JP2011184247A - Barium titanate-based ceramic powder and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a barium titanate-based ceramic powder which has a structure with a modified surface layer in which a subcomponent exists mostly only in a part near a surface layer of a BaTiO<SB>3</SB>particle and exists hardly near the particle center, and which enables to realize a ceramic capacitor with a surface layer increased and with good capacitance temperature characteristics and excellent reliability (high temperature load life of insulation resistance (IR)), and a method for producing the ceramic powder. <P>SOLUTION: A BaTiO<SB>3</SB>particle is etched to elute Ba in a surface layer of the BaTiO<SB>3</SB>particle, thereby forming a BaTiO<SB>3</SB>particle containing excess Ti, and a compound of at least one selected from the group consisting of Ca, Sr and Mg (subcomponent) is added to the BaTiO<SB>3</SB>particle containing excess Ti and reacted with the BaTiO<SB>3</SB>particle containing excess Ti. The subcomponent in a dissolved state is reacted with the BaTiO<SB>3</SB>particle containing excess Ti (solid-liquid reaction takes place). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a ceramic powder and a method for producing the same, and more particularly to a barium titanate ceramic powder used for a ceramic capacitor and the like and a method for producing the same.

  One of ceramic electronic components widely used in recent years is a multilayer ceramic capacitor. In this multilayer ceramic capacitor, for example, as shown in FIG. 2, an internal electrode 12 disposed inside a multilayer ceramic element (ceramic sintered body) 10 is laminated via a ceramic layer 11 which is a dielectric layer. In addition, a pair of external electrodes 13a and 13b are arranged on both end faces of the multilayer ceramic element 10 so as to be electrically connected to the internal electrodes 12 exposed on the opposite end face.

  The ceramic sintered body constituting the dielectric layer of such a multilayer ceramic capacitor has a good capacity-temperature characteristic, and a viewpoint to realize a ceramic capacitor excellent in reliability (insulation resistance (IR) high temperature load life). Therefore, a ceramic sintered body made of crystal particles having a core-shell structure is desirable. The core-shell structure refers to a form (structure) in which the subcomponent exists only in a portion close to the surface layer of the crystal grain and does not exist near the center of the grain.

  By the way, in order to make the subcomponent exist only in the vicinity of the surface layer, it is conceivable to control the firing conditions first. However, even if the firing conditions are controlled, the state of the solid solution of the subcomponents in the crystal particles tends to be unstable, and the inter-particle variation of the core-shell structure becomes large, which is sufficient as a dielectric material constituting the multilayer ceramic capacitor. It is difficult to obtain a reliable ceramic powder.

  Therefore, as a ceramic powder capable of solving such problems, the particle surface of barium titanate having an average particle diameter of 0.1 to 1 μm and a Ba / Ti (molar ratio) of 0.997 to 1.003. Has been proposed that is coated with 0.0001 to 0.1 mole of titanium oxide per mole of barium titanate (see Patent Document 1).

The titanium-coated barium titanate powder of Patent Document 1 has high titanium dispersibility, and reduces the uneven distribution of titanium, which tends to be a problem when adding titanium oxide to barium titanate, thereby improving the characteristics. It is supposed to be possible.
However, in the case of the powder of Patent Document 1, there is a problem that the natural surface of the BaTiO ₃ particles immediately after synthesis (the surface layer if grasped a little wider) cannot be uniformly modified.

In addition, since the subcomponent is only attached to the surface of the BaTiO ₃ particles, the subcomponent does not necessarily dissolve into the crystal particles homogeneously at the time of firing (in terms of homogeneity, the subcomponent is added as a powder) In fact, the problem of uneven distribution of titanium has not necessarily been sufficiently solved.

JP-A-11-147716

  The present invention solves the above-mentioned problems, and most of the subcomponents are present only in the portion close to the surface layer of the BaTiO3 particles, and have a core-shell structure that is hardly present near the center of the particles, and the capacity-temperature characteristics are An object of the present invention is to provide a barium titanate-based ceramic powder that can realize a ceramic capacitor that is excellent and has high reliability (insulation resistance (IR) high-temperature load life) and a method for producing the same.

The method for producing the barium titanate-based ceramic powder of the present invention comprises:
By etching the (a) BaTiO ₃ particles, eluting the BaTiO ₃ particles surface Ba, the etching process for the Ti excess BaTiO ₃ particles,
(b) a compound addition step of adding at least one compound selected from the group consisting of Ca, Sr, and Mg to the Ti-rich BaTiO ₃ particles;
(c) a reaction step of reacting the compound added in the step (b) with the Ti-excess BaTiO ₃ particles.

In the method for producing the barium titanate ceramic powder of the present invention,
The compound addition step of (b), the in BaTiO ₃ particle dispersion of BaTiO ₃ particles etched dispersed in an aqueous dispersion medium in the step of (a), Ca, Sr, and at least selected from the group consisting of Mg A step of dissolving one kind of compound, and the reaction step (c) is a solution in which at least one compound selected from the group consisting of Ca, Sr and Mg is dissolved in the BaTiO ₃ particle dispersion at room temperature. Alternatively, it is desirable to make the compound react with the Ti-rich BaTiO ₃ particles by stirring at a temperature exceeding room temperature.

In the barium titanate-based ceramic powder of the present invention, at least one compound selected from the group consisting of Ca, Sr, and Mg is present on the surface of Ti-rich BaTiO ₃ particles, and at least the excess molar number of Ti of the BaTiO ₃ particles. The ratio is such that the number of moles corresponds to the above, and is maintained in a state of reacting with the surface of the BaTiO ₃ particles.

Method for producing a barium titanate powder of the present invention, by etching the BaTiO ₃ particles are eluted BaTiO ₃ particles surface Ba, the Ti excess BaTiO ₃ particles, in the Ti excess BaTiO ₃ particles, Ca At least one compound (subcomponent) selected from the group consisting of Mg, Sr, and Mg is added and reacted with Ti-rich BaTiO ₃ particles, so that the subcomponents are simply attached to the surface of the BaTiO ₃ particles. Thus, the surface layer of the BaTiO ₃ particles having a perovskite structure can be reliably modified as compared with the case where the surface of the BaTiO ₃ particles is coated. Further, since Ba is eluted by etching, the Ba / Ti ratio is Ti-rich in the surface layer of the BaTiO ₃ particles, and the subcomponents (Ca, Sr, and Mg compounds) are likely to react. since it is in the state, the auxiliary components by sufficiently react on the surface of the BaTiO ₃ particles, it is possible to reliably reform the surface of the BaTiO ₃ particles.

  Therefore, by using the barium titanate-based ceramic powder produced by the method of the present invention as a dielectric material, a ceramic capacitor having good capacitance temperature characteristics and excellent reliability (insulation resistance (IR) high temperature load life) Can be realized.

  In the present invention, various acids can be used as an etchant for etching the BaTiO 3 particles. And as an acid, hydrochloric acid, a sulfuric acid, nitric acid, an acetic acid etc. can be used, for example.

Further, the compound addition step is carried out by dissolving at least one compound selected from the group consisting of Ca, Sr, and Mg in a BaTiO ₃ particle dispersion in which etched BaTiO ₃ particles are dispersed in an aqueous dispersion medium. The reaction step is carried out by stirring a solution prepared by dissolving at least one compound selected from the group consisting of Ca, Sr, and Mg in a BaTiO ₃ particle dispersion at room temperature or a temperature exceeding room temperature. In this case, the dissolved subcomponent can be uniformly reacted with the surface of the BaTiO ₃ particles by a solid-liquid reaction to cause solid solution, and the present invention can be further effectively realized.

That is, when reacting the subcomponent with the BaTiO ₃ particles, the solid phase subcomponent is caused to react with the surface of the BaTiO ₃ particles in the same solid phase by performing heat treatment (reacting the solids). It is possible, however, to react in a dissolved state (solid-liquid reaction) allows a uniform reaction to proceed from any part of the natural surface of BaTiO ₃ particles having a perovskite structure, Homogeneous surface layer modification can be performed.

Further, the barium titanate-based ceramic powder of the present invention has Ca, Sr on the surface of BaTiO ₃ particles in which Ti constituting the B site is excessive when BaTiO ₃ that is a composite oxide is represented by the general formula ABO _3. and at least one compound selected from the group consisting of Mg (subcomponent), in proportions such that the molar number corresponding to the excessive number of moles of Ti of at least BaTiO ₃ particles and reacts with the surface of the BaTiO ₃ particles The barium titanate-based ceramic powder of the present invention is made from BaTiO ₃ particles whose surface layer is modified, in which subcomponents exist only in portions close to the surface layer of the crystal particles. By using it, it is possible to realize a ceramic capacitor with excellent capacitance-temperature characteristics and excellent reliability (insulation resistance (IR) high-temperature load life). .

The method of manufacturing a barium titanate-based ceramic powder according to an embodiment of the present invention, BaTiO ₃ and the surface of the auxiliary component is solid-liquid reaction of the particles, a process of forming a BaTiO ₃ particles was modified surface layer schematically FIG. It is a figure which shows an example of the multilayer ceramic capacitor produced using the barium titanate ceramic powder of this invention.

  Examples of the present invention will be described below to describe the features of the present invention in more detail.

<Example 1>
(1) Etching of BaTiO ₃ particles First, BaTiO ₃ powder having an average particle diameter of 0.30 μm was prepared. Then, 300 g of this BaTiO ₃ powder was weighed, put into 1 L of 0.2N dilute hydrochloric acid prepared separately, and stirred at room temperature for 60 minutes using a blade made of fluororesin (Teflon (registered trademark)). . Thereby, barium (Ba) constituting the A site in the case where BaTiO ₃ is expressed by the general formula ABO ₃ is dissolved to form Ti-rich BaTiO ₃ constituting the B site.

Thereafter, suction filtration was performed to remove the eluted Ba ²⁺ ions. Then, after the obtained solid content was sufficiently dispersed in 1 L of pure water (cleaning liquid), the cleaning liquid was filtered off. After this washing was repeated 5 times, the solid content was separated.

The separated solid (washed solid) was dried at 140 ° C. for a sufficient period of time, and then sized. The Ba / Ti ratio (molar ratio) of the BaTiO ₃ powder after etching thus obtained was 0.990.

(2) Addition of minor components and reaction on the surface of BaTiO ₃ particles Next, 300 g of pure water was added to 50 g of BaTiO ₃ powder after etching with acid to form a slurry, and the slurry was stirred at 70 ° C. Heated.

Separately, 0.160 g of Ca (OH) ₂ powder, which is an auxiliary component material, is weighed, added to the heated slurry, and further stirred at 70 ° C. for 1 hour, whereby the auxiliary component is BaTiO _3. The particles were reacted.

Thereafter, water was evaporated and removed in an oven set at 150 ° C., and then sized to obtain a barium titanate ceramic powder in which the surface layer of BaTiO ₃ particles was modified.

Incidentally, FIG. 1 is a method of manufacturing a barium titanate-based ceramic powder according to Example 1, after etching by acid BaTiO ₃ particles, solid-liquid reacting the secondary components on the surface of the etched BaTiO ₃ particles, forming a BaTiO ₃ particles was modified surface layer is a diagram schematically illustrating.

As shown in FIG. 1, in Example 1, the BaTiO ₃ particles 1a as a raw material is etched, and a Ti rich BaTiO ₃ particles 1b, adding pure water to the BaTiO ₃ particles 1b of the Ti-rich slurry By adding Ca (OH) ₂ powder, which is a subcomponent raw material, to this slurry and dissolving it, heating and stirring are continued to cause the subcomponent to undergo solid-liquid reaction on the surface of the BaTiO ₃ particles 1b. The reaction proceeds uniformly from every part of the natural surface of the BaTiO ₃ particles 1b. As a result, the BaTiO ₃ particles 1 whose surface layer has been modified in which the subcomponents have reacted uniformly on the surface are obtained. Note that the surface layer 2 of the BaTiO ₃ particles 1 having a core-shell structure is (Ba, Ca) TiO _{3 as} shown in FIG.

This barium titanate-based ceramic powder is represented by (Ba, Ca) TiO ₃ , the ratio (molar ratio) of (Ba + Ca) to Ti is (Ba + Ca) /Ti=1.000, and Ca and Ti This is a barium titanate-based ceramic powder having a ratio (molar ratio) of Ca / Ti = 0.01.

(3) Production of dielectric powder With respect to 100 mol parts of the modified powder (barium titanate ceramic powder) whose surface layer obtained in the step (2) was modified,
1.0 mol part of Dy ₂ O ₃ powder,
1.2 mol parts of MgCO ₃ powder,
0.2 mol part of MnCO ₃ powder,
_{1.0 mole part of} BaCO _{3 powder,}
A dielectric powder was prepared by adding 1.2 mol parts of SiO ₂ powder and grinding and mixing with a ball mill using pure water and 1 mmφ ZrO ₂ balls.

(4) Production of Multilayer Ceramic Capacitor A polybutyral binder and a plasticizer were added to the dielectric powder produced in the step (3) above, and toluene and ethyl alcohol were further added to form a slurry using a ball mill. And this slurry was shape | molded in the sheet form, and it produced in the ceramic green sheet which the thickness after sintering becomes 3.0 micrometers.

  And on this ceramic green sheet, the conductive paste which has nickel as a main component was screen-printed, and the conductive paste pattern (internal electrode pattern) used as an internal electrode after baking was formed. Thereafter, 11 ceramic green sheets on which conductive paste patterns are formed are stacked in such a manner that the conductive paste patterns are alternately drawn to the opposite side (so that the effective dielectric layer (capacitor forming layer) becomes 10 layers). Furthermore, a laminated block was produced by laminating ceramic green sheets on which the conductive paste pattern was not formed on the upper and lower surfaces as an outer layer.

Then, this laminated block was cut so that the size after sintering and densification was 3.2 mm in length and 1.6 mm in width to obtain a green laminated chip.
And this green laminated chip was heat-processed in air | atmosphere at 280 degreeC, and the binder was burned and removed. Subsequently, firing was performed in a N ₂ —H ₂ —H ₂ O stream at 1300 ° C. and oxygen partial pressure: 10 ^−9.7 MPa for 2 hours to obtain a fired laminated chip (laminated ceramic element).

  Then, a conductive paste mainly composed of copper was applied to both end faces of the fired laminated chip from which the internal electrodes were drawn, and baked at 800 ° C. to form external electrodes. Thereby, as schematically shown in FIG. 2, the internal electrode 12 disposed inside the multilayer ceramic element (ceramic sintered body) 10 is laminated via the ceramic layer 11 which is a dielectric layer, and Thus, a multilayer ceramic capacitor having a structure in which a pair of external electrodes 13a and 13b are provided on both end faces of the multilayer ceramic element 10 so as to be electrically connected to the internal electrodes 12 exposed on the opposite end face alternately.

<Example 2>
(a) Using 0.6N dilute hydrochloric acid for etching,
(b) The etching time was 45 minutes,
(c) Sr (OH) ₂ .8H ₂ O crystal was added as a subcomponent added to the BaTiO ₃ powder after etching at a ratio shown in Table 1, that is, to 50 g of the BaTiO ₃ powder after etching. Add 300 g of pure water to make a slurry, heat to 70 ° C. with stirring, add Sr (OH) ₂ .8H ₂ O crystal (1.154 g) to the heated slurry, and stir at 70 ° C. for 1 hour. A multilayer ceramic capacitor was fabricated by the same method and conditions as in the above <Example 1> except that the above was continued.

In Example 2, the Ba / Ti ratio (molar ratio) of the BaTiO ₃ powder after etching with acid was 0.980. And the said auxiliary component was added in the ratio used as the number of moles corresponded to the number of moles of Ba which eluted.

<Example 3>
(a) Addition of Ca (OH) ₂ powder and MgCO ₃ powder as subcomponents added to the BaTiO ₃ powder after etching in the proportions shown in Table 1, that is, BaTiO ₃ powder after etching Add 50 g of pure water to 50 g to make a slurry, heat to 70 ° C. with stirring, add Ca (OH) ₂ powder (0.159 g) and MgCO ₃ powder (0.001 g) to the heated slurry, Furthermore, a multilayer ceramic capacitor was produced by the same method and conditions as in the above <Example 1> except that stirring was continued at 70 ° C. for 1 hour.

In Example 3, the Ba / Ti ratio (molar ratio) of the BaTiO ₃ powder after etching with acid was 0.990. And the said auxiliary component was added in the ratio used as the number of moles corresponded to the number of moles of Ba which eluted.

<Example 4>
(a) Using 0.6N dilute hydrochloric acid for etching,
(b) The etching time was 120 minutes,
(c) As accessory components added to the BaTiO ₃ powder after etching, Ba (OH) ₂ .8H ₂ O crystals and Ca (OH) ₂ powder were added in the proportions shown in Table 1, that is, Then, 300 g of pure water was added to 50 g of the etched BaTiO ₃ powder to make a slurry, which was then heated to 70 ° C. with stirring. In addition, Ba (OH) ₂ .8H ₂ O crystals (2.426 g) and Ca ( OH) ₂ powder (0.081 g) was added, and a monolithic ceramic capacitor was produced by the same method and conditions as in the above <Example 1> except that stirring was continued at 70 ° C. for 1 hour.

In Example 4, the Ba / Ti ratio (molar ratio) of the BaTiO ₃ powder after etching with acid was 0.960. And the said auxiliary component was added in the ratio used as the number of moles corresponded to the number of moles of Ba which eluted.

<Example 5>
(a) using (Ba _0.95 Ca _0.05 ) TiO ₃ as the original BaTiO ₃ powder to be etched;
(b) 0.6N dilute hydrochloric acid was used for etching,
(c) The etching time was 45 minutes,
(d) Ba (OH) ₂ .8H ₂ O crystals and MgCO ₃ powder (0.009 g) were added in the proportions shown in Table 1 as subcomponents added to the etched BaTiO ₃ powder. That is, 300 g of pure water is added to 50 g of the etched BaTiO ₃ powder to form a slurry, which is heated to 70 ° C. with stirring, and Ba (OH) ₂ .8H ₂ O crystals (1.395 g) are added to the heated slurry. A multilayer ceramic capacitor was produced by the same method and conditions as in the above <Example 1> except that MgCO ₃ powder (0.009 g) was added and stirring was further continued at 70 ° C. for 1 hour.

In Example 5, the Ba / Ti ratio (molar ratio) of the BaTiO ₃ powder after acid etching was 0.980. And the said auxiliary component was added in the ratio used as the number of moles corresponded to the number of moles of Ba which eluted.

<Comparative Example 1>
Etching with acid was performed, and CaCO ₃ as a subcomponent was added so that (Ba + Ca) /Ti=1.000 and Ca / Ti = 0.01, but CaCO ₃ simply adhered to the surface of BaTiO ₃ particles. As in the case of Example 1, the subcomponent was used as a raw material powder without reacting with the BaTiO ₃ particles. In other respects, a multilayer ceramic capacitor was produced by the same method and conditions as in the above <Example 1>.

In Comparative Example 1, the Ba / Ti ratio (molar ratio) of the BaTiO ₃ powder after etching with acid was 0.960. And the said auxiliary component was added in the ratio used as the number of moles corresponded to the number of moles of Ba which eluted.

<Comparative example 2>
Lamination was carried out under the same method and conditions as in the above <Example 1>, except that BaTiO ₃ powder that was not etched with acid and that was not modified with the addition of subcomponents was used as a raw material powder. A ceramic capacitor was produced.
In Table 1, the production conditions and subcomponents of each sample of <Example 1> to <Example 5>, <Comparative Example 1>, and <Comparative Example 2> produced as described above were reacted. The presence / absence of a later unreacted heterogeneous phase is collectively shown.

[Evaluation of characteristics]
For each of the 50 laminated ceramic capacitors (samples) of <Example 1> to <Example 5>, <Comparative Example 1>, and <Comparative Example 2> manufactured as described above, the capacitance was 1 kHz and 1 Vrm. Under the conditions, the dielectric constant was measured with an LCR meter, and the relative dielectric constant was calculated from the obtained capacitance value.

Moreover, the temperature characteristic of the electrostatic capacitance in −55 ° C. to + 125 ° C. was measured for any 10 of the 50 samples. Then, since the capacitance change rate at 125 ° C. was the largest when the capacitance (C ₂₅ ) at + 25 ° C. was used as a reference, this was recorded as ΔC ₁₂₅ (%). ΔC ₁₂₅ (%) is a value obtained from the following equation (1).
ΔC ₁₂₅ (%) = {(C ₁₂₅ −C ₂₅ ) / C ₂₅ } × 100) (1)

Apart from these, 50 multilayer ceramic capacitors were set in a two-terminal jig connected in parallel, and a life test of insulation resistance was performed under the conditions of 175 ° C. and 40V.
The time required for the insulation resistance of the multilayer ceramic capacitor to drop to 1 MΩ was defined as the failure life in the life test.
Then, Weibull analysis was performed on the failure life obtained from the life test, and the average life (MTTF) was obtained.

The produced multilayer ceramic capacitor was polished with diamond slurry to expose the capacitor forming portion (the portion functioning as a dielectric layer). The Dy distribution is analyzed by wavelength dispersion X-ray spectroscopy with a 25 μm field of view, and the maximum count / average count ratio is calculated from the average count and maximum count of the characteristic X-rays (L-rays) detected. Calculated.
Table 2 shows the characteristics of the multilayer ceramic capacitors (samples) of <Example 1> to <Example 5>, <Comparative Example 1>, and <Comparative Example 2> examined as described above.

As shown in Table 2, in the case of the samples of Examples 1 to 5, the capacitance change rate ΔC ₁₂₅ was −12.3% (Example 1) to −13. As small as 8% (Example 2), the capacitance change rate (ΔC ₁₂₅ ) in the temperature range of −55 ° C. to + 125 ° C. is within ± 15% based on the X7R characteristic of EIA standard, that is, the capacitance of 25 ° C. It was confirmed that the characteristics were satisfied with a margin.

  Moreover, it was confirmed that MTTF was also long as 311 hours (Example 2) to 395 hours (Example 5).

In addition, the maximum / average count number ratio of the characteristic X-rays of Dy is as small as 1.5 (Examples 1, 4, 5) to 1.7 (Example 3), confirming that uniform porcelain is obtained It was done.
These effects are due to the homogeneous modification of the surface layer of the BaTiO ₃ particles as described above.

On the other hand, in the case of Comparative Example 1 in which the etching of the BaTiO ₃ particles was performed but the step of reacting the added subcomponent with the BaTiO ₃ particles was not performed, the relative dielectric constant was less than 3000 and the EIA standard X7R characteristic was not satisfied. It was confirmed.

Furthermore, in Comparative Example 1, the capacity change rate ([Delta] C ₁₂₅₎ is large and -15.1%, also, MTTF also 80 hours (Comparative Example 1) and short, it was found that undesirable.

  Furthermore, in the case of the comparative example 1, the maximum / average count number ratio of the characteristic X-rays of Dy was as large as 4.2, and it was confirmed that the porcelain was low in uniformity.

Further, in the case of Comparative Example 2 in which the BaTiO ₃ particles are not etched and the surface layer is not modified by the addition of subcomponents, the relative permittivity satisfies 3030 and the X7R characteristic of the EIA standard, but the capacitance change rate ( ΔC ₁₂₅ ) was as large as −14.8%, which was not preferable.

Furthermore, in the case of Comparative Example 2, the MTTF was as short as 210 hours, and the maximum / average count number ratio of Dy characteristic X-rays was as large as 2.8, confirming that the ceramic was heterogeneous. . This is because, in the case of barium titanate-based ceramic powder of Comparative Example 2, since the sub-component is only attached to the BaTiO ₃ particles, the surface of the BaTiO ₃ particles, are reacted with secondary components and the BaTiO ₃ particles, This is thought to be due to the heterogeneous progression.

  The barium titanate-based ceramic powder produced by the method of the present invention can be applied not only to multilayer ceramic capacitors but also to LC composite parts.

  The present invention is not limited to the above examples in other respects as well, and the type of each raw material, the heating rate in the calcination step, and the auxiliary of Ba in the production of the barium titanate ceramic powder of the present invention. Various substitutions and modifications can be added within the scope of the invention with respect to the ratio of substitution by components.

1a before etching BaTiO ₃ particles 1b after etching of Ti-rich BaTiO ₃ BaTiO ₃ and the particles 1 surface modified particles 2 BaTiO ₃ particles in the surface layer 11 ceramic layers 12 internal electrode layers 13a, 13b external electrode 10 laminated ceramic device

Claims (3)

By etching the (a) BaTiO ₃ particles, eluting the BaTiO ₃ particles surface Ba, the etching process for the Ti excess BaTiO ₃ particles,
(b) a compound addition step of adding at least one compound selected from the group consisting of Ca, Sr, and Mg to the Ti-rich BaTiO ₃ particles;
(c) A method for producing a barium titanate-based ceramic powder, comprising: reacting the compound added in the step (b) with the Ti-excess BaTiO ₃ particles. The compound addition step of (b), the in BaTiO ₃ particle dispersion of BaTiO ₃ particles etched dispersed in an aqueous dispersion medium in the step of (a), Ca, Sr, and at least selected from the group consisting of Mg A step of dissolving one kind of compound, and the reaction step (c) is a solution in which at least one compound selected from the group consisting of Ca, Sr and Mg is dissolved in the BaTiO ₃ particle dispersion at room temperature. The method for producing a barium titanate-based ceramic powder according to claim 1, wherein the compound is reacted with the Ti-excess BaTiO ₃ particles by stirring at a temperature exceeding room temperature. On the surface of the Ti excess BaTiO ₃ particles, Ca, Sr, and at least one compound selected from the group consisting of Mg is, in a ratio such that the number of moles corresponding to the excess number of moles of Ti of at least the BaTiO ₃ particles The barium titanate-based ceramic powder is held in a state of reacting with the surface of the BaTiO ₃ particles.

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