KR20220035115A - Me element substituted organic acid barium titanyl, method for producing same, and method for producing titanium-based perovskite-type ceramic raw material powder - Google Patents

Abstract

Me element-substituted organic acid barium titanyl in which a part of the Ba site is substituted with a Me element (Me represents at least one selected from Ca, Sr and Mg), the molar ratio of the sum of Ba and Me elements to Ti ((Ba+Me)/Ti) is 0.980 or more and less than 0.999, and the molar ratio of Me to Ba (Me/Ba) is 0.001 or more and 0.250 or less, Me element-substituted organic acid barium titanyl powder.

Description

Me element substituted organic acid barium titanyl, method for producing same, and method for producing titanium-based perovskite-type ceramic raw material powder

The present invention relates to an organic acid barium titanyl in which a part of the barium element useful as a raw material for functional ceramics such as dielectrics, piezoelectric materials, optoelectronic materials, semiconductors, and sensors is substituted with other elements, and a method for producing the same.

The dielectric layer of a multilayer ceramic chip capacitor (MLCC) generally takes the form of a multi-component system composed of barium titanate as a main raw material and a trace amount of additives. For example, calcium is a component often used as an additive, but by substitutional solid solution in barium sites in barium titanate, it is effective as a depressor to smooth the temperature characteristics of dielectric constant, or as a component of glass serving as a sintering aid. What is used is known.

Barium titanate having the above-described multi-component system is obtained by adding minor components using conventionally known solid phase method, oxalate method, hydrothermal synthesis method, alkoxide method, and the like. Among them, the oxalate method is a method for synthesizing barium titanate by heat-treating a wet-synthesized oxalate precursor and deoxalic acid. And the greatest characteristic of the oxalate method is that high-quality and stoichiometric barium titanate is obtained from the composition ratio (Ba/Ti) of barium and titanium in the precursor crystal.

Although several processes have been reported for the oxalate method, industrially, a method in which a mixture of titanium chloride and barium chloride is added to an aqueous oxalic acid solution to perform the reaction is common. A method for producing barium titanyl oxalate in which a part of barium element is substituted with another metal element using this oxalate method has been proposed.

For example, Patent Document 1 describes a method in which a mixed solution of titanium chloride and barium chloride contains another alkaline earth metal compound to be substituted, and this is added to an aqueous oxalic acid solution. However, since it is difficult for the reaction to proceed quantitatively, there is a disadvantage that is not industrially advantageous.

So, in order to progress the reaction quantitatively, in Patent Document 2, when a solution containing titanium tetrachloride and oxalic acid is added to a solution containing a barium compound and a compound containing another element to be substituted, the reaction is performed, the reactivity is improved, , that barium titanyl oxalate having a high substitution ratio of barium and other elements to be substituted is obtained.

In Patent Document 3, an alkaline earth metal such as barium and calcium and It is described that a fine powder of a ceramic raw material having good dispersibility of titanium and excellent uniformity is obtained.

Japanese Patent Laid-Open No. 2003-212543 Japanese Patent Laid-Open No. 2006-188469 Japanese Patent Laid-Open No. 4-292455

However, in the method described in Cited Document 2, other elements such as calcium can be substituted for barium sites with high probability, but since the reactivity is too high, it is difficult to uniformly distribute the substituted elements throughout the barium titanyl oxalate. there was.

In addition, according to the Example of Cited Document 3, it is described that a product having a composition according to the input composition is obtained, but there is no evaluation regarding uniformity, and there is a case where pH adjustment is performed using ammonia, so it is an industrially advantageous method. can't

Accordingly, it is an object of the present invention to provide organic acid barium titanyl and barium titanate in which a part of the Ba site is substituted with another element (Me element), the substituted element is not segregated, and the whole organic acid barium titanyl powder or barium titanate powder To provide a Me element-substituted organic acid barium titanyl powder and barium titanate powder uniformly distributed throughout, and to provide a method for industrially advantageously manufacturing the organic acid barium titanyl or the corresponding barium titanate powder there is.

As a result of repeated intensive research in view of the above circumstances, the present inventors set the molar ratio of the sum of Ba and Me elements to Ti of the organic acid barium titanyl to be 0.980 to 0.999, which is a range slightly smaller than 1, and also to the Me element to Ba. By setting the molar ratio of 0.001 to 0.200, it was found that an organic acid barium titanyl powder with little segregation was obtained, and the present invention was completed.

That is, the present invention (1) provides an organic acid barium titanyl substituted with a Me element, wherein a part of the Ba site is substituted with a Me element (Me represents at least one selected from Ca, Sr and Mg),

The molar ratio of the sum of Ba and Me elements to Ti ((Ba+Me)/Ti) is 0.980 or more and less than 0.999, and the molar ratio of Me to Ba (Me/Ba) is 0.001 or more and 0.250 or less

It is to provide a Me element-substituted organic acid barium titanyl powder, characterized in that.

Further, in the present invention (2), in the electron probe microanalyzer (EPMA) analysis, the Me element is uniformly contained in the particles of the Me element-substituted barium titanate powder obtained by calcining the Me element-substituted organic acid barium titanyl powder. To provide an organic acid barium titanyl powder substituted with the Me element of (1), characterized in that it is distributed.

Further, according to the present invention (3), the surface image of the green compact of Me element-substituted barium titanate obtained by calcining the Me element-substituted organic acid barium titanyl powder is one variation using electron probe microanalyzer (EPMA) analysis. In the image analysis obtained by mapping analysis of 256 vertical and horizontal points at 0.8 μm intervals so as to have a square range of 205 μm, the CV value (standard deviation/average value) of Ca is 0.4 or less, Me element-substituted organic acid of (1) To provide barium titanyl powder.

Further, in the present invention (4), an aqueous solution obtained by mixing a barium compound, an elemental Me compound, and a titanium compound with water (solution A) is added to an aqueous organic acid solution (solution B) to obtain Me element-substituted organic acid barium titanyl A method for producing an element-substituted organic acid barium titanyl powder, the method comprising:

In the liquid A, the molar ratio (Me/Ba) of the element Me to Ba is 0.020 or more and 5.000 or less, the molar ratio of Ba to Ti (Ba/Ti) is 0.300 or more and 1.200 or less, and the solution A and The mixing temperature of solution B is 10 to 50 ° C.

It is to provide a method for producing a Me element-substituted organic acid barium titanyl powder, characterized in that.

In addition, the present invention (5) provides a method for producing barium titanyl powder with Me element substituted organic acid according to (4), wherein the barium compound is at least one selected from the group consisting of barium chloride, barium carbonate and barium hydroxide. will provide

Further, in the present invention (6), the Me of (4) or (5), wherein the element Me compound is at least one member selected from the group consisting of a chloride of an element of Me, a carbonate of an element of Me and a hydroxide of an element of Me To provide a method for producing an element-substituted organic acid barium titanyl powder.

Further, the present invention (7) provides a method for producing the Me element-substituted organic acid barium titanyl powder according to any one of (4) to (6), wherein the titanium compound is at least one selected from titanium tetrachloride and titanium lactate. will provide

Further, in the present invention (8), the Me element-substituted organic acid barium titanyl according to any one of (4) to (7), wherein the organic acid is at least one selected from the group consisting of oxalic acid, citric acid, malonic acid and succinic acid. To provide a method for preparing a powder.

Further, the present invention (9) is a titanium-based perovskite ceramic characterized in that barium titanate substituted with a Me element is obtained by calcining the Me element-substituted barium titanyl powder according to any one of (1) to (3). To provide a method for producing a raw material powder.

Further, the present invention (10) is, by calcining the Me element substituted organic acid barium titanyl powder obtained by performing the production method of the Me element substituted organic acid barium titanyl powder according to any one of (4) to (8), whereby Me element substituted titanyl acid To provide a method for producing a titanium-based perovskite-type ceramic raw material powder, characterized in that the barium powder is obtained.

According to the present invention, the organic acid barium titanyl and barium titanate in which a part of the Ba site is substituted with another element (Me element), the substituted element is not segregated, and the whole organic acid barium titanyl powder or the whole barium titanate powder It is possible to provide a Me element-substituted organic acid barium titanyl powder and a barium titanate powder uniformly distributed, and a method for industrially advantageously manufacturing the organic acid barium titanyl or barium titanate powder.

1 is a result of mapping analysis of Ca atoms by EPMA of barium calcium titanate powder obtained in Example 1. FIG.
2 is an XRD analysis result of barium calcium titanyl oxalate obtained in Examples 1 to 5 and Comparative Examples 1 to 2;
3 is a result of mapping analysis of Ca atoms by EPMA of barium calcium titanate powder obtained in Example 2. FIG.
4 is a result of mapping analysis of Ca atoms by EPMA of barium calcium titanate powder obtained in Example 3. FIG.
FIG. 5 is a result of mapping analysis of Ca atoms by EPMA of barium calcium titanate powder obtained in Example 4. FIG.
6 is a result of mapping analysis of Ca atoms by EPMA of barium calcium titanate powder obtained in Example 5;
7 is a result of mapping analysis of Ca atoms by EPMA of barium calcium titanate powder obtained in Comparative Example 1. FIG.
FIG. 8 is a result of mapping analysis of Ca atoms by EPMA of barium calcium titanate powder obtained in Comparative Example 2. FIG.

In the Me element-substituted organic acid barium titanyl powder of the present invention, a portion of Ba sites are substituted with Me element (Me represents at least one selected from Ca, Sr, and Mg). ego,

The molar ratio of the sum of Ba and Me elements to Ti ((Ba+Me)/Ti) is 0.980 or more and less than 0.999, and the molar ratio of Me to Ba (Me/Ba) is 0.001 or more and 0.250 or less

It is a Me element-substituted organic acid barium titanyl powder characterized by

The Me element-substituted organic acid barium titanyl powder of the present invention is a powder, and is an aggregate of particles of organic acid barium titanyl in which a part of Ba sites are substituted with Me elements.

In the Me element-substituted organic acid barium titanyl powder of the present invention, the Me element substituted for a part of the Ba sites of the organic acid barium titanyl is at least one element selected from Ca, Sr and Mg, preferably Ca, Sr, particularly preferably Ca. One type may be sufficient as Me, and 2 or more types may be sufficient as it.

In the Me element-substituted organic acid barium titanyl powder of the present invention, the organic acid is at least one selected from the group consisting of oxalic acid, citric acid, malonic acid and succinic acid, preferably oxalic acid and citric acid, and particularly preferably oxalic acid.

The molar ratio ((Ba+Me)/Ti) of the sum of Ba and Me elements to Ti in the Me element-substituted organic acid barium titanyl powder of the present invention is 0.980 or more and less than 0.999, preferably 0.983 or more and 0.998 or less, particularly preferably is 0.985 or more and 0.997 or less. When (Ba+Me)/Ti is in the above range, a Me element substituted organic acid barium titanyl powder with less segregation of Me element in which Me element is uniformly distributed throughout the powder is obtained, and further, by calcination, Me A Me element-substituted barium titanate powder in which the elements are uniformly distributed throughout the powder and the segregation of the Me element is small is obtained. On the other hand, when (Ba+Me)/Ti is less than the above range, it is difficult to obtain Me element-substituted barium titanate having desired characteristics, and when (Ba+Me)/Ti is less than the above range, segregation of the Me element tends to occur when it exceeds the above range.

The molar ratio (Me/Ba) of the element Me to Ba in the Me element-substituted organic acid barium titanyl powder of the present invention is 0.001 or more and 0.250 or less, preferably 0.005 or more and 0.150 or less. When Me/Ba is in the above range, Me element is uniformly distributed throughout the powder, Me element substituted organic acid barium titanyl with less segregation of Me element is obtained, and further, by calcination, Me element is distributed throughout the particles. A Me element-substituted barium titanate having uniform distribution and less segregation of Me element is obtained. On the other hand, when Me/Ba is less than the above range, it is difficult to obtain Me element-substituted barium titanate having desired properties, and when Me/Ba is more than the above range, segregation of Me element tends to occur.

In the Me element-substituted organic acid barium titanyl powder of the present invention, the organic acid is oxalic acid, for example, the following general formula (1):

(Ba _1-p Me _p ) _q TiO(C ₂ O ₄ ) ₂ nH ₂ O (1)

(Wherein, Me represents at least one element selected from Ca, Sr and Mg, p is 0.001≤p≤0.200, q is 0.980≤q<0.999, and n is an integer from 1 to 8).

and Me element-substituted barium titanyl oxalate powder represented by .

In general formula (1), Me is at least 1 sort(s) of element chosen from Ca, Sr, and Mg, Preferably it is Ca and Sr, Especially preferably, it is Ca. One type may be sufficient as Me, and 2 or more types may be sufficient as it. That is, in the Me element-substituted barium titanyl oxalate powder represented by general formula (1), a part of Ba site is substituted by 1 type(s) or 2 or more types selected from Ca, Sr, and Mg.

In General Formula (1), the value of q corresponds to the molar ratio ((Ba+Me)/Ti) of the sum total of Ba and Me elements with respect to Ti in terms of atoms. q is 0.980 or more and less than 0.999, Preferably they are 0.983 or more and 0.998 or less, Especially preferably, they are 0.985 or more and 0.997 or less. When q is in the above range, the Me element is uniformly distributed throughout the powder, a Me element-substituted barium titanyl oxalate powder with little segregation of Me element is obtained, and the Me element is uniform throughout the powder by calcination. Me-element-substituted barium titanate powder with small segregation of Me element is obtained. On the other hand, when q is less than the above range, it is difficult to obtain Me element-substituted barium titanate having desired properties, and when q exceeds the above range, segregation of Me element tends to occur.

In General Formula (1), p corresponds to the molar ratio (Me/Ba) of the Me element to Ba in terms of atoms. p is 0.001 or more and 0.200 or less, Preferably it is 0.005 or more and 0.150 or less. When p is in the above range, the Me element is uniformly distributed throughout the powder, Me element-substituted barium titanyl oxalate with little segregation of Me element is obtained, and further, the Me element is uniformly distributed throughout the particles by firing and Me element-substituted barium titanate with little segregation of Me element is obtained. On the other hand, when p is less than the above range, it is difficult to obtain Me element-substituted barium titanate having desired properties, and when p is more than the above range, segregation of Me element tends to occur.

In general formula (1), n is an integer of 1-8. As for n, the integer of 3-7 is preferable.

In addition, about the molar ratio of each atom of Ti, Ba, and Me in Me element-substituted barium titanyl oxalate represented by General formula (1), based on the measurement value of a fluorescent X-ray analyzer (Rigaku Co., Ltd. product, ZSX100e) can be calculated by In addition, about the molar ratio of each atom of Ti, Ba, and Me in Me element-substituted barium titanyl oxalate represented by General formula (1), Me element-substituted barium titanate obtained by calcining Me element-substituted barium titanyl oxalate is fluorescent. It can also be calculated based on the value obtained by measuring with an X-ray analyzer (made by Rigaku Co., Ltd., ZSX100e).

The average particle diameter of the Me element-substituted organic acid barium titanyl powder of the present invention is not particularly limited, but is preferably 0.1 to 300 µm, particularly preferably 0.5 to 200 µm. In addition, in this invention, the average particle diameter of Me element-substituted organic acid barium titanyl refers to the particle diameter (D50) of 50% of the volume integration in the particle size distribution calculated|required by the laser diffraction and scattering method.

The calcined product obtained by calcining the Me element-substituted organic acid barium titanyl powder of the present invention at 600 to 1200 ° C., preferably 650 to 1100 ° C. barium titanate. That is, the calcined product of the Me element-substituted organic acid barium titanyl powder of the present invention has the following general formula (2):

(Ba _1-x Me _x ) _y TiO ₃ (2)

Me element-substituted barium titanate powder represented by . In general formula (2), Me is at least 1 sort(s) chosen from Ca, Sr, and Mg. x is 0.001≤x≤0.200, preferably 0.010≤x≤0.150. Further, y is 0.980≤y<0.999, preferably 0.983≤y≤0.998, particularly preferably 0.985≤y≤0.997.

In the Me element-substituted barium titanate powder obtained by calcining the Me element-substituted organic acid barium titanyl powder of the present invention at 600 to 1200°C, preferably 650 to 1100°C, the Me element in each particle is uniformly distributed in the particles, there is. Further, in the present invention, the uniform distribution of the Me element in the particles of the Me element-substituted barium titanate is determined by using an electron probe microanalyzer (EPMA) analysis on the surface of the Me element-substituted barium titanate green compact. In the image analysis obtained by performing mapping analysis of 256 vertical and horizontal points at 0.8 μm intervals so as to have a square range with a side of 205 μm, the CV value (standard deviation/average value) of Ca is calculated, and this value indicates that it is 0.4 or less .

The method for producing the Me element-substituted organic acid barium titanyl powder of the present invention is obtained by mixing a barium compound, a Me element compound (Me represents at least one selected from Ca, Sr and Mg) and a titanium compound in water. It is a manufacturing method of Me element-substituted organic acid barium titanyl powder which obtains Me element-substituted organic acid barium titanyl by adding an aqueous solution (A solution) to an organic acid aqueous solution (B solution),

In the liquid A, the molar ratio (Me/Ba) of the element Me to Ba is 0.020 or more and 5.000 or less, the molar ratio of Ba to Ti in terms of atomic conversion (Ba/Ti) is 0.300 or more and 1.200 or less, and Addition rate of solution A to solution B is 2.0 ml/min or more

It is a method for producing a Me element-substituted organic acid barium titanyl powder, characterized in that.

In the method for producing the Me element-substituted organic acid barium titanyl powder of the present invention, first, the entire amount of solution B used for the reaction is put in a reaction vessel, then solution A is supplied to the reaction vessel, and solution A is added to solution B. , A method for producing an organic acid barium titanyl substituted with a Me element by performing a reaction to produce an organic acid barium titanyl substituted with an element Me.

Solution A according to the method for producing barium titanyl, an organic acid substituted with an element of Me, of the present invention is an aqueous solution obtained by mixing a barium compound, an elemental Me compound, and a titanium compound with water.

The barium compound related to the method for producing the organic acid barium titanyl substituted with the element Me of the present invention is not particularly limited, and examples include barium chloride, barium carbonate, barium hydroxide, barium acetate, and barium nitrate. The number of barium compounds may be one, and 2 or more types of combined use may be sufficient as them. As a barium compound, the 1 type(s) or 2 or more types selected from the group which consists of barium chloride, barium carbonate, and barium hydroxide are preferable.

The Me element compound for the method for producing the Me element-substituted organic acid barium titanyl of the present invention is not particularly limited, and chlorides, hydroxides and carbonates containing one or two or more elements selected from the group consisting of Ca, Sr and Mg. , acetate, nitrate, and the like. The number of Me element compounds may be one, or 2 or more types of combined use may be sufficient as them. As the element Me compound, one or two or more selected from the group consisting of a chloride of an element Me, a carbonate of an element Me, and a hydroxide of an element Me is preferable.

The titanium compound related to the method for producing the organic acid barium titanyl substituted with Me element of the present invention is not particularly limited, and titanium tetrachloride, titanium lactate, and the like can be mentioned. The number of titanium compounds may be one, and 2 or more types of combined use may be sufficient as them. As the titanium compound, titanium tetrachloride is preferable.

Examples of the organic acid related to the method for producing the Me element-substituted organic acid barium titanyl of the present invention include oxalic acid, citric acid, malonic acid, and succinic acid. The number of organic acids may be one, and 2 or more types of combined use may be sufficient as them. As the organic acid, oxalic acid is preferable.

In the present invention, using barium chloride as the barium compound, using the chloride of the element Me as the element compound, using titanium tetrachloride as the titanium compound, and using oxalic acid as the organic acid, the reactivity is high and stable It is preferable at the point that a thing of quality is obtained with a high yield.

In liquid A, the molar ratio (Me/Ba) of the element Me to Ba in terms of atoms is 0.020 or more and 5.000 or less, and preferably 0.050 or more and 4.000 or less. When the molar ratio (Me/Ba) of the Me element to Ba in terms of atoms in the solution A is within the above range, the Me element is uniformly distributed throughout the powder, and Me element-substituted organic acid barium titanyl with little segregation of the Me element A powder is obtained and, by calcination, a Me element-substituted barium titanate powder in which the Me element is uniformly distributed throughout the powder and the segregation of the Me element is small is obtained. On the other hand, when the molar ratio (Ba/Ti) of Ba to Ti in terms of atoms in the liquid A is less than the above range, substitution of the Me element is difficult to proceed, and when it exceeds the above range, segregation of the Me element tends to occur.

In the liquid A, the molar ratio (Ba/Ti) of Ba to Ti in terms of atoms is 0.300 or more and 1.200 or less, and preferably 0.350 or more and 1.150 or less. When the molar ratio (Ba/Ti) of Ba to Ti in terms of atoms in the liquid A is within the above range, the Me element is uniformly distributed throughout the particles, and the Me element-substituted organic acid barium titanyl with little segregation of the Me element is obtained, and by calcination, Me element substituted barium titanate in which Me element is uniformly distributed over the whole particle and segregation of Me element is small is obtained. On the other hand, when the molar ratio (Ba/Ti) of Ba to Ti in terms of atoms in the liquid A is less than the above range, substitution of the Me element is difficult to proceed, and when it exceeds the above range, segregation of the Me element tends to occur.

The concentration of Ba in the liquid A is not particularly limited, but is preferably 0.05 to 1.00 mol/L, particularly preferably 0.10 to 0.90 mol/L, in terms of atoms.

The concentration of the Me element in the liquid A is not particularly limited, but is preferably 0.002 to 6.50 mol/L, particularly preferably 0.10 to 6.00 mol/L, in terms of atoms.

The Ti concentration in the liquid A is not particularly limited, but is preferably 0.05 to 1.35 mol/L, particularly preferably 0.10 to 1.30 mol/L, in terms of atoms.

Solution B according to the method for producing the element-substituted organic acid barium titanyl for Me of the present invention is an organic acid aqueous solution obtained by dissolving an organic acid in water.

The ratio of the total number of moles of Ba, Me elements and Ti in terms of atoms in the liquid A to the number of moles of the organic acid ions in the liquid B is 0.800 or more and 1.400 or less, preferably 0.850 or more and 1.300 or less, and particularly preferably 0.900 or more and 1.250 or less. When the ratio of the total number of moles of Ba, Me elements, and Ti in terms of atoms in the liquid A to the number of moles of organic acid ions in the liquid B is within the above range, the element Me is uniformly distributed throughout the particles, and segregation of the element Me is small. A Me element substituted organic acid barium titanyl is obtained.

The concentration of the organic acid ion in the liquid B is not particularly limited, but is preferably 0.10 to 5.00 mol/L, particularly preferably 0.50 to 3.00 mol/L.

In the method for producing barium titanyl, an organic acid substituted with Me element of the present invention, first, the entire amount of the B solution is put into the reaction vessel, then the A solution is supplied to the reaction vessel, and the A solution is added to the B solution, so that in the reaction vessel A reaction for producing barium titanyl, an organic acid substituted with Me element, is carried out.

The rate of addition of the solution A when adding the solution A to the solution B also varies depending on the scale to be carried out. By adding the liquid A to the liquid B at the said addition rate, the Me element-substituted organic acid barium titanyl in which the Me element is uniformly distributed throughout the particle|grains and segregation of Me element is little is obtained. In addition, as long as the said addition rate is satisfy|filled, an upper limit in particular is not restrict|limited.

The mixing temperature when adding the liquid A to the liquid B, that is, the temperature of the liquid A when adding the liquid A to the reaction vessel and the reaction liquid (or liquid B) in the reaction vessel is usually 10 to 50° C., preferably 15 to 45°C. By adding the liquid A to the liquid B at the above mixing temperature, barium titanyl, an organic acid substituted with a Me element, is obtained in which the element Me is uniformly distributed throughout the particles and the segregation of the element Me is small.

After adding the entire amount of solution A to solution B, the reaction may be terminated by immediately cooling the reaction solution or removing the reaction solution by filtration or the like, or after adding the entire amount of solution A to solution B, the reaction solution is You may perform aging which maintains at a predetermined temperature for a fixed period of time. In the case of aging, the aging temperature is preferably 10° C. or higher, particularly preferably 20 to 80° C., and the aging time is preferably 0.1 hour or longer, particularly preferably 0.2 hour or longer.

When the liquid A is being added to the liquid B, it is preferable to add the liquid A to the liquid B while stirring the reaction liquid (or liquid B). In addition, when aging is performed after adding the whole amount of liquid A to liquid B, it is preferable to perform aging while stirring the reaction solution. The stirring speed is not particularly limited, but from the start of the addition of the solution A to the solution B until the end of the addition of the entire amount of the solution A, or, in the case of aging, until the end of the aging, a reaction containing the produced Me element-substituted organic acid barium titanyl What is necessary is just a stirring speed which becomes a state in which a liquid always flows.

When aging is performed after adding the entire amount of liquid A to liquid B, solid-liquid separation of the reaction liquid is performed by a conventional method after aging is completed, and then the solid content is washed with water. Although it does not restrict|limit especially as a water washing method, Cleaning by repulping etc. is preferable at a point with high cleaning efficiency. After washing, the solid content is dried and, if necessary, pulverized to obtain an organic acid barium titanyl substituted with a Me element, that is, an organic acid barium titanyl in which a part of the Ba sites are substituted with an element Me.

In this way, the Me element-substituted organic acid barium titanyl powder obtained by performing the method for producing the Me element-substituted organic acid barium titanyl powder of the present invention is an organic acid barium titanyl in which a part of the Ba sites are substituted with Me elements, and Ti The molar ratio ((Ba+Me)/Ti) of the sum of Ba and Me elements to Ba is 0.980 or more and less than 0.999, and the molar ratio of Me to Ba (Me/Ba) is 0.001 or more and 0.250 or less.

In the Me element-substituted barium titanyl obtained by performing the method for producing the Me element-substituted organic acid barium titanyl powder of the present invention, the Me element represents at least one element selected from Ca, Sr and Mg, preferably Ca , Sr, particularly preferably Ca, the molar ratio of the sum of Ba and Me elements to Ti ((Ba+Me)/Ti) is 0.980 or more and less than 0.999, preferably 0.983 or more and 0.998 or less, particularly preferably 0.985 It is 0.997 or more, and the molar ratio of Me element to Ba (Me/Ba) is 0.001 or more and 0.250 or less, Preferably it is 0.005 or more and 0.150 or less.

The average particle diameter of the Me element substituted organic acid barium titanyl powder obtained by performing the method for producing the Me element substituted organic acid barium titanyl powder of the present invention is not particularly limited, but is preferably 0.1 to 300 µm, particularly preferably 0.5 to 200 µm am.

In the method for producing the Me element-substituted organic acid barium titanyl powder of the present invention, a Me element-substituted organic acid barium titanyl powder in which the Me element is uniformly distributed throughout the powder and the segregation of the Me element is small is obtained. In addition, Me element is uniformly distributed throughout the Me element-substituted organic acid barium titanyl powder, and the segregation of Me element is small, Me element-substituted organic acid obtained by performing the manufacturing method of Me element-substituted organic acid barium titanyl powder of the present invention It is confirmed by calcining the barium titanyl powder at 600 to 1200°C, and performing a mapping analysis of the Me element-substituted barium titanate obtained by EPMA.

Further, Me element substituted barium titanate obtained by calcining Me element substituted organic acid barium titanyl powder obtained by performing the method for producing Me element substituted organic acid barium titanyl powder of the present invention at 600 to 1200°C, preferably 650 to 1100°C In , the Me element is uniformly distributed on the particle surface. Moreover, in the Me element-substituted organic acid barium titanyl powder obtained by performing the manufacturing method of the Me element-substituted organic acid barium titanyl powder of this invention, Me element is distributed uniformly in the depth direction of particle|grains.

Me element substituted barium titanyl powder of the present invention, and Me element substituted barium titanate powder obtained by calcining Me element substituted organic acid barium titanyl powder obtained by performing the production method of Me element substituted organic acid barium titanyl powder of the present invention , is suitably used as a titanium-based perovskite-type ceramic raw material powder for dielectric ceramic materials. That is, the Me element-substituted organic acid barium titanyl powder of the present invention or the Me element-substituted organic acid barium titanyl powder obtained by performing the production method of the Me element-substituted organic acid barium titanyl powder of the present invention is heated to 600 to 1200°C, preferably 650°C. By calcining at 1100° C., it is possible to obtain a titanium-based perovskite type ceramic raw material powder.

Me element substituted barium titanyl powder of the present invention, and Me element substituted barium titanate powder obtained by calcining Me element substituted organic acid barium titanyl powder obtained by performing the production method of Me element substituted organic acid barium titanyl powder of the present invention , the general formula (2):

(Ba _1-x Me _x ) _y TiO ₃ (2)

Me element-substituted barium titanate powder represented by . In general formula (2), Me is at least 1 sort(s) chosen from Ca, Sr, and Mg. x is 0.001≤x≤0.200, preferably 0.005≤x≤0.150. Further, y is 0.980≤y<0.999, preferably 0.983≤y≤0.998, particularly preferably 0.985≤y≤0.997.

Before performing the above firing, if necessary, the average particle size of the organic acid barium titanyl substituted with the Me element is preferable so that a fine titanium-based perovskite type ceramic raw material powder with high crystallinity can be obtained even if the firing is performed in a low temperature region. You may wet-pulverize the Me element-substituted organic acid barium titanyl powder by a ball mill, a bead mill, etc. so that it may become 4 micrometers or less, especially preferably 0.02-0.5 micrometers. In this case, as the solvent used in the wet grinding treatment, one that is inert to the Me element-substituted organic acid barium titanyl is used, for example, water, methanol, ethanol, propanol, butanol, toluene, xylene, acetone, methylene chloride, and ethyl acetate. , dimethylformamide, diethyl ether, and the like. Among them, examples of the solvent for the wet grinding treatment include organic solvents such as methanol, ethanol, propanol, butanol, toluene, xylene, acetone, methylene chloride, ethyl acetate, dimethylformamide and diethyl ether, Ba element, Ti element and Me It is preferable that there is little elution of the element from the viewpoint of obtaining a titanium-based perovskite-type ceramic raw material powder with high crystallinity.

The manufacturing method of the titanium-based perovskite type ceramic raw material powder of the present invention is obtained by performing the manufacturing method of the Me element-substituted organic acid barium titanyl powder of the present invention or the Me element-substituted organic acid barium titanyl powder of the present invention. A method for producing a titanium-based perovskite type ceramic raw material powder, wherein the Me element-substituted barium titanate is obtained by calcining the organic acid barium titanyl powder.

Organic acid derived from organic acid contained in the Me element-substituted organic acid barium titanyl powder is not preferable because it impairs the dielectric properties of the material and causes unstable behavior in the thermal process for ceramization. Therefore, in the method for producing a titanium-based perovskite-type ceramic raw material powder of the present invention, by sintering the Me element-substituted organic acid barium titanyl powder, the organic acid barium titanyl containing the Me element is thermally decomposed to obtain the target titanium-based perovskite-type ceramic While obtaining Me element-substituted barium titanate which is a raw material powder, the organic substance derived from an organic acid is removed.

In the method for producing the titanium-based perovskite type ceramic raw material powder of the present invention, the firing temperature at the time of firing is 600 to 1200°C, preferably 650 to 1100°C. When the calcination temperature is less than the above range, it is difficult to obtain a single-phase titanium-based perovskite type ceramic powder, and when the firing temperature is higher than the above range, the fluctuation of the particle size becomes large. In the method for producing the titanium-based perovskite-type ceramic raw material powder of the present invention, the firing time at the time of firing is preferably 0.2 to 30 hours, particularly preferably 0.5 to 20 hours. In the method for producing the titanium-based perovskite-type ceramic raw material powder of the present invention, the firing atmosphere at the time of firing is not particularly limited, and either an atmospheric atmosphere or an inert gas atmosphere may be used.

In the method for producing the titanium-based perovskite-type ceramic raw material powder of the present invention, firing may be performed only once, or may be repeated twice or more if necessary. In the case of repeating the firing, in order to make the powder properties uniform, the fired product may be pulverized and then the next firing may be performed.

In the method for producing the titanium-based perovskite-type ceramic raw material powder of the present invention, it is cooled appropriately after firing and, if necessary, pulverized to form a titanium-based perovskite-type composite oxide, suitable as a titanium-based perovskite-type ceramic raw material powder Me element-substituted barium titanate powder is obtained. In addition, the grinding|pulverization performed as needed is suitably performed when the Me element-substituted barium titanate powder obtained by baking is a weakly bonded block-like thing, etc., The particle itself of Me element-substituted barium titanate powder itself has a specific average particle diameter, BET ratio. it has a surface area. That is, the Me element-substituted barium titanate powder obtained by performing the method for producing the titanium-based perovskite-type ceramic raw material powder of the present invention has an average particle diameter determined by scanning electron microscopy (SEM) of 0.01 to 4 µm, preferably is 0.02 to 0.5 μm, the BET specific surface area is 0.25 to 100 m 2 /g, preferably 2 to 50 m 2 /g, and there is little variation in composition. In addition, about the average particle diameter of Me element-substituted barium titanate powder in this invention, 200 particle|grains were measured arbitrarily with the scanning electron microscope (SEM) photograph, and the average value was made into the average particle diameter.

In addition, in the titanium-based perovskite-type ceramic raw material powder obtained by performing the manufacturing method of the titanium-based perovskite-type ceramic raw material powder of the present invention, for the purpose of adjusting dielectric properties and temperature characteristics, if necessary, a compound containing sub-component elements , can be added to the titanium-based perovskite-type ceramic raw material powder. Examples of the subcomponent element-containing compound that can be used include rare earth elements of Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Li , Bi, Zn, Mn, Al, Si, Co, Ni, Cr, Fe, Ti, V, Nb, Mo, W, and a compound containing at least one element selected from the group consisting of Sn.

The subcomponent element-containing compound may be either an inorganic substance or an organic substance, and examples thereof include oxides, hydroxides, chlorides, nitrates, oxalates, carboxylates and alkoxides containing the above elements. Further, when the subcomponent element-containing compound is a compound containing a Si element, silica sol, sodium silicate, or the like can be used in addition to the above oxide. The above-mentioned subcomponent element-containing compound is used alone or in combination of two or more, and the amount or combination of the additive compound is appropriately selected according to the purpose.

The method of making the titanium-based perovskite-type ceramic raw material powder contain subcomponent elements is, for example, the titanium-based perovskite-type ceramic raw material powder obtained by performing the manufacturing method of the titanium-based perovskite-type ceramic raw material powder of the present invention, and the auxiliary component The organic acid barium titanyl powder of the present invention obtained by uniformly mixing the element-containing compound and then calcining, or the method for producing the organic acid barium titanyl powder of the present invention or the organic acid barium titanyl powder of the present invention, and the auxiliary component-containing compound A method of uniformly mixing and then calcining is mentioned.

The titanium-based perovskite-type ceramic raw material powder obtained by performing the manufacturing method of the titanium-based perovskite-type ceramic raw material powder of the present invention is, for example, including an auxiliary component element, conventionally known additives, organic binders, plasticizers, dispersants, etc. A ceramic sheet used for manufacturing a multilayer ceramic capacitor can be obtained by mixing and dispersing in a suitable solvent together with a compounding agent for slurrying and forming a sheet.

In order to produce a multilayer ceramic capacitor from a ceramic sheet, first, a conductive paste for forming internal electrodes is printed on one side of the ceramic sheet, dried, a plurality of ceramic sheets are laminated, and the ceramic sheet is pressed in the thickness direction to obtain a laminated body. Next, this laminate is heat-treated, subjected to a debonding agent treatment, and fired to obtain a fired body. In addition, when Ni paste, Ag paste, nickel alloy paste, copper paste, copper alloy paste, etc. are coated and baked on the sintered body, a multilayer ceramic capacitor can be obtained.

Further, for example, the titanium-based perovskite-type ceramic raw material powder obtained by performing the manufacturing method of the titanium-based perovskite-type ceramic raw material powder of the present invention is blended with a resin such as an epoxy resin, a polyester resin, a polyimide resin, When it is made of a resin sheet, a resin film, an adhesive, etc., it can be suitably used as a material for a printed wiring board or a multilayer printed wiring board, and is a common material for suppressing the difference in shrinkage between the internal electrode and the dielectric layer, an electrode ceramic circuit board, a glass ceramic circuit board , circuit periphery materials, and dielectric materials for inorganic EL and the like.

In addition, the titanium-based perovskite-type ceramic raw material powder obtained by performing the method for producing the titanium-based perovskite-type ceramic raw material powder of the present invention is used in reactions such as exhaust gas removal and chemical synthesis; It can be suitably used also as a surface modifier of a printing toner which imparts a cleaning effect.

Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these Examples.

Example

In the Example, the characteristic by the following method was measured.

(1) Molar ratio of Ba atom, Ca atom and Ti atom

The molar ratio of each atom was calculated based on the measured value of a fluorescent X-ray analyzer (manufactured by Rigaku Co., Ltd., ZSX100e).

(2) Average particle diameter of Me element-substituted barium titanyl oxalate powder

The particle size distribution was measured by the laser diffraction/scattering method using MT3000 manufactured by Microtrac Bell Corporation, and the particle diameter (D50) of 50% of the volume in the particle size distribution was taken as the average particle diameter.

(3) Average particle diameter of Me element-substituted barium titanate

Using S4800 manufactured by Hitachi High-Technologies, 200 particles were arbitrarily measured with a scanning electron microscope (SEM) photograph, and the average value was taken as the average particle diameter.

(4) Ca atom mapping analysis by EPMA

Using an electron probe microanalyzer (EPMA) (manufactured by Nippon Electronics Co., Ltd., JXA8500F), Ca atoms were analyzed by mapping.

(5) X-ray diffraction analysis of Me element-substituted barium titanyl oxalate powder

X-ray diffraction analysis was performed using UltimaIV manufactured by Rigaku Corporation.

(Example 1)

50.0 g of barium chloride dihydrate, 10.0 g of calcium chloride dihydrate, and 120.0 g of titanium tetrachloride were dissolved in 500 ml of pure water to prepare a mixed aqueous solution, which was used as solution A. In addition, the molar ratio of each element in the liquid A is shown in Table 1.

Next, 70.0 g of oxalic acid was melt|dissolved in 500 ml of 30 degreeC warm water, the oxalic acid aqueous solution was prepared, and this was set as B liquid.

Then, while maintaining the solution B (reaction solution after initiation of dropping) at 30° C., solution A was added at a rate of 4.2 ml/min over 120 minutes under stirring, and further aged at 30° C. under stirring for 60 minutes. After cooling, it was filtered to recover the barium calcium titanyl oxalate powder.

Then, the recovered barium calcium titanyl oxalate powder was repulped and washed with distilled water. Then, it was dried at 80° C. to obtain a calcium titanyl barium oxalate powder. The physical property values of the obtained barium calcium titanyl oxalate powder were as shown in Table 1. Further, the obtained barium calcium titanyl oxalate powder was calcined at 800° C., and the obtained barium calcium titanate powder was analyzed by mapping Ca atoms using an electron probe microanalyzer (EPMA) (JXA8500F, manufactured by Nippon Electronics Co., Ltd.). did The results are shown in FIG. 1 . From the result of FIG. 1, segregation of Ca atoms was not seen in the obtained barium calcium titanate powder, but it turned out that Ca is disperse|distributed uniformly. Further, as a result of elemental analysis of the obtained barium calcium titanate powder, Ca/Ba was 0.020 and (Ba+Ca)/Ti was 0.994.

Further, from the results of elemental analysis of the obtained barium calcium titanate powder and X-ray diffraction analysis of barium calcium titanyl oxalate obtained by adding solution A to solution B, barium calcium titanyl oxalate obtained in Example 1 was (Ba _0.080 Ca _0.020 ) was found to be _0.994 TiO(C ₂ O ₄ ) ₂ .4H ₂ O. The results of X-ray diffraction analysis are shown in FIG. 2 .

(Example 2)

40.0 g of barium chloride dihydrate, 20.0 g of calcium chloride dihydrate, and 120.0 g of titanium tetrachloride were dissolved in 500 ml of pure water to prepare a mixed aqueous solution, and this was used as solution A. In addition, the molar ratio of each element in the liquid A is shown in Table 1.

Next, 70.0 g of oxalic acid was melt|dissolved in 500 ml of 30 degreeC warm water, the oxalic acid aqueous solution was prepared, and this was set as B liquid.

Then, while maintaining the solution B (reaction solution after initiation of dropping) at 30° C., solution A was added at a rate of 4.2 ml/min over 120 minutes under stirring, and further aged at 30° C. under stirring for 60 minutes.

Subsequent operations were performed in the same manner as in Example 1. The physical property values of the obtained barium calcium titanyl oxalate powder were as shown in Table 1. Further, the obtained barium calcium titanyl oxalate powder was calcined, and the obtained barium calcium titanate powder was analyzed for mapping of Ca atoms using EPMA. The results are shown in FIG. 3 . From the result of FIG. 3, segregation of Ca atoms was not seen in the obtained barium calcium titanate powder, but it turned out that Ca is disperse|distributed uniformly. Further, as a result of elemental analysis of the obtained barium calcium titanate powder, Ca/Ba was 0.05 and (Ba+Ca)/Ti was 0.998.

Further, from the results of elemental analysis of the obtained barium calcium titanate powder and X-ray diffraction analysis of barium calcium titanyl oxalate obtained by adding solution A to solution B, the barium calcium titanyl oxalate obtained in Example 2 was (Ba _0.08 Ca _0.05 ) was found to be _0.998 TiO(C ₂ O ₄ ) ₂ .4H ₂ O. The results of X-ray diffraction analysis are shown in FIG. 2 .

(Example 3)

40.0 g of barium chloride dihydrate, 7.5 g of calcium chloride dihydrate, and 120.0 g of titanium tetrachloride were dissolved in 500 ml of pure water to prepare a mixed aqueous solution, and this was used as solution A. In addition, the molar ratio of each element in the liquid A is shown in Table 1.

Next, 70.0 g of oxalic acid was melt|dissolved in 500 ml of 30 degreeC warm water, the oxalic acid aqueous solution was prepared, and this was set as B liquid.

Then, while maintaining the solution B (reaction solution after initiation of dropping) at 30° C., solution A was added at a rate of 4.2 ml/min over 120 minutes under stirring, and further aged at 30° C. under stirring for 60 minutes.

Subsequent operations were performed in the same manner as in Example 1. The physical property values of the obtained barium calcium titanyl oxalate powder were as shown in Table 1. Further, the obtained barium calcium titanyl oxalate powder was calcined, and the obtained barium calcium titanate powder was analyzed for mapping of Ca atoms using EPMA. The results are shown in FIG. 4 . From the result of FIG. 4, segregation of Ca atoms was not seen in the obtained barium calcium titanate powder, but it turned out that Ca is disperse|distributed uniformly. Further, as a result of elemental analysis of the obtained barium calcium titanate powder, Ca/Ba was 0.02 and (Ba+Ca)/Ti was 0.991.

Further, from the results of elemental analysis of the obtained barium calcium titanate powder and X-ray diffraction analysis of barium calcium titanyl oxalate obtained by adding solution A to solution B, the barium calcium titanyl oxalate obtained in Example 3 was (Ba _0.08 Ca _0.02 ) was found to be _0.991 TiO(C ₂ O ₄ ) ₂ .4H ₂ O. The results of X-ray diffraction analysis are shown in FIG. 2 .

(Example 4)

52.0 g of barium carbonate, 4.7 g of calcium carbonate, and 120.0 g of titanium tetrachloride were dissolved in 420 ml of pure water to prepare a mixed aqueous solution, and this was used as solution A. In addition, the molar ratio of each element in the liquid A is shown in Table 1.

Next, 70.0 g of oxalic acid was dissolved in 420 ml of hot water at 30°C to prepare an aqueous oxalic acid solution, and this was used as liquid B.

Then, while maintaining the solution B (reaction solution after initiation of dropping) at 30° C., solution A was added at a rate of 3.5 ml/min over 120 minutes under stirring, and further aged at 30° C. under stirring for 60 minutes. After cooling, it was filtered to recover the barium calcium titanyl oxalate powder.

Then, the recovered barium calcium titanyl oxalate powder was repulped and washed with distilled water. Then, it was dried at 80° C. to obtain a calcium titanyl barium oxalate powder. The physical property values of the obtained barium calcium titanyl oxalate powder were as shown in Table 1. Further, the obtained barium calcium titanyl oxalate powder was calcined at 800° C., and the obtained barium calcium titanate powder was analyzed by mapping Ca atoms using an electron probe microanalyzer (EPMA) (manufactured by Nippon Electronics Co., Ltd., JXA8500F). . The results are shown in FIG. 5 . From the result of FIG. 5, segregation of Ca atoms was not seen in the obtained barium calcium titanate powder, but it turned out that Ca is disperse|distributed uniformly. Further, as a result of elemental analysis of the obtained barium calcium titanate powder, Ca/Ba was 0.026 and (Ba+Ca)/Ti was 0.998.

Further, from the results of elemental analysis of the obtained barium calcium titanate powder and X-ray diffraction analysis of barium calcium titanyl oxalate obtained by adding solution A to solution B, barium calcium titanyl oxalate obtained in Example 4 was (Ba _0.08 Ca _0.03 ) was found to be _0.998 TiO(C ₂ O ₄ ) ₂ .4H ₂ O. The results of X-ray diffraction analysis are shown in FIG. 2 .

(Example 5)

360.0 g of barium chloride dihydrate, 72.0 g of calcium chloride dihydrate, and 864.0 g of titanium tetrachloride were dissolved in 3600 ml of pure water to prepare a mixed aqueous solution, which was used as solution A. In addition, the molar ratio of each element in the liquid A is shown in Table 1.

Next, 504.0 g of oxalic acid was melt|dissolved in 3600 ml of 30 degreeC hot water, the oxalic acid aqueous solution was prepared, and this was made into B liquid.

Then, while maintaining the solution B (reaction solution after the start of dropping) at 30°C, solution A was added at a rate of 30 ml/min over 120 minutes under stirring, and further aged at 30°C under stirring for 60 minutes. After cooling, it was filtered to recover the barium calcium titanyl oxalate powder.

Then, the recovered barium calcium titanyl oxalate powder was repulped and washed with distilled water. Then, it was dried at 80° C. to obtain a calcium titanyl barium oxalate powder. The physical property values of the obtained barium calcium titanyl oxalate powder were as shown in Table 1. Further, the obtained barium calcium titanyl oxalate powder was calcined at 800° C., and the obtained barium calcium titanate powder was analyzed by mapping Ca atoms using an electron probe microanalyzer (EPMA) (manufactured by Nippon Electronics Co., Ltd., JXA8500F). . The results are shown in FIG. 6 . From the result of FIG. 6, segregation of Ca atoms was not seen in the obtained barium calcium titanate powder, but it turned out that Ca is disperse|distributed uniformly. Further, as a result of elemental analysis of the obtained barium calcium titanate powder, Ca/Ba was 0.025 and (Ba+Ca)/Ti was 0.994.

Further, from the results of elemental analysis of the obtained barium calcium titanate powder and X-ray diffraction analysis of barium calcium titanyl oxalate obtained by adding solution A to solution B, barium calcium titanyl oxalate obtained in Example 5 was (Ba _0.08 Ca _0.02 ) was found to be _0.994 TiO(C ₂ O ₄ ) ₂ .4H ₂ O. The results of X-ray diffraction analysis are shown in FIG. 2 .

(Comparative Example 1)

150.0 g of barium chloride dihydrate, 10.0 g of calcium chloride dihydrate, and 120.0 g of titanium tetrachloride were dissolved in 500 ml of pure water to prepare a mixed aqueous solution, and this was used as solution A. In addition, the molar ratio of each element in the liquid A is shown in Table 1.

Next, 70.0 g of oxalic acid was melt|dissolved in 500 ml of 30 degreeC warm water, the oxalic acid aqueous solution was prepared, and this was set as B liquid.

Then, while maintaining the B solution at 30° C., the A solution was added at a rate of 4.2 ml/min over 120 minutes under stirring, and further aged at 30° C. under stirring for 60 minutes. After cooling, it was filtered to recover the barium calcium titanyl oxalate powder.

Subsequent operations were performed in the same manner as in Example 1. The physical property values of the obtained barium calcium titanyl oxalate powder were as shown in Table 1. Further, the obtained barium calcium titanyl oxalate powder was calcined, and the obtained barium calcium titanate powder was analyzed for mapping of Ca atoms using EPMA. The results are shown in FIG. 7 . From the result of FIG. 7, it turned out that Ca atoms segregated in the obtained barium calcium titanate powder. Further, as a result of elemental analysis of the obtained barium calcium titanate powder, Ca/Ba was 0.020 and (Ba+Ca)/Ti was 1.000.

Further, from the result of elemental analysis of the obtained barium calcium titanate powder and X-ray diffraction analysis of barium calcium titanyl oxalate obtained by adding solution A to solution B, barium calcium titanyl oxalate obtained in Comparative Example 1 was (Ba _0.080 Ca _0.020 ) was found to be _1.000 TiO(C ₂ O ₄ ) ₂ ·4H ₂ O.

(Comparative Example 2)

27.0 g of barium chloride dihydrate, 5.4 g of calcium chloride dihydrate, and 64.1 g of titanium tetrachloride were dissolved in 180 ml of pure water to prepare a mixed aqueous solution, which was used as solution A. In addition, the molar ratio of each element in the liquid A is shown in Table 1.

Next, 32.5 g of oxalic acid was melt|dissolved in 140 ml of 55 degreeC warm water, the oxalic acid aqueous solution was prepared, and this was made into B liquid.

Then, while maintaining the B solution at 55° C., the A solution was added at a rate of 1.5 ml/min over 120 minutes under stirring, and further aged at 55° C. under stirring for 60 minutes. After cooling, it was filtered to recover the barium calcium titanyl oxalate powder.

Subsequent operations were performed in the same manner as in Example 1. The physical property values of the obtained barium calcium titanyl oxalate powder were as shown in Table 1. Further, the obtained barium calcium titanyl oxalate powder was calcined, and the obtained barium calcium titanate powder was analyzed for mapping of Ca atoms using EPMA. The results are shown in FIG. 8 . From the result of FIG. 8, it turned out that Ca atoms segregated in the obtained barium calcium titanate powder. Further, as a result of elemental analysis of the obtained barium calcium titanate powder, Ca/Ba was 0.020 and (Ba+Ca)/Ti was 0.999.

Further, from the results of elemental analysis of the obtained barium calcium titanate powder and X-ray diffraction analysis of barium calcium titanyl oxalate obtained by adding solution A to solution B, barium calcium titanyl oxalate obtained in Comparative Example 2 was (Ba _0.080 Ca _0.020 ) _0.999 TiO(C ₂ O ₄ ) ₂ 4H ₂ O was recognized.

From the results in Table 1 and FIGS. 1 to 8, in the barium calcium titanate obtained from the barium calcium titanyl oxalate of the Examples, the calcium atoms do not segregate uniformly, compared with the barium calcium titanate obtained from the barium calcium titanyl oxalate of the comparative example. distribution was found.

Claims (10)

A Me element-substituted organic acid barium titanyl in which a part of the Ba site is substituted with a Me element (Me represents at least one selected from Ca, Sr, and Mg),
The molar ratio of the sum of Ba and Me elements to Ti ((Ba+Me)/Ti) is 0.980 or more and less than 0.999, and the molar ratio of Me to Ba (Me/Ba) is 0.001 or more and 0.250 or less
Characterized in, Me element substituted organic acid barium titanyl powder. The method according to claim 1, wherein, in the electron probe microanalyzer (EPMA) analysis, the Me element is uniformly distributed in the particles of the Me element-substituted barium titanate powder obtained by calcining the Me element-substituted organic acid barium titanyl powder. Characterized in that, Me element substituted organic acid barium titanyl powder. The Me element-substituted barium titanate green body obtained by calcining the Me element-substituted organic acid barium titanyl powder using an electron probe microanalyzer (EPMA) analysis has a side surface of 205 µm on one side. Me element-substituted organic acid barium titanyl powder, characterized in that the CV value (standard deviation/average value) of Ca is 0.4 or less in the image analysis obtained by performing mapping analysis of 256 vertical and horizontal points at intervals of 0.8 µm to form a square range. By adding an aqueous solution obtained by mixing a barium compound, an elemental Me compound (Me represents at least one selected from Ca, Sr and Mg) and a titanium compound with water (solution A) to an aqueous solution of an organic acid (solution B), A method for producing a Me element substituted organic acid barium titanyl powder to obtain Me element substituted organic acid barium titanyl, the method comprising:
In the solution A, the molar ratio (Me/Ba) of the element Me to Ba is 0.020 or more and 5.000 or less, the molar ratio of Ba to Ti (Ba/Ti) is 0.300 or more and 1.200 or less, and the solution A and The mixing temperature of solution B is 10 to 50 ℃
A method for producing a Me element-substituted organic acid barium titanyl powder, characterized in that. The method of claim 4, wherein the barium compound is at least one selected from the group consisting of barium chloride, barium carbonate and barium hydroxide. The Me element-substituted organic acid barium titanyl according to claim 4 or 5, wherein the element Me compound is at least one selected from the group consisting of a chloride of an element of Me, a carbonate of an element of Me, and a hydroxide of an element of Me. A method for preparing the powder. The method for producing a Me element-substituted organic acid barium titanyl powder according to any one of claims 4 to 6, wherein the titanium compound is at least one selected from titanium tetrachloride and titanium lactate. The method for producing a Me element-substituted organic acid barium titanyl powder according to any one of claims 4 to 7, wherein the organic acid is at least one selected from the group consisting of oxalic acid, citric acid, malonic acid and succinic acid. . A method for producing a titanium-based perovskite type ceramic raw material powder, wherein the Me element-substituted barium titanate is obtained by calcining the Me element-substituted barium titanyl powder according to any one of claims 1 to 3 . A Me element substituted barium titanate powder is obtained by calcining the Me element substituted organic acid barium titanyl powder obtained by performing the method for producing the Me element substituted organic acid barium titanyl powder according to any one of claims 4 to 8. A method for producing a titanium-based perovskite-type ceramic raw material powder.

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