JP3590646B2 - Conductive material and method of manufacturing the same - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a conductive material used for an antistatic agent or a static control agent such as a resin, a surface conductivity-imparting agent, a conductive paint, a sputtering target or a transparent electrode of a display device, and a method for producing the same.
[0002]
[Prior art]
As a transparent, white or light-colored conductive material, a material obtained by adding antimony to tin oxide (ATO), a material obtained by adding tin to indium oxide (ITO), a material obtained by adding aluminum to zinc oxide, and the like are known. . These are added to a synthetic resin or the like in a powder state for antistatic or electrostatic control, and are used to adjust the electric resistance value of the resin. It is also added to conductive paints and the like used for imparting surface conductivity (for example, as a primer for electrostatic coating).
[0003]
Further, a sintered body is prepared by molding and sintering the powder into a predetermined shape to obtain a target material. Then, a transparent electrode for a display device is formed on a glass or resin substrate by a sputtering method, a vapor deposition method, an ion plating method, or the like using a target made of the sintered body.
[0004]
[Problems to be solved by the invention]
However, ITO and ATO have the drawback that when they are powdered, their moisture resistance is relatively low, and their electrical resistance increases due to moisture. In addition, since ITO and ATO powders are blackened in a reduced state, they have a disadvantage that when added to a resin, it becomes difficult to freely color a resin product. Further, a target made of an ITO or ATO sintered body is also easily blackened by reduction, so that a change with time in its characteristics is a problem.
[0005]
An object of the present invention is to provide a conductive material that has better moisture resistance than ITO and ATO, is hardly blackened, and has the same conductivity as ITO and ATO, and a method for manufacturing the same.
[0006]
[Means for Solving the Problems]
The conductive material of the present invention that achieves the above object contains In and Zn as main components and has the general formula In₂O₃(ZnO)_mA conductive material comprising a powder containing a hexagonal layered compound represented by (m = 2 to 20), or a sintered body obtained by molding the powder into a predetermined shape and sintering the same (hereinafter, this conductive material). The conductive material is referred to as a conductive material I). Further, the hexagonal layered compound contains at least one element having a valence of positive trivalence or more in an amount of 20 atomic% or less based on the total amount of all cation elements forming the hexagonal layered compound. A conductive material characterized in that it also achieves the above object (hereinafter, this conductive material is referred to as a conductive material II).
[0007]
On the other hand, the method for producing a conductive material of the present invention that achieves the above object uses an indium compound and a zinc compound, and forms a precipitate formed by a precipitate forming agent from at least one solution containing at least one of these compounds. Solid-liquid separation, if necessary, firing and reduction treatment to obtain a conductive powder, and when obtaining a sintered body, after forming the powder into a predetermined shape, sintering to obtain a conductive sintered body This is a method for producing a conductive material (hereinafter, this method is referred to as method I). Further, using at least one compound of an indium compound, a zinc compound, and an element having a valence of three or more positive, a precipitate formed by a precipitate-forming agent from one or more solutions containing at least one of these compounds, Solid-liquid separation, if necessary, firing and reduction treatment to obtain a conductive powder, and when obtaining a sintered body, forming the powder into a predetermined shape and sintering to obtain a conductive sintered body A method for producing a conductive material characterized by the above object also achieves the above object (hereinafter, this method is referred to as method II).
[0008]
Hereinafter, the present invention will be described in detail.
[0009]
First, the conductive material I of the present invention contains In and Zn as main components as described above, and has the general formula In₂O₃(ZnO)_mA powder containing a hexagonal layered compound represented by (m = 2 to 20) or a sintered body obtained by molding the powder into a predetermined shape and sintering the same. .
[0010]
Here, “a powder or a sintered body containing a hexagonal layered compound” refers to a sintered body or a hexagonal layered compound made of a substance exhibiting an X-ray diffraction pattern attributed to the hexagonal layered compound in X-ray diffraction measurement. Means a substance exhibiting an X-ray diffraction pattern attributed to another structure, a substance exhibiting an X-ray diffraction pattern attributed to another structure, a powder containing an amorphous substance, or a sintered body.
[0011]
More specifically, this powder or sintered body contains at least 20% by weight, more preferably at least 30% by weight, particularly preferably at least 50% by weight of a hexagonal layered compound. Preferred examples thereof include the following. Can be
[0012]
(A). In₂O₃(ZnO)_m(M = 2 to 20) a hexagonal layered compound,
(B). In₂O₃(ZnO)_m(M = 2 to 20) hexagonal layered compound and In₂O₃A mixture with
(C). In₂O₃(ZnO)_mA mixture of a hexagonal layered compound (m = 2 to 20) and ZnO,
In (b) and (c), In₂O₃And ZnO may be crystalline or amorphous.
[0013]
In the conductive material I of the present invention, the atomic ratio of In to Zn (In / (In + Zn)) is preferably 0.1 to 0.9. The reason is that if it is less than 0.1, the conductivity of the conductive material will be low, and if it exceeds 0.9, the moisture resistance and heat resistance of the conductive material will be reduced. The atomic ratio (In / (In + Zn)) is more preferably from 0.5 to 0.9, and particularly preferably from 0.6 to 0.8.
[0014]
The above atomic ratio of In and Zn is obtained by adjusting the mixing ratio of the indium compound and the zinc compound at the time of forming the precipitate, and a hexagonal layered compound composed of indium oxide and zinc oxide corresponding to the stoichiometric ratio is obtained. It is presumed that the generated indium oxide and zinc oxide are present as crystalline or amorphous substances.
[0015]
As described above, the conductive material I of the present invention is made of the indium / zinc oxide powder or sintered body. This conductive material I has better moisture resistance than ITO and ATO, and is blackened by reduction. It is difficult and has the same conductivity as ITO and ATO, and is used in the above-mentioned various applications (antistatic agent, surface conductivity imparting agent, conductive paint, sputtering target, transparent electrode of display device, etc.).
[0016]
The conductive material I can be manufactured by various methods such as a gas phase method (CVD method) and a solid phase method (physical mixing method). Method).
[0017]
Next, the conductive material II of the present invention will be described.
[0018]
This conductive material II contains In and Zn as main components and has the general formula In₂O₃(ZnO)_m(M = 2 to 20) to the hexagonal layered compound represented by formula (1), at least one element having a valence of positive trivalent or higher is added to the hexagonal layered compound by 20 atoms based on the total amount of all cation elements forming the hexagonal layered compound. % Or a sintered body obtained by molding and sintering the powder into a predetermined shape. Here, as the element having a valence of positive trivalent or higher, there are Al, Ga (positive trivalent), Si, Ge, Sn (positive tetravalent), and Sb (positive pentavalent) elements. Sn having a large effect is desirable.
[0019]
The element having a valence of 3 or more is a hexagonal layered compound In₂O₃, ZnO, or both.
[0020]
Further, in the present invention, a part of the element having a valence of three or more is an oxide that does not form a hexagonal layered compound or another oxide (for example, In₂O₃, ZnO).
[0021]
“Powder or sintered body containing a hexagonal layered compound” is understood in the same manner as the conductive material I.
[0022]
In the conductive material II of the present invention, when an element having a valence of three or more, for example, Sn, Al, Ga, Sb, Si or Ge is added in excess of 20 atomic%, a hexagonal layered compound is formed. And the conductivity may be reduced.
[0023]
Since the conductive material II of the present invention has better moisture resistance than ITO and ATO, is hardly blackened, and has the same conductivity as ITO and ATO, the above-mentioned various uses (antistatic agent, surface conductivity imparting agent) , Conductive paints, sputtering targets, transparent electrodes of display devices, etc.).
[0024]
The conductive material II can also be produced by various methods such as a gas phase method (CVD method) and a solid phase method (physical mixing method), but according to a method II of the present invention described later, a solution method (coprecipitation method). )).
[0025]
Next, the method I and the method II of the present invention will be described.
[0026]
First, the method I of the present invention uses an indium compound and a zinc compound as described above, and separates a precipitate formed by a precipitate-forming agent from one or more solutions containing at least one of them by solid-liquid separation. In the case where a conductive powder is obtained by firing and reducing treatment to obtain a sintered body, the powder is formed into a predetermined shape and then sintered to obtain a conductive sintered body.
[0027]
The indium compound and the zinc compound used as the raw materials in the method I may be oxides or oxides after firing (oxide precursors). Indium oxide precursors and zinc oxide precursors include indium, zinc sulfide, sulfate, nitrate, halide (chloride, bromide, etc.), carbonate, organic acid salt (acetate, propionate, Naphthenate, etc.), alkoxides (methoxide, ethoxide, etc.), organometallic complexes (acetylacetonate, etc.) and the like.
[0028]
In particular, nitrates, organic acid salts, alkoxides, and organometallic complexes are preferably used among them in order to completely decompose at low temperature and prevent impurities from remaining.
[0029]
In the method I, a precipitate is first formed, and the formation of the precipitate can be specifically performed by the following method.
[0030]
First, a solution in which an indium compound and a zinc compound are dissolved, or a solution in which at least an indium compound is dissolved and a solution in which at least a zinc compound is dissolved, and a solution in which a precipitate forming agent is dissolved are prepared, and separately prepared containers (if necessary, A solvent may be added), and if necessary, the above-mentioned solutions may be added simultaneously or sequentially with stirring to form a precipitate.
[0031]
Further, a solution in which a precipitate forming agent is dissolved may be added to a solution in which an indium compound and a zinc compound are dissolved, or vice versa.
[0032]
For example, a case in which a solution in which an indium compound and a zinc compound are dissolved and a solution in which a precipitate forming agent is dissolved are separately prepared, and the two solutions are simultaneously added to a vessel containing a solvent while stirring to form a precipitate. This will be described in detail below.
[0033]
First, a solution (hereinafter, referred to as solution A) in which the indium compound and the zinc compound are dissolved in an appropriate solvent is prepared. The solvent may be appropriately selected depending on the solubility of the indium compound or the zinc compound to be used. For example, water, alcohol, aprotic polar solvents (DMSO, NMP, sulfolane, THF, etc.) can be used, and the solvent is formed. Alcohols having 1 to 5 carbon atoms (such as methanol, ethanol, isopropanol, methoxyethanol, and ethylene glycol) are particularly preferred because of low solubility of the precipitate. The concentration of each metal in the solution A is preferably 0.01 to 10 mol / liter. The reason is that if it is less than 0.01 mol / l, productivity is poor, and if it exceeds 10 mol / l, a non-uniform precipitate is formed. Further, in order to promote the dissolution of the raw materials, acids (nitric acid, hydrochloric acid, etc.), acetylacetones, polyhydric alcohols (ethylene glycol, etc.), ethanolamines (monoethanolamine, diethanolamines) in the solution are appropriately used in various solvents. You may add about 0.01 to 10 times the amount of metal.
[0034]
In the method I, a solution in which the precipitate forming agent is dissolved (hereinafter, referred to as a solution B) is also prepared together with the solution A. Examples of the precipitate-forming agent dissolved in the solution B include alkalis (such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, ammonium hydroxide, ammonium carbonate, and ammonium bicarbonate), and organic acids. (Formic acid, oxalic acid, citric acid, etc.) are used, but it is preferable to use an organic acid (especially oxalic acid) in order to avoid contamination with impurities. The precipitate is converted to a hydroxide, an inorganic acid salt, or an organic acid salt by the precipitate forming agent.
[0035]
As the solvent for dissolving the precipitate-forming agent and the solvent to be put in the container for forming the precipitate, the above-mentioned solvents used for dissolving the raw materials can be used.
[0036]
As the solvent used for the various solutions, it is better to use the same solvent in operation, but different solvents may be used.
[0037]
In the method I, a precipitate is formed by any of the above-mentioned means, and the temperature at the time of forming the precipitate may be any temperature as long as it is higher than the melting point of the solvent and lower than the boiling point. After formation, aging may be performed for 1 to 50 hours.
[0038]
According to method I, the precipitate obtained as described above is then subjected to solid-liquid separation and drying. Solid-liquid separation of the precipitate is performed by a conventional method such as centrifugation, filtration and the like. After the solid-liquid separation, in order to remove anions, alkali metal ions, and the like from the precipitate, it is desirable to sufficiently wash the separated product with the solvent used for the solutions A and B or another solvent. Drying after filtration is preferably performed at 40 to 200 ° C. for 0.1 to 100 hours. At a low temperature, drying takes too much time, and at a high temperature, aggregation of particles tends to occur.
[0039]
According to the method I, after the solid-liquid separation and drying, baking, pulverization and reduction treatment are performed.
[0040]
The calcination is preferably performed at 300 to 1200 ° C. for 0.1 to 100 hours, depending on the indium compound and zinc compound used. At a low temperature and a short time, the decomposition of the oxide precursor of indium or zinc into an oxide becomes insufficient, and at a high temperature and a long time, aggregation of particles and scattering of components tend to occur.
[0041]
Pulverization after firing is preferably performed by a ball mill, a roll mill, a jet mill, a pearl mill or the like until the particle diameter becomes 0.01 to 10 μm. The grinding time is usually 1 minute to 500 hours.
[0042]
The reduction treatment is preferably performed in an atmosphere of a reducing gas (hydrogen, CO, etc.), vacuum, inert gas (nitrogen, argon) or the like at a temperature of 100 to 800 ° C. for 1 minute to 100 hours. If the temperature is low and the time is short, the reduction is insufficient, and if the temperature is high and the time is long, agglomeration of particles and scattering of components are likely to occur. This reduction treatment is preferably performed after the firing step or the pulverizing step.
[0043]
According to the method I, by performing the above-mentioned steps, In and Zn are used as main components, and the general formula In₂O₃(ZnO)_mA conductive powder containing a hexagonal layered compound represented by (m = 2 to 20) is obtained. This conductive powder is an embodiment of the conductive material I of the present invention, and has better moisture resistance than ITO and ATO, is hardly blackened, and has the same conductivity as ITO and ATO. The volume solid resistance (sometimes expressed as “powder resistance”) of this powder is, for example, 40 Ω · cm or less.
[0044]
In the method I, when obtaining a conductive sintered body, the conductive powder is molded and then sintered.
[0045]
Molding may be performed by adding a molding aid such as polyvinyl alcohol, methylcellulose, wax, or polybutyl alcohol to the conductive powder, if necessary, and performing pressure molding, casting, injection molding, or the like. preferable.
[0046]
Generally, the molding aid is degreased and removed at 100 to 800 ° C. under reduced pressure or normal pressure.
[0047]
Sintering after molding is preferably performed by heating at 800 to 1700 ° C. for 0.1 to 100 hours.
[0048]
If the temperature is low and the time is short, the sintering density is insufficient, and if the temperature is high and the time is long, abnormal grain growth and scattering of components tend to occur. In particular, it is preferable to set the temperature at 800 to 1400 ° C. for 1 to 20 hours. At the time of sintering, pressure sintering or gas pressure sintering may be performed.
[0049]
The thus obtained, having In and Zn as main components, having the general formula In₂O₃(ZnO)_mThe conductive sintered body containing the hexagonal layered compound represented by (m = 2 to 20) is one embodiment of the conductive material I of the present invention, and has better moisture resistance than ITO and ATO, and Are hardly blackened and have the same conductivity as ITO and ATO.
[0050]
Next, the method II of the present invention will be described.
[0051]
As described above, this method II uses at least one element selected from the elements having a valence of positive trivalent or higher (for example, a tin compound, an aluminum compound, a gallium compound, an antimony compound, a silicon compound and a germanium compound) in the indium compound and the zinc compound. The method is different from the above-mentioned method I only in that a seeded product is used as a raw material.
[0052]
Elements having a valence of three or more (eg, tin compounds, aluminum compounds, gallium compounds, antimony compounds, silicon compounds, and germanium compounds) used in Method II are oxides or oxides after firing (oxide precursors). ) Is fine. These oxide precursors include sulfides, sulfates, nitrates, halides (chlorides, bromides, etc.), carbonates, organic acids of the respective elements (for example, Sn, Al, Ga, Ab, Si and Ge). Salts (eg, acetate, propionate, naphthenate), alkoxides (eg, methoxide, ethoxide), and organometallic complexes (eg, acetylacetonate) are included.
[0053]
Among these, nitrates, organic acid salts, alkoxides, and organometallic complexes are preferably used in order to completely decompose at low temperature and prevent impurities from remaining.
[0054]
According to Method II, the hexagonal layered compound contains at least one element having a valence of positive trivalent or higher in an amount of 20 atomic% or less based on the total amount of all cation elements forming the hexagonal layered compound. The intended conductive material II (powder or sintered body) can be obtained. The obtained conductive material II has better moisture resistance than ITO and ATO, is hardly blackened by reduction, and has the same conductivity as ITO and ATO.
[0055]
The powder or the sintered body obtained by the methods I and II may be further subjected to a reduction treatment.
[0056]
The conductive powder of the present invention can be used as an antistatic resin composition by mixing with various resins.
[0057]
Resins that can be used include thermoplastics such as polyethylene, polypropylene, polystyrene, vinyl chloride, vinyl acetate, polyvinyl alcohol, vinylidene chloride, ABS resin, polyester, methyl methacrylate, polyurethane, polyamide, polyacetal, polycarbonate, silicon resin, and fluororesin. Resins; thermosetting resins such as phenolic resins, urea resins, melamine resins, xylene resins, furan resins, alkyd resins, epoxy resins, and polyimide resins.
[0058]
It is preferable to add 1 to 600 parts by weight of the conductive powder to 100 parts by weight of the resin. If the amount is small, the conductivity becomes insufficient, and if it is large, the physical properties of the resin may be impaired. In order to improve the dispersibility of the conductive powder, the surface of the conductive powder may be treated with a surface treatment agent (such as a silane coupling agent, a titanium coupling agent, or an aluminate coupling agent).
[0059]
In addition, various other additives (plasticizers, stabilizers, lubricants, inorganic fillers (calcium carbonate, mica, glass, talc, etc.), inorganic fibers (glass fibers, carbon fibers, etc.), whiskers (potassium titanate, zinc oxide whiskers, etc.) ), A surfactant or the like may be added.
[0060]
Examples of the method of mixing the conductive powder and the resin include a method of kneading the mixture in a heated state or at normal temperature using a two-roll, three-roll or injection molding machine, or a method of mixing the powder with a solution in which the resin is dissolved. Conventional means can be used.
[0061]
【Example】
Hereinafter, examples of the present inventionWith reference examplesFirst, the embodiment will be described.And reference examplesThe method for measuring the physical properties of the substance obtained in the above will be described.
[0062]
[Measuring method]
(1) Measurement of particle size and composition
The particle diameter was measured with a scanning electron microscope (SEM), and the composition was measured with an XMA (X-ray microanalyzer).
[0063]
(2) Determination of hexagonal layered compound
Using a powder X-ray diffractometer, the content of the hexagonal layered compound was quantified by the method described in “Characterization Technology of Ceramics”, published by The Ceramic Society of Japan, 1987, pp. 44-45.
[0064]
(3) Measurement of volume solid resistance
Volume solid resistance (sometimes expressed as "powder resistance") is measured by placing 1 g of a sample in a resin cylinder having an inner diameter of 10 mm, and applying 100 kg / cm²Was pressed, and the resistance was measured with a tester.
[0065]
Volume solid resistance (Ωcm)
= [(Total resistance (Ω) x inner area of cylinder (cm²)] / Sample thickness (cm)
[0066]
referenceExample 1
(1) In₂O₃(ZnO)₃Production of powder containing hexagonal layered compound
First, 70.97 g of indium nitrate and 89.25 g of zinc nitrate were dissolved in 1 liter of ion-exchanged water to prepare an aqueous solution in which an indium salt and a zinc salt were dissolved. Also, 78 g of aqueous ammonia (concentration: 28%) was dissolved in 750 cc of ion-exchanged water to prepare an alkaline aqueous solution.
[0067]
Next, the aqueous solution obtained above and the alkaline aqueous solution were simultaneously added dropwise to a 5 liter container containing 100 cc of ion-exchanged water at room temperature with vigorous stirring to react the two solutions. At this time, the dropping rate was adjusted so that the pH of the reaction system was maintained at 9.0. Then, after the completion of the dropping, the mixture was further stirred for 1 hour. By reacting the aqueous solution and the alkaline aqueous solution in this manner, a precipitate was formed, and a slurry was obtained. The metal (In and Zn) concentration in this reaction system was 0.3 mol / L.
[0068]
Next, the obtained slurry was sufficiently washed with water, and the precipitate was collected by filtration. Then, the precipitate collected by filtration was dried at 120 ° C. overnight, and then calcined at 900 ° C. for 5 hours.
[0069]
Thereafter, the obtained fired product was placed in a polyimide pot having a capacity of 80 cc together with alumina balls having a diameter of 2 mm, and ethanol was added thereto, followed by grinding with a planetary ball mill for 2 hours.
[0070]
An X-ray diffraction measurement was performed on the powder thus obtained.₂O₃(ZnO)₃The formation of a hexagonal layered compound was confirmed, and the composition was substantially uniform. Further, as a result of SEM observation, it was confirmed that the obtained powder had an average particle diameter of 0.12 μm and a substantially uniform particle diameter.
[0071]
The volume solid resistance of the obtained powder was 950 Ω · cm. This volume solid resistance is as low as 1000 Ω · cm even after 1000 hours of the moisture resistance test under the conditions of 40 ° C. and 90% RH (relative humidity), and it is confirmed that the obtained powder has excellent moisture resistance. Was.
[0072]
(2) In₂O₃(ZnO)₃Production of sintered body containing hexagonal layered compound
First, the powder obtained in the above (1) was charged into a mold of 10 mmφ, and 100 kg / cm²Preforming was performed at a pressure of Next, 4 t / cm by a cold isostatic press molding machine.², And sintered at 1300 ° C for 5 hours to obtain a sintered body.
[0073]
The sintered body thus obtained is 80 wt% of In.₂O₃(ZnO)₃It was confirmed that the conductive material I contained the hexagonal layered compound of Example 1. The composition and the particle size were substantially uniform. The density of the sintered body was 95%.
[0074]
(3) Production of transparent conductive film
Using the sintered body obtained in the above (2) as a sputtering target, a transparent conductive film was produced in the following manner.
[0075]
First, a substrate (glass plate having a thickness of 125 μm) was mounted on a magnetron high-speed sputtering apparatus, and the inside of a vacuum chamber was 1 × 10 5^-6The pressure was reduced to below torr. Thereafter, a mixed gas of argon gas and oxygen gas was pumped at a vacuum pressure of 2 × 10^-3The pressure was increased to Torr, and sputtering was performed under the conditions of a target applied voltage of 430 V and a substrate temperature of 280 ° C., thereby forming a 200 nm-thick transparent conductive film.
[0076]
The surface resistance of the transparent conductive film thus obtained was 150Ω / □, and the visible light transmittance was 82%. The surface resistance was as low as 159 Ω / □ even after 1000 hours of the moisture resistance test under the conditions of 40 ° C. and 90% RH, and it was confirmed that the obtained transparent conductive film was excellent in moisture resistance.
[0077]
referenceExample 2
(1) In₂O₃ (ZnO)₅Production of powder containing hexagonal layered compound
First, 50.69 g of indium nitrate and 106.24 g of zinc nitrate are dissolved in 1 liter of ion-exchanged water to prepare an aqueous solution in which an indium salt and a zinc salt are dissolved.referenceAn alkaline aqueous solution prepared in the same manner as in Example 1 (1)referenceThe reaction was carried out in the same manner as in Example 1 (1) to obtain a slurry. The metal (In and Zn) concentration in this reaction system was 0.3 mol / liter.
[0078]
Next, the obtained slurry was sufficiently washed with water, and the precipitate was collected by filtration. Then, the precipitate collected by filtration was dried at 120 ° C. overnight, and then calcined at 900 ° C. for 5 hours.
[0079]
After this, the obtained fired product isreferencePulverization was performed in the same manner as in Example 1 (1) to obtain a powder.
[0080]
An X-ray diffraction measurement was performed on the powder thus obtained.₂O₃(ZnO)₅The formation of a hexagonal layered compound was confirmed, and the composition was substantially uniform. Further, as a result of SEM observation, it was confirmed that the obtained powder had an average particle diameter of 0.20 μm and a substantially uniform particle diameter.
[0081]
The volume solid resistance of the obtained powder was 700 Ω · cm. The volume solid resistance was as low as 730 Ωcm even after 1000 hours of the moisture resistance test at 40 ° C. and 90% RH, and it was confirmed that the obtained powder had excellent moisture resistance.
[0082]
(2) In₂O₃(ZnO)₅Production of sintered body containing hexagonal layered compound
The powder obtained in the above (1)referenceAfter preforming and consolidating in the same manner as in Example 1 (2), sintering was performed at 1350 ° C. for 5 hours to obtain a sintered body.
[0083]
The sintered body thus obtained is 80 wt% of In.₂O₃(ZnO)₅Was confirmed to be a conductive material I containing a hexagonal layered compound, and its composition and particle size were substantially uniform. The density of the sintered body was 96%.
[0084]
(3) Production of transparent conductive film
Except that the sintered body obtained in the above (2) was used as a sputtering targetreferenceA transparent conductive film having a thickness of 200 nm was formed in the same manner as in Example 1 (3).
[0085]
The surface resistance of the transparent conductive film thus obtained was 110Ω / □, and the visible light transmittance was 84.1%. In addition, the surface resistance was as low as 118 Ω / □ even after 1000 hours of the moisture resistance test under the conditions of 40 ° C. and 90% RH, and it was confirmed that the obtained transparent conductive film had excellent moisture resistance.
[0086]
referenceExample 3
(1) Tin-containing In₂O₃(ZnO)₅Production of powder containing hexagonal layered compound
referenceAfter preparing an aqueous solution in which a metal salt of indium and zinc was dissolved in the same manner as in Example 2 (1), 7.2 g (5 atomic%) of stannic chloride was further added thereto. Next, this aqueous solution,referenceAn alkaline aqueous solution prepared in the same manner as in Example 1 (1)referenceThe reaction was carried out in the same manner as in Example 1 (1) to obtain a slurry.
[0087]
Next, the obtained slurry was sufficiently washed with water, and the precipitate was collected by filtration. Then, the precipitate obtained by filtration was dried at 120 ° C., and calcined at 900 ° C. for 5 hours. The mixture was placed in a polyimide pot having a volume of 80 cc together with the balls, and ethanol was added thereto, followed by grinding with a planetary ball mill for 2 hours.
[0088]
After this, the obtained fired product isreferencePulverization was performed in the same manner as in Example 1 (1) to obtain a powder.
[0089]
As a result of X-ray diffraction measurement of the powder thus obtained, 60 wt% of In₂O₃(ZnO)₅It was confirmed that a hexagonal layered compound was produced. The volume solid resistance of the powder was 330 Ω · cm. Then, this volume solid resistance was as low as 350 Ω · cm even after 1000 hours of the moisture resistance test under the conditions of 40 ° C. and 90% RH, and it was confirmed that the obtained powder was excellent in moisture resistance.
[0090]
(2) Tin-containing In₂O₃(ZnO)₅Production of sintered body containing hexagonal layered compound
The powder obtained in the above (1)referenceAfter preforming and consolidating in the same manner as in Example 1 (2), sintering was performed at 1350 ° C. for 5 hours to obtain a sintered body.
[0091]
The sintered body thus obtained is 80 wt% of In.₂O₃(ZnO)₅It was confirmed that the conductive material I was composed of a hexagonal layered compound, and the composition and particle size were substantially uniform. The density of the sintered body was 95%.
[0092]
(3) Production of transparent conductive film
Except that the sintered body obtained in the above (2) was used as a sputtering target,referenceA transparent conductive film having a thickness of 200 nm was formed in the same manner as in Example 1 (3).
[0093]
The surface resistance of the transparent conductive film thus obtained was 70 Ω / □, and the visible light transmittance was 85.0%. The surface resistance was as low as 75 Ω / □ even after 1000 hours of the moisture resistance test under the conditions of 40 ° C. and 90% RH, and it was confirmed that the obtained transparent conductive film had excellent moisture resistance.
[0094]
Example1
(1) In₂O₃(ZnO)₅Production of powder containing hexagonal layered compound
A solution A was obtained by dissolving 350.5 g of indium nitrate hexahydrate and 637.5 g of zinc nitrate hexahydrate in 5.00 liter of ethanol.
[0095]
On the other hand, 475.4 g of oxalic acid dihydrate was dissolved in 5.00 liter of ethanol to obtain a solution B.
[0096]
At room temperature, 1.00 liter of ethanol was put in a container and stirred, and solutions A and B controlled at the same flow rate were simultaneously dropped therein. After completion of the dropwise addition, the temperature was raised to 40 ° C., and the precipitate was aged for 4 hours. Thereafter, the precipitate was filtered, washed with ethanol and dried at 110 ° C. for 12 hours. Furthermore, it baked at 700 degreeC for 4 hours. After pulverization with a ball mill (20 hours), the powder was subjected to a reduction treatment at 300 ° C. for 4 hours in a vacuum to obtain a pale yellow powder.
[0097]
X-ray diffraction measurement of the powder thus obtained showed that 70 wt% of In was obtained.₂O₃(ZnO)₅Generation was confirmed. Furthermore, when the volume solid resistance of the powder was measured, it was 25 Ω · cm. The volume solid resistance was still 32 Ω · cm even after 1000 hours of the moisture resistance test under the conditions of 40 ° C. and 90% RH, which proved to be excellent in moisture resistance. In addition, SEM and XMA analysis revealed that this powder had an average particle size of 0.22 μm and a uniform composition.
[0098]
(2) In₂O₃(ZnO)₅Production of sintered body containing hexagonal layered compound
2 wt% of polyvinyl alcohol is added to the powder obtained in (1), and 100 kg / cm in a mold having a diameter of 150 mm.²And press molded. Furthermore, 4t / cm²At a cold isostatic press.
[0099]
The molded body was degreased at 500 ° C. for 10 minutes and then sintered at 1200 ° C. for 4 hours. In the sintered body thus obtained, 90 wt% of In was determined by X-ray diffraction measurement.₂O₃(ZnO)₅Generation was confirmed. The density of the sintered body was 92%, and the volume resistance was 5 × 10^-3Ω · cm.
[0100]
Example2
(1) In₂O₃(ZnO)₃Production of powder containing hexagonal layered compound
Solution A was obtained by dissolving 293.2 g of indium chloride tetrahydrate and 351.2 g of zinc acetate dihydrate in 5.00 liter of ethanol.
[0101]
On the other hand, 415.9 g of oxalic acid dihydrate was dissolved in 5.00 liter of ethanol to obtain a solution B.
[0102]
Example using solution A and solution B1A pale yellow powder was obtained in the same manner as in (1). X-ray diffraction measurement of the powder showed that 60 wt% of In₂O₃(ZnO)₃Generation was confirmed. Furthermore, when the volume solid resistance of the powder was measured, it was 18 Ω · cm. The volume solid resistance was 25 Ω · cm even after 1000 hours of the moisture resistance test under the conditions of 40 ° C. and 90% RH, which proved to be excellent in moisture resistance. In addition, SEM and XMA analyzes revealed that this powder had an average particle size of 0.15 μm and a uniform composition.
[0103]
(2) In₂O₃(ZnO)₃Hexagonal layered compound and In₂O₃ Of sintered body containing
Example using powder obtained in (1) above1A sintered body was obtained in the same manner as in (2). In the sintered body thus obtained, 80 wt% of In was measured by X-ray diffraction measurement.₂O₃(ZnO)₃Generation was confirmed. The density of this sintered body was 93%, and the volume resistance was 2 × 10^-3Ω · cm.
[0104]
Example3
(1) Tin-containing In₂O₃(ZnO)₅Production of powder containing hexagonal layered compound
350.5 g of indium nitrate hexahydrate, 637.5 g of zinc nitrate hexahydrate and nasem tin ((Sn (Cn₄H₉)₂(C₅H₇O₂)₂) 108 g was dissolved in 5.00 liter of methoxyethanol to obtain a solution A.
[0105]
On the other hand, 472.5 g of oxalic acid dihydrate was dissolved in 5.00 liter of ethanol to obtain a solution B.
[0106]
Using these solutions A and B,1A powder was prepared in the same manner as in (1). This powder was also pale yellow.
[0107]
X-ray diffraction measurement of the powder showed that 60 wt% of In₂O₃(ZnO)₅Generation was confirmed. Furthermore, when the volume solid resistance of the powder was measured, it was 15 Ω · cm. The volume solid resistance was 19 Ω · cm even after 1000 hours of the moisture resistance test under the conditions of 40 ° C. and 90% RH, which proved to be excellent in moisture resistance. In addition, SEM and XMA analyzes revealed that this powder had an average particle size of 0.21 μm and a uniform composition.
[0108]
(2) Tin-containing In₂O₃(ZnO)₅Production of sintered body containing hexagonal layered compound
Example using powder obtained in (1) above1A sintered body was obtained in the same manner as in (2). In the sintered body thus obtained, 80 wt% of In was measured by X-ray diffraction measurement.₂O₃(ZnO)₅Generation was confirmed. The density of this sintered body is 91%, and the volume resistance is 1 × 10^-3Ω · cm.
[0109]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the conductive material which is more excellent in moisture resistance than ITO and ATO, hardly blackens, and has the same conductivity as ITO and ATO, and its manufacturing method were provided.

Claims (8)

A powder containing a hexagonal layered compound containing In and Zn as main components and represented by a general formula In ₂ O ₃ (ZnO) _m (m = 2 to 20), or a powder formed into a predetermined shape and sintered. Ri Do a sintered body, a conductive material, wherein the volume solids resistivity of the powder is less than 40 [Omega · cm. The hexagonal layered compound contains at least one element having a valence of three or more positive valences in an amount of 20 atomic% or less based on the total amount of all cation elements forming the hexagonal layered compound. Item 6. The conductive material according to Item 1. A conductive material obtained by subjecting the powder or sintered body according to claim 1 to a reduction treatment. Using an indium compound and a zinc compound, a precipitate formed by a precipitate-forming agent is solid-liquid separated from one or more solutions containing at least one of them, and if necessary, calcined and reduced to form a conductive powder. The method for producing a conductive material according to claim 1, wherein the conductive material is obtained. The method for producing a conductive material according to claim 1, wherein the powder obtained in claim 4 is formed into a predetermined shape and then sintered to obtain a conductive sintered body. Using at least one compound of an indium compound, a zinc compound, and an element having a valence of three or more, a precipitate formed by a precipitation-forming agent from one or more solutions containing at least one of these compounds is solid-liquid The method for producing a conductive material according to claim 2, wherein the powder is separated, and if necessary, is calcined and reduced to obtain a conductive powder. The method for producing a conductive material according to claim 2, wherein the powder obtained in claim 6 is formed into a predetermined shape and then sintered to obtain a conductive sintered body. The method according to any one of claims 4 to 7 , wherein the powder or the sintered body is further subjected to a reduction treatment.