JP2006128098A - Coating liquid for forming transparent conductive film, transparent conductive film, and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating liquid for forming a transparent conductive film capable of the pattern formation (trimming) and laser baking of the transparent conductive film by applying laser beams. <P>SOLUTION: The coating liquid for forming the transparent conductive film is obtained by dissolving an organic coloring matter to solution comprising acetylacetoneindium, an organic metal compound for dopant, a cellulose derivative, alkylphenol and/or alkenylphenol, and dibasic acid ester and/or benzyl acetate. After a substrate is coated with the coating liquid before drying, trimming is made by applying laser beams as needed, baking is made at a temperature of 400°C or higher, or laser baking is made, thus forming the transparent conductive film pattern. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a coating liquid for forming a transparent conductive film and a transparent conductive film. More specifically, a coating liquid capable of forming a fine transparent conductive film pattern having both transparency and conductivity on a heat-resistant substrate such as glass or ceramics, and a transparent conductive film formed using the coating liquid About.

  As a transparent conductive film used for functional coatings such as liquid crystal displays, electroluminescence, plasma display, etc., transparent electrodes, touch panels, solar batteries, transparent electrodes, heat ray reflection, electromagnetic shielding, antistatic, antifogging, etc. Indium oxide-based transparent conductive materials represented by tin-doped indium oxide (hereinafter sometimes referred to as “ITO”) are known.

  Here, physical methods such as a vacuum deposition method, a sputtering method, and a chemical vapor deposition method are widely used as a method for producing the ITO transparent conductive film. These methods can form a uniform ITO transparent conductive film excellent in transparency and conductivity on a substrate. However, the film forming apparatus used for this is very expensive because it is based on a vacuum vessel, and the component gas pressure in the manufacturing apparatus must be precisely controlled every time the substrate is formed. There is a problem with sex.

  As a manufacturing method for solving the above-mentioned problem, a method of applying on a substrate using a coating solution for forming a transparent conductive film in which an indium compound and a tin compound are dissolved in a solvent (hereinafter sometimes referred to as “coating method”). ) Is being considered. In this method, the ITO transparent conductive film is formed by a simple manufacturing process of coating, drying, and baking.

In the coating method, various coating solutions have been developed as coating solutions containing an indium compound and a tin compound. For example, Patent Document 1 discloses a mixed solution of indium nitrate containing halogen ions or carboxyl groups and tin alkyl nitrate. However, Patent Document 2 discloses a mixture of an organic indium compound containing an alkoxyl group and an organic tin compound, Patent Document 3 includes a mixture of indium nitrate and an organic tin compound, and Patent Document 4 includes indium nitrate and nitric acid. A mixture of inorganic compounds such as tin is disclosed in Patent Document 5 from a mixture of organic indium nitrate such as indium dicarboxylate and alkyl tin nitrate, and Patent Document 6 includes an organic indium complex coordinated with acetylacetone and a tin complex. The organic compound mixed solution similar to the above is disclosed in Patent Document 7 and the same organic compound is also disclosed in Patent Document 8. Object mixture is disclosed, respectively.
As can be seen from these patent documents, most of the conventional coating solutions use indium or tin nitrates, organic or inorganic compounds made of halides, or organometallic compounds such as metal alkoxides. However, a coating solution using nitrate or halide has a problem that corrosive gases such as nitrogen oxides and chlorine are generated during firing, resulting in equipment corrosion and environmental pollution. Moreover, in the coating liquid using a metal alkoxide, since a raw material is easy to hydrolyze, there exists a problem in stability of a coating liquid. In addition, many of the coating solutions using the organometallic compound have a problem that wettability with respect to the substrate is poor and a non-uniform film is easily formed.

  Patent Document 9 discloses a transparent conductive film-forming solution containing acetylacetone indium, acetylacetone tin, hydroxypropylcellulose, alkylphenol and / or alkenylphenol, dibasic acid ester and / or benzyl acetate as a coating solution that improves these problems. A coating solution is disclosed. This coating solution improves the wettability of the coating solution to the substrate by containing hydroxypropyl cellulose in a mixed solution of acetylacetone indium and acetylacetone tin, and at the same time, the viscosity of the coating solution is controlled by the content of hydroxypropylcellulose as a viscosity agent. It is possible to use various coating methods such as spin coating, spray coating, wire bar coating, dip coating, and screen printing.

  Furthermore, as an improved coating solution for spin coating, spray coating, and dip coating, Patent Document 10 discloses an organic indium compound (acetylacetone indium, indium octylate), organic tin (acetylacetone tin, tin octylate), and an organic solvent. And a transparent conductive film forming coating solution using a solution obtained by diluting an acetylacetone solution in which an alkylphenol and / or alkenylphenol is dissolved with an alcohol. .

  If the above-described improved coating solution is used, the coating solution is applied by pattern printing such as screen printing, or an arbitrary transparent conductive film pattern is produced by wet etching the formed transparent conductive film. Can do. The former is a method of forming an arbitrary pattern at the application stage, and a transparent conductive film pattern can be easily produced at low cost, but there is a problem that it is difficult to produce a fine pattern. On the other hand, the latter is a method of forming an arbitrary pattern after forming a transparent conductive film, and a fine transparent conductive film pattern can be produced, but it requires complicated steps such as resist coating, etching, and resist removal. There is a problem in manufacturing cost.

Therefore, a method of irradiating a powerful laser used in microfabrication of an electrode such as a multilayer ceramic capacitor to eliminate the coating film of the irradiated portion and forming a fine pattern is considered. This method could not be applied to the film having a transparent conductive film forming coating solution applied and dried, or the transparent conductive film itself, because there was no absorption in a general laser wavelength region of 300 to 1200 nm.
Moreover, in the method of obtaining an ITO transparent conductive film using the above coating liquid, if laser irradiation is used for baking after coating and drying, it becomes possible to perform baking more easily, and further laser irradiation if pattern irradiation is performed. Since only the irradiated portion can be converted into a transparent conductive film, fine patterning is also possible, but for the same reason as above, it could not be applied.
Japanese Patent Publication No.57-138108 Japanese Patent Publication No. 61-26679 JP-A-4-255768 JP 57-36714 A Japanese Patent Laid-Open No. 57-212268 Japanese Patent Publication No. 63-25448 Japanese Patent Publication No. 2-20706 Japanese Patent Publication No.63-19046 JP-A-6-203658 JP-A-6-325637

    An object of the present invention is to form a transparent conductive film, such as ITO, which can form a fine pattern and has both transparency and conductivity, and a method for producing the same, and to form the transparent conductive film at low cost and easily. It is to provide a coating solution.

    The inventors have applied a laser beam to a coating solution for forming a transparent conductive film in which acetylacetone indium, an organometallic compound for dopant, and hydroxypropyl cellulose are dissolved in alkylphenol and / or alkenylphenol, dibasic acid ester and / or benzyl acetate. By containing an organic dye that absorbs the light, the coating film can be patterned (trimming) or laser baked by a laser beam, and the transparent conductive film obtained by applying, drying and baking the coating liquid is transparent. And the present inventors have found that the conductivity is good and have reached the present invention.

    That is, the coating liquid for forming a transparent conductive film according to the present invention for achieving the above-described object comprises indium acetylacetone, an organometallic compound for a dopant, a cellulose derivative, an organic dye, an alkylphenol and / or alkenylphenol, a dibasic acid ester, and A coating liquid for forming a transparent conductive film containing benzyl acetate, wherein the total content of indium acetylacetone and the organometallic compound for the dopant is 1 to 30% by weight, and the content of the cellulose derivative is 0.1 to 5% by weight %, And the organic dye content is 0.05 to 2% by weight.

    Another transparent conductive film forming coating liquid according to the present invention is characterized in that, in the transparent conductive film forming coating liquid according to the present invention, the organic dye has absorption in a wavelength region of 300 to 1200 nm. The total content of the acetylacetone indium and the organometallic compound for dopant is 5 to 20% by weight, and the content ratio of the acetylacetone indium and the organometallic compound for dopant is a weight ratio of acetylacetone indium / the organometallic compound for dopant. = 99/1 to 80/20, characterized in that the organometallic compound for dopant is an organotin compound, and further, the organotin compound is acetylacetone tin, The cellulose derivative is characterized by being hydroxypropylcellulose

    A method for producing a transparent conductive film for achieving the object of the present invention is characterized in that a transparent conductive film forming coating solution having the above composition is applied onto a substrate, dried, and then fired at a temperature of 400 ° C. or higher. It is what. In this case, the application of the coating solution onto the substrate is also performed by a screen printing method or a wire bar coating method. Another method for producing a transparent conductive film according to the present invention is characterized in that a transparent conductive film-forming coating solution having the composition described above is applied onto a substrate, dried, and then laser-fired.

    The transparent conductive film for achieving the object of the present invention is obtained by the transparent conductive film-forming coating liquid having the composition described above and the method for producing the transparent conductive film described above. .

    Since the coating liquid for forming a conductive film according to the present invention contains an organic dye that absorbs a laser beam, the coating film (coated / dried film) is patterned (trimmed) or laser baked (patterned) by laser beam irradiation. Including laser firing). In addition, the transparent conductive film obtained by applying, drying, and baking (heating or laser irradiation) this coating solution has good transparency and conductivity, and in displays, touch panels, solar cells, etc., transparency and conductivity. This is industrially useful because it can be applied to a transparent electrode that requires a fine transparent conductive film pattern.

Hereinafter, embodiments of the present invention will be described in detail.
The coating liquid for forming a transparent conductive film of the present invention is a case where acetylacetone indium (hereinafter sometimes referred to as “AcAcIn”) is used as the indium compound, and acetylacetone tin (hereinafter referred to as “AcAcSn”) is used as the organometallic compound for the dopant. An organic dye having absorption in a predetermined wavelength region is added to a coating solution containing a cellulose derivative as a binder and alkylphenol and / or alkenylphenol and a dibasic acid ester and / or benzyl acetate as a solvent. .
Therefore, the dry film obtained by applying and drying the transparent conductive film-forming coating solution on a substrate such as glass also has absorption in the same wavelength region as the added organic dye.
As the dopant organometallic compound, for example, an organotin compound, an organozinc compound, an organotungsten compound, an organotitanium compound, an organozirconia compound, and the like can be applied. However, the indium oxide is finally doped as an oxide. However, the present invention is not limited to this as long as it can function as a transparent conductive material. Among these, an organic tin compound is preferable because it can form ITO having excellent transparency and conductivity. Examples of the organic tin compound include, but are not limited to, acetylacetone tin, tin octylate, tin oxalate, tin formate and the like, as long as tin can be effectively doped.

  When this dry film is irradiated with a powerful laser beam having a wavelength in the same wavelength range as the added organic dye, the laser beam is absorbed and an instantaneous temperature rise occurs, and the irradiated portion disappears. That is, after the coating liquid for forming a transparent conductive film is coated on a substrate and dried, the coating film can be trimmed by irradiating unnecessary portions with a powerful laser beam. Moreover, it can also use for baking of the said dry film by adjusting laser irradiation intensity | strength moderately. In this case, if pattern irradiation is performed, only the laser irradiation portion can be converted into a transparent conductive film, so that fine patterning is also possible.

The wavelength region band of the organic dye is preferably an organic dye having absorption in a wavelength region of 300 to 1200 nm.
When the wavelength is less than 300 nm, the glass substrate absorbs the laser beam and is easily broken by thermal shock, which is not preferable.
Also, in the region exceeding the wavelength of 1200 nm, an industrially suitable laser (low price, high output) having an output wavelength is not found in that region, and if the wavelength is too long, an optical fiber cannot be used.
More specifically, a wavelength of 500 nm, which is an output wavelength region of various lasers such as a solid-state laser such as a YAG laser (wavelength: 1064 nm, 532 nm [second harmonic]), a semiconductor laser such as a GaAlAs system (wavelength: 810 nm), or the like. An organic dye having absorption in a wavelength region near 800 nm or 1000 nm is preferable.
In addition, the above organic dye must burn and disappear in the process of forming a transparent conductive film in the baking process after coating and drying, and various organic dyes can be considered. There is no particular limitation.
Examples of the organic dye include VALIFAST RED3304 (maximum absorption wavelength 530 nm), VLIFAST RED 3306 (maximum absorption wavelength 500 nm), VALIFAST RED 3320 (maximum absorption wavelength 515 nm), VALIFAST BROWN 2402 (maximum absorption wavelength 430 nm) manufactured by Orient Chemical, NUBIAN BLACK PC-0850 (maximum absorption wavelength 575 nm), VALIFAST BLUE 2620 (maximum absorption wavelength 670 nm), etc., PRO-JET 800NP (maximum absorption wavelength 775 nm), PRO-JET 825LDI (maximum absorption wavelength 780 nm), PRO-JET JET 830NP (maximum absorption wavelength 810 nm), PRO-JET 950NP (maximum absorption wavelength 940 nm), etc., Yamamoto Kasei YKR-2200 (maximum absorption wavelength 985 nm), YKR-3080 (maximum absorption wavelength 1015 nm), Ciba Specialty Chemicals An organic dye such as ORASOL BLUE-GN (maximum absorption wavelength: 670 nm) manufactured by the company can be used.

  The organic dye is necessary for patterning (trimming) and laser firing (including pattern laser firing) of the dried film by laser irradiation, and is preferably 0.05 to 2% by weight. When the content is less than 0.05% by weight, it becomes difficult to absorb the laser beam, and the trimming property and the firing effect (temperature rise of the dry film during laser irradiation) are impaired. On the other hand, when the content is more than 2% by weight, the dye is burnt and lost in the baking step to form a porous ITO film, so that the film strength and conductivity are impaired.

  Organometallic compounds for dopants such as AcAcIn and AcAcSn are main compound raw materials for forming a transparent conductive film on a substrate, and the total content is preferably in the range of 1 to 30% by weight, more preferably Is preferably 5 to 20% by weight. If the content is less than 1% by weight, the film thickness of the ITO film becomes thin and sufficient conductivity cannot be obtained. If the content is more than 30% by weight, the film is cracked and the conductivity is impaired. The content ratio of AcAcIn and the organometallic compound for dopant is preferably about AcAcIn / organometallic compound for dopant = 99/1 to 80/20, more preferably 95/5 to 85/15. If the ratio is out of the range, the carrier density or the carrier mobility is decreased, and the conductivity is rapidly deteriorated.

As the binder, any material may be used as long as the wettability with respect to the substrate is improved and the viscosity of the coating solution can be adjusted, and the material burns at a firing temperature or lower. A cellulose derivative is effective as such a material, and examples thereof include methyl cellulose, ethyl cellulose, hydroxypropyl cellulose (hereinafter sometimes referred to as “HPC”), and among them, HPC is preferable. When HPC is used, sufficient wettability (restraint) is obtained at a content of 0.1 to 5% by weight, and at the same time, a wide range of viscosity adjustment from low viscosity to high viscosity can be performed. Also, the combustion start temperature of HPC is about 300 ° C. Therefore, if the substrate after coating and drying is baked at a temperature of 400 ° C. or higher, HPC is thermally decomposed, so that it does not hinder the grain growth of the generated ITO particles, A film having good conductivity can be formed.
Here, when the HPC content is less than 0.1% by weight, the wettability with respect to the substrate deteriorates, and the coating liquid repels in the drying process after coating, forming a non-uniform film, or film when fired. The film formability is impaired, for example, cracks occur. On the other hand, if the HPC content is more than 5% by weight, gel-like HPC is likely to remain in the coating solution and at the same time densification of the film is suppressed. Is damaged.
In addition, for example, when ethyl cellulose is used as the cellulose derivative instead of HPC, the viscosity of the coating solution is approximately 1/100 when HPC is used, and the printability such as pattern printability and film thickness uniformity is slightly inferior. .

  As the solvent, a mixed solution of an organometallic compound for dopants such as AcAcIn and AcAcSn, an alkylphenol and / or alkenylphenol that dissolves cellulose derivatives well, and a dibasic acid ester and / or benzyl acetate is used. Examples of the alkylphenol and alkenylphenol include cresols, para-tert-butylphenol, octylphenol, nonylphenol, cashew nut shell liquid [3-pentadedecydeal phenol] and the like. Examples of the dibasic acid ester include succinic acid ester, glutaric acid ester, and adipic acid ester.

  The coating liquid for forming a transparent conductive film of the present invention can be prepared by heating and dissolving the indium compound, the organometallic compound for dopant, the binder, and the organic dye in a solvent. Heating dissolution is performed by stirring at 0.5 to 12 hours at a heating temperature of 60 to 200 ° C. When the heating temperature is lower than 60 ° C, dissolution does not proceed, and acetylacetone indium and acetylacetone tin as an organic metal compound for dopant are liable to be precipitated and the characteristics are deteriorated. When the heating temperature is higher than 200 ° C, evaporation of the solvent becomes remarkable. And the coating liquid composition changes, which is not preferable. As for organic dyes, those having good solubility may be added to the cooled solution after dissolution by heating and dissolved by stirring.

  The transparent conductive film of the present invention is produced by applying the transparent conductive film-forming coating solution onto a substrate, drying, patterning (laser trimming) as necessary, and then heating and baking. Pattern laser firing by laser irradiation is also possible.

As the coating method, the viscosity of the coating liquid can be adjusted to several mPa · s to several hundred thousand mPa · s depending on the type and content of the cellulose derivative and the type of solvent, so that spin coating, spray coating, wire Various coating methods such as bar coating, dip coating, screen printing, and ink jet printing can be applied.
For example, when a high-viscosity type HPC and phenols are combined, a high-viscosity coating solution of about 120 k to 300 kmPa · s suitable for wire bar coating and screen printing can be obtained. In addition, it is possible to further dilute a coating solution using a low-viscosity type HPC with a solvent such as alcohols. Is obtained. By optimizing the boiling point and viscosity of the solvent, it is also possible to obtain a coating solution suitable for inkjet printing, for example, diethylene glycol derivatives such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monobutyl ether acetate, diethylene glycol diethyl ether, It can be obtained by substituting a part of dibasic acid ester and / or benzyl acetate with alkylphenol and / or alkenylphenol which is a solvent.

  In the patterning (laser trimming), the substrate coated with the coating liquid is dried at a temperature of 80 to 180 ° C. for 10 to 60 minutes, and then irradiated with a laser beam corresponding to the light absorption wavelength of the organic dye. This is done by destructive removal by instantaneous heating. In the case of laser firing, the irradiation intensity of the laser beam is adjusted so that the irradiated part is not destroyed. As described above, for example, a laser beam having a light wavelength of around 500 nm, 800 nm, or 1000 nm is used, but the laser beam is not particularly limited as long as it is a commonly used laser.

Heating and baking are performed by putting a substrate with a dry film patterned (laser trimming) as necessary into a baking furnace, heating to 400 to 800 ° C., and holding for 15 to 60 minutes. Although the firing temperature depends on the heat-resistant temperature of the base material, the conductivity of the ITO transparent conductive film increases as the firing temperature increases, so that the grain growth of the ITO particles is promoted and improved. preferable. Regarding the firing atmosphere, it is necessary to first carry out in an oxygen-containing atmosphere (for example, air atmosphere) for burning and decomposing the binder and the organic dye, but if the firing in a nitrogen atmosphere is used in combination, the carrier density increases greatly. The conductivity is improved.
Similarly, laser firing is performed by irradiating a dry film patterned (laser trimming) with a laser beam as necessary, and setting the irradiated portion to be, for example, several hundred degrees Celsius or higher. About atmosphere, it is the same as that of heat-firing. In laser firing, fine patterning can also be obtained by a pattern irradiation method in which only an irradiated portion is converted into a transparent conductive film, and a dry film in an unirradiated portion is removed (for example, dissolution in a solvent or the like).
[Example]

  Examples of the present invention will be specifically described below, but the present invention is not limited to these examples.

  9.10 g acetylacetone indium, 0.90 g acetylacetone tin, 34.96 g paratertiary butylphenol, 52.44 g dibasic acid ester (manufactured by DuPont Japan) are mixed, heated to 130 ° C. and stirred for 90 minutes to dissolve. After that, 2.60 g of hydroxypropylcellulose was added and dissolved by stirring for 90 minutes (solution A).

  VALIFAST RED 3304 (maximum absorption wavelength 530 nm) manufactured by Orient Chemical is used as an organic dye, dissolved in a mixed solution of 40 parts by weight of paratertiary butylphenol and 60 parts by weight of dibasic acid ester, and 1% by weight of VALIFAST RED 3304 is contained. An organic dye solution was prepared (Liquid B).

  4g of liquid A and 1g of liquid B are mixed, coating for forming transparent conductive film containing 8% by weight of acetylacetone indium and acetylacetone tin, 2.08% by weight of hydroxypropylcellulose, and 0.2% by weight of VALIFAST RED3304 as an organic dye A liquid was prepared. This coating solution was wire bar coated on a soda lime glass substrate to obtain a glass substrate with a coating film according to Example 1.

  A glass substrate with a coating film according to Example 2 was obtained in the same manner as in Example 1 except that VALIFAST RED 3306 (maximum absorption wavelength: 500 nm) manufactured by Orient Chemical was used as the organic dye.

  A glass substrate with a coating film according to Example 3 was obtained in the same manner as in Example 1 except that VALIFAST RED 3320 (maximum absorption wavelength 515 nm) manufactured by Orient Chemical was used as the organic dye.

  A glass substrate with a coating film according to Example 4 was obtained in the same manner as in Example 1 except that VALIFAST BLACK 1807 (maximum absorption wavelength 580 nm) manufactured by Orient Chemical was used as the organic dye.

  A glass substrate with a coating film according to Example 5 was obtained in the same manner as in Example 1 except that VALIFAST BROWN 2402 (maximum absorption wavelength: 430 nm) manufactured by Orient Chemical was used as the organic dye.

  A glass substrate with a coating film according to Example 6 was obtained in the same manner as in Example 1 except that NUBIAN BLACK PC-0850 (maximum absorption wavelength 575 nm) manufactured by Orient Chemical was used as the organic dye.

  A glass substrate with a coating film according to Example 7 was obtained in the same manner as in Example 1 except that Avicia PRO-JET 800NP (maximum absorption wavelength 775 nm) was used as the organic dye.

  A glass substrate with a coating film according to Example 8 was obtained in the same manner as in Example 1 except that PRO-JET 825LDI (maximum absorption wavelength 780 nm) manufactured by Avisia was used as the organic dye.

  A glass substrate with a coating film according to Example 9 was obtained in the same manner as in Example 1 except that Avicia PRO-JET 830NP (maximum absorption wavelength 810 nm) was used as the organic dye.

  A glass substrate with a coating film according to Example 10 was prepared in the same manner as in Example 1 except that PRO-JET 950NP (maximum absorption wavelength 940 nm) manufactured by Avisia was used as the organic dye.

  A glass substrate with a coating film according to Example 11 was obtained in the same manner as in Example 1 except that YKR-2200 (maximum absorption wavelength: 985 nm) manufactured by Yamamoto Kasei was used as the organic dye.

  A glass substrate with a coating film according to Example 12 was obtained in the same manner as in Example 1 except that YKR-3080 (maximum absorption wavelength: 1015 nm) manufactured by Yamamoto Kasei was used as the organic dye.

  A glass substrate with a coating film according to Example 13 was obtained in the same manner as in Example 1 except that ORASOL BLUE-GN (maximum absorption wavelength: 670 nm) manufactured by Ciba Specialty Chemicals was used as the organic dye.

A glass substrate with a coating film according to Example 14 was obtained in the same manner as in Example 1 except that VALIFAST BLUE 2620 (maximum absorption wavelength: 670 nm) manufactured by Orient Chemical was used as the organic dye.

(Comparative Example 1)

  4.0 g of liquid A is mixed with 1.0 g of a mixed solution of 40 parts by weight of para-tert-butylphenol and 60 parts by weight of dibasic acid ester, 8% by weight of acetylacetone indium and acetylacetone tin, and 2.08% by weight of hydroxypropylcellulose. The coating liquid for transparent conductive film formation which contains was prepared, the bar | burr bar coating was carried out on the soda-lime glass substrate, and the glass substrate with the coating film which concerns on the comparative example 1 was obtained.

  The glass substrate with a coating film according to each example obtained in this manner and the glass substrate with a coating film according to a comparative example were dried at 120 ° C. for 30 minutes, and the maximum was obtained using a spectrometer (U-4000) manufactured by Hitachi, Ltd. The light transmittance at the absorption wavelength was measured. The results are shown in Table 1.

The above-described transmittance is the transmittance of only the membrane, and is determined as follows. That is,
Membrane permeability (%)
= [(Transmittance measured for each transparent conductive substrate) / (transmittance of glass substrate)] × 100

  In the dry film | membrane which concerns on Examples 1-14 in Table 1, the dry film | membrane with which the light transmittance fell in the area | region of wavelength 300-1200 nm is formed, respectively, When irradiating the laser beam corresponding to each wavelength, the laser beam will be irradiated. Since it absorbs, patterning (trimming) of the coating film and laser baking are possible. On the other hand, in the dry film according to Comparative Example 1, the light transmittance in the wavelength region of 300 to 1200 nm is almost 100%, and it is transmitted even when irradiated with a laser beam. Can not.

Next, the dried film according to each of the above examples and the dried film according to Comparative Example 1 were baked at 550 ° C. for 30 minutes, the surface resistance value, visible light transmittance and haze value of the formed transparent conductive film, and the organic used. The light transmittance at the maximum absorption wavelength of the dye was measured with a surface resistance meter (MCP-T350) manufactured by Mitsubishi Chemical, a haze meter (HR-200) manufactured by Murakami Color Research Laboratory, and a spectrometer (U-4000) manufactured by Hitachi, Ltd. And measured. The results are shown in Table 2.
The dry film according to Example 12 was irradiated with a laser beam in a pattern and baked with a laser beam, and then the unirradiated part of the dry film was removed with an organic solvent to obtain a patterned transparent conductive film. The film characteristics of this transparent conductive film were similar to the results of Example 12 in Table 2.

    It turns out that the transparent electrically conductive film is formed, without impairing transparency and electroconductivity, for the coating liquid for forming a transparent electrically conductive film containing 0.05 to 2% by weight of the organic dye of the example.

If the coating liquid for forming a transparent conductive film of the present invention is used, a laser beam is absorbed at the stage of a dry film, so that patterning (trimming) and laser firing by laser irradiation are possible, and the organic dye in the coating liquid is Since it is burned and removed in the firing step, a transparent conductive film having transparency and conductivity equivalent to those of the conventional one can be formed.

Claims (11)

  A coating liquid for forming a transparent conductive film containing indium acetylacetone, organometallic compound for dopant, cellulose derivative, organic dye, alkylphenol and / or alkenylphenol, dibasic acid ester and / or benzyl acetate, for indium acetylacetone and dopant Transparent, characterized in that the total content with the organometallic compound is 1 to 30% by weight, the content of the cellulose derivative is 0.1 to 5% by weight, and the content of the organic dye is 0.05 to 2% by weight Coating liquid for forming a conductive film.   The coating liquid for forming a transparent conductive film according to claim 1, wherein the organic dye has absorption in a wavelength region of 300 to 1200 nm.   The total content of the said acetylacetone indium and the organometallic compound for dopants is 5 to 20 weight%, The coating liquid for transparent conductive film formation of Claim 1 or 2 characterized by the above-mentioned.   The content ratio of the acetylacetone indium and the organometallic compound for dopant is a weight ratio of acetylacetone indium / organotin compound = 99/1 to 80/20, according to any one of claims 1 to 3. Coating liquid for forming transparent conductive film.   The coating liquid for forming a transparent conductive film according to claim 1, wherein the organometallic compound for dopant is an organotin compound.   6. The coating liquid for forming a transparent conductive film according to claim 5, wherein the organic tin compound is acetylacetone tin.   The coating liquid for forming a transparent conductive film according to claim 1, wherein the cellulose derivative is hydroxypropylcellulose.   A method for producing a transparent conductive film, comprising: applying a coating liquid for forming a transparent conductive film according to any one of claims 1 to 7 on a substrate; drying the coating liquid; and firing at a temperature of 400 ° C or higher. .   A method for producing a transparent conductive film, comprising applying the coating liquid for forming a transparent conductive film according to any one of claims 1 to 7 on a substrate, drying the resultant, and then performing laser firing.   The method for producing a transparent conductive film according to claim 8 or 9, wherein the coating liquid for forming the transparent conductive film is applied on a substrate by a screen printing method or a wire bar coating method. The transparent conductive film obtained with the manufacturing method of the transparent conductive film of any one of Claims 8-10.