JPH0756179A - Production of transparent conductive film - Google Patents

Abstract

PURPOSE:To improve smoothness, optical isotropy and rightness of display by adding a leveling agent to a polyether sulfone(PES) soln. and forming a film by a casting method by using a substrate having a smooth surface. CONSTITUTION:A transparent conductive layer 10 is laminated on one surface of the film 9 formed by adding the leveling agent to the PES soln., applying the soln. on the substrate having <=0.05mum surface roughness and drying the coating, then peeling the film from the substrate and further a gas barrier layer 11 is laminated on at least one surface thereof. Commerctally marketed PES resins are usable as the PES. N, N-dimethyl formamicle, etc., are preferable as the solvent of the PES in the case of formation of the PES film by the casting method. The leveling agent includes leveling agents of a silicon system, such as, for example, polydimethyl siloxane, straight chain polymers such as polyalkyl acrylate, leveling agents of fluorine systems, such as fluorine surfactants and tetrafluoroethylene, hydrocarbon surfactants, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a transparent conductive film using a polyether sulfone (hereinafter referred to as PES) film as a substrate. More specifically, the present invention uses as a substrate a PES film having excellent transparency, optical isotropy and surface accuracy, which can be widely used in optoelectronics such as transparent electrodes for liquid crystal display devices and electrodes for electroluminescence, and electric fields. The present invention relates to a method for manufacturing a transparent conductive film.

[0002]

2. Description of the Related Art In recent years, liquid crystal display devices have been used in all fields, particularly in the electronic industry field such as word processors and personal computers. The liquid crystal display device has a structure as shown in FIG. 1, for example. In order to make the liquid crystal display device thin and lightweight, it is an important requirement that the transparent electrode for the liquid crystal display device, which is one component, be thin and lightweight.

Further, since the liquid crystal display device utilizes the optical anisotropy generated by the alignment of the liquid crystal, the substrate of the transparent conductive film is required to have a high degree of optical isotropy. Therefore, if a transparent electrode is made of a crystalline material, it will cause light scattering at the crystal part and refraction due to the orientation of molecules, so it is desirable to configure the transparent electrode with an amorphous material with excellent transparency. It is rare.

Further, even if the surface is fine, if it has irregularities, it causes partial scattering and refraction of light, which deteriorates transparency and optical isotropy, making it unsuitable for use as a substrate of a transparent conductive film. . Moreover, since the transparent conductive layer is a very thin film, if the surface is a little rough, the transparent conductive layer cannot be evenly provided, which may cause a partial difference in conductivity or disconnection. Must be smooth. Further, it is also required to have chemical resistance and heat resistance that are not affected by various chemicals used in complicated manufacturing processes. Moreover, since the liquid crystal element is easily deteriorated by oxygen, the transparent conductive film must have a high gas barrier property.

In Japanese Patent Laid-Open No. 59-137927, a glass plate having a polished surface is used as a substrate for a transparent electrode. Although a glass plate is non-crystalline and has a high gas barrier ability, it is inferior in flexibility and cannot meet the demands for thinning and mass production.

Therefore, a transparent conductive film substrate using a plastic film or sheet has been proposed. JP-A-60-260019 discloses a polycarbonate (hereinafter referred to as PC) film, a polysulfone (hereinafter referred to as PS) film, a polyethylene terephthalate (hereinafter referred to as PET) film, a polyether ether ketone (hereinafter referred to as PEEK). Film), P
Although a transparent conductive film using an ES film as a substrate is shown, the PC film has poor rigidity when the film thickness is thin,
PS film is not suitable because it lacks heat resistance.
Since the ET film and the PEEK film have optical anisotropy due to crystallization, they are not suitable for use as a substrate of a transparent conductive film for a liquid crystal display device which utilizes polarized light.

The PES film is an important film in the field of electronics because it has excellent heat resistance, mechanical properties, electrical properties, chemical resistance, transparency and is non-crystalline. However, the PES film is usually manufactured by the melt extrusion method, and the PES film having a high melting point and poor fluidity is processed under high temperature and high pressure conditions. Is bad. Therefore, irregular reflection of light and disorder of refraction are likely to occur, which adversely affects transparency and optical isotropy. Further, since the transparent conductive layer cannot be uniformly provided, disconnection is likely to occur, which limits its use in the field of precision electronics.

Due to the above-mentioned drawbacks, the PE method is used instead of the extrusion method.
Some attempts have been made to form a PES film by a method in which S is dissolved in an organic solvent is applied to a support, dried, and then peeled from the support (casting method).

Japanese Unexamined Patent Publication No. 60-138514 discloses PES.
The liquid crystal cover film (transparent conductive film substrate) by the casting film of the above is shown. But,
In the conventional casting method, the density of the surface layer and the surface tension become non-uniform with the evaporation of the solvent, and the surface is not smooth, and there are defects such as yuzu skin, which is a phenomenon that causes unevenness like yuzu skin. In addition, since the surface that is in close contact with the support also has fine irregularities, a sufficiently smooth film could not be obtained.

[0010]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a method for producing a transparent conductive film which is excellent in smoothness, optical isotropy and display clarity.

[0011]

DISCLOSURE OF THE INVENTION The inventors of the present invention have conducted extensive studies to obtain a clear and high-luminance image in a liquid crystal display device using a transparent conductive film, and as a result, form a PES film by the casting method. In the method, the roughness of the coating surface is reduced by adding an appropriate amount of a leveling agent to the PES solution, and the casting surface is smoothed by casting on a support having a surface roughness (Ra) of 0.05 μm or less. The inventors have found that the properties can be improved, and have found that they have a synergistic effect when they are carried out simultaneously, and completed the invention.

That is, according to the present invention, a leveling agent is added to a polyether sulfone solution to give a surface roughness (Ra) of 0.
A transparent conductive film characterized in that a transparent conductive layer is laminated on one surface of a film formed by peeling from the support after coating and drying on a support having a thickness of 05 μm or less, and further a gas barrier layer is laminated on at least one surface. Is a manufacturing method.

A commercially available PES resin can be used as the PES of the present invention. In the present invention, the solvent of PES used when forming a PES film by the casting method includes N, N-dimethylformamide (hereinafter, referred to as DMF), N, N-dimethylacetamide (hereinafter, DMA).
C), cyclohexanone (hereinafter referred to as CH),
N-methyl-2-pyrrolidone (hereinafter referred to as NMP),
Dichloromethyl, chloroform, tetrachloroethane,
An organic solvent in which PES can be dissolved, such as methylene chloride, can be used. Especially, from the viewpoint of solubility and boiling point of PES, DMF, D
MAC, CH, NMP are preferred. Further, although it does not directly dissolve PES, methyl ethyl ketone, toluene, acetone or the like may be used as a diluent.

The method of dissolving PES is not particularly limited, but for example, there is a method of adding PES powder to a solvent in a heated state while stirring. For smooth casting, it is preferable to degas bubbles generated when PES is dissolved. The ratio of PES to the solvent is not particularly limited, but solvent 1 may be used in terms of economy and ease of coating.
20 to 100 parts by weight is preferable with respect to 00 parts by weight.

Further, it is preferable to add an appropriate amount of a leveling agent to the PES solution. When the PES solution is applied as it is to the support, the viscosity changes during the drying process, which causes unevenness on the surface. Therefore, when a leveling agent having a function of lowering the surface tension is added and casting is performed, the flowability of the PES solution is improved, and unevenness on the surface can be prevented, so that a uniform coating film can be obtained.

Examples of the leveling agent to be used include silicon-based ones such as polydimethyl siloxane, methylphenyl siloxane and organic modified siloxanes, linear polymers such as polyalkyl acrylates and polyalkyl vinyl ethers, fluorine-based surfactants, tetra-functional surfactants. Examples thereof include fluorine-based ones such as fluoroethylene and hydrocarbon-based surfactants. Silicon type and fluorine type are particularly preferable because they do not affect the quality such as high leveling ability, transparency and optical isotropy, and have extremely excellent heat resistance.

The addition ratio of the leveling agent is 10% for the PES solution.
0.01 to 5 parts by weight is preferable with respect to 0 parts by weight. When the addition ratio of the leveling agent is in the above range, a film having a smooth surface and a transparent surface can be obtained due to the effect of the leveling agent. Addition ratio of leveling agent is 0.01
If less than the weight part, the effect of the leveling agent does not appear,
On the other hand, if the amount is more than 5 parts by weight, the PES solution does not flow evenly and is repelled, or the leveling agent floats on the surface after drying and scatters light. The method of adding the leveling agent to the PES solution is not particularly limited, but when adding a liquid leveling agent, a method of dropping the leveling agent while stirring the PES solution can be given as an example.

Further, various quality improving agents such as stabilizers and defoamers may be used within a range not impairing the properties such as surface smoothness, transparency and optical isotropy.

The support on which the PES solution is applied is a PET film, a PC film, a PEEK film, a polyimide (hereinafter referred to as PI) film, a polypropylene film or the like, has a smooth surface, heat resistance, and chemical resistance to the organic solvent used. Although any plastic film may be used, a PET film is particularly preferable in terms of heat resistance, surface smoothness, and economy.

The surface roughness (Ra) of the support is 0.0
It is preferably 5 μm or less. When the thickness is 0.05 μm or less, a PES film having a smooth surface suitable for use as a transparent conductive film for a liquid crystal display device can be obtained. If it exceeds 0.05 μm, the surface of the support cannot be said to be sufficiently smooth, and when the PES film is formed by the casting method, the irregularities of the support are transferred to the surface of the PES film that is in close contact with the support. , High surface roughness,
The PES film is not smooth. Therefore, light refraction and scattering occur on the surface of the film, which makes it unsuitable for use as a substrate of a transparent conductive film for a liquid crystal display device which requires transparency and optical isotropy.

Any coating method may be used as long as it can be uniformly cast, and examples thereof include known methods such as a die coating method, a Mayer bar coating method and a three-bar reverse method. It is preferable to filter the PES solution and apply the PES solution while removing insolubles and impurities in order to form a clean coating film.

Although the drying temperature depends on the heat resistant temperature of the support, it is preferably 70 ° C. or higher and 230 ° C. or lower, and more preferably 100 ° C. or higher and 200 ° C. or lower. If the temperature is lower than 70 ° C, the drying efficiency of the solvent is poor, and if the temperature is higher than 230 ° C, the surface condition is deteriorated due to bumping.

The drying time depends on the coating thickness and the drying temperature, but is preferably 5 minutes or more. If it is shorter than 5 minutes, the amount of residual solvent increases.

The thickness of the PES film is usually 5 μm or more and 500 μm or less, preferably 10 μm or more and 300 μm or less, and more preferably 25 μm or more and 100 μm or less. If the thickness is less than 5 μm, the mechanical strength is inferior.
If it is thicker than 00 μm, it is inferior in flexibility, and a great amount of time is required for drying, which is not practical.

The PES film used as the substrate of the transparent conductive film of the liquid crystal display device must have excellent transparency and optical isotropy. If the transparency and optical isotropy are excellent, the light incident on the PES film is transmitted straight and evenly, but if the surface has irregularities, there is a phenomenon in which the light is refracted in two directions (birefringence). Therefore, when used in a liquid crystal display device, the display will be double blurred and unclear,
The surface of the PES film should be smooth. PE
Regarding the optical isotropy of the S film, it is preferable that the retardation value (hereinafter referred to as R value) is 20 nm or less. . Here, the R value is a value indicating a phase shift of light due to birefringence, and the smaller the R value, the better the optical isotropy. R
If the value is larger than 20 nm, it becomes necessary to align the alignment axis of the deflector with the alignment axis of the substrate, which leads to poor workability. If the alignment axis is misaligned, the display becomes unclear and the proper viewing angle becomes narrow, resulting in a high quality transparent conductive film. Film cannot be obtained.

As the transparent conductive layer, a metal thin film of gold, silver, palladium or the like, indium tin oxide (hereinafter referred to as ITO), or a laminate of one or more selected from the group of tin oxide is used. .

As a method for forming the transparent conductive layer, known methods such as a spray method, a coating method and a vacuum treatment method can be used. Here, the vacuum treatment method is a method for forming a thin film of metal or the like under vacuum, and examples thereof include a vacuum vapor deposition method, a sputtering method, an ion plating method, an ion beam assisted vapor deposition method, and an ion cluster beam method. .

The thickness of the transparent conductive layer is 50 to 5,000.
Å is preferred. When the thickness is within the above range, the film has excellent transparency and conductivity. On the other hand, if the thickness is less than 50Å, the transparency is high, but the conductivity is poor, and
If it is thicker than 00Å, the conductivity is good, but the transparency is poor.

Since a liquid crystal element is deteriorated by oxygen, it is preferable to provide a gas barrier layer on the transparent conductive film.
As the gas barrier layer used in the present invention, PVDC,
PVA, ethylene-vinyl alcohol copolymer (hereinafter,
Examples thereof include an organic layer (referred to as EVOH) and an inorganic layer such as ITO and silicon oxide.

Among these, as a method for laminating the organic layer, in the case of laminating a liquid one, a coating method by a known method such as a die coating method, a Mayer bar coating method, a three-bar reverse method, or a film-shaped method is used. In the case of laminating, a known method such as a film dry laminating method may be used. Coating thickness is 1μ
m or more and 100 μm or less is preferable, and 5 μm or more and 60 μm
The following are more preferable. If it is less than 1 μm, the air resistance is poor, and if it is more than 100 μm, the flexibility is poor.

The inorganic layer is laminated in the same manner as the transparent conductive layer, preferably 50 Å or more and 5000 Å or less, and more preferably 100 Å or more and 1500 Å or less. Fifty
If it is thinner than Å, the air resistance is poor, and if it is thicker than 5000 Å, it is inferior in flexibility, and it may crack to deteriorate the air resistance.

The above-mentioned gas barrier layers may be used alone or in combination of two or more, and may be laminated on at least one surface of a transparent conductive film obtained by laminating a transparent conductive layer on a substrate.

As a layer for protecting the gas barrier layer,
An epoxy resin layer, an acrylic resin layer, a UV curable resin layer, etc. may be provided.

[0034]

EXAMPLES The present invention will be described in detail below with reference to examples. In addition, the measured value in an Example was based on the following method. Surface roughness (Ra) The surface roughness (Ra, unit: μm) was measured using Surfcom554A (manufactured by Tokyo Seimitsu Co., Ltd.), and the measurement length was 2.5 m.
m, and the cutoff value was 0.8 mm. R value (retardation value) Abbe's refractometer (manufactured by Atago Co., Ltd.) was used to measure the refractive index in the flow direction and width direction (direction perpendicular to the flow direction) using methylene iodide as an intermediate solution. Calculated by the formula. R value = d · | n ₁ −n ₂ | (unit: nm) d; Film thickness (nm) n ₁ ; Refractive index in flow direction n ₂ ; Refractive index in width direction Oxygen transmission rate OX-TRAN100 type Using a rate measuring device (manufactured by Modern Control Co., Ltd.), measurement was performed at a temperature of 23 ° C. and a relative humidity of 100%. The air permeability of the present invention is evaluated by this oxygen permeability.

Example 1 DMF (manufactured by Wako Pure Chemical Industries, Ltd.) 10 heated to 80 ° C.
PES powder (manufactured by BASF Corp.,
(Trade name: ULTRASON E2010) was dissolved while stirring 50 parts by weight. Further, with respect to 100 parts by weight of the PES solution, a silicon-based leveling agent (manufactured by Toray Dow Corning Silicone Co., Ltd., trade name: DC29PA) was used.
05 parts by weight of the PES solution was added dropwise with stirring. PET with a film thickness of 100 μm and surface roughness (Ra) of 0.04 μm
Film (manufactured by Unitika Ltd., trade name: Emblet)
The thickness of the PES solution after drying is 50 by the die coating method.
It was coated to a thickness of μm, dried at 180 ° C. for 20 minutes, and then peeled off from the PET film to obtain a PES casting film. The casting film had no die lines and no spots, had a smooth surface and good transparency.

Next, a transparent conductive layer consisting of three layers of ITO / silver / ITO is formed on one surface of the casting film D.
It was formed with a thickness of 1000 Å by C magnetron sputtering method. More specifically, the vacuum chamber is 1 × 1.
After evacuating to 0 ^-3 Torr, the pressure of argon gas is reduced to 3
Introduced up to × 10 ^-3 Torr and further total pressure is 4.5 × 1
An oxygen gas was introduced to 0 ⁻³ Torr, and an ITO layer having a thickness of 400 Å was formed on one surface of the PES casting film by a DC magnetron sputtering method using an indium tin alloy target. Then, a 200 Å silver layer was similarly formed on the ITO layer by using a metallic silver target at an argon gas pressure of 3 × 10 ^-3 Torr. Further, similarly to the first layer, an ITO layer was provided with a thickness of 400Å.

Next, PV is used as a gas barrier layer on the upper layer.
DC (Kureha Chemical Industry Co., Ltd., trade name: Kureharon latex) was applied by the Meyer bar coat method so that the thickness after drying would be 30 μm, and dried at 100 ° C. for 8 minutes to obtain a transparent conductive film. It was

The surface of the casting film that was in close contact with the support was used as the support surface, and the opposite surface was used as the coating surface, and the surface roughness (Ra), R value, and the transparent conductive film were used. We evaluated the oxygen transmission rate to see how much the sharpness of the display when the liquid crystal display device was actually assembled differed from the current product (using a glass plate). The evaluation results are shown in Table 1. The sharpness of the display was evaluated visually by three grades of ◯, Δ, and ×, where ◯ is a glass plate.

Example 2 A solvent for dissolving PES powder was mixed with 50 parts by weight of DMF in 50 parts by weight of toluene (manufactured by Wako Pure Chemical Industries, Ltd.), and the amount of the leveling agent added was 10 parts by weight of PES solution.
Example 1 except that 0.5 parts by weight was added to 0 parts by weight
A PES casting film was prepared in the same manner as in. The casting film had no die lines and no spots, had a smooth surface and good transparency. A transparent conductive layer was provided on the casting film in the same manner as in Example 1, and PVA (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name: Gohsenol) as a gas barrier layer was further formed thereon by the Mayer bar coating method to obtain a thickness after drying. Of 50 μm, and dried at 120 ° C. for 6 minutes to obtain a transparent conductive film. The casting film and the transparent conductive film were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

Example 3 The leveling agent used was a fluorine-based leveling agent (made by Asahi Glass Co., Ltd., trade name: Surflon), and the PES solution 10 was used.
A PES casting film was prepared in the same manner as in Example 1 except that 0.1 part by weight was added to 0 part by weight. The casting film had no die lines and no spots, had a smooth surface and good transparency.

Then, a transparent conductive layer was provided on one surface of the casting film in the same manner as in Example 1. Further, SiO ₂ as a gas barrier layer was further laminated thereon by an RF magnetron sputtering method using an SiO ₂ target at an argon gas pressure of 3 × 10 ⁻³ Torr to a thickness of 200 Å. The casting film and the transparent conductive film were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

Example 4 The leveling agent used was a fluorine-based leveling agent (manufactured by Mitsui DuPont Fluorochemical Co., Ltd., trade name: Teflon TL).
P), which is well dispersed in DMF.
A PES casting film was prepared in the same manner as in Example 1 except that 0.5 part by weight was added to 100 parts by weight of the solution. The casting film had no die lines and no spots, had a smooth surface and good transparency. Next, a transparent conductive layer was provided on one surface of the casting film in the same manner as in Example 1. Further, SiO ₂ as a gas barrier layer was further laminated thereon by an RF magnetron sputtering method using an SiO ₂ target at an argon gas pressure of 3 × 10 ⁻³ Torr to a thickness of 200 Å.
Furthermore, the thickness after drying was 2 as in Example 2 as the upper layer.
PVA was laminated so as to have a thickness of 0 μm. The casting film and the transparent conductive film were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

Example 5 The thickness of the PES casting film to be prepared is 10
A PES casting film was prepared in the same manner as in Example 1 except that the thickness was 0 μm. The casting film had no die line, the surface was smooth and the transparency was good. Next, a transparent conductive layer and a gas barrier layer were provided in the same manner as in Example 3 except that a SiO ₂ layer that was a gas barrier layer was provided on both surfaces of the casting film. The casting film and the transparent conductive film were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

Example 6 A support having a film thickness of 100 μm and a surface roughness (Ra) of 0.01
μm PI film (manufactured by Ube Industries, Ltd., trade name: UP
(ILEX), the drying temperature was 130 ° C., and the drying time was 1 hour, to prepare a PES casting film in the same manner as in Example 1. The casting film had no die line, the surface was smooth and the transparency was good. Next, a transparent conductive layer was provided on one surface of the casting film in the same manner as in Example 1. In addition, an ITO layer is used as a gas barrier layer on the opposite side of the transparent conductive layer at 400 Å
With the same thickness as the transparent conductive layer of Example 1.
The casting film and the transparent conductive film were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1 A PES film was prepared by melting and extruding a PES resin at 330 ° C. The extruded PES film had many streaks, die lines, and spots. Next, a transparent conductive layer and a gas barrier layer were provided on the extruded PES film in the same manner as in Example 1. The extrusion film and the transparent conductive film were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1. Regarding the display clarity, the display was particularly unclear when the liquid crystal display device was assembled with the orientation axes of the film and the deflection being at an angle of 45 ° C.

Comparative Example 2 A PES casting film was prepared in the same manner as in Example 1 except that the leveling agent was not added. The surface of the casting film had irregularities and was rough. Next, a transparent conductive layer and a gas barrier layer were provided on the casting film in the same manner as in Example 1. The casting film and the transparent conductive film were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.
Regarding the sharpness of the display, it was unclear because it felt muddy.

Comparative Example 3 A PES casting film was prepared in the same manner as in Example 1 except that 10 parts by weight of the leveling agent was added to 100 parts by weight of the PES solution. The casting film was a film in which the solution was repelled, and the dried leveling agent floated on the surface and the transparency and surface smoothness were poor. Next, a transparent conductive layer and a gas barrier layer were provided on the casting film in the same manner as in Example 1.
The casting film and the transparent conductive film were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1. Regarding the sharpness of the display, the display was distorted at the repelling portion and the portion with unevenness on the surface.

Comparative Example 4 A leveling agent was added to 0.00 parts by weight of PES solution in an amount of 0.00
PES as in Example 1 except that 1 part by weight was added.
I made a casting film. The casting film was a film in which the solution was repelled, and the dried leveling agent floated on the surface and the transparency and surface smoothness were poor. Next, a transparent conductive layer and a gas barrier layer were provided on the casting film in the same manner as in Example 1. The casting film and the transparent conductive film were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1. Regarding the sharpness of the display, it was unclear because it felt muddy.

Comparative Example 5 The support has a film thickness of 100 μm and a surface roughness (Ra) of 0.2 μm.
m PE film (trade name: Regulus, manufactured by Mitsui Toatsu Chemicals, Inc.)
I made a casting film. The casting film had fine irregularities on the surface, was not smooth, and had poor transparency. Next, a transparent conductive layer and a gas barrier layer were provided on one surface of the casting film in the same manner as in Example 1. The casting film and the transparent conductive film were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1. Regarding the sharpness of the display, it was blurry and unclear.

Comparative Example 6 A PES casting film and a transparent conductive film were obtained in the same manner as in Example 1 except that the gas barrier layer was not provided. The casting film and the transparent conductive film were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0051]

[Table 1] * 1: PES ratio 100 parts by weight of the solution, the unit parts * 2: ratio of PES to the unit cc / m ^2/24 hr or solvent: 5 to 100 parts by weight of the solvent
0 parts by weight

[0052]

According to the present invention, a PES film excellent in transparency and optical isotropy is obtained by adding a leveling agent to a PES solution and forming a film by a casting method using a support having a smooth surface. A highly reliable transparent conductive film that can be widely used in the field of electronics such as transparent electrodes for liquid crystal display devices, electrodes for electroluminescent bodies, electrodes for electrochromism, etc. Became.

[Brief description of drawings]

FIG. 1 shows an example of a liquid crystal display device.

FIG. 2 shows a PES casting film laminated with a transparent conductive layer and a gas barrier layer.

FIG. 3 shows a PES casting film provided with a transparent conductive layer, and a gas barrier layer laminated on both surfaces thereof.

[Explanation of symbols]

 1 Upper Polarizing Plate 2 Lower Polarizing Plate 3 Plastic Substrate 4 Transparent Conductive Film 5 Alignment Film 6 Reflector 7 Liquid Crystal 8 Seal 9 PES Casting Film 10 Transparent Conductive Layer 11 Gas Barrier Layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masaaki Yoshikai 2-1-1, Tango-dori, Minami-ku, Nagoya-shi, Aichi Mitsui Toatsu Chemicals, Inc. (72) Yoshihiro Sakai 2-chome, Tango-dori, Minami-ku, Nagoya, Aichi No. 1 Mitsui Toatsu Chemical Co., Ltd.

Claims (2)

[Claims] 1. A leveling agent is added to a polyether sulfone solution, coated on a support having a surface roughness (Ra) of 0.05 μm or less, dried, and then peeled from the support to form a film on one side. A method for producing a transparent conductive film, comprising laminating a transparent conductive layer, and further laminating a gas barrier layer on at least one surface. 2. The method for producing a transparent conductive film according to claim 1, wherein the amount of the leveling agent added is 0.01 to 5 parts by weight with respect to 100 parts by weight of the polyether sulfone solution.