JPH0353728B2 - - Google Patents

Description

[Detailed description of the invention]

TECHNICAL FIELD OF THE INVENTION The present invention relates to a coating liquid for forming a transparent conductive film and a method for producing the same. Highly sexual,
The present invention relates to a coating solution for forming a transparent conductive film and a method for producing the same, which enables continuous production of extremely transparent conductive films at low temperatures of 150°C or higher. Technical background of the invention and its problems Glass and plastic are transparent base materials and are used for various purposes, but because they are insulators, they tend to generate static electricity on their surfaces. When these are used as front base materials for display devices such as cathode ray tubes (CRTs) and liquid crystal displays (LCDs), dirt and dust may adhere to them, making it difficult to see the image, and in electronic displays such as LCDs, they may malfunction. There is also a risk of it happening. Furthermore, in a copying machine 1 equipped with an automatic document feeder (ADF) as shown in FIG. 1, static electricity is generated on the top glass 2 while documents are being fed, which causes paper jams and prevents continuous feeding of documents. It's gone,
Furthermore, when the original is moved over the top glass 2 by the ADF, it scratches the top glass 2, which impairs its transparency, resulting in problems such as a lack of sharpness in the resulting copied image. Furthermore, plastic substrates have low surface hardness and are easily scratched, reducing the transparency of the substrate. In order to solve these problems, for example, on a substrate such as glass or plastic,
Methods of forming metal thin films or conductive inorganic oxide films using vapor phase methods such as CVD, PVD, and vapor deposition are being studied. However, although these films have excellent transparency and conductivity, they have a problem in that they have low alkali resistance and are easily scratched due to poor scratch resistance. In addition, vacuum evaporation equipment is required to form these films, and this equipment limits the area or shape of the substrate on which the film can be formed. Furthermore, it cannot be formed at low temperatures, and it requires a batch process. Therefore, continuous productivity was poor. In order to solve the problem, there is also a method of applying a conductive paint, in which a conductive substance is dispersed in a binder resin such as acrylic resin, vinyl resin, amine resin, or melamine resin, to the surface of the substrate. It is being considered. However, films obtained using conductive paints in which a conductive substance is dispersed in a binder resin have excellent conductivity, but are inferior in transparency, alkali resistance, scratch resistance, and adhesion. . By the way, the present applicant has previously filed a patent application filed in 1983-
No. 299686 discloses a coating solution for forming a conductive film in which a zirconium oxy salt, a silicon alkoxide or its derivative, and a conductive substance are uniformly dispersed in water or an organic solvent, or a coating solution in which non-sedimentable silica is mixed with the coating solution. suggested liquid. A coating film is formed on the substrate using these coating solutions, and this coating film is coated at 250°C.
Films obtained by firing at temperatures above ℃ are excellent in transparency, conductivity, scratch resistance, etc., but if the temperature during firing is below 250℃, the alkali resistance of the resulting film is poor. The present inventors found that this decreases. Therefore, it has been difficult to apply the above-mentioned coating liquid for forming a conductive film to plastics. Furthermore, due to the low thermal stability of the coating solution, the coating solution gels during coating, especially during continuous production using transfer printing, making continuous production impossible. It was my fault.
Moreover, the inventor discovered that there is a problem in that the coating solution must be kept at 15°C or lower when stored for a long period of time, and it is desired to solve these problems. There is. Purpose of the Invention The present invention is intended to solve the above-mentioned problems, and is to apply a material to the surface of a substrate such as glass or plastic that has excellent adhesion to the substrate, has high alkali resistance and scratch resistance, and has extremely high alkali resistance and scratch resistance. The object of the present invention is to provide a coating solution for forming a transparent conductive film and a method for producing the same, which allows continuous production of a transparent conductive film without baking at high temperatures. Summary of the Invention The coating liquid for forming a transparent conductive film according to the present invention comprises bisacetylacetonatodialkoxyzirconium, a partial hydrolyzate of silicon alkoxide,
It is characterized in that the conductive substance is uniformly dispersed in a mixed solvent consisting of water and an organic solvent. In this coating solution for forming a transparent conductive film, the agglomeration of the conductive substance and gelation due to heat are prevented by adding bisacetylacetonato-dialkoxyzirconium, and the dispersibility of the conductive substance is improved, thereby obtaining the desired result. The transparency of the coatings produced has improved, and continuous production of coatings has become possible. Furthermore, since the coating liquid for forming a transparent conductive film according to the present invention contains a partial hydrolyzate of silicon alkoxide, it has excellent adhesion to the substrate and can form a film at a low temperature of about 150°C. , a coating with excellent alkali resistance and scratch resistance can be obtained. Further, the method for producing a coating liquid for forming a transparent conductive film according to the present invention includes adding bisacetylacetonato-dialkoxyzirconium to a mixture of water and an organic solvent in which a conductive substance is dispersed, and then adding a partially hydrolyzed silicon alkoxide to a mixture of water and an organic solvent in which a conductive substance is dispersed. It is characterized by being mixed and uniformly dispersed. DETAILED DESCRIPTION OF THE INVENTION The coating solution for forming a transparent conductive film and the method for producing the same according to the present invention will be specifically described below. The coating liquid for forming a transparent conductive film according to the present invention includes bisacetylacetonatodialkoxyzirconium, a partial hydrolyzate of silicon alkoxide,
A conductive substance is uniformly dispersed in a mixed solvent consisting of water and an organic solvent, and each component will be explained below. The bisacetylacetonato-dialkoxyzirconium may have an alkoxy group having 1 to 8 carbon atoms, and a butoxy group is particularly preferred. In the coating solution for forming a transparent conductive film according to the present invention, bisacetylacetonato-dialkoxyzirconium plays a role in improving the dispersibility and thermal stability of the conductive substance, but it acts as a protective colloid for the conductive substance. It is assumed that this is because it plays a role. Silicon alkoxide has 1 to 8 carbon atoms.
SiH _a (OR) _b having 1 to 4 alkoxy groups
(a=0-3, b=1-4, a+b=4, R is an alkyl group), or (R'O) _a Si(OR) _b or R' _a
Si(OR) _b (a=1~3, b=1~3, a+b=
4, R and R' are alkyl groups), condensates thereof (up to pentamer), or derivatives in which a part of H in the above formula is substituted with Cl, a vinyl group, etc. are used. Among these, especially Si
(OR) ₄ (R is a methyl group, an ethyl group, a propyl group,
butyl group) is preferred. Furthermore, it is possible to use one kind or a mixture of two or more kinds of compounds represented by the above formula. As conditions for partial hydrolysis, general methods for partially hydrolyzing silicon alkoxide can be adopted, such as mixing silicon alkoxide with methanol or ethanol and adding water and acid or alkali to perform partial hydrolysis. Although any conditions can be adopted, the following conditions are particularly preferred.
That is, using hydrochloric acid, nitric acid, phosphoric acid, and acetic acid as acids, the mixing ratio of acid and silicon alkoxide is as follows:
0.01≦acid/SiO ₂ ≦0.5 (silicon alkoxide
(weight ratio when converted to SiO ₂ ). If this value is less than 0.01, a large amount of unreacted silicon alkoxide will be present, which will inhibit the conductivity of the resulting film, which is undesirable, and if it exceeds 0.5,
This is not preferable because the rate of partial hydrolysis becomes too high, resulting in decreased continuous productivity and storage stability of the coating solution. Further, the mixing ratio of water is preferably H ₂ O/silicon alkoxide≧2 (molar ratio).
If this value is less than 2, unreacted silicon alkoxide remains in the coating, which deteriorates adhesion, scratch resistance, and alkali resistance, which is not preferable. The partial hydrolysis temperature is preferably 30 to 60°C. As the conductive substance, tin oxide, tin oxide doped with antimony, phosphorus, fluorine, etc., indium oxide, or indium oxide doped with tin or fluorine is used, and the average particle size of these conductive substances is The diameter is preferably 0.4 μm or less. Such fine particles are described in the "Method for Manufacturing Conductive Fine Powder" (patent application filed by the applicant), which was previously filed by the applicant.
62-51008) is preferred.
(Hereinafter, the fine particles obtained based on this patent application No. 62-51008 will be referred to as the first fine particles.) In addition, for applications that require particularly low haze and high transparency, the average particle size is 0.01~ 0.1 μm conductive fine particles are optimal. Such fine particles can be produced, for example, in the patent application “Tin oxide sol and method for producing the same” (Japanese Patent Application No. 75283/1983) previously filed by the present applicant.
obtained based on. (Hereinafter referred to as this patent application No. 61-75283)
(The fine particles obtained based on the above-mentioned method are referred to as second fine particles.) First, the method for manufacturing the first fine particles will be explained. First, the first fine particles are produced by heating an aqueous solution containing a tin compound or an indium compound under a pH condition of 8 to 12. By holding and gradually hydrolyzing the tin or indium compound, a sol containing colloidal particles of metal oxide, hydrous oxide, or metal oxide was produced, and this sol was then dried and calcined. After that, it is obtained by crushing. As a starting material, a tin compound or an indium compound that is water-soluble and can be hydrolyzed within a pH range of 8 to 12 is used. Specifically, tin compounds such as potassium stannate and sodium stannate, and Indium compounds such as indium nitrate and indium sulfate are used. When the metal species contained in the aqueous solution containing a tin compound or an indium compound (hereinafter referred to as raw material liquid) is either tin or indium, the obtained first fine particles are composed of tin oxide or indium oxide. However, by dissolving a small amount of a different element in the raw material liquid, first fine particles doped with a different element can be manufactured. For example, by dissolving a small amount of tartarite or ammonium fluoride in a raw material solution containing a tin compound, it is possible to obtain first fine particles in which tin oxide is doped with antimony or fluorine. By dissolving a small amount of a tin compound in the raw material liquid, it is possible to obtain first fine particles in which indium oxide is doped with tin. The first fine particles doped with a different element can also be produced by the following method. That is, an aqueous solution of a tin compound is used as the raw material liquid, and the tin compound in the liquid is gradually hydrolyzed under the above PH conditions to generate a sol, and colloidal particles are collected from this sol. Tin oxide is doped with antimony, phosphorus, fluorine, etc. by impregnating the colloidal particles with an aqueous solution of at least one of an antimony compound, a phosphorus compound, and a fluorine compound, and then drying and calcining the particles. It is possible to produce the first fine particles. In addition, an aqueous solution of an indium compound is used as the raw material liquid, and a sol is generated in the same manner as above.
After collecting the colloidal particles from this sol, the colloidal particles are impregnated with an aqueous solution of a tin compound and/or a fluorine compound, and then the particles are dried and fired. The first doped with fluorine
Fine particles can be produced. In this case, if by-product salt is generated in the process of generating a sol, not only will the colloid particles be more likely to aggregate, but the resistivity of the first fine particles finally obtained will be lowered due to the contamination of the by-product salt. Therefore, if the formation of by-product salt is expected, the colloidal particles recovered from the sol,
It is recommended that by-product salts be removed from colloidal particles prior to impregnation with an aqueous solution of an elemental compound for doping. The concentration of the tin compound or indium compound contained in the raw material liquid can be arbitrarily selected, but
Generally, a range of 0.5 to 30% by weight is preferred. When hydrolyzing the tin compound or indium compound contained in the above-mentioned raw material liquid together with the compound of a different element as a dopant if it coexists, the pH of the reaction system should be set to 8 to 12.
must be held at an arbitrary constant value within the range of . If the pH of the reaction system is less than 8, the particle size distribution becomes broad, and if the pH value further decreases, metal oxides generated by hydrolysis precipitate and are dispersed in the liquid as colloidal particles. Therefore, it is not possible to prepare a sol, which is not preferable. In addition, if the pH of the reaction system exceeds 12, although it is not impossible to prepare a sol, the alkali content cannot be sufficiently removed when washing the colloid particles filtered from the sol, resulting in This is not preferable because the conductivity of the first fine particles obtained is deteriorated. There are no particular restrictions on the solids concentration of the sol produced in the reactor, but generally, as the concentration increases, the particle size distribution of the colloid particles produced tends to become broader. The reaction temperature for hydrolysis can be arbitrarily selected, usually in the range of 30 to 90°C. The average particle size of colloidal particles obtained by hydrolysis is 0.05 to 0.3 μm, preferably 0.07 to 0.3 μm.
It is in the range of 0.2 μm, and the particle size distribution is 80% of all particles.
The above range is 0.5 to 1.5 times the average particle size. After the sol is prepared, the sol is filtered to collect colloidal particles, washed to remove by-product salts and other particles adhering to the particles, dried, further calcined, and pulverized. First fine particles can be obtained. Since the particles filtered from the sol are slightly sintered in the firing process, the average particle size of the first fine particles is usually about 20 to 50 μm, and the specific surface area of the first fine particles is usually 100 m ² /g or less. It is. The first fine particles obtained in this way are also
The sintered state can be easily released by pulverization, and first fine particles having an average particle size of 0.4 μm or less in the coating liquid can be obtained by ordinary pulverization means. The first fine particles thus obtained contain only a small amount of coarse particles of 0.8 μm or more. The first fine particles may be pulverized before or after mixing with other components such as silicon alkoxide. The first fine particles can be pulverized by a conventionally known pulverization method, and for example, equipment such as an attritor, a sand mill, a ball mill, and a three-roll mill can be used. Next, to explain the second fine particles, this second fine particle
The fine particles are fine particles dispersed in a conductive tin oxide colloid obtained by heat-treating tin oxide or fine powder of tin oxide doped with a different element in an aqueous acid solution or aqueous alkaline solution. The fine powder of tin oxide or different element-doped tin oxide used here is one that has been fired at a high temperature in order to impart conductivity, and may be obtained by the method for producing the first fine particles, or may be one obtained by the conventionally known method for producing the first fine particles. It may be obtained by a method. This conductive tin oxide colloid can be obtained in the following manner. That is, the tin oxide or the fine powder of tin oxide doped with a different element is heat-treated in an aqueous solution of an acid such as a mineral acid or an organic acid, or an aqueous alkali solution of an alkali metal hydroxide or quaternary ammonium. Preferably, the heating temperature is about 200°C or less. The amount of acids and alkalis should also be at least 5% by weight of the fine powder to be treated.
It is preferable that it is above. The colloidal particles in the conductive tin oxide colloid thus obtained usually have an average particle size of 0.1 μm or less, with more than 60% of all particles being 0.1 μm.
It is dominated by particles smaller than m. When the conductive substance of the first fine particles or second fine particles thus obtained is a powder, it can be used as it is, or it can be used after being dispersed in water or an organic solvent. The conductive tin oxide colloid in which the second fine particles are dispersed is an aqueous sol using water as a dispersion medium, but it can also be used as it is, or if necessary, some or all of the water can be replaced with an organic solvent such as alcohol. It can also be used as an organic sol substituted with Next, the organic solvent used in the coating solution for forming a transparent conductive film of the present invention is explained. Examples of this organic solvent include alcohols such as methanol, ethanol, propanol, and butanol, and esters such as methyl acetate and ethyl acetate. , ethers such as diethyl ether, ketones such as acetone, methyl ethyl ketone, ethyl cellosolve, etc. may be used singly or in combination of two or more. In the coating solution for forming a transparent conductive film of the present invention, the bisacetylacetonato-dialkoxyzirconium and the conductive substance have a weight ratio of 0.01≦ZrO ₂ /MO _x ≦1 in terms of their respective oxides. Preferably, it is used in amounts (MO _x is the electrically conductive substance expressed as an oxide). If this value is less than 0.01, the dispersibility and thermal stability of the conductive substance will decrease, the resulting film will have poor transparency and adhesion, and the storage stability and continuous productivity of the coating solution will deteriorate. Therefore, it is undesirable. Moreover, if the above value exceeds 1, the transparency and adhesion of the obtained film will deteriorate and the conductivity will decrease, which is not preferable. Also, bisacetylacetonatodialkoxyzirconium,
The silicon alkoxide is preferably used in an amount such that 0.01≦ZrO ₂ /SiO ₂ ≦1 in terms of weight ratio of each oxide. This value
If it is less than 0.01, the alkali resistance of the coating will not be sufficient, while if it exceeds 1, adhesion and transparency will decrease, which is not preferable. Furthermore, the weight ratio of the conductive substance in terms of oxide is
It is preferable to use an amount that satisfies 0.5≦MO _x /(SiO ₂ +ZrO ₂ )≦5. This value is 0.5
If it is less than 5, the conductivity will not be sufficient, and if it exceeds 5, the adhesion, transparency, and scratch resistance will deteriorate, which is not preferable. If the solid content concentration (MO _x +SiO ₂ +ZrO ₂ ) of the coating liquid for forming a transparent conductive film of the present invention is 15% by weight or less, a film that meets the purpose of the present invention can be obtained. If the above solid content concentration exceeds 15% by weight, the storage stability of the coating solution will deteriorate, which is not preferable. Furthermore, if the solid content concentration is too low, it will be necessary to repeat the coating operation several times to obtain the desired film thickness, so it is practical that the solid content concentration is 0.1% by weight or more. Next, the method for producing the coating liquid for forming a transparent conductive film according to the present invention will be explained. It is manufactured by adding a partial hydrolyzate of silicon alkoxide after adding nato-dialkoxy zirconium to improve the dispersibility and thermal stability of the conductive material. It is not preferable to add silicon alkoxide before adding bisacyl acetonate-dialkoxyzirconium because the conductive material will aggregate. In the coating solution for forming a transparent conductive film of the present invention produced in this manner, the conductive substance is first maintained in a monodisperse state due to the protective colloidal action of bisacetylacetonatodialkoxyzirconium. Excellent dripping, film transparency and conductivity. Secondly, stability is improved, so during continuous production,
The coating solution does not gel, and can be stored for long periods at room temperatures of around 30°C. In addition, the bisacetylacetonato-dialkoxyzirconium forms a matrix of the film together with the partial hydrolyzate of silicon alkoxide, and increases the scratch resistance and alkali resistance of the film. Due to the presence of hydrolyzate, approx.
A film can be formed by firing at a temperature of about 150°C, and a film with further improved conductivity can be obtained by firing at a temperature of 200°C or higher. To form a film using the coating liquid for forming a transparent conductive film of the present invention, conventionally known coating methods can be used, such as a spinner method, a spray method, a barcode method, etc. , transfer printing method, etc. are most suitable. For example, if a roll coater is used, continuous production of 20,000 sheets or more is possible. The film obtained by applying the coating liquid for forming a transparent conductive film according to the present invention to a base material such as glass or plastic has excellent transparency with a total light transmittance of 90% or more and a haze of 5% or less. Conductivity and surface resistance
It is excellent at 10 ³ to 10 ¹⁰ Ω/□. Furthermore, since it has high scratch resistance and alkali resistance, it can be used in applications where the coating is abraded or affected by alkali.
Therefore, the substrate provided with the coating formed from the coating liquid for forming a transparent conductive film according to the present invention has excellent antistatic properties, and can be used, for example, as a front base material for CRT and LCD display devices, and for copying devices equipped with ADF. machine top glass,
Used for instrument panels, transparent digitizers, telewriting terminals, etc. Effects of the Invention The coating solution for forming a transparent conductive film of the present invention improves the dispersibility and thermal stability of the conductive substance by adding bisacetylacetonatodialkoxyzirconium to a mixture of water and an organic solvent in which a conductive substance is dispersed. After improving the temperature, a partial hydrolyzate of silicon alkoxide is added and uniformly dispersed. Therefore, 30
It has excellent stability even at room temperatures of about 150°C and can be stored for long periods of time.Moreover, the conductive film formed using this coating solution can be produced continuously, and if fired at temperatures above 150°C, , transparency, conductivity,
A film with excellent adhesion, scratch resistance, and alkali resistance can be obtained. EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples. Example [Preparation of partial hydrolyzate of silicon alkoxide] Solution A Ethyl silicate-28 (manufactured by Tama Chemical Industries), 100
While stirring the mixture, 110 g of ethanol was added, and 70 g of a 2.5% by weight aqueous nitric acid solution was further added. The mixture was then heated to 60°C and held for 1 hour. B liquid Ethyl silicate-40 (manufactured by Tama Chemical Industry), 100
While stirring the mixture, 200 g of ethanol was added, and 100 g of a 1.0% by weight acetic acid aqueous solution was further added. The mixture was then heated to 40°C and held for 30 minutes. [Preparation of conductive substance] Solution C: 316 g of potassium stannate and 38.4 g of tartarite, 686 g of water
A raw material solution was prepared by dissolving it in g. The above raw material solution was added to 1000 g of water heated to 50° C. and stirred over 12 hours together with nitric acid, and the pH in the system was maintained at 8.5 for hydrolysis to obtain a sol. After filtering the colloidal particles from this sol and washing to remove by-product salts, the particles are dried and calcined in the air at 350℃ for 3 hours, and further calcined in the air at 650℃ for 2 hours to form a fine powder. ) was obtained. 20g of this fine powder () in 100ml of water
g, and ground in a sand mill for 3 hours to obtain a dispersion with an average particle size of 0.3 μm. The average particle size of the particles was determined by adjusting the solid content concentration in the measurement sample to 0.5% by weight using an ultracentrifugal particle size analyzer (manufactured by Horiba, CAPA-500).
It was measured by centrifugal sedimentation at 5000 rpm. Solution D: 400 g of fine powder () was added to 1,600 g of 2.5% by weight potassium hydroxide, and the mixture was stirred in a sand mill for 3 hours while maintaining it at 30° C. to obtain a sol in which tin oxide colloid was dispersed. This sol was then treated with an ion exchange resin to obtain a dealkalized sol. The average particle size of this colloid is 0.07 μm.
Particles with a diameter of 0.1 μm or less accounted for 87% of all particles. Solution E A solution of 79.9 g of indium nitrate dissolved in 686 g of water and a solution of 12.7 g of potassium stannate dissolved in a 10% by weight aqueous potassium hydroxide solution were prepared. The above indium nitrate solution and potassium stannate solution were added over 2 hours to 1000 g of water heated to 50°C and stirred, and the PH in the system was maintained at 11 for hydrolysis to obtain a sol. . Colloidal particles are filtered from this sol, washed to remove by-product salts, dried, and calcined in air at 350°C for 3 hours.
A fine powder () was obtained by firing at 600°C for 2 hours. 20 g of this fine powder () was dispersed in 100 g of water and ground in a sand mill for 3 hours to obtain a dispersion having an average particle size of 0.3 μm. Example 1 11.9 g of ethanol was added to 100 g of Solution D, and while stirring, 3.1 g of 13% by weight diacetylacetonato-dibutoxyzirconium (ABZ) was added.
Next, 70 g of liquid A was added and thoroughly dispersed. Examples 2 to 6 and Comparative Example 1 The same procedure as Example 1 was carried out except that the composition was changed to that shown in Table 1. Comparative Example 2 11.9 g of ethanol was added to 100 g of Solution D, and while stirring, 70 g of Solution A was added. Then 13% by weight
3.1 g of ABZ was added and dispersed, but after a few minutes, colloidal particles agglomerated and precipitated. Comparative Example 3 Add 35.7g of ethyl silicate 28 while stirring.
447.3 g of ethanol was added, and further 4 g of a 25% by weight aqueous zirconyl nitrate solution and 22 g of water were added. Next, 100 g of Solution D was added and thoroughly dispersed. The thus obtained coating liquid for forming a transparent conductive film was applied to the substrates shown in Table 2 by a spinner method or a roll coater method, and baked to form a film. This film was evaluated as follows. Evaluation method Surface resistance (R _s ): Evaluated using Highrester or Lowrester (manufactured by Mitsubishi Yuka Co., Ltd.). Transparency: Total light transmittance (Tt) and haze (H) were measured using a haze computer (manufactured by Suga Test Instruments). Glossiness: Glossiness (G) was measured at a measurement angle of 60°C according to the glossiness measurement method of JIS K7105-81. Adhesion: A part of commercially available cellophane tape with a width of 12 mm was pasted on the film, the rest was held perpendicular to the film, and it was instantly peeled off, and the presence or absence of the film was visually observed. Scratch resistance: PC with a coating formed on the platform scale
(Polycarbonate plate) or glass plate is fixed, an office eraser (No. 50-50 made by LION) is placed on the coating, a load of 2 kg is applied, and the total light transmittance and surface resistance after rubbing 300 times. was measured. Alkali resistance: After soaking in 15% by weight aqueous ammonia at room temperature for one week, adhesion and surface resistance were measured. The results are shown in Table 2.

[Table] 3. Meticello = methyl cellosolve.
4. Zirco nitrate = zirconyl nitrate.
5. ES-28 = ethyl silicate-28.
6. Weight ratio of BuOH/MeOH, EtOH/methicello = 1/1
.

[Table] In Comparative Example 1, the formed film became white and Tt,
Unable to measure H and G. Also, due to poor adhesion,
Scratch resistance and alkali resistance were not measured. The coating solution of Comparative Example 2 could not form a coating film because the tin oxide colloid in the coating solution coagulated and precipitated.
PC = polycarbonate board. Glass = glass plate.
The rotation speed of the spinner is 2000 rpm.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a copying machine using a substrate coated with a coating liquid for forming a transparent conductive film according to the present invention. 1...copy machine, 2...top glass.

Claims (1)

[Claims] 1. A bisacetylacetonatodialkoxyzirconium, a partial hydrolyzate of silicon alkoxide, and a conductive substance are uniformly dispersed in a mixed solvent consisting of water and an organic solvent. A coating liquid for forming a transparent conductive film. 2. A transparent conductive material characterized by adding bisacetylacetonatodialkoxyzirconium to a mixture of water and an organic solvent in which a conductive substance is dispersed, and then mixing a partial hydrolyzate of silicon alkoxide and uniformly dispersing the mixture. A method for producing a coating liquid for film formation.