JP3336148B2 - Needle-like conductive antimony-containing tin oxide fine powder and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acicular conductive antimony-containing tin oxide fine powder and a method for producing the same, which is an excellent powder which can be applied in various fields of application and which can increase added value. Related to high-performance functional materials.

[0002]

2. Description of the Related Art There are various conductivity-imparting agents or antistatic agents for plastics, rubber, fibers and the like, as well as conductivity-imparting agents for supports of recording materials such as electrophotographic copying paper and electrostatic recording paper. For example, antimony-containing tin oxide spherical powder (for example, see JP-A-4-77317)
No.), conductive stannic oxide fibers (for example, see JP-A-61-17421).
), Conductive powder in which a conductive layer composed of tin oxide or tin oxide and antimony oxide is coated on the surface of titanium dioxide powder (for example, JP-A-56-41603), and fibers whose surface is covered with stannic oxide Potassium titanate (for example, JP-B-61-269)
No. 33) is known.

[0003]

By the way, the above-mentioned conductive powders of tin oxide, titanium dioxide and potassium titanate have a so-called electron conduction type conductive function, and therefore are not suitable for polymer electrolytes. Compared to the so-called ion conduction type, the stability of conductivity to humidity and temperature is high, and recently, for example, as an antistatic conductivity imparting agent for materials and products in various fields such as paints, inks, plastics, and fibers. In addition, its use as a functional material as a reinforcing filler has attracted attention, and its application is rapidly being promoted.

[0004] Usually, these conductivity-imparting agents are filled into rubber, plastics, paper, or the like, or dispersed in a solution containing a binder to form a coating solution, which is used for various films and sheets. It is used by being applied or used on a substrate such as a support, or even a casing. In order to obtain good conductivity, the powder content should be such that at least adjacent powders come into close contact with each other. Have to do more. Therefore, it is difficult to form a conductive material or a conductive layer requiring transparency using such a powder.

[0005] When a needle-like or fibrous conductivity-imparting agent is used, a small amount of the conductivity-imparting agent per unit area or unit volume can effectively form a conductive path. If metal wool, metal whiskers, or the like are used, they are all colored, and are not suitable when transparency is required.

In order to solve such a problem, conductive stannic oxide fibers have been proposed, which are thick and long with a diameter of 0.5 μm and a length of about 3 mm. It cannot be used in the required fields, and its production method is also a method of melting a raw material in an electric furnace and precipitating a fibrous material, which requires a long time and is not industrial.

However, in the application of the conductive powder as described above, recently, for example, an OHP film or a CRT
Anti-static treatment to avoid static electricity damage to windows and even IC packages and housings of electronic devices, as well as the desired conductivity-imparting ability, such as the transparent electrodes of liquid crystal displays and other EL devices, It is strongly desired that an ultra-thin conductive film can be formed substantially without light absorption on the body surface of the body.

[0008] An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide an object to be processed in various fields of application with conductivity and transparency suitable for giving the above-mentioned desired characteristics. An object of the present invention is to provide an excellent acicular conductive antimony-containing tin oxide fine powder, a method for producing the same, and a method for using the same.

[0009]

Means for Solving the Problems The present inventors have made various studies to solve the above problems in advance and to provide a conductivity-imparting agent satisfying the above-mentioned performance. The study focused on making the particles of tin fine powder acicular so as to facilitate the continuity of the particles in a medium for application applications, and to efficiently add conductivity by adding a small amount of the particles.
As a result, (1) a needle-shaped antimony-containing tin oxide fine powder having a specific long axis average particle diameter, a specific short axis average particle diameter, and an aspect ratio of not less than a specific By having it, it can be an optimal high-functional material that can provide extremely excellent conductivity and transparency, and further, surface smoothness, and this material has excellent dispersibility in water and is suitable for various uses. Being able to form an aqueous dispersion,
(2) In order to produce antimony-containing tin oxide fine powder,
In firing the tin component and the antimony component in the presence of the boron compound, the Sb / Sn ratio is set to 0.1 / 100 to
By controlling the ratio to 8/100, a fine powder having a low powder resistance value and good acicularity can be obtained, and (3) further adding a phosphorus component and calcining further improves the acicularity. The needle-shaped antimony-containing tin oxide fine powder having the optimum particle diameter of the above (1) can be produced extremely industrially and advantageously, and the one obtained by subjecting it to a soluble salt removal treatment can be used for various applications. With the knowledge that the desired electrical conductivity, transparency, and even surface smoothness, excellent performance such as adhesion, and that it can also be excellent in self-water dispersibility, the present invention, completed.

That is, the present invention provides a method of calcining a material to be calcined containing a boron compound and hydrous tin hydroxide or a dehydrate thereof containing an antimony component in advance at 700 to 1200 ° C., and then dissolving the soluble salts of the calcined product. Needle-like conductive antimony-containing tin oxide fine particles having a minor axis average particle diameter of 0.01 to 0.2 μm, a major axis average particle diameter of 0.05 to 10 μm, and an aspect ratio of 3 or more to be removed. It is a powder and its manufacturing method. In addition, the present invention is characterized in that the object to be fired containing a tin component, an antimony component, a boron compound and a phosphorus compound is fired at 700 to 1200 ° C., and then the soluble salts of the fired product are removed. 0.0
1 to 0.2 μm, and the major axis average particle diameter is 0.05 to 1
An acicular conductive antimony-containing tin oxide fine powder having a thickness of 0 μm and an aspect ratio of 3 or more, and a method for producing the same. Further, the present invention provides a fired material containing a tin component, an antimony component, a boron compound, and a silica compound,
Sintering at ℃ 1200 ° C., and then removing soluble salts of the sintering product, short axis average particle size is 0.01 to 0.2 μm
Has a major axis average particle size of 0.05 to 10 μm,
An acicular conductive antimony-containing tin oxide fine powder having an aspect ratio of 3 or more and a method for producing the same. The average particle diameter referred to here is obtained by observing an electron micrograph (magnification 100,000) to obtain a 50% weight average diameter. In addition, in the present invention, the “needle shape” includes a fiber shape, a columnar shape, a rod shape, and other similar shapes in addition to a needle shape in the range of the physical property value.

The acicular conductive antimony-containing tin oxide fine powder of the present invention is obtained by calcining a material to be calcined containing a hydrous tin hydroxide containing an antimony component or a dehydrate thereof and a boron compound, and then calcining the resultant calcined material. It can be obtained by removing the soluble salts of the product. Further, the acicular conductive antimony-containing tin oxide fine powder of the present invention is obtained by firing a material to be fired containing a tin component, an antimony component, a boron compound and a phosphorus compound, and then removing soluble salts of the obtained fired product. Can be obtained. Furthermore, the acicular conductive antimony-containing tin oxide fine powder of the present invention is obtained by firing a material to be fired containing a tin component, an antimony component, a boron compound and a silica compound, and then removing the soluble salts of the obtained fired product. Can be obtained.
Thus, in the present invention, the material to be fired is a tin component,
A substance containing an antimony component and a boron compound is mentioned. Among them, a substance not containing one or more components other than a tin component is called a precursor.

To prepare a precursor comprising a tin component and an antimony component, a powder of each compound is used,
For example, (a) a tin compound aqueous solution and an antimony compound aqueous solution, and an alkaline aqueous solution are added in parallel to hot water at 70 to 90 ° C. (B) neutralizing an aqueous solution of a tin compound and an aqueous solution of an antimony compound by adding an aqueous alkali solution to the aqueous solution of the tin compound; A method such as addition may be used. Especially among such methods
The method (a) is industrially desirable. In this case, it is preferable to maintain the pH of the neutralization reaction solution at 3 or more, preferably 5 to 10.

In the method of the present invention, it is desirable to carry out the neutralization reaction under heating or in hot water, but it is also possible to carry out the reaction at room temperature without heating. The method of adding the antimony compound to the tin oxide hydroxide or tin oxide compound is not particularly limited.

A tin component, an antimony component,
When a phosphorus compound is further added in addition to the boron compound and calcined, a compound having better needle-like properties may be obtained, which is preferable. As a method of adding the phosphorus component, an aqueous solution of a tin compound, an aqueous solution of an antimony compound, and an aqueous solution of a phosphorus compound are treated with an alkali to obtain antimony and phosphorus-containing tin hydroxide, or antimony-containing tin hydroxide, and then the phosphorus compound is added. Is added, but the method is not particularly limited to these methods.

As the tin compound used in the present invention, tin halides such as tin chloride, tin oxide, tin hydroxide or inorganic salts of tin such as tin sulfate and tin nitrate (stannic salt, tin oxide) Ditin salt) and the like, and these may be used alone or in combination of two or more. Among them, the use of an aqueous solution of tin chloride in hydrochloric acid is industrially desirable.

Examples of the antimony compound include antimony halides such as antimony chloride, antimony oxide, antimony hydroxide, and inorganic acid salts such as antimony sulfate. These may be used alone or in combination of two or more. You may. Among them, it is industrially desirable to use an aqueous solution of antimony chloride in hydrochloric acid.

As the phosphorus compound, various compounds can be used, and sodium pyrophosphate, sodium hexametaphosphate, sodium triphosphate, sodium polyphosphate, phosphorus trichloride, orthophosphoric acid, sodium hydrogen phosphate, trisodium phosphate, phosphorus Examples thereof include ammonium hydrogen oxyacid, phosphorous acid, sodium dihydrogen phosphite, sodium trihydrogen phosphite, and phosphorus pentachloride.

The mixing ratio of the tin compound and the antimony compound is 0.1 / 100 to 8 with antimony as Sb / Sn.
Sb / Sn <0.1 / 10
0, desired conductivity cannot be obtained, and Sb / Sn>
When the ratio is 8/100, a desired fine acicular powder having a short aspect and a large aspect ratio for obtaining transparency cannot be obtained.

When the phosphorus compound is added, the mixing ratio of the phosphorus compound and the tin compound is preferably 1 to 20% based on the weight of SnO ₂ in terms of P ₂ O ₅ , but is particularly limited to this. It is not something to be done.

Examples of the alkali for forming the precipitate include hydroxides, carbonates and ammonia of alkali metals such as sodium hydroxide, potassium hydroxide, sodium carbonate and potassium carbonate. You may mix and use more than one kind.

Next, the precursor obtained as described above is subjected to ordinary treatments such as washing, drying and pulverization, and is calcined at 700 to 1200 ° C. in the presence of a boron compound.

When the precursor and the boron compound are mixed, the mixing can be performed with a mixing stirrer such as a Henschel mixer. After mixing, the mixture is pulverized with a dry pulverizer to obtain a more preferable compound in terms of needle-like properties. At this time, if a phosphorus compound is added and sintering is performed, a needle having better needle-like properties may be obtained in some cases. In addition, various regulators can be added to adjust the properties of the final product. For example, a silica compound or the like can be added for the purpose of improving the water dispersibility of the acicular fine powder.

The firing can be performed at 700 to 1200 ° C., preferably 800 to 1100 ° C.
If the temperature is lower than 00 ° C., the needle-like property becomes insufficient. If the temperature exceeds 1200 ° C., the short axis becomes thick and the transparency is easily impaired. The firing time is suitably from 30 minutes to 5 hours.

Various boron compounds can be used. For example, borax (Na ₂ B ₄ O ₇ .10H)
₂ O), lithium borohydride, sodium borate, magnesium borate, potassium borate, calcium borate and the like. These may be used singly or in combination.
As the amount of the boron compound used, SnO ₂ as a precursor,
As B ₂ O ₃ on the total weight of Sb ₂ O ₃ 5~50
%, Desirably 10 to 30%. If the amount is lower than the above range, the needle shape becomes insufficient, and if the amount is too large, not only is it not economically advantageous but also the productivity is deteriorated, which is not preferable.

Next, the calcined product is treated with an aqueous medium of water or acid to remove soluble salts. Various acids can be used as the acid used here. For example, there are inorganic acids and organic acids, and among them, inorganic acids such as hydrochloric acid, sulfuric acid and hydrofluoric acid are preferable.

The treated product obtained by removing the soluble salts as described above is subjected to ordinary filtration, washing, drying, finish pulverization, etc., so that the short-axis average particle size is 0.01 to 0.1.
2 μm, the major axis average particle diameter is 0.05 to 10 μm,
Needle-like conductive antimony-containing tin oxide fine powder having an aspect ratio of 3 or more can be obtained. In addition, those having poor needle-like properties are removed by a classification means such as centrifugal sedimentation,
Needle-like properties can be further improved.

The acicular conductive antimony-containing tin oxide fine powder of the present invention is blended with a plastics, rubber, fiber, or the like as a conductivity-imparting material or a base material.
It can be used as a conductive composition such as a conductive paint, a magnetic paint, a conductive rubber, and a conductive fiber. When used as conductive plastics, various types of so-called general-purpose plastics and engineering plastics can be used. Examples of general-purpose plastics include polyethylene, vinyl chloride resin, polystyrene, polypropylene, methacrylic resin, and urea. -Melamine resin is, for example, phenolic resin, unsaturated polyester resin, hard vinyl chloride resin, ABS resin, and AS resin as engineering plastic general-purpose plastics. Engineering plastic is, for example, epoxy resin, polyacetal, polycarbonate, polybutylene. Terephthalate, polyethylene terephthalate, polyphenylene ether, polyphenylene sulfide, polysulfone, fluororesin Examples of plastics include diallyl phthalate resin, silicone resin, polyimide resin, polyamide imide, bismaleimide triazine, polyaminobismaleimide, olefin vinyl alcohol copolymer, polyoxybenzylene, polymethylpentene, polyether sulfone, and polyether. Examples include imide, polyarylate, and polyetheretherketone, which are blended with these resins. The amount of the acicular conductive antimony-containing tin oxide fine powder mixed with the molding resin is 3 to 200 parts by weight, preferably 10 to 10 parts by weight, per 100 parts by weight of the resin.
0 parts by weight.

When used as a conductive paint or a magnetic paint, various binders such as polyvinyl alcohol resin, vinyl chloride-vinyl acetate resin, acrylic resin, epoxy resin, urethane resin, alkyd resin, polyester resin, ethylene vinyl acetate copolymer Coalescing, acrylic-styrene copolymer, cellulose resin, phenolic resin, amino resin,
It is blended with a natural resin such as a fluororesin, silicone resin, petroleum resin, shellac, rosin derivative, rubber derivative and the like, and dispersed in water or a solvent. The compounding amount of the acicular conductive antimony-containing tin oxide fine powder in the binder resin is 3 to 200 parts by weight, preferably 10 to 100 parts by weight, based on 100 parts by weight of the binder solid content. In the case of a conductive paint, the paint is applied to an insulating substrate such as paper or a polymer film to form a conductive coating light on the substrate and excellent in transparency, surface smoothness, and adhesion. The film can be formed into various antistatic coatings, electrostatic recording paper, electrophotographic copying paper, and the like.

On the other hand, in the case of a coating material used for manufacturing a magnetic recording medium, the adhesive strength between the non-magnetic support and the magnetic layer is improved, the magnetic recording medium is prevented from being charged, the film strength is enhanced, and the magnetic layer is thinned. It is useful for improving the dispersibility and surface smoothness of the lower non-magnetic layer accompanying layering and surface smoothing. In particular, in recent years, the recording wavelength tends to be shortened as magnetic recording density increases,
In conjunction with this, there is a further demand for thinner magnetic layers of magnetic recording media. However, when the magnetic layer is made thinner, the influence of the support tends to appear on the magnetic surface, and deterioration of the electromagnetic conversion characteristics is inevitable. For this purpose, for example, by providing a non-magnetic undercoat layer on the surface of the non-magnetic support and then providing the magnetic layer as an upper layer, the influence of the surface roughness of the support is eliminated, and the magnetic layer is thinned to achieve a high level. A method for achieving output has been used. The filling ratio of the acicular conductive antimony-containing tin oxide fine powder of the present invention into the lower nonmagnetic layer is about 20 to 80% by volume filling rate.

When used as a conductive rubber, for example, silicone rubber, isoprene rubber, styrene-butadiene rubber, butadiene rubber, butyl rubber, butadiene-
Acrylonitrile rubber, ethylene-propylene-diethane polymer, ethylene-propylene rubber, fluoro rubber,
Ethylene-vinyl acetate copolymer, chlorinated polyethylene,
It is blended with conventionally known rubbers such as acrylic rubber, chloroprene rubber, urethane rubber, polysulfide rubber, chlorosulfonated polyethylene rubber, and epichlorohydrin rubber.

When used as a conductive fiber, it is blended with a weightable fiber such as a polyamide resin, a polyester resin, a polyolefin resin, a polyvinyl resin, and a polyether resin.

The conductive composition thus obtained is
Compared to the conductive composition containing the conventional spherical conductive powder, high conductivity can be obtained with a smaller amount of the resin binder, and the transparency is also excellent, which is economically advantageous. . Since such a small amount is sufficient, it can be used without lowering the strength of the binder. In addition, when a high-concentration conductive paint is used, desired conductivity can be obtained even with a thin coating film.

[0033]

【Example】

Example 1 A solution prepared by dissolving 500 g of stannic chloride pentahydrate and 10 g of antimony trichloride in 500 ml of a 3N hydrochloric acid solution in 5 l of pure water at 90 ° C., and sodium hydroxide were added to the system at pH 7.
A co-precipitate was formed by parallel addition over 20 minutes to maintain ~ 7.5. Next, hydrochloric acid was added thereto to adjust the pH of the system to 3, and then the precipitate was filtered and then washed with water until the specific resistance of the filtrate became 15000 Ωcm. After the obtained cake was dried at 110 ° C. for 12 hours, 136.5 g of borax was added to the dried product, and both were uniformly mixed and pulverized. This mixture was fired in an electric furnace at 900 ° C. for 1 hour. Thereafter, the obtained calcined product was immersed in an aqueous hydrofluoric acid solution to remove soluble salts, and then dried and pulverized to obtain a desired acicular conductive antimony-containing tin oxide fine powder. .

Example 2 In Example 1, the amount of antimony trichloride was changed to 3.3.
Except that the amount was changed to 6 g, the same treatment as in the same example was carried out to obtain a desired acicular conductive antimony-containing tin oxide fine powder. An electron micrograph of this is shown in FIG.

Example 3 The same procedure as in Example 2 was repeated except that 20 g of sodium pyrophosphate was added to the dried product in addition to borax to obtain the desired acicular conductive antimony. A fine powder containing tin oxide was obtained.

Example 4 In Example 2, except that 17.4 ml of a sodium silicate solution (308 g / l in terms of SiO ₂ ) was added together with stannic chloride pentahydrate, antimony trichloride and sodium hydroxide. Then, the same treatment as in the case of the same example was carried out to obtain a target fine needle-like conductive antimony-containing tin oxide fine powder.

Example 5 A desired acicular conductive antimony-containing tin oxide fine powder was obtained in the same manner as in Example 2 except that the amount of borax was changed to 32 g. Was.

Comparative Example 1 A conductive fine powder was obtained in the same manner as in Example 1, except that 33.6 g of antimony trichloride was used.

Comparative Example 2 A conductive fine powder was obtained in the same manner as in Example 2 except that borax was not used. An electron micrograph of this is shown in FIG.

Comparative Example 3 In 5 l of 90 ° C. water, 234.5 g of stannic chloride pentahydrate and 17.4 g of antimony trichloride were added in a 5N aqueous hydrochloric acid solution (50 ml).
0 ml solution and sodium silicate aqueous solution (Si
8.2 ml of O _{2 (} 308 g / l) and the pH of the system was 6
The co-precipitation of tin oxide, antimony oxide and silicon oxide hydrate was formed by parallel addition over 30 minutes to maintain ~ 7. Then add hydrochloric acid to the system
Was adjusted to 3, and the precipitate was filtered, and then washed with water until the specific resistance of the filtrate reached 10,000 Ωcm. The obtained cake is calcined at 700 ° C. for 4 hours in an electric furnace, and the calcined product is pulverized with a pulperizer to obtain a specific surface area of 75.6 m.
² / g of spherical conductive fine powder was obtained.

Test Example 1 With respect to the conductive fine powder of each sample obtained in each of the above Examples and Comparative Examples, (1) an electron micrograph (magnification 100,000) was observed to determine a weight average particle diameter. The aspect ratio was calculated based on this. Furthermore, (2) 1 of each sample powder
The specific resistance (Ωcm) under a pressure of 00 kg / cm ² was measured (digital multimeter: Model 2502A, manufactured by Yokogawa Hokushin Electric Company). Table 1 shows the results.

[0042]

[Table 1]

Test Example 2 Each of the conductive fine powders of the samples obtained in Example 2 and Comparative Example 3 was 2
0 g of an acrylic resin (Acridic A-165-45,
Solid content 45% by weight, manufactured by Dainippon Ink and Chemicals) 30.6
g, toluene-butanol mixed solution (mixing weight ratio 1:
1) After mixing with 26.4 g and 50 g of glass beads, paint shaker (Reddevil),
# 5110) and shaken for 20 minutes to prepare each mill base. Next, a predetermined amount of each of the above acrylic resin and the above toluene-butanol mixed solution was added to each mill base, followed by stirring and mixing, and the pigment concentrations (% by weight) in Table 2 were obtained.
A paint was prepared. This paint was applied to a polyester film so as to have a dry film thickness of 4 μm, and was naturally dried for 40 hours to prepare a test sheet. The surface resistivity (Ω / □) of this sheet was measured (Digital Ohm Meter: R-506, manufactured by Kawaguchi Electric Works). The haze degree (%) was measured (Haze meter: NDH-300).
A type, manufactured by Nippon Denshoku Industries). Tables 2 and 3 show these results.
Shown in

[0044]

[Table 2]

[0045]

[Table 3]

[0046]

Industrial Applicability The present invention provides a needle-shaped conductive material that requires less compounding amount than conventional conductive fine powder when obtaining the same conductivity without using special equipment or expensive raw materials. The present invention provides a conductive antimony-containing tin oxide fine powder and a method for producing the same, and the acicular conductive antimony-containing tin oxide fine powder of the present invention is a potassium titanate fiber coated with a conductive layer of tin oxide and antimony oxide. Powder resistance is remarkably lower than that of the resin composition, and when added to a resin composition or a binder, it imparts extremely excellent conductivity and also has excellent transparency.

[Brief description of the drawings]

1 is an electron micrograph (magnification: 100,000 times) showing the particle structure of the acicular conductive antimony-containing tin oxide fine powder of the present invention obtained in Example 2. FIG.

FIG. 2 is an electron micrograph (magnification: 100,000 times) showing the particle structure of the conductive fine powder obtained in Comparative Example 2.

Continuation of the front page (56) References JP-A-6-305727 (JP, A) JP-A-6-92636 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C01G 19 / 02 C01G 30/00 H01B 1/08 CA (STN)

Claims (12)

(57) [Claims] 1. Hydrous acid containing an antimony component in advance
A material to be fired containing tin or a dehydrate thereof and a boron compound is fired at 700 to 1200 ° C., and then soluble salts of the fired product are removed.
0.2 μm, and the major axis average particle diameter is 0.05 to 10 μm.
A method for producing acicular conductive antimony-containing tin oxide fine powder having a thickness of 3 μm and an aspect ratio of 3 or more. 2. Tin component, antimony component, boron compound
To be baked containing phosphorus and a phosphorus compound is 700 to 1200.
C. and then remove the soluble salts of the calcination product.
The short axis average particle size is 0.01 to 0.2 μm,
When the axial average particle diameter is 0.05 to 10 μm,
Conductive antimony-containing tin oxide having an impact ratio of 3 or more
Production method of fine powder. 3. Tin component, antimony component, boron compound
And the calcined material containing the silica compound are 700 to 120.
Baking at 0 ° C. and then removing soluble salts of the baking product
To have a short axis average particle size of 0.01 to 0.2 μm,
The long axis average particle size is 0.05 to 10 μm,
Needle-like conductive antimony-containing oxidation having a pect ratio of 3 or more
Method for producing tin fine powder. 4. The object to be baked contains an antimony component in advance.
Containing tin hydroxide or its dehydrate and boron compound
3. The method for producing a needle-like conductive antimony-containing tin oxide fine powder according to claim 2, wherein the fine powder comprises tin and a phosphorus compound . 5. The amount of the boron component in the material to be fired is defined as Sn
5 to 5 in terms of B ₂ O _{3 based on} the total weight of O ₂ and Sb ₂ O ₃
The method for producing a needle-like conductive antimony-containing tin oxide fine powder according to any one of claims 1 to 3, which is added by 50%. 6. A boron compound according to claim 1 which is borax
4. The method for producing a needle-shaped conductive antimony-containing tin oxide fine powder according to any one of the above-mentioned items . 7. The method according to claim 1 , wherein the short-axis average particle diameter obtained by the method according to any one of claims 1 to 3 is 0.01 to 0.2 μm, and the long-axis average particle diameter is 0.05 to 10 μm. An acicular conductive antimony-containing tin oxide fine powder having an aspect ratio of 3 or more. 8. The fine acicular conductive antimony-containing tin oxide powder according to claim 7, wherein the antimony component is 0.1 / 100 to 8/100 as Sb / Sn. 9. An aqueous dispersion obtained by dispersing the acicular conductive antimony-containing tin oxide fine powder according to claim 7 in an aqueous medium. 10. A conductive coating composition comprising 3 to 200 parts of the acicular conductive antimony-containing tin oxide fine powder according to claim 7 based on 100 parts by weight of a binder solid content. 11. Use of the aqueous dispersion according to claim 9,
3 to 2 in solid content based on 100 parts by weight of binder solid content
A conductive coating composition comprising 00 parts. 12. A conductive resin composition comprising the acicular conductive antimony-containing tin oxide fine powder according to claim 7 in an amount of 3 to 200 parts by weight based on 100 parts by weight of a molding resin.