JP2018154505A - Method of manufacturing s12a7 electride compound, and s12a7 electride compound sintered body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing an S12A7 electride compound comprising a relatively flat surface.SOLUTION: A method of manufacturing an S12A7 electride compound comprising the steps of preparing raw material containing an aluminum compound and a strontium compound (1-1); preparing calcined powder via heat treatment of the raw material (1-2), the calcined powder being any of (i) powder containing strontium aluminate, (ii) powder containing aluminum oxide or strontium oxide, and (iii) powder containing the strontium aluminate and at least one of aluminum oxide and strontium oxide; and holding a treated body containing the calcined powder and a halogen compound in a range of 1250°C to 1480°C under a reducing atmosphere in a state of being pressurized in a pressure range of 1 kg/cmto 200 kg/cm(1-3).SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for producing an S12A7 electride compound and a sintered body of an S12A7 electride compound.

The S12A7 electride compound has a representative composition represented by 12SrO.7Al ₂ O ₃ and has voids (cages) formed by a three-dimensionally connected skeleton. In this cage, anions and electrons are included, and thereby conductivity is developed.

Such S12A7 electride compounds are, for example,
(1) preparing a raw material containing an aluminum source, a halogen source, and a strontium source;
(2) a step of heat-treating the raw material to synthesize a compound having a cage, wherein the cage includes ions of the first halogen;
(3) subjecting the synthesized compound to a reduction heat treatment at a temperature in the range of 1150 ° C. to 1530 ° C. in a reducing atmosphere;
It can manufacture by implementing (patent document 1).

Japanese Patent Laid-Open No. 2006-160150

  An S12A7 electride compound can be produced by the method described in Patent Document 1 described above.

  However, in the above-described method, the sintered body of the S12A7 electride compound obtained after the heat treatment (hereinafter also simply referred to as “sintered body”) has a deformed surface due to warpage and undulation, and has good flatness. It tends to be difficult to obtain a sintered body. Therefore, in the above-described manufacturing method, processing (post-treatment) for flattening the surface of the sintered body is necessary after the heat treatment.

  Here, the flatness is defined as “the magnitude of the deviation from the geometrically correct plane of the planar feature”. That is, the flatness of a certain target surface is obtained as the minimum distance between the two planes when the planes parallel to each other are arranged above and below the target surface so as to include the most convex portion and the most concave portion of the target surface. It is done.

  Such post-treatment for flattening is not a problem when the sintered body is small. However, when a large-sized sintered body is manufactured, the post-process is extremely complicated and may cause a problem of an increase in manufacturing cost.

  This invention is made | formed in view of such a problem, and this invention provides the manufacturing method of the S12A7 electride compound which can obtain the sintered compact which has a comparatively flat surface after heat processing. For the purpose. Another object of the present invention is to provide a sintered body of an S12A7 electride compound having a relatively flat surface.

In the present invention, a method for producing an S12A7 electride compound,
(1-1) preparing a raw material containing an aluminum compound and a strontium compound;
(1-2) A step of heat-treating the raw material to prepare a calcined powder,
(I) a powder comprising strontium aluminate,
(Ii) a powder comprising aluminum oxide and strontium oxide, or (iii) a powder comprising at least one of aluminum oxide and strontium oxide and strontium aluminate,
A step that is either
(1-3) wherein the object to be processed comprising a calcined powder and a halogen ^compound, in a pressurized state at a pressure in the range of ^{1kg / cm 2 ~200kg / cm 2} , under a reducing atmosphere, the 1250 ℃ ~1480 ℃ A process of holding in the range;
A manufacturing method is provided.

Further, in the present invention, a sintered body of S12A7 electride compound,
The electron density is 3 × 10 ²⁰ cm ⁻³ or more, the thickness is 5 mm or more,
The sintered body has a main surface,
The area of the main surface is 15 cm ² or more,
A sintered body having a flatness of the main surface of 3 mm or less is provided.

  In the present invention, a method for producing an S12A7 electride compound capable of obtaining a sintered body having a relatively flat surface after heat treatment can be provided. Moreover, in this invention, the sintered compact of the S12A7 electride compound which has a comparatively flat surface can be provided.

It is the flowchart which showed typically an example of the manufacturing method of the S12A7 electride compound by one Embodiment of this invention. It is the figure which showed typically the example of 1 structure of the apparatus used when pressurizing and heat-processing a to-be-processed object. It is the figure which showed typically the usage condition of the apparatus shown in FIG. It is the flowchart which showed typically an example of another manufacturing method of the S12A7 electride compound by one Embodiment of this invention. It is the chart which showed an example of the result of the X-ray diffraction analysis of the sample manufactured in the Example.

  First, definitions of terms used in the present application will be described.

In the present application, the “S12A7 compound” is a 12SrO · 7Al ₂ O ₃ compound having a cage structure and a compound having the same crystal structure (homogeneous compound), and less than a maximum of 50 mol% of SrO Means a compound substituted with CaO, MgO and / or BaO. As the equivalent of the isomorphic compound of S12A7 compounds, 12CaO · _7Al 2 _{O 3.} The substitution amount of CaO, MgO and / or BaO to SrO is preferably less than 40 mol%, more preferably less than 30 mol%, still more preferably less than 20 mol%, and particularly preferably less than 10 mol%.

  In this application, as long as the S12A7 electride compound has an S12A7 crystal structure composed of strontium (Sr), aluminum (Al), and oxygen (O), strontium (Sr), aluminum (Al), and oxygen (O ) May be substituted with another atom or atomic group. For example, a part of strontium (Sr) is substituted with one or more atoms selected from the group consisting of magnesium (Mg), calcium (Ca), barium (Ba), lithium (Li), and sodium (Na). May be. A part of aluminum (Al) may be substituted with one or more atoms selected from the group consisting of silicon (Si), germanium (Ge), boron (B), and gallium (Ga). A part of oxygen (O) may be substituted with one or more atoms selected from the group consisting of nitrogen (N), fluorine (F) and chlorine (Cl).

In the present application, the cage of the S12A7 electride compound includes oxide ions (O ²⁻ , O ⁻ , O ₂ ⁻ ), hydroxide ions (OH ⁻ ), hydride ions (H ⁻ , H ₂ ^−). , H ²⁻ ), and / or anions such as halide ions (F ⁻ , Cl ⁻ , Br ⁻ , I ⁻ ), sulfide ions (S ²⁻ ), and nitrogen (N) anions. Anions may be included.

However, in the above definition, the ratio of SrO (including a substituted compound when it includes a substituted compound. The same shall apply hereinafter) and Al ₂ O ₃ (including a substituted compound when including a substituted compound. The same shall apply hereinafter) It is not necessarily 12: 7. That is, as long as the “S12A7 compound” can maintain the above crystal structure, the ratio (molar ratio) of SrO and Al ₂ O ₃ may deviate from 12: 7. For example, the ratio of SrO: Al ₂ O ₃ may be in the range of 11: 8 to 13: 6. For example, the ratio of SrO: Al ₂ O ₃ is preferably in the range of 11.3: 7.7 to 12.8: 6.2, 11.5: 7.5 to 12.6: 6.4. More preferably, it is in the range of 11.7: 7.3 to 12.4: 6.6, and more preferably in the range of 11.9: 7.1 to 12.2: 6.8. It is particularly preferred that Ideally it is about 12: 7.

  In the present application, the “S12A7 electride compound” means a conductive S12A7 compound in which a part of the anion contained in the cage is replaced with an electron in the “S12A7 compound”.

  Accordingly, the “S12A7 compound” includes a conductive “S12A7 electride compound” and a non-conductive “S12A7 compound”.

Here, the electron density of the S12A7 electride compound is measured by two methods.
When the electron density of the S12A7 electride compound is 1.0 × 10 ¹⁸ cm ⁻³ to less than 1.0 × 10 ²⁰ cm ⁻³ , the electron density of the S12A7 electride compound is determined from the signal intensity of electron spin resonance (ESR). Desired. Copper sulfate pentahydrate (CuSO ₄ .5H ₂ O) is used as a standard sample. When the electron density of the S12A7 electride compound is 1.0 × 10 ²⁰ cm ⁻³ or more, the electron density of the S12A7 electride compound can be measured by an iodine titration method. In the iodometric titration method, a sample made of S12A7 electride compound is first immersed in a 5 mol / l iodine aqueous solution. Next, hydrochloric acid is added to the aqueous iodine solution to dissolve the sample. Next, the amount of unreacted iodine contained in this solution is detected by titration with sodium thiosulfate. In this method, by dissolution of the sample, iodine in the aqueous iodine solution is ionized by the following reaction:

I ₂ + 2e ⁻ → 2I ⁻ (1) Formula

When titrating an aqueous iodine solution with sodium thiosulfate,

2Na ₂ S ₂ O ₃ + I ₂ → 2NaI + Na ₂ S ₄ O ₆ (2) Formula

By this reaction, unreacted iodine is changed to sodium iodide. By subtracting the amount of iodine detected by titration from equation (2) from the amount of iodine present in the initial solution, the amount of iodine consumed in the reaction of equation (1) is calculated. Thereby, the electron density in the sample of a S12A7 electride compound can be measured.

(Method for producing S12A7 electride compound according to one embodiment of the present invention)
Hereinafter, with reference to drawings, the manufacturing method of the S12A7 electride compound by one Embodiment of this invention is demonstrated in detail.

  In FIG. 1, an example of the manufacturing method of the S12A7 electride compound by one Embodiment of this invention is shown roughly.

As shown in FIG. 1, a method for producing an S12A7 electride compound according to an embodiment of the present invention (hereinafter simply referred to as “first production method”)
A step of preparing a raw material, wherein the raw material includes an aluminum compound and a strontium compound (step S110);
Heat treating the raw material to prepare calcined powder (step S120);
Wherein the object to be processed comprising a calcined powder and a halogen ^compound, in a pressurized state at a pressure in the range of ^{1kg / cm 2 ~200kg / cm 2} , under a reducing atmosphere, maintained in the range of 1250 ℃ ~1480 ℃ A process (step S130);
Have

  Hereinafter, each step will be described in detail.

(Step S110)
First, raw materials are prepared.

  The raw material includes an aluminum compound and a strontium compound.

  Examples of the aluminum compound include aluminum oxide, aluminum hydroxide, aluminum sulfate, aluminum nitrate, aluminum nitride, aluminum carbide, aluminum boride, and an organic aluminum compound. Among these, aluminum oxide and aluminum hydroxide are preferable. Aluminum oxide (alumina) may have any crystal structure such as α-alumina, γ-alumina, and δ-alumina. In particular, α-aluminum oxide (alumina) is preferable.

  Examples of strontium compounds include strontium carbonate, strontium oxide, strontium hydroxide, strontium hydroxide hydrate, strontium bicarbonate, strontium sulfate, strontium metaphosphate, strontium oxalate, strontium acetate, strontium nitrate, and organic strontium compounds Is mentioned. Among these, strontium carbonate, strontium oxide, strontium hydroxide and hydrates thereof are preferable, and strontium carbonate is particularly preferable.

  Note that the aluminum compound and the strontium compound are not necessarily limited to one substance, and the aluminum compound and / or the strontium compound may be a plurality of substances.

The aluminum compound and the strontium compound in the raw material are prepared so that the composition of the S12A7 electride compound obtained by the first production method is included in the aforementioned range. For example, in the S12A7 electride compound obtained by the first production method, the aluminum compound and the strontium compound in the raw material have a molar ratio converted to SrO: Al ₂ O ₃ of 13: 6 to 11: 8 (molar ratio), Or it mix | blends so that it may become a near composition.

  The raw materials are usually prepared in the form of powder (or particles, the same applies hereinafter).

(Step S120)
Next, the raw material is heat treated (hereinafter referred to as “calcined powder preparation heat treatment”). Thereby, calcined powder is prepared.

Here, "calcined powder"
(I) a powder comprising strontium aluminate,
(Ii) a powder containing aluminum oxide and strontium oxide, or (iii) a powder containing at least one of aluminum oxide and strontium oxide and strontium aluminate,
Means either.

  The conditions for the calcined powder preparation heat treatment are not particularly limited as long as the calcined powder can be prepared from the raw materials. For example, the calcined powder preparation heat treatment may be performed in air or an oxygen-containing atmosphere (for example, oxygen gas atmosphere), a vacuum atmosphere, or an inert gas atmosphere.

  For example, the temperature of the calcined powder preparation heat treatment is in the range of 900 ° C to 1650 ° C. Preferably, it is 1000 to 1600 ° C, more preferably 1100 to 1550 ° C, still more preferably 1200 to 1500 ° C, and particularly preferably 1300 to 1450 ° C.

  In addition, although the time of calcining powder preparation heat processing changes also with heat processing temperature, it is the range of 2 hours-48 hours, for example. Preferably, it is 4 hours to 36 hours, more preferably 6 hours to 24 hours, still more preferably 8 hours to 18 hours, and particularly preferably 10 hours to 15 hours.

  The calcined powder obtained by the calcined powder preparation heat treatment is usually a powder or lump that is partially sintered. For this reason, you may implement a grinding | pulverization process as needed.

For the pulverization process (coarse pulverization), for example, a ball mill or the like is used. In the dry ball mill, pulverization may be performed until the average particle size is about 1 μm to 100 μm. In a dry ball mill, for example, alcohol (for example, isopropyl alcohol) represented by C _n H _{2n + 1} OH (n is an integer of 3 or more) is used as a grinding aid. Here, “average particle diameter” means a value obtained by measurement by a laser diffraction scattering method. Hereinafter, the average particle diameter of the powder means a value measured by the same method.

In order to obtain a finer and more uniform powder, for example, a wet ball mill or a circulating bead mill using an alcohol (for example, isopropyl alcohol) represented by C _n H _{2n + 1} OH (n is an integer of 3 or more) as a solvent. Etc. may be used. In this case, the average particle size of the powder can be reduced to 0.5 μm to 50 μm.

(Step S130)
Next, the to-be-processed object containing the calcined powder obtained by above-mentioned step S120 is heat-processed in a load application state. Hereinafter, this process is referred to as “pressure heat treatment (process)”.

  The object to be processed is prepared by adding a halogen compound to the calcined powder obtained in step S120.

  Examples of the halogen compound include, but are not limited to, inorganic halogen compounds (for example, strontium halide compounds and aluminum halide compounds).

  Examples of the strontium halide compound include strontium chloride, strontium fluoride, strontium bromide, strontium iodide, strontium chloride fluoride, and strontium halide hydrate. Examples of the aluminum halide compound include aluminum chloride, aluminum fluoride, aluminum bromide, aluminum iodide, aluminum chlorofluoride, and aluminum halide compound hydrate. In these, strontium chloride and its hydrate, and strontium fluoride are preferable.

  Note that the halogen compound is not necessarily limited to one substance, and the halogen compound may be a plurality of substances. In addition, the halogen compound is not necessarily limited to a substance containing one halogen, and the halogen compound is selected from fluorine (F), chlorine (Cl), bromine (Br), and iodine (I). Halogen may be included.

  The amount of the halogen compound is adjusted so that halide ions contained in the cage are in the range of 50 mol% to 100 mol% in the S12A7 compound. The amount of the halogen compound is preferably 60 mol% to 100 mol%, more preferably 70 mol% to 100 mol%, more preferably 80 mol% to 100 mol%, particularly preferably 90 mol% to 100 mol%.

  The halogen compound powder is not necessarily added in this step. For example, a halogen compound powder may be added when the calcined powder is pulverized in step S120.

  The halogen compound is usually prepared in the form of a powder. It should be noted that the S12A7 compound cannot be manufactured when the object to be processed does not contain a halogen compound.

  Further, the object to be processed may further include a non-conductive S12A7 compound powder. The method for preparing the nonconductive S12A7 compound will be described later.

  The amount of non-conductive S12A7 compound powder added is not particularly limited. For example, the weight ratio of calcined powder (+ halogen compound): non-conductive S12A7 compound powder was in the range of 100: 0 to 10:90. May be.

  However, when the proportion of the non-conductive S12A7 compound is high, the electron density of the conductive S12A7 compound becomes low. Therefore, the amount of the non-conductive S12A7 compound is preferably small. The weight ratio of calcined powder (+ halogen compound): nonconductive S12A7 compound powder is preferably in the range of 100: 0 to 50:50, more preferably in the range of 100: 0 to 70:30. The range of 100: 0 to 90:10 is particularly preferable.

  Note that the non-conductive S12A7 compound powder is not necessarily added in this step. For example, when preparing a mixed raw material containing an aluminum compound and a strontium compound in step S110 described above, a powder of a nonconductive S12A7 compound may be further added. Alternatively, for example, when the calcined powder is pulverized in step S120 described above, powder of a non-conductive S12A7 compound may be further added.

  In this step S130, the calcined powder and the halogen compound react by pressure heat treatment of the object to be processed, and an S12A7 compound containing halide ions in the cage is generated. In addition, some of the halide ions, oxide ions, and / or hydroxide ions in the cage are replaced (reduced) with electrons, and a conductive S12A7 electride compound is formed.

For example, in the first production method, a chloride ion (Cl ⁻ ), a fluoride ion (F ⁻ ), a bromide ion (Br ⁻ ), an iodide ion (I ⁻ ), or at least two or more thereof are contained in the cage. S12A7 electride compounds encapsulating can be produced.

The pressure heat treatment of the object to be processed is performed under a “reducing atmosphere”. “Reducing atmosphere” means a general term for an atmosphere having an oxygen partial pressure in the environment of 10 ⁻³ Pa or less. The “reducing atmosphere” may be an inert gas atmosphere or a reduced pressure environment (for example, a vacuum environment having a pressure of 100 Pa or less). The oxygen partial pressure is preferably 10 ⁻⁵ Pa or less, more preferably 10 ⁻¹⁰ Pa or less, and even more preferably 10 ⁻¹⁵ Pa or less.

  Further, the pressure heat treatment of the object to be processed is performed in an environment where a reducing agent is present. The reducing agent may be, for example, at least one of an aluminum (Al) vapor source, a titanium (Ti) vapor source, a calcium (Ca) vapor source, and a carbon monoxide gas (CO) source.

Among these, the aluminum vapor source may be introduced in the form of, for example, an Al plate, an Al foil, and an Al powder. The titanium vapor source may be introduced in the form of, for example, a Ti plate, a Ti foil, and a Ti powder. The calcium vapor source may be introduced, for example, in the form of CaH ₂ powder. Further, the carbon monoxide gas source may be introduced, for example, by using a carbon (C) member such as a carbon plate and a carbon container.

  Among the above reducing agents, the melting point of aluminum is as low as about 660 ° C., and it becomes liquid during pressure heat treatment and may accumulate in slight gap unevenness. Then, when recovering at room temperature, the S12A7 electride sintered body and carbon or a member containing carbon, which will be described later, are fixed, making it difficult to recover. Accordingly, titanium (Ti), Ca (calcium), and carbon monoxide (CO) are preferable as the reducing agent.

Here, autoclaved of the object is performed in a state where the object to be processed ^and pressurized at a pressure in the range of ^{1kg / cm 2 ~200kg / cm 2} . The pressure to be applied to the object to be processed ^is preferably in the range of ^{10kg / cm 2 ~150kg / cm 2} , more preferably in the range of ^{20kg / cm 2 ~100kg / cm 2} , 30kg / cm 2 ~80kg more preferably in the range of / cm ^2, and particularly preferably in the range of ^{40kg / cm 2 ~60kg / cm 2} .

  Further, the pressure heat treatment of the object to be processed is performed in the range of 1250 ° C to 1480 ° C. The treatment temperature is preferably in the range of 1270 ° C to 1450 ° C, more preferably in the range of 1280 ° C to 1420 ° C, still more preferably in the range of 1290 ° C to 1400 ° C, and 1300 ° C to 1380 ° C. It is particularly preferred that

  The holding time of the object to be processed at a high temperature varies depending on the temperature to be held. For example, the holding time may be in the range of 1 hour to 50 hours. The holding time is preferably in the range of 2 hours to 40 hours, more preferably in the range of 4 hours to 30 hours, further preferably in the range of 6 hours to 20 hours, and 8 hours to 15 hours. It is particularly preferable that the range is

  Thus, when a to-be-processed object is heat-processed in the state which applied the predetermined load, the sintered compact of the S12A7 electride compound which has a comparatively flat surface can be manufactured after heat processing.

  Therefore, in the first production method, a step of post-treating the surface of the obtained S12A7 electride compound after the pressure heat treatment is substantially unnecessary, or an S12A7 electride compound that can be easily processed can be obtained.

  The S12A7 electride compound manufactured by the first manufacturing method is a dense sintered body, and the relative density of the sintered body is, for example, 88% or more. The relative density of the sintered body is preferably 90% or more, more preferably 92% or more, still more preferably 95% or more, and particularly preferably 97% or more. The higher the relative density, the more difficult the sintered body of the S12A7 electride compound is broken against impact and thermal stress. Furthermore, nodules that are black precipitates generated on the surface of the target as the sputtering time elapses are less likely to occur. By reducing the nodules, it is possible to reduce the number of particle adhesion and arcing occurrences on the substrate.

  In the first manufacturing method, a relatively large sintered body of the S12A7 electride compound can also be manufactured without significantly increasing the manufacturing cost.

For example, a sintered body of S12A7 electride compound obtained is a thickness in the range of 5 mm to 50 mm, the area of the main surface may have dimensions ranging 15cm ² ~5000cm ^2.

Furthermore, in the first manufacturing method, a sintered body of a highly conductive S12A7 electride compound having an electron density of 3.0 × 10 ²⁰ cm ⁻³ or more can be obtained relatively easily. In addition, when manufacturing a high electron density S12A7 electride compound, it is preferable that a to-be-processed body does not contain the powder of a nonelectroconductive S12A7 compound.

  FIG. 2 schematically shows a configuration diagram of an apparatus used when the object to be processed is subjected to pressure heat treatment in step S130.

  As shown in FIG. 2, the apparatus 100 includes a pressurizing member 110 and a heating chamber 180.

  The pressure member 110 includes a cylindrical member 120 and a pressing member 130. The cylindrical member 120 and the pressing member 130 are preferably made of carbon, a member containing carbon (for example, SiC), or carbon.

  The cylindrical member 120 has a side surface 122 and a bottom surface 124, and further has an internal space 126 surrounded by the side surface 122 and the bottom surface 124. More specifically, the internal space 126 is partitioned by the inner side wall 128 and the inner bottom wall 129.

  In particular, the cylindrical member 120 may have a substantially columnar or prismatic form. In the former case, the bottom surface 124 is substantially circular, and in the latter case, the bottom surface 124 is substantially polygonal. The internal space 126 may have a substantially cylindrical or prismatic form. In the former case, the inner bottom wall 129 is substantially circular, and in the latter case, the inner bottom wall 129 is substantially polygonal.

  Note that the shape of the bottom surface 124 of the cylindrical member 120 is not necessarily limited to a polygon or a circle, and the shape of the bottom surface 124 is selected in consideration of the shape of the S12A7 electride compound to be manufactured.

  The pressing member 130 has a tip 135, and the tip 135 can be inserted into the internal space 126 of the cylindrical member 120 with a predetermined pressing pressure. FIG. 2 shows a state before the pressing member 130 is inserted into the internal space 126 of the cylindrical member 120.

  In addition, the pressurization member 110 may be comprised with a commercially available hot press apparatus.

  The heating chamber 180 has a structure for accommodating the pressure member 110. The heating chamber 180 has a gas inlet 182 and an exhaust outlet 184, and can control the internal pressure (degree of vacuum) and atmosphere. The heating chamber 180 may have a heating structure that can heat the pressure member 110. For example, a structure including a heating element between the heating chamber 180 and the cylindrical member 120 is assumed. However, when the pressure member 110 itself has a heating mechanism, the heating structure of the heating chamber 180 can be omitted.

  FIG. 3 shows an example of a mode when the apparatus 100 is used.

  As shown in FIG. 3, when using the apparatus 100, first, one or more carbon plates 140 are placed on the lower surface of the internal space 126 of the cylindrical member 120 of the pressure member 110, that is, the inner bottom wall 129. Installed. However, the installation of the carbon plate 140 is arbitrary.

  Next, the first member 142 is installed on the carbon plate 140.

The first member 142 has a reducing agent such as an Al vapor source, a Ti vapor source, and / or a Ca vapor source. For example, the first member 142 may be made of an Al powder, an Al plate, or an Al foil, a Ti powder, a Ti plate, or a Ti foil. Alternatively, the first member 142 may be CaH ₂ powder. Further, the first member 142 may have two or more reducing agents selected from an Al vapor source, a Ti vapor source, and a CaH ₂ powder.

  Next, the target object 145 is installed in the internal space 126 of the cylindrical member 120 so as to cover the first member 142. The object to be processed 145 includes calcined powder and a halogen compound as described above.

  The object to be processed 145 is installed in the internal space 126 in a state (preferably in a state where the whole is covered) covered with, for example, a covering member (for example, alumina (aluminum oxide)) having a large number of fine through holes. May be. In this case, it becomes easy to recover the product after the heat treatment.

  As this covering member, there is a release sheet (for example, cloth, resin, paper, etc. containing ceramic powder). By using the covering member, it is possible to prevent the S12A7 electride compound from adhering to a member such as the first member 142 after step S130.

  Ceramic powders include alumina (aluminum oxide), oxides such as titanium oxide and magnesium oxide, nitrides such as aluminum nitride and titanium nitride, carbides such as silicon carbide and titanium carbide, and borides such as boron nitride. , Hydrides, halides, oxoacids, hydroxides, sulfates, nitrates, carbonates, acetates, metal complexes (coordination compounds), or mixtures thereof can be used.

  Moreover, the release sheet may contain carbon powder in addition to the ceramic powder. The carbon powder may be a powder such as graphite, diamond, or carbon black, or an amorphous powder. The carbon powder may be in the form of whiskers or fibers. A carbon fiber sheet may be used as a release sheet.

  Next, if necessary, the second member 147 is installed in the internal space 126 of the cylindrical member 120 so as to cover the object to be processed 145.

The second member 147 has a reducing agent such as an Al vapor source, a Ti vapor source, and / or a Ca vapor source. For example, the second member 147 may be made of Al powder, Al plate, or Al foil, Ti powder, Ti plate, Ti foil, or the like. Alternatively, the second member 147 may be CaH ₂ powder. The second member 147 may have two or more reducing agents selected from an Al vapor source, a Ti vapor source, and CaH ₂ powder. The second member 147 may be the same member as the first member 142.

  Next, one or more second carbon plates 150 are installed on the second member 147. However, the installation of the second carbon plate 150 is arbitrary.

  Next, the tip 135 of the pressing member 130 is inserted into the internal space 126 of the cylindrical member 120. Further, by applying a load to the pressing member 130 from above, a predetermined pressure is applied to each member in the internal space 126 via the tip 135 of the pressing member 130.

As described above, the pressure applied is in ^the range of ^{1kg / cm 2 ~200kg / cm 2} .

  Next, the assembly 160 including the workpiece 145 configured as described above is installed inside the heating chamber 180.

  Next, the inside of the heating chamber 180 is adjusted to a predetermined pressure and atmosphere using the gas inlet 182 and the exhaust port 184 of the heating chamber 180.

  For example, the inside of the heating chamber 180 can be decompressed by connecting the exhaust port 184 to an exhaust device such as a vacuum pump and operating the exhaust device. Thereafter, a predetermined gas may be introduced at a predetermined concentration via the gas inlet 182.

  Next, the inside of the heating chamber 180 is heated to a predetermined temperature, and the assembly 160 is heated. The heating temperature of the assembly 160 is in the range of 1250 ° C. to 1480 ° C. as described above.

  The heating time varies depending on the processing temperature and the mass of the object to be processed 145, but is, for example, in the range of 1 hour to 50 hours.

  By heating the assembly 160, carbon monoxide gas is generated from the carbon pressure member 110 and the carbon plates 140 and 150.

Further, due to the presence of the first member 142 and the second member 147, the object to be processed 145 is surrounded by a reducing agent such as Ti and / or Ca. For example, when CaH ₂ powder is used for the first member 142 and / or the second member 147, the CaH ₂ powder is decomposed to generate Ca vapor.

  As a result, the inside of the heating chamber 180, particularly the interior space 126 of the cylindrical member 120, has a strong reducing atmosphere. Therefore, an S12A7 electride compound is generated from the object to be processed 145 by the reaction as described above.

  Then, after the assembly 160 is cooled to room temperature, the assembly 160 is taken out from the heating chamber 180 and the product is collected from the assembly 160.

  By performing heat treatment using such an apparatus 100, a sintered body of an S12A7 electride compound having a relatively flat surface can be manufactured from the object to be processed 145.

  It will be apparent to those skilled in the art that the apparatus 100 is merely an example, and the object to be processed may be heat-treated using another apparatus.

(Another production method of S12A7 electride compound according to one embodiment of the present invention)
Next, another method for producing the S12A7 electride compound according to one embodiment of the present invention will be described with reference to FIG.

  FIG. 4 schematically shows an example of another method for producing the S12A7 electride compound (hereinafter simply referred to as “second production method”) according to an embodiment of the present invention.

As shown in FIG. 4, the second manufacturing method is
A step of preparing a raw material, wherein the raw material includes a non-conductive S12A7 compound (step S210);
The object to be processed including the raw ^material, in a state where pressurized at a pressure in the range of ^{1kg / cm 2 ~200kg / cm 2} , under a reducing atmosphere, a step of holding a range of 1250 ℃ ~1480 ℃ (step S220) ,
Have

  Hereinafter, each step will be described in detail.

(Step S210)
First, raw materials are prepared.

  The raw material contains a non-conductive S12A7 compound.

  In addition, a nonelectroconductive S12A7 compound may be prepared by the method as described in patent document 1 (Unexamined-Japanese-Patent No. 2006-160150), for example.

This method
Preparing a mixed powder comprising an aluminum source, a strontium source, and a halogen source (step A);
Heat-treating the mixed powder to synthesize a non-conductive S12A7 compound, wherein a halide ion is included in the cage of the S12A7 compound (step B);
Have

  Hereinafter, Step A to Step B will be briefly described.

(Step A)
First, a mixed powder containing an aluminum source, a strontium source, and a halogen source is prepared.

  For examples of the aluminum source and the strontium source contained in the mixed powder, the aluminum compound and the strontium compound described in step S110 of the first manufacturing method can be referred to. For examples of the halogen source, the halogen compound described in step S130 of the first manufacturing method can be referred to.

(Step B)
Next, the mixed powder is heat-treated (hereinafter referred to as “first heat treatment”). Thereby, a non-conductive S12A7 compound is synthesized.

  The conditions for the first heat treatment are not particularly limited as long as the S12A7 compound having a cage can be formed from the mixed powder. For example, the first heat treatment may be performed in air or an oxygen-containing atmosphere (for example, an oxygen gas atmosphere), a vacuum atmosphere, an inert gas atmosphere, a halogen gas-containing atmosphere, or the like.

Further, the first heat treatment may be performed in a range of 1030 ° C. to 1480 ° C., for example.
Note that when the temperature of the first heat treatment is lower than 1030 ° C., the S12A7 compound having a cage structure may not be formed. Further, if the temperature of the first heat treatment exceeds 1480 ° C., the raw material may be melted. The temperature of the first heat treatment is preferably in the range of 1050 ° C to 1450 ° C, more preferably in the range of 1080 ° C to 1420 ° C, still more preferably in the range of 1100 ° C to 1400 ° C. It is more preferable that the temperature is in the range of 1 ° C to 1380 ° C, and it is particularly preferable to be in the range of 1140 ° C to 1350 ° C.

  The maximum temperature holding time of the first heat treatment may be performed, for example, for 10 minutes to 60 hours. For example, the first heat treatment is performed for 1 hour to 48 hours, preferably 2 hours to 36 hours, more preferably 3 hours to 24 hours, still more preferably 4 hours to 18 hours, particularly preferably 5 hours to 12 hours. May be.

  The temperature and time of the first heat treatment are preferably conditions that allow the S12A7 compound to be easily synthesized and pulverized. A more homogeneous S12A7 electride compound can be obtained by once solidifying the S12A7 compound after grinding.

  By the first heat treatment, halide ions can be included in the cage of the S12A7 compound.

  Note that the non-conductive S12A7 compound obtained in this step may be in a sintered state. In that case, the non-conductive S12A7 compound may be pulverized and powdered.

  By the above method, a nonconductive S12A7 compound can be prepared.

(Step S220)
Next, the raw material containing the non-conductive S12A7 compound obtained in step S210 described above is used as an object to be processed, and is heat-treated with a load applied (pressure heat treatment step). The object to be processed may be the raw material itself obtained in step S210.

  The conditions for the pressure heat treatment of the object to be processed are the same as those in the first manufacturing method described above. Also in the second manufacturing method, the apparatus 100 shown in FIGS. 2 and 3 can be used.

  By this step S220, a conductive S12A7 electride compound is formed from the nonconductive S12A7 compound.

  Also in the second manufacturing method, a sintered body of the S12A7 electride compound having a relatively flat surface can be manufactured after the pressure heat treatment.

  Therefore, in the second production method, after the pressure heat treatment, a step of post-treating the surface of the obtained S12A7 electride compound is substantially unnecessary, or an S12A7 electride compound that can be easily processed can be obtained.

(S12A7 electride compound sintered body according to one embodiment of the present invention)
Next, the sintered body of the S12A7 electride compound according to one embodiment of the present invention will be described.

The sintered body of the S12A7 electride compound according to one embodiment of the present invention (hereinafter referred to as “first sintered body”)
The electron density is 3 × 10 ²⁰ cm ⁻³ or more, the thickness is 5 mm or more,
The area of the main surface is 15 cm ² or more,
The main surface has a feature that the flatness is 3 mm or less.

  Here, the “main surface” of the first sintered body means a surface having the largest area among the surfaces of the first sintered body as described above.

  The thickness of the first sintered body is in the range of 5 mm to 50 mm, preferably in the range of 6 mm to 40 mm, more preferably in the range of 7 mm to 30 mm, and in the range of 8 mm to 20 mm. Is more preferable, and the range of 9 mm to 15 mm is particularly preferable.

The area of the main surface of the first sintered body ^is in the range of 15cm ² ~5000cm ^2, preferably in the range of 20cm ² ~4000cm ^2, more in the range of 30cm ² ~3000cm 2 ^preferably, more preferably in a range of 40cm ² ~2000cm ^2, particularly preferably in the range of 50cm ² ~1000cm 2.

  Further, the flatness of the main surface of the first sintered body is 3.0 mm or less, preferably 1.0 mm or less, more preferably 0.6 mm or less, and 0.3 mm or less. More preferably, it is particularly preferably 0.1 mm or less.

The electron density of the first sintered body is in the range of 3.0 × 10 ²⁰ cm ⁻³ or more, preferably in the range of 8.0 × 10 ²⁰ cm ⁻³ or more, and 1.0 × More preferably, it is in the range of 10 ²¹ cm ⁻³ or more, more preferably in the range of 1.2 × 10 ²¹ cm ⁻³ or more, and in the range of 1.4 × 10 ²¹ cm ⁻³ or more. Particularly preferred.

  Such a 1st sintered compact can be manufactured by the above-mentioned 1st manufacturing method or 2nd manufacturing method, for example.

  As described above, in the conventional method for producing an S12A7 electride compound, the surface of the obtained sintered body does not have very good flatness. For this reason, the post-process for planarizing the surface is normally needed with respect to the obtained sintered compact.

  On the other hand, the first sintered body has a feature that it has a relatively flat surface although it has a relatively large size. Therefore, the first sintered body can be used as it is or by performing a slight processing.

  Examples of the present invention will be described below. Here, Examples 1 to 17 are examples, and examples 51 and 52 are comparative examples.

(Example 1)
The S12A7 electride compound was manufactured by the following method.

(Preparation of calcined powder)
First, 1528.3 g of strontium carbonate (SrCO ₃ , manufactured by Kanto Chemical Co., Ltd., special grade) powder and aluminum oxide so that the molar ratio of strontium oxide (SrO): aluminum oxide (Al ₂ O ₃ ) is 12: 7. (Α-Al ₂ O ₃ , manufactured by Kanto Chemical Co., Ltd., special grade) 671.7 g of powder was mixed.

  Next, this mixed powder was heated to 1400 ° C. at a temperature rising rate of 300 ° C./hour in the atmosphere and held at 1400 ° C. for 12 hours. Thereafter, the temperature was lowered to room temperature at a cooling rate of 300 ° C./hour. As a result, about 1729 g of a bulk product was obtained.

  The obtained product was pulverized to obtain a powder (hereinafter referred to as “calcined powder A1”). When the particle size of the obtained calcined powder A1 was measured by a laser diffraction scattering method (SALD-2100, manufactured by Shimadzu Corporation), the average particle size was 10 μm.

Next, 116.8 g of strontium fluoride (SrF ₂ , manufactured by Junsei Chemical Co., Ltd.) was added to 1723.2 g of calcined powder A1 to obtain a mixed powder. This mixed powder, 3 kg of zirconia balls having a diameter of 5 mm, and 1 ml of industrial EL grade isopropyl alcohol as a grinding aid were placed in a 7 liter zirconia container. Further, after placing a zirconia lid on the container, ball milling was performed at a rotational speed of 72 rpm for 10 hours.

As a result, a white powder (hereinafter referred to as “powder B1”) was obtained. As a result of X-ray diffraction analysis, it was confirmed that the obtained powder B1 contained strontium aluminate (SrO.Al ₂ O ₃ , 3SrO.Al ₂ O ₃ ) and strontium fluoride (SrF ₂ ). Moreover, it turned out that the average particle diameter of powder B1 obtained by the above-mentioned laser diffraction scattering method is 2.0 micrometers.

(Production of S12A7 electride compound)
Next, powder B1 was heat-treated to produce an S12A7 electride compound.

  The apparatus 100 as shown in FIG. 2 was used for the heat treatment of the powder B1. The inner bottom wall 129 of the tubular member 120 is circular and has a diameter of about 60 mm.

In the internal space 126 of the cylindrical member 120, each member was installed from the bottom in the following order:
Two carbon plates 140 (diameter 59mm x thickness 5mm)
Alumina cloth (cloth containing about 50 wt% alumina powder) (MA-80, manufactured by Tanaka Paper Industries Co., Ltd.)
Ti plate as the first member 142 (diameter 59 mm × thickness 0.5 mm)
Powder B1 (60 g) as the object to be processed 145; the powder B1 is a Ti plate (diameter 59 mm × thickness 0.5 mm) as the second member 147 arranged in a state covered with the alumina cloth.
Alumina cloth (cloth containing about 50 wt% alumina powder) (MA-80, manufactured by Tanaka Paper Industries Co., Ltd.)
Four carbon plates 150 (diameter 59 mm × thickness 5 mm).

Next, the assembly was placed in the heating chamber 180 in a state where a pressing pressure of 50 kg / cm ² was applied to the tubular member 120 by the pressing member 130.

  The inside of the heating chamber 180 was depressurized to about 10 Pa by a rotary pump. In this state, the inside of the heating chamber 180 was heated and the heat treatment of the powder B1 was performed.

  The heat treatment was performed by heating the assembly to 1320 ° C. at a rate of temperature increase of 300 ° C./hour, holding at this temperature for 12 hours, and then cooling the assembly to room temperature at a temperature decrease rate of 300 ° C./hour. .

The press pressure was reduced to 0 kg / cm ² immediately after holding at 1320 ° C. for 12 hours.

  When the object to be treated was collected after this treatment, a black material having a black surface (hereinafter referred to as “black material C1”) was obtained. The black material C1 did not adhere to other members and was collected relatively easily.

  In the black material C1, no deformation such as warping or swelling was observed, and the dimensions were a diameter of 60 mm and a thickness of 6.2 mm. The flatness of the main surface (surface with a diameter of 60 mm) was 0.1 mm or less. Further, the relative density of the black material C1 was 95.0%, and the variation depending on the location was 1% or less.

(Evaluation)
A sample was taken from the black material C1. A sample was obtained by roughly pulverizing the black material C1 using an automatic mortar made of alumina, and collecting the obtained coarse powder from a portion corresponding to the central portion of the black material C1.

  X-ray diffraction analysis was performed using the obtained sample. The results are shown in FIG.

As shown in FIG. 5, this sample was found to have an S12A7 structure. Moreover, the electron density calculated | required from the peak position of a light diffuse reflection spectrum was 1.4 * 10 < ²¹ > cm <^-3> , and the variation by a place was not remarkable.

  Thus, a high electron density S12A7 electride compound having good flatness was produced.

(Example 2)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 2, the heat treatment time was set to 24 hours in the above-described step (manufacture of S12A7 electride compound). Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as “black material C2”) was obtained. The black material C2 did not adhere to other members and was collected relatively easily.

  In the black material C2, no deformation such as warping or swelling was observed, and the dimensions were a diameter of 60 mm and a thickness of 6.2 mm. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C2 has an S12A7 structure. Moreover, the relative density of the black material C2 was 96.4%, and the electron density was 1.3 × 10 ²¹ cm ⁻³ .

(Example 3)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 3, the heat treatment time was set to 2 hours in the above-described step (manufacture of S12A7 electride compound). Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as “black material C3”) was obtained. The black material C3 did not adhere to other members and was collected relatively easily.

  In the black material C3, no deformation such as warping or blistering was observed, and the dimensions were a diameter of 60 mm and a thickness of 6.4 mm. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C3 has an S12A7 structure. Moreover, the relative density of the black material C3 was 88.1%, and the electron density was 1.0 × 10 ²¹ cm ⁻³ .

(Example 4)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 4, the heat treatment temperature was set to 1280 ° C. in the above-described step (manufacturing the S12A7 electride compound). Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as “black material C4”) was obtained. The black material C4 did not adhere to other members and was collected relatively easily.

  In the black material C4, no deformation such as warping or blistering was observed, and the dimensions were a diameter of 60 mm and a thickness of 6.6 mm. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C4 has an S12A7 structure. Moreover, the relative density of the black material C4 was 91.4%, and the electron density was 9.8 × 10 ²⁰ cm ⁻³ .

(Example 5)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

However, in Example 5, the press pressure was set to 10 kg / cm ² in the above-described step (manufacture of S12A7 electride compound). Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as “black material C5”) was obtained. The black material C5 did not adhere to other members and was collected relatively easily.

  In the black material C5, no deformation such as warping or swelling was observed, and the dimensions were 60 mm diameter × 6.3 mm thickness. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C5 has an S12A7 structure. Moreover, the relative density of the black material C5 was 94.1%, and the electron density was 1.7 × 10 ²¹ cm ⁻³ .

(Example 6)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

However, in Example 5, the press pressure was set to 100 kg / cm ² in the above-described step (manufacture of S12A7 electride compound). Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as “black material C6”) was obtained. The black material C6 did not adhere to other members and was collected relatively easily.

  In the black material C6, no deformation such as warping or blistering was observed, and the size was 60 mm diameter × 6.0 mm thickness. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C6 has an S12A7 structure. In addition, the relative density of the black material C6 was 97.4%, and the electron density was 1.5 × 10 ²¹ cm ⁻³ .

(Example 7)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

However, in Example 7, in the above-described step (manufacture of S12A7 electride compound), the amount of the object to be processed (powder B1) was 90 g, the thickness of the Ti plate was 1.0 mm, and the press pressure was 100 kg / cm ² and the heat treatment time was 24 hours. Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as “black material C7”) was obtained. The black material C7 did not adhere to other members and was collected relatively easily.

  In the black material C7, no deformation such as warping or blistering was observed, and the dimensions were a diameter of 60 mm and a thickness of 9.0 mm. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C7 has an S12A7 structure. Moreover, the relative density of the black material C7 was 96.2%, and the electron density was 1.2 × 10 ²¹ cm ⁻³ .

(Example 8)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 8, the heat treatment was performed without using the Ti plate in the above-described step (manufacture of S12A7 electride compound). Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as “black material C8”) was obtained. The black material C8 did not adhere to other members and was collected relatively easily.

  In the black material C8, no deformation such as warping or blistering was observed, and the dimensions were 60 mm diameter × 6.3 mm thickness. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C8 has an S12A7 structure. Further, the relative density of the black material C8 was 92.2%, and the electron density was 3.3 × 10 ²⁰ cm ⁻³ .

(Example 9)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 9, the following method was performed.

(Production of S12A7 electride compound)
Powder B1 was heat-treated to produce an S12A7 electride compound.

  The apparatus 100 as shown in FIG. 2 was used for the heat treatment of the powder B1. The inner bottom wall 129 of the tubular member 120 is circular and has a dimension of about 60 mm in diameter.

In the internal space 126 of the cylindrical member 120, each member was installed from the bottom in the following order:
Two carbon plates 140 (diameter 60mm x thickness 5mm)
Alumina cloth 0.45 g CaH ₂ powder layer Ti plate (diameter 59 mm x thickness 0.5 mm)
Powder B1 (60 g) as the object to be processed 145; the powder B1 is disposed in a state of being covered with the alumina cloth Ti plate (diameter 59 mm × thickness 0.5 mm)
0.45 g CaH ₂ powder layer Alumina cloth Two carbon plates 150 (diameter 60 mm × thickness 5 mm).

Next, the assembly was placed in the heating chamber 180 in a state where a pressing pressure of 50 kg / cm ² was applied to the obtained cylindrical member 120 by the pressing member 130.

  The inside of the heating chamber 180 was depressurized to about 10 Pa by a rotary pump. In this state, the inside of the heating chamber 180 was heated and the heat treatment of the powder B1 was performed.

  The heat treatment was performed by heating the assembly to 1340 ° C. at a heating rate of 300 ° C./hour, holding at this temperature for 12 hours, and then cooling the assembly to room temperature at a cooling rate of 300 ° C./hour. .

The press pressure was reduced to 0 kg / cm ² immediately after holding at 1340 ° C. for 12 hours.

  After the heat treatment, a black material (hereinafter referred to as “black material C9”) was obtained. The black material C9 did not adhere to other members and was collected relatively easily.

  In the black material C9, no deformation such as warping or blistering was observed, and the dimensions were a diameter of 60 mm and a thickness of 6.5 mm. The flatness of the main surface (surface with a diameter of 60 mm) was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C9 has an S12A7 structure. Moreover, the relative density of the black material C9 was 94.0%, and the electron density was 1.6 × 10 ²¹ cm ⁻³ .

(Example 10)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 10, the following method was performed.

(Preparation of powder B10)
First, 244.5 g of strontium carbonate (SrCO ₃ , manufactured by Kanto Chemical Co., Ltd., special grade) powder so that the molar ratio of strontium oxide (SrO): aluminum oxide (Al ₂ O ₃ ) is 11.2: 6.8. Then, 105.5 g of aluminum oxide (α-Al ₂ O ₃ , manufactured by Kanto Chemical Co., Ltd., special grade) powder was mixed.

  Next, this mixed powder was heated to 1400 ° C. at a temperature rising rate of 300 ° C./hour in the atmosphere and held at 1400 ° C. for 12 hours. Thereafter, the temperature was lowered to room temperature at a cooling rate of 300 ° C./hour. As a result, about 275 g of a bulk product was obtained.

  The obtained product was pulverized to obtain a powder (hereinafter referred to as “calcined powder A10”). When the particle size of the obtained calcined powder A10 was measured by a laser diffraction scattering method (SALD-2100, manufactured by Shimadzu Corporation), the average particle size was 10 μm.

Next, 14.2 g of strontium fluoride (SrF ₂ , manufactured by Junsei Chemical Co., Ltd.) powder was added to 265.8 g of calcined powder A10 to obtain a mixed powder. This mixed powder, 2 kg of zirconia balls having a diameter of 5 mm, and 1 ml of industrial EL grade isopropyl alcohol as a grinding aid were placed in a 7 liter zirconia container. Further, after placing a zirconia lid on the container, ball milling was performed at a rotational speed of 72 rpm for 20 hours.

As a result, a white powder (hereinafter referred to as “powder B10”) was obtained. As a result of X-ray diffraction analysis, it was confirmed that the obtained powder B10 contained strontium aluminate and strontium fluoride (SrF ₂ ). Moreover, it turned out that the average particle diameter of powder B10 obtained by the above-mentioned laser diffraction scattering method is 2.0 micrometers.

  Next, the step (production of S12A7 electride compound) shown in Example 1 was performed.

  After the heat treatment, a black material (hereinafter referred to as “black material C10”) was obtained. The black material C10 did not adhere to other members and was collected relatively easily.

  In the black material C10, no deformation such as warping or swelling was observed, and the dimensions were 60 mm diameter × 6.5 mm thickness. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C10 has an S12A7 structure. Moreover, the relative density of the black material C10 was about 89.4%, and the electron density was about 1.0 × 10 ²¹ cm ⁻³ .

(Example 11)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 11, S12A7 compound powder prepared by the following method was used as the object to be treated.

(Preparation of powder B11)
First, strontium carbonate (manufactured by Kanto Chemical Co., Ltd., special grade) so that strontium carbonate (SrCO ₃ ): strontium fluoride (SrF ₂ ): aluminum oxide (Al ₂ O ₃ ) has a molar ratio of 11: 1: 7. 164.8 g of powder, 12.8 g of strontium fluoride (manufactured by Junsei Kagaku) powder, and 72.4 g of aluminum oxide (α-Al ₂ O ₃ , Kanto Chemical Co., Ltd., special grade) powder were mixed.

  Next, this mixed powder was heated to 1330 ° C. at a temperature rising rate of 300 ° C./hour in the atmosphere and held at 1330 ° C. for 6 hours. Thereafter, the temperature was lowered to room temperature at a cooling rate of 300 ° C./hour. As a result, about 195 g of a bulk product was obtained.

  The obtained product was pulverized to obtain a powder (hereinafter referred to as “powder A11”). When the particle size of the obtained powder A11 was measured by a laser diffraction scattering method (SALD-2100, manufactured by Shimadzu Corporation), the average particle size was 10 μm.

  Next, 190 g of powder A11, 2 kg of zirconia balls having a diameter of 5 mm, and 1 ml of industrial EL grade isopropyl alcohol as a grinding aid were placed in a 7 liter zirconia container. Further, after placing a zirconia lid on the container, ball milling was performed at a rotational speed of 72 rpm for 20 hours.

As a result, a white powder (hereinafter referred to as “powder B11”) was obtained. As a result of X-ray diffraction analysis, it was found that the obtained powder B11 contained the S12A7 compound as a main crystal and further contained a small amount of SrO.3Al ₂ O ₃ . The S12A7 compound is expected to contain fluoride ions (F ⁻ ) in the cage.

  It was found that the average particle diameter of the powder B11 obtained by the laser diffraction scattering method was 2.0 μm.

  Next, the step (production of S12A7 electride compound) shown in Example 1 was performed.

  After the heat treatment, a black material (hereinafter referred to as “black material C11”) was obtained. The black material C11 did not adhere to other members and was collected relatively easily.

  In the black material C11, deformation such as warping and swelling was not observed, and the dimensions were a diameter of 60 mm and a thickness of 6.1 mm. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C11 has an S12A7 structure. Moreover, the relative density of the black material C11 was about 92.4%, and the electron density was about 1.0 × 10 ²¹ cm ⁻³ .

(Example 12)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 12, an S12A7 electride compound was produced by the following method.

(Preparation of powder B12)
First, the aforementioned powder B1 (100 g) and the aforementioned powder B11 (100 g) were sufficiently mixed. Thereby, powder B12 containing strontium aluminate, strontium fluoride (SrF ₂ ), and the S12A7 compound was obtained.

  Next, using the powder B12 as an object to be processed, the step (manufacture of an S12A7 electride compound) shown in Example 1 was performed.

  After the heat treatment, a black material (hereinafter referred to as “black material C12”) was obtained. The black material C12 did not adhere to other members and was collected relatively easily.

  In the black material C12, no deformation such as warping or blistering was observed, and the dimensions were a diameter of 60 mm and a thickness of 6.0 mm. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C12 has an S12A7 structure. Moreover, the relative density of the black material C12 was 93.5%, and the electron density was 1.0 × 10 ²¹ cm ⁻³ .

(Example 13)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 13, an S12A7 electride compound was produced by the following method.

(Preparation of powder B13)
First, strontium carbonate (SrCO ₃ ): strontium chloride hexahydrate (SrCl ₂ .6H ₂ O): strontium fluoride (SrF ₂ ): aluminum oxide (Al ₂ O ₃ ) in a molar ratio of 11: 0.5 : Strontium carbonate (Kanto Chemical Co., Ltd., special grade) powder 160.2 g, strontium chloride hexahydrate (Kanto Chemical Co., Ltd., special grade) powder 13.5 g, and strontium fluoride 6.2 g of powder (manufactured by Pure Chemical Co., Ltd.) and 70.4 g of aluminum oxide (α-Al ₂ O ₃ , manufactured by Kanto Chemical Co., Ltd., special grade) powder were mixed.

  Next, this mixed powder was heated to 1250 ° C. at a heating rate of 300 ° C./hour in the atmosphere, and held at 1250 ° C. for 12 hours. Thereafter, the temperature was lowered to room temperature at a cooling rate of 300 ° C./hour. As a result, about 193 g of a bulk product was obtained.

  The obtained product was pulverized to obtain a powder (hereinafter referred to as “powder A13”). When the particle size of the obtained powder A14 was measured by a laser diffraction scattering method (SALD-2100, manufactured by Shimadzu Corporation), the average particle size was 10 μm.

  Next, 190 g of powder A13, 2 kg of zirconia balls having a diameter of 5 mm, and 1 ml of industrial EL grade isopropyl alcohol as a grinding aid were placed in a 7 liter zirconia container. Further, after placing a zirconia lid on the container, ball milling was performed at a rotational speed of 72 rpm for 20 hours.

As a result, a white powder (hereinafter referred to as powder “B13”) was obtained. As a result of X-ray diffraction analysis, it was found that the obtained powder B13 contained an S12A7 compound. This S12A7 compound is expected to contain fluoride ions (F ⁻ ) and chloride ions (Cl ⁻ ) in the cage.

  It was found that the average particle size of the powder B13 obtained by the laser diffraction scattering method was 2.0 μm.

  Next, the step (production of S12A7 electride compound) shown in Example 1 was performed.

  However, in Example 13, the heat treatment temperature was set to 1360 ° C. in the above-described step (manufacture of S12A7 electride compound). Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as “black material C13”) was obtained. The black material C13 did not adhere to other members and was collected relatively easily.

  In the black material C13, no deformation such as warping or blistering was observed, and the dimensions were a diameter of 60 mm and a thickness of 6.0 mm. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C13 has an S12A7 structure. Moreover, the relative density of the black material C13 was about 94.9%, and the electron density was 6.4 × 10 ²⁰ cm ⁻³ .

(Example 14)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 14, an S12A7 electride compound was produced by the following method.

(Preparation of powder B14)
First, a 327.8g calcined powder A1 of the foregoing, strontium fluoride of 4.4 g (SrF _2, manufactured by Junsei Chemical Co., Ltd.) powder and, strontium chloride hexahydrate 37.7g _(SrCl 2 _.6H 2 O , Manufactured by Kanto Chemical Co., Ltd., special grade) powder was added to obtain a mixed powder.

  This mixed powder, 3 kg of zirconia balls having a diameter of 5 mm, and 4 ml of industrial EL grade isopropyl alcohol as a grinding aid were placed in a 7 liter zirconia container. Further, after placing a zirconia lid on the container, ball milling was performed at a rotational speed of 72 rpm for 30 hours.

As a result, a white powder (hereinafter referred to as “powder B14”) was obtained. As a result of X-ray diffraction analysis, it was confirmed that the obtained powder B14 was mainly composed of strontium aluminate, strontium fluoride (SrF ₂ ), and strontium chloride hexahydrate (SrCl ₂ .6H ₂ O). It was done. Moreover, it turned out that the average particle diameter of powder B14 obtained by the above-mentioned laser diffraction scattering method is 2.0 micrometers.

  Next, the step (production of S12A7 electride compound) shown in Example 1 was performed.

  However, in Example 14, the heat treatment temperature was 1410 ° C. and the heat treatment time was 6 hours in the above-described step (manufacture of S12A7 electride compound). Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as “black material C14”) was obtained. The black material C14 did not adhere to other members and was collected relatively easily.

  In the black material C14, no deformation such as warping or swelling was observed, and the dimensions were a diameter of 60 mm and a thickness of 5.6 mm. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C14 has an S12A7 structure. Moreover, the relative density of the black material C14 was 93.3%, and the electron density was 9.2 × 10 ²⁰ cm ⁻³ .

(Example 15)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 15, an S12A7 electride compound was produced by the following method.

(Preparation of powder B15)
First, strontium carbonate (SrCO ₃ ): strontium chloride hexahydrate (SrCl ₂ .6H ₂ O): aluminum oxide (Al ₂ O ₃ ) is converted to a molar ratio of strontium carbonate (11: 1: 7). Kanto Chemical Co., Ltd., special grade) powder 155.9 g, strontium chloride hexahydrate (Kanto Chemical Co., Ltd., special grade) powder 25.6 g, aluminum oxide (α-Al ₂ O ₃ , Kanto Chemical Co., Ltd., special grade) 68.5 g of powder was mixed.

  Next, this mixed powder was heated to 1350 ° C. at a temperature rising rate of 300 ° C./hour in the atmosphere and held at 1350 ° C. for 12 hours. Thereafter, the temperature was lowered to room temperature at a cooling rate of 300 ° C./hour. As a result, about 191 g of a bulk product was obtained.

  The obtained product was pulverized to obtain a powder (hereinafter referred to as “powder A16”). When the particle size of the obtained powder A16 was measured by a laser diffraction scattering method (SALD-2100, manufactured by Shimadzu Corporation), the average particle size was 10 μm.

  Next, 190 g of powder A16, 2 kg of zirconia balls having a diameter of 5 mm, and 1 ml of industrial EL grade isopropyl alcohol as a grinding aid were placed in a 7 liter zirconia container. Further, after placing a zirconia lid on the container, ball milling was performed at a rotational speed of 72 rpm for 20 hours.

As a result, a white powder (hereinafter referred to as “powder B15”) was obtained. As a result of X-ray diffraction analysis, it was found that the obtained powder B15 was mainly composed of the S12A7 compound. This S12A7 compound is expected to contain chloride ions (Cl ⁻ ) in the cage.

  It was found that the average particle diameter of the powder B15 obtained by the laser diffraction scattering method was 2.0 μm.

  Next, the step (production of S12A7 electride compound) shown in Example 1 was performed.

  However, in Example 15, the heat treatment temperature was set to 1460 ° C. in the above-described step (manufacturing the S12A7 electride compound). Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as “black material C15”) was obtained. The black material C15 did not adhere to other members and was collected relatively easily.

  In the black material C15, no deformation such as warping or swelling was observed, and the dimensions were a diameter of 60 mm and a thickness of 5.6 mm. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C15 has an S12A7 structure. Moreover, the relative density of the black material C15 was about 94.5%, and the electron density was 1.1 × 10 ²¹ cm ⁻³ .

(Example 16)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 16, an S12A7 electride compound was produced by the following method.

(Preparation of powder B16)
313.5 g of calcium carbonate (CaCO ₃ , manufactured by Kanto Chemical Co., Ltd., special grade) powder and aluminum oxide (α) so that the molar ratio of calcium oxide (CaO): aluminum oxide (Al ₂ O ₃ ) is 12: 7. -Al ₂ O ₃ (manufactured by Kanto Chemical Co., Ltd., special grade) powder 186.5 g was mixed.

  Next, this mixed powder was heated to 1350 ° C. at a temperature rising rate of 300 ° C./hour in the atmosphere and held at 1350 ° C. for 12 hours. Thereafter, the temperature was lowered to room temperature at a cooling rate of 300 ° C./hour. As a result, about 358 g of a bulk product was obtained.

  The obtained product was ball milled as described above to obtain a white powder. As a result of X-ray diffraction analysis, it was found that the obtained white powder contained a C12A7 compound (a compound containing calcium carbonate and aluminum oxide at a molar ratio of 12: 7). The average particle size of the obtained white powder was found to be 2.0 μm by the laser diffraction scattering method described above.

Next, the aforementioned powder B1 (135.5 g) and 64.5 g of white powder were mixed to obtain a mixed powder (hereinafter referred to as “powder B16”). Powder B16 contains strontium aluminate, strontium fluoride (SrF ₂ ), and a C12A7 compound.

  Next, the step (production of S12A7 electride compound) shown in Example 1 was performed.

  However, in this example 16, in the above-mentioned step (manufacture of S12A7 electride compound), the amount of the object to be processed (powder B16) was 50 g, and the heat treatment temperature was 1300 ° C. Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as “black material C16”) was obtained. The black material C16 did not adhere to other members and was collected relatively easily.

  In the black material C16, no deformation such as warping or blistering was observed, and the dimensions were a diameter of 60 mm and a thickness of 7.1 mm. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C16 has an S12A7 structure. Further, the relative density of the black material C16 was 97.5%, and the electron density was 1.7 × 10 ²¹ cm ⁻³ .

In this example, the black material C16 has a crystal structure in which the C12A7 compound is dissolved in the S12A7 compound, that is, in the form of an S9C3A7 electride compound (Sr ₉ Ca ₃ Al ₁₄ O ₃₂ : (F ⁻ , e ⁻ )). Can be expected.

(Example 17)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in Example 17, an S12A7 electride compound was produced by the following method.

(Preparation of powder B17)
313.5 g of calcium carbonate (CaCO ₃ , manufactured by Kanto Chemical Co., Ltd., special grade) powder and aluminum oxide (α) so that the molar ratio of calcium oxide (CaO): aluminum oxide (Al ₂ O ₃ ) is 12: 7. -Al ₂ O ₃ (manufactured by Kanto Chemical Co., Ltd., special grade) powder 186.5 g was mixed.

  Next, this mixed powder was heated to 1000 ° C. at a temperature rising rate of 300 ° C./hour in the atmosphere and held at 1000 ° C. for 12 hours. Thereafter, the temperature was lowered to room temperature at a cooling rate of 300 ° C./hour. As a result, about 358 g of a bulk product was obtained.

The obtained product was ball milled as described above to obtain a white powder. As a result of X-ray diffraction analysis, the obtained white powder was found to contain calcium oxide (CaO), aluminum oxide (Al ₂ O ₃ ), and a slight amount of calcium aluminate. Moreover, it turned out that the average particle diameter of the white powder obtained by the above-mentioned laser diffraction scattering method is 2.0 micrometers.

Next, the aforementioned powder B1 (135.5 g) and 64.5 g of white powder were mixed to obtain a mixed powder (referred to as “powder B17”). This powder B17 contains strontium aluminate, strontium fluoride (SrF ₂ ), calcium oxide (CaO), and aluminum oxide (Al ₂ O ₃ ), and slightly contains calcium aluminate.

  Next, the step (production of S12A7 electride compound) shown in Example 1 was performed.

  However, in Example 17, in the above-described step (manufacture of S12A7 electride compound), the amount of the object to be processed (powder B17) was 50 g, and the heat treatment temperature was 1300 ° C. Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as “black material C17”) was obtained. The black material C17 did not adhere to other members and was collected relatively easily.

  In the black material C17, no deformation such as warping or blistering was observed, and the dimensions were a diameter of 60 mm and a thickness of 7.0 mm. The flatness of the main surface was 0.1 mm or less.

As a result of the evaluation as described above, it was found that the black material C17 has an S12A7 structure. Moreover, the relative density of the black material C17 was 97.4%, and the electron density was 1.7 × 10 ²¹ cm ⁻³ .

In this example, the crystal structure of the black material C17 is a form in which the C12A7 compound is dissolved in the S12A7 compound, that is, the form of the S9C3A7 electride compound (Sr ₉ Ca ₃ Al ₁₄ O ₃₂ : (F ⁻ , e ⁻ )). Can be expected.

  Table 1 below collectively shows the production conditions and evaluation results of the S12A7 electride compounds in Examples 1 to 17.

（例５１）
以下の方法で、Ｓ１２Ａ７エレクトライド化合物を製造した。

(Example 51)
The S12A7 electride compound was manufactured by the following method.

(Production of molded body)
An acrylic binder was added to the aforementioned powder B11 to prepare a paste for a molded body. In addition, this paste was placed thinly on the mold. In this state, the paste was pressurized to prepare a molded body.

  The dimensions of the obtained molded body were length 116 mm × width 116 mm × thickness 7 mm.

(Preparation of S12A7 electride compound)
Next, reduction heat treatment was performed by the following method using the obtained molded body.

  First, the entire surface of the molded body was coated with a commercially available aluminum foil (manufactured by Mitsubishi Aluminum Co., Ltd.) several times to prepare a workpiece. The total thickness of the portion covered with the aluminum foil is 55 μm.

This object to be treated was placed in an alumina container with alumina plates arranged on the top and bottom. An alumina weight (390 g) was placed on the upper alumina plate. Thereby, a load of about 0.004 kg / cm ² was applied to the object to be processed.

  Next, an alumina lid was placed on top of the alumina container. The entire alumina container with a lid was placed in the first carbon container, and a carbon lid was placed on the top. A carbon fiber bundle was disposed on the alumina lid.

  Next, the 1st carbon container with a lid | cover was arrange | positioned in the 2nd carbon container, and the lid | cover made from carbon was arrange | positioned at the upper part. Thereby, the assembly for reductive heat processing was comprised.

  Next, this assembly was installed in an electric furnace capable of adjusting the atmosphere. Moreover, the pressure in the electric furnace was reduced to about 10 Pa using a rotary pump.

  Next, the assembly was heated and a reduction heat treatment was performed on the object to be processed.

  In the reduction heat treatment, the assembly is heated to 1320 ° C. at a temperature rising rate of 300 ° C./hour, held at this temperature for 24 hours, and then cooled to room temperature at a temperature falling rate of 300 ° C./hour. Carried out.

  After the reduction heat treatment, the object to be treated was recovered to obtain a black material C51.

  The rough dimension of the black material C51 was 100 mm × 100 mm × 6.1 mm.

However, the black material C51 was undulated and the flatness of the main surface (100 mm × 100 mm = 100 cm ² surface) was 3.2 mm.

(Example 52)
An S12A7 electride compound was produced in the same manner as in Example 1 above.

  However, in this example 52, the heat treatment temperature was set to 1230 ° C. in the above-described step (manufacture of S12A7 electride compound). Other conditions are the same as in Example 1.

  After the heat treatment, a black material (hereinafter referred to as black material “C52”) was obtained. The black material C52 was not sintered, and a sintered body was not obtained.

DESCRIPTION OF SYMBOLS 100 Apparatus 110 Pressure member 120 Cylindrical member 122 Side surface 124 Bottom surface 126 Internal space 128 Inner side wall 129 Inner bottom wall 130 Pressing member 135 Tip 140 Carbon plate 142 First member 145 Object to be processed 147 Second member 150 Second member Carbon plate 160 Assembly 180 Heating chamber 182 Gas inlet 184 Exhaust outlet

Claims (10)

A method for producing an S12A7 electride compound,
(1-1) preparing a raw material containing an aluminum compound and a strontium compound;
(1-2) A step of heat-treating the raw material to prepare a calcined powder,
(I) a powder comprising strontium aluminate,
(Ii) a powder comprising aluminum oxide and strontium oxide, or (iii) a powder comprising at least one of aluminum oxide and strontium oxide and strontium aluminate,
A step that is either
(1-3) wherein the object to be processed comprising a calcined powder and a halogen ^compound, in a pressurized state at a pressure in the range of ^{1kg / cm 2 ~200kg / cm 2} , under a reducing atmosphere, the 1250 ℃ ~1480 ℃ A process of holding in the range;
A manufacturing method comprising:   The said halogen compound is a manufacturing method of Claim 1 containing a chloride, fluoride, or the combination of both.   The manufacturing method according to claim 1 or 2, wherein the object to be processed further includes an S12A7 compound.   The said raw material is a manufacturing method as described in any one of Claims 1 thru | or 3 which contains a S12A7 compound further. The manufacturing method according to any one of claims 1 to 4, wherein an S12A7 electride compound having an electron density of 3 × 10 ²⁰ cm ^-3 or more is obtained after the step (1-3). A method for producing an S12A7 electride compound,
(2-1) preparing a raw material containing the S12A7 compound;
(2-2) the object to be processed including the raw ^material, in a pressurized state at a pressure in the range of ^{1kg / cm 2 ~200kg / cm 2} , under a reducing atmosphere, a step of holding a range of 1250 ℃ ~1480 ℃ When,
A manufacturing method comprising:   The holding is performed in an environment including at least one of an aluminum (Al) vapor source, a titanium (Ti) vapor source, a calcium (Ca) vapor source, and a carbon monoxide gas (CO) source. Item 7. The manufacturing method according to any one of Items 1 to 6.   The manufacturing method according to claim 1, wherein in the holding step, the object to be processed is pressurized in a carbon pressure member.   The manufacturing method according to claim 1, wherein the holding step is performed by a hot press apparatus. S12A7 electride compound sintered body,
The electron density is 3 × 10 ²⁰ cm ⁻³ or more, the thickness is 5 mm or more,
The sintered body has a main surface,
The area of the main surface is 15 cm ² or more,
The flatness of the said main surface is a sintered compact which is 3 mm or less.

Images