JPH07168196A - Laminated transparent electrically conductive base material and its production - Google Patents

Abstract

PURPOSE:To provide a laminated transparent electrically conductive base material suitable for forming a transparent electrode having a transparent insulating layer on the surface by etching, capable of easily preventing the change of electric resistance of a transparent electrically conductive film in a production process and easily attaining relatively high surface precision and having the surface of transparent insulating layer high in electrical insulation. CONSTITUTION:The laminated transparent electrically conductive base material is provided at least with a transparent base material, the transparent electrically conductive film on one main surface of the transparent base material directly or with an under coating layer and the transparent insulating layer formed on the transparent electrically conductive film and the transparent insulating layer is composed of an acid soluble-alkali resistant inorganic compound.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated transparent conductive substrate suitable as a material for producing transparent electrodes for liquid crystal display devices and the like.

[0002]

2. Description of the Related Art As a drive electrode for a liquid crystal display element, an electroluminescence display element (hereinafter abbreviated as an EL display element), or an electrode for manufacturing a color filter by an electrodeposition method, ITO or the like has been conventionally used. Transparent electrodes are used. These transparent electrodes are generally
After forming a transparent conductive film for transparent electrodes on a transparent substrate such as a glass substrate or transparent polymer film, this transparent conductive film is formed into a desired shape by an etching method using a predetermined mask (resist film) It is manufactured by doing. Then, as a material suitable for obtaining such a transparent electrode, a material obtained by forming a transparent conductive film on a transparent glass substrate (hereinafter, referred to as laminated transparent conductive glass), a transparent polymer film (including a sheet) ) A film having a transparent conductive film formed thereon (hereinafter referred to as a laminated transparent conductive film) has been developed (hereinafter, these are collectively referred to as a laminated transparent conductive substrate).

As described above, the laminated transparent conductive base material has the transparent base material and the transparent conductive film as essential members, but if necessary, an inorganic oxide, an organic compound or an organic compound may be provided on the transparent conductive film. A transparent protective film made of a polymer or the like is provided. This transparent protective film is used to improve the abrasion resistance and scratch resistance of the transparent conductive film (transparent electrode), prevent the generation of fine cracks in the transparent conductive film (transparent electrode) during etching, and are used for etching. The mask (resist film) is provided for the purpose of preventing the conductivity of the transparent conductive film (transparent electrode) from being lowered due to peeling using the alkaline solution.

The laminated transparent conductive substrate having a transparent protective layer is useful for achieving the above-mentioned objects, but on the other hand, it is difficult to etch with an acid, which causes a problem such as etching failure. Many have. One that does not have such drawbacks is a laminated type in which a protective layer (top coat layer) made of a polymer thin film of 1 μm or less that is acid-soluble and has alkali resistance is formed on a transparent conductive film by a coating method. A transparent conductive substrate is known (see Japanese Patent Application Laid-Open No. 61-16851).

By the way, the recent development of the liquid crystal display device is remarkable, and nowadays it is actively introduced to OA equipments such as personal computers and word processors as a display device replacing the CRT (CRT). In this liquid crystal display device, improvement in response is still desired today, and as one method for improving the response, attempts have recently been made to reduce the cell gap of the liquid crystal cell.

[0006]

In the liquid crystal display element, an alignment film is usually disposed inside each of the two transparent electrodes facing each other (on the liquid crystal side), and the cell gap of the liquid crystal cell is a spacer. Although it is maintained by introducing (polymer particles and the like) into the liquid crystal cell, it is difficult to uniformly dispose this spacer in the liquid crystal cell. Therefore, when the cell gap is reduced, it is likely that two transparent electrodes facing each other in the liquid crystal display element locally contact each other directly or through the alignment film. And if there is such contact,
Even if the alignment film is interposed, unnecessary conduction is generated between the two transparent electrodes, and a display defect is likely to occur.

The above-mentioned display failure can be prevented by providing an inorganic or organic transparent electrically insulating layer on the transparent electrode. However, after the transparent electrode having a desired shape is obtained by an etching method, this transparent Providing a transparent electrical insulation layer on the electrodes is useful for producing fine cracks in the transparent conductive film (transparent electrode) during etching and for removing the mask (resist film) used for etching with an alkaline solution. It is not possible to prevent the conductivity of the transparent conductive film (transparent electrode) from being lowered due to this.

Further, a conventional laminated type transparent conductive substrate having a transparent protective layer made of an inorganic oxide, an organic polymer or the like on a transparent conductive film (see the invention disclosed in the above-mentioned JP-A-61-16851). Except) is preferable in that this transparent protective layer can also function as a transparent electric insulating layer, but as described above, it is difficult to etch with an acid, so that it is easy to cause etching defects and the like. Have Therefore, it is difficult to obtain a transparent electrode (having a transparent electric insulating layer on the surface) capable of preventing the above-mentioned display failure by using this laminated transparent conductive substrate.

In the laminated transparent conductive substrate disclosed in the above-mentioned JP-A-61-16851, a protective layer (top coat layer) is formed by a coating method. The electric resistance value of the transparent conductive film is changed by ionic impurities present in the coating solution for forming the top coat layer), and the transparent conductive film is easily colored during driving, and the protective layer Since gel and foreign substances are inevitably present in the (top coat layer), the surface accuracy is relatively low, and when used as a transparent electrode of a liquid crystal display element, the cell gap of the liquid crystal cell is locally reduced. There is a drawback that it is easy to change and cause display unevenness.

An object of the present invention is a laminated transparent conductive substrate suitable for producing a transparent electrode having a transparent electrically insulating layer on the surface by an etching method, and having an electric resistance value of the transparent conductive film in the manufacturing process. To provide a laminated transparent conductive base material which can easily prevent the change of the above, can easily obtain a material having a relatively high surface accuracy, and has a high electric insulation property of the surface of the transparent electric insulation layer, and a method for producing the same. .

[0011]

A laminated transparent conductive substrate of the present invention which achieves the above object is formed by a transparent substrate and one main surface of the transparent substrate directly or through an undercoat layer. And a transparent electric insulating layer formed on the transparent conductive film, and the transparent electric insulating layer is made of an acid-soluble alkali-resistant inorganic compound. .

Further, the method for producing a laminated transparent conductive substrate of the present invention which achieves the above object is a physical vapor deposition method or a chemical vapor deposition method directly on one main surface of a transparent substrate or through an undercoat layer. A step of forming a transparent conductive film by a deposition method,
At least including a step of forming a transparent electric insulating layer made of an acid-soluble alkali-resistant inorganic compound on the transparent conductive film by a physical vapor deposition method or a chemical vapor deposition method, and
The oxygen partial pressure of the atmosphere in the step of forming the transparent electrically insulating layer has a relative oxygen content ratio of the transparent electrically insulating layer of 0.9 to
It is characterized in that it is controlled to fall within the range of 0.99.

The present invention will be described in detail below. First, the laminated transparent conductive substrate of the present invention will be described. This laminated transparent conductive substrate is, as described above, the transparent substrate and directly or through an undercoat layer on one main surface of this transparent substrate. At least the formed transparent conductive film and the transparent electrically insulating layer formed on the transparent conductive film are provided.

The transparent substrate is not particularly limited as long as it has desired transparency and electric insulation, and a transparent polymer film, a transparent polymer sheet, a transparent glass substrate or the like is used. be able to. Specific examples of the material of the transparent polymer film or the transparent polymer sheet include polycarbonate resin, polyarylate resin, polyether sulfone resin, amorphous polyolefin resin and the like. Specific examples of the material of the transparent glass substrate include soda-lime glass, white-plate glass, non-alkali glass, quartz glass and borosilicate glass.
The thickness of the transparent substrate is not particularly limited and is appropriately selected depending on the strength of the transparent substrate itself, the intended use of the laminated transparent conductive substrate, and the like.

The transparent conductive film provided on this transparent substrate directly or through the undercoat layer has indium (In) and zinc (Zn) as main cation elements.
A transparent conductive film made of an amorphous oxide containing
In atomic ratio In / (In + Zn) is 0.55 to 0.9
Those in the range of 0 are preferable. Here, the reason for limiting the atomic ratio In / (In + Zn) of In to the above range is that the conductivity of the film becomes low when the ratio is less than 0.55, and the etching property or wet heat resistance of the film decreases when the ratio exceeds 0.9. Because it does. A preferable range of the atomic ratio In / (In + Zn) of In is 0.65 to 0.90, and a particularly preferable range is 0.82 to 0.90.

The relative oxygen content ratio of the transparent conductive film made of the amorphous oxide is preferably 0.6 or more and less than 0.99. When the relative oxygen content ratio is out of this range, the conductivity and the light transmittance tend to be lowered, though it depends on the composition.
Here, the “relative oxygen content ratio” in the present specification is defined by the following equation.

[Equation 1] By using the above-mentioned amorphous oxide as the transparent conductive film, it becomes easy to obtain a laminated transparent conductive substrate having excellent conductivity, transparency, etching characteristics and resistance to moist heat.

The thickness of the transparent conductive film is preferably 100 to 10,000 angstroms. If it is less than 100 Å, it is difficult to obtain sufficient conductivity, and if it exceeds 10,000 Å, cracks and the like are likely to occur in the transparent conductive film when handling the obtained laminated transparent conductive substrate. A more preferable film thickness of the transparent conductive film is 300 to 7500 angstroms, and a particularly preferable film thickness is 500 to 6000 angstroms.

The above-mentioned transparent conductive film can be directly formed on one main surface of the above-mentioned transparent substrate, but if the adhesiveness between the transparent conductive film and the transparent substrate is low, an undercoat is formed. It is preferably formed through layers. This undercoat layer also needs to have desired transparency and electrical insulation, but its material is appropriately selected depending on what kind of material is used as the transparent substrate and the transparent conductive film. It Specific examples of the material of the undercoat layer include epoxy resin, polyphenoxy ether resin,
Acrylic resin, ethylene-vinyl alcohol copolymer,
One or more of organic compounds such as polyvinyl alcohol, polyacrylonitrile, polyvinylidene chloride and polyvinylidene fluoride, inorganic compounds such as SiO ₂ and TiO ₂ , or various silane coupling agents and various titanium coupling agents Can be mentioned. The film thickness of the undercoat layer is also not particularly limited, depending on the material of each of the transparent substrate and the transparent conductive film, the material of the undercoat layer itself, and the intended use of the laminated transparent conductive substrate. It is selected accordingly.

In the laminated transparent conductive substrate of the present invention, the transparent electrically insulating layer is provided directly on the transparent substrate or on the transparent conductive film described above formed via the undercoat layer. The transparent electrically insulating layer is made of an acid-soluble and alkali-resistant inorganic compound. Here, “acid-soluble-alkali resistance” means that the mask (resist film) used during etching is soluble in an acidic solution used as an etching solution for etching the transparent conductive film described above. It means that it is substantially insoluble in an alkaline solution for peeling.

The above-mentioned transparent electric insulation layer made of an acid-soluble and alkali-resistant inorganic compound is required to have desired transparency and electric insulation, and particularly, the electric insulation has a surface resistance of 1 or less. It is desired that it be × 10 ⁶ Ω / □ or more. When it is used as a material for two transparent electrodes (having a transparent electric insulation layer on the surface) constituting a liquid crystal display element with a small cell gap, if the surface resistance of the transparent electric insulation layer is less than 1 × 10 ⁶ Ω / □ When the two transparent electrodes come into local contact with each other directly or through the alignment film, a current may flow between these electrodes to cause display failure.

The acid-soluble and alkali-resistant inorganic compound suitable for obtaining such a transparent electrically insulating layer contains at least one selected from the group consisting of lanthanum oxide, silicon oxide and zinc oxide as a main component. Amorphous oxides, specifically, lanthanum oxide, silicon oxide, zinc oxide, silicon oxide-zinc oxide compounds, silicon oxide-lanthanum oxide compounds, zinc oxide-lanthanum oxide compounds, and the like, and the relative oxygen content ratios described above. Is an amorphous oxide having a range of 0.9 to 0.99. Those having a relative oxygen content ratio of more than 0.99 may not exhibit acid solubility-alkali resistance.
On the other hand, when the relative oxygen content ratio is less than 0.9, the surface resistance is less than 1 × 10 ⁶ Ω / □ or the light transmittance is too low (particularly in the case of lanthanum oxide).

When the transparent electric insulating layer is formed of the acid-soluble and alkali-resistant inorganic compound exemplified here, the film thickness is preferably 30 to 2000 angstroms. If it is less than 30 Å, it is difficult to obtain a sufficient electric insulation effect. On the other hand, if it exceeds 2000 angstrom, the manufacturing cost increases. At the same time, when a transparent electrode for a liquid crystal display device is produced from the obtained laminated transparent conductive substrate, the electric field strength acting on the liquid crystal display device is excessively lowered.

The laminated transparent conductive substrate of the present invention comprises at least the transparent substrate, the undercoat layer (arbitrary), the transparent conductive film, and the transparent electrically insulating layer composed of the acid-soluble and alkali-resistant inorganic compound described above. If you have. The thickness of the undercoat layer (arbitrary), the transparent conductive film, and the transparent electrically insulating layer composed of the acid-soluble and alkali-resistant inorganic compound provided on the transparent substrate is appropriately selected according to the intended use. However, it is generally within the range of 15 to 300 μm regardless of whether or not the undercoat layer is formed. In addition, the light transmittance in this state depends on the use and the like, but regardless of whether an undercoat layer is formed or not, all visible light or a wavelength of 550
It is preferably about 75% or more with respect to the light of nm. The light transmittance can be adjusted by appropriately selecting the thickness of each layer (film) and the material of each layer (film).

Further, the laminated transparent conductive substrate of the present invention comprises a gas barrier layer for improving environmental resistance and a transparent substrate on the surface of the transparent substrate opposite to the side where the transparent conductive film is formed. Further, it may have a hard coat layer for imparting scratch resistance and the like, an antireflection film for preventing surface reflection, and the like.
Whether or not to form such a layer or film is appropriately selected according to the intended use of the laminated transparent conductive substrate.

When the gas barrier layer is formed, a specific example thereof is a layer having a thickness of 0.1 to 10 μm, which is made of a polymer such as vinylidene chloride, vinylidene fluoride, acrylonitrile or the like and a copolymer with another monomer. Can be mentioned. When the hard coat layer is formed, specific examples thereof include titanium-based or silica-based hard coating agents, polymers such as polymethylmethacrylate, and inorganic polymers such as polyphosphazene having a thickness of 0.1 to 0.1. A layer of 10 μm can be mentioned. When the antireflection film is formed, specific examples thereof include low refractive index polymers, fluorides such as MgF ₂ and CaF ₂ , SiO ₂ , Bi ₂ O ₃ , and Al ₂ O _{3 having} a thickness of 100 to 100 nm. An example is a 1000 angstrom film.

The laminated transparent conductive substrate of the present invention can be basically manufactured by various methods. However, when a transparent polymer film or a transparent polymer sheet is used as the transparent substrate, since the heat resistance of the transparent substrate is relatively low, the transparent substrate is used to prevent thermal deformation and the like in the manufacturing process. Is preferably kept as low as possible, and it is necessary to form the transparent conductive film and the transparent electrically insulating layer having a desired composition under this substrate temperature. Also,
It is necessary to prevent changes in the electric resistance value of the transparent conductive film during the manufacturing process. From such a viewpoint, the laminated transparent conductive substrate of the present invention is preferably produced by the method of the present invention described in detail below.

As described above, the method of the present invention comprises a step of forming a transparent conductive film on one main surface of a transparent substrate directly or through an undercoat layer by a physical vapor deposition method or a chemical vapor deposition method. And a step of forming a transparent electrical insulating layer made of an acid-soluble and alkali-resistant inorganic compound on the transparent conductive film by a physical vapor deposition method or a chemical vapor deposition method, and the transparent electrical insulating layer The oxygen partial pressure of the atmosphere in the step of forming is controlled so that the relative oxygen content ratio of the transparent electric insulating layer is within the range of 0.9 to 0.99. . Here, specific examples of the physical vapor deposition method (PVD method) include a sputtering method, an EB evaporation (electron beam heating evaporation) method, an ion plating method, a vacuum evaporation method, and the like. Further, as a specific example of the chemical vapor deposition method (CVD method), plasma CVD or the like can be cited.

The conditions for forming the transparent conductive film are appropriately set depending on the film forming method, the composition of the target transparent conductive film, the type of raw materials used, etc., but at least the oxygen partial pressure of the atmosphere during film formation Is preferably controlled so that the relative oxygen content ratio of the obtained transparent conductive film is 0.6 or more and less than 0.99. When the relative oxygen content ratio of the transparent conductive film is out of this range, the conductivity and the light transmittance tend to be lowered, although it depends on the composition.

The conditions for forming the transparent electrically insulating layer are also set appropriately depending on the film forming method, the composition of the target transparent electrically insulating layer, the type of raw materials used, etc. The oxygen partial pressure is controlled so that the relative oxygen content ratio of the obtained transparent electric insulation layer is within the range of 0.9 to 0.99. This is because when the relative oxygen content ratio of the transparent electrically insulating layer exceeds 0.99, the acid-soluble-alkali resistance may not be exhibited, and when it is less than 0.9, the surface resistance is 1 × 10 ⁶ Ω. This is because it becomes less than / □ or the light transmittance is too low (particularly in the case of lanthanum oxide).

The film forming method used in the step of forming the transparent conductive film and the film forming method used in the step of forming the transparent electrically insulating layer may be the same or different, but in practice, they are the same. It is advantageous to form the transparent conductive film and the transparent electrically insulating layer by a film method. From the viewpoint of accurately and easily controlling the composition of the transparent conductive film and the transparent electrically insulating layer, the sputtering method is particularly preferable.

When the transparent conductive film or the transparent electrically insulating layer is formed by the sputtering method, the sputtering target is preferably an oxide or a metal depending on the composition of the target transparent conductive film or the transparent electrically insulating layer, and either single-source sputtering or multi-source sputtering is possible. But it's okay. The oxygen partial pressure in the sputtering atmosphere is appropriately set according to the composition of the sputtering target so that the relative oxygen content ratio of the target transparent conductive film or transparent electrically insulating layer becomes a desired value.

It is difficult to unconditionally define the sputtering conditions because they may largely depend on the characteristics of the apparatus used, but an example of the sputtering conditions in a commonly used DC magnetron sputtering apparatus is given below. For example, That is, the sputtering atmosphere is a mixed gas of an inert gas such as argon gas and oxygen gas, and the atmospheric pressure (total pressure) during sputtering is 1.3 × 10 ^{−2 to} 6.7 ×.
10 ⁰ Pa about, it is applied to the target voltage 50~500V
The substrate temperature is a temperature at which the transparent base material is not thermally deformed, and is cooled if necessary. In this case, the atmospheric pressure (total pressure) at the time of sputtering, that is, the degree of vacuum is 1.3 × 10 ^-2 Pa.
If less than 6.7, stability of plasma is poor and 6.7 × 10 ⁰ Pa
If it exceeds, it becomes difficult to increase the voltage applied to the target. If the target applied voltage exceeds 500V, a good quality film may not be formed, and if it is less than 50V, the film formation rate may be limited.

In the method of the present invention, the transparent conductive film and the transparent electrically insulating layer are formed as described above to obtain the above-mentioned laminated transparent conductive substrate of the present invention. In the transparent conductive substrate of the type, as described above, the undercoat layer is formed on the transparent substrate, if necessary. Further, a gas barrier layer, a hard coat layer, an antireflection film, etc. are formed on the surface of the transparent substrate opposite to the side on which the transparent conductive film is formed, if necessary. The formation of these optional constituent members is not particularly limited, but is preferably performed as follows. When a transparent polymer film or a transparent polymer sheet is used as the transparent substrate, it is preferable to form the transparent substrate while keeping the temperature of the transparent substrate as low as possible.

When the above-exemplified organic compounds, various silane coupling agents or various titanium coupling agents are used as the material of the undercoat layer, the undercoat layer is formed by a coating method, a spray coating method, a spin coating method or the like. Preferably. When using the above-exemplified inorganic compounds as the material of the undercoat layer,
The physical vapor deposition method (CVD method) or the chemical vapor deposition method (CVD method) described above is preferable, and the sputtering method (single or multiple) is particularly preferable. Further, the gas barrier layer, the hard coat layer and the antireflection film are also preferably formed by the same method as the above-mentioned method of forming the undercoat layer.

In the laminated transparent conductive substrate of the present invention which can be obtained by the method exemplified above, the transparent electrically insulating layer made of the acid-soluble and alkali-resistant inorganic compound is formed on the transparent conductive film as described above. The transparent conductive film and the transparent electrically insulating layer can be easily formed into a desired shape by one etching process. Even when the mask (resist film) used during etching is peeled off using an alkaline solution, the transparent conductive film is protected by the above-mentioned transparent electrically insulating layer, so that the transparent conductive film caused by contact with the alkaline solution. Deterioration of the electrical characteristics of is suppressed. For these reasons, the laminated transparent conductive substrate of the present invention is a substrate suitable for producing a transparent electrode (having an electrically insulating layer on the surface) by utilizing the etching method.

The transparent electrically insulating layer can be formed by a physical vapor deposition method or a chemical vapor deposition method. Therefore, by forming the transparent electrically insulating layer by these methods, the electrical resistance of the transparent conductive film in the manufacturing process is higher than that of a conventional laminated transparent conductive substrate in which a polymer thin film is formed on the transparent conductive film by a coating method. It is possible to easily prevent the value from changing.
At the same time, it is possible to easily obtain a material having higher surface accuracy than the conventional laminated transparent conductive substrate. Furthermore, the transparent electrically insulating layer formed on the transparent conductive film in the laminated transparent electrically conductive substrate of the present invention has high electrical insulation.

From these points, the laminated transparent conductive substrate of the present invention is a transparent electrode for a liquid crystal display device, particularly for a liquid crystal display device of a type in which the cell gap of a liquid crystal cell is small (having an electrically insulating layer on the surface thereof). ) Is suitable as a material for producing () by an etching method. Then, a transparent electrode (having an electric insulating layer on the surface) produced from the laminated transparent conductive substrate of the present invention is used as a transparent electrode of a liquid crystal display device of a type in which the cell gap of a liquid crystal cell is reduced (the electric insulating layer is formed on the surface). When the two electrodes constituting the element are locally contacted with each other, conduction at the contact location is suppressed, so that the responsiveness is high and the uselessness between the electrodes is high. It is possible to easily provide a liquid crystal display device in which display quality is less likely to decrease due to conduction. Further, the laminated transparent conductive substrate of the present invention is also suitable as a material for producing an electrically insulating layer and a transparent electrode for a double insulating structure inorganic EL display element in one etching step.

[0038]

EXAMPLES Examples of the present invention will be described below. Example 1 A polycarbonate film (having a thickness of 125
First, an undercoat layer made of epoxy resin and having a thickness of 5 μm was formed on the polycarbonate film. Further, after stacking polyvinylidene chloride on the surface of the polycarbonate film opposite to the surface on which the undercoat layer is formed using an adhesive, an epoxy acrylate resin prepolymer is coated on this polyvinylidene chloride, and the above-mentioned pre-coating is performed after coating. A gas barrier layer was formed by thermosetting the polymer. Next, the above-mentioned polycarbonate film provided with an undercoat layer was mounted on a DC magnetron sputtering apparatus, and the initial degree of vacuum in the vacuum chamber was set to 5 × 10 ⁻⁴ Pa, and then an oxide composed of indium oxide and zinc oxide. Sintered body target (In atomic ratio In
/(In+Zn)=0.67, sintered body density 90%, sputtering was carried out to form a transparent conductive film on the undercoat layer (hereinafter, this transparent conductive film was formed as a sample. That). The sputtering atmosphere at this time was a mixed atmosphere of 99.99% pure argon gas and oxygen gas, the total pressure of the sputtering atmosphere was 3 × 10 ⁻¹ Pa, and the ratio of the oxygen partial pressure to the total pressure was 0.3. %. Also, the sputtering condition is DC output 100.
W, sputtering time 40 minutes, substrate temperature room temperature.

The relative oxygen content ratio of the transparent conductive film thus formed was 0.74, and the film thickness was 2710 angstrom when measured by the stylus method using DEKTAK 3030 manufactured by Sloan. In addition, as a result of X-ray diffraction measurement (the model used is Rotaflex RU-200B manufactured by Rigaku Corporation), it was confirmed that this transparent conductive film was amorphous. Further, the atomic ratio In / (In + Zn) of In in this transparent conductive film was 0.70 as a result of ICP (inductively coupled plasma emission spectroscopy; the model used was SPS-1500VR manufactured by Seiko Instruments Inc.). The surface resistance (surface resistance of the transparent conductive film) of the above sample is 13Ω / □, and the light transmittance is 550 wavelengths.
It was 82.9% for the light of wavelength nm and 77.9% for the light of wavelength 400 nm.

Next, a transparent conductive film was formed except that this sample was mounted on a DC magnetron sputtering apparatus, SiO ₂ was used as a sputtering target, the oxygen partial pressure ratio was changed to 3%, and the sputtering time was changed to 5 minutes. Sputtering is performed in the same manner as above, and SiO ₂
Was formed on the transparent conductive film to a thickness of 250 Å. The relative oxygen content ratio of this transparent electrically insulating layer was 0.97. Further, when the crystallinity of this transparent electric insulating layer was examined by X-ray diffraction, it was confirmed to be amorphous. Furthermore, when the hardness of this transparent electric insulation layer was measured, the pencil hardness was 3H.
By forming the transparent electrically insulating layer on the polycarbonate film as described above, the intended laminated transparent conductive film was obtained.

The thus obtained laminated transparent conductive film has a surface resistance (surface resistance of the transparent electric insulating layer) of 1
It was as high as × 10 ⁶ Ω / □ or more. The light transmittance was 82.6% for light with a wavelength of 550 nm and 77.4% for light with a wavelength of 400 nm, indicating good transparency. Further, no deformation was observed in this laminated transparent conductive film, and it had a good appearance.

Regarding this laminated transparent conductive film, the etching rate with an acidic solution, the change in conductivity of the transparent conductive film due to the formation of the transparent electric insulating layer, the electric insulation of the transparent electric insulating layer, and the alkali resistance of the transparent electric insulating layer. , And flexibility were measured or evaluated as follows.

A. Etching rate with acidic solution A mixed solution of hydrochloric acid, nitric acid and water (hydrochloric acid: nitric acid: water = 1: 0.08: 1 (volume ratio)) was used as the acidic solution, and the transparent electrical insulating layer and the transparent conductive film were formed by the acidic solution. Was etched and the etching rate was measured.

B. Change in Conductivity of Transparent Conductive Film Due to Formation of Transparent Electrical Insulating Layer The transparent electrically insulating layers on both ends of the laminated transparent conductive film are etched with the same acidic solution as used in the above a to expose the transparent conductive film. After that, the electric resistance value between these both ends was measured. Then, by comparing this measured value with the electric resistance value of the transparent conductive film before forming the transparent electric insulating layer,
The presence or absence of change in conductivity of the transparent conductive film due to the formation of the transparent electrically insulating layer was examined.

C. Electrical Insulation of Transparent Electrical Insulation Layer Two laminated transparent conductive films described above are prepared.
Check the presence or absence of conduction in the state where the central portion of the surface of the transparent electrically insulating layer side of the laminated transparent conductive film of one sheet is in contact with each other,
From this result, the electric insulation of the transparent electric insulation layer was evaluated.
The contact at this time was performed under a load of 10 g / cm ² , and the measurement voltage was 20V.

D. Alkali resistance of transparent electric insulation layer Two laminated transparent conductive films were immersed in a 5 wt% sodium hydroxide aqueous solution for 5 minutes, and then the same procedure as in the above 2c was performed.
Check for electrical continuity between the laminated transparent conductive films,
From this result, the alkali resistance of the transparent electric insulation layer was evaluated.

E. Flexible laminated transparent conductive film 100
The electrical resistance value of the transparent conductive film after winding was measured in the same manner as in b above, and the flexibility of the laminated transparent conductive film was evaluated by comparing this measured value with the measured value before winding. . The results of a to e are shown in Table 1.

Example 2 After forming an undercoat layer and a gas barrier layer on a polycarbonate film in the same manner as in Example 1, an In ₂ O ₃ —ZnO-based sintered body (In atomic ratio In / ( In + Zn) = 0.85
A transparent conductive film was formed on the above-mentioned undercoat layer by performing sputtering under the same conditions as in Example 1 except that a sintered body density of 90% was used (hereinafter, this transparent conductive film was formed as a sample. That). The relative oxygen content ratio of the transparent conductive film thus formed was 0.75, and the film thickness was measured in the same manner as in Example 1 to be 2720 angstroms. In addition, as a result of X-ray diffraction measurement (using the same model as in Example 1), it was confirmed that this transparent conductive film was amorphous. Furthermore, I in this transparent conductive film
The atomic ratio In / (In + Zn) of n is I as in Example 1.
It was 0.88 as measured by CP analysis. The surface resistance (surface resistance of the transparent conductive film) of the above sample is 12 Ω / □, and the light transmittance is 550 nm.
Was 83.0% and the light having a wavelength of 400 nm was 78.1%.

Next, this sample was mounted on a DC magnetron sputtering apparatus and sputtered under the same conditions as in Example 1 to form a transparent electrically insulating layer of SiO _{2 having} a thickness of 250 Å on the transparent conductive film. . The relative oxygen content ratio of this transparent electrically insulating layer was 0.95.
Further, when the crystallinity of this transparent electric insulating layer was examined by X-ray diffraction, it was confirmed to be amorphous. further,
When the hardness of this transparent electric insulation layer was measured, the pencil hardness was 3H. By forming the transparent electrically insulating layer on the polycarbonate film as described above, the intended laminated transparent conductive film was obtained.

The laminated transparent conductive film thus obtained has a surface resistance (surface resistance of the transparent electric insulation layer) of 1
It was as high as × 10 ⁶ Ω / □ or more. The light transmittance was 82.7% for light with a wavelength of 550 nm and 77.7% for light with a wavelength of 400 nm, indicating good transparency. About this laminated type transparent conductive film, the etching rate with an acidic solution, the change in conductivity of the transparent conductive film due to the formation of the transparent electric insulating layer, the electric insulation of the transparent electric insulating layer, the alkali resistance of the transparent electric insulating layer, and the Flexibility was measured or evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 3 A glass substrate (# 705 manufactured by Corning Incorporated) was used as a transparent substrate.
9) was used to form a transparent conductive film on this glass substrate in the same manner as in Example 2 (hereinafter, this transparent conductive film is also called a sample). The relative oxygen content ratio of the transparent conductive film thus formed was 0.75, and the film thickness was measured in the same manner as in Example 1 to be 2720 angstroms. In addition, as a result of X-ray diffraction measurement (using the same model as in Example 1), it was confirmed that this transparent conductive film was amorphous. Furthermore, I in this transparent conductive film
The atomic ratio In / (In + Zn) of n is I as in Example 1.
It was 0.88 as measured by CP analysis. The surface resistance (surface resistance of the transparent conductive film) of the above sample is 12 Ω / □, and the light transmittance is 550 nm.
Was 83.2% and the light having a wavelength of 400 nm was 78.2%.

Next, this sample was mounted in a DC magnetron sputtering apparatus and sputtered under the same conditions as in Example 1 to form a transparent electrically insulating layer of SiO _{2 having} a thickness of 250 Å on the transparent conductive film. . The relative oxygen content ratio of this transparent electrically insulating layer was 0.95.
Further, when the crystallinity of this transparent electric insulating layer was examined by X-ray diffraction, it was confirmed to be amorphous. further,
When the hardness of this transparent electric insulation layer was measured, the pencil hardness was 3H. By forming the transparent electrically insulating layer on the glass substrate as described above, the intended laminated transparent conductive glass was obtained.

The laminated transparent conductive glass thus obtained has a surface resistance (surface resistance of the transparent electric insulation layer) of 1 ×.
It was as high as 10 ⁶ Ω / □ or more. In addition, the light transmittance is 82.8% for light having a wavelength of 550 nm, and the wavelength is 4
It was 77.8% for light of 00 nm, and had good transparency. About this laminated transparent conductive glass,
The etching rate by the acidic solution, the change in conductivity of the transparent conductive film due to the formation of the transparent electric insulating layer, the electric insulation of the transparent electric insulating layer, and the alkali resistance of the transparent electric insulating layer were measured in the same manner as in Example 1. evaluated. The results are shown in Table 1.

Example 4 An undercoat layer, a gas barrier layer and a transparent conductive film were formed on a polycarbonate film in the same manner as in Example 2 (hereinafter, this transparent conductive film is also called a sample). The relative oxygen content ratio of the transparent conductive film thus formed was 0.75, and the film thickness was measured in the same manner as in Example 1 to be 2720 angstroms. In addition, as a result of X-ray diffraction measurement (using the same model as in Example 1), it was confirmed that this transparent conductive film was amorphous. Further, the atomic ratio I of In in this transparent conductive film is I.
When n / (In + Zn) was measured by ICP analysis as in Example 1, it was 0.88. The surface resistance of the above sample (surface resistance of the transparent conductive film) is 12Ω /
□, and the light transmittance is 83.0% for light having a wavelength of 550 nm and 78.1% for light having a wavelength of 400 nm.
Met.

Next, this sample was mounted in a DC magnetron sputtering apparatus, and sputtering was carried out under the same conditions as in Example 2 except that a ZnO sintered body (sintered body density 80%) was used as a sputtering target to obtain ZnO. Was formed on the transparent conductive film to a thickness of 250 Å. The relative oxygen content ratio of this transparent electrically insulating layer was 0.96. The crystallinity of this transparent electrically insulating layer was examined by X-ray diffraction, and it was found to be amorphous. Furthermore, when the hardness of this transparent electric insulation layer was measured, the pencil hardness was 3H. By forming the transparent electrically insulating layer on the polycarbonate film as described above, the intended laminated transparent conductive film was obtained.

The laminated transparent conductive film thus obtained has a surface resistance (surface resistance of the transparent electric insulating layer) of 1
It was as high as × 10 ⁶ Ω / □ or more. The light transmittance was 82.8% for light with a wavelength of 550 nm and 77.8% for light with a wavelength of 400 nm, indicating good transparency. About this laminated type transparent conductive film, the etching rate with an acidic solution, the change in conductivity of the transparent conductive film due to the formation of the transparent electric insulating layer, the electric insulation of the transparent electric insulating layer, the alkali resistance of the transparent electric insulating layer, and the Flexibility was measured or evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 5 An undercoat layer, a gas barrier layer and a transparent conductive film were formed on a polycarbonate film in the same manner as in Example 2 (hereinafter, this transparent conductive film is also called a sample). The relative oxygen content ratio of the transparent conductive film thus formed was 0.75, and the film thickness was measured in the same manner as in Example 1 to be 2720 angstroms. In addition, as a result of X-ray diffraction measurement (using the same model as in Example 1), it was confirmed that this transparent conductive film was amorphous. Further, the atomic ratio I of In in this transparent conductive film is I.
When n / (In + Zn) was measured by ICP analysis as in Example 1, it was 0.88. The surface resistance of the above sample (surface resistance of the transparent conductive film) is 12Ω /
□, and the light transmittance is 83.0% for light having a wavelength of 550 nm and 78.1% for light having a wavelength of 400 nm.
Met.

Next, this sample was mounted in a DC magnetron sputtering apparatus, and sputtering was carried out under the same conditions as in Example 2 except that a lanthanum oxide sintered body (sintered body density 80%) was used as a sputtering target. A 250 Å thick transparent electrically insulating layer of lanthanum oxide was formed on the transparent conductive film. The relative oxygen content ratio of this transparent electrically insulating layer was 0.95. Further, when the crystallinity of this transparent electric insulating layer was examined by X-ray diffraction, it was confirmed to be amorphous. Furthermore, when the hardness of this transparent electric insulation layer was measured, the pencil hardness was 3H. By forming the transparent electrically insulating layer on the polycarbonate film as described above, the intended laminated transparent conductive film was obtained.

The laminated transparent conductive film thus obtained has a surface resistance (surface resistance of the transparent electric insulation layer) of 1
It was as high as × 10 ⁶ Ω / □ or more. The light transmittance was 82.8% for light with a wavelength of 550 nm and 77.8% for light with a wavelength of 400 nm, indicating good transparency. About this laminated type transparent conductive film, the etching rate with an acidic solution, the change in conductivity of the transparent conductive film due to the formation of the transparent electric insulating layer, the electric insulation of the transparent electric insulating layer, the alkali resistance of the transparent electric insulating layer, and the Flexibility was measured or evaluated in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1 After forming a transparent conductive film on a glass substrate by the sputtering method under the same conditions as in Example 1, the substrate temperature was set to 200 ° C.
RF using TiO ₂ as a sputtering target
A transparent electrically insulating layer was formed on the transparent conductive film by magnetron sputtering. When the crystallinity of this transparent electrically insulating layer was examined by X-ray diffraction, a peak based on TiO ₂ was observed. With respect to the laminated transparent conductive film thus obtained, the etching rate with an acidic solution was measured in Example 1.
It measured similarly to. The results are shown in Table 1.

[0061]

[Table 1]

As is clear from Table 1, in each of the laminated transparent conductive base materials (laminated transparent conductive film or laminated transparent conductive glass) of Examples 1 to 5, a transparent electrically insulating layer and a transparent conductive film were formed. Can be easily etched with an acidic solution, and the transparent electric insulating layer has excellent alkali resistance. Therefore, these laminated transparent conductive substrates are suitable as a material for producing a transparent electrode (having a transparent electrically insulating layer on the surface) by utilizing an etching method. Further, in each of the laminated transparent conductive substrates of Examples 1 to 5, since the pencil hardness of the transparent electrically insulating layer was as high as 3H,
When a transparent electrode (having a transparent electric insulation layer on the surface) is obtained by etching these laminated transparent conductive base materials, a transparent electrode having excellent abrasion resistance and abrasion resistance (Having an insulating layer) is obtained.

As is clear from Table 1, Example 1
In each of the laminated transparent conductive base materials of Example 5, the change in the conductivity of the transparent conductive film due to the formation of the transparent electrically insulating layer does not substantially occur. Furthermore, the transparent electrically insulating layer of each laminated transparent conductive substrate has a high surface resistance of 1 × 10 ⁶ Ω / □ or more, and its electrical insulating property is high. These Examples 1, 2,
Each of the laminated transparent conductive substrates 4 and 5 is also excellent in flexibility. On the other hand, the laminated transparent conductive substrate of Comparative Example 1 (laminated transparent conductive film) is difficult to etch with an acidic solution.

[0064]

As described above, in the laminated transparent conductive substrate of the present invention, the transparent electrically insulating layer and the transparent conductive film can be simultaneously and easily etched. In addition, this laminated transparent conductive substrate is easy to prevent the change of the electric resistance value of the transparent conductive film in the manufacturing process, it is easy to obtain a relatively high surface accuracy, and the surface electric insulation is high. Therefore, according to the present invention, a transparent electrode having a desired electric characteristic, which has a transparent electric insulating layer on the surface and can be used for a liquid crystal display element, an EL display element, or the like, can be easily manufactured by an etching method.

A transparent electrode (having a transparent electric insulating layer on the surface) prepared from the laminated transparent conductive substrate of the present invention is used as a transparent electrode (surface of a liquid crystal display element of a type in which the cell gap of a liquid crystal cell is reduced. When the two electrodes constituting the element are locally contacted with each other, conduction at the contact location is suppressed, so that the response is high and It is possible to easily provide a liquid crystal display device in which display quality is less likely to be reduced due to unnecessary conduction between the liquid crystal display devices.

Claims (10)

[Claims] 1. A transparent substrate, a transparent conductive film formed on one main surface of the transparent substrate directly or via an undercoat layer, and a transparent electrically insulating layer formed on the transparent conductive film. At least, and the transparent electrically insulating layer is made of an acid-soluble and alkali-resistant inorganic compound. 2. The acid-soluble and alkali-resistant inorganic compound is an amorphous oxide whose main component is at least one selected from the group consisting of lanthanum oxide, silicon oxide and zinc oxide, and The laminated transparent conductive substrate according to claim 1, wherein the relative oxygen content ratio in the product is in the range of 0.9 to 0.99. 3. The transparent conductive film is made of an amorphous oxide containing indium (In) and zinc (Zn) as main cation elements, and the atomic ratio I of In is I.
The laminated transparent conductive substrate according to claim 1 or 2, wherein n / (In + Zn) is within a range of 0.55 to 0.90. 4. The transparent conductive film is made of an amorphous oxide containing indium (In) and zinc (Zn) as main cation elements, and the atomic ratio I of In is I.
The laminated transparent conductive substrate according to claim 1 or 2, wherein n / (In + Zn) is in the range of 0.82 to 0.90. 5. The laminated transparent conductive substrate according to any one of claims 1 to 4, wherein the transparent substrate comprises a film-like or sheet-like transparent polymer. 6. The method according to claim 1, wherein the transparent substrate is made of glass.
The laminated transparent conductive substrate according to claim 4. 7. A step of forming a transparent conductive film on one main surface of a transparent substrate directly or through an undercoat layer by a physical vapor deposition method or a chemical vapor deposition method, and an acid on the transparent conductive film. At least including a step of forming a transparent electrically insulating layer made of a soluble-alkali resistant inorganic compound by a physical vapor deposition method or a chemical vapor deposition method, and oxygen in an atmosphere in the step of forming the transparent electrical insulating layer. The method for producing a laminated transparent conductive substrate, wherein the partial pressure is controlled so that the relative oxygen content ratio of the transparent electrically insulating layer is in the range of 0.9 to 0.99. 8. An amorphous oxide film according to claim 3 or 4 as a transparent conductive film is formed by a sputtering method, and then amorphous silicon oxide as a transparent electrically insulating layer is formed on the transparent conductive film. The method for producing a laminated transparent conductive substrate according to claim 7, wherein the film is formed by a sputtering method. 9. An amorphous lanthanum oxide film as a transparent electrically conductive layer is formed on the transparent conductive film after forming the amorphous oxide film according to claim 3 as a transparent conductive film by a sputtering method. Forming a film by a sputtering method,
The method for producing a laminated transparent conductive substrate according to claim 7. 10. The amorphous oxide film according to claim 3 or 4 as a transparent conductive film is formed by a sputtering method, and then amorphous zinc oxide as a transparent electric insulating layer is formed on the transparent conductive film. The method for producing a laminated transparent conductive substrate according to claim 7, wherein the film is formed by a sputtering method.