JP6690968B2 - Method for manufacturing transparent conductive substrate and lateral electric field type liquid crystal display panel with built-in touch panel function - Google Patents

Description

  The present invention relates to a method for manufacturing a transparent conductive substrate and a horizontal electric field type liquid crystal display panel with a built-in touch panel function, which includes the transparent conductive substrate manufactured by the manufacturing method.

  Liquid crystal display panels are used for small display devices such as various information equipment terminals and cameras, and in recent years, they have been used for large display devices such as televisions, taking advantage of their characteristics such as light weight, thinness, and low power consumption. ing. As a type of liquid crystal display panel, a vertical electric field method represented by a TN (twisted nematic) type was once dominant, but recently, a liquid crystal display panel called a lateral electric field method has become mainstream. There is.

  In a vertical electric field type liquid crystal display panel, one of the transparent substrates arranged to face each other with a liquid crystal layer in between is provided with a pixel electrode, and the other transparent substrate is provided with a common electrode. The alignment of the liquid crystal is controlled by an electric field generated between the pixel electrode and the common electrode, that is, an electric field perpendicular to the transparent substrate. On the other hand, in the configuration of the liquid crystal display panel of the horizontal electric field system, among the transparent substrates arranged to face each other via the liquid crystal layer, the display electrode and the reference electrode are mainly provided on the liquid crystal layer side of one transparent substrate. Is provided, and the liquid crystal layer is controlled by controlling the alignment of the liquid crystal by an electric field (lateral electric field, fringe electric field) generated between the display electrode and the reference electrode, that is, an electric field generated in parallel with the transparent substrate. It is designed to modulate transmitted light.

  The horizontal electric field type liquid crystal display panel has an advantage in that it has a wider viewing angle than the vertical electric field type liquid crystal display panel, but a problem that does not occur in the vertical electric field type liquid crystal display panel is that electrostatic discharge from outside or inside the liquid crystal display panel is a problem. However, there is a problem in that the display quality is deteriorated, such as light leakage when black is displayed due to such influences and external electromagnetic interference. This is because the horizontal electric field type liquid crystal display panel has a structure in which the display electrode and the reference electrode are integrated on one transparent substrate, and therefore has no conductive layer having a shield function against external static electricity and the like. This is because it is not configured.

  In order to solve such a problem, among the transparent substrates of the liquid crystal display panel, a transparent conductive layer is formed on the surface opposite to the liquid crystal layer of the transparent substrate far from the backlight unit, A technique of providing an electrostatic discharge (ESD) function has been proposed, and specifically, a method of forming an antistatic film containing ITO or the like as a conductive layer has been proposed (see Patent Document 1). With this method, an ESD function can be imparted to the horizontal electric field type liquid crystal display panel.

  On the other hand, recently, there is an increasing demand for a liquid crystal display device using a liquid crystal display panel having a touch panel function, as represented by a liquid crystal display device used for a smart phone or the like. The liquid crystal display panel with a touch panel function, which is currently in widespread use, is an external type in which a touch panel is placed outside the conventional liquid crystal display panel, but this external type makes the entire panel thicker and it is difficult to make the liquid crystal display device thinner. Then there is a problem. On the other hand, a liquid crystal display panel with a built-in touch panel function has been proposed as a built-in type in which a touch panel function is built in the liquid crystal display panel. A liquid crystal display panel with a built-in touch panel has a touch sensing function layer disposed between two glass substrates of the liquid crystal display panel, and has an advantage that the entire panel can be thinned. Therefore, there has been proposed a liquid crystal display panel in which the horizontal electric field type liquid crystal display panel and the liquid crystal display panel with a built-in touch panel function are combined (see Patent Document 2). Further, in Patent Document 2, for example, an electrostatic capacitance method is introduced as a touch sensing method used for the touch sensing function layer.

  Further, there are Patent Documents 3 to 6 as prior art documents related to the present invention.

JP, 2010-102020, A JP, 2011-137882, A JP 2000-196287 A JP, 2005-139026, A JP, 2006-339113, A JP 2012-25793 A

  However, in the conventional method of forming a transparent conductive film by applying a transparent conductive coating liquid to a transparent substrate of a liquid crystal display panel by spray coating or the like, the optical characteristics and the electrical characteristics of the transparent conductive film are set within a specific range. It was difficult to control, and it was difficult to stably form a transparent conductive film having uniform characteristics.

  Therefore, for example, in a liquid crystal display panel in which a horizontal electric field type liquid crystal display panel and a liquid crystal display panel with a built-in touch panel function in which a capacitance type touch sensing function layer is arranged are combined, a horizontal electric field type liquid crystal display panel is required. It has been found that when a conductive layer is provided on the liquid crystal display panel to provide the ESD function, the touch sensitivity may be lowered.

  The present invention solves the above problems and provides a method for producing a transparent conductive substrate capable of stably supplying a transparent substrate having a transparent conductive film in which optical characteristics and electrical characteristics are controlled in a specific range. Is.

The method for producing a transparent conductive substrate of the present invention includes a coating step of applying a transparent conductive coating composition to a transparent substrate, and a film forming step of forming a transparent conductive film on the transparent substrate, wherein the transparent The conductive coating composition contains chain conductive inorganic particles, an inorganic binder, a high boiling point solvent having a boiling point of 150 ° C. or higher, and a low boiling point solvent having a boiling point of 100 ° C. or lower, and the chain conductive inorganic material. The total amount of particles and the inorganic binder is 0.4% by mass or more and 1% by mass or less with respect to the total mass of the transparent conductive coating composition, and the content of the chain-like conductive inorganic particles is Based on the total mass of the chain-like conductive inorganic particles and the inorganic binder, 75 mass% or more and 85 mass% or less, the thickness of the transparent conductive film is 10 nm or more and 50 nm or less, the transparent conductive Resistivity of surface film , Characterized in that it is 1.1 × 10 ⁹ Ω / square or more 1.0 × ¹⁰ 10 Ω / square or less.

  Further, the horizontal electric field type liquid crystal display panel with a built-in touch panel function of the present invention includes the transparent conductive substrate manufactured by the method of manufacturing a transparent conductive substrate of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the transparent conductive substrate provided with the transparent conductive film which controlled the optical characteristic and electric characteristic in the specific range can be provided stably.

FIG. 1 is a schematic cross-sectional view showing an example of the transparent conductive substrate manufactured by the present invention.

(Method for producing transparent conductive substrate of the present invention)
First, a method for manufacturing the transparent conductive substrate of the present invention will be described.

The method for producing a transparent conductive substrate of the present invention includes a coating step of coating the transparent conductive coating composition on the transparent substrate and a film forming step of forming a transparent conductive film on the transparent substrate. Further, the transparent conductive coating composition contains chain conductive inorganic particles, an inorganic binder, a high boiling point solvent having a boiling point of 150 ° C. or higher, and a low boiling point solvent having a boiling point of 100 ° C. or lower, and the chain. Of the linear conductive inorganic particles and the inorganic binder is 0.4 mass% or more and 1 mass% or less based on the total mass of the transparent conductive coating composition. The content is 75% by mass or more and 85% by mass or less with respect to the total mass of the chain conductive inorganic particles and the inorganic binder, and the thickness of the transparent conductive film is 10 nm or more and 50 nm or less. The surface resistivity of the transparent conductive film is 1.1 × 10 ⁹ Ω / square or more and 1.0 × 10 ¹⁰ Ω / square or less.

  By setting the total amount of the chain-like conductive inorganic particles and the inorganic binder to be 0.4% by mass or more and 1% by mass or less based on the total mass of the transparent conductive coating composition, the transparent conductive coating composition The solid content concentration of the product is reduced, and in the coating step of coating the transparent conductive coating composition on the transparent substrate, a relatively thin coating film can be formed, and in the subsequent film forming step, the coating is relatively thin on the transparent substrate. A thin transparent conductive film can be formed. Thereby, the optical characteristics of the transparent conductive film can be improved.

  In addition, the content of the chain-like conductive inorganic particles is set to 75% by mass or more and 85% by mass or less with respect to the total mass of the chain-like conductive inorganic particles and the inorganic binder, whereby the inorganic system is relatively Since the content of the binder is decreased, that is, the content of the inorganic binder, which greatly affects the deterioration of the optical characteristics, is decreased, the optical characteristics of the transparent conductive film can be improved.

  Further, even if the thickness of the transparent conductive film is reduced, the content of the chain-like conductive inorganic particles is 75% by mass or more and 85% by mass or more with respect to the total mass of the chain-like conductive inorganic particles and the inorganic binder. As the mass% or less, by increasing the content of the chain-like conductive inorganic particles from the past, the increase in the surface resistivity of the formed transparent conductive film is suppressed, and the surface resistivity of the transparent conductive film is reduced. It can be controlled within a specific range.

  From the above, the total amount of the chain conductive inorganic particles and the inorganic binder is 0.4 mass% or more and 1 mass% or less with respect to the total mass of the transparent conductive coating composition. By controlling the content of the inorganic particles to 75% by mass or more and 85% by mass or less with respect to the total mass of the chain-like conductive inorganic particles and the inorganic binder, the optical characteristics and the electrical characteristics were controlled within specific ranges. A transparent conductive substrate provided with a transparent conductive film can be stably provided.

Next, the components contained in the transparent conductive coating composition used in the method for producing a transparent conductive substrate of the present invention will be described.
<Chain conductive inorganic particles>
The transparent conductive coating composition used in the present invention has a content of the chain-shaped conductive inorganic particles of 75% by mass or more and 85% by mass or less with respect to the total mass of the chain-shaped conductive inorganic particles and the inorganic binder. And This makes it possible to form a transparent conductive film having a surface resistivity of 1.1 × 10 ⁹ Ω / square or more and 1.0 × 10 ¹⁰ Ω / square or less.

  As the chain-like conductive inorganic particles, it is preferable to use those in which 2 to 50 primary particles having a particle diameter of 2 to 30 nm are connected, and more preferably 3 to 20 are connected. If the number of primary particles connected to each other exceeds 50, the haze value of the transparent conductive film tends to increase due to particle scattering. When the number of primary particles having the above particle diameters connected to each other is less than 2, the particles become non-chained and it becomes difficult to form a conductive network between the inorganic particles, and the conductivity of the transparent conductive film is lowered.

  The particle diameter and the number of connections are, for example, those obtained by diluting the transparent conductive coating composition with a low boiling point solvent and thinly coating the transparent conductive coating composition on various substrates with a film thickness of 2 to 10 nm using a transmission electron microscope ( It can be determined by observing and measuring the particle diameter and the number of connections of individual particles constituting the chain-like conductive inorganic particles by TEM).

  The chain-like conductive inorganic particles are not particularly limited as long as they are chain particles having both transparency and conductivity, and examples thereof include metal particles, carbon particles, conductive metal oxide particles, and conductive nitride particles. Can be used. Among them, conductive metal oxide particles having both transparency and conductivity are preferable. Examples of the conductive metal oxide particles include tin oxide particles, antimony oxide particles, antimony-containing tin oxide (ATO) particles, tin-containing indium oxide (ITO) particles, phosphorus-containing tin oxide (PTO) particles, and aluminum-containing zinc oxide ( Examples thereof include metal oxide particles such as AZO) particles and gallium-containing zinc oxide (GZO) particles. The conductive metal oxide particles may be used alone or in combination of two or more kinds. Further, the chain-like conductive inorganic particles preferably include at least one selected from the group consisting of ATO particles, ITO particles and PTO particles. This is because these conductive inorganic particles are excellent in transparency, conductivity and chemical properties, and even when formed into a transparent conductive film, high light transmittance and conductivity can be realized.

  The method for producing the chain-like conductive inorganic particles is not particularly limited, but, for example, the above-mentioned Patent Document 3 (JP 2000-196287A), Patent Document 4 (JP 2005-139026A), and Patent Document 5 are mentioned. (Japanese Patent Application Laid-Open No. 2006-339113) and Patent Document 6 (Japanese Patent Application Laid-Open No. 2012-25793) can be used.

<Inorganic binder>
The inorganic binder used in the present invention is not particularly limited as long as it can disperse the chain-like conductive inorganic particles to form a coating film. The content of the inorganic binder is preferably 15% by mass or more with respect to the total mass of the chain conductive inorganic particles and the inorganic binder. This is because if it is less than 15% by mass, the strength of the transparent conductive film tends to decrease.

As the inorganic binder, for example, alkoxysilane can be used. More specifically, the alkoxysilane is a compound in which 3 to 4 alkoxy groups are bonded to silicon, and when dissolved in water, it is polymerized to form a high molecular weight SiO ₂ body linked by —OSiO—. Can be used.

  The above-mentioned alkoxysilane preferably contains at least one polyfunctional alkoxysilane selected from the group consisting of tetraalkoxysilane, trialkoxysilane, dialkoxysilane and alkoxysilane oligomer. The alkoxysilane oligomer is a high-molecular weight alkoxysilane formed by condensation of alkoxysilane monomers with each other, and refers to an oligomer having two or more siloxane bonds (-OSiO-) in one molecule. . The number of bonds is preferably 2 to 20.

  Examples of the tetraalkoxysilane include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraiso-propoxysilane, tetra-t-butoxysilane, and the like, which are tetra-substituted with an alkoxy group having 1 to 4 carbon atoms. To be

  Examples of the trialkoxysilane are tri-substituted with an alkoxy group having 1 to 4 carbon atoms such as trimethoxysilane, triethoxysilane, tripropoxysilane, tributoxysilane, triiso-propoxysilane, and tri-L-butoxysilane. In addition, silanes such as "KBM-13 (methyltrimethoxysilane)" and "KBE-13 (methyltriethoxysilane)" partially substituted with an alkyl group can be mentioned.

  Examples of the dialkoxysilane include dimethyldimethoxysilane, diphenyldimethoxysilane, dimethyldiethoxysilane, diphenyldiethoxysilane, and other silanes disubstituted with an alkoxy group having 1 to 4 carbon atoms, "KBM-22 (dimethyldimethoxysilane). Silane) "," KBE-22 (dimethyldiethoxysilane) "and the like, which are partially substituted with an alkyl group.

  Examples of the alkoxysilane oligomer include a relatively low molecular weight alkoxysilane oligomer having both an organic group and an alkoxysilyl group. As a specific example, "X-40-2308", "X-40-9238", "X-40-9247", "KR-401N", "KR-510", "KR-9218" manufactured by Shin-Etsu Chemical Co., Ltd. , “Ethyl silicate 40”, “Ethyl silicate 48”, “Methyl silicate 51”, “Methyl silicate 53A” and the like manufactured by Colcoat Co., Ltd.

  Among the above specific examples of alkoxysilane, in order to form a transparent conductive film having higher hardness, tetraalkoxysilane and trialkoxysilane are used in combination, and trialkoxysilane or dialkoxysilane partially substituted with an alkyl group. An alkoxysilane oligomer whose functional group is an alkoxysilyl group is preferred. By using these, the hardness of the transparent conductive film is increased by the three-dimensional cross-linking that promotes the siloxane bond between the binder molecules, and the risk of cracking in the transparent conductive film due to aging is further reduced, and This is because the adhesiveness with the substrate can be further enhanced.

<High boiling point solvent>
The high-boiling solvent used in the present invention is a solvent having a boiling point of 150 ° C. or higher, as long as it dissolves the inorganic binder component and can be removed by a drying step after coating, for example, ethylene glycol, dimethyl sulfoxide, N-methylpyrrolidone, N-ethylpyrrolidone, N-methylformamide, methylisobutylketone, 1,2-propanediol, N, N-dimethylaniline, cresol, nitrobenzene, ethylene glycol, etc. can be used, but the evaporation rate and coating liquid From the viewpoint of storage stability, dimethyl sulfoxide is preferable.

  The content of the high boiling point solvent is preferably 5% by mass or more and 20% by mass or less based on the total mass of the conductive coating composition.

<Low boiling point solvent>
The low boiling point solvent used in the present invention is a solvent having a boiling point of 100 ° C. or lower, and examples thereof include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, propylene glycol monomethyl ether acetate and methyl ethyl ketone. , Tetrahydrofuran, acetone, dioxane, ethyl acetate, chloroform, acetonitrile, pyridine, acetic acid, water and the like can be used, but ethyl alcohol or isopropyl alcohol is preferable from the viewpoint of drying property and storage stability of the coating solution. By using the low boiling point solvent, the dispersibility of the chain-like conductive inorganic particles is improved.

  The content of the low boiling point solvent is preferably 80% by mass or more and 95% by mass or less based on the total mass of the conductive coating composition.

<Leveling agent>
A leveling agent can be further added to the transparent conductive coating composition used in the present invention. This ensures the surface smoothness of the transparent conductive film. As the leveling agent, for example, polyether-modified polydimethylsiloxane, dipropylene glycol monomethyl ether or the like can be used. The content of the leveling agent may be about 0.01 to 5.0 mass% with respect to the total mass of the conductive coating composition.

<Preparation method>
The method for preparing the transparent conductive coating composition used in the present invention is not particularly limited as long as the above respective components are mixed and the chain conductive inorganic particles can be dispersed in the inorganic binder and the solvent, for example, Ball mill, sand mill, pico mill, mechanical treatment with media such as paint conditioner, or ultrasonic dispersion machine, homogenizer, disperser, jet mill, etc. may be used to mix and disperse the above components. it can.

  Next, each step of the method for producing a transparent conductive substrate of the present invention will be described.

<Coating process>
In the coating step of the present invention, the transparent conductive coating composition is coated on a transparent substrate.

  The coating method of the transparent conductive coating composition is not particularly limited as long as it is a coating method capable of forming a smooth coating film. For example, spin coating, roll coating, die coating, air knife coating, blade coating, reverse coating, gravure coating, coating methods such as micro gravure coating, or gravure printing, screen printing, offset printing, printing methods such as inkjet printing, spray coating, Although a coating method such as slit coating or dip coating can be used, the conductive coating composition used in the present invention has a high solvent content and low viscosity, and therefore spin coating or spray coating is preferable from the viewpoint of coating efficiency. .

  As the transparent substrate, a glass substrate, a transparent resin substrate or the like can be used, but a glass substrate of a liquid crystal display panel is preferable.

<Film forming process>
In the film forming step of the present invention, a transparent conductive film is formed by drying the coating film formed of the transparent conductive coating composition applied on the transparent substrate to remove the solvent. The drying conditions are not particularly limited, and the temperature and time at which the solvent can be removed can be set appropriately.

  Next, the transparent conductive film produced by the present invention will be described.

  The thickness of the transparent conductive film produced by the present invention is set to 10 nm or more and 50 nm or less. Thereby, the haze value of the transparent conductive film can be 0.2% or less, and the total light transmittance of the transparent conductive film can be 99.1% or more and 99.9% or less.

Further, the transparent conductive film is formed by using the transparent conductive coating composition to control the surface resistivity to 1.1 × 10 ⁹ Ω / square or more and 1.0 × 10 ¹⁰ Ω / square or less. can do.

  In addition, the transparent conductive film can have a pencil hardness of 5 to 9H by being formed using the transparent conductive coating composition, which prevents scratches in the manufacturing process and reduces yield. Can be prevented.

  Next, a transparent conductive substrate manufactured by the method for manufacturing a transparent conductive substrate of the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of the transparent conductive substrate manufactured by the present invention. In FIG. 1, the transparent conductive substrate 10 includes a glass substrate 11 such as a liquid crystal display panel and a transparent conductive film 12 formed thereon.

(Lateral electric field type LCD panel with built-in touch panel function)
Next, a horizontal electric field type liquid crystal display panel with a built-in touch panel function of the present invention will be described.

  A horizontal electric field type liquid crystal display panel with a built-in touch panel function of the present invention is characterized by including the transparent conductive substrate manufactured by the method for manufacturing a transparent conductive substrate of the present invention. Since the horizontal electric field type liquid crystal display panel with a built-in touch panel function of the present invention is provided with the transparent conductive substrate manufactured by the present invention, an ESD function can be provided without lowering touch sensitivity.

  Hereinafter, the present invention will be described in detail based on examples. However, the present invention is not limited to the following examples. Further, in the following, “part” means “part by mass”.

(Example 1)
<Preparation of coating liquid>
The following components (1) to (5) were placed in a plastic bottle in the following amounts and stirred to prepare a coating liquid.

(1) Chain-like ATO particles: 0.42 parts (2) Alkoxysilane (inorganic binder: "X40-2308" manufactured by Shin-Etsu Chemical Co., Ltd.): 0.10 parts (3) Dimethyl sulfoxide (high boiling point solvent): 5 0.000 parts (4) Ethyl alcohol (low boiling solvent): 94.38 parts (5) Mixed solution of 15.0 parts of polyether-modified polydimethylsiloxane and 85.0 parts of dipropylene glycol monomethyl ether (leveling agent: VIC “BYK-337” manufactured by Chemie Japan): 0.10 part

  The content of the nonvolatile solid components (chain ATO particles and alkoxysilane) of the coating liquid is 0.52% by mass, and the content of chain ATO particles is 80% by mass with respect to the total amount of the chain ATO particles and alkoxysilane. Met.

<Preparation of transparent conductive substrate>
The coating liquid was applied by spray coating on a glass substrate having a length of 10 cm, a width of 10 cm, and a thickness of 0.7 mm. The spray gun used was a pulse spray manufactured by Nordson Co., Ltd., the needle opening was set to 0.15 mm, and the extrusion pressure of the liquid was adjusted so that the discharge liquid amount was 10.0 g / min. The distance between the gun and the substrate was 100 mm, the coating speed was 600 mm per second, the stacking pitch was 15.0 mm, and the pressure of atomizing air and swirl air was 0.05 MPa. The coating area was 20 cm square, and the substrate was placed with the substrate at the center of the coating area. The obtained coating film was dried in a drier at 120 ° C. for 1 hour to prepare a transparent conductive substrate of Example 1 in which a transparent conductive film was provided on a glass substrate.

(Example 2)
<Preparation of coating liquid>
The following components (1) to (5) were placed in a plastic bottle in the following amounts and stirred to prepare a coating liquid.

(1) Chain ATO particles: 0.42 parts (2) Alkoxysilane (inorganic binder: "X40-2308" manufactured by Shin-Etsu Chemical Co., Ltd.): 0.10 parts (3) Dimethyl sulfoxide (high boiling point solvent): 7 .50 parts (4) Ethyl alcohol (low boiling point solvent): 91.88 parts (5) Mixed solution of 15.0 parts of polyether-modified polydimethylsiloxane and 85.0 parts of dipropylene glycol monomethyl ether (leveling agent: BIC “BYK-337” manufactured by Chemie Japan): 0.10 part

  The content of the nonvolatile solid components (chain ATO particles and alkoxysilane) of the coating liquid is 0.52% by mass, and the content of chain ATO particles is 80% by mass with respect to the total amount of the chain ATO particles and alkoxysilane. Met.

  Next, using the above coating liquid, a transparent conductive substrate of Example 2 was produced in the same manner as in Example 1 except that the overlapping pitch was changed to 17.5 mm.

(Example 3)
<Preparation of coating liquid>
The following components (1) to (5) were placed in a plastic bottle in the following amounts and stirred to prepare a coating liquid.

(1) Chain ATO particles: 0.42 parts (2) Alkoxysilane (inorganic binder: "X40-2308" manufactured by Shin-Etsu Chemical Co., Ltd.): 0.10 parts (3) Dimethyl sulfoxide (high boiling point solvent): 15 0.000 parts (4) Ethyl alcohol (low-boiling solvent): 84.38 parts (5) Mixed solution of 15.0 parts of polyether-modified polydimethylsiloxane and 85.0 parts of dipropylene glycol monomethyl ether (leveling agent: BIC “BYK-337” manufactured by Chemie Japan): 0.10 part

  The content of the nonvolatile solid components (chain ATO particles and alkoxysilane) of the coating liquid is 0.52% by mass, and the content of chain ATO particles is 80% by mass with respect to the total amount of the chain ATO particles and alkoxysilane. Met.

  Next, a transparent conductive substrate of Example 3 was produced in the same manner as in Example 1 except that the coating liquid was used and the overlapping pitch was changed to 20.0 mm.

(Example 4)
<Preparation of coating liquid>
The following components (1) to (5) were placed in a plastic bottle in the following amounts and stirred to prepare a coating liquid.

(1) Chain-like ATO particles: 0.39 part (2) Alkoxysilane (inorganic binder: "X40-2308" manufactured by Shin-Etsu Chemical Co., Ltd.): 0.13 part (3) Dimethyl sulfoxide (high boiling solvent): 7 .50 parts (4) Ethyl alcohol (low boiling point solvent): 91.88 parts (5) Mixed solution of 15.0 parts of polyether-modified polydimethylsiloxane and 85.0 parts of dipropylene glycol monomethyl ether (leveling agent: BIC “BYK-337” manufactured by Chemie Japan): 0.10 part

  The content of the nonvolatile solid components (chain ATO particles and alkoxysilane) in the coating liquid is 0.52% by mass, and the content of chain ATO particles is 75% by mass with respect to the total amount of the chain ATO particles and alkoxysilane. Met.

  Next, a transparent conductive substrate of Example 4 was produced in the same manner as in Example 1 except that the coating liquid was used and the overlapping pitch was changed to 17.5 mm.

(Example 5)
<Preparation of coating liquid>
The following components (1) to (5) were placed in a plastic bottle in the following amounts and stirred to prepare a coating liquid.

(1) Chain ATO particles: 0.43 part (2) Alkoxysilane (inorganic binder: "X40-2308" manufactured by Shin-Etsu Chemical Co., Ltd.): 0.09 part (3) Dimethyl sulfoxide (high boiling point solvent): 7 .50 parts (4) Ethyl alcohol (low boiling point solvent): 91.88 parts (5) Mixed solution of 15.0 parts of polyether-modified polydimethylsiloxane and 85.0 parts of dipropylene glycol monomethyl ether (leveling agent: BIC “BYK-337” manufactured by Chemie Japan): 0.10 part

  The content of the nonvolatile solid components (chain ATO particles and alkoxysilane) of the coating liquid was 0.52% by mass, and the content of chain ATO particles was 83% by mass with respect to the total amount of the chain ATO particles and alkoxysilane. Met.

  Next, a transparent conductive substrate of Example 5 was produced in the same manner as in Example 1 except that the coating liquid was used and the overlapping pitch was changed to 17.5 mm.

(Example 6)
<Preparation of coating liquid>
The following components (1) to (5) were placed in a plastic bottle in the following amounts and stirred to prepare a coating liquid.

(1) Chain ATO particles: 0.42 part (2) Alkoxysilane (inorganic binder: "X40-2308" manufactured by Shin-Etsu Chemical Co., Ltd.): 0.07 part (3) Dimethyl sulfoxide (high boiling point solvent): 7 50 parts (4) Ethyl alcohol (low-boiling solvent): 91.91 parts (5) Mixed solution of 15.0 parts of polyether-modified polydimethylsiloxane and 85.0 parts of dipropylene glycol monomethyl ether (leveling agent: BIC “BYK-337” manufactured by Chemie Japan): 0.10 part

  The content of the nonvolatile solid components (chain ATO particles and alkoxysilane) of the coating liquid is 0.49% by mass, and the content of chain ATO particles is 85% by mass with respect to the total amount of the chain ATO particles and alkoxysilane. Met.

  Next, using the above coating liquid, a transparent conductive substrate of Example 6 was produced in the same manner as in Example 1 except that the overlapping pitch was changed to 17.5 mm.

(Comparative Example 1)
<Preparation of coating liquid>
The following components (1) to (5) were placed in a plastic bottle in the following amounts and stirred to prepare a coating liquid.

(1) Chain ATO particles: 1.40 parts (2) Alkoxysilane (inorganic binder: "X40-2308" manufactured by Shin-Etsu Chemical Co., Ltd.): 1.71 parts (3) Dimethyl sulfoxide (high boiling solvent): 7 50 parts (4) Ethyl alcohol (low boiling solvent): 89.29 parts (5) Mixed solution of 15.0 parts of polyether-modified polydimethylsiloxane and 85.0 parts of dipropylene glycol monomethyl ether (leveling agent: VIC “BYK-337” manufactured by Chemie Japan): 0.10 part

  The content of the nonvolatile solid components (chain ATO particles and alkoxysilane) of the coating liquid was 3.11% by mass, and the content of chain ATO particles was 45% by mass with respect to the total amount of the chain ATO particles and alkoxysilane. Met.

  Next, a transparent conductive substrate of Comparative Example 1 was produced in the same manner as in Example 1 except that the coating liquid was used and the overlapping pitch was changed to 5.0 mm.

(Comparative example 2)
<Preparation of coating liquid>
The following components (1) to (5) were placed in a plastic bottle in the following amounts and stirred to prepare a coating liquid.

(1) Chain ATO particles: 1.40 parts (2) Alkoxysilane (inorganic binder: "X40-2308" manufactured by Shin-Etsu Chemical Co., Ltd.): 1.71 parts (3) Dimethyl sulfoxide (high boiling point solvent): 3 0.000 parts (4) Ethyl alcohol (low-boiling solvent): 93.79 parts (5) Mixture of 15.0 parts of polyether-modified polydimethylsiloxane and 85.0 parts of dipropylene glycol monomethyl ether (leveling agent: BIC “BYK-337” manufactured by Chemie Japan): 0.10 part

  The content of the nonvolatile solid components (chain ATO particles and alkoxysilane) of the coating liquid was 3.11% by mass, and the content of chain ATO particles was 45% by mass with respect to the total amount of the chain ATO particles and alkoxysilane. Met.

  Next, a transparent conductive substrate of Comparative Example 2 was produced in the same manner as in Example 1, except that the coating liquid was used and the overlapping pitch was changed to 10.0 mm.

(Comparative example 3)
<Preparation of coating liquid>
The following components (1) to (5) were placed in a plastic bottle in the following amounts and stirred to prepare a coating liquid.

(1) Chain ATO particles: 0.70 part (2) Alkoxysilane (inorganic binder: "X40-2308" manufactured by Shin-Etsu Chemical Co., Ltd.): 0.38 part (3) Dimethyl sulfoxide (high boiling point solvent): 7 50 parts (4) Ethyl alcohol (low-boiling solvent): 91.32 parts (5) Mixed solution of 15.0 parts of polyether-modified polydimethylsiloxane and 85.0 parts of dipropylene glycol monomethyl ether (leveling agent: BIC “BYK-337” manufactured by Chemie Japan): 0.10 part

  The content of the nonvolatile solid component (chain ATO particles and alkoxysilane) of the coating liquid is 1.08% by mass, and the content of chain ATO particles is 65% by mass with respect to the total amount of the chain ATO particles and alkoxysilane. Met.

  Next, a transparent conductive substrate of Comparative Example 3 was produced in the same manner as in Example 1 except that the above coating liquid was used.

(Comparative example 4)
<Preparation of coating liquid>
The following components (1) to (5) were placed in a plastic bottle in the following amounts and stirred to prepare a coating liquid.

(1) Chain ATO particles: 0.70 part (2) Alkoxysilane (inorganic binder: "X40-2308" manufactured by Shin-Etsu Chemical Co., Ltd.): 0.30 part (3) Dimethyl sulfoxide (high boiling point solvent): 25 0.000 parts (4) Ethyl alcohol (low-boiling solvent): 73.90 parts (5) Mixed solution of 15.0 parts of polyether-modified polydimethylsiloxane and 85.0 parts of dipropylene glycol monomethyl ether (leveling agent: BIC “BYK-337” manufactured by Chemie Japan): 0.10 part

  The content of the nonvolatile solid components (chain ATO particles and alkoxysilane) in the coating liquid is 1.00% by mass, and the content of chain ATO particles is 70% by mass with respect to the total amount of the chain ATO particles and alkoxysilane. Met.

  Next, a transparent conductive substrate of Comparative Example 4 was produced in the same manner as in Example 1 except that the above-mentioned coating liquid was used, the discharge liquid amount was changed to 5.0 g / min, and the overlapping pitch was changed to 10.0 mm.

(Comparative example 5)
<Preparation of coating liquid>
The following components (1) to (5) were placed in a plastic bottle in the following amounts and stirred to prepare a coating liquid.

(1) Chain ATO particles: 0.70 part (2) Alkoxysilane (inorganic binder: "X40-2308" manufactured by Shin-Etsu Chemical Co., Ltd.): 0.30 part (3) Dimethyl sulfoxide (high boiling solvent): 7 .50 parts (4) Ethyl alcohol (low boiling point solvent): 91.40 parts (5) Mixed solution of 15.0 parts of polyether-modified polydimethylsiloxane and 85.0 parts of dipropylene glycol monomethyl ether (leveling agent: BIC “BYK-337” manufactured by Chemie Japan): 0.10 part

  The content of the nonvolatile solid components (chain ATO particles and alkoxysilane) in the coating liquid is 1.00% by mass, and the content of the chain ATO particles is 70% by mass with respect to the total amount of the chain ATO particles and alkoxysilane. Met.

  Next, a transparent conductive substrate of Comparative Example 5 was prepared in the same manner as in Example 1 except that the coating liquid was used and the overlapping pitch was changed to 10.0 mm.

(Comparative example 6)
<Preparation of coating liquid>
The following components (1) to (5) were placed in a plastic bottle in the following amounts and stirred to prepare a coating liquid.

(1) Chain-like ATO particles: 0.42 parts (2) Alkoxysilane (inorganic binder: "X40-2308" manufactured by Shin-Etsu Chemical Co., Ltd.): 0.05 parts (3) Dimethyl sulfoxide (high boiling point solvent): 7 50 parts (4) Ethyl alcohol (low boiling solvent): 91.93 parts (5) Mixed solution of 15.0 parts of polyether-modified polydimethylsiloxane and 85.0 parts of dipropylene glycol monomethyl ether (leveling agent: VIC “BYK-337” manufactured by Chemie Japan): 0.10 part

  The content of the nonvolatile solid components (chain ATO particles and alkoxysilane) in the coating liquid was 0.46% by mass, and the content of chain ATO particles was 90% by mass with respect to the total amount of the chain ATO particles and alkoxysilane. Met.

  Next, a transparent conductive substrate of Comparative Example 6 was produced in the same manner as in Example 1 except that the amount of discharged liquid was changed to 5.0 g / min and the overlapping pitch was changed to 23.0 mm using the above coating liquid.

  Next, the coating properties, film thickness, surface resistivity, haze value, total light transmittance, pencil hardness and reliability of each of the above transparent conductive substrates were measured or evaluated as follows.

<Coating properties>
The presence or absence of coating unevenness of the transparent conductive film was observed. When there was no coating unevenness, the coating property was judged to be good, and when there was coating unevenness, the coating property was judged to be poor.

<Film thickness>
The transparent conductive substrate was cut and the cross-section was observed with a scanning electron microscope (SEM, "S-4500" manufactured by Hitachi, Ltd.) to measure the film thickness of the transparent conductive film.

<Surface resistivity>
The initial surface resistivity of the transparent conductive film was measured using a surface resistance meter (“HIRESTA MCP-HT450” manufactured by Mitsubishi Chemical Corporation, applied voltage: 10 V).

<Haze value and total light transmittance>
The haze value and total light transmittance of only the transparent conductive film were measured using a photometer "Hazemeter NDH2000" manufactured by Nippon Denshoku Industries Co., Ltd.

<Pencil hardness>
The pencil hardness of the transparent conductive film was measured using a surface property tester “HEIDON-14DR” manufactured by Shinto Kagaku Co., Ltd.

<Reliability>
The surface resistivity of the transparent conductive film after the transparent conductive substrate was kept for 1000 hours in an environment of a temperature of 60 ° C. and a relative humidity of 90% was measured in the same manner as above, and the surface resistivity after a high temperature and high humidity test was performed. And Next, the change rate of the surface resistivity was obtained from the following formula, and when the change rate was less than 100%, the reliability was judged to be good, and when the change rate was 100% or more, the reliability was judged to be poor.
Rate of change (%) = (| initial surface resistivity-surface resistivity after high temperature and high humidity test | / initial surface resistivity) x 100

  The results of the above measurements are shown in Table 1 together with the solid content concentration of the coating liquid and the content of ATO particles in the transparent conductive film.

  From Table 1, it can be seen that the transparent conductive substrates of Examples 1 to 6 of the present invention obtained excellent results in all of coating properties, surface resistivity, haze value, total light transmittance, pencil hardness and reliability. I understand.

  On the other hand, in Comparative Examples 1 and 3 in which the solid content concentration exceeded 1 mass% and the ATO content fell below 75 mass%, the pencil hardness and reliability were poor, and the solid content concentration exceeded 1 mass% and the ATO content Is less than 75% by mass, Comparative Example 2 is poor in coating properties, total light transmittance, pencil hardness and reliability. In Comparative Example 4 in which the ATO content is less than 75% by mass, coating properties, pencil hardness and reliability are low. Inferior property, in Comparative Example 5 in which the ATO content was less than 75% by mass, the pencil hardness and reliability were inferior, and in Comparative Example 6 in which the ATO content exceeded 85% by mass, coating properties, pencil hardness and reliability Was inferior.

  INDUSTRIAL APPLICABILITY According to the present invention, it is possible to stably supply a transparent conductive substrate in which optical characteristics and electrical characteristics are controlled within a specific range, and thus, for example, a horizontal electric field method with a touch panel function including a capacitive touch sensing function layer. In the liquid crystal panel, it is possible to provide a horizontal electric field type liquid crystal display panel with a built-in touch panel function, which has both an ESD function and a touch panel function, and includes a transparent conductive substrate having specific optical characteristics and specific electrical characteristics.

10 Transparent Conductive Substrate 11 Glass Substrate 12 Transparent Conductive Film

Claims (11)

An applying step of applying the transparent conductive coating composition to a transparent substrate,
A film forming step of forming a transparent conductive film on the transparent substrate,
The transparent conductive coating composition contains chain conductive inorganic particles, an inorganic binder, a high boiling point solvent having a boiling point of 150 ° C. or higher, and a low boiling point solvent having a boiling point of 100 ° C. or lower,
The total amount of the chain-like conductive inorganic particles and the inorganic binder is 0.4 mass% or more and 0.49 mass% or less with respect to the total mass of the transparent conductive coating composition,
The content of the chain-shaped conductive inorganic particles is, relative to the total mass of the chain-shaped conductive inorganic particles and the inorganic binder, 75% by mass or more and 85% by mass or less,
The thickness of the transparent conductive film is 10 nm or more and 50 nm or less,
The method for producing a transparent conductive substrate, wherein the surface resistivity of the transparent conductive film is 1.1 × 10 ⁹ Ω / square or more and 1.0 × 10 ¹⁰ Ω / square or less.   The content of the high-boiling point solvent is 5% by mass or more and 20% by mass or less with respect to the total mass of the transparent conductive coating composition, and the content of the low-boiling point solvent is the transparent conductive coating composition. The method for producing a transparent conductive substrate according to claim 1, wherein the content is 80% by mass or more and 95% by mass or less based on the total mass of the above.   The method for producing a transparent conductive substrate according to claim 1, wherein the coating in the coating step is performed by spin coating or spray coating.   The haze value of the said transparent conductive film is 0.2% or less, The manufacturing method of the transparent conductive substrate of any one of Claims 1-3.   The total light transmittance of the said transparent conductive film is 99.1% or more and 99.9% or less, The manufacturing method of the transparent conductive substrate of any one of Claims 1-4.   The method for manufacturing a transparent conductive substrate according to claim 1, wherein the transparent substrate is a glass substrate.   The chain-like conductive inorganic particles include at least one kind of particles selected from the group consisting of antimony-containing tin oxide particles, tin-containing indium oxide particles and phosphorus-containing tin oxide particles. A method for producing a transparent conductive substrate as described above.   The method for producing a transparent conductive substrate according to claim 1, wherein the inorganic binder is alkoxysilane.   The method for producing a transparent conductive substrate according to claim 1, wherein the high boiling point solvent is dimethyl sulfoxide.   The method for producing a transparent conductive substrate according to claim 1, wherein the low boiling point solvent is ethyl alcohol or isopropyl alcohol.   A horizontal electric field type liquid crystal display panel with a built-in touch panel function, comprising the transparent conductive substrate manufactured by the method for manufacturing a transparent conductive substrate according to claim 1.

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