JP7029576B1 - Compounds, their manufacturing methods, and composite materials - Google Patents

Abstract

Provided is a new compound having a negative coefficient of thermal expansion and high insulation resistance. Composition formula Zr2.00-bMbSYSPZO12.00 + δ (In the formula, M is at least one selected from Ti, Ce, Sn, Mn, Hf, Ir, Pb, Pd, Cr, W, Mo, and is 0. ≦ b <2.00, 0 <Y <0.30, Z ≧ 2.00, δ are values determined to satisfy the charge neutrality condition), or the composition formula Zr2.00-bMbSYSPZO12. 00 + δ (In the formula, M is at least one selected from Ti, Ce, Sn, Mn, Hf, Ir, Pb, Pd, Cr, W, Mo, and 0 ≦ b <2.00, 0. .30 ≦ Y ≦ 1.00, Z> 2.00, and δ are values determined to satisfy the charge neutrality condition).

Description

The present invention relates to a novel compound showing a negative thermal expansion coefficient whose volume decreases as the temperature rises, a method for producing the same, and a composite material using the novel compound.

In technical fields where precision is required, such as electronic devices, optical devices, fuel cells, and sensors, for example, when a device is constructed by combining multiple materials, the difference in thermal expansion rate between the materials causes misalignment and interface peeling. , If a wire break occurs, it may cause a serious problem. Therefore, a technology for controlling thermal expansion is required. As one of the thermal expansion control techniques, a technique for controlling the overall thermal expansion coefficient by combining a material having a negative thermal expansion coefficient (also referred to as "negative thermal expansion material") is attracting attention.

As the temperature rises, many substances increase in volume due to thermal expansion. On the other hand, there are rarely negative thermal expansion materials having the property that the volume decreases when heated.
However, even if it is called a negative thermal expansion material, in general, most of the materials show negative thermal expansion only in a specific temperature range and show positive thermal expansion in other temperature ranges.

Examples of the negative thermal expansion material include β-eucriptite, zirconium tungate (ZrW ₂ O ₈ ), zirconium tungate phosphate (Zr ₂ WO ₄ (PO ₄ ) ₂ ), Zn _x Cd _1-x (CN). _2. Manganese nitrides, bismuth, nickel, iron oxides, etc. are known.

Further, Patent Document 1 discloses Bi _1-x Sb _x NiO ₃ (where x is 0.02 ≦ x ≦ 0.20) as a new negative thermal expansion material.

In Patent Document 2, as a new negative thermal expansion material, Zr _{2-a Ma} S _x P ₂ O _{12 + δ} (M is from Ti, Ce, Sn, Mn, Hf, Ir, Pb, Pd, Cr). It is at least one selected, a is 0 ≦ a <2, x is 0.4 ≦ x ≦ 1, and δ is a value determined so as to satisfy the charge neutrality condition). The compound characterized by the above is disclosed.

Japanese Unexamined Patent Publication No. 2017-48071 WO2019 / 167924 A1

Currently, the above-mentioned negative thermal expansion materials are used, and more excellent low thermal expansion is required. In addition, as the size of the member is reduced, the wiring is becoming thinner, so that higher insulation is also required.

Furthermore, the negative thermal expansion material disclosed in Patent Document 2 exhibits a negative thermal expansion rate in the range of room temperature to 500 ° C., and the larger the sulfur content (x), the more negative it is, especially at 100 to 180 ° C. It is attracting attention as a useful material because it is a material that exhibits the thermal expansion coefficient of and can also realize low density.
On the other hand, in a specific application, there is a demand for a material that exhibits a negative thermal expansion rate, particularly in the temperature range of room temperature to 100 ° C., room temperature to 200 ° C., or room temperature to 300 ° C. For example, in the case of controlling the thermal expansion coefficient of a resin material, when the negative thermal expansion material is added to the resin material as a positive thermal expansion material to adjust the thermal expansion coefficient, the melting point or the glass transition temperature of the resin material is low. In some cases, a negative thermal expansion material that exhibits a negative thermal expansion rate in the temperature range of room temperature to 100 ° C., room temperature to 200 ° C., or room temperature to 300 ° C. is required.

Therefore, the present invention is intended to provide a new compound having a composition different from the conventional one and exhibiting a negative thermal expansion coefficient and having a high insulation resistance.
More preferably, it does not provide new compounds that have high insulation resistance and that exhibit particularly good negative thermal expansion rates, especially in the temperature range from room temperature to 100 ° C, room temperature to 200 ° C, or room temperature to 300 ° C. Is to be.

In order to solve this problem, the present invention has a composition formula Zr _2.00-b M _{b SY} P _{ZO 12.00 + δ} (in the formula, M is Ti, Ce, Sn, Mn, Hf, Ir, Pb). , Pd, Cr, W, Mo, and 0 ≦ b <2.00, 0 <Y <0.30, Z ≧ 2.00, δ so as to satisfy the charge neutrality condition. We propose a compound (referred to as "the present compound 1") represented by (determined value).

The present invention also has a composition formula Zr _2.00-b M _{b SY} P _{ZO 12.00 + δ} (in the formula, M is Ti, Ce, Sn, Mn, Hf, Ir, Pb, Pd, Cr, It is at least one selected from W and Mo, and 0 ≦ b <2.00, 0.30 ≦ Y ≦ 1.00, Z> 2.00, and δ are values determined so as to satisfy the charge neutrality condition). A compound represented by (referred to as "the present compound 2") is proposed.

Both the compounds 1 and 2 proposed by the present invention show a negative thermal expansion rate. Therefore, it is possible to control the thermal expansion coefficient of the composite material which is a mixture by mixing with a material exhibiting a positive thermal expansion coefficient (referred to as "positive thermal expansion material"). Further, since both of the present compounds 1 and 2 are excellent in insulation resistance, they can be effectively used in the technical field where insulation resistance is required.

Further, the present compound 1 proposed by the present invention exhibits a remarkably excellent negative thermal expansion rate, especially in the temperature range from room temperature to 100 ° C. Therefore, it can be suitably used for controlling the thermal expansion rate in the temperature range from room temperature to 100 ° C. For example, it is possible to control the coefficient of thermal expansion in the temperature range from room temperature to 100 ° C. of the composite material obtained by mixing with the positive thermal expansion material.

Further, the present compound 2 proposed by the present invention exhibits a remarkably excellent negative thermal expansion rate, especially in the temperature range of room temperature to 200 ° C. and room temperature to 300 ° C. Therefore, it can be suitably used for controlling the thermal expansion rate in the temperature range of room temperature to 200 ° C. and room temperature to 300 ° C. For example, it is possible to control the thermal expansion rate in the temperature range of room temperature to 200 ° C. and room temperature to 300 ° C. of the composite material obtained by mixing with the positive thermal expansion material.

Next, the present invention will be described based on examples of embodiments. However, the present invention is not limited to the embodiments described below.

<Compound 1>
Hereinafter, the compound according to an example of the embodiment of the present invention (referred to as “the present compound 1”) will be described in detail.

The present compound 1 has a composition formula Zr _2.00-b M _b S _Y P ZO _{12.00 + δ} (in the formula, 0 ≦ b <2.00, 0 <Y <0.30, _Z ≧ 2.00). , Δ is a compound represented by (a value determined so as to satisfy the charge neutrality condition).

In the composition formula of this compound 1, when b is b = 0, Zr _2.00 SY P _{ZO 12.00 + δ} (in the formula, 0 < _Y <0.30, _Z ≧ 2.00, δ is It is a compound represented by (a value determined so as to satisfy the charge neutrality condition). On the other hand, when b is 0 <b <2.00, the compound is a compound in which a part of the Zr site is replaced with M.

In the composition formula of the present compound 1, M is preferably one or a combination of two or more selected from Ti, Ce, Sn, Mn, Hf, Ir, Pb, Pd, Cr, W and Mo.
The compound in which a part of the Zr site in Zr _2.00 S _Y P _{ZO 12.00 + δ} (in the formula, 0 <Y <0.30, _Z ≧ 2.00) is replaced with these elements M is a compound. Similar to the compound in which the Zr site is composed of only Zr, it can exhibit a negative thermal expansion rate and realize high insulation resistance.

In the composition formula of the present compound 1, "b" indicating the amount (atomic ratio) of the M element is preferably 0 or more and less than 2.00, particularly 0 or more or less than 1.50, and among them, 0 or more or It is more preferably 1.00 or less, and more preferably 0 or more or 0.80 or less.

In the composition formula of the present compound 1, "Y" indicating the amount (atomic ratio) of S (sulfur) is preferably larger than 0 and less than 0.30, and more than 0.10 or less than 0.30. Among them, it is more preferably 0.15 or more or less than 0.30, and more preferably 0.20 or more or less than 0.30.

Further, "Z" indicating the amount (atomic ratio) of P (phosphorus) is preferably 2.00 or more, and more preferably more than 2.40. On the other hand, it is preferably 3.50 or less, more preferably 3.00 or less, and even more preferably 2.80 or less.

Further, "δ" in the composition formula of the present compound 1 is a value determined so as to satisfy the charge neutrality condition, and is usually -2.50 or more and 1.00 or less. Among them, -2.00 or more or 0.50 or less, among them, -1.50 or more or 0.00 or less, among them, -1.50 or more or -0.50 or less, among them, -1.33 or more or -0. It may be less than .80. The "charge neutral condition" does not have to be completely neutral, and oxygen deficiency and oxygen excess composition within the allowable range of the compound are allowed.

The amount of each element excluding oxygen, that is, the amount of Zr, M, S and P can be completely dissolved and measured by ICP-OES. In addition, since it is difficult to accurately measure the amount of oxygen, the composition ratio estimated as electrically neutral from the chemical ratio of the elements other than oxygen is used.

Examples of the crystal phase present in compound 1 include α-Zr ₂ SP ₂ O ₁₂ phase (ICDD card number: 04-017-0937 or / and ICDD card number: 00-038-0489), and this crystal can be mentioned. Is the main phase, that is, in the X-ray diffraction pattern obtained by analyzing compound 1 by an X-ray diffraction method (XRD, Cu radiation source), it is preferable that the peak intensity derived from this crystal is the highest. That is, other crystal phases may be contained in a part thereof.

<Compound 2>
Hereinafter, the compound according to another example of the embodiment of the present invention (referred to as “the present compound 2”) will be described in detail.

The present compound 2 has a composition formula Zr _2.00-b M _b S _Y P ZO _{12.00 + δ} (in the formula, 0 ≦ b <2.00, 0.30 ≦ Y ≦ 1.00, _Z > 2). 0.00 and δ are compounds represented by (values determined to satisfy the charge neutrality condition).

In the composition formula of the present compound 2, when b is b = 0, Zr _2.00 SY P _{ZO 12.00 + δ} (in the formula, 0.30 ≦ _Y ≦ 1.00, _Z > 2.00, δ is a compound represented by (a value determined so as to satisfy the charge neutrality condition). On the other hand, when b is 0 <b <2.00, the compound is a compound in which a part of the Zr site is replaced with M.

In the composition formula of the present compound 2, M is preferably one or a combination of two or more selected from Ti, Ce, Sn, Mn, Hf, Ir, Pb, Pd, Cr, W and Mo.
A compound in which a part of the Zr site in Zr _2.00 S _Y P _{ZO 12.00 + δ} (in the formula, 0.30 ≤ Y ≤ 1.00, _Z > 2.00) is replaced with these elements M. Can exhibit a negative thermal expansion coefficient and realize high insulation resistance, similarly to the compound in which the Zr site is composed of only Zr.

In the composition formula of the present compound 2, "b" indicating the amount (atomic ratio) of the M element is preferably 0 or more and less than 2.00, particularly 0 or more or less than 1.50, and among them, 0 or more or It is more preferably 1.00 or less, and more preferably 0 or more or 0.80 or less.

In the composition formula of the present compound 2, "Y" indicating the amount (atomic ratio) of S (sulfur) is preferably 0.30 or more and 1.00 or less, and above all, 0.30 or more or 0.80 or less. Among them, it is more preferably 0.30 or more or 0.50 or less.

Further, "Z" indicating the amount (atomic ratio) of P (phosphorus) needs to be larger than 2.00. On the other hand, it is preferably 3.50 or less, more preferably 3.00 or less, and even more preferably 2.80 or less.

Further, "δ" in the composition formula of the present compound 2 is a value determined so as to satisfy the charge neutrality condition, and is usually -2.50 or more and 1.00 or less. Among them, -2.00 or more or 0.50 or less, among them, -1.50 or more or 0.00 or less, among them, -1.50 or more or -0.50 or less, among them, -1.33 or more or -0. It may be less than .80. The "charge neutral condition" does not have to be completely neutral, and oxygen deficiency and oxygen excess composition within the allowable range of the compound are allowed.

The amount of each element excluding oxygen, that is, the amount of Zr, M, S and P can be completely dissolved and measured by ICP-OES. In addition, since it is difficult to accurately measure the amount of oxygen, a composition ratio estimated as electrically neutral from the chemical ratios of elements other than oxygen shall be used.

Examples of the crystal phase present in compound 2 include α-Zr ₂ SP ₂ O ₁₂ phase (ICDD card number: 04-017-0937 or / and ICDD card number: 00-038-0489), and this crystal can be mentioned. Is the main phase, that is, in the X-ray diffraction pattern obtained by analyzing compound 2 by an X-ray diffraction method (XRD, Cu radiation source), it is preferable that the peak intensity derived from this crystal is the highest. That is, other crystal phases may be contained in a part thereof.

<Surface treatment>
Both of the present compounds 1 and 2 may be surface-treated.
Since all of the compounds 1 and 2 are surface-treated with a predetermined surface-treated compound, the insulating property and the chemical resistance are improved, which contributes to the improvement of the wettability with respect to the resin.

Examples of the surface treatment compound include silane coupling agents as surface treatment agents, aluminumate coupling agents, titanate coupling agents, zirconium coupling agents, organic compounds such as organic carboxylic acids and organic amines, and dioxide. Any of the inorganic compounds such as silicon, aluminum oxide, zinc oxide and titanium oxide can be used.

In particular, by using a silane coupling agent as a surface treatment agent as a surface treatment compound, the insulating property of the components constituting the compound of the present invention is improved, the component elution is prevented, and the wettability when mixed with a resin is improved. Shows a significant effect.

As the silane coupling agent as the surface treatment agent, various silane coupling agents such as epoxy-based, amino-based, vinyl-based, methacrylic-based, acrylic-based, mercapto-based, and alkyl-based agents can be used. Specific examples of the silane coupling agent include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropylmethyldiethoxysilane. , 8-Glysidoxyoctylmethyldimethoxysilane, 8-glycidoxyoctylmethyldimethoxysilane, 8-glycidoxyoctylmethyldiethoxysilane, 3-aminopropyltrimethoxysilane, vinyltrimethoxysilane, 3-triethoxysilyl -N- (1,3-dimethyl-butylidene) propylamine, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, p-styryltrimethoxy Silane, 3-methacryloxypropylmethyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isocyanate Propyltriethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, hexyltrimethoxysilane, hexyltri Examples thereof include ethoxysilane, octyltriethoxysilane, and decyltrimethoxysilane. These silane coupling agents may be used alone or in combination of two or more.

Examples of the carboxylic acid as a surface treatment agent include caproic acid (hexanoic acid), caproic acid (octanoic acid), caproic acid (decanoic acid), lauric acid (dodecanoic acid), myristic acid (tetradecanoic acid), and palmitic acid (hexadecanoic acid). Acid), stearic acid (octadecanoic acid), oleic acid, linolic acid, linolenic acid and the like can be mentioned.

Examples of the amine as the surface treatment agent include aliphatic amines. In particular, an aliphatic amine having 6 or more and 18 or less carbon atoms, particularly 10 or more and 18 or less carbon atoms can be preferably used. Specific examples thereof include hexylamine, octylamine, decylamine, laurylamine, oleylamine and stearylamine.

<D50>
In each of the present compounds 1 and 2, it is preferable that the volume cumulative particle size D50 at the cumulative volume of 50% by volume by the laser diffraction / scattering type particle size distribution measurement method is 0.05 μm or more and 100 μm or less.
If the D50 of the compounds 1 and 2 is 0.05 μm or more, the dispersibility in a substrate such as a resin is good, and if it is 100 μm or less, the smoothness of the molded product is good. preferable.
From this point of view, the D50 of the present compounds 1 and 2 is more preferably 0.1 μm or more, particularly preferably 0.5 μm or more, and more preferably 1 μm or more. On the other hand, it is more preferably 50 μm or less, more preferably 40 μm or less, and further preferably 30 μm or less.

<BET specific surface area>
It is preferable that the BET specific surface area of each of the compounds 1 and 2 is 1 m ² / g or more and 50 m ² / g or less.
When the BET specific surface area of the compounds 1 and 2 is 1 m ² / g or more, it is preferable because the smoothness of the molded product is good, for example, and when it is 50 m ² / g or less, it is dispersed in a substrate such as a resin. It is preferable because it has good properties.
From this point of view, the BET specific surface area of the compounds 1 and 2 is more preferably 2 m ² / g or more, particularly 5 m ² / g or more, particularly 10 m ² / g or more, and further 15 m ² / g or more. It is even more preferable to have it. On the other hand, it is more preferably 45 m ² / g or less.

<Volume resistivity>
The volume resistivity of the compounds 1 and 2 can be 2000 Ω · cm or more.
The volume resistivity is preferably high in applications where insulation is required.
From this point of view, the volume resistivity of the present compounds 1 and 2 is more preferably 10,000 Ω · cm or more, particularly preferably 100,000 Ω · cm or more, and more preferably 1,000,000 Ω · cm or more.

<Negative thermal expansion rate>
The compounds 1 and 2 show a negative thermal expansion rate. For example, it shows a negative thermal expansion rate in a temperature range of 30 ° C. to 100 ° C., a temperature range of 30 ° C. to 200 ° C., a temperature range of 30 ° C. to 300 ° C., and the like.

Among them, the present compound 1 exhibits a remarkably excellent negative thermal expansion rate, especially in the temperature range of 30 ° C to 100 ° C. Specifically, when heated to 30 ° C. to 100 ° C., the volume at 100 ° C. can shrink by 0.15% to 2.0% with respect to the volume at 30 ° C. Of these, 0.15% to 1.0%, of which 0.15% to 0.70%, and even more preferably 0.15% to 0.45%, are more preferable.
The lower limit of each of the above ranges is 0.15%, but the lower limit is preferably 0.20%, more preferably 0.25%.

On the other hand, the present compound 2 exhibits a remarkably excellent negative thermal expansion rate particularly in the temperature range of 30 ° C. to 200 ° C. and the temperature range of 30 ° C. to 300 ° C.
Specifically, when heated to 30 ° C. to 200 ° C., the volume at 200 ° C. can shrink by 1.0% to 3.0% with respect to the volume at 30 ° C. Of these, 1.0% to 2.0%, of which 1.1% to 2.0%, and even more preferably 1.1% to 1.5%, are more preferable. The lower limit of each range is 1.0%, but the lower limit is preferably 1.05%, more preferably 1.1%.
Further, when heated to 30 ° C. to 300 ° C., the volume at 300 ° C. can shrink by 1.0% to 3.0% with respect to the volume at 30 ° C. Of these, 1.0% to 2.0%, of which 1.1% to 2.0%, and even more preferably 1.1% to 1.5%, are more preferable.
The lower limit of each of the above ranges is 1.0%, but the lower limit is preferably 1.05%, more preferably 1.1%.

<Manufacturing method>
Next, a method for producing the present compounds 1 and 2 will be described. However, the production methods of the present compounds 1 and 2 are not limited to the production methods described below.

As an example of the method for producing the compounds 1 and 2, at least a Zr raw material, a phosphorus raw material, sulfuric acid, water, and, if necessary, an M raw material having the above composition formula (referred to as “M raw material”) are included. The mixture is hydrothermally treated to obtain a mixture after hydrothermal treatment, the mixture after hydrothermal separation is solid-liquid separated and washed to obtain a mixture after washing, the mixture after washing is dried to obtain a mixture after drying, and the mixture after drying is obtained. Can be mentioned as a method for producing a compound, which comprises firing at a temperature of 300 to 1000 ° C.
Hereinafter, this manufacturing method will be sequentially described.

Examples of the Zr raw material include zirconium oxychloride or its hydrate, zirconium chloride or its hydrate, zirconium oxyacetate or its hydrate, zirconium acetate or its hydrate, zirconium sulfate or its hydrate, oxynitrite. Zirconium or its hydrate, Zirconium nitrate or its hydrate, Zirconium carbonate or its hydrate, Zirconium ammonium carbonate or its hydrate, Zirconium sodium carbonate or its hydrate, Zirconium potassium or its hydrate, Etc. can be used. However, it is not limited to these.

Phosphorus raw materials include phosphoric acid (H ₃ PO ₄ ), diammonium hydrogen phosphate ((NH ₄ ) ₂ HPO ₄ ), ammonium dihydrogen phosphate (NH ₄ H ₂ PO ₄ ), and ammonium phosphate (NH ₄ (NH 4). PO ₄ ) ₃ ), pyrophosphoric acid, polyphosphoric acid can be used. However, it is not limited to these.

Examples of the M raw material include compounds containing the element M, for example, a sulfate of the element M or a solution thereof, a chloride salt or a solution thereof, a nitrate, an acetate, an oxide, a polyacid or a salt thereof, and the like. For example, when M is Ti, a titanium (IV) sulfate solution (Ti (SO ₄ ) ₂ ), a titanium (IV) chloride solution (TiCl ₄ ) can be mentioned, and when M is Ce, cerium sulfate can be mentioned. (Ce (SO ₄ ) ₂ ), cerium chloride (CeCl ₃ ) can be mentioned, and when M is Sn, first tin chloride, second tin chloride, tin sulfate, tin oxide (SnO ₂ ) can be mentioned. If M is Mn, manganese dioxide (MnO ₂ ) can be mentioned, and if M is W, tungsten trioxide (WO ₃ ), ammonium paratungstate ((NH ₄ ) ₁₀ ) can be mentioned. (H ₂ W ₁₂ O ₄₂ )), and when M is Mo, molybdenum trioxide (MoO ₃ ), hexaammonium heptamolybdate ((NH ₄ ) ₆ Mo ₇ O ₂₄ ), molybdenum acid. Diammonese ((NH ₄ ) ₂ MoO ₄ ) can be mentioned. However, it is not limited to these. Although the above compounds are described as anhydrous, hydrates are also included.

If necessary, ammonium sulfate, sulfur powder, or the like can be blended as the S (sulfur) raw material.

The Zr raw material, phosphoric acid, M raw material, sulfuric acid, and water, if necessary, are mixed, and the aqueous solution (mixture) obtained by stirring is hydrothermally treated to obtain a mixture after hydrothermal treatment. good.
At this time, the phosphorus raw material (P raw material) and the Zr raw material may be the same as the compound for which the P / Zr molar ratio is intended, or the phosphorus raw material may be increased.

As a method of hydrothermal treatment, for example, an aqueous solution (mixture) is placed in a sealable container, heated to 100 to 230 ° C., and allowed to stand for 3 hours to 3 days under pressure. Just do it.

Next, the mixture after hydrothermal treatment may be solid-liquid separated and washed to obtain a mixture after washing. That is, after the solid-liquid separation, water may be further added to separate the solid-liquid, or the washing may be performed by a method such as water flow washing. At this time, it is preferable to repeat washing as necessary.
By this washing, the excess S component can be washed.

Next, the post-washing mixture may be dried to obtain a post-drying mixture.
At this time, for example, the washed mixture may be heated and dried so that the product temperature is 60 to 150 ° C. However, the drying method may be appropriately adopted.
It has been confirmed that when a box-type dryer such as an AS ONE ETTAS constant temperature dryer is used, the set temperature of the dryer and the product temperature are almost the same.

Next, after drying, the mixture may be calcined to produce the present compound.
At this time, the post-drying mixture may be fired so that the product temperature is maintained at 300 to 1000 ° C., particularly 400 ° C. or higher or 1000 ° C. or lower, and particularly 400 ° C. or higher or 800 ° C. or lower for 1 to 24 hours. good.
For example, when a box-type electric furnace such as the KBF1150 ° C series electric furnace manufactured by Koyo Thermo System is used, it has been confirmed that the set temperature of the firing device, that is, the temperature inside the furnace and the product temperature are almost the same.

Further, when the surface treatment is carried out, the surface treatment may be carried out after crushing or crushing as necessary after the firing.
The surface treatment may be performed by using the above-mentioned surface treatment compound.
As a specific method for the surface treatment, the compounds 1 and 2 and the surface treatment compound may be dry-mixed or wet-mixed.
Wet mixing can be carried out using water, a mixed solvent in which water and a water-soluble organic solvent are mixed within the range of solubility in water, an organic solvent, or the like.

However, the production methods of the present compounds 1 and 2 are not limited to the above production methods.

<Use>
The present compounds 1 and 2 are mixed with a material having a positive thermal expansion coefficient (positive thermal expansion material) as a negative thermal expansion material, in other words, the negative thermal expansion material is dispersed in the positive thermal expansion material. Therefore, it is possible to form a composite material having a controlled thermal expansion coefficient.

Examples of the positive thermal expansion material include a resin material, a metal material, and a ceramic material.

<Explanation of words>
When expressed as "α to β" (α and β are arbitrary numbers) in the present specification, they mean "α or more and β or less" and are "preferably larger than α" or "preferably β". It also includes the meaning of "smaller".
Further, when expressed as "α or more" (α is an arbitrary number) or "β or less" (β is an arbitrary number), it means that "greater than α is preferable" or "less than β is preferable". Including intention.

The present invention will be further described with reference to the following examples. However, the following examples are not intended to limit the present invention in any way.

<Example 1>
ZrCl ₂ O ・ 8H ₂ O and phosphoric acid (H ₃ PO ₄ ) were dissolved in distilled water to 0.8 mol / L and then mixed, and then 20 ml and 6 ml of each of these aqueous solutions were mixed. 98% H ₂ SO ₄ was mixed and stirred with a stirrer for 90 minutes.
Next, the stirred aqueous solution (mixture) was poured into a closed container made of Teflon (registered trademark) and set in a pressure-resistant stainless steel outer cylinder. Then, the container set in this outer cylinder was placed in a hot air circulation oven and heated, and the state was maintained at 130 ° C. for 12 hours for hydroheat treatment.
After performing hydrothermal treatment, solid-liquid separation, removal of supernatant liquid, and further washing by adding water and repeating solid-liquid separation are performed, then poured into an evaporating dish and dried with hot air at an ambient temperature of 110 ° C. It was heated by a machine and dried.
The dried powder was placed in an electric furnace and calcined at 500 ° C. (product temperature) for 4 hours to obtain a compound (sample).

<Example 2>
ZrCl ₂ O ・ 8H ₂ O and phosphoric acid (H ₃ PO ₄ ) were dissolved in distilled water to 0.8 mol / L and then mixed, and then 20 ml and 4. 5 ml of 98% H ₂ SO ₄ was mixed and stirred with a stirrer for 90 minutes.
Next, the stirred aqueous solution (mixture) was poured into a closed container made of Teflon (registered trademark) and set in a pressure-resistant stainless steel outer cylinder. Then, the container set in this outer cylinder was placed in a hot air circulation oven and heated, and the state was maintained at 130 ° C. for 12 hours for hydroheat treatment.
After performing hydrothermal treatment, solid-liquid separation, removal of supernatant liquid, and further washing by adding water and repeating solid-liquid separation are performed, then poured into an evaporating dish and the solid content is heated with a hot air dryer at 110 ° C. It was dried.
The dried powder was placed in an electric furnace and calcined at 500 ° C. (product temperature) for 4 hours to obtain a compound (sample).

<Reference example 1>
ZrCl ₂ O ・ 8H ₂ O and NH ₄ H ₂ PO ₄ were dissolved in distilled water to 0.8 mol / L, respectively, followed by 20 ml and 6 ml of these aqueous solutions, respectively, 98% H ₂ SO ₄ Was mixed and stirred using a stirrer for 90 minutes.
Then, the stirred aqueous solution (mixture) was poured into a closed container made of Teflon (registered trademark) and set in a pressure-resistant stainless steel outer cylinder. Then, the container set in this outer cylinder was placed in a hot air circulation oven and heated, and the state was maintained at 180 ° C. for 2 days for hydroheat treatment.
After the hydrothermal treatment, a white precipitate was formed in the Teflon (registered trademark) container taken out. The solution containing this precipitate was poured into an evaporating dish and heated on a heater at about 100 ° C. to evaporate excess water. The evaporating dish was further dried in an electric furnace at 300 ° C. for 12 hours. Then, the sample dried at 300 ° C. (product temperature) was further calcined at 500 ° C. (product temperature) for 4 hours using an electric furnace to obtain a compound (sample).

<Reference example 2>
A compound (sample) was obtained in the same manner as in Reference Example 1 except that the firing temperature was set to 700 ° C. (product temperature).

<Example 3>
20 ml of an aqueous solution prepared with ZrCl _2O・_8H2O at 0.8 mol / L and _{20 ml of an aqueous solution prepared with ammonium dihydrogen phosphate (NH 4H 2 PO 4} ) at 1.1 mol / L were mixed, followed by Then, 6 ml of 98% H ₂ SO was mixed with this aqueous solution, and the mixture was stirred with a stirrer for 90 minutes.
Next, the stirred aqueous solution (mixture) was poured into a closed container made of Teflon (registered trademark) and set in a pressure-resistant stainless steel outer cylinder. Then, the container set in this outer cylinder was placed in a hot air circulation oven and heated, and the state was maintained at 130 ° C. for 12 hours for hydroheat treatment.
After performing hydrothermal treatment, solid-liquid separation, removal of supernatant liquid, and further washing by adding water and repeating solid-liquid separation are performed, then poured into an evaporating dish and the solid content is heated with a hot air dryer at 110 ° C. It was dried.
The dried powder was placed in an electric furnace and calcined at 500 ° C. (product temperature) for 4 hours to obtain a compound (sample).

<Example 4>
20 ml of an aqueous solution prepared with ZrCl _2O・_8H2O at 0.8 mol / L and 20 ml of an aqueous solution prepared with ammonium dihydrogen phosphate ₍ NH 4H ₂ PO ₄ ) at 0.9 mol / L were mixed, followed by Then, 6 ml of 98% H ₂ SO ₄ was mixed with this aqueous solution, and the mixture was stirred with a stirrer for 90 minutes.
Next, the stirred aqueous solution (mixture) was poured into a closed container made of Teflon (registered trademark) and set in a pressure-resistant stainless steel outer cylinder. Then, the container set in this outer cylinder was placed in a hot air circulation oven and heated, and the state was maintained at 130 ° C. for 12 hours for hydroheat treatment.
After performing hydrothermal treatment, solid-liquid separation, removal of supernatant liquid, and further washing by adding water and repeating solid-liquid separation are performed, then poured into an evaporating dish and the solid content is heated with a hot air dryer at 110 ° C. It was dried.
The dried powder was placed in an electric furnace and calcined at 500 ° C. (product temperature) for 4 hours to obtain a compound (sample).

<Example 5>
To 5 g of the compound (sample) obtained by the same procedure as in Example 1, 0.21 g of the silane coupling agent 3-isocyanatepropyltriethoxysilane was added as a surface treatment compound, and a mixer (Osaka Chemical Force Mill FM-) was added. After mixing in 1) for 2 minutes, heat treatment was performed under the conditions of 140 ° C. for 1 hour to obtain a compound (sample).

<Example 6>
To 5 g of the compound (sample) obtained by the same procedure as in Example 3, 0.20 g of 3-glycidoxypropyltrimethoxysilane as a silane coupling agent was added as a surface treatment compound, and the mixture was mixed with a mixer for 2 minutes. Then, heat treatment was performed at 140 ° C. for 1 hour to obtain a compound (sample).

<Example 7>
To 5 g of the compound (sample) obtained from the same procedure as in Example 3, 0.19 g of hexyltrimethoxysilane as a silane coupling agent was added as a surface treatment compound, mixed with a mixer 4 for 2 minutes, and then 140. A compound (sample) was obtained by heat treatment under the condition of ° C. for 1 hour.

<Example 8>
1.28 g of a 30% titanium sulfate solution was added to 20 ml of an aqueous solution prepared to 0.72 mol / L of ZrCl ₂ O / 8H ₂ O and mixed, and then ammonium dihydrogen phosphate (NH _{4H 2} PO ₄ ) was added thereto. 20 ml of an aqueous solution prepared at 0.9 mol / L was mixed, and then 6 ml of 98% H ₂ SO ₄ was mixed with this aqueous solution, and the mixture was stirred with a stirrer for 90 minutes.
Next, the stirred aqueous solution (mixture) was poured into a closed container made of Teflon (registered trademark) and set in a pressure-resistant stainless steel outer cylinder. Then, the container set in this outer cylinder was placed in a hot air circulation oven and heated, and the state was maintained at 130 ° C. for 12 hours for hydroheat treatment.
After performing hydrothermal treatment, solid-liquid separation, removal of supernatant liquid, and further washing by adding water and repeating solid-liquid separation are performed, then poured into an evaporating dish and the solid content is heated with a hot air dryer at 110 ° C. It was dried.
The dried powder was placed in an electric furnace and calcined at 500 ° C. (product temperature) for 4 hours to obtain a compound (sample).

<Example 9>
Add 2.56 g of a 30% titanium sulfate solution to 20 ml of an aqueous solution prepared at 0.64 mol / L of ZrCl ₂ O / 8H ₂ O and mix them, and then mix them with ammonium dihydrogen phosphate (NH _{4H 2} PO ₄ ). 20 ml of an aqueous solution prepared at 0.9 mol / L was mixed, and then 6 ml of 98% H ₂ SO ₄ was mixed with this aqueous solution, and the mixture was stirred with a stirrer for 90 minutes.
Next, the stirred aqueous solution (mixture) was poured into a closed container made of Teflon (registered trademark) and set in a pressure-resistant stainless steel outer cylinder. Then, the container set in this outer cylinder was placed in a hot air circulation oven and heated, and the state was maintained at 130 ° C. for 12 hours for hydroheat treatment.
After performing hydrothermal treatment, solid-liquid separation, removal of supernatant liquid, and further washing by adding water and repeating solid-liquid separation are performed, then poured into an evaporating dish and the solid content is heated with a hot air dryer at 110 ° C. It was dried.
The dried powder was placed in an electric furnace and calcined at 500 ° C. (product temperature) for 4 hours to obtain a compound (sample).

<Example 10>
Add 0.61 g of _CeCl 3.7H ₂ O to 20 ml of an aqueous solution prepared to 0.72 mol / L of ZrCl ₂ O / 8H ₂ O and mix them, and then mix them with ammonium dihydrogen phosphate ₍ NH 4H ₂ PO ₄ ). ) Was mixed with 20 ml of an aqueous solution prepared at 0.9 mol / L, and then 6 ml of 98% H ₂ SO ₄ was mixed with this aqueous solution, and the mixture was stirred with a stirrer for 90 minutes.
Next, the stirred aqueous solution (mixture) was poured into a closed container made of Teflon (registered trademark) and set in a pressure-resistant stainless steel outer cylinder. Then, the container set in this outer cylinder was placed in a hot air circulation oven and heated, and the state was maintained at 130 ° C. for 12 hours for hydroheat treatment.
After performing hydrothermal treatment, solid-liquid separation, removal of supernatant liquid, and further washing by adding water and repeating solid-liquid separation are performed, then poured into an evaporating dish and the solid content is heated with a hot air dryer at 110 ° C. It was dried.
The dried powder was placed in an electric furnace and calcined at 500 ° C. (product temperature) for 4 hours to obtain a compound (sample).

<Example 11>
1.22 g of CeCl _3.7H2O was added to 20 ml of an aqueous solution prepared to prepare ZrCl _2O / _8H2O to 0.64 mol / L and mixed, and ammonium dihydrogen phosphate (NH _{4H 2} PO ₄ ) was added thereto. 20 ml of an aqueous solution prepared to 0.9 mol / L was mixed, and then 6 ml of 98% H ₂ SO ₄ was mixed with this aqueous solution, and the mixture was stirred with a stirrer for 90 minutes.
Next, the stirred aqueous solution (mixture) was poured into a closed container made of Teflon (registered trademark) and set in a pressure-resistant stainless steel outer cylinder. Then, the container set in this outer cylinder was placed in a hot air circulation oven and heated, and the state was maintained at 130 ° C. for 12 hours for hydroheat treatment.
After performing hydrothermal treatment, solid-liquid separation, removal of supernatant liquid, and further washing by adding water and repeating solid-liquid separation are performed, then poured into an evaporating dish and the solid content is heated with a hot air dryer at 110 ° C. It was dried.
The dried powder was placed in an electric furnace and calcined at 500 ° C. (product temperature) for 4 hours to obtain a compound (sample).

<Example 12>
To 20 ml of an aqueous solution prepared to prepare 0.9 mol / L of ammonium dihydrogen phosphate (NH 4H ₂ PO ₄ ), 1.57 g of ammonium paratungstate _{parapentahydrate} was added, and this was added to ZrCl _{2O ・ 8H 2 O.} Was added to and mixed with 20 ml of an aqueous solution prepared at 0.72 mol / L, and then 6 ml of 98% H ₂ SO ₄ was mixed with this aqueous solution and stirred with a stirrer for 90 minutes.
Next, the stirred aqueous solution (mixture) was poured into a closed container made of Teflon (registered trademark) and set in a pressure-resistant stainless steel outer cylinder. Then, the container set in this outer cylinder was placed in a hot air circulation oven and heated, and the state was maintained at 130 ° C. for 12 hours for hydroheat treatment.
After performing hydrothermal treatment, solid-liquid separation, removal of supernatant liquid, and further washing by adding water and repeating solid-liquid separation are performed, then poured into an evaporating dish and the solid content is heated by a hot air dryer in an atmosphere of 110 ° C. And dried.
The dried powder was placed in an electric furnace and calcined at 500 ° C. (product temperature) for 4 hours to obtain a compound (sample).

<Example 13>
To 20 ml of an aqueous solution prepared to prepare 0.9 mol / L of ammonium dihydrogen dihydrogen phosphate (NH 4H ₂ PO ₄ ), 0.90 g of _hexaammonium hexaammonium tetrahydrate tetrahydrate was added, and this was added to ZrCl ₂ O ・ 8H ₂ . O was added and mixed with 20 ml of an aqueous solution prepared at 0.72 mol / L, and then 6 ml of 98% H ₂ SO ₄ was mixed with this aqueous solution and stirred with a stirrer for 90 minutes.
Next, the stirred aqueous solution (mixture) was poured into a closed container made of Teflon (registered trademark) and set in a pressure-resistant stainless steel outer cylinder. Then, the container set in this outer cylinder was placed in a hot air circulation oven and heated, and the state was maintained at 130 ° C. for 12 hours for hydroheat treatment.
After performing hydrothermal treatment, solid-liquid separation, removal of supernatant liquid, and further washing by adding water and repeating solid-liquid separation are performed, then poured into an evaporating dish and the solid content is heated with a hot air dryer at 110 ° C. It was dried.
The dried powder was placed in an electric furnace and calcined at 500 ° C. (product temperature) for 4 hours to obtain a compound (sample).

(Composition analysis)
The composition (atomic ratio) of the prepared compound (sample) was analyzed using ICP-OES (Inductivity Coupled Plasma Optical Emission Spectrometry).

= ICP-OES =
-ICP-OES equipment used: 700 series, ICP-OES (Agilent Technologies Co., Ltd.)

(D50)
The prepared compound (sample) was placed in pure water and irradiated with ultrasonic waves (40 W, 3 minutes) to disperse it, and then a particle size distribution measuring device (Microtrack (trade name) manufactured by Microtrac Bell Co., Ltd.). MT-3300EXII (model number) ”) was used to measure the volume cumulative particle size D50 at a cumulative volume of 50% by volume by a laser diffraction / scattering type particle size distribution measurement method.

(BET specific surface area)
Using a specific surface area measuring device (Mt. The BET specific surface area (SSA (BET)) of the prepared compound (sample) was measured in accordance with "(3.5) One-point method of the flow method". At that time, a mixed gas of helium as a carrier gas and nitrogen as an adsorbent gas was used. The degassing condition was 300 ° C. for 10 minutes.

(Volume resistivity)
The prepared compound (sample) was compressed at a pressure of 63 MPa using a powder resistance measuring system MCP-PD51 manufactured by Mitsubishi Chemical Analytech Co., Ltd., and the volume resistivity was measured according to the four-terminal method. For the sample exceeding the measurement upper limit of this device, pellets compressed at a pressure of 63 MPa were separately prepared and measured using a high resistance meter Hiresta UX / MCP-HT800 manufactured by Mitsubishi Chemical Analytech.

(Thermal expansion rate)
The expansion rate of the lattice volume of the prepared compound (sample) was measured by the following method.
A multipurpose sample high temperature device unit was attached to the following powder X-ray diffractometer, and the X-ray diffraction pattern was measured at 30 ° C. and 100 ° C. The measurement was started after standing for 10 minutes after reaching the target temperature.
The crystal structure was refined using the obtained X-ray diffraction pattern and analysis software (PDXL2), and the lattice constant at each temperature was calculated. The lattice volume was calculated from the lattice constant.
In the table, the lattice volume expansion rate at 30 to 100 ° C., that is, the lattice volume at 100 ° C. (referred to as “100 ° C. volume”) based on the lattice volume at 30 ° C. (referred to as “30 ° C. volume”). The changed ratio of, that is, ((30 ° C. volume-100 ° C. volume) / 30 ° C. volume) × 100 was calculated and shown as the volume expansion rate (%).
Similarly, the lattice volume expansion rate at 30 to 200 ° C. and the lattice volume expansion rate at 30 to 300 ° C. were calculated and shown in the table.

[High temperature XRD]
・ Equipment used: Ultima IV (Rigaku Co., Ltd.)
・ Atmosphere: Air
・ Tube current / tube voltage: 40kV / 40mA
・ Target: Cu
・ Step width: 0.02 °
-Measurement range (scanning speed): 10 to 80 ° (4 ° / min)
-Measurement temperature: 30 ° C, 100 ° C, 200 ° C, 300 ° C

From the above examples and the test results conducted by the present inventor so far, the composition formula Zr _2.00-b M _b S _Y P _{ZO 12.00 + δ} (in the formula, M is Ti, Ce, Sn, It is at least one selected from Mn, Hf, Ir, Pb, Pd, Cr, W, and Mo, and 0 ≦ b <2.00, 0 <Y <0.30, Z ≧ 2.00, and δ are charges. This compound 1 represented by (a value determined so as to satisfy the neutral condition) and the composition formula Zr _2.00-b M _{b SY} P _{ZO 12.00 + δ} (in the formula, M is Ti, Ce). , Sn, Mn, Hf, Ir, Pb, Pd, Cr, W, Mo, and 0 ≦ b <2.00, 0.30 ≦ Y ≦ 1.00, Z> 2. It was found that all of the present compounds 2 represented by (00 and δ are values determined so as to satisfy the charge neutrality condition) show a negative thermal expansion coefficient and are excellent in insulation resistance.

The compounds obtained in Examples 1, 2 and 5 have the α-Zr ₂ SP ₂ O ₁₂ phase (ICDD card number: 00-038-0489) as the main phase in the diffraction pattern obtained by X-ray diffraction. It was confirmed that it existed.
The compounds obtained in Examples 3, 4, 6-13 and Reference Examples have the α-Zr ₂ SP ₂ O ₁₂ phase (ICDD card number: 04-017-0937) in the diffraction pattern obtained by X-ray diffraction. ) Was confirmed to exist as the main phase.

Regarding the negative thermal expansion coefficient, it was found that all of the compounds 1 and 2 exhibited a negative thermal expansion coefficient in the temperature range of 30 to 100 ° C., 30 to 200 ° C., and 30 to 300 ° C.
Above all, it was found that the present compound 1 exhibited a remarkably excellent negative thermal expansion rate in the temperature range from room temperature (30 ° C.) to 100 ° C.
For example, Examples 1, 2, 5 and 9 are characterized in that the amount of S (Y) is small and the amount of P is large as compared with Reference Examples 1 and 2. It was confirmed that these Examples 1, 5, and 9 showed a better negative thermal expansion rate in the temperature range of 30 ° C to 100 ° C. This is because the atomic ratio (Y) of S is less than 0.30 and the atomic ratio (Z) of P is 2.00 or more, so that the structure as a compound is stable and the room temperature (30 ° C.) It is presumed that the negative thermal expansion rate is remarkably excellent in the temperature range of 100 ° C.

On the other hand, it was found that the present compound 2 exhibited a remarkably excellent negative thermal expansion rate in the temperature range of room temperature (30 ° C.) to 200 ° C. and the temperature range of room temperature (30 ° C.) to 300 ° C.
For example, Examples 3, 4, 6-8, and 10-13 have a smaller amount of S (Y) and a larger amount of P than Reference Examples 1 and 2, while compared with Examples 1 and 2. And, it has a feature that the amount of S (Y) is large and the amount of P is large. It was confirmed that Examples 3, 4, 6-8, and 10-13 show a more excellent negative thermal expansion rate in the temperature range of 30 ° C to 200 ° C and the temperature range of 30 ° C to 300 ° C. Was done. This is because the atomic ratio (Y) of S is 0.30 or more and 1.00 or less, and the atomic ratio (Z) of P is larger than 2.00, so that the temperature range from room temperature to 200 ° C. and room temperature are satisfied. It is presumed that it exhibits a remarkably excellent negative thermal expansion rate in the temperature range of 300 ° C.

The composition formula: Zr _2.00 SY P _{ZO 12.00 + δ} (in the formula, 0 < _Y <0.30, _Z ≧ 2.00) and Zr _{2.00 SY} P _{ZO 12.00} . Regarding the compound represented by _{+ δ} (in the formula, 0.30 ≦ Y ≦ 1.00, Z> 2.00), the Zr site thereof is based on the findings disclosed in Patent Document 2 (WO2019 / 167924 A1). A compound in which a part of the compound is substituted with an element such as Ti, Ce, Sn, Mn, Hf, Ir, Pb, Pd, Cr, W, Mo also exhibits a negative thermal expansion rate and, like the above compound, also exhibits a negative thermal expansion rate. It can be inferred that high insulation resistance can be realized.

Claims (16)

Composition formula Zr _2.00-b M _b S _Y P _{ZO 12.00 + δ} (In the formula, M is selected from Ti, Ce, Sn, Mn, Hf, Ir, Pb, Pd, Cr, W and Mo. A compound represented by 0 ≦ b <2.00, 0 <Y <0.30, Z ≧ 2.00, and δ are values determined so as to satisfy the charge neutrality condition). Composition formula Zr _2.00-b M _b S _Y P _{ZO 12.00 + δ} (In the formula, M is selected from Ti, Ce, Sn, Mn, Hf, Ir, Pb, Pd, Cr, W and Mo. 0≤b <2.00, 0.30≤Y≤1.00, Z> 2.00, δ are values determined to satisfy the charge neutrality condition). .. The compound according to claim 1, wherein the compound exhibits a negative thermal expansion rate. The compound according to claim 2, wherein the compound exhibits a negative thermal expansion rate. The compound according to claim 1 or 3, wherein the 100 ° C. volume shrinks 0.15% to 2.0% with respect to the 30 ° C. volume when heated to 30 ° C. to 100 ° C. The compound according to claim 2 or 4, wherein the volume at 200 ° C. shrinks by 1.0% to 3.0% with respect to the volume at 30 ° C. when heated to 30 ° C. to 200 ° C. The invention according to any one of claims 1 to 6, wherein the volume at 300 ° C. shrinks by 1.0% to 3.0% with respect to the volume at 30 ° C. when heated to 30 ° C. to 300 ° C. Compound. A molded body obtained by compressing a powder made of the compound according to any one of claims 1 to 7, and having a volume resistivity of 2000 Ω · cm or more. A powder comprising the compound according to any one of claims 1 to 7, which has a volume resistivity of 2000 Ω · cm or more when compressed at a pressure of 63 MPa to form a molded body . A powder made of the compound according to any one of claims 1 to 7, wherein the cumulative volume particle size D50 at a cumulative volume of 50% by volume measured by a laser diffraction / scattering particle size distribution measurement method is 0.05 μm or more and 100 μm or less. Powder . A powder comprising the compound according to any one of claims 1 to 7, having a BET specific surface area of 1 m ² / g or more and 50 m ² / g or less. A powder comprising the compound according to any one of claims 1 to 7, which has been surface-treated with a surface-treated compound. The powder according to claim 12 , wherein the surface-treated compound is a silane coupling agent. A composite in which the compound according to any one of claims 1 to 7 or the powder according to any one of claims 9 to 12 is mixed with or / or dispersed in a positive thermal expansion material. material. The method for producing a compound according to any one of claims 1 to 7 .
A mixture containing at least a Zr raw material, a phosphorus raw material, sulfuric acid, water, and, if necessary, a raw material of M having the above composition formula is hydrothermally treated to obtain a mixture after hydrothermal treatment, and the post-hydrothermal mixture is solidified. A method for producing a compound, which comprises liquid separation and washing to obtain a mixture after washing, drying the mixture after washing to obtain a mixture after drying, and firing the mixture after drying at a temperature of 300 to 1000 ° C. The method for producing a powder according to claim 12 or 13 .
A mixture containing at least a Zr raw material, a phosphorus raw material, sulfuric acid, water, and, if necessary, a raw material of M having the above composition formula is hydrothermally treated to obtain a mixture after hydrothermal treatment, and the post-hydrothermal mixture is solidified. Liquid separation and washing are performed to obtain a post-cleaning mixture, the post-cleaning mixture is dried to obtain a post-drying mixture, the post-drying mixture is fired at a temperature of 300 to 1000 ° C., and then the surface is used with a surface treatment compound. A method for producing a powder , which comprises performing a treatment.