CN1627449A - Transparent conductive film-forming liquid and method for producing transparent conductive film-adhering substrate containing the same - Google Patents

Abstract

The invention provides a transparent conductive film forming liquid for forming a transparent conductive film with extremely uniform sheet resistance value and transparency. The present invention also provides a method for manufacturing a transparent conductive film-attached substrate having a transparent conductive film with extremely uniform sheet resistance and transparency. Specifically, a transparent conductive film forming liquid characterized by containing a compound represented by the formula [1 ] and a method for producing a transparent conductive film-attached substrate using the transparent conductive film forming liquid are provided]An indium compound represented by the formula [2 ]]The tin compound represented by the formula [1 ] may optionally be dissolved]An indium compound represented by the formula [2 ]]Beta-diketones of the tin compounds represented by: in ¹COCHCOR²)₃[1]Wherein R is¹And R²Each independently represents an alkyl group having 1 to 10 carbon atoms or a phenyl group; ³)₂Sn(OR⁴)₂[2]Wherein R is³Represents an alkyl group having 1 to 10 carbon atoms, R⁴Represents an alkyl group having 1 to 10 carbon atoms or an acyl group having 1 to 10 carbon atoms.

Description

Method for producing transparent conductive film-forming liquid and transparent conductive film-adhering substrate containing the same

technical field

The present invention relates to a transparent conductive film-forming liquid and a method for producing a transparent conductive film-attached substrate containing the transparent conductive film-forming liquid.

Background technique

Transparent conductive film (ITO film) is widely used in liquid crystal displays, electroluminescent displays, surface heaters (surface heaters), contact (タッチpanel) electrodes, solar cells, etc. by virtue of its excellent transparency and conductivity .

Since transparent conductive films are so widely used in many fields, they are required to have various sheet resistance values and transparency depending on the purpose of use. For example, the transparent conductive film used in flat panel displays requires a film with low resistance and high transmittance, and the transparent conductive film used in touch panels requires a film with high resistance and high transmittance. In particular, transparent conductive films for writing input touch panels that have been developed in recent years and whose market demand has increased require the film to have high position recognition precision, so high-resistance films with a sheet resistance of 200 to 3000 Ω/□ are urgently needed. This sheet resistance value is a value obtained by using the specific resistance/film thickness of the conductive film.

The method for forming the above-mentioned transparent conductive film having a desired sheet resistance value includes, for example, the sputtering method, electron beam method, After the ion plating method or chemical vapor growth method forms the transparent conductive film, the method of heat-treating the transparent conductive film in the presence of a certain concentration of organic solvent. In said publication, indium compounds such as indium triacetylacetonate, indium tribenzoylmethyl, indium trichloride, indium nitric acid, etc. Indium, indium triisopropoxide, etc.; tin compounds, such as: tin chloride, dimethyl tin dichloride, dibutyl tin dichloride, tetrabutyl tin, stannous octoate, Dibutyltin maleate, dibutyltin acetate, dibutyltin diacetylacetonate, etc. In addition, the following solvents are also exemplified, including ketone solvents such as acetylacetone, acetone, methyl isobutyl ketone, and diethyl ketone; alcohol solvents such as methanol, ethanol, propanol, isopropanol, butanol, etc. Ester solvents such as ethyl acetate and butyl acetate; ether solvents such as methyl cellosolve and tetrahydrofuran; aromatic hydrocarbons such as benzene, toluene and xylene; fatty acids such as hexane, heptane, octane and cyclohexane Hydrocarbons, etc.

However, in the above-mentioned gazette, although a method for obtaining a transparent conductive film having a desired resistance value is disclosed, how is the combination of the indium compound and the tin compound as the raw material or how is the solvent thereof preferably used for the combination, and in its specific combination The relationship between the sheet resistance value and the uniformity of transparency in transparent conductive films has not been studied. The inventors of the present invention considered how to further improve the uniformity of sheet resistance and transparency in consideration of the wide application of transparent conductive films in the future, especially ITO films.

Especially in the field of liquid crystal displays or organic EL displays, if an alkali metal is contained in an organic compound constituting a light-emitting element such as a liquid crystal or an organic EL, the reliability of the light-emitting element will be affected. Therefore, when making a light-emitting element , it is desirable to remove as much alkali metal as possible.

When making a light-emitting element, for example, when using a cheap soda-lime substrate (SLG substrate for short) as the substrate (glass substrate) of the transparent conductive film, the alkali metal of the substrate itself diffuses into the organic compound constituting the light-emitting element, which significantly reduces the To improve the reliability of the device, in order to prevent this, a silicon oxide film ( _SiO2 film) is used as an undercoat film to suppress the diffusion of alkali metals, but when the transparent electrode film formed on the _SiO2 film itself contains alkali metals, The alkali metal diffuses into the light-emitting element, and as a result, the SiO ₂ film cannot function. Therefore, there is an urgent need to prevent the reduction in the reliability of light-emitting elements due to alkali metals.

The film-forming method of the transparent conductive film further includes a physical film-forming method such as a sputtering method using a physical phenomenon in a vacuum and a chemical film-forming method such as a dipping method using a chemical reaction.

However, when the film is formed on a substrate with a curved surface or a concave-convex shape, if a physical film-forming method such as the sputtering method is used, the physical film-forming method starts to vapor-deposit and form a film from one direction of the substrate, which is very difficult. It is difficult to form a transparent conductive film with a uniform thickness on a curved portion or a concave-convex portion. Specifically, for example, when forming a transparent conductive film on a quartz fiber, when using physical film-forming methods such as sputtering, the quartz fiber must be rotated to make the film thickness uniform during film formation, but its rotational speed control is very difficult, and It is also difficult to form a transparent conductive film with a uniform film thickness.

In the dipping method, one of the chemical film-forming methods, the transparent conductive film-forming liquid can be evenly coated on the substrate with a curved surface or a concave-convex shape, but in the next step of thermal decomposition and drying, it is difficult to remove evenly Without a solvent, it is difficult to form a transparent conductive film with a uniform film thickness. Therefore, it is necessary to develop a method that can form a transparent conductive film with a uniform film thickness on a substrate with a curved surface or a concave-convex shape.

Contents of the invention

The present invention is in view of such a situation, and its object is to provide a transparent conductive film forming liquid and a method for manufacturing a transparent conductive film attachment substrate, the transparent conductive film can form a transparent conductive film with extremely uniform sheet resistance and transparency. film; the transparent conductive film attached to the substrate has a transparent conductive film with extremely uniform sheet resistance and transparency.

The purpose of the present invention is also to provide a transparent conductive film forming liquid and a method for manufacturing a transparent conductive film attachment base, the transparent conductive film forming liquid can form a transparent conductive film that can improve the reliability of the light-emitting element. The method can easily manufacture a transparent conductive film-attached base capable of improving the reliability of a light-emitting element.

Another object of the present invention is to provide a method for manufacturing a transparent conductive film-attached substrate, which can easily form a transparent conductive film with an extremely uniform film thickness on a substrate with a curved surface or a concave-convex shape.

The inventors of the present invention have studied to form a transparent conductive film with more uniform film quality. As a result, they have found that an indium compound represented by the formula [1] described later is used as the indium compound contained in the transparent conductive film forming liquid for forming a transparent conductive film. The indium compound uses the tin compound shown in the following formula [2] as the tin compound, and uses the β-diketone compound as the solvent for dissolving the above-mentioned compound, so that a transparent conductive film with more uniform film quality can be formed, thereby completing the present invention. invention.

In addition, the inventors of the present invention have repeatedly studied how to improve the reliability of light-emitting elements in technical fields such as liquid crystal displays and organic EL displays. When the content is set at a specific amount (2 mass ppm) or less, the reliability of the light-emitting device can be greatly improved, and the present invention has been completed.

In addition, the inventors of the present invention have intensively studied a method for uniformly forming a transparent conductive film on a substrate having a curved surface or unevenness, and found that it is possible to form a transparent conductive film on a substrate having a curved surface or unevenness by using a high-temperature sol treatment method (Pyrol prosess method). Uniform film formation on the surface, thereby completing the present invention. That is, in the high-temperature sol treatment method, the transparent conductive film forming liquid is formed into droplets by ultrasonic waves, and air or the like is used as a carrier to put it into a heated film forming furnace, and the transparent conductive film forming liquid in a uniform gas state sneaks into the substrate. , through contact and thermal decomposition, a transparent conductive film with a uniform film thickness can be formed even on curved or uneven parts,

That is, the present invention relates to a transparent conductive film forming liquid characterized in that it contains an indium compound represented by the following formula [1] and a tin compound represented by the following formula [2]:

In(R ¹ COCHCOR ² ) ₃ [1]

Wherein, R ¹ and R ² independently represent an alkyl or phenyl group with 1-10 carbon atoms;

(R ³ ) ₂ Sn(OR ⁴ ) ₂ [2]

Wherein, R ³ represents an alkyl group with 1-10 carbon atoms, R ⁴ represents an alkyl group with 1-10 carbon atoms or an acyl group with 1-10 carbon atoms (claim 1); the present invention also relates to the rights The liquid for forming a transparent conductive film according to claim 1, wherein the solvent for dissolving the indium compound represented by the formula [1] and the tin compound represented by the formula [2] is a β-diketone compound (claim 2). The present invention also relates to the transparent conductive film-forming solution according to claim 1, characterized in that the amount of the alkali metal contained is 2 mass ppm or less (claim 3).

In addition, the present invention relates to a method for manufacturing a substrate for attaching a transparent conductive film, which is a method for manufacturing a substrate for attaching a transparent conductive film by forming a transparent conductive film on the substrate directly or through an intermediate film, characterized in that, on the substrate or the intermediate film , using a transparent conductive film forming solution containing an indium compound represented by the following formula [1] and a tin compound represented by the following formula [2], a transparent conductive film is formed by chemical thermal decomposition:

In(R ¹ COCHCOR ² ) ₃ [1]

Wherein, R ¹ and R ² independently represent an alkyl or phenyl group with 1-10 carbon atoms;

(R ³ ) ₂ Sn(OR ⁴ ) ₂ [2]

Wherein, R ³ represents an alkyl group with 1-10 carbon atoms, R ⁴ represents an alkyl group with 1-10 carbon atoms or an acyl group with 1-10 carbon atoms (claim 4); the present invention also relates to the rights The manufacturing method of the transparent conductive film adhesion base described in claim 4 is characterized in that, the solvent that dissolves the indium compound represented by formula [1] and the tin compound represented by formula [2] is a β-diketone compound (claim 5) ; The present invention also relates to the manufacturing method of the transparent conductive film attachment base described in claim 4, characterized in that the amount of alkali metal contained is 2 mass ppm or less (claim 6).

Further, the present invention also relates to a method for manufacturing a substrate with a transparent conductive film, which is characterized in that a transparent conductive film is formed on a substrate with a curved surface or a concave-convex shape, directly or through an intermediate film, by a high-temperature sol treatment method (claim 7) . The present invention also relates to a method for manufacturing a substrate with a transparent conductive film, which is characterized in that, on a substrate with a curved surface or a concave-convex shape, a transparent conductive film is formed by a high-temperature sol treatment method through an intermediate film formed by a high-temperature sol treatment method (claims 8). The present invention also relates to a method for manufacturing a transparent conductive film-attached substrate, which is characterized in that, on a substrate with a curved surface or a concave-convex shape, directly or through an intermediate film, the transparent conductive film forming liquid described in claim 1 is used, and treated by high-temperature sol method to form a transparent conductive film (claim 9).

Description of drawings

FIG. 1 shows the results of ESCA measurement of the transparent conductive film-attached substrate of the present invention (the ITO film-attached glass substrate of Examples 1-3).

2 shows the results of measuring the indium content of the transparent conductive film-attached substrate (the ITO film-attached quartz fiber of Example 5) manufactured according to the method for manufacturing the transparent conductive film-attached substrate of the present invention by ESCA.

3 shows the results of the indium and tin content in the depth direction of the ITO film of the transparent conductive film-attached substrate (the ITO film-attached quartz fiber of Example 5) manufactured according to the transparent conductive film-attached substrate manufacturing method of the present invention by ESCA.

4 shows the results of measuring the indium content of the ITO film-attached quartz fiber (transparent conductive film-attached substrate) produced by the method for manufacturing the transparent conductive film-attached substrate of Comparative Example 2 by ESCA.

5 shows the results of measuring the indium and tin contents in the depth direction of the ITO film of the ITO film-attached quartz fiber (transparent conductive film-attached substrate) produced by the method for manufacturing the transparent conductive film-attached substrate of Comparative Example 2 by ESCA.

Detailed ways

Hereinafter, in the description of the present invention, the descriptions are the same for all the embodiments of the present invention except specific embodiments.

The first embodiment of the transparent conductive film forming liquid of the present invention is characterized by containing an indium compound represented by the following formula [1]:

In(R ¹ COCHCOR ² ) ₃ [1]

and a tin compound represented by the following formula [2]:

(R ³ ) ₂ Sn(OR ⁴ ) ₂ [2]

In the formula [1], R ¹ and R ² independently represent an alkyl group or a phenyl group having 1-10 carbon atoms (the same below). Specific examples: methyl, ethyl, n-propyl, n-butyl, tert-butyl, etc. Among them, indium triacetylacetonate (In(CH ₃ COCHCOCH ₃ ) ₃ ) is particularly preferable as the indium compound represented by the formula [1].

In formula [2], R ³ represents an alkyl group with 1-10 carbon atoms, and R ⁴ represents an alkyl group with 1-10 carbon atoms or an acyl group with 1-10 carbon atoms (the same below). Specifically, ^R3, for example, methyl, ethyl, n-propyl, n-butyl, tert-butyl, etc.; ^R4, for example, methyl, ethyl, n-propyl, n-butyl, tert-butyl, etc. group, acyl group such as acetyl group and propionyl group. Among them, di-n-butyltin diacetate ((n-Bu) ₂ Sn(OCOCH ₃ ) ₂ ) is particularly preferable as the tin compound represented by the formula [2].

When using a transparent conductive film-forming solution to form a transparent conductive film, it is generally believed that the closer the thermal decomposition temperatures of the indium compound and tin compound contained in the transparent conductive film-forming solution are, the more uniform the diffusion of the two can be, and a uniform film quality can be formed. In the transparent conductive film forming liquid of the present invention, the thermal decomposition temperature of the indium compound represented by the formula [1] and the tin compound represented by the formula [2] are close, specifically, the thermal decomposition temperature of indium triacetylacetonate is about 320°C , Di-n-butyl tin diacetate is around 360°C.

Therefore, when using the transparent conductive film forming liquid of the present invention to form a transparent conductive film, when the indium compound and the tin compound are decomposed by heat, and then deposited on the substrate or the intermediate film, it is generally considered that the indium compound and the tin compound are almost Thermal decomposition is carried out at the same time, and the two are uniformly diffused and accumulated (evaporation), forming a film with extremely uniform film quality, so that a transparent conductive film with extremely uniform conductivity and transparency can be formed. In addition, when the indium compound and the tin compound are decomposed by heat after the transparent conductive film forming liquid is applied, and then fixed on the substrate or the interlayer film, in the drying and/or firing after coating, it is generally considered that the indium compound and the tin compound The compound is thermally decomposed almost at the same time at a given temperature, and the two are uniformly diffused and fixed on the substrate or the intermediate film, which can form a film with extremely uniform film quality, thereby forming a transparent conductive film with extremely uniform conductivity and transparency. In this way, the film formed by the transparent conductive film forming liquid of the present invention has excellent conductivity and transparency, so it can be widely used in liquid crystal displays, electroluminescence displays, surface heaters, contact electrodes, solar cells, etc. field.

As long as the transparent conductive film-forming liquid of the present invention contains an indium compound and a tin compound, the contained ratio is not particularly limited, but preferably the In in the indium compound is more in mass than the Sn in the tin compound (the formed transparent conductive film is ITO film), more preferably according to the mass ratio, relative to 1 part of In in the indium compound, the content of Sn in the tin compound is 0.001-0.5, more preferably 0.05-0.35.

Containing an indium compound and a tin compound in the above mass ratio range can form a transparent conductive film excellent in transparency and resistance value uniformity, and the transparent conductive film having the above resistance value is particularly suitable for use as a transparent electrode for a touch panel, for example. .

The transparent conductive film-forming liquid according to the first embodiment of the present invention contains the indium compound represented by the formula [1], but it may be used in combination with other indium compounds. The indium compound used in combination is preferably a substance that forms indium oxide after thermal decomposition, for example, indium trichloride (InCl ₃ ), indium nitrate (In(NO ₃ ) ₃ ), indium triisopropoxide (In(OiPr) ₃ ) wait.

When used in combination with other indium compounds, the content of the indium compound represented by formula [1] in all indium compounds is preferably 80% by mass or more, more preferably 90% by mass or more, further preferably 95% by mass or more. It is preferable to contain more indium compounds represented by the formula [1].

The transparent conductive film forming liquid according to the first embodiment of the present invention contains the tin compound represented by the formula [2], but it may be used in combination with other tin compounds. The tin compound used in conjunction is preferably thermally decomposed to form tin oxide, for example, tin chloride, dimethyl tin dichloride, dibutyl tin dichloride, tetrabutyl tin, stannous octoate (Sn(OCOC ₇ H ₁₅ ) ₂ ), dibutyltin maleate, dibutyltin diacetylacetonate, etc.

When used in combination with other tin compounds, the content of the tin compound represented by formula [2] is preferably 80% by mass or more, more preferably 90% by mass or more, further preferably 95% by mass or more in all tin compounds. It is preferable to contain more tin compounds represented by formula [2].

In addition to the indium compound and the tin compound, the transparent conductive film forming liquid of the present invention preferably also contains the following monomers or compounds of these monomers as the third component: the second main group elements of the periodic table such as Mg, Ca, Sr, Ba, etc.; 3rd subgroup elements such as Sc, Y, etc.; lanthanide elements such as La, Ce, Nd, Sm, Gd, etc.; 4th subgroup elements such as Ti, Zr, Hf, etc.; 5th subgroup elements such as V, Nb, Ta, etc.; 6th subgroup elements such as Cr, Mo, W, etc.; 7th subgroup elements such as Mn, etc.; 9th subgroup elements such as Co, etc.; 10th subgroup elements such as Ni, Pd, Pt, etc.; 11th subgroup elements such as Cu, Ag, etc.; 12th subgroup elements such as Zn, Cd, etc.; 13th main group elements such as B, Al, Ga, etc.; 14th main group elements such as Si, Ge, Pb, etc.; Group elements such as P, As, Sb, etc.; the 16th main group elements Se, Te, etc.

Relative to indium, the addition ratio of the elements is preferably about 0.05-20 atomic %, and the addition ratio varies with the addition elements, and the elements and addition amounts that meet the required resistance value can be appropriately selected.

The organic solvent used in the transparent conductive film forming liquid of the present invention can be enumerated: ketone solvents such as acetone, methyl isobutyl ketone, and diethyl ketone; alcohols such as methanol, ethanol, propanol, isopropanol, and butanol; solvents; ethyl acetate, butyl acetate and other ester solvents; methyl cellosolve, tetrahydrofuran and other ether solvents; benzene, toluene, xylene and other aromatic hydrocarbons; hexane, heptane, octane, cyclohexane, etc. Aliphatic hydrocarbons, etc.

The type and amount of the above-mentioned organic solvent depends on the sheet resistance value of the transparent conductive film, etc., and can be appropriately determined according to the type of transparent conductive film, the thickness of the transparent conductive film, the type of organic solvent used, heating temperature, heating time, etc. . For example, under other conditions being the same, the sheet resistance value can be reduced by adding a large amount of an organic solvent that is easier to thermally decompose. As described above, a transparent conductive film having a desired sheet resistance value can be obtained by properly selecting and determining the type, addition amount and heating temperature of the organic solvent used.

The second embodiment of the transparent conductive film of the present invention is characterized by including an indium compound represented by the following formula [1]:

In(R ¹ COCHCOR ² ) ₃ [1]

and a tin compound represented by the following formula [2]:

(R ³ ) ₂ Sn(OR ⁴ ) ₂ [2]

It also includes a β-diketone compound that dissolves the indium compound represented by the formula [1] and the tin compound represented by the formula [2].

At this time, the β-diketone compounds include β-diketone compounds such as acetylacetone, etc.; β-ketoesters such as methyl acetoacetate, ethyl acetoacetate, etc.; Dimethyl malonate, diethyl malonate, etc., among which acetylacetone is preferred. The effects of the present invention can be exhibited more effectively by using acetylacetone.

In the transparent conductive film forming liquid in the second embodiment of the present invention, the indium compound represented by the formula [1] and the tin compound represented by the formula [2] are sufficiently dissolved, and the composition ratio in the transparent conductive film forming liquid does not Therefore, it is considered that a transparent conductive film with uniform film quality can be formed by using this transparent conductive film forming liquid to form a transparent conductive film.

The amount of the β-diketone compound in the transparent conductive film forming liquid in the second embodiment of the present invention is not particularly limited as long as it can dissolve the indium compound represented by the formula [1] and the tin compound represented by the formula [2]. However, it is preferred that the added amount of the β-diketone compound is as follows: according to the mass ratio, relative to 1 part of the β-diketone compound, the total metal component (In +Sn) content is 0.07 or less, more preferably in the range of 0.00001 to 0.07, still more preferably in the range of 0.001 to 0.04. By using the β-diketone compound in the above range, the indium compound represented by the formula [1] and the tin compound represented by the formula [2] can be dissolved at an appropriate concentration, thereby forming a more uniform transparent conductive film.

In addition, the transparent conductive film-forming liquid in the second embodiment of the present invention may be used in combination with the above-mentioned β-diketone compound and other solvents described in the above-mentioned first embodiment.

The type of solvent used in combination and the amount added depend on the set value of the sheet resistance of the transparent conductive film or the method of film formation, etc., in order to bring into play the effect of the present invention more effectively, the amount of β-diketone compound in all solvents The content is preferably 80% by mass or more, more preferably 90% by mass or more, further preferably 95% by mass or more, preferably more β-diketone compounds.

The transparent conductive film forming solution in the second embodiment of the present invention may use other indium compounds described in the above-mentioned first embodiment in combination, and similarly, other tin compounds described in the above-mentioned first embodiment may also be used in combination.

The transparent conductive film forming liquid in the third embodiment of the present invention is characterized by containing an indium compound and a tin compound, and an alkali metal content in the transparent conductive film forming liquid is 2 mass ppm or less.

A transparent conductive film formed with a transparent conductive film-forming solution having an alkali metal content of 2 mass ppm or less does not adversely affect light-emitting elements, especially in the field of liquid crystal displays, and can greatly improve the reliability of light-emitting elements.

In the transparent conductive film forming liquid in the third embodiment of the present invention, as described above, the content of the alkali metal must be 2 mass ppm or less, preferably 1.5 mass ppm or less, more preferably 1 mass ppm or less, further preferably 0.1 Mass ppm or below.

At this time, the alkali metals include lithium, sodium, potassium, rubidium, cesium, francium, etc. In consideration of the fact that they may be mixed into the transparent conductive film forming liquid, it is considered that the total amount of sodium and potassium should be adjusted.

The indium compound in the transparent conductive film forming liquid according to the third embodiment of the present invention is preferably a substance that becomes an indium oxide compound after thermal decomposition, for example, indium triacetylacetonate (In(CH ₃ COCHCOCH ₃ ) ₃ ), tribenzoyl Indium (In(C ₆ H ₅ COCHCOC ₆ H ₅ ) ₃ ), indium trichloride (InCl ₃ ), indium nitrate (In(NO ₃ ) ₃ ), indium triisopropoxide (In(Oi-Pr) ₃ )wait.

The tin compound in the transparent conductive film forming liquid of the third embodiment of the present invention is preferably a substance that becomes a ditin oxide compound after thermal decomposition, for example, tin chloride, dimethyl tin dichloride, dibutyl tin dichloride, Butyltin, stannous octoate (Sn(OCOC ₇ H ₁₅ ) ₂ ), dibutyltin maleate, dibutyltin diacetylacetonate, dibutyltin acetate, etc.

In addition, the transparent conductive film forming liquid according to the third embodiment of the present invention is not particularly limited as long as it contains an indium compound and a tin compound, but the indium compound is preferably an indium compound represented by the above formula [1]:

In(R ¹ COCHCOR ² ) ₃ [1]

The tin compound is a tin compound represented by the above formula [2]:

(R ³ ) ₂ Sn(OR ⁴ ) ₂ [2]

Among them, the indium compound represented by the formula [1] is particularly preferably indium triacetylacetonate (In(CH ₃ COCHCOCH ₃ ) ₃ ),

The tin compound represented by the formula [2] is particularly preferably di-n-butyltin diacetate ((n-Bu) ₂ Sn(OCOCH ₃ ) ₂ ).

Next, the method for producing the transparent conductive film-attached substrate of the present invention will be described.

The manufacturing method of the transparent conductive film attachment substrate of the present invention is a method of manufacturing a transparent conductive film attachment substrate directly or through an intermediate film on the substrate, and is characterized in that, on the substrate or the intermediate film, the first to the second The transparent conductive film-forming solution according to any one of the third embodiments forms a transparent conductive film by a chemical thermal decomposition method. That is, it is characterized in that the transparent conductive film is formed by a chemical thermal decomposition method using the above-mentioned transparent conductive film forming solution.

Here, the chemical thermal decomposition method refers to a method in which an indium compound and a tin compound contained in a transparent conductive film-forming liquid are deposited on a substrate or an intermediate film by thermal decomposition, and a method in which the transparent conductive film-forming liquid is coated , A method of immobilizing an indium compound and a tin compound contained in a transparent conductive film forming liquid on a substrate or an intermediate film by thermal decomposition. For example, spray method, immersion plating method, spin coating method (Spincoat method), LB method, sol-gel method, liquid phase epitaxy method, CVD method (chemical vapor deposition) such as thermal CVD method, plasma CVD method method, MOCVD method, pyrosol processing method (normal pressure CVD method by ultrasonic atomization), SPD method, Cat-CVD method, etc., among them, pyrosol processing method is particularly preferred. The high-temperature sol treatment method can produce a transparent conductive film with a more uniform film quality. In the high temperature sol treatment method, the transparent conductive film forming liquid has no chance of contacting the alkali metal after being sent to the conveying furnace (film forming device) until the transparent conductive film is formed, so it is extremely easy to form a transparent film with a low alkali metal content. conductive film.

According to the manufacturing method of the transparent conductive film attachment substrate of the present invention, by using the transparent conductive film forming liquid, the indium compound and the tin compound whose thermal decomposition temperature is very close can be uniformly diffused at a certain temperature to form a transparent conductive film with uniform film quality. In addition, by using the above-mentioned transparent conductive film forming liquid according to the second embodiment of the present invention, fully dissolving the indium compound represented by the formula [1] and the tin compound represented by the formula [2], the composition in the transparent conductive film forming liquid The ratio does not change, so a transparent conductive film with uniform film quality can be formed. In addition, by using the above-mentioned transparent conductive film-forming liquid according to the third embodiment of the present invention, it is possible to easily manufacture a transparent conductive film-attached substrate capable of greatly improving the reliability of light-emitting elements without adversely affecting light-emitting elements in the field of liquid crystal displays and the like. .

Specifically, when the indium compound and the tin compound contained in the transparent conductive film forming liquid are thermally decomposed and deposited on the substrate or the intermediate film, it is considered that the indium compound and the tin compound are thermally decomposed almost simultaneously at a certain temperature. Uniform diffusion and accumulation (evaporation) can form a film with extremely uniform film quality, thereby forming a transparent conductive film with extremely uniform conductivity and transparency. Also, when the indium compound and the tin compound are thermally decomposed and fixed on the substrate or the intermediate film after coating the transparent conductive film forming liquid, it is considered that the transparent conductive film forming liquid with a uniform composition is used for coating, and then after coating In drying and/or calcination, the indium compound and the tin compound, which have a thermal decomposition temperature close to each other, are thermally decomposed almost simultaneously at a certain temperature, and the two are uniformly diffused and fixed on the substrate or the intermediate film to form a film with extremely uniform film quality. Thus, a transparent conductive film with extremely uniform conductivity and transparency is formed.

In addition, the transparent conductive film manufactured according to the method for manufacturing a transparent conductive film attached substrate of the present invention has excellent conductivity and transparency, so it can be widely used in liquid crystal displays, electroluminescent displays, surface heaters, contact electrodes, solar cells, etc. Furthermore, in the method for producing the substrate to which the transparent conductive film is attached according to the present invention, a homogeneous film can be easily formed by using the chemical thermal decomposition method which is a general method for film formation.

The intermediate film may be a single-layer film or a film of two or more layers. The intermediate film includes, for example, a silicon oxide film, a polysilane film formed of an organopolysilane compound, a MgF ₂ film, a CaF ₂ film, a composite oxide film of SiO ₂ and TiO ₂ , and the like. These intermediate films are formed, for example, to prevent diffusion of Na ions when soda glass is used as a substrate. In addition, it is also possible to prevent reflection or improve transparency by forming a base film having a different refractive index from the transparent conductive film, preferably a lower refractive index. The film can be formed by known film-forming methods such as sputtering, CVD, spraying, dipping, etc. The thickness of the film is not particularly limited, but is usually about 20-200 nm.

The matrix can be in sheet form (substrate), honeycomb form, fiber form, spherical form, foam form or their composites, etc., as long as the components of the transparent conductive film forming liquid have heat resistance at the temperature of thermal decomposition, they are not affected. Any restrictions, such as glass substrate, ceramic substrate, metal substrate, etc. Among them, a glass substrate is preferably used in the method for producing the transparent conductive film-attached base of the present invention. The glass substrate includes, for example, silicate glass (quartz glass), alkali silicate glass, soda lime glass, potassium lime glass, lead glass, barium glass, borosilicate glass, and the like.

The film thickness of the transparent conductive film formed in the transparent conductive film-adhered substrate manufacturing method of the present invention is not particularly limited, and can be appropriately selected according to its use, etc., but when forming an ITO film with a sheet resistance value of 30Ω/□ or less, Generally 50nm or above, when forming an ITO film with a sheet resistance of 60-200Ω/□, generally 30nm or above, when forming an ITO film with a sheet resistance of 200-3000Ω/□, generally 10- 25nm.

In the manufacturing method of the transparent conductive film attachment substrate of the present invention, when the high-temperature sol treatment method is adopted, the transparent conductive film-forming liquid in which the indium compound and the tin compound are dissolved in the organic solvent is sprayed into a relatively regular granular The aerosol formed by the small droplets of the indium compound and the tin compound is sent to the substrate in the heating furnace, and the temperature of the heating furnace is controlled at a uniform temperature where the indium compound and the tin compound are thermally decomposed to form indium oxide and tin oxide, for example 300-800°C, vaporize the indium compound and the tin compound into a gaseous state in a heating furnace, and then react on the substrate to form a transparent conductive film.

When using a substrate having a curved surface or a concavo-convex shape, it is preferable to form a transparent conductive film by high temperature sol treatment directly or through an intermediate film. A transparent conductive film with an extremely uniform film thickness can be easily formed on a substrate having a curved surface or a concave-convex shape by using a high-temperature sol treatment method. That is, it is generally difficult to form a film with a uniform thickness on a substrate with a curved surface or uneven shape. However, if the high-temperature sol treatment method is used, the metal compound that becomes a gaseous state by heating and sublimating is also uniform on the curved surface or uneven parts. Contact and thermal decomposition can produce a transparent conductive film attachment substrate having a transparent conductive film with an extremely uniform overall film thickness.

In addition, when a film is formed on a flat plate by pyrosol treatment, the metal compound sublimated by heating may sneak into the inner side of the flat plate (outer peripheral part of the inner surface), thereby causing poor conductivity of touch panels and the like. For this reason, it is necessary to control to prevent sneaking into the inner side of the flat plate, but as far as the curved surface or the concave-convex shape substrate (such as the fibrous matrix or the spherical matrix) is concerned, it is better to use it to sneak into the inside of the flat plate and to be on the curved surface or concave-convex shape. On the outside, depending on the situation (such as the case of a hemispherical substrate such as a bowl), a transparent conductive film with uniform film thickness can also be formed on the inner surface.

The substrate that can form a transparent conductive film by high-temperature sol treatment method is not particularly limited if it is a substrate with a curved surface or a concave-convex shape, even if it is a sheet-shaped substrate (substrate), a honeycomb substrate, or a fibrous substrate with a curved surface or a concave-convex shape. , spherical substrates, foam substrates, etc. are also possible, but fibrous or spherical substrates are preferred. In addition, the substrate having the curved surface is preferably a curved substrate with a radius of curvature of about 1-1000 mm.

Here, the fibrous matrix refers to a fibrous matrix with a diameter of about 0.01-15mm, and the spherical matrix refers to a spherical surface including an ellipsoidal matrix, a partially missing spherical matrix (such as a hemisphere), and a light bulb-shaped matrix. The substrate is 30% or more, preferably 50% or more, more preferably 80% or more of the entire substrate surface (film-forming portion).

The substrate for attaching the fibrous transparent conductive film is particularly suitable for optical communication cables, and is particularly preferably quartz fibers. The spherical transparent conductive film attachment base is especially suitable for lighting electrodes.

In addition, according to the present invention, the transparent conductive film that can be formed on a substrate with a curved surface or a concave-convex shape by high-temperature sol treatment is not limited to an indium oxide film (ITO film) doped with tin, but also a tin oxide film doped with fluorine. (FTO film), antimony-doped tin oxide film (ATO film), indium-doped zinc oxide film, aluminum-doped zinc oxide film, etc.

Example

Below, the present invention is further described through examples, but the example of this description does not limit the technical scope of the present invention.

Example 1

Dissolve indium triacetylacetonate (In(AcAc) ₃ ) in acetylacetone so that the molar concentration is 0.2 mol/L to obtain a yellow transparent solution. Di-n-butyltin diacetate was added as a tin compound to this solution so that Sn/In=5% by mass, thereby preparing an ITO film-forming liquid (transparent conductive film-forming liquid). At this time, the content of the alkali metal was as follows: indium triacetylacetonate was 0.03 mass ppm, acetylacetone was 0.05 mass ppm, and di-n-butyltin diacetate was 0.03 mass ppm.

Use this ITO film forming liquid to pass through the high-temperature sol treatment method, adjust the chemical thermal decomposition amount that the atomization of ITO film forming liquid produces, meanwhile, form a film thickness on the glass substrate (SLG substrate) with _SiO2 film coating bottom by dipping method: 20nm ITO film, obtain the ITO film attached glass substrate (transparent conductive film attached substrate) with colorless and transparent ITO film.

Example 2

An ITO film with a film thickness of 40 nm was formed on a glass substrate in the same manner as in Example 1 above to obtain an ITO film-attached glass substrate with a transparent ITO film.

Example 3

An ITO film with a film thickness of 200 nm was formed on a glass substrate in the same manner as in Example 1 above to obtain an ITO film-attached glass substrate with a transparent ITO film.

Comparative example 1

Dissolve indium triacetylacetonate in acetylacetone so that the molar concentration is 0.2mol/L to obtain a yellow transparent solution. Tri-n-octyl tin oxide (Tri-n-Octyl tin oxide) was added as a tin compound to this solution so that Sn/In=5% by mass, thereby preparing an ITO film-forming liquid.

Adopt this ITO film forming liquid to pass through high-temperature sol treatment method, adjust the chemical thermal decomposition amount that ITO film forming liquid atomization produces, simultaneously, form film thickness on the glass substrate (SLG substrate) with _SiO2 film coating bottom by immersion method 30nm ITO film, an ITO film-attached glass substrate with a slightly yellowish transparent ITO film was manufactured.

Example 4

Dissolve indium triacetylacetonate in acetylacetone so that the molar concentration is 0.2mol/L to obtain a yellow transparent solution. Di-n-butyltin diacetate having an alkali metal content of 0.03 mass ppm was added to the solution to make it Sn/In=5 mass%, and then sodium stearate was added to make it Na/In=10 mass ppm , thereby preparing an ITO film-forming solution.

Adopt this ITO film forming liquid to pass through high-temperature sol treatment method, adjust the chemical thermal decomposition amount that ITO film forming liquid atomization produces, simultaneously, form film thickness on the glass substrate (SLG substrate) with _SiO2 film coating bottom by immersion method 40nm ITO film, manufactured ITO film attached to glass substrate.

evaluate

The specific resistance values of the ITO film-attached glass substrates in the aforementioned Examples 1-4 and Comparative Example 1 were measured using Loresta (Mitsubishi Chemical Corporation), and the sheet resistance values were obtained. In addition, the sheet resistance value was calculated|required by ratio resistance value/film thickness of a conductive film. In the ITO film-attached glass substrates of Examples 1-4 and Comparative Example 1, optional parts a-c (3 places) were measured with a magnetic spectrophotometer (Hitachi, Ltd.) for light transmittance at a wavelength of 550 nm. In addition, the indium content and tin content in the ITO film depth direction in the ITO film-attached glass substrates of Examples 1-3 and Comparative Example 1 were measured by ESCA. The ITO film attached to the ITO film in the glass substrate of Examples 1-4 was dissolved by acid corrosion, and the content of the alkali metal was measured with an ICP emission spectrochemical analysis device.

Table 1 shows the measurement results of the sheet resistance value, Table 2 shows the measurement results of the light transmittance, and Table 3 shows the measurement results of the alkali metal content. In addition, FIG. 1 shows the result of the ITO film adhesion glass substrate of Example 1-3 measured by ESCA.

Table 1 Thickness of ITO film (nm) Sheet resistance value of ITO film (Ω/□) Example 1 20 500 Example 2 40 100 Example 3 200 10 Example 4 40 100 Comparative example 1 30 10000

Table 2 Light transmittance a(%) of ITO film Light transmittance b(%) of ITO film Light transmittance c(%) of ITO film Example 1 90 90 91 Example 2 88 89 89 Example 3 80 81 80 Example 4 88 88 89 Comparative example 1 88 86 90

table 3 Alkali metal content (mass ppm) Example 1 0.1 Example 2 0.1 Example 3 0.1 Example 4 12

(result)

As can be seen from Table 1, according to the manufacture method of the transparent conductive film attachment substrate of the present invention, the ITO film attachment substrate with a sheet resistance value of 10-500 Ω/□ can be produced by changing the thickness of the film, and the ITO film attachment substrate applicable to various purposes can be obtained. The ITO film of the desired sheet resistance value of the ITO film is attached to the substrate.

It can be seen from Table 2 that the light transmittances of the ITO film-attached glass substrates of Examples 1-4 of the present invention are almost equal in any part, indicating that the transparency of the film is uniform.

As can be seen from Table 3, in the ITO film in the ITO film glass substrate of the embodiment of the present invention 1-3, alkali metal content is 0.1 mass ppm, can manufacture the higher reliability by making light-emitting elements such as liquid crystal display with this ITO film light emitting element. On the other hand, in the ITO film in the ITO film glass substrate of embodiment 4, alkali metal content is 12 mass ppm, when making light-emitting element such as liquid crystal display with this ITO film, then light-emitting element reliability is very low, and its application is restricted. limit.

It can be seen from FIG. 1 that in the ITO film-attached glass substrates of Examples 1-3 of the present invention, the content of tin is almost constant, and a film in which indium and tin are uniformly dispersed on the surface of the film and inside the film is formed. On the other hand, in the ITO film-attached glass substrate of Comparative Example 1, tin was not detected by ESCA, but tin was only thermally decomposed, and no film was formed together with indium.

Example 5

Using the ITO film-forming solution of Example 1, the amount of chemical thermal decomposition due to the atomization of the ITO film-forming solution is adjusted by high-temperature sol treatment, and at the same time, an ITO film is formed on a quartz fiber with a diameter of 500 μm to obtain an ITO film. Attached quartz fiber (transparent conductive film attachment substrate).

Comparative example 2

Using an ITO target (タ一ゲット) (a sintered product of In ₂ O ₃ and SnO ₂ ) of Sn/In=10% by mass, under the condition of an oxygen partial pressure of 0.7 Pa, a diameter of 500 μm The quartz fiber was rotated 20 times for 1 min to form ITO, and the ITO film was attached to the quartz fiber.

(evaluate)

The above-mentioned ITO film-attached quartz fiber of Example 5 and Comparative Example 2 was cut into a length of about 1 cm at any position, and the indium content was measured by ESCA at four different surface positions and the thickness of the ITO film was detected. The content (content ratio) of indium and tin was measured in the depth direction of the ITO film by the same method.

Fig. 2 shows the measurement results of the indium content in the ITO film-attached quartz fiber of Example 5, and Fig. 3 shows the measurement results of the indium and tin contents in the depth direction of the ITO film. Fig. 4 shows the measurement results of the indium content in the ITO film-attached quartz fiber of Comparative Example 2, and Fig. 5 shows the measurement results of the indium and tin contents in the depth direction of the ITO film.

(result)

It can be seen from FIG. 2 that in the ITO film-adhered quartz fiber of Example 5, the film thickness of the ITO film is in the range of 95-105 nm, and an ITO film with an extremely uniform film thickness can be formed. In addition, it can be seen from FIG. 3 that in the ITO film-attached quartz fiber of Example 5, the content of tin is almost constant, and a film in which indium and tin are uniformly dispersed on the surface and inside of the film is formed.

On the contrary, in the ITO film-attached quartz fiber of Comparative Example 2, it can be seen from FIG. 4 that the thickness of the ITO film is in the range of about 70-100 nm, and the deviation is large, and the formed ITO film is an ITO film with non-uniform film thickness. In addition, as can be seen from FIG. 5 , in the ITO film-attached quartz fiber of Comparative Example 2, the tin distribution in the film is uneven because the tin content is high on the film surface.

Invention effect

The transparent conductive film-forming solution of the present invention can form a transparent conductive film that is extremely uniform in terms of sheet resistance, transparency, and distribution of indium compounds and tin compounds in the depth direction of the transparent conductive film. With the transparent conductive film-forming liquid of the present invention, it is also possible to form a transparent conductive film capable of improving the reliability of a light-emitting element.

According to the method for producing a transparent conductive film-attached base of the present invention, a transparent conductive film-attached base that is extremely uniform in sheet resistance, transparency, and distribution of indium compounds and tin compounds in the depth direction of the transparent conductive film can be produced. According to the manufacturing method of the transparent conductive film attachment substrate of the present invention, it is easy to manufacture the transparent conductive film that can improve the reliability of the light-emitting element.

According to the manufacturing method of the transparent conductive film attachment substrate of the present invention, a transparent conductive film with an extremely uniform film thickness can be formed on a substrate having a curved surface or unevenness, and the transparent conductive film attachment substrate with an extremely uniform film thickness can be easily manufactured.

Claims (9)

1. The liquid for forming a transparent conductive film is characterized in that: it comprises an indium compound represented by the following formula [1] and a tin compound represented by the following formula [2]: In(R ¹ COCHCOR ² ) ₃ [1] Wherein, R ¹ and R ² independently represent an alkyl or phenyl group with 1-10 carbon atoms; (R ³ ) ₂ Sn(OR ⁴ ) ₂ [2] Wherein, R ³ represents an alkyl group with 1-10 carbon atoms, and R ⁴ represents an alkyl group with 1-10 carbon atoms or an acyl group with 1-10 carbon atoms. 2. The transparent conductive film forming solution according to claim 1, wherein the solvent for dissolving the indium compound represented by the formula [1] and the tin compound represented by the formula [2] is a β-diketone compound. 3. The transparent conductive film-forming solution according to claim 1 or 2, wherein the amount of the alkali metal contained is 2 mass ppm or less. 4. The manufacture method of transparent conductive film attachment substrate, this method is the method for making transparent conductive film attachment substrate directly or through intermediate film to form transparent conductive film on substrate, it is characterized in that: on described substrate or intermediate film, with comprising The transparent conductive film forming liquid of the indium compound represented by the following formula [1] and the tin compound represented by the following formula [2] forms a transparent conductive film by chemical thermal decomposition method: In(R ¹ COCHCOR ² ) ₃ [1] Wherein, R ¹ and R ² independently represent an alkyl or phenyl group with 1-10 carbon atoms; (R ³ ) ₂ Sn(OR ⁴ ) ₂ [2] Wherein, R ³ represents an alkyl group with 1-10 carbon atoms, and R ⁴ represents an alkyl group with 1-10 carbon atoms or an acyl group with 1-10 carbon atoms. 5. The manufacturing method of the substrate for attaching a transparent conductive film according to claim 4, characterized in that the solvent for dissolving the indium compound represented by the formula [1] and the tin compound represented by the formula [2] is a β-diketone compound. 6. The method for producing a substrate for attaching a transparent conductive film according to claim 4 or 5, characterized in that the amount of the alkali metal contained is 2 mass ppm or less. 7. The manufacturing method of the transparent conductive film attached to the substrate, characterized in that: on the substrate with a curved surface or a concave-convex shape, directly or through an intermediate film, a transparent conductive film is formed by a high-temperature sol treatment method. 8. The manufacturing method of transparent conductive film attached substrate, it is characterized in that: on the substrate with curved surface or concave-convex shape, through the intermediate film formed by high temperature sol treatment method, form transparent conductive film with high temperature sol treatment method. 9. The manufacture method of transparent conductive film attached substrate is characterized in that: on the substrate with curved surface or concave-convex shape, directly or through intermediate film, form transparent conductive film forming liquid by high-temperature sol treatment method with claim 1 conductive film.

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