JP2000012308A - Manufacture of thermistor element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a thermistor element such that variations in resistance value are reduced, related to a thermister element of a baked body. SOLUTION: As a precursor compound, triethoxy yttrium, diethoxy manganese, Tris (2,4-pentatieno) chrome are mixed with an ethanol and isopropanol mixture solution for reflux, thus obtaining a composite metal alkoxide solution, and then a pure water which is a metallic salt depositing agent is added for agitation/mixture, and reflux, providing a gel-like precipitate of metallic salt comprising Y, Mn, and Cr. The precipitate is filtered and dried, and then temporarily baked to provide a material powder of composition of 30Y (Cr0.5Mn0.5) O3.62Y2O3 similar to the composition of a thermistor element. After that, the material powder is molded and baked to provided a thermistor element as a baked body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a thermistor element made of a sintered body, and this thermistor element can be detected in a high temperature range from room temperature to 1000.degree. It is suitable for use as a simple thermistor element.

[0002]

2. Description of the Related Art Conventionally, a thermistor element made of a sintered body of this kind has been used in a medium to high temperature range of 400 ° C. to 1300 ° C. for automobile exhaust gas temperature, gas flame temperature of a gas water heater, etc. It is used for a temperature sensor that measures the temperature of the device. As this type of thermistor element, a sintered body composed of a perovskite-based or corundum-based material is mainly used. For example, a thermistor element using a perovskite-based material is described in JP-A-7-201528. Stuff has been proposed. Here, in order to realize a thermistor element that can be used in a wide temperature range,
A plurality of oxide raw materials such as Y, Sr, Cr, Fe, Ti
A thermistor element is obtained by a so-called solid phase method of mixing at a predetermined composition ratio, pulverizing, granulating, and firing.

[0003]

In recent years, a temperature sensor (exhaust gas temperature sensor) for automobile exhaust gas has been proposed.
In order to control the temperature of the exhaust gas before and after the catalyst in order to detect the deterioration of the catalyst for purifying exhaust gas of gasoline vehicles, and to control the temperature of the catalyst for purifying exhaust gas of diesel vehicles, especially NOx gas. There is a great demand for application to systems that detect exhaust temperatures before and after the catalyst.

However, in order to apply to such a system, a temperature sensor using a conventional thermistor element has a large variation in resistance-temperature characteristics (RT characteristics), and its temperature accuracy is, for example, ± 20. ~ 30 ° C (room temperature ~
(600 ° C.), which is insufficient for high-precision system control. Therefore, development of a thermistor element that achieves better temperature accuracy is desired. Then, the present inventors diligently studied a conventional thermistor element in terms of the structure, the manufacturing method, and the like, and as a result, found that there were the following problems to improve the temperature accuracy.

That is, in the solid-phase method, mixing and pulverization of a plurality of oxide raw materials are performed by, for example, a ball mill or the like. However, since the pulverizing ability is not sufficient, the average particle size of the thermistor raw material after mixing and pulverization is obtained. The diameter is limited to 1 to 2 μm, and uniform mixing cannot be obtained. In addition, due to the difference in the average particle diameter of the oxide raw material, the reaction in heat treatment such as preliminary firing and firing does not proceed uniformly, so that the composition of the thermistor raw material generated by the thermal reaction becomes uneven.

Furthermore, in the mixing and pulverizing operations in the above-mentioned ball mill or the like, components such as alumina balls in the pulverizing medium are mixed as impurities into the thermistor raw material to cause a variation in resistance or to reduce the intended composition of the thermistor element. There is also the problem of deviation. Accordingly, the resistance value of the obtained thermistor element has a large variation, and the temperature sensor using this thermistor element has a variation in RT characteristics, resulting in deterioration of temperature accuracy.

Incidentally, at present, the above-mentioned system cannot be realized with the temperature accuracy of a conventional temperature sensor using a thermistor element. Therefore, instead, a thermocouple, a platinum resistor or the like, which has high accuracy but is expensive, is used as the temperature sensor. ing. However, in any case, temperature accuracy (for example, from room temperature to 600 ° C.) at a level applicable to the above-described systems and the like has been hitherto.
There was no temperature sensor using a thermistor element having a temperature of ± 5 ° C.).

In view of the above problems, it is an object of the present invention to provide a method of manufacturing a thermistor element made of a sintered body that reduces variation in the resistance value of the thermistor element.

[0009]

As described above, the present inventors proceeded with the study of each manufacturing process of the thermistor element, from the viewpoint of improving the temperature accuracy of the temperature sensor using the thermistor element. In the method, the uniform mixing of the raw materials cannot be obtained due to the large average particle diameter of the raw materials, and the non-uniform composition after heat treatment such as calcination and firing due to the difference in the average particle diameters is caused by the resistance value of the thermistor element. It has been found that it affects the variation.

As a result of further study, in the thermistor element generated after the thermal reaction in the heat treatment, the composition variation of the crystal phase mainly controlling the resistance value, as a result, the variation in the resistance value of the thermistor element Turned out to affect. Regarding this, a mixed sintered body (mixed fired body) 38Y (Cr _0.5 Mn _0.5 ) O ₃ .62
A case where a thermistor element made of Y ₂ O ₃ is manufactured by a conventional solid phase method will be described as an example.

38Y (Cr _0.5 Mn _0.5 ) O ₃ .62Y
_{In 2} O ₃ , Y ₂ O ₃ (yttria) has a property close to that of an insulator, and the crystal phase (resistance dominant phase) that mainly controls the resistance value is Y (C) having a perovskite structure.
r _0.5 Mn _0.5 ) O ₃ . Therefore, Y (Cr _0.5 M
n _0.5 ) O ₃ composition variation becomes a problem. 38Y (C
r _0.5 Mn _0.5 ) O ₃ .62Y ₂ O ₃ is prepared, for example, as follows (see FIG. 8).

First, in the above-mentioned solid phase method, an oxide raw material is used.
Y_TwoO_Three(Average particle size of about 1 μm (micrometer))
Cr, the raw material of M2_TwoO_Three(Average particle size of about 4 μm) and
Mn _TwoO_Three(Average particle size of about 7μm) as starting material
You. Subsequently, in the compounding process, the final set of thermistor elements
38Y (Cr_0.5Mn_0.5) O_Three・ 62Y_TwoO_ThreeWhen
So that the starting material Y_TwoO_ThreeAnd Cr_TwoO_ThreeAnd Mn_Two
O_ThreeWeigh Then, weigh this material with a ball mill or the like.
Mix and pulverize and mix the starting material mixture at
Fired, 38Y (Cr_0.5Mn_0.5) O_Three・ 62Y_TwoO
_ThreeIs obtained.

The starting materials Y ₂ O ₃ and Cr ₂ O ₃
Y (Cr _0.5 Mn _0.5 ), which is the resistance value dominant phase in the above-mentioned calcined body, has a target composition of crystal grains due to the difference in particle size between the alloy and Mn ₂ O ₃ and the limit of the mixing / crushing ability of a ball mill or the like. A composition deviating from (Y: Cr: Mn = 1: 0.5: 0.5), for example, Y: Cr: Mn = 1: 0.6: 0.
4 from the composition of Y: Cr: Mn = 1: 0.4: 0.
The composition is composed of crystal grains of various compositions up to the composition of No. 6.

These Y: Cr: Mn = 1: 0.6: 0.
4 from the composition of Y: Cr: Mn = 1: 0.4: 0.
Since the composition of No. 6 has different resistance values and different temperature coefficients of resistance (β values), the resistance value fluctuates from element to element and causes variation in element resistance value. The raw material Y ₂ O ₃
If some of the Cr ₂ O ₃ and Mn ₂ O ₃ (which deviates from the composition ratio) remains as unreacted materials has become a cause of variation of the element resistance value.

The variation in the element resistance value due to the above-described composition variation is caused by the fact that Y (Cr _0.5 M
Since n _0.5 ) O ₃ is generated, the same can be said for the case where the composition of the thermistor element is composed of crystal grains such as Y (Cr _0.5 Mn _0.5 ) O ₃ alone. Here, the present inventor thought that in order to reduce the composition variation of the calcined body, it is possible to solve the above-mentioned problems such as the composition variation and the presence of unreacted materials of the raw materials in the process before the preliminary calcining. As a result of various studies, attention was paid to performing mixing of a plurality of raw materials in a liquid phase in a state of a precursor compound which is easily dispersed or dissolved in a solvent, instead of a metal oxide powder, that is, a solid state.

Based on this idea, the above 38Y (Cr _0.5
Mn _0.5 ) O ₃ .62Y ₂ O ₃ , as well as a thermistor element made of various sintered bodies, as a result of repeated experimental studies, using a raw material obtained by adjusting the composition of a precursor compound by a liquid phase method, It was found that by manufacturing the thermistor element, the composition of the crystal particles was made uniform, the resistance value variation was reduced, and the temperature accuracy of the temperature sensor could be improved. Claim 1
The invention according to claim 13 is based on the result of this study.

That is, according to the first aspect of the present invention, a plurality of precursor compounds containing a metal element are mixed in a liquid phase to form a mixed solution, and a metal salt precipitant is added to the mixed solution. A gel-like precipitate of a metal salt containing the metal element was precipitated, and then the precipitate was dried and heated to form a raw material powder that was a powdery composition containing a plurality of metal elements. Thereafter, the raw material powder is fired to obtain a thermistor element as a sintered body.

As a result, the plurality of precursor compounds are dissolved or dispersed in the liquid phase, so that the desired composition can be obtained in the state of being atomized to the order of atoms and molecules without being influenced by the average particle size unlike the solid phase method. The ratio can be mixed, and uniform mixing of each precursor compound can be achieved. Therefore, the composition finally obtained as a powder, that is, the raw material powder, is a mixture of the respective metal elements uniformly in the atomic / molecular order at a desired composition ratio,
Even in the subsequent heat treatment, the thermal reaction can be made uniform.

Therefore, in the thermistor element produced as a sintered body as a result, the composition variation of the crystal particles constituting the thermistor element can be suppressed. And
In the temperature sensor using the thermistor element manufactured by the manufacturing method of the present invention, the temperature accuracy is lower than the conventional level (for example, ± 20 to 30 ° C. from room temperature to 600 ° C.) because the resistance value variation between the elements is small. Good (for example, room temperature to 6
(± 2-5 ° C at 00 ° C).

According to the second aspect of the present invention, in the step of forming a mixed solution, the plurality of precursor compounds have at least two carboxyl groups as coordination sites and at least one other coordination site. Mixed in a liquid phase together with the complex compound to form a mixed solution, in which a plurality of precursor compounds are reacted with the complex compound, and a composite metal in which at least one metal element is coordinated. It is characterized by forming a complex compound.

In the present invention, a mixed solution in which the complex metal complex compound is dissolved or dispersed is formed. Thereafter, similarly to the production method of claim 1, a gel-like precipitate in which the composite metal complex compound or a polymer thereof is a metal salt is obtained, and a raw material powder is obtained from the precipitate. The same effect as the invention can be obtained. Here, ethylenediaminetetraacetic acid (EDTA) or citric acid can be used as the complex compound.

According to the results of studies by the present inventors, the precursor compound is selected from metal alkoxides, metal acetylacetonates, and metal carboxylates as in the invention described in claim 4 or 5. Using one or more organometallic compounds or selecting from nitrate compounds, oxynitrate compounds, chlorides, oxychlorides
It is preferable to use at least one kind of inorganic metal compound.

According to a sixth aspect of the present invention, a plurality of precursor compounds containing a metal element are mixed in a liquid phase to form a mixed solution, and a powder containing the plurality of metal elements is formed from the mixed solution. The method is characterized in that after forming a raw material powder which is a liquid composition, the raw material powder is fired to obtain a thermistor element as a sintered body. Specifically, the present invention can be realized by a physical liquid phase method such as a spray pyrolysis method, a pyrolysis method, a freeze drying method, and a solution combustion method, in addition to the chemical liquid phase method. The same operation and effect as in the method can be obtained.

Here, the thermistor element obtained by the manufacturing method (liquid phase method) according to any one of claims 1 to 6 is a TE element.
As a result of observation with an M (transmission electron microscope), each crystal particle (for example, the above 38Y (Cr _0.5 Mn _0.5 ) O ₃ .62Y
_In the example of ₂ O ₃ , Y (Cr _0.5 Mn _0.5 ) O ₃ and Y ₂ O
_The primary particle size of the (crystal particles ₃ ) is smaller than 1 μm and several nm.
(Nanometer), it was confirmed that the composition was fine particles of several 100 nm and the composition was uniformly dispersed and mixed.

The invention according to claim 7 relates to a temperature sensor using a thermistor element in which the composition variation is suppressed by such atomization. In particular, the invention according to claims 8 to 13 is based on the point that the composition of the precursor compound is prepared by a liquid phase method, and in the composition (M1M2) O ₃ , M1 is a group 2A of the periodic table of elements and La 3A excluding
M2 is at least one element selected from Group III elements, and M2 is Group 3B, Group 4A, or Group 5A of the Periodic Table of the Elements.
And at least one element selected from the group consisting of Group 6A, Group 6A, Group 7A and Group 8 elements, wherein the (M1M2) O
₃ and Y ₂ O ₃ mixed sintered body (M1M2) O ₃ .Y ₂ O
This is applied to a method for manufacturing a thermistor element composed of ( ₃ ).

That is, in the manufacturing method according to claim 8,
Are the multiple elements containing the elements that make up the thermistor element.
A mixed solution in which a precursor compound and a complexing agent are mixed in a liquid phase.
To form the plurality of precursor compounds and the plurality of precursor compounds in the mixed solution.
Reacting with a complexing agent to form a complex complex compound,
To form a polymer by adding a polymerizing agent to the complex complex compound.
The polymer is dried and heat-treated to obtain a thermistor.
Raw material powder containing the elements constituting the star element is obtained,
Baking powder and mixing sintered body (M1M2) O_Three・ Y_TwoO _ThreeWhen
Is obtained.

As a result, the plurality of precursor compounds are dissolved or dispersed in the liquid phase, so that the same effects as those of the manufacturing method of claim 1 are obtained. As a result, the thermistor element manufactured as a mixed sintered body has the following advantages. Variations in the composition of crystal grains constituting the thermistor element can be suppressed. The temperature sensor using the thermistor element manufactured by the present manufacturing method has a small variation in resistance value between elements, so that the temperature accuracy is higher than a conventional level (for example, ± 20 to 30 ° C. from room temperature to 600 ° C.). Good (for example, room temperature to 6
(± 1.5-5 ° C at 00 ° C).

Further, in the manufacturing method according to the ninth aspect, citric acid is used as a complexing agent and ethylene glycol is used as a polymerizing agent, and the number of moles of citric acid is a, and the total number of moles of elements constituting the thermistor element is b. Where 1 ≦
It is characterized by satisfying the relationship of a / b ≦ 30.
According to the present production method, in the step of forming a complex complex compound, a complexation reaction in which ions of the elements constituting the thermistor element are coordinated in the coordination site of citric acid in the liquid phase,
Form a complex complex compound. Thereafter, the composite complex compound and the polymerizing agent are mixed with ethylene glycol and reacted by heating to obtain a polymer, from which raw material powder is obtained.

Further, according to the study by the present inventors, it has been found that by increasing the concentration of citric acid added to obtain the above complex complex compound, the composition becomes more uniform. That is, by setting the concentration of citric acid in the range described in claim 9, a thermistor element having good temperature accuracy can be obtained. If the concentration of citric acid is more than 30 times the equivalent (concentration of 30 times the total number of moles of the elements constituting the thermistor element), an association / aggregation phenomenon between citric acids occurs, and the polymer obtained thereafter becomes colloidal. Since the sol particles are in the form of a sol and some of the constituent elements of the thermistor element are dissociated in the liquid phase, a new problem such as a composition deviation occurs. Therefore, it is preferable to select the citric acid concentration in a range up to 30 times the equivalent.

The invention according to claims 10 to 12 is based on the fact that the present inventors have independently determined the composition of a thermistor element used for a temperature sensor capable of measuring a wide temperature range, that is, a so-called wide-range thermistor element. As a result of the examination, it is possible to obtain a thermistor element that is determined and can be measured in a wide temperature range from room temperature to 1000 ° C.

The invention according to claim 13 is the invention according to claim 8
The present invention relates to a temperature sensor using a thermistor element manufactured by the manufacturing method according to the twelfth aspect, realizing uniform composition, and having good temperature accuracy.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A thermistor element according to the present embodiment is applied to a thermistor element (so-called wide-range thermistor element) used for a temperature sensor capable of measuring a wide temperature range from room temperature to 1000 ° C. It has been done. The temperature sensor using the thermistor element of the present embodiment can be used, for example, as a temperature sensor for detecting the temperature of automobile exhaust gas.

FIG. 1 shows the thermistor element 1 of this embodiment.
It is a block diagram. The thermistor element 1 is a bulk of a predetermined shape.
(In this example, a cylindrical body). this
The thermistor element 1 is made of a sintered body, and includes Y, Sr, Cr,
A plurality of metals such as Fe and Ti were blended at a predetermined composition ratio
It is an oxide. Specifically, aY (Cr_0.5Mn_0.5)
O_Three・ BY_TwoO_Three, AY (Cr_0.5Mn_0.5) O_Three・ B
Al_TwoO_Three, (Y_0.9Ca_0.1) (Cr_0.75Fe_0.2T
i_0.05) O_Three, (Al_0.7Cr_0.2Fe_0.1) _TwoO_Three・
It can be a composition such as MgO.CaO.

In FIG. 1, reference numerals 11 and 12 denote a pair of lead wires (signal extraction electrodes) made of platinum or the like for detecting the temperature from the resistance change of the thermistor element 1. Although not shown, the two lead wires 11 and 12 are buried in the thermistor element 1 at a certain interval substantially in parallel with the cylindrical axis direction of the thermistor element 1. The portion other than the buried portion is drawn out to one end side of the thermistor element 1.

Then, as shown in FIG. 2, the thermistor element 1 provided with the lead wires 11 and 12 is connected to the temperature sensor 10.
0 is incorporated. FIG. 2 is a sectional view of the temperature sensor 100, and FIG. 3 is a sectional view taken along line AA of FIG. Here, 2 is a bottomed cylindrical metal cap, and 3 is a cylindrical metal pipe. The metal cap 2 is fixed to the outer periphery of the metal pipe 3 by caulking or the like, and the inside of the metal cap 2 is a closed space. The thermistor element 1 provided with the lead wires 11 and 12 is disposed inside the metal cap 2.

The ends of the lead wires 11 and 12 on the lead-out side are connected to an external circuit (not shown) (for example, an ECU of an automobile).
31 and 32 for exchanging signals with etc.
Is electrically connected to Both lead wires 11, 12, 3
The connection portions of the first and the second 32 may be inside or outside the metal pipe 3. As shown in FIG. 3, the inside of the metal pipe 3 is filled with magnesia powder 33, and the insulation of the lead wires 31 and 32 in the metal pipe 3 is ensured.

The temperature sensor 100 is provided with the tip of the metal cap 2 in an exhaust gas passage of an automobile exhaust gas device or the like, and can detect the temperature of the exhaust gas. Specifically, the exhaust gas temperature can be obtained by extracting the temperature of the exhaust gas as an electric signal from each of the lead wires 11, 1231, and 32 to the external circuit by using the RT characteristic of the thermistor element 1.

Next, a method of manufacturing the thermistor element 1 will be described. The details will be described in the embodiments described later. The production method of the present embodiment is roughly divided into a first step (raw material powder production step) until a raw material powder containing a metal element constituting the thermistor element 1 in a desired composition is obtained by a liquid phase method,
Granulation, drying, molding, baking and the like are performed using the obtained raw material powder, and the process is divided into a second step (thermistor molding step) until the thermistor element 1 is obtained.

First, in a first step, a plurality of precursor compounds containing a metal element constituting the thermistor element 1 are mixed in a liquid phase so as to have a desired composition to form a mixed solution. A powdery composition containing a plurality of metal elements by adding a metal salt precipitant to the mixture to precipitate a gel precipitate of a metal salt containing a plurality of metal elements, and drying and heating the precipitate. Is formed.

Here, as the precursor compound, an organometallic compound such as a metal alkoxide, a metal acetylacetonate, or a metal carboxylate can be used. For example, triethoxy yttrium (Y (OC
₂ H ₅ ) ₃ ), diethoxymanganese (Mn (OC
₂ H _5)), tris (2,4-Pentajiono) Chromium (Cr [OC (CH ₃₎ CHCOCH _{3] 3),} and the like.

As the precursor compound, inorganic metal compounds such as nitrate compounds, oxynitrate compounds, chlorides and oxychlorides can also be used. For example, yttrium nitrate (Y (NO ₃ ) ₃ .6H ₂ O) ), calcium nitrate _{(Ca (NO 3) 3 ·} 4H 2 O), chromium nitrate (Cr
_{(NO 3) 3 · 9H 2} O), iron nitrate (Fe (NO _{3) 3}
.9H ₂ O), titanium oxynitrate (5TiO _{2.
N 2 O 5 · 6H 2 O} ) and the like.

The solvent for dissolving or dispersing these precursor compounds is selected in consideration of solubility, post-treatment (drying, etc.), and for example, an organic solvent such as a mixed solution of ethanol and isopropanol, or pure water. Etc. can be used. The metal salt precipitating agent can be selected in consideration of conditions such as solubility, concentration, and pH value in the mixed solution of the precursor compound in order to efficiently precipitate the precipitate. Sodium hydrogen carbonate, ethylene glycol and the like can be used.

In forming a mixed solution of the precursor compound, the precursor compound may be mixed with the complex compound in a solution to form a mixed solution. Thereby, a plurality of precursor compounds are reacted with the complex compound to form a composite metal complex compound in which at least one metal element is coordinated, and further, after the composite metal complex compounds are polymerized with each other, the composite metal complex A precipitate obtained by using the compound and the polymer as a metal salt can be obtained.

Here, the complex compound preferably has at least two carboxyl groups as coordination sites and at least one other coordination site. In other words, it is considered that by having three or more coordination sites, at least one metal element can be coordinated, and further, a chain of a polymerization reaction can be formed in the remaining coordination sites. Examples of such a complex compound include ethylenediaminetetraacetic acid (EDTA) and citric acid.

The gel precipitate of the metal salt precipitated from the mixed solution of the precursor compounds is dried and heated (temporarily calcined) to remove contained water and impurities (organic substances, gases, etc.). Is done. Thus, a raw material powder which is a powdery composition containing the metal element constituting the thermistor element 1 in a desired composition can be obtained. continue,
In the second step, the thermistor element 1 is completed using this raw material powder.

In the second step, the obtained raw material powder is granulated,
The lead wires 11 and 12 of Pt or the like are incorporated, molded into a desired shape by a mold or the like, and fired (for example, 1400 ° C. to 1600 ° C.).
Do). Thus, the thermistor element 1 made of a sintered body provided with the lead wires 11 and 12 is obtained. Then, the thermistor element 1 is incorporated in the temperature sensor 100 as shown in FIG.

The evaluation of the resistance characteristics of the thermistor element 1 is performed in a state where the element is incorporated in the temperature sensor 100, and the variation in the resistance value of the thermistor element 1 is evaluated as the temperature accuracy of the temperature sensor 100. The temperature sensor 100 is placed in a high-temperature furnace, and each characteristic (resistance temperature characteristic) of the resistance value and the resistance temperature coefficient β is measured from room temperature (for example, 27 ° C.) to 1000 ° C. Here, β is β (K) = Ln (R / Ro) / (1 / K−1 /
Ko). Note that Ln is a natural logarithm, R and Ro
Are at room temperature (300 K) and 1000 ° C. (1
273K) shows the resistance value of the thermistor element.

The method for evaluating the temperature accuracy is to calculate a standard deviation σ (sigma) of the resistance value at 600 ° C. from the resistance-temperature data of 100 temperature sensors, and to calculate a resistance value six times the standard deviation σ. The variation width (both sides) is used, and the value A obtained by halving the value obtained by converting the resistance variation width into temperature is evaluated as temperature accuracy ± A ° C. Temperature sensor 10 of the present embodiment
As a result of evaluating 0, it was confirmed that the temperature accuracy could be stably achieved at a level of ± 2 to 5 ° C. from room temperature to 600 ° C. (see FIG. 5).

This level of temperature accuracy is in a range applicable to a system or the like requiring high accuracy as described in the section of the subject. Therefore, according to the present embodiment, the variation in the resistance value of the thermistor element can be reduced to the level of the conventional level of temperature accuracy (from room temperature to 600 ° C.).
(± 20 to 30 ° C., see FIG. 9). The temperature sensor 100 using the thermistor element 1 of the present embodiment can achieve better temperature accuracy than the conventional level in a temperature range from room temperature to 1000 ° C.

According to the present embodiment, since a plurality of precursor compounds are dissolved or dispersed in a liquid phase, they can be mixed in a desired composition ratio in a state of atomization to the order of atoms and molecules. Uniform mixing can be achieved. Therefore, the raw material powder can be a composition in which each metal element is uniformly mixed at a desired composition ratio in the order of atoms and molecules, and the thermal reaction can be made uniform even in the subsequent heat treatment. Therefore, consequently,
In the thermistor element manufactured as a sintered body, the composition variation of the constituent crystal particles can be suppressed.

Here, in the sintered body constituting the thermistor element 1, the crystal phase of a crystal phase of a crystal phase which mainly controls the resistance value is confirmed by AEM (analytical electron microscope).
As a result of composition analysis, it was confirmed that there was almost no variation in composition with respect to a desired composition as in the related art, and that the composition could be made uniform in the order of atoms and molecules. Further, as a result of observing the thermistor element 1 with a TEM (transmission electron microscope), each crystal particle is a fine particle having an average particle diameter smaller than 1 μm and several nm (nanometer) to several 100 nm, and each crystal particle is uniformly formed. It was confirmed that the tissue was dispersed and mixed.

(Second Embodiment) In the present embodiment, among the thermistor elements 1, particularly, in the composition (M1M2) O ₃ , M1 is an element belonging to Group 3A except for Group 2A and La of the periodic table. M2 is at least one element selected from the group consisting of Group 3B, Group 4A, Group 5B
At least one element selected from Group A, Group 6A, Group 7A, and Group 8 elements, and (M1M2) O
₃ and Y ₂ O ₃ mixed sintered body (M1M2) O ₃ .Y ₂ O
₃ shows a manufacturing method according to the thermistor element composed of No. ₃ .

Here, the mixed sintered body (M1M2) O ₃ .Y ₂
In O ₃ , the molar fraction of (M1M2) O ₃ is c, Y ₂
Assuming that the molar fraction of O ₃ is d, these c and d are
0.05 ≦ c <1.0, 0 <d ≦ 0.95, c + d = 1
Is preferably satisfied. With this relationship, the resistance temperature coefficient β described in the first embodiment can be adjusted to 2000 to 4000 (° K), and the variation in resistance value due to temperature fluctuation can be reduced. And the thermistor element 1 that can be measured in a wide temperature range from room temperature to 1000 ° C.

Further, in order to obtain a thermistor element 1 that can be measured in a wide temperature range from room temperature to 1000 ° C., M1 is set to Y, Ce, Pr, Nd, Sm, Eu, G
d, Dy, Ho, Er, Yb, Mg, Ca, Sr, B
a and Sc, at least one element selected from the group consisting of
i, V, Cr, Mn, Fe, Co, Ni, Zn, Al,
It is preferable to use at least one element selected from Ga, Zr, Nd, Mo, Hf, Ta, and W.

In the production method of the present embodiment, in the first step (raw material powder production step), a plurality of precursor compounds containing the elements constituting the thermistor element 1 (hereinafter, referred to as constituent elements) are prepared. Is mixed in a liquid phase together with a complex forming agent so as to have a composition, and the plurality of precursor compounds and the complex forming agent are reacted in the mixed solution to form a complex complex compound in which the above constituent elements are coordinated. Then, a polymer containing the above constituent elements is obtained by adding a polymerizing agent to the complex complex compound,
By drying and heat-treating the polymer, a raw material powder containing the above constituent elements is obtained.

As the complexing agent, for example, citric acid,
As the polymerization agent, for example, ethylene glycol can be used. Citric acid, which is a complexing agent, has the advantage that the solubility is high and the complex complex compound can be prepared at a high concentration, so that the water content of the mixed solution can be reduced, and the heat energy required for drying and heat treatment in the subsequent steps can be reduced.

Further, by increasing the concentration of citric acid, the composition of the thermistor becomes more uniform. This is to suppress the elements of the complex complex compound from being redissolved in the mixed solution, and it is possible to reduce the composition variation of the obtained thermistor element. According to the study by the present inventors,
When the number of moles of citric acid is a and the total number of moles of the elements constituting the thermistor element is b, each number of moles a and b is 1 ≦
It has been found that by synthesizing the raw materials under the condition satisfying the relationship of a / b ≦ 30, the thermistor element 1 having good temperature accuracy can be obtained.

When the concentration of citric acid is up to 20-fold equivalent, the obtained polymer is a gel-like viscous solution, but when the concentration of citric acid is increased to 30-fold equivalent, the polymer becomes gel. It does not become a viscous solution but forms colloidal sol particles, which are dispersed in the solution. This is because, when the concentration of citric acid is more than 30 times equivalent, an association / aggregation phenomenon between citric acids occurs,
This is because the polymer obtained thereafter becomes colloidal sol particles, the added citric acid is not effectively used for complex formation, and some of the constituent elements are dissociated in the liquid phase. For this reason, a new problem such as a deviation of the composition from the target composition, or a tendency that the composition variation tends to increase. Therefore, it is preferable that the citric acid concentration satisfy the above relationship.

In the present embodiment, after the first step, a second step (thermistor molding step) is performed using the obtained raw material powder in the same manner as in the first embodiment. The thermistor element 1 made of a mixed sintered body (M1M2) O ₃ .Y ₂ O ₃ provided with lead wires 11 and 12 by performing granulation, drying, molding, firing and the like using the obtained raw material powder.
Get.

Then, this thermistor element 1 is incorporated in the temperature sensor 100 as in the first embodiment, and the resistance characteristics are evaluated (resistance from room temperature to 1000 ° C., resistance temperature coefficient β, temperature accuracy ± A ° C.). Do. As a result of evaluating the temperature sensor 100 of the present embodiment, it can be confirmed that the temperature accuracy can be stably achieved at a level of ± 1.5 to 8 ° C. from room temperature to 600 ° C. (see FIG. 20), and from room temperature to 1000 ° C.
In the temperature range of ° C, it was possible to achieve better temperature accuracy than the conventional level.

By the way, also in this embodiment, since a plurality of precursor compounds are dissolved or dispersed in the liquid phase, the same effects as in the first embodiment can be obtained, and as a result, a mixed sintered body is manufactured. The thermistor element can suppress variation in composition of crystal grains constituting the thermistor element. Further, according to observation by AEM and TEM, the same result as in the first embodiment was obtained.

Next, the first and second embodiments will be described more specifically with reference to Examples 1 to 15 and Comparative Examples 1 to 4 below. However, the present invention is not limited to this. Examples 1 to 9
Explains the first embodiment, and Example 10
15 to 15 are for describing the second embodiment.

[0063]

(Embodiment 1) In this embodiment 1, a mixed sintered body 38 is used.
The raw material powder of the thermistor element 1 made of Y (Cr _0.5 Mn _0.5 ) O ₃ .62Y ₂ O ₃ is synthesized by a liquid phase method using a metal alkoxide as a precursor compound. FIG. 4 shows a manufacturing process of the first embodiment. In FIG. 4, the steps from the blending step to the preliminary firing step correspond to the first step, and the steps from the granulation / drying step to the firing step correspond to the second step.

First, in the first step, the purity was 9%.
9.9% or more of a metal alkoxide as an organometallic compound, triethoxy yttrium: Y (OC
₂ H ₅ ) ₃ and diethoxymanganese: Mn (OC
And ₂ H _5), tris (2,4-Pentajiono) chromium:
Three precursor compounds with Cr [OC (CH ₃ ) CHCOCH ₃ ] ₃ were prepared as starting materials.

Next, the compounding process, finally the composition of the thermistor element _{1, 38Y (Cr 0.5 Mn 0.5)} O 3 · 6
The above three precursor compounds were weighed so as to be 2Y ₂ O ₃ . Further, in order to add Ca as a sintering aid component to the starting material, diethoxycalcium: Ca (OC ₂ H ₅ ) ₂ which is a metal alkoxide is converted to 38Y (C
(r _0.5 Mn _0.5 ) O ₃ .62Y ₂ O _{3 It} was weighed so as to contain 5 wt% with respect to ₃ .

Next, in the dissolving / mixing step, the weighed starting material and Ca (OH ₂ H ₅ ) ₂ are mixed with a mixed solution of ethanol and isopropanol in an amount equivalent to 10 times the starting material, followed by stirring and refluxing. At 40 to 80 ° C. for 10 hours to obtain a mixed metal alkoxide solution as a mixed solution according to the present invention. Subsequently, in the heating / polymerization step,
In order to hydrolyze the composite metal alkoxide solution, pure water as a metal salt precipitant is added, stirred and mixed, and further, in a reflux / precipitation step, reflux is performed at 40 to 80 ° C. for 2 hours. As a result, a gel-like precipitate of a metal salt containing each metal element of the precursor compound was obtained. Then, the precipitate is separated and dried in a separate and drying step, and then temporarily baked in a temporary sintering step to obtain the same 38Y as the composition of the thermistor element 1.
A raw material powder of (Cr _0.5 Mn _0.5 ) O ₃ .62Y ₂ O ₃ composition was obtained.

Next, in the second step, in the granulation / drying step, the obtained raw material powder was granulated by adding a dispersant, a binder and a release agent. Granulation is performed by spray dryer,
A granulated powder of a 38Y (Cr _0.5 Mn _0.5 ) O ₃ .62Y ₂ O ₃ composition was obtained. Subsequently, in the mold forming step, the granulated powder was used to form a thermistor element 1. Molding is carried out by a mold molding method, and Pt100 (φ0.3 mm
× 5 mm) as the lead wires 11 and 12, and the outer diameter φ
The above-mentioned granulated powder is put into a 1.89 mm female mold, and the pressure is about 3
Molding was performed at 500 kgf / cm ² to obtain a molded body of thermistor element 1 to which lead wires 11 and 12 were provided.

Then, in the firing step, the thermistor element 1
Are placed in an Al ₂ O ₃ corrugated setter,
It baked at 400-1600 degreeC for 1-2 hours. Thus,
A mixed sintered body provided with lead wires 11 and 12 (for example, φ
A thermistor element 1 (a 1.6 mm × 1.2 mm cylinder) was obtained. Thereafter, the thermistor element 1 was incorporated into the temperature sensor 100 in a configuration as shown in FIG.

Then, the temperature sensor 100 is placed in a high-temperature furnace, and from room temperature (27 ° C.) to 1000 ° C., the resistance characteristics of the thermistor element, that is, the resistance temperature characteristics (resistance value, resistance temperature coefficient β) and temperature accuracy ± A (° C) were evaluated. FIG. 5 shows the evaluation results together with the thermistor element composition (thermistor raw material composition). FIG. 5 also shows the evaluation results of Examples 2 to 9 described below. In the temperature sensor 100 according to the present example, ± 3 ° C. was obtained as the temperature accuracy, and a good value was obtained.

In addition, the crystal phase (resistance, which mainly controls the resistance value)
Y (Cr_0.5Mn _0.5) O_ThreeCrystal grains
The crystal phase is confirmed by AEM (analytical electron microscope)
And Y (Cr_0.5Mn_0.5) O_ThreeAnalysis of the composition of crystal particles
went. As a result, Y (Cr _0.5Mn_0.5) O_ThreeCrystal grains
The composition of the child is from Y: Cr: Mn = 1: 0.5: 0.5
Y: Cr: Mn = 1: 0.51: 0.49 composition
With little composition variation, atomic and molecular order
It was confirmed that the composition could be made uniform.

The thermistor element 1 is a TEM (transmission type).
As a result of observation with an electron microscope, each crystal particle (in this example,
Y (Cr_0.5Mn_0.5) O_ThreeAnd Y_TwoO_ThreeCrystal particles)
Are fine particles of several nm to several hundred nm, and Y (C
r_0.5Mn_0.5) O_ThreeAnd Y _TwoO_ThreeEach crystal grain is uniform
It was confirmed that the structure was dispersed and mixed. (Embodiment 2) As in Embodiment 1, the present embodiment 2
In the process, the mixed sintered body 38Y (Cr_{0. Five}Mn_0.5) O_Three・
62Y_TwoO_ThreeRaw material powder for thermistor element consisting of
However, the precursor compound is replaced with a complex compound,
Diaminetetraacetic acid (hereinafter referred to as EDTA) was dissolved
This is a liquid phase method of mixing in a solution. This implementation
The manufacturing process of Example 2 is shown in FIG.

Here, in FIG. 6, the steps from the blending step to the preliminary firing step correspond to the first step, and the steps from the granulation / drying step to the firing step correspond to the second step. First, in the first step, yttrium nitrate: Y (NO ₃ ), which is a nitrate as an inorganic metal compound having a purity of 99.9% or more.
₃ · 6H and ₂ O, manganese _{nitrate: Mn (NO 3) 2 ·} 6
And H ₂ O, chromium nitrate: the three precursor compounds of _{Cr (NO 3) 3 · 9H} 2 O were prepared as starting materials.

Next, in the compounding step, finally the thermistor
The composition of the element 1 is 38Y (Cr_0.5Mn_0.5) O_Three・ 62
Y_TwoO_ThreeThese three precursor compounds are weighed so that
Weighed. Further, the starting material for Ca as a sintering aid component is
To be added to the raw material, calcium nitrate, an inorganic metal compound,
Um: Ca (NO_Three)_Three・ 4H_TwoO to 38Y (Cr
_0.5Mn_0.5) O_Three・ 62Y_TwoO_Three5wt%
Was weighed as follows.

Next, in the dissolving / mixing step, the starting material 3
A double equivalent of EDTA was dissolved and mixed in an appropriate amount of pure water. Subsequently, the weighed starting material and Ca (NO ₃ ) ₃ .4H ₂ O
Was dissolved in the solution in which EDTA was dissolved to form a mixed solution according to the present invention. Then, in this mixed solution, each metal ion (Y, Cr, Mn, Ca) and EDTA
Was reacted to prepare a composite metal complex compound in which each of these metal ions was coordinated to the coordination site of EDTA.

Subsequently, in the heating / polymerization step, ethylene glycol, which is a metal salt precipitant, is used to cause a polymerization reaction in the composite metal complex compound to obtain a metal salt precipitate. An excess amount was added, followed by stirring and mixing. Thereafter, the mixed solution was heated at 100 to 200 ° C. to cause a polymerization reaction to proceed, thereby obtaining a polymer in which the composite metal complex compounds were polymerized.

In the precipitation step, when the polymerization reaction has sufficiently proceeded, the heating is stopped, pure water is added in an appropriate amount, and the polymer and the composite metal complex compound (hereinafter, referred to as polymer) are mixed with a metal salt. The resulting gel precipitate was precipitated. Filtered off the precipitate, dried and then calcined, 38 similar to the composition of the thermistor element _{1 (Cr 0.5 Mn 0.5) O} 3 · 6
A raw material powder of the 2Y ₂ O ₃ composition was obtained.

Next, in the second step, the raw material powder obtained is treated in the same manner as in Example 1 above to obtain granulated powder, and this granulated powder is subjected to a mold forming and firing step, and the lead wire 11 is formed. , 12 was obtained as a thermistor element 1 as a mixed sintered body.
Then, in the same manner as in Example 1 described above, the temperature sensor 100 incorporating the thermistor element 1 was evaluated for the resistance-temperature characteristic and the temperature accuracy. FIG. 5 shows the evaluation results. The temperature sensor 100 according to the present example can obtain ± 3 ° C. as the temperature accuracy,
Good value.

AEM composition analysis was performed in the same manner as above,
The composition of crystal grains of Y (Cr _0.5 Mn _0.5 ) O ₃ , which is the resistance dominant phase, is from Y: Cr: Mn = 1: 0.5: 0.5 to Y: Cr: Mn = 1: 0.51: The composition was 0.49, and there was almost no composition variation, and it was confirmed that the composition could be made uniform in the order of atoms and molecules. As a result of the same TEM observation as above, Y (Cr _0.5 Mn _0.5 ) O
₃ and Y ₂ O ₃ each have a particle size of several nm to several hundred nanometers.
m, and it was confirmed that the thermistor element 1 had a structure in which these crystal particles were uniformly dispersed and mixed.

(Embodiment 3) In this embodiment 3, a mixed sintered body 3
It is obtained by synthesizing a raw material powder for a thermistor element made of 8Y (Cr _0.5 Mn _0.5 ) O ₃ .62Y ₂ O ₃ by a liquid phase method using a nitrate salt which is an inorganic metal compound as a precursor compound. FIG. 7 shows a manufacturing process of the third embodiment. In FIG. 7, the steps from the blending step to the preliminary firing step correspond to the first step,
The steps from the granulation / drying step to the firing step correspond to the second step.

First, in the first step, the purity is 99.
99% (4N) or more nitrate, yttrium nitrate
, Manganese nitrate, and three precursor compounds of chromium nitrate
(Each chemical formula is the same as in Example 2 above)
Prepared. And finally, in the compounding process, the thermistor
The composition of the element 1 is 38Y (Cr_0.5Mn_0.5) O_Three・ 62
Y _TwoO_ThreeThese three precursor compounds are weighed so that
And further as a raw material for Ca as a sintering aid component,
(NO_Three)_Three・ 4H_TwoO to 38Y (Cr_0.5M
n_{0. Five}) O_Three・ 62Y_TwoO_Three5 wt%
Was weighed as follows.

Next, in the dissolution / mixing step, the starting material and C
a (NO ₃ ) ₃ .4H ₂ O was dissolved and mixed in an appropriate amount of pure water to form a mixed solution referred to in the present invention. On the other hand, in order to obtain a precipitate of a metal salt from the mixed solution of the inorganic metal compound, sodium bicarbonate: Na ₂ C
O ₃ was dissolved in an appropriate amount of pure water twice as much as the starting material to prepare a sodium hydrogen carbonate solution (precipitant solution preparation step).

Subsequently, in the stirring / mixing step, the inorganic gold
Coprecipitation reaction between mixed solutions of genus compounds and sodium bicarbonate
Sodium bicarbonate to obtain a metal salt precipitate from
Mixed solution of the above inorganic metal compound
After stirring and mixing, a precipitate composed of a composite carbonate was obtained.
Next, the precipitate is separated, dried, and calcined,
38Y (Cr) similar to the composition of the thermistor element 1_0.5Mn
_0.5) O_Three・ 62Y_TwoO _ThreeA raw material powder of the composition was obtained.

Next, in the second step, the raw material powder obtained is treated in the same manner as in Example 1 above to obtain granulated powder, and this granulated powder is subjected to a mold forming and firing step, and the lead wire 11 is formed. , 12 was obtained as a thermistor element 1 as a mixed sintered body.
Then, in the same manner as in Example 1 described above, the temperature sensor 100 incorporating the thermistor element 1 was evaluated for the resistance-temperature characteristic and the temperature accuracy. FIG. 5 shows the evaluation results. The temperature sensor 100 according to the present example can obtain ± 5 ° C. as the temperature accuracy,
Good value.

Further, AEM composition analysis was performed in the same manner as above,
The composition of crystal grains of Y (Cr _0.5 Mn _0.5 ) O ₃ , which is the resistance dominant phase, is as follows: Y: Cr: Mn = 1: 0.48: 0.5
From No. 2, the composition was Y: Cr: Mn = 1: 0.51: 0.49, there was almost no composition variation, and it was confirmed that the composition could be made uniform in the order of atoms and molecules. As a result of the same TEM observation as above, Y (Cr _0.5 M
n _0.5 ) Each crystal particle of O ₃ and Y ₂ O ₃ is a fine particle of several nm to several hundred nm, and the thermistor element 1
It was confirmed that each of these crystal grains had a uniformly dispersed and mixed structure.

(Comparative Example 1) Comparative Example 1 is similar to Examples 1 to
Thermistor element composition 38Y (Cr
_0.5Mn_0.5) O_Three・ 62Y_TwoO_ThreeAnd its manufacturing method
Using a conventional solid phase method. Solid phase method of this example
Then, as a starting material, an oxide Y_TwoO _ThreeAnd Cr_TwoO
_ThreeAnd Mn_TwoO_ThreeAnd CaCO as a sintering aid component_ThreeTo
Mixing and grinding with a conventional ball mill
Was. FIG. 8 shows a manufacturing process of the thermistor element of Comparative Example 1.
You.

First, as a starting material, any purity was 9%.
9.9% or more of Y ₂ O ₃ , Cr ₂ O ₃ and Mn ₂ O ₃
And CaCO ₃ were prepared. In the process of Formulation 1, the composition of the calcined body after the calcining is Y (Cr _0.5 Mn _0.5 ).
O ₃ and such that, Y ₂ O ₃ and Cr ₂ O ₃ and Mn ₂ O ₃
Was weighed. Further, CaCO ₃ is used as a raw material for Ca as a sintering aid component in the form of 38Y (Cr _0.5 Mn _0.5 ) O ₃ .62Y
_It was weighed so as to contain 5 wt% with respect to ₂ O ₃ .

The operation of the ball mill in the mixing step is as follows.
Went like so. Al_TwoO_Three2.5k for boulder φ15mm
g, φ20mm 2.5kg resin pot (volume
Put the weighed starting materials in a volume of 20 liters)
After adding 6000 cc of water, mix at 60 rpm for 6 hours.
The raw material slurry was obtained by pulverization. In the calcination process,
The slurry is dried with a spray dryer and the resulting dried
99.3% Al _TwoO_ThreeInto a crucible made in a high-temperature furnace
Temporary firing at 1100-1300 ° C for 1-2 hours in air
And the composition 38Y (Cr_0.5Mn_0.5) O_Three・ 62Y_TwoO
_ThreeWas obtained.

In the preparation 2 step, a desired amount of the calcined body, which has been formed into a lump solid by calcining, is weighed.
Thereafter, in the pulverizing step (shown as mixing / pulverizing in the figure), a ball mill was used in the same manner as in the mixing step to coarsely pulverize with a raikai machine, pass through a # 30 mesh sieve, and further pulverize. The pulverization conditions by the ball mill were the same as the conditions in the mixing step. In this pulverization step, a dispersant, a binder, and a release agent were added.

The obtained slurry of the thermistor material was powdered, dried and molded in the same manner as in Example 1 to obtain a molded body of a thermistor element. This compact is
_It was placed on a corrugated setter made of ₂ O _{3 and} baked at 1500 to 1600 ° C. for 1 to 2 hours to obtain a thermistor element. The thermistor element of this example has the same shape as the thermistor element 1 shown in FIG. 1 and is incorporated as a thermistor element in a temperature sensor having the same configuration as the temperature sensor 100.

Then, in the same manner as in Example 1 above, the temperature sensor incorporating the thermistor element was evaluated for the resistance-temperature characteristic and the temperature accuracy. FIG. 9 shows the evaluation results. In addition,
The evaluation results of Comparative Examples 2 to 4 described later are also shown in FIG. The temperature sensor according to Comparative Example 1 had the same resistance-temperature characteristics as those of Examples 1 to 3 in which the sintered bodies had the same composition, but the temperature accuracy was inferior to ± 25 ° C. I have.

Further, as in Example 1, the composition of crystal grains of Y (Cr _0.5 Mn _0.5 ) O ₃ , which is the resistance controlling phase, was analyzed by AEM. As a result, Y (Cr
The composition of the _0.5 Mn _0.5 ) O ₃ crystal particles is Y: C
For r: Mn = 1: 0.5: 0.5, Y: Cr: M
n = 1: 0.4: 0.6 to Y: Cr: Mn = 1: 0.
6: 0.4, indicating that the composition had a large variation and was a cause of deterioration in temperature accuracy.

[0092] In the above Examples 1 to 3, the mixed sintered body 38Y
This is an example of the thermistor element 1 made of (Cr _0.5 Mn _0.5 ) O ₃ .62Y ₂ O _3.
9 are thermistor compositions other than Examples 1 to 3,
This is a result of applying the liquid phase method of the present invention. Incidentally, Examples 4 and 5 are 40Y (Cr _0.5 Mn _0.5 ) O ₃ .60A.
l ₂ O ₃ , Examples 6 and 7 were (Y _0.9 Ca _0.1 ) (Cr
_0.75 Fe _0.2 Ti _0.05 ) O ₃ , Examples 8 and 9
It is an example of the thermistor element 1 made of a sintered body of _{0.7 Cr 0.2 Fe 0.1) 2 O} 3 · MgO · CaO.

(Embodiment 4) The present embodiment 4 uses a 40Y (Cr
The _{0.5 Mn 0.5) O 3 · 60Al} 2 O 3 raw material powder of the thermistor element 1 made of a mixed sintered body of, those synthesized by a liquid phase method using a metal alkoxide which is an organic metal compound as a precursor compound. FIG. 10 shows the manufacturing process of the fourth embodiment.
Shown in In FIG. 10, the process from the blending process (formulation 1 and formulation 2) to the calcination process corresponds to the first process, and the process from the granulation / drying process to the firing process corresponds to the second process.

First, triethoxycitrium, which is a metal alkoxide having a purity of 99.9% or more,
Three precursor compounds of diethoxymanganese and tris (2,4-pentadiono) chromium (each having the same chemical formula as in Example 1) were prepared as starting materials. Formulation 1
Finally, the composition of the thermistor element 1 becomes 40Y
The above three precursor compounds were weighed so as to become (Cr _0.5 Mn _0.5 ) O ₃ .60Al ₂ O _3, and diethoxy calcium: Ca was used as a raw material for Ca as a sintering aid component.
(OC ₂ H ₅ ) ₂ was converted to 40Y (Cr _0.5 Mn _0.5 ) O ₃
Were weighed so as to be contained 5 wt% with respect · 60Al ₂ O _3.

Next, in the first dissolution / mixing step, the weighed starting material and Ca (OC ₂ H ₅ ) ₂
The mixed metal alkoxide solution (mixed solution in the present invention) is dissolved and mixed in a double equivalent amount of a mixed solution of ethanol and isopropanol and refluxed at 40 to 80 ° C. for 10 hours in a first stirring / refluxing step. Obtained. Then, in the first heating / polymerization step, pure water (metal salt precipitating agent) was added and stirred and mixed with heating in order to hydrolyze the composite metal alkoxide solution. This mixed solution is called a composite metal polymerization solution.

[0096] On the other hand, in the preparation 2 step, eventually composition of the thermistor element 1 is _{40Y (Cr 0. 5 Mn 0.5)} O 3 ·
60 Al ₂ O ₃ , the precursor compound Al
(OC ₂ H ₅ ) ₃ is weighed, and in the second dissolution / mixing step,
Dissolve and mix in a mixed solution of ethanol and isopropanol 10 times the amount of the starting material, and in the second stirring / refluxing step,
The mixture was refluxed at 40 to 80 ° C. for 10 hours to obtain an Al alkoxide solution. In the second heating / polymerization step, pure water (metal salt precipitant) is added similarly to the composite metal alkoxide solution in order to hydrolyze the Al alkoxide solution.
Stir and mix. This mixed solution is called an Al polymerization solution.

In the reflux / precipitation step, the composite metal polymerization solution and the Al polymerization solution are mixed, and while the mixed solution is stirred, the mixture is further refluxed at 40 to 80 ° C. for 2 hours to form a metal salt. A gel precipitate was obtained. Then, the precipitate is separated by filtration, dried, and calcined to obtain a thermistor element 1
40Y (Cr _0.5 Mn _0.5 ) O ₃ .60 similar in composition to
A raw material powder of the Al ₂ O ₃ composition was obtained.

Next, in the second step, the obtained raw material powder is
In the same manner as in Example 1, the thermistor element 1 was subjected to the steps of granulation / drying, die molding, and firing to obtain a thermistor element 1 as a mixed sintered body provided with the lead wires 11 and 12. Then, the first embodiment
Similarly, the temperature sensor 10 incorporating the thermistor element 1
For 0, the resistance-temperature characteristics and the temperature accuracy were evaluated. FIG. 5 shows the evaluation results. The temperature sensor 100 according to the present embodiment includes:
A temperature accuracy of ± 2 ° C. was obtained, which was a good value.

AEM composition analysis was performed in the same manner as above,
The composition of crystal grains of Y (Cr _0.5 Mn _0.5 ) O ₃ , which is the resistance dominant phase, is from Y: Cr: Mn = 1: 0.5: 0.5 to Y: Cr: Mn = 1: 0.51: The composition was 0.49, and there was almost no composition variation, and it was confirmed that the composition could be made uniform in the order of atoms and molecules. As a result of the same TEM observation as above, Y (Cr _0.5 Mn _0.5 ) O
₃ and Al ₂ O ₃ each have a particle size of several nm to several hundreds.
It was confirmed that the thermistor device 1 was a fine particle having a diameter of nm, and had a structure in which each of the crystal particles was uniformly dispersed and mixed.

(Embodiment 5) Embodiment 5 is different from Embodiment 4 described above.
Similarly, mixed sintered body 40Y in the first step (Cr _{0. 5} Mn
_0.5 ) A raw material powder for a thermistor element composed of O ₃ · 60Al ₂ O ₃ is obtained. As in Example 2, a liquid in which a precursor compound is mixed in a solution in which EDTA as a complex compound is dissolved is mixed. It is a phase method. Example 5
11 is shown in FIG.

Here, in FIG. 11, the steps from the preparation step (preparation 1 and preparation 2) to the preliminary firing step correspond to the first step, and the steps from the granulation / drying step to the firing step correspond to the second step. First, three precursor compounds of yttrium nitrate, manganese nitrate, and chromium nitrate, each of which is a nitrate as an inorganic metal compound having a purity of 99.9% or more (each having the same chemical formula as in Example 2), are used as starting materials. Prepared as.

[0102] In preparation 1 the process, ultimately the composition of the thermistor element _{40Y (Cr 0.5 Mn 0. 5)} O 3 · 60Al
So that ₂ O _3, were weighed the three precursor compounds, further, Ca (NO ₃₎ an inorganic metal compound as a raw material for Ca of the sintering aid component ₃ · 4H ₂ O and 40Y (C
r _0.5 Mn _0.5 ) 5 wt% based on O ₃ · 60 Al ₂ O ₃
Weighed as contained.

Next, in the first dissolving / mixing step, EDTA three times as much as the starting material was dissolved and mixed in an appropriate amount of pure water.
The weighed starting materials and Ca (NO _{3) 3} · 4
H ₂ O was dissolved in the solution in which EDTA was dissolved to form a mixed solution according to the present invention. Subsequently, in the first stirring / refluxing step, each metal ion (Y, Cr, Mn, Ca) is reacted with EDTA in this mixed solution by stirring / refluxing, and each of them is brought into a coordination site of EDTA. A complex metal complex compound having a metal ion coordinated was prepared.

Subsequently, in the first heating / polymerization step, in order to cause a polymerization reaction to occur in the complex complex compound to obtain a precipitate of a metal salt, ethylene glycol which is a metal salt precipitant is subjected to a polymerization reaction. An excess amount was added, followed by stirring and mixing. Thereafter, the mixed solution was heated at 100 to 200 ° C. to allow the polymerization reaction to proceed. This mixed solution is called a composite metal polymerization solution.

[0105] On the other hand, in the preparation 2 step, eventually composition of the thermistor element 1 is _{40Y (Cr 0. 5 Mn 0.5)} O 3 ·
As a _{60Al 2 O 3, Al (NO} 3) 3 · 9H
₂ O is weighed and dissolved in pure water in the second dissolution / mixing step.
The weighed Al (N
O _{3) 3} · 9H ₂ O dissolved and mixed. Subsequently, in a second stirring / refluxing step, stirring / refluxing is performed, and Al (NO ₃ )
A ₃ · 9H ₂ O and EDTA were reacted to prepare the Al complex compound.

Subsequently, in the second heating / polymerization step, this A
In order to cause a polymerization reaction between the complex compound and the complex complex compound to obtain a metal salt precipitate, an excess amount of ethylene glycol as a metal salt precipitant is added to cause a polymerization reaction, followed by stirring. Mixed. After this, the mixed solution was further heated at 100 to 200 ° C. to advance the polymerization reaction. This mixed solution is called an Al polymerization solution.

In the mixing and precipitation step, the composite metal polymerization solution and the Al polymerization solution are mixed, and while the mixed solution is being stirred, heating is stopped when the polymerization reaction has sufficiently proceeded, and pure water is added. (Metal salt precipitation agent)
A gel precipitate containing a polymer or the like as a metal salt was obtained. And
The precipitate was separated by filtration, dried, and calcined to obtain 40Y (Cr _0.5 Mn _0.5 ) O similar to the composition of the thermistor element 1.
To obtain a raw material powder of ₃ · 60Al ₂ O ₃ composition.

Next, in the second step, the obtained raw material powder is
In the same manner as in Example 1, the thermistor element 1 was subjected to the steps of granulation / drying, die molding, and firing to obtain a thermistor element 1 as a mixed sintered body provided with the lead wires 11 and 12. Then, the first embodiment
Similarly, the temperature sensor 10 incorporating the thermistor element 1
For 0, the resistance-temperature characteristics and the temperature accuracy were evaluated. FIG. 5 shows the evaluation results. The temperature sensor 100 according to the present embodiment includes:
A temperature accuracy of ± 2 ° C. was obtained, which was a good value.

AEM composition analysis was performed in the same manner as described above.
The composition of crystal grains of Y (Cr _0.5 Mn _0.5 ) O ₃ , which is the resistance dominant phase, is from Y: Cr: Mn = 1: 0.5: 0.5 to Y: Cr: Mn = 1: 0.51: The composition was 0.49, and there was almost no composition variation, and it was confirmed that the composition could be made uniform in the order of atoms and molecules. As a result of the same TEM observation as above, Y (Cr _0.5 Mn _0.5 ) O
₃ and Al ₂ O ₃ each have a particle size of several nm to several hundreds.
It was confirmed that the thermistor device 1 was a fine particle having a diameter of nm, and had a structure in which each of the crystal particles was uniformly dispersed and mixed.

Comparative Example 2 In Comparative Example 2, a thermistor element composition 40Y (C
r _0.5 Mn _0.5 ) O ₃ .60Al ₂ O _3, and a conventional solid-phase method was used as a production method thereof. In the solid-phase method of this example, oxides of Y ₂ O ₃ and C
Using r ₂ O ₃ , Mn ₂ O ₃ and Al ₂ O ₃ , and CaCO ₃ as a sintering aid component, mixing and grinding were performed by a conventional ball mill. FIG. 12 shows a manufacturing process of the thermistor element of Comparative Example 2.

First, as a starting material, the purity was 9%.
Y of 9.9% or more_TwoO_Three, Cr_TwoO _Three, Mn_TwoO_Three, A
l_TwoO_Three, CaCO_ThreeWas prepared. In the process of Formulation 1,
The composition of the calcined body after the calcining is Y (Cr_0.5Mn
_0.5) O_ThreeSo that Y_TwoO_ThreeAnd Cr_TwoO_ThreeAnd Mn
_TwoO_ThreeWas weighed. Furthermore, the raw material of Ca as a sintering auxiliary component and
And CaCO_ThreeTo 40Y (Cr_0.5Mn_0.5) O_Three・ 6
0Al_TwoO_ThreeWeighed so that 5 wt%
Was. Then, similarly to Comparative Example 1, the mixing step and the preliminary firing
The process is performed and the composition Y (Cr_0.5Mn_0.5) O_ThreeTemporary firing of
I got a body.

Subsequently, in the preparation 2 step, the composition was 40Y
(Cr _0.5 Mn _0.5 ) O ₃ · 60Al ₂ O ₃ , Al ₂ O ₃ is weighed, and then, in a grinding step, the calcined body and the weighed Al ₂ O ₃ are mixed, The pulverization is performed using a ball mill under the same pulverization conditions as in Comparative Example 1. In this pulverizing step, a dispersant, a binder, and a release agent were added as in Comparative Example 1.

From the obtained slurry of the thermistor material, powdering, drying, molding, and firing were performed in the same manner as in Comparative Example 1, and the obtained thermistor element was incorporated into a temperature sensor to obtain a resistance-temperature characteristic. And the temperature accuracy was evaluated. FIG. 9 shows the evaluation results. The temperature sensor according to Comparative Example 2 had the same resistance-temperature characteristics as those of Examples 4 and 5 in which the sintered bodies had the same composition, but the temperature accuracy was ± 23 ° C.
Is inferior.

Further, as in Example 1, the composition of crystal grains of Y (Cr _0.5 Mn _0.5 ) O ₃ , which is the resistance controlling phase, was analyzed by AEM. As a result, Y (Cr
The composition of the _0.5 Mn _0.5 ) O ₃ crystal particles is Y: C
For r: Mn = 1: 0.5: 0.5, Y: Cr: M
n = 1: 0.4: 0.6 to Y: Cr: Mn = 1: 0.
6: 0.4, indicating that the composition had a large variation in composition and was a cause of deterioration in temperature accuracy. (Embodiment 6) In Embodiment 6, (Y _0.9 C
a _0.1) (a _{Cr 0.75 Fe 0.2 Ti 0. 05)} O 3 raw material powder of the thermistor element formed of a sintered body of the composition, in the same manner as in Example 1, a liquid phase method using an organic metal compound as a precursor compound It was obtained by synthesis. FIG. 13 shows a manufacturing process of the sixth embodiment. In FIG. 13, the steps from the blending step to the preliminary firing step correspond to the first step, and the steps from the granulation / drying step to the firing step correspond to the second step.

First, in the first step, the purity was 9%.
Triethoxy yttrium: Y (OC ₂ H ₅ ) ₃ , diethoxy calcium: Ca (OC ₂ H ₅ ) ₂ , and tris (2,4-pentadiono) chromium: Cr, which is a metal alkoxide of 9.9% or more [OC (CH ₃ ) CHCOC
H ₃ ] ₃ and triethoxyiron: Fe (OC ₂ H ₅ )
_3, tetraethoxy titanium: and the five of the precursor compound of Ti (OC ₂ H _{5) 4} was prepared as a starting material.

[0116] In preparation process, eventually the composition of the thermistor element _{(Y 0.9 Ca 0.1) (Cr} 0. 75 Fe 0.2 T
i _0.05 ) The above five precursor compounds were weighed to obtain O ₃ . Next, in the dissolving / mixing step, the weighed starting material is dissolved and mixed in a mixed solution of ethanol and isopropanol in an amount equivalent to 10 times the starting material, and the mixture is stirred and refluxed at 40 to 60 ° C. for 10 hours. Was refluxed to obtain a mixed metal alkoxide solution as a mixed solution in the present invention.

Subsequently, in the heating / polymerization step, in order to hydrolyze the composite metal alkoxide solution, pure water as a metal salt precipitant is added, stirred and mixed, and further subjected to a reflux / precipitation step. The mixture was refluxed at 40 to 60 ° C. for 2 to 4 hours to obtain a gel-like precipitate of the composite metal salt. Then, the precipitate is separated by filtration, dried, and calcined to obtain the same (Y _0.9 Ca _0.1 ) (Cr _0.75 Fe) as the composition of the thermistor element 1.
A raw material powder of _0.2 Ti _0.05 ) O ₃ composition was obtained.

Next, in the second step, the obtained raw material powder is
In the same manner as in Example 1, the thermistor element 1 was subjected to the steps of granulation / drying, mold molding, and firing to obtain a thermistor element 1 as a sintered body provided with the lead wires 11 and 12. Then, in the same manner as in Example 1 described above, the temperature sensor 100 incorporating the thermistor element 1 was evaluated for the resistance-temperature characteristic and the temperature accuracy. FIG. 5 shows the evaluation results. In the temperature sensor 100 according to the present example, ± 5 ° C. was obtained as the temperature accuracy, and a good value was obtained.

In the same manner as described above, the crystal grains (Y _0.9 Ca _0.1 ) (Cr _0.75 Fe _0.2 T
o _0.05 ) The composition of O ₃ was analyzed by AEM. As a result, the crystal grains (Y _0.9 Ca _0.1 ) (Cr _0.75
The composition of Fe _0.2 Ti _0.05 ) O ₃ is Y: Ca: Cr: F
e: Ti = 0.9: 0.1: 0.75: 0.2: 0.0
5 to Y: Ca: Cr: Fe: Ti = 0.9: 0.1:
The composition was 0.74: 0.21: 0.05, and there was almost no composition variation, and it was confirmed that the composition could be made uniform in the order of atoms and molecules.

Further, in the same manner as in the first embodiment, the thermistor
As a result of TEM observation of the data element 1, (Y_0.9Ca_0.1)
(Cr_0.75Fe_0.2Ti_0.05) O_ThreeIs a number n
It was confirmed that the particles had a particle size of m to several 100 nm. (Embodiment 7) As in Embodiment 6, the present embodiment 7
In the process (Y_0.9Ca_0.1) (Cr _0.75Fe_0.2Ti
_0.05) O_ThreeRaw material for thermistor element consisting of sintered body of composition
A powder is obtained, but as in Example 2 above, the precursor compound
In a solution in which EDTA, a complex compound, is dissolved
This is a liquid phase method of mixing. Example 7
The fabrication process is shown in FIG.

Here, in FIG.
The process up to the baking process corresponds to the first process, from the granulation / drying process
The steps up to the firing step correspond to the second step. First, in the first step
Is an inorganic metal compound having a purity of 99.9% or more.
Yttrium nitrate: Y (NO_Three)
_Three・ 6H_TwoO and calcium nitrate: Ca (NO_Three)_Three・
4H_TwoO and chromium nitrate: Cr (NO_Three)_Three・ 9H_TwoO
And iron nitrate: Fe (NO_Three)_Three・ 9H_TwoO and oxynitrate
Titanium oxide: 5TiO_Two・ N_TwoO_Five・ 6H _TwoWith O
Five precursor compounds were provided as starting materials.

In the compounding step, finally, the thermistor element 1
Has the composition (Y_0.9Ca_0.1) (Cr _0.75Fe_0.2Ti
_0.05) O_ThreeThe above five precursor compounds are weighed so that
Weighed. Next, in the dissolution / mixing process, the starting material is quadrupled, etc.
An amount of EDTA was dissolved and mixed in an appropriate amount of pure water. continue,
The weighed starting material is added to the solution in which EDTA is dissolved.
It was dissolved to form a mixed solution according to the present invention. And disrupt
In the stirring / refluxing step, the mixed solution
At the ion of each metal (Y, Ca, Cr, Fe, Ti)
And EDTA to react with
Preparation of complex complex compound in which each metal ion is coordinated
Was.

Subsequently, in the heating / polymerization step, in order to cause a polymerization reaction in the complex complex compound to obtain a precipitate of a metal salt, ethylene glycol, which is a metal salt precipitating agent, is excessively used to cause a polymerization reaction. The amount was added, and the mixture was stirred and mixed. Thereafter, the mixed solution is heated at 80 to 120 ° C,
The polymerization reaction was allowed to proceed. Next, in the precipitation step, when the polymerization reaction sufficiently proceeded, the heating was stopped, and an appropriate amount of pure water (metal salt precipitating agent) was added to obtain a gel precipitate in which the polymer or the like was a metal salt.

[0124] The precipitate is filtered and dried,
After the calcination, the same composition as the thermistor element 1 (Y _0.9
A raw material powder of a Ca _0.1 ) (Cr _0.75 Fe _0.2 Ti _0.05 ) O ₃ composition was obtained. Next, in the second step, the obtained raw material powder is subjected to each of the steps of granulation / drying, die molding, and firing in the same manner as in Example 1, and the sintered body provided with the lead wires 11 and 12 is provided. Was obtained. Then, the first embodiment
Similarly, the temperature sensor 10 incorporating the thermistor element 1
For 0, the resistance-temperature characteristics and the temperature accuracy were evaluated. FIG. 5 shows the evaluation results. The temperature sensor 100 according to the present embodiment includes:
A temperature accuracy of ± 5 ° C. was obtained, which was a good value.

The composition analysis by AEM and the TEM observation
The result of the observation is the same as in Example 6 above,
(Y_0.9Ca_0.1) (Cr_0.75Fe_0.2T
i_0.05) O _ThreeCrystal particles of several nm to several 100 nm
Fine particles with almost no composition variation, atoms,
Confirmation of uniformity of composition in molecular order
did it.

Comparative Example 3 In Comparative Example 3, a thermistor element composition (Y _0.9 Ca) having the same composition as in Examples 6 and 7 was used.
_0.1 ) (Cr _0.75 Fe _0.2 Ti _0.05 ) O _3, and a conventional solid-phase method was used as a production method. In the solid-phase method of this example, Y ₂ O ₃ , Cr ₂ O ₃ , Fe ₂ O ₃ and Ti
Mixing and grinding using O ₂ and CaCo ₃ as starting materials,
Performed with a conventional ball mill. FIG. 15 shows a manufacturing process of the thermistor element of Comparative Example 3.

The starting materials were Y ₂ O ₃ , Cr ₂ O ₃ , Fe ₂ O ₃ , TiO _2, and C having a purity of 99.9% or more.
aCO ₃ was prepared. In the compounding step, the composition of the calcined body after the calcining is (Y _0.9 Ca _0.1 ) (Cr _0.75 Fe
_0.2 Ti _0.05 ) O ₃ was weighed. Then, in the same manner as in Comparative Example 1, the mixing step and the pre-firing step were performed to obtain a pre-fired body.

Subsequently, the obtained calcined body was subjected to the steps of mixing and pulverizing with a ball mill, granulating, molding and firing in the same manner as in Comparative Example 1 to obtain a thermistor element. The obtained thermistor element was incorporated in a temperature sensor, and the resistance-temperature characteristics and the temperature accuracy were evaluated. FIG. 9 shows the evaluation results. The temperature sensor according to Comparative Example 3 had the same resistance-temperature characteristics as those of Examples 6 and 7 in which the sintered bodies had the same composition, but the temperature accuracy was inferior to ± 30 ° C. I have.

[0129] Further, similarly to the above, a resistance value dominated phase _{(Y 0.9 Ca 0.1) (Cr} 0.75 Fe 0. 2 Ti 0.05) O 3
The composition of the crystal grains was analyzed by AEM. As a result, the composition was found to be the target Y: Ca: Cr: Fe: Ti
= 0.9: 0.1: 0.75: 0.2: 0.05, Y: Ca: Cr: Fe: Ti = 0.85: 0.1
From 5: 0.70: 0.15: 0.15, Y: Ca: C
r: Fe: Ti = 0.93: 0.07: 0.78: 0.
It was found that the composition was in the range of 21: 0.01, and the composition variation was large, which was a cause of deterioration in temperature accuracy.

(Embodiment 8) In this embodiment 8, in the first step, (Al _0.7 Cr _0.2 Fe _0.1 ) ₂ O ₃ .MgO.C
It is obtained by synthesizing a raw material powder for a thermistor element comprising a mixed sintered body having an aO composition by a liquid phase method using an organometallic compound as a precursor compound, as in Example 1. FIG. 16 shows a manufacturing process of the eighth embodiment. In FIG.
The steps from the blending step to the preliminary firing step correspond to the first step, and the steps from the granulation / drying step to the firing step correspond to the second step.

First, in the first step, the purity was 9%.
Triethoxyaluminum: Al (OC ₂ H ₅ ) ₃ , which is a metal alkoxide of 9.9% or more, and tris (2,
4 Pentajiono) Chromium: Cr [OC (CH ₃₎ CH
COCH ₃ ] ₃ and triethoxyiron: Fe (OC
Three of the precursor compound of the ₂ H _{5) 3} were prepared as starting materials. In the compounding step, the composition of the thermistor element finally becomes (Al _0.7 Cr _0.2 Fe _0.1 ) ₂ O ₃ .Mg.
The above three precursor compounds were weighed so as to be O.CaO.

Further, the same organometallic compounds as the above-mentioned starting materials are used as the starting materials for the sintering aid components Mg and Ca.
Diethoxymagnesium: Mg (OC ₂ H ₅ ) ₂ and Diethoxycalcium: Ca (OC ₂ H ₅ ) ₂ (both corresponding to precursor compounds) were _converted to (Al _0.7 Cr _0.2 Fe
_0.1 ) The weight was weighed so as to contain 2 wt% with respect to ₂ O ₃ .

Next, in the dissolution / mixing step, the weighed starting materials, Mg (OC ₂ H ₅ ) ₂ and Ca (OC ₂ H ₅ ) ₂
Is dissolved and mixed in a mixed solution of ethanol and isopropanol in an amount equivalent to 10 times the amount of the starting material, and the mixture is stirred and refluxed.
The mixture was refluxed at 40 to 80 ° C. for 10 hours to obtain a mixed metal alkoxide solution as a mixed solution according to the present invention. Subsequently, in the heating / polymerization step, in order to hydrolyze the composite metal alkoxide solution, pure water which is a metal salt precipitant is added, and the mixture is stirred and mixed. The mixture was refluxed at ６０60 ° C. for 2 to 4 hours to obtain a gel-like precipitate of the composite metal salt. The precipitate was separated by filtration, dried, and calcined to obtain the same (A) as the composition of the thermistor element 1.
to obtain a raw material powder of _{l 0.7 Cr O.2 Fe 0.1) 2} O 3 · MgO · CaO composition.

Next, in the second step, the obtained raw material powder is
In the same manner as in Example 1, the thermistor element 1 was subjected to the steps of granulation / drying, mold molding, and firing to obtain a thermistor element 1 as a sintered body provided with the lead wires 11 and 12. Then, in the same manner as in Example 1 described above, the temperature sensor 100 incorporating the thermistor element 1 was evaluated for the resistance-temperature characteristic and the temperature accuracy. FIG. 5 shows the evaluation results. In the temperature sensor 100 according to the present example, ± 5 ° C. was obtained as the temperature accuracy, and a good value was obtained.

In the same manner as described above, the composition of the crystal particles (Al _0.7 Cr _0.2 Fe _0.1 ) ₂ O ₃ constituting the thermistor element was determined by AEM. As a result, the composition of the crystal grains (Al _0.7 Cr _0.2 Fe _0.1 ) ₂ O ₃ is
Al: Cr: Fe = 0.7: 0.2: 0.1 to Al:
It was confirmed that the composition was Cr: Fe = 0.69: 0.21: 0.1, there was almost no composition variation, and the composition was uniformized in atomic or molecular order.

Further, the thermistors were made in the same manner as in the first embodiment.
As a result of TEM observation of the data element 1, (Al_0.7Cr_0.2F
e_0.1)_TwoO_ThreeAnd the crystal particles of MgO and CaO are several n
It was confirmed that the particles had a particle size of m to several 100 nm. (Embodiment 9) As in Embodiment 6 described above, Embodiment 9 employs the first
In the process, (Al_0.7Cr_0.2Fe _0.1)_TwoO_Three・ Mg
Raw material for a thermistor element composed of a sintered body having an O.CaO composition
A powder is obtained, but as in Example 2 above, the precursor compound
In a solution in which EDTA, a complex compound, is dissolved
This is a liquid phase method of mixing. Example 9
The fabrication process is shown in FIG.

Here, in FIG. 17, the steps from the blending step to the preliminary firing step correspond to the first step, and the steps from the granulation / drying step to the firing step correspond to the second step. First, in the first step, aluminum nitrate: Al (N (N), which is a nitrate as an inorganic metal compound having a purity of 99.9% or more.
O ₃₎ and ₃ · 9H ₂ O, chromium nitrate: Cr (NO _{3) 3}
· And 9H ₂ O, iron nitrate: the three precursor compound with _{Fe (NO 3) 3 · 9H} 2 O were prepared as starting materials.

In the compounding step, finally, the thermistor element 1
The composition of _{(Al 0.7 Cr 0.2 Fe 0. 1} ) 2 O 3 · MgO
-The above five precursor compounds were weighed to obtain CaO. Further, magnesium nitrate: Mg (NO ₃ ) ₂ .6H ₂ O and calcium nitrate: Ca (NO ₃ ) _2. 4H ₂ O, (Al _0.4 Cr
_0.2 Fe _0.1 ) ₂ O _{3 with} respect to 2 wt% and 2 wt%, respectively.
It was weighed so as to contain wt%.

Next, in the dissolution / mixing step, the starting material 3
A double equivalent of EDTA was dissolved and mixed in an appropriate amount of pure water. Subsequently, the starting material, Mg (NO ₃ ) ₂ .6H ₂ O and Ca
(NO ₃ ) ₂ .4H ₂ O was dissolved in a solution in which EDTA was dissolved to form a mixed solution referred to in the present invention. In the stirring / refluxing step, each metal (Al, Cr, Fe, Mg,
By reacting the Ca) ion with EDTA, a complex complex compound in which each of these metal ions was coordinated to the coordination site of EDTA was prepared.

Subsequently, in the heating / polymerization step, in order to cause a polymerization reaction to occur in the complex complex compound to obtain a precipitate of the metal salt, an excess amount of ethylene glycol as a metal salt precipitant is used to cause the polymerization reaction. The amount was added, and the mixture was stirred and mixed. Thereafter, the mixed solution is heated at 80 to 120 ° C,
The polymerization reaction was allowed to proceed. Next, in the precipitation step, when the polymerization reaction was sufficiently advanced, the heating was stopped, and an appropriate amount of pure water (metal salt precipitant) was added to obtain a precipitate in which the polymer or the like was a metal salt.

Then, the precipitate was separated by filtration and dried,
By calcination, the same as the composition of the thermistor element 1 (Al
A raw material powder of _0.7 Cr _0.2 Fe _0.1 ) ₂ O ₃ .MgO.CaO composition was obtained. Next, in the second step, the obtained raw material powder is subjected to each of the steps of granulation / drying, die molding, and firing in the same manner as in Example 1, and the sintered body provided with the lead wires 11 and 12 is provided. Was obtained. Then, the first embodiment
Similarly, the temperature sensor 10 incorporating the thermistor element 1
For 0, the resistance-temperature characteristics and the temperature accuracy were evaluated. FIG. 5 shows the evaluation results. The temperature sensor 100 according to the present embodiment includes:
A temperature accuracy of ± 5 ° C. was obtained, which was a good value.

The results of the composition analysis and the TEM observation by AEM are the same as those in Example 8, and the crystal grains of (Al _0.7 Cr _0.2 Fe _0.1 ) ₂ O ₃ , which is the resistance dominant phase, have a composition variation. It was confirmed that the composition was almost uniform in the order of atoms and molecules. Also, (Al _0.7 Cr _0.2 Fe _0.1 ) ₂ O ₃ and MgO,
It was confirmed that the CaO crystal particles were fine particles of several nm to several 100 nm.

(Comparative Example 4) Comparative Example 4 is the same as Example 8
Thermistor element composition (Al_{0. 7}Cr
_0.2Fe_0.1)_TwoO_Three・ MgO ・ CaO and manufacture
This is a method using a conventional solid phase method. In this example
In the phase method, Al_TwoO_ThreeAnd Cr_TwoO_ThreeAnd Fe _TwoO_ThreeAnd Mg
O and CaCO_ThreeMixing and milling
I went with the next ball mill. Of the thermistor element of Comparative Example 4
FIG. 18 shows the manufacturing process.

First, as a starting material, the purity was 9%.
9.9% or more Al_TwoO_ThreeAnd Cr_TwoO _ThreeAnd Fe_TwoO_ThreeWhen
MgO and CaCO_ThreeWas prepared. In the compounding process, calcination
The composition of the calcined body after that is (Al_0.7Cr_0.2Fe
_0.1)_TwoO_Three-It was weighed so that it might become MgO * CaO.
A mixing step and a calcination step were performed in the same manner as in Comparative Example 1 above.
A calcined body was obtained.

Subsequently, the raw slurry of the obtained calcined body was mixed and mixed by a ball mill in the same manner as in Comparative Example 1.
The thermistor element was subjected to each of the steps of pulverization, granulation, molding, and firing to obtain a thermistor element. The obtained thermistor element was incorporated in a temperature sensor, and the resistance-temperature characteristics and the temperature accuracy were evaluated. FIG. 9 shows the evaluation results. The temperature sensor according to Comparative Example 4 includes:
As compared with the above Examples 8 and 9, which are sintered bodies having the same composition, the resistance-temperature characteristics were almost the same, but the temperature accuracy was ±
Inferior at 30 ° C.

In the same manner as described above, the composition of crystal grains of (Al _0.7 Cr _0.2 Fe _0.1 ) ₂ O ₃ , which is the resistance dominant phase, was analyzed by AEM, and as a result, the target Al: Cr: Fe = 0.7: 0.2: 0.1
On the other hand, Al: Cr: Fe = 0.78: 0.17:
From 0.05, Al: Cr: Fe = 0.65: 0.23:
The range of the composition was 0.12, and it was found that the composition had a large variation and the temperature accuracy was deteriorated.

Example 10 In Example 10, a raw material powder for the thermistor element 1 comprising a mixed sintered body 38Y (Cr _0.5 Mn _0.5 ) O ₃ .62Y ₂ O ₃ was obtained. Is synthesized by a liquid phase method using citric acid as a complexing agent and ethylene glycol as a polymerizing agent. FIG. 19 shows a manufacturing process of the tenth embodiment.
In FIG. 19, the process from the blending process to the heat treatment process is the first process.
Process from granulation / drying to baking
It corresponds to a process.

First, in the first step, the purity was 9%.
9.9% or more of nitrate as an inorganic metal compound;
Yttrium nitrate: Y (NO _{3) 3} · and 6H ₂ O, manganese nitrate: Mn (NO ₃₎ and ₂ · 6H ₂ O, chromium _{nitrate: Cr (NO 3) 3 ·} 9H three precursor compound with ₂ O Was prepared as a starting material. Next, in the compounding step, finally, the composition of the thermistor element 1 is 38Y (Cr _0.5 Mn).
_0.5 ) A total of 1000 g of these three precursor compounds was weighed so as to obtain O ₃ · 62Y ₂ O ₃ . Further, in order to add the Ca raw material of the sintering aid component to the starting raw material,
Calcium nitrate, an inorganic metal compound: Ca (NO ₃ )
The _{3 · 4H 2 O, 38Y (} Cr 0.5 Mn 0.5) O 3 · 6
It was weighed so as to contain 5 wt% with respect to 2Y ₂ O ₃ .

Next, in the dissolving / mixing step, first, the number of moles of citric acid is set to a, and the compositions Y, Cr, M of the thermistor element 1 are set.
600 g of citric acid is added to 2 liters of pure water so that the citric acid concentration becomes a / b = 1 (hereinafter, defined as 1 equivalent), where b is a value obtained by converting the total amount of each of the constituent elements of n into moles. To give a citric acid solution. Subsequently, in the stirring / refluxing step, the starting material and calcium nitrate are added to the citric acid solution, and each element ion (Y, Cr, Mn, Ca) is added.
And citric acid were reacted to form a complex complex compound in which each of these element ions was coordinated to the coordination site of citric acid.

Subsequently, in the heating / polymerization step, in order to obtain a polymer of this complex complex compound, 100 ml of ethylene glycol was added as a polymerization agent, and the mixture was stirred and mixed. It heated at ℃, and the polymerization reaction was advanced. Then, when the polymerization reaction sufficiently proceeded, the heating was stopped, and a polymer as a gel-like viscous solution was obtained.

Next, in the drying step, the polymer was dried at 99.degree.
It is placed in a 7% alumina crucible, dried, and heat-treated at 600 to 1000 ° C. in a heat treatment step to obtain 38Y (Cr _0.5 Mn _0.5 ) O ₃ similar to the composition of the thermistor element 1.
A raw powder which was a 62Y ₂ O ₃ composition was obtained. Next, the second
Then, the same process as in Example 1 above was performed, and the obtained raw material powder was used as granulated powder. The granulated powder was subjected to a mold forming and firing step, and mixed with lead wires 11 and 12 provided. A thermistor element 1 as a sintered body was obtained.

As in the first embodiment, the temperature sensor 100 incorporating the thermistor element 1 has a resistance-temperature characteristic (resistance value, resistance temperature coefficient β) and a temperature accuracy (± A
° C). FIG. 20 shows the evaluation results together with the citric acid concentration. In addition, FIG.
The results of the evaluation of 15 are also shown. Temperature sensor 1 according to this example
In the case of 00, a temperature accuracy of ± 5 ° C. was obtained, which was a good value.

Further, the thermistor element 1 of this embodiment is
FIG. 21 shows the results of quantitative analysis of the constituent elements of Y, Cr, and Mn by (electron probe mass analysis). In addition,
FIG. 21 also shows the analysis results of the following Examples 11 to 15 and the analysis result of Comparative Example 1 by the conventional solid-phase method. As can be seen from FIG. 21, in this example, it was confirmed that the composition variation (standard deviation σ: unit at%) of each constituent element was reduced to almost 比 べ compared with the conventional solid phase method. . In addition, in the conventional solid phase method (Comparative Example 1), it was confirmed that the composition variation was larger than that in the liquid phase method, and the temperature accuracy was deteriorated due to the increase in the composition variation.

(Embodiment 11) This embodiment 11 is different from the embodiment shown in FIG.
9, a raw material powder for the thermistor element 1 made of the mixed sintered body 38Y (Cr _0.5 Mn _0.5 ) O ₃ .62Y ₂ O ₃ is obtained in the same manufacturing process as in the above-mentioned Example 10.
The difference is that the concentration of citric acid, which is a complexing agent, is twice equivalent, and a precursor powder is obtained by reacting a precursor compound of each constituent element with citric acid.

The obtained raw material powder is subjected to the second step, and the mixed sintered body 38Y (Cr
_A thermistor element 1 of _0.5 Mn _0.5 ) O ₃ · 62Y ₂ O ₃ was obtained, and the temperature sensor 100 incorporating the same was evaluated for the resistance-temperature characteristic and the temperature accuracy (± A ° C.) in the same manner as in the first embodiment. (See FIG. 20). In the temperature sensor 100 according to the present example in which the citric acid concentration was twice equivalent, a temperature accuracy of ± 4 ° C. was obtained, which was a good value. Also in this example, as in Example 10, as a result of the EPMA analysis (see FIG. 21), the variation in the composition of each constituent element was reduced to about 1/3 as compared with the conventional solid phase method. Was confirmed.

(Embodiment 12) This embodiment 12 is different from the embodiment shown in FIG.
9, a raw material powder for the thermistor element 1 made of the mixed sintered body 38Y (Cr _0.5 Mn _0.5 ) O ₃ .62Y ₂ O ₃ is obtained in the same manufacturing process as in the above-mentioned Example 10.
The difference is that the concentration of the citric acid as the complexing agent was set to be four times the same, and a precursor powder was obtained by reacting a precursor compound of each constituent element with citric acid.

The obtained raw material powder is subjected to the second step, and the mixed sintered body 38Y (Cr
_A thermistor element 1 of _0.5 Mn _0.5 ) O ₃ · 62Y ₂ O ₃ was obtained, and the temperature sensor 100 incorporating the same was evaluated for the resistance-temperature characteristic and the temperature accuracy (± A ° C.) in the same manner as in the first embodiment. (See FIG. 20). In the temperature sensor 100 according to the present example in which the concentration of citric acid was set to 4 times the equivalent, ± 3 ° C. was obtained as the temperature accuracy, and a good value was obtained. Also in this example, as in Example 10, the result of EPMA analysis (see FIG. 21) showed that the compositional variation of each constituent element was approximately 1/3 to 1 / 4 was confirmed.

(Thirteenth Embodiment) A thirteenth embodiment will be described with reference to FIG.
9, a raw material powder for the thermistor element 1 made of the mixed sintered body 38Y (Cr _0.5 Mn _0.5 ) O ₃ .62Y ₂ O ₃ is obtained in the same manufacturing process as in the above-mentioned Example 10.
The difference is that the concentration of citric acid, which is a complexing agent, is 10 times the same, and a raw material powder is obtained by reacting a precursor compound of each constituent element with citric acid.

The obtained raw material powder is subjected to the second step, and the mixed sintered body 38Y (Cr
_A thermistor element 1 of _0.5 Mn _0.5 ) O ₃ · 62Y ₂ O ₃ was obtained, and the temperature sensor 100 incorporating the same was evaluated for the resistance-temperature characteristic and the temperature accuracy (± A ° C.) in the same manner as in the first embodiment. (See FIG. 20). In the temperature sensor 100 according to the present example in which the citric acid concentration was set to 10 times the equivalent, ± 1.5 ° C. was obtained as the temperature accuracy, which was a good value. Also, in this embodiment, similarly to the tenth embodiment, the EPM
As a result of the A analysis (see FIG. 21), it was confirmed that the composition variation of each constituent element was reduced to about 1/4 as compared with the conventional solid phase method.

(Embodiment 14) The embodiment 14 is different from the embodiment shown in FIG.
9, a raw material powder for the thermistor element 1 made of the mixed sintered body 38Y (Cr _0.5 Mn _0.5 ) O ₃ .62Y ₂ O ₃ is obtained in the same manufacturing process as in the above-mentioned Example 10.
The difference is that the concentration of citric acid as a complexing agent is 20 times the same, and a precursor powder is obtained by reacting a precursor compound of each constituent element with citric acid.

The obtained raw material powder is subjected to the second step, and the mixed sintered body 38Y (Cr
_A thermistor element 1 of _0.5 Mn _0.5 ) O ₃ · 62Y ₂ O ₃ was obtained, and the temperature sensor 100 incorporating the same was evaluated for the resistance-temperature characteristic and the temperature accuracy (± A ° C.) in the same manner as in the first embodiment. (See FIG. 20). In the temperature sensor 100 according to the present example in which the citric acid concentration was set to 20 times the equivalent, ± 1.5 ° C. was obtained as the temperature accuracy, which was a good value. Also, in this embodiment, similarly to the tenth embodiment, the EPM
As a result of the A analysis (see FIG. 21), it was confirmed that the composition variation of each constituent element was reduced to about 1/4 as compared with the conventional solid phase method.

(Embodiment 15) The embodiment 15 is different from the embodiment shown in FIG.
9, a raw material powder for the thermistor element 1 made of the mixed sintered body 38Y (Cr _0.5 Mn _0.5 ) O ₃ .62Y ₂ O ₃ is obtained in the same manufacturing process as in the above-mentioned Example 10.
The difference is that the concentration of citric acid as a complexing agent is 30 times the same, and a precursor powder of each constituent element is reacted with citric acid to obtain a raw material powder.

Incidentally, as in the above Examples 10 to 14,
When the concentration of enic acid is up to 20-fold equivalent, the polymer obtained is
This is a viscous solution in the form of a citric acid.
Is equal to 30 times, the polymer becomes a gel-like viscous solution.
Sol particles are partially solid colloidal sol particles
It became a dispersed form. Therefore, in the drying step,
So that there is no deviation from the target thermistor composition
Then, transfer the total amount of the fixed sol and solution to the alumina / crucible
, Dry, heat treatment process, thermistor element
38Y (Cr_0.5Mn _0.5) O_Three・
62Y_TwoO_ThreeA raw material powder as a composition was obtained.

The obtained raw material powder is subjected to the second step, and the mixed sintered body 38Y (Cr
_A thermistor element 1 of _0.5 Mn _0.5 ) O ₃ · 62Y ₂ O ₃ was obtained, and the temperature sensor 100 incorporating the same was evaluated for the resistance-temperature characteristic and the temperature accuracy (± A ° C.) in the same manner as in the first embodiment. (See FIG. 20). In the temperature sensor 100 according to the present example in which the citric acid concentration was 30 times the equivalent, ± 8 ° C. was obtained as the temperature accuracy, and a good value was obtained. Also,
Also in this example, as in Example 10, the result of EPMA analysis (see FIG. 21) shows that the composition variation of each constituent element has been reduced to almost ほ ぼ compared to the conventional solid-phase method. That was confirmed.

(Other Examples) Hereinafter, other embodiments and examples of the present invention will be described. In Example 1 and the like, a metal alkoxide that is an organometallic compound was used as a precursor compound, and a solution containing an alcohol was used as a solvent. However, an organometallic compound stably existing in an aromatic solvent such as benzene or xylene was used. For example, SYM-Y01 (trade name, manufactured by Symmetrics Corporation) or the like can be used as a Y (yttrium) compound. Further, an organic metal compound stably present in an organic ester solvent, for example, Y-03 (trade name, manufactured by Kojundo Chemical Co., Ltd.) or the like can be used as the Y compound.

Furthermore, in Example 1 and the like, a single metal alkoxide or the like which is an organometallic compound was used as the precursor compound. For example, a plurality of metal elements, Y, Cr and M
n-containing metal alkoxide (complex alkoxide), Y
Complex alkoxide containing Ca, Cr, Fe and Ti,
Metal alkoxide containing Al, Cr and Fe, Mg and Ca
Thermistor raw material powder can be prepared in the same manner as in Example 1 and the like using a composite alkoxide containing

In Examples 2, 5, 7, and 9, EDTA was used as the complex compound. However, any complex compound to which a metal ion is coordinated may be used. Examples thereof include citric acid, acetate, and oxalate. A thermistor raw material powder can be prepared in the same manner as in Example 2 and the like by using, for example, stearate. Further, in the above Examples 1 to 15, for example, φ1.6
Although a small bulk thermistor element 1 having a column shape of mm × 1.2 mm is obtained, the present invention does not depend on the shape. For example, it does not depend on the shape of the thermistor element obtained in the above embodiment. For example, a binder, a resin material, and the like are mixed and added to the raw material powder of the thermistor element obtained in each of the above embodiments, and the viscosity and hardness suitable for sheet molding are adjusted. A sheet is obtained, and five such thermistor sheets are laminated to a thickness of 1 mm, and the same effect as in the above embodiment can be obtained in a sheet laminated thermistor element provided with a lead wire.

Further, a binder, a resin material and the like are mixed and added to the raw material powder of the thermistor element obtained in each of the above embodiments to adjust the viscosity and hardness suitable for extrusion molding, and a lead wire is provided by extrusion molding. By obtaining a molded body of a thermistor element in which a hole is formed, loading a lead wire and firing the same, the same performance as in the above embodiment can be obtained even in a thermistor element in which a lead wire is formed.

In Examples 1 to 9, a single compound such as an organometallic compound, a complex compound, or an inorganic metal compound is used as a precursor compound. However, when a raw material having a uniform composition is obtained, For example, when a starting material is a precursor compound obtained by combining an inorganic metal compound and an organometallic compound, or when a starting material is obtained from a precursor compound obtained by combining an organometallic compound and a complex compound, the combination of the precursor compounds is as follows. It doesn't matter.

In the above Examples 1 to 9, the precursor compound was mixed and dissolved in various solvents such as alcohol and pure water. A raw material powder for a thermistor element can also be obtained by adding a medium, a dispersant, or an acid or alkali solution to adjust the pH (hydrogen ion concentration). Further, for example, in the above Examples 1 to 3, Y (Cr
The _0.5 Mn _{0. 5)} O ₃ and Y ₂ O ₃ is a high-resistance phase, homogeneous mixture from precursor compounds together, dissolved, and to obtain a raw material powder having an aim composition of the thermistor element, the resistance value dominated phase Is prepared by the liquid phase method to obtain a raw material powder, and when the raw material powder is mixed with another composition by a solid phase method using a ball mill or the like to obtain a thermistor element, the thermistor element obtained by the conventional solid phase method Temperature accuracy is improved as compared with.

In the above embodiment, the raw material powder is prepared by a chemical liquid phase method in which a metal salt precipitant is added to the mixed solution of the precursor compound to precipitate a precipitate. Even when a thermistor raw material powder is prepared from a solution by a physical liquid phase method such as a spray pyrolysis method, a pyrolysis method, a lyophilization method, and a solution combustion method without adding a metal salt precipitating agent, a conventional solid phase can be used. Compared with the thermistor element obtained by the method, the composition variation can be suppressed and the temperature accuracy can be improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a thermistor element according to an embodiment of the present invention.

FIG. 2 is a sectional configuration diagram of a temperature sensor using the thermistor element of FIG.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a manufacturing process diagram of the thermistor element of Example 1 of the present invention.

FIG. 5 is a table showing resistance characteristics of the thermistor elements of Examples 1 to 9 of the present invention.

FIG. 6 is a manufacturing process diagram of the thermistor element of Example 2 of the present invention.

FIG. 7 is a manufacturing process diagram of the thermistor element according to Example 3 of the present invention.

FIG. 8 is a manufacturing process diagram of the thermistor element of Comparative Example 1.

FIG. 9 is a table showing resistance characteristics of the thermistor elements of Comparative Examples 1 to 4.

FIG. 10 is a manufacturing process diagram of the thermistor element of Example 4 of the present invention.

FIG. 11 is a manufacturing process diagram of the thermistor element of Example 5 of the present invention.

FIG. 12 is a manufacturing process diagram of the thermistor element of Comparative Example 2.

FIG. 13 is a manufacturing process diagram of the thermistor element according to Example 6 of the present invention.

FIG. 14 is a manufacturing process diagram of the thermistor element according to Example 7 of the present invention.

FIG. 15 is a manufacturing process diagram of the thermistor element of Comparative Example 3.

FIG. 16 is a manufacturing process diagram of the thermistor element of Example 8 of the present invention.

FIG. 17 is a manufacturing process diagram of the thermistor element according to Example 9 of the present invention.

FIG. 18 is a manufacturing process diagram of the thermistor element of Comparative Example 4.

FIG. 19 is a manufacturing process diagram of the thermistor elements according to Examples 10 to 15 of the present invention.

FIG. 20 is a table showing resistance characteristics of the thermistor elements according to Examples 10 to 15 of the present invention.

FIG. 21 is a table showing composition variations of Examples 10 to 15 and Comparative Example 1 of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Thermistor element, 2 ... Metal cap, 3 ... Metal pipe, 11, 12 ... Lead wire, 31, 32 ... Metal pipe lead wire, 33 ... Magnesia powder.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masanori Yamada 14 Iwatani, Shimowasumi-cho, Nishio-shi, Aichi Japan Inside the Japan Automotive Parts Research Institute (72) Inventor Kaoru Kuzuoka 1-1-1, Showa-cho, Kariya-shi, Aichi Stock Inside DENSO Corporation (72) Inventor Etsuro Yasuda 14th Iwatani, Shimowasumi-cho, Nishio-shi, Aichi Japan Inside Japan Automotive Parts Research Institute

Claims (13)

[Claims] 1. A manufacturing method for manufacturing a thermistor element comprising a sintered body, comprising: mixing a plurality of precursor compounds containing a metal element in a liquid phase to form a mixed solution; Adding a metal salt precipitating agent to the mixture to precipitate a gel-like precipitate of a metal salt containing a plurality of the metal elements; and drying and heating the precipitate to contain the plurality of the metal elements. A method for producing a thermistor element, comprising: a step of forming a raw material powder that is a powdery composition; and a step of firing the raw material powder to form the sintered body. 2. In the step of forming the mixed solution,
The plurality of precursor compounds may have at least 2
Having two carboxyl groups and being mixed with a complex compound having at least one other coordination site in a liquid phase to form the mixed solution; and in the mixed solution, the plurality of precursor compounds and the plurality of The method for producing a thermistor element according to claim 1, wherein the complex compound is reacted with the complex compound to form a composite metal complex compound in which at least one of the metal elements is coordinated. 3. The method according to claim 2, wherein ethylenediaminetetraacetic acid (EDTA) or citric acid is used as the complex compound. 4. The method according to claim 1, wherein the precursor compound is one or more organometallic compounds selected from metal alkoxides, metal acetylacetonates and metal carboxylate. A method for manufacturing the thermistor element according to the above. 5. The method according to claim 1, wherein the precursor compound is at least one inorganic metal compound selected from a nitrate compound, an oxynitrate compound, a chloride and an oxychloride. 5. A method for manufacturing a thermistor element according to any one of the above. 6. A method for producing a thermistor element comprising a sintered body, comprising: mixing a plurality of precursor compounds containing a metal element in a liquid phase to form a mixed solution; A step of forming a raw material powder that is a powdery composition containing a plurality of the metal elements, and a step of firing the raw material powder to form the sintered body. Method. 7. The sintered body manufactured by the manufacturing method according to claim 1, wherein a particle size of the sintered body is 1 μm.
A temperature sensor having a smaller thermistor element. 8. The composition (M1M2) O ₃ wherein M1
Is at least one element selected from Group 2A elements of the periodic table and elements of Group 3A excluding La;
Are groups 3B, 4A, 5A, 6A of the periodic table of elements
Group, at least one or more elements selected from the Group 7A and Group 8 elements of the (M1M2) mixed sintered body of the O ₃ and Y ₂ O ₃ (M1
M2) A method for producing a thermistor element composed of O ₃ · Y ₂ O ₃ , wherein a plurality of precursor compounds containing the elements constituting the thermistor element and a complexing agent are mixed in a liquid phase. Forming a mixed solution, reacting the plurality of precursor compounds with the complex forming agent in the mixed solution to form a complex complex compound, and adding a polymerizing agent to the complex complex compound. A step of forming a united body; a step of forming a raw material powder containing an element constituting the thermistor element by drying and heat-treating the polymer; ) O ₃・
Forming a Y ₂ O ₃ . 9. When citric acid is used as the complexing agent and ethylene glycol is used as the polymerizing agent, and when the number of moles of the citric acid is a and the total number of moles of the elements constituting the thermistor element is b, 1 9. The method for manufacturing a thermistor element according to claim 8, wherein a relationship of ≦ a / b ≦ 30 is satisfied. 10. When the mole fraction of (M1M2) O ₃ is c and the mole fraction of Y ₂ O ₃ is d, these c
And d are 0.05 ≦ c <1.0, 0 <d ≦ 0.9
10. The method for manufacturing a thermistor element according to claim 8, wherein a relation of c + d = 1 is satisfied. 11. The method according to claim 11, wherein M1 is Y, Ce, Pr, Nd,
Sm, Eu, Gd, Dy, Ho, Er, Yb, Mg, C
a, Sr, Ba, Sc, at least one element selected from the group consisting of Ti, V, Cr, Mn, Fe, Co,
Ni, Zn, Al, Ga, Zr, Nd, Mo, Hf, T
The method for manufacturing a thermistor element according to any one of claims 8 to 10, wherein the element is at least one element selected from a and W. 12. M1 is Y, M2 is Cr and Mn.
And the mixed sintered body is Y (CrMn) O ₃ .Y ₂ O
Method for producing a thermistor element according to claim 11, characterized in that it is _3. 13. A temperature sensor comprising a thermistor element manufactured by the manufacturing method according to claim 8. Description: