 30 can be fixed to the spacer 60 fixed to the holding member 70 by means such as adhesion. Next, a flexible wiring board (not shown) is connected to the external electrodes 38 and 40.

  The droplet ejecting apparatus 100 can be used not only as an ink jet printer but also as an industrial liquid ejecting apparatus. As the liquid (liquid material) discharged in this case, various functional materials adjusted to an appropriate viscosity with a solvent or a dispersion medium can be used.

5). Example 5.1. Example 1 (Method for producing ceramic powder)
First, the raw material liquid containing a metal compound was prepared by the following method. In this example, a raw material liquid of PZTN composite metal oxide was prepared. As the metal compound, a solution in which a metal compound of Pb, Zr, Ti, and Nb was dissolved in n-butanol was used. Specifically, lead acetate, zirconium alkoxide, titanium alkoxide, and niobium octylate were used. These were mixed with dimethyl succinate as a polycarboxylic acid ester and n-butanol as an organic solvent. In this example, the metal compound is contained at a rate of 0.5 mol / liter with respect to the raw material liquid.

In this example, each metal compound was mixed so as to have a composition of PbZr _0.2 Ti _0.6 Nb _0.2 O ₃ (PZTN). Furthermore, for the purpose of lowering the crystallization temperature of the composite metal oxide film, silicon alkoxide was added to the raw material composition at a ratio of 3 mol%. The raw material composition was obtained by dissolving these in n-butanol so that the metal compound and dimethyl succinate had a ratio (molar ratio) of 1: 1.

  Then, using a spray drying apparatus (“B290” manufactured by Büch), the raw material liquid is sprayed and dried in the atmosphere at a temperature of 200 ° C. to obtain a first PZTN powder raw material having an average particle size of about 5 μm to 10 μm. It was.

  Next, the obtained first PZTN powder raw material was stirred by a ball mill while being heated at 400 ° C. As a result, the first PZTN powder raw material was in a dry state from which n-butanol was almost removed. At this time, the average particle size of the first PZTN powder raw material was about 1 to 3 μm.

  Next, the first PZTN powder material was further pulverized by a ball mill. As a result, a second PZTN powder material having a particle size of about 100 nm to 1 μm was obtained. This second PZTN powder material had not only a smaller particle size than the first PZTN powder material, but also had a uniform particle size.

5.2. Example 2 (Method for Manufacturing Ceramic Film and Piezoelectric Element)
Using the second PZTN powder raw material obtained in Example 1, a PZTN film and a piezoelectric element were formed by the following method.

  First, the second PZTN powder material was pressurized at 8 mPa (1 t / 10 mmφ) and pre-baked at 700 ° C. for 2 hours to obtain pellet-shaped PZTN. Next, the PZTN pellets were pulverized by a ball mill to obtain PZTN powder having an average particle diameter of about 1 μm.

  Next, 100 g of the obtained PZTN powder, an organic solvent (toluene / butanol = 29.2 ml / 10.3 ml), 4.8 g of polyvinyl butyral as a binder, 0.6 g of diamine as a plasticizer, and a dispersant Then, 1.8 g of dioctyl was pulverized and stirred by a pot mill to obtain a slurry having a viscosity of 200 cps.

  Next, a green sheet was formed using the obtained slurry. Using this green sheet and an Ag—Pd alloy paste, a laminate of the green sheet and the electrode film was obtained. In this example, the number of stacked sheets was 20 layers. The electrode film was formed using screen printing.

  Then, it baked at 1150 degreeC and the laminated body of the PZTN film | membrane and an electrode film was obtained. Furthermore, an external electrode was formed to obtain a piezoelectric element.

When the piezoelectric constant of the obtained piezoelectric element was determined, d ₃₁ was 270 pC / N, d ₃₃ was 550 pC / N, and the Curie temperature (Tc) was about 400 ° C.

5.3. Comparative Example 1
A piezoelectric element was obtained in the same manner as in Example 1 and Example 2 except that bulk PZT obtained using a commercially available sol-gel raw material was used instead of PZTN. When the piezoelectric constant of this piezoelectric element was determined, d ₃₁ was 190 pC / N, d ₃₃ was 400 pC / N, and Tc was about 200 ° C.

  When the piezoelectric constant and the Curie temperature in the piezoelectric elements of Example 2 and Comparative Example 1 were compared, it was confirmed that Example 2 was significantly better than Comparative Example 1.

5.4. Example 3 (Method for producing ceramic powder)
First, the raw material liquid containing a metal compound was prepared by the following method. In this example, a raw material liquid of PZTN composite metal oxide was prepared. As the metal compound, a solution in which a metal compound of Pb, Zr, Ti, and Nb was dissolved in n-butanol was used. Specifically, lead octylate, zirconium alkoxide, titanium alkoxide, and niobium octylate were used. These were mixed with dimethyl succinate as a polycarboxylic acid ester and n-butanol as an organic solvent. In this example, the metal compound is contained at a rate of 0.5 mol / liter with respect to the raw material liquid.

In this example, each metal compound is approximately PbZr _0.48 Ti _0.42 Nb _0. Were mixed so that the composition of O _3. Furthermore, for the purpose of lowering the crystallization temperature of the composite metal oxide film, silicon alkoxide was added to the raw material composition at a ratio of 3 mol%. The raw material composition was obtained by dissolving these in n-butanol so that the metal compound and dimethyl succinate had a ratio (molar ratio) of 1: 1.

  Next, the first PZTN powder raw material having an average particle size of about 0.1 μm or more and 5 μm or less is obtained by spraying and drying the raw material liquid in the atmosphere at a temperature of 130 ° C. using a spray drying apparatus (“B290” manufactured by Büch). Got. The obtained powder raw material was a spherical white powder. The result of thermogravimetric analysis using this powder raw material as a sample is shown in FIG. From FIG. 5, it was found that the sample showed a rapid weight loss at around 270 ° C. and thereafter became almost constant. From this, it was found that the sample had a chemically uniform structure, and the decomposition was instantaneous.

  Next, the obtained first PZTN powder raw material was stirred by a ball mill while being heated at 400 ° C. As a result, the first PZTN powder raw material was in a dry state from which n-butanol was almost removed. At this time, the average particle size of the first PZTN powder raw material was about 1 μm or more and 3 μm or less.

  Next, the first PZTN powder material was further pulverized by a ball mill. As a result, a PZTN powder raw material having a particle size of about 100 nm to 1 μm was obtained. Further, the PZTN powder was heat-treated (pre-baked) at 700 ° C., then finely pulverized by a ball mill, and further heat-treated (pre-fired) at 700 ° C. to obtain a second PZTN powder raw material. This second PZTN powder material had not only a smaller particle size than the first PZTN powder material, but also had a uniform particle size.

  The X-ray analysis result (XRD) of the second PZTN powder is shown in FIG. From FIG. 6, it was confirmed that the PZTN powder after calcination has a perovskite structure.

Subsequently, it was further finely pulverized with a ball mill to obtain a PZTN powder having an average particle size of about 0.5 μm or more and 2 μm or less. To 100 g of this PZTN powder raw material, 3 g of polyvinyl alcohol is added as a binder and granulated, and then pressurized at 8 mPa (1 t / 10 mmφ) and heat treated (fired) at 1270 ° C. for 2 hours to form PZTN in the form of pellets Got. The density of the pellet PZTN was 7.7 (g / cm ³ ). Moreover, FIG. 6 shows the XRD of the PZTN powder after firing. From FIG. 6, it was confirmed that the PZTN powder after firing also has a perovskite structure, like the PZTN powder after temporary firing.

  Furthermore, after polishing the surface of the obtained pellet-like PZTN, electrodes were formed to form a piezoelectric element sample. The piezoelectric element sample was subjected to a poling process, and then the electrical characteristics were measured. The polling conditions were 3 kV / mm at 150 ° C.

The measurement results were as follows. The piezoelectric constant d ₃₃ is 602 (pC / N), the relative dielectric constant εr is 2251, the dielectric loss tan δ is 1.9%, the leakage current is 2 × 10 ⁻⁸ (A / cm ² ), and the Curie point Tc. Was 310 ° C.

When the drying temperature was 200 ° C., it was confirmed that the dielectric loss tan δ was lowered to 8.5%, although the piezoelectric constant d ₃₃ and the relative dielectric constant εr did not change much.

  Furthermore, the composition by ICP emission analysis is shown in FIG. 7 for the raw material liquid, the PZTN powder after spray drying, the PZTN powder after calcination, and the PZTN powder after calcination. From FIG. 7, it was confirmed that the composition ratio of the raw material liquid and the composition ratio of PZTN after firing were almost the same for zirconium, titanium, and niobium, although the molar ratio of lead was slightly reduced.

5.5. Comparative Example 2
PZTN powder was obtained by the solid phase method so that the metal ratio was the same as in Example 3. Specifically, PbO, ZrO ₂ , TiO ₂ and Nb ₂ O ₅ were weighed so as to have a molar ratio of 106: 47: 43: 5, and then mixed and pulverized in a pot mill. The obtained powder was dried and heat-treated (pre-baked) at 700 to 900 ° C. X-ray analysis (XRD) was performed on the powder after heat treatment at 700 ° C. for 2 hours and on the powder after heat treatment at 900 ° C. for 2 hours. The result is shown in FIG. From FIG. 8, it was confirmed that in the solid phase method, the peak of the raw material remained at 700 ° C. to 900 ° C., and it was not possible to obtain perovskite single phase PZTN.

  The present invention is not limited to the above-described embodiments, and various modifications can be made. For example, the present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same functions, methods, and results, or configurations that have the same purposes and effects). In addition, the present invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that achieves the same effect as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

30 Piezoelectric element, 32 Ceramic film, 34, 36 electrode, 38, 40 External electrode

Claims (11)

Preparing a solution containing a metal compound;
Forming a powder from the solution,
The said metal compound is a manufacturing method of ceramic powder containing at least 1 sort (s) of a hydrolysable metal compound and a thermally decomposable organometallic compound. In claim 1,
The metal compound includes a first metal compound containing Pb, a second metal compound containing Zr, a third metal compound containing Ti, and a fourth metal compound containing Nb. . In claim 2,
The first metal compound is lead acetate or lead octylate,
The second metal compound is Ti alkoxide, Ti acetate or Ti octylate,
The method for producing a ceramic powder, wherein the third metal compound is niobium octylate or lead niobium octylate. In any of claims 1 to 3,
The step of forming the powder is a method for producing a ceramic powder, which is performed using a spray drying method or a freeze drying method. In any of claims 1 to 4,
Furthermore, the said solution contains the silicon | silicone, The manufacturing method of the ceramic powder. Forming a slurry from the ceramic powder produced by the method for producing a ceramic powder according to any one of claims 1 to 5,
Forming a film using the slurry;
And a step of firing the film.   A method for manufacturing a piezoelectric element, which uses the method for manufacturing a ceramic film according to claim 6.   A method for manufacturing a droplet ejecting apparatus using the method for manufacturing a piezoelectric element according to claim 7. Preparing a solution containing a metal compound;
Forming a first powder from the solution using a spray drying method or a freeze drying method;
Heating the first powder while stirring to form a second powder;
Pulverizing the second powder to form a third powder;
Forming the first ceramic body by forming and firing the third powder, or forming a slurry from the third powder, and forming and firing;
Crushing the first ceramic body to form a fourth powder;
Forming and firing the fourth powder, or forming a slurry from the fourth powder, forming a film, and firing the method.   The manufacturing method of a piezoelectric element using the manufacturing method of the ceramic film of Claim 9.   A method for manufacturing a droplet ejecting apparatus, which uses the method for manufacturing a piezoelectric element according to claim 10.