JP5190894B2 - Piezoelectric or dielectric ceramic composition, piezoelectric device and dielectric device - Google Patents

Description

  The present invention relates to a piezoelectric or dielectric ceramic composition, particularly a piezoelectric or dielectric ceramic composition having an alkali-containing niobate-based perovskite structure that does not contain lead, and the piezoelectric or dielectric ceramic composition. The present invention relates to a piezoelectric device and a dielectric device.

  Many piezoelectric devices have been developed and applied using the principle (piezoelectric effect) of converting electrical energy of piezoelectric ceramic compositions into mechanical energy or converting mechanical energy into electrical energy.

The piezoelectric ceramic composition constituting the piezoelectric device using these piezoelectric effects is, for example, a piezoelectric ceramic composition (hereinafter referred to as PZT) containing lead composed of two components of PbTiO ₃ —PbZrO ₃ . A piezoelectric ceramic composition having a third component of a piezoelectric ceramic composition such as Pb (Mg _1/3 Nb _2/3 ) O ₃ or Pb (Zn _1/3 Nb _2/3 ) O _{3 with} respect to this PZT. Things exist.
These PZT-based piezoelectric ceramic compositions have high piezoelectric characteristics and are used in most piezoelectric devices using the piezoelectric effect that are currently in practical use.
However, since the piezoelectric ceramic composition containing PZT as a main component contains Pb, there is a problem that the environmental load such as volatilization of PbO during the production process is high.

Therefore, a piezoelectric ceramic composition that does not contain lead or has low lead has been demanded. Under such social demands, research on piezoelectric ceramic compositions containing no lead has been conducted in recent years.
One of the ceramic compositions expected as a piezoelectric ceramic composition not containing lead is KNbO ₃ . This single crystal of KNbO ₃ has been reported to have a large electromechanical coupling constant (see Non-Patent Documents 1 and 2 and Patent Document 1), and is expected to be applied to high-performance piezoelectric devices.

In addition, by introducing a perovskite type compound composed of a rare earth metal element and a transition metal element or aluminum which becomes a trivalent cation to KNbO ₃ , the sinterability is improved (Patent Document 2), Bi It has been invented that deliquescence is suppressed by adding or Mn (Patent Document 3).

Additionally, expressed in Patent Document At 4, the general formula _{{Li x (K 1-y} Na y) 1-x} (Nb 1-z-n Ta z (Mn 0.5 W 0.5) n) O 3 And x, y, z, and n are in the composition ranges of 0 ≦ x ≦ 0.2, 0 ≦ y ≦ 1.0, 0 ≦ z ≦ 0.4, and 0 <n ≦ 0.1, respectively. A piezoelectric ceramic composition is proposed.

Further, the invention described in Patent Document 5, (1-n) (Ag 1-abc Li a Na b K c) (Nb 1-xyz Ta x Sb y V z) O 3 + nM1M2O 3 ( where, 0 ≦ a ≦ 0.2, 0 ≦ b ≦ 0.95, 0 ≦ c ≦ 0.95, 0 <(1-abc) ≦ 1, 0 ≦ x ≦ 0.5, 0 ≦ y ≦ 0. 2, a piezoelectric / electrostrictive porcelain composition mainly composed of a binary solid solution represented by 0 ≦ z ≦ 0.2, 0 ≦ (y + z) ≦ 0.3, 0 ≦ n ≦ 0.2) M1 and M2 are metal elements that satisfy a predetermined condition, and examples of the predetermined condition include solid solution compositions with various composite perovskite compounds.

K. Yamanouchi, H .; Odagawa, T .; Kojima and T.K. Matsumura. Electron. Lett. , 33 (1997), 193. K. Nakamura and Y.M. Kawamura. IEEE Trans. Ultrason. Ferrolectr. Feq. Control. 47 (2000), 450.

JP 2003-17981 A JP 2004-359539 A JP 2005-281413 A JP 2003-342071 A JP 2006-124271 A

As described above, KNbO ₃ improves sinterability or suppresses deliquescence, and also substitutes the A site with a monovalent alkali metal element or Ag, and the B site with a pentavalent metal element. Alternatively, replacement with a metal element having a total valence of pentavalent is expected to be applied to a piezoelectric device.
However, for example, in the invention of Patent Document 4, only a combination of Mn of the tetravalent metal element and W of the hexavalent metal element is described, and attempts to dissolve other composite perovskite compounds are described. However, other possible combinations of the B site composition with a total valence of 5 are completely unknown.

Furthermore, it is necessary to develop lead-free piezoelectric ceramic compositions mainly composed of KNbO ₃ having high characteristics by evaluating the electrical characteristics and piezoelectric characteristics of a solid solution composition with a large number of composite perovskite compounds.
In the composition described in Patent Document 5, efforts are made to dissolve a large number of complex perovskite compounds, but Ag is an essential element. Piezoelectric porcelain composition that is A ¹⁺ B ⁵⁺ O _{3 in} which Ag conforms to the A site has a lower specific resistivity and lower reliability than a case where no Ag is contained, and is a practical piezoelectric body. It is extremely difficult to make a porcelain composition, and if it is an electrostrictive porcelain composition, a piezoelectric effect cannot be obtained and it cannot be used as a piezoelectric device.

An object of the present invention is to solve the above-mentioned problems and to provide a novel composite perovskite compound in a piezoelectric or dielectric ceramic composition represented by A ¹⁺ B ⁵⁺ O ₃ containing KNbO ₃ as a main component In order to obtain a piezoelectric or dielectric ceramic composition having good dielectric characteristics and piezoelectric characteristics by dissolving the solution, it is possible to meet a wide range of demands for the development of piezoelectric devices and dielectric devices. It is to replace the piezoelectric or dielectric ceramic composition as a component and reduce the environmental load.

In the present invention, the following means are adopted in order to solve the above problems.
(1) The main component is a piezoelectric or dielectric ceramic composition represented by the composition formula (1-x) KNbO ₃ + xKMeO ₃ , wherein 0 <x ≦ 0.05, and Me is a tetravalent Ti It is a combination of any metal element selected from trivalent Mn, bivalent Mn, and divalent Zn, and hexavalent W, and the total valence when combined is pentavalent A piezoelectric or dielectric ceramic composition.
Thus, with respect to the piezoelectric or dielectric ceramic composition containing KNbO ₃ as the main component, the A site is composed of a monovalent metal element, and the B site is composed of a metal element having a total valence of A ¹⁺ B By dissolving 5 ⁺ O ₃ type perovskite, it is possible to increase the relative dielectric constant as compared with the conventional piezoelectric or dielectric ceramic composition containing KNbO ₃ .

(2) The piezoelectric or dielectric ceramic composition according to (1) above, wherein Mn is contained as an auxiliary component in an amount of 1.0 to 2.0 mol in terms of MnO when the main component is 100 mol. It is.
A ceramic composition obtained by mixing a predetermined amount of Mn as a subcomponent with a main component and then firing it can suppress dielectric loss as compared with a piezoelectric or dielectric ceramic composition in which Mn is not mixed.

(3) The piezoelectric or dielectric ceramic composition according to (2), wherein the composition formula is (1-x) KNbO ₃ + xK (Zn _1/4 W _3/4 ) O ₃ .
When the main component is (1−x) KNbO ₃ + xK (Zn _1/4 W _3/4 ) O ₃ , satisfies the range of 0 <x ≦ 0.05, and the main component is 100 mol, A piezoelectric ceramic composition containing 1.0 to 2.0 mol of Mn as a component in terms of MnO can obtain piezoelectric characteristics that greatly exceed KNbO ₃ , particularly when 0 <x ≦ 0.03. Become. Further, even when the piezoelectric characteristic does not exceed the KNbO _3, than KNbO _3, high relative dielectric constant, since the dielectric loss is stable, it is excellent as a dielectric ceramic composition.

Wherein the (1) to (3), in the composition formula, by at least one K of KNbO ₃ is selected only from Li and Na, some substituted you characterized by being pressure collector or dielectric including the body porcelain composition.
Further, in the composition formula, including the Nb of KNbO ₃ is Ta alone, some pressure collector that you characterized substituted or dielectric ceramic composition.
As described above, the piezoelectric or dielectric ceramic composition of the present invention that forms an ABO ₃ type perovskite compound can take a monovalent metal element at the A site and a pentavalent metal element at the B site. It is possible to partially replace K at the A site with Na and Li, and partially replace Nb at the B site with Ta.

(4) The piezoelectric ceramic composition according to any one of (1) to (3), wherein the first electrode and the second electrode are opposed to each other with the piezoelectric ceramic layer interposed therebetween. It is a piezoelectric device characterized by being formed of an object.
(5) The first electrode and the second electrode are alternately stacked in a plurality of layers via the piezoelectric ceramic layer, and a first terminal electrode electrically connected to the first electrode; The piezoelectric device according to (4) , further comprising a second terminal electrode electrically connected to the second electrode.
(6) In a dielectric device comprising a plurality of dielectric ceramic layers, an internal electrode formed between the dielectric ceramic layers, and an external electrode electrically connected to the internal electrode, the dielectric ceramic layer comprises: A dielectric device characterized by being formed of the dielectric ceramic composition according to any one of (1) to (3) .
In particular, the piezoelectric ceramic composition of the present invention can be used in various piezoelectric devices such as piezoelectric sounding bodies, piezoelectric sensors, piezoelectric actuators, piezoelectric transformers, and piezoelectric ultrasonic motors.
At present, PZT is used in these piezoelectric devices. By substituting this with the piezoelectric ceramic composition of the present invention, PbT is eluted from PZT and diffuses to the environment due to acid rain or the like. Can be prevented.

In the present invention, the piezoelectric or dielectric ceramic composition containing KNbO ₃ as the main component, a monovalent metal element A site, the B site total valence consisting pentavalent metal element A ¹⁺ By dissolving the B ⁵⁺ O ₃ type perovskite in a solid solution, it is possible to increase the relative dielectric constant as compared with the conventional piezoelectric ceramic composition containing KNbO ₃ .
Dielectric loss can be suppressed by mixing a predetermined amount of Mn as a subcomponent in the main component. It is possible to suppress dielectric loss when using the piezoelectric body or dielectric ceramic composition in various electronic devices, even when the electric field strength is increased. For example, compared to the piezoelectric ceramic composition, If a high electric field strength can be applied to the resulting ceramic, a large amount of displacement can be obtained. For example, in a ceramic made of a dielectric ceramic composition, heat generation is suppressed when an alternating current is applied, It is possible to prevent the element from being destroyed by heat generation.
The main component is (1−x) KNbO ₃ + xK (Zn _1/4 W _3/4 ) O ₃ , satisfies the range of 0 <x ≦ 0.05, and the main component is 100 mol. In addition, a piezoelectric ceramic composition containing 1.0 to 2.0 mol of Mn as a subcomponent in terms of MnO can obtain piezoelectric characteristics that greatly exceed KNbO ₃ .
Furthermore, since it is possible to manufacture without considering the volatilization of PbO or the like in the manufacturing process, it is possible to mass-produce PbO without managing the volatilization, and to reduce the environmental load. A dielectric ceramic composition can be provided.

It is a PE hysteresis curve of a piezoelectric ceramic composition containing 1.0 mol of Mn in terms of MnO when 0.99 KNbO ₃ -0.01K (Zn _1/4 W _3/4 ) O ₃ is 100 mol. .

The present invention is a piezoelectric or dielectric ceramic composition whose main component is represented by the composition formula (1-x) KNbO ₃ + xKMeO ₃ , wherein 0 <x ≦ 0.05, and Me is a tetravalent It is a combination of any metal element selected from Ti, trivalent Mn, divalent Mn, and divalent Zn and hexavalent W, and the total valence when combined is pentavalent. The piezoelectric or dielectric ceramic composition is characterized.

A piezoelectric ceramic composition satisfying the composition formula can increase the relative dielectric constant of KNbO ₃ which is expected as a lead-free piezoelectric ceramic composition.
Therefore, these compositions can be usefully used as piezoelectric ceramic compositions for piezoelectric devices that increase the relative dielectric constant and increase the amount of displacement, such as piezoelectric sounding bodies and piezoelectric actuators.
Further, by increasing the relative dielectric constant, it can be useful not only as a piezoelectric ceramic composition but also as a dielectric.
Therefore, these compositions can be usefully used for dielectric devices such as capacitors.

Increasing the relative dielectric constant becomes possible when the piezoelectric ceramic composition or the dielectric ceramic composition having the above composition formula is combined so that the total valence is five.
That is, in the combination of Ti, which is a tetravalent metal element, and W, which is a hexavalent metal element, (Ti _1/2 W _1/2 ), Mn which is a trivalent metal element and hexavalent metal In the combination with W which is an element, it is (Mn _1/3 W _2/3 ), and in the combination of Mn which is a divalent metal element and W which is a hexavalent metal element, (Mn _1/4 W _3/4 ), and the combination of Zn, which is a divalent metal element, and W, which is a hexavalent metal element, is (Zn _1/4 W _3/4 ).
The combination can achieve the above-described effect of increasing the dielectric constant by at least one combination.
However, if 0.05 <x, the insulation could not be kept extremely, and the piezoelectric ceramic composition and the dielectric ceramic composition with high reliability could not be obtained.

Furthermore, in the case where the main component is 100 mol, by adding 1.0 to 2.0 mol of Mn as a subcomponent in terms of MnO, it is compared with a piezoelectric ceramic composition or a dielectric ceramic composition in which Mn is not mixed. Thus, dielectric loss can be suppressed. As a result, it is possible to prevent dielectric breakdown during the polarization treatment, and it is possible to easily manufacture a piezoelectric body or a dielectric body.
In order to obtain the effect of Mn, even if Mn exists in the grain boundary of the polycrystalline structure of the ceramic that is the piezoelectric ceramic composition or the dielectric ceramic composition of the present invention, Even if it does, it is possible to obtain an equivalent effect.
When the content is less than 1.0 mol, the effect of containing Mn cannot be obtained, and when the content is more than 2.0 mol, the specific resistivity is decreased, and sufficient polarization treatment is performed. I can't do it.

Further, the present invention forms a ABO ₃ type perovskite compound, in the composition formula, by at least one K in the A site is selected only from Li and Na, partially substituted, or, Nb in the B site is only Ta The piezoelectric ceramic composition and the dielectric ceramic composition that are partially replaced by the above are included.
Thus, by adjusting the elements conforming to the A site and the elements conforming to the B site, for example, the crystal phase of KNbO ₃ from 200 ° C. to 220 ° C. from orthorhombic to tetragonal The transition can be controlled to room temperature or lower, or the crystal phase transition from a tetragonal crystal to a cubic crystal existing at about 400 ° C., that is, the Curie temperature can be further increased or decreased.

  In the piezoelectric or dielectric ceramic composition of the present invention, at least one type of Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, which are the first transition elements, is mixed in a certain amount. Although it is possible to control the sintering temperature, to control the growth of particles, and to extend the lifetime in increasing the electric field, these elements may or may not be used.

  In addition, the piezoelectric or dielectric ceramic composition according to the present invention is mixed with at least one kind of second transition elements Y, Zr, Mo, Ru, Rh, Pd, and Ag in a certain amount, thereby reducing the sintering temperature. These elements can be controlled, particle growth can be controlled, and the lifetime in high electric field can be extended. However, these elements may or may not be used.

  Further, the piezoelectric or dielectric ceramic composition according to the present invention includes La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, which are third transition elements. By mixing a certain amount of at least one kind of Hf, W, Re, Os, Ir, Pt, and Au, the sintering temperature can be controlled, the growth of particles can be controlled, and the life in the high electric field can be extended. Although possible, these elements may or may not be used.

  And by mixing a certain amount of at least one of the first transition elements, second transition elements, and third transition elements shown above, the sintering temperature can be controlled, the growth of particles can be controlled, Although it is possible to extend the lifetime in the process, the same effect can be obtained with or without combining them.

In the raw material (material) for realizing the piezoelectric or dielectric ceramic composition of the present invention, the material containing potassium is K ₂ CO ₃ or KHCO ₃ and the material containing sodium is as follows: Na ₂ CO ₃ to NaHCO ₃ , Li ₂ CO ₃ as the material containing lithium, Nb ₂ O ₅ as the material containing niobium, and Ta ₂ as the material containing tantalum O ₅ , a material containing tungsten is WO ₃ to K ₂ WO ₄ to Na ₂ WO ₄ , and a material containing titanium is TiO ₂ to K ₂ Ti ₆ O ₁₃ , and Mn as the element containing, to no MnO, to _Mn 2 _{O 3} not, to _Mn 3 _{O 4} not, to MnO ₂ no, to MnCO _{3 no,} a K 2 MnO ₄ And a MnNb ₂ O _6, as the element containing zinc, to no ZnO, or the like can be used ZnNb ₂ O _6.

By using such raw materials, steps such as easy blending, stirring, and calcining can be performed, and synthesis can be performed without giving a load to production.
In the present invention, calcination is preferably performed at 700 to 900 ° C., and calcination is preferably performed at 900 to 1100 ° C.

The piezoelectric or dielectric ceramic composition of the present invention has a perovskite structure generally indicated as ABO ₃ . Here, the elements conforming to A are K, Na, and Li, and the elements conforming to B are Nb and Ta. When the stoichiometry is A: B = 1: 1, the elements are ideally conformed completely at all site positions, and a stable structure is obtained. However, as is apparent from the constituent elements of the composition, elution of K, Na, Li due to moisture, volatilization of K, Na, Li in the calcination process, volatilization of K, Na, Li in the firing process In the end, the variation of the composition is about several percent, specifically 2% or less. Variations in these constituent elements can occur due to changes in the raw materials, synthesis time, and synthesis process.
In order to cope with these fluctuations, for example, a large amount of raw materials that are sources of K, Na, and Li in the initial blend are intentionally included, and A: B = 1: 1 is ideal after the final step, that is, the firing step. Approach to a new state is taken as a method.

In order to obtain a ceramic having a high piezoelectric effect, it is desirable to place the final ratio of A site and B site within the range of 0.96 <A / B <1.002.
Such an intentional adjustment of the amount of elements in the initial blend is a general technique performed in the synthesis of most ceramics.

  In the ceramic that is the piezoelectric or dielectric ceramic composition obtained by the present invention, the relative density of the sintered body is desirably 95% or more. By adjusting in such a manner, it is possible to prevent the deterioration of characteristics over time.

  Using the piezoelectric ceramic composition of the present invention, a piezoelectric ceramic layer in a piezoelectric device in which the first electrode and the second electrode are opposed to each other through the piezoelectric ceramic layer can be formed. In the piezoelectric device, the first electrode and the second electrode are alternately stacked in a plurality of layers via the piezoelectric ceramic layer, and the first terminal electrode electrically connected to the first electrode And a second terminal electrode electrically connected to the second electrode.

  The piezoelectric device may be manufactured by a conventional method. That is, first, a ceramic green sheet is formed by a doctor blade method using a ceramic slurry that forms the piezoelectric ceramic composition of the present invention. Next, a conductor paste containing Ag / Pd or the like for forming the first electrode and the second electrode is printed on the upper surface of the green sheet. Thereafter, green sheets on which conductor paste is printed are laminated, and green sheets on which conductor paste is not printed are further laminated on the upper and lower layers, and these are pressure-bonded. Next, after firing the laminated body to obtain an element body, Ag or the like is vapor-deposited on a predetermined side surface of the element body to form a first terminal electrode and a second terminal electrode, thereby obtaining a piezoelectric device.

The piezoelectric device having the above-described configuration is a piezoelectric device that exists between the first electrode and the second electrode due to the piezoelectric effect when an AC voltage is applied between the first terminal electrode and the second terminal electrode. Polarization occurs in the ceramic layer, and strong mechanical vibration is generated in synchronization with the change in voltage polarity. Here, the vibration direction of the piezoelectric ceramic plate is parallel to the surface of the piezoelectric ceramic plate and is orthogonal to the first electrode and the second electrode stacked in a plurality of layers. That is, to generate the vibration by the piezoelectric constant _{d 33.}

A dielectric device comprising a plurality of dielectric ceramic layers, an internal electrode formed between the dielectric ceramic layers, and an external electrode electrically connected to the internal electrode using the dielectric ceramic composition of the present invention A dielectric ceramic layer can be formed.
The dielectric device as described above may be manufactured by a conventional method. That is, first, a ceramic green sheet is formed by a doctor blade method using a ceramic slurry that forms the dielectric ceramic composition of the present invention. Next, an internal electrode paste containing Ni or the like is printed on the green sheet, and after lamination and pressure bonding, it is cut into a predetermined shape. Thereafter, a binder treatment is performed in an inert atmosphere, an external electrode paste containing Ni or the like is applied to a predetermined side surface, firing is performed in a reducing atmosphere, and a re-oxidation treatment is performed, whereby a dielectric device (multilayer ceramic) Capacitor) is obtained.
The best mode for carrying out the invention will become apparent from the following examples.

Example 1
In order to verify the effects of the piezoelectric or dielectric ceramic composition of the present invention, first, the compositions as shown in Table 1 were evaluated.
Sample No. For No. 1, KNbO ₃ was evaluated for comparison. Sample No. About 2-5, the B site metal element in a composition type | formula was evaluated about the sample adjusted variously so that it might become the total valence 5.
Sample No. No. 1 is a composition outside the scope of the present invention. About 2-5, it is a composition within the scope of the present invention.

Sample No. The piezoelectric or dielectric ceramic composition shown in 1 to 5 was produced by the following method, and the electrical properties were measured.
As raw materials, K ₂ CO ₃ (or KHCO ₃ ), Nb ₂ O ₅ , ZnO, MnO, Mn ₂ O ₃ , TiO ₂ , and WO ₃ having a purity of 99% or more were prepared. A composition satisfying the stoichiometric ratio shown in Sample No. was weighed, mixed with a wet ball mill, and molded into a cylindrical sample having a diameter of 20 mm.
And this sample made into this columnar sample was pre-baked suitably at the temperature of 700-900 degreeC on the conditions of holding time 2 to 4 hours. After the calcined columnar sample was crushed, it was crushed again by a wet ball mill.

After the pulverized powder was dried, it was pulverized and mixed for 1 hour using an alumina mortar. The mixed powder is passed through a sieve having an opening of 150 μm, and the classified powder sample is weighed by about 2.0 g per pellet, and is applied to a carbon die for a spark plasma sintering method (SPS method: Spark Plasma Sintering Method) having a diameter of 15 mm. Filled. Sintering was performed using the SPS method, and sintering was performed under the conditions of a temperature of 800 to 975 ° C., a temperature raising / lowering rate of 50 ° C./min, a pressure of 30 MPa, and a holding time of 10 minutes.
The sample produced by the SPS method was polished using an automatic precision cutting / polishing apparatus until the thickness became about 1.0 mm. The polished sample was subjected to heat treatment at 800 ° C. for 4 hours in the atmosphere as re-oxidation treatment after removing the oil content of the wax used for polishing.

For the sample prepared by the above steps, after baking the high temperature Ag paste on the surface of the sample at 700 ° C. for measuring the electrical properties, the relative dielectric constant (ε) and dielectric loss (tan δ) at 30 ° C. and 100 ° C. It was measured.
Table 2 shows the measurement results.

Comparative Example of Sample No. 1 in Table 2 and Sample No. Regarding No. 4, the dielectric loss (tan δ) diverged abnormally at 30 ° C., and the relative dielectric constant could not be measured correctly.
With respect to the samples No. 2 to 5, the relative permittivity is increased in comparison with the sample No. 1 as a comparative example at least at 30 ° C. or 100 ° C. It was found that the rate was improved so that it could be measured.
Moreover, the effect in these sample Nos. 2-5 can acquire the same effect also by combining at least 1 composition of sample No.2-5.
Furthermore, when the relative permittivity and dielectric loss were confirmed by the same method for the piezoelectric or dielectric ceramic composition in the composition range of the present invention other than these sample Nos. 2 to 5, the same effect was obtained. It was confirmed that

(Example 2)
Moreover, in order to verify the effect at the time of mixing Mn as a subcomponent about the piezoelectric material or dielectric ceramic composition shown above, the following experiment was conducted.
1.0 mol MnO is added to 100 mol of the pulverized powder after calcining obtained in Example 1 and mixed by a wet ball mill, followed by drying to obtain the target piezoelectric or dielectric ceramic. A mixed powder of the composition was obtained.
Table 3 shows the composition of the obtained mixed powder.

As in Example 1, 2.0 g of the mixture was weighed, filled in a carbon die for SPS method having a diameter of 15 mm, fired by SPS method, further polished to a thickness of 1.0 mm, Ag The paste was baked to obtain a sample to be evaluated.
For the obtained sample Nos. 6 to 9, the relative dielectric constant (ε) and the dielectric loss (tan δ) were measured.
Table 4 shows the measurement results.

According to the results shown in Table 4, No. MnO was not introduced as a subcomponent, respectively. Compared with the samples 2-5, no. It was found that the samples 6 to 9 had a low dielectric loss.
Therefore, introduction of 1.0 mol of MnO as a subcomponent with respect to 100 mol of the main component causes heat generation during driving when the piezoelectric or dielectric ceramic composition is used as a piezoelectric device or dielectric device. It is possible to hold down and prevent insulation deterioration at high voltage, which is useful as an electronic device.
Further, relative dielectric constant and dielectric loss when introducing Mn as a subcomponent by the same method for the piezoelectric or dielectric ceramic composition other than these sample Nos. 6 to 9 within the composition range of the present invention. As a result, it was confirmed that there was an equivalent effect.

(Example 3)
From the above knowledge, 0.95 KNbO ₃ -0.05K (Zn _1/4 W ₃ //) was judged to have good reliability because it had the highest relative dielectric constant and low dielectric loss. ₄ ) The sample No. 9 containing MnO as a sub-component with respect to 100 mol of O ₃ could be easily polarized. Therefore, the experiment was advanced in the same manner as shown in Example 1 and Example 2 according to the composition of Table 5 as follows.

About the sample produced by the process similar to Example 1 and Example 2, Ag paste for high temperature was baked on the sample surface at 700 degreeC for the electrical property measurement. Thereafter, the relative dielectric constant (ε) and dielectric loss (tan δ) were measured at 30 ° C.
And the ferroelectric PE hysteresis of the obtained sample was measured and ferroelectricity was evaluated. Further, after applying a polarization treatment by applying a DC voltage in silicon oil at 150 ° C. at 3 kV / mm for 10 minutes, the piezoelectric constant d ₃₃ value is measured using a d ₃₃ meter to evaluate piezoelectric characteristics at a room temperature of 30 ° C. did.
In FIG. The PE hysteresis curves for 11 samples are shown.
Table 6 shows values of relative dielectric constant (ε), dielectric loss (tan δ), and piezoelectric characteristic d ₃₃ at 30 ° C. for sample Nos. 10 to ₁₅ .

Sample No. In 10, it was possible to obtain a high dielectric constant and d ₃₃ properties. Since the relative dielectric constant is as high as 1180, it is excellent as a dielectric ceramic composition.
Sample No. In 11, a low dielectric loss high dielectric constant, it was possible to obtain a high d ₃₃ properties. In general, the d ₃₃ characteristic of KNbO ₃ is about 90 to 95 pC / N, and a piezoelectric ceramic composition having much higher piezoelectric characteristics than that can be obtained.

Further, as seen in FIG. No. 11 porcelain composition shows good PE hysteresis, and it can be seen that the present piezoelectric porcelain composition is an excellent piezoelectric substance.
Similarly, excellent piezoelectric characteristics can be obtained also in sample No. 12.
Since sample No. 13 has a high relative dielectric constant of 885, it is excellent as a dielectric ceramic composition.
Furthermore, even in the compositions of Samples No. 14 and No. 15 in which the content of MnO is increased from Sample No. 13, the relative dielectric constant is generally higher than that of KNbO ₃ and the dielectric loss is also the comparative sample No. 1 sample. It was revealed that the piezoelectric ceramic composition or the dielectric ceramic composition is highly reliable and excellent.
In addition, all the samples in this example are (1-x) KNbO ₃ -xK (Zn _1/4 W _3/4 ) O _{3 as} main components, satisfy the range of 0 <x ≦ 0.05, and When the main component is 100 mol, it is within the range of a piezoelectric ceramic composition or a dielectric ceramic composition containing 1.0 to 2.0 mol of Mn as a subcomponent in terms of MnO.
Further, these sample Nos. When piezoelectric characteristics and dielectric characteristics of piezoelectric ceramic compositions or dielectric ceramic compositions within the composition range of the present invention other than 10 to 15 are measured by the same method, it is confirmed that the same effects are obtained. I was able to.

Claims (6)

The main component is a compositional formula (1-x) KNbO ₃ (K is partially substituted by at least one selected from Li and Na only, or Nb is partially substituted only by Ta the included) a piezoelectric or dielectric ceramic composition represented by + xKMeO _3, 0 <a x ≦ 0.05, Me is tetravalent Ti, 3-valent Mn, 2 divalent Mn and 2 A piezoelectric or dielectric ceramic composition, which is a combination of any metal element selected from Zn of a valence and hexavalent W, and has a total valence of 5 when combined.   2. The piezoelectric or dielectric ceramic composition according to claim 1, wherein 1.0 to 2.0 mol of Mn in terms of MnO is contained as a subcomponent when the main component is 100 mol. _3. The piezoelectric or dielectric ceramic composition according to claim 2, wherein the composition formula is (1-x) KNbO ₃ + xK (Zn _1/4 W _3/4 ) O ₃ . In the piezoelectric device and the first electrode and the second electrode are opposed through the piezoelectric layer, the piezoelectric ceramic layer is a piezoelectric ceramic composition according to any one of claims 1 to 3 A piezoelectric device characterized by being formed. The first electrode and the second electrode are alternately stacked in a plurality of layers via the piezoelectric ceramic layer, and the first terminal electrode electrically connected to the first electrode and the second electrode The piezoelectric device according to claim 4 , further comprising a second terminal electrode electrically connected to the electrode. A dielectric device comprising a plurality of dielectric ceramic layers, an internal electrode formed between the dielectric ceramic layers, and an external electrode electrically connected to the internal electrode, wherein the dielectric ceramic layer comprises: A dielectric device comprising the dielectric ceramic composition according to claim 3 .