WO2015118904A1 - Transparent conductive film - Google Patents

Abstract

The objective of the present invention is to provide a transparent conductive film which has good electrical conductivity and transparency and is capable of displaying beautiful images that are free from the occurrence of iridescent irregularities having angular dependence. A transparent conductive film according to the present invention comprises at least one transparent conductive layer and a high-refractive-index layer on a transparent resin supporting body. This transparent conductive film is characterized in that: the transparent resin supporting body has an in-plane retardation value (Ro) within the range of 0-150 nm at a measurement wavelength of 589 nm; the transparent conductive layer contains silver and has a thickness of 3-15 nm; and high-refractive-index layers are provided on both surfaces of the transparent conductive layer, and at least one of the high-refractive-index layers contains zinc sulfide.

Description

Transparent conductive film

The present invention relates to a transparent conductive film, and more particularly, to a transparent conductive film having good conductivity and transparency and capable of displaying beautiful images without generating rainbow unevenness having angle dependency.

In recent years, transparent conductive films have been used in various devices such as liquid crystal displays, plasma displays, inorganic and organic EL (electroluminescence) displays, touch panels, and solar cells.

As a material constituting such a transparent conductive film, metals such as gold, silver, platinum, copper, rhodium, palladium, aluminum, and chromium, In ₂ O ₃ , CdO, CdIn ₂ O ₄ , Cd ₂ SnO ₄ , and TiO _{2 are used.} , SnO ₂ , ZnO, ITO (indium tin oxide) and other oxide semiconductors are known.

Here, in a touch panel type display device or the like, a transparent conductive film made of a transparent conductive film or the like is disposed on the image display surface of the display element. Therefore, the transparent conductive film is required to have high light transmittance. In such various display devices, a transparent conductive film made of ITO having high light transmittance is often used.

In recent years, a capacitive touch panel display device has been developed, and it is required to further reduce the surface electrical resistance of the transparent conductive film. However, the conventional ITO film has a problem that the surface electric resistance cannot be sufficiently lowered.

Thus, it has been studied to use a silver deposited film as a transparent conductive film (see, for example, Patent Document 1). Further, in order to increase the light transmittance of the transparent conductor, a silver deposited film is formed of a film having a high refractive index (for example, niobium oxide (Nb ₂ O ₅ ), IZO (indium / zinc oxide), ICO (indium / cerium oxide). ), And a-GIO (a film made of gallium, indium, and oxygen) are also proposed (see, for example, Patent Documents 2 to 4). Further, it has been proposed to sandwich a vapor deposited silver film with a zinc sulfide film (see, for example, Non-Patent Documents 1 and 2).

On the other hand, information devices equipped with touch panels in recent years have been required to achieve higher image quality, operational accuracy, and response speed at the same time as demands for larger screens, lighter weights and thinners. The importance of transparency is increasing more than ever, and it is important not to degrade the original display image because of the characteristics required from the viewpoint of the image display function. However, as the touch panel device increases in screen size, the user has to view the video at a wider angle. As a result, when the display device is viewed from an oblique direction, a rainbow-like unevenness occurs on the screen. The occurrence of the phenomenon became an important issue. When a metal was used as the material for forming the transparent conductive film to form a thin film, rainbow unevenness with angle dependency occurred.

Special table 2011-508400 gazette JP 2006-184849 A JP 2002-15623 A JP 2008-226581 A

An object of the present invention is to provide a transparent conductive film having good conductivity and transparency, and capable of beautiful image display without occurrence of rainbow unevenness having angle dependency.

In order to solve the above-mentioned problems, the present inventor uses a transparent resin support having a small in-plane retardation value Ro for the transparent conductive film in the process of examining the cause of the above-mentioned problems, and contains silver thereon. By providing a high refractive index layer on both sides of the transparent conductive layer and the transparent conductive layer, and further including zinc sulfide in at least one high refractive index layer, rainbow unevenness having good conductivity and angle dependency does not occur. The present inventors have found that a transparent conductive film capable of displaying beautiful images can be obtained, and have reached the present invention.

That is, the above-mentioned problem according to the present invention is solved by the following means.

1. A transparent conductive film having at least one transparent conductive layer and a high refractive index layer on a transparent resin support,
The in-plane retardation value Ro of the transparent resin support at a measurement wavelength of 589 nm is in the range of 0 to 150 nm,
The transparent conductive layer contains silver and has a layer thickness in the range of 3 to 15 nm;
The transparent conductive film, wherein the high refractive index layer is provided on both sides of the transparent conductive layer, and at least one high refractive index layer contains zinc sulfide.

2. 2. The transparent conductive film according to item 1, wherein a retardation value Rt in the thickness direction at a measurement wavelength of 589 nm of the transparent resin support is within a range of 0 to 400 nm.

3. The transparent conductive film according to Item 1 or 2, wherein the transparent resin support contains at least one selected from cellulose ester resins, cycloolefin resins, and polycarbonate resins.

4. The transparent conductive layer contains at least one metal selected from gold, copper, nickel, palladium, platinum, zinc, aluminum, manganese, germanium, bismuth, neodymium, and molybdenum. 4. The transparent conductive film according to any one of items up to 3.

5. Of the high refractive index layers provided on both sides of the transparent conductive layer, the high refractive index layer on the support side contains zinc sulfide. The transparent conductive film as described.

6. Among the high refractive index layers provided on both sides of the transparent conductive layer, the high refractive index layer provided on the side opposite to the support side is composed of indium tin oxide, indium zinc oxide, gallium zinc oxide. Or any one of indium, gallium, and zinc oxide, The transparent conductive film according to any one of Items 1 to 5,

7. The transparent conductive material according to any one of Items 1 to 6, further comprising a layer containing zinc oxide between the transparent conductive layer and the at least one high refractive index layer. the film.

By the above means of the present invention, it is possible to provide a transparent conductive film having good conductivity and transparency and capable of displaying beautiful images without generating rainbow unevenness having angle dependency.

The expression mechanism or action mechanism of the effect of the present invention is not clear, but is presumed as follows.

The transparent conductive film of the present invention is a transparent conductive film having at least one transparent conductive layer and a high refractive index layer on a transparent resin support, and the in-plane retardation Ro of the transparent resin support is 0 to 150 nm. By making it within the range, it is possible to prevent rainbow unevenness having angle dependency.

General rainbow unevenness means that in a display image of a transmissive capacitive touch panel, part or all of the members constituting the transparent conductive film have a large retardation value, so that image light having a certain polarization state is generated. This is caused by being converted into a different polarization state for each wavelength and viewing angle when passing through the stacked members of the touch module.

FIG. 1 is a schematic diagram for explaining a general rainbow unevenness generation mechanism. A typical configuration of an out-cell type transmissive capacitive touch panel is simplified and schematically shown by focusing on a change in the polarization state of light rays. Showed. Therefore, it does not faithfully reproduce the actual product form and light rays.

In FIG. 1, reference numeral 300 represents an image display element such as a liquid crystal, and a polarizing plate 200 is provided on the outermost surface thereof. Furthermore, the transparent conductive film 100 exists in the upper part.

Here, the light emitted from the different pixels A and B travels along the different optical paths in the transparent conductive film as linearly polarized light by the action of the polarizing plate. At this time, since the support of the transparent conductive film has retardation, each light beam traveling in different optical paths is converted into a different polarization state before passing through A ₁ and B _1, and then the observer's Reach viewpoint O.

At this time, interface reflection occurs at the viewing-side interface of the transparent conductive film 100, but according to Fresnel's equation, the reflectance at this time differs for each polarization component of the light beam, and the incident angle is φ ₁ and the refraction angle is φ. ₂ (in FIG. 1, φ _A1 represents an incident angle from point A, φ _A2 represents a refraction angle from point A. Similarly, φ _B1 represents an incident angle from point B, φ _B2 represents the refraction angle from point B),
The p-polarized light Rp is
Rp = {tan (φ ₁ −φ ₂ )} / {tan (φ ₁ + φ ₂ )}
S-polarized light Rs is
Rs = − {sin (φ ₁ −φ ₂ )} / {sin (φ ₁ + φ ₂ )}
It is represented by

As is clear from the above equation, the s-polarized component shows a high reflectivity with respect to the p-polarized component, but as a result, the intensity of the transmitted light is naturally greater for p-polarized light than for s-polarized light, and the ratio is angularly dependent. You can see that

On the other hand, as described above, since the light beams emitted from the pixels A and B in FIG. 1 have different polarization states, the amplitude ratios of the p-polarized light component and the s-polarized light component are not already the same.

Therefore, the intensities of the two light beams transmitted from A ₁ and B ₁ to the viewer side are different, and the viewer visually recognizes the contrast as bright and dark for each part. In addition, since the refractive index varies depending on the wavelength, the reflection intensity ratio for each of the p-s polarization components also varies depending on the wavelength, and the resulting contrast level differs depending on the color.

This is the general principle of rainbow unevenness, and it is a very important problem in the trend toward larger screens of video display devices equipped with touch panels in recent years.

In a conventional touch panel, a material having a large refractive index such as ITO was used as a transparent conductive film, and general rainbow unevenness was strongly generated. Therefore, in the case of a material having a refractive index smaller than ITO, such as silver, Although it was predicted that the reflection at the interface would be reduced and its generation would be suppressed, contrary to expectation, rainbow unevenness with angle dependency occurred. It is speculated that the absorption of the transparent conductive layer containing silver and the thinness of the layer may be caused.

As described above, the inventors of the present invention provide a video display device including a touch panel having a large screen and excellent visibility based on excellent transparent conductivity. However, in the form actually provided, since the user views the image with a larger viewing angle than before, the angle-dependent color unevenness is conspicuous on the contrary. I found it to be a serious problem.

At the same time, the present inventors have found out that the angle-dependent color unevenness can be solved under a limited and densely configured condition. That is, by using a support with low retardation and skillfully combining a high refractive index layer and an antisulfuration layer described later with a conductive layer containing silver, industrial practicality and excellent conductivity can be obtained. A transparent conductive film that simultaneously realizes transparency and beautiful image display can be obtained.

Schematic diagram explaining the rainbow unevenness generation mechanism Schematic sectional view showing an example of the layer structure of the transparent conductive film of the present invention The schematic diagram which shows an example of the pattern which consists of a conduction | electrical_connection area | region and an insulation area | region of the transparent conductive film of this invention. The schematic diagram which shows an example of the electrode pattern which consists of a conduction | electrical_connection area | region and an insulation area | region of the transparent conductive film of this invention. Process flow diagram showing an example of forming an electrode pattern on the transparent conductor of the present invention by photolithography Process flow diagram showing an example of forming an electrode pattern on the transparent conductor of the present invention by photolithography Process flow diagram showing an example of forming an electrode pattern on the transparent conductor of the present invention by photolithography Process flow diagram showing an example of forming an electrode pattern on the transparent conductor of the present invention by photolithography Process flow diagram showing an example of forming an electrode pattern on the transparent conductor of the present invention by photolithography Process flow diagram showing an example of forming an electrode pattern on the transparent conductor of the present invention by photolithography Process flow diagram showing an example of forming an electrode pattern on the transparent conductor of the present invention by photolithography

The transparent conductive film of the present invention is a transparent conductive film having at least one transparent conductive layer and a high refractive index layer on a transparent resin support,
The in-plane retardation value Ro of the transparent resin support at a measurement wavelength of 589 nm is in the range of 0 to 150 nm,
The transparent conductive layer contains silver and has a layer thickness in the range of 3 to 15 nm;
The high refractive index layer is provided on both sides of the transparent conductive layer, and at least one high refractive index layer contains zinc sulfide. This feature is a technical feature common to the inventions according to claims 1 to 7.

As an embodiment of the present invention, it is preferable that the thickness direction retardation value Rt of the transparent resin support is in the range of 0 to 400 nm from the viewpoint of manifesting the effects of the present invention.

Further, when the transparent resin support contains at least one selected from a cellulose ester resin, a cycloolefin resin and a polycarbonate resin, the in-plane retardation value Ro can be within the above range, and the angle dependency This is preferable because an effect of preventing rainbow unevenness can be obtained.

It is preferable that the transparent conductive layer contains at least one metal selected from gold, copper, nickel, palladium, platinum, zinc, aluminum, manganese, germanium, bismuth, neodymium and molybdenum.

Of the high refractive index layers provided on both sides of the transparent conductive layer, the high refractive index layer on the support side preferably contains zinc sulfide.

Among the high refractive index layers provided on both sides of the transparent conductive layer, the high refractive index layer provided on the side opposite to the support side is composed of indium tin oxide, indium zinc oxide, gallium zinc It is preferable to contain either an oxide or indium / gallium / zinc oxide.

Moreover, it is preferable to have a layer containing zinc oxide between the transparent conductive layer and the at least one high refractive index layer.

Hereinafter, constituent elements of the present invention, and modes and modes for carrying out the present invention will be described in detail. In the present application, “˜” is used to mean that the numerical values described before and after it are included as a lower limit and an upper limit.

≪Transparent conductive film≫
One embodiment of the layer structure of the transparent conductive film of the present invention is shown in FIGS.

The transparent conductive film 100 of the present invention includes transparent resin support 1 / first high refractive index layer 2 / transparent conductive layer 3 / second high refractive index layer 4. In the transparent conductive film 100 of the present invention, one of the first high refractive index layer 2 and the second high refractive index layer 4 is a layer containing zinc sulfide (ZnS). Furthermore, it is preferable to have an antisulfurization layer 5a or 5b containing at least one layer of zinc oxide between the first and second high refractive index layers 2 and 4 and the transparent conductive layer 3. Moreover, these layers are layers formed from a thin film.

In FIG. 2, one of the first high refractive index layer 2 and the second high refractive index layer 4 is a layer containing zinc sulfide, and the first high refractive index layer 2 or the second high refractive index layer. 4 and the transparent conductive layer 3 are preferably provided with an anti-sulfurization layer 5 (an anti-sulfurization layer 5a or 5b containing zinc oxide).

When the transparent conductive layer and the high refractive index layer containing zinc sulfide are formed adjacent to each other, there is a problem that metal sulfide is easily generated and the light transmittance of the transparent conductive film is likely to be lowered. The metal sulfide is presumed to be produced as follows.

When a transparent conductive layer is formed on the first high refractive index layer 2 (zinc sulfide-containing layer) by a vapor deposition method such as sputtering, the unreacted sulfur component in the first high refractive index layer 2 is transparent. It is blown out into the film forming atmosphere by the metal material (silver) of the conductive layer. Then, the released sulfur component reacts with silver, and silver sulfide is deposited on the high refractive index layer. Moreover, when forming a high refractive index layer and a transparent conductive layer continuously, the sulfur component contained in the film-forming atmosphere of a high refractive index layer remains in the metal layer atmosphere containing the silver of a transparent conductive layer. Then, the sulfur component and silver react to deposit silver sulfide on the high refractive index layer.

On the other hand, when the second high refractive index layer (zinc sulfide-containing layer) is formed on the transparent conductive layer, the silver in the metal film containing silver of the transparent conductive layer is formed by the material of the second high refractive index layer. Played in the film atmosphere. Then, the ejected silver reacts with the sulfur component, and silver sulfide is deposited on the surface of the transparent conductive layer. Furthermore, silver sulfide is generated on the surface of the metal layer containing silver of the transparent conductive layer even when the surface of the transparent conductive layer is in contact with the sulfur component in the film forming atmosphere.

On the other hand, in the transparent conductive film 100 of the present invention, for example, as shown in FIG. 2, the first sulfidation preventing layer 5 a containing zinc oxide may be laminated on the first high refractive index layer 2. . In this configuration, since the first high refractive index layer 2 is protected by the first antisulfurization layer 5a, it is difficult for the sulfur component in the first high refractive index layer 2 to be ejected when the transparent conductive layer 3 is formed. Even if the first high-refractive index layer 2 and the conductive layer 3 are continuously formed, the sulfur component contained in the film formation atmosphere of the first high-refractive index layer 2 is a component of the first antisulfurization layer 5a. Or adsorbed to the constituent components of the first sulfurization prevention layer 5a. Therefore, it becomes difficult for sulfur to be contained in the film-forming atmosphere of the transparent conductive layer 3, and the production of silver sulfide is suppressed.

Moreover, in the transparent conductive film 100 of the present invention, for example, as shown in FIG. 2, the second sulfidation preventing layer 5 b may be laminated on the transparent conductive layer 3. In this configuration, since the transparent conductive layer 3 is protected by the second sulfidation preventing layer 5b, silver in the transparent conductive layer 3 is hardly ejected when the second high refractive index layer 4 is formed. Further, the sulfur component in the film formation atmosphere of the second high refractive index layer 4 is difficult to come into contact with the surface of the transparent conductive layer 3. Therefore, it is difficult to produce silver sulfide on the surface of the transparent conductive layer 3.

In the transparent conductive film of the present invention, as shown in FIG. 2, the transparent conductive layer 3 may be laminated on the entire surface of the transparent resin support 1, and as shown in FIG. It may be patterned into a desired shape. In the transparent conductive film of the present invention, the region a where the transparent conductive layer 3 is laminated is a region where electricity is conducted (hereinafter also referred to as “conduction region”). On the other hand, as shown in FIG. 3, the region b not including the transparent conductive layer 3 is an insulating region.

The pattern composed of the conductive region a and the insulating region b is appropriately selected according to the use of the transparent conductive film 100. For example, when the transparent conductive film 100 is applied to an electrostatic touch panel, as shown in FIG. 4, the pattern includes a plurality of conductive regions a and line-shaped insulating regions b that divide the conductive regions a. It is possible.

In addition, the transparent conductive film 100 of the present invention includes layers other than the transparent resin support 1, the first high refractive index layer 2, the transparent conductive layer 3, the second high refractive index layer 4, and the sulfurization prevention layer 5. May be included. For example, an underlayer that can be a growth nucleus when forming the transparent conductive layer 3 may be included between the transparent conductive layer and the first high refractive index layer 2 adjacent to the transparent conductive layer 3.

≪About layer structure of transparent conductive film≫
<1. Transparent resin support>
Examples of the transparent resin support 1 used for the transparent conductive film 100 include cellulose ester resins (for example, triacetylcellulose (Zerotac (manufactured by Konica Minolta)), diacetylcellulose, acetylpropionylcellulose, etc.), polycarbonate resins (for example, panlite, Multilon (both made by Teijin)), cycloolefin resin (for example, Zeonoa (made by Nippon Zeon), Arton (made by JSR), Apel (made by Mitsui Chemicals)), acrylic resin (for example, polymethyl methacrylate, acrylite ( (Mitsubishi Rayon Co., Ltd.) and Sumipex (Sumitomo Chemical Co., Ltd.)), and these resins are preferably 50% by mass or more of the transparent resin support. Two or more kinds of these resins may be used.

Of these resins, cellulose ester resins, cycloolefin resins, and polycarbonate resins are preferable.

Other resins that may be mixed include polyimide, phenol resin, epoxy resin, polyphenylene ether (PPE) resin, polyester resin (for example, polyethylene terephthalate (PET), polyethylene naphthalate), polyether sulfone, ABS / AS resin, One or more resins selected from MBS resin, polystyrene, methacrylic resin, polyvinyl alcohol / EVOH (ethylene vinyl alcohol resin), styrene block copolymer resin, and the like may be included.

Further, when the transparent resin support 1 used in the present invention is a cellulose ester, a lower fatty acid ester is preferable, and cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate propionate butyrate, or the like is used. Preferably used. The cellulose ester used in the present invention preferably has an acyl group substitution degree of 2.85 to 3.00 because the degree of plane orientation can be kept lower, and particularly preferably 2.92 to 3.00.

The method for measuring the substitution degree of the acyl group can be measured in accordance with the provisions of ASTM-D817-96.

A cellulose ester having a polymerization degree of 250 to 400 is preferably used, and cellulose triacetate is particularly preferably used. The number average molecular weight Mn of the cellulose ester according to the present invention is preferably 70000 to 250,000, since it is excellent in mechanical strength and has an appropriate dope viscosity, and more preferably 80000 to 150,000. A cellulose ester having a ratio Mw / Mn to the weight average molecular weight Mw of 1.0 to 5.0 is preferably used.

The in-plane retardation value Ro of the transparent resin support of the present invention at a measurement wavelength of 589 nm is in the range of 0 to 150 nm. Preferably, Ro is in the range of 0 to 20 nm or 40 to 150 nm.

The thickness direction retardation value Rt at a measurement wavelength of 589 nm is preferably in the range of 0 to 400 nm, and particularly preferably, Rt is in the range of 0 to 70 nm or Rt is in the range of 80 to 300 nm. By setting Rt to a preferred range, the visibility when wearing sunglasses using a polarizing plate is improved.

Formula (i) Ro = (nx−ny) × d
Formula (ii) Rt = ((nx + ny) / 2−nz) × d
(In the formula, Ro is the retardation value in the film plane, Rt is the retardation value in the thickness direction, nx is the refractive index in the slow axis direction in the film plane, ny is the refractive index in the fast axis direction in the film plane, (nz represents the refractive index in the thickness direction of the film, and d represents the thickness (nm) of the film.)
In the present invention, the in-plane retardation value Ro and the thickness direction retardation value Rt at a measurement wavelength of 589 nm are measured with a phase difference measuring device “KOBRA-21ADH” (Oji Scientific Instruments) in an environment of 23 ° C. and 55% RH. Measured by).

The retardation value of the transparent resin support can be controlled by selecting the resin material, the draw ratio during film formation, and the like. Specifically, it can be controlled to an arbitrary value by appropriately selecting the stretching ratio in the longitudinal direction and the transverse direction.

The transparent resin support 1 of the present invention preferably has high transparency to visible light, and the average transmittance of light having a wavelength of 450 to 800 nm is preferably 70% or more, more preferably 80% or more. And more preferably 85% or more. When the average light transmittance of the transparent resin support 1 is 70% or more, the light transmittance of the transparent conductive film 100 is likely to increase. Further, the average absorptance of light having a wavelength of 450 to 800 nm of the transparent resin support 1 is preferably 10% or less, more preferably 5% or less, and further preferably 3% or less.

The average transmittance is measured by making light incident from an angle inclined by 5 ° with respect to the normal line of the surface of the transparent resin support 1. On the other hand, the average absorptance is measured by measuring the average reflectance of the transparent substrate 1 by making light incident from the same angle as the average transmittance.
Average absorptance (%) = 100− (average transmittance + average reflectance)
Calculate as Average transmittance and average reflectance are measured with a spectrophotometer.

In order to make the transmittance of the transparent resin support within the above range, the surface roughness Ra of the transparent resin support is preferably 3.5 nm or less on both surfaces of the transparent resin support, more preferably. Is 3.0 nm or less. When the surface roughness Ra of the transparent resin support is 3.5 nm or less on both surfaces of the transparent resin support, the haze value is reduced and a transparent resin support excellent in transparency can be obtained. Here, the surface roughness Ra refers to the arithmetic average roughness in JIS B0601: 2001.

The haze value of the transparent resin support 1 of the present invention is preferably 0.01 to 2.5, more preferably 0.1 to 1.2. The haze value of a transparent conductive film is suppressed as the haze value of a support body is 2.5 or less. The haze value is measured with a haze meter “model: NDH 2000” (manufactured by Nippon Denshoku Co., Ltd.).

The refractive index of light having a wavelength of 570 nm of the transparent resin support 1 is preferably 1.40 to 1.95, more preferably 1.45 to 1.75, and still more preferably 1.45 to 1.70. It is. The refractive index of the transparent resin support is usually determined by the material of the support. The refractive index of the transparent resin support is measured with an ellipsometer at 23 ° C. and 55% RH.

The thickness of the transparent resin support 1 is preferably 1 μm to 20 mm, more preferably 10 μm to 2 mm. When the thickness of the transparent resin support is 1 μm or more, the strength of the transparent resin support 1 is increased, and the first high refractive index layer 2 is difficult to be cracked or torn. On the other hand, if the thickness of the transparent resin support 1 is 20 mm or less, the flexibility of the transparent conductive film 100 is sufficient. Furthermore, the thickness of the apparatus using the transparent conductive film 100 can be reduced. Moreover, the apparatus using the transparent conductive film 100 can also be reduced in weight.

<2. First High Refractive Index Layer>
The high refractive index layer in the present invention refers to a layer having a higher refractive index than that of the transparent resin support 1.

The first high refractive index layer 2 is a layer that adjusts the light transmission (optical admittance) of the conductive region a of the transparent conductive film, that is, the region where the transparent conductive layer 3 is formed, and at least the transparent conductive film 100. Formed in the conductive region a. The first high-refractive index layer 2 has a function of protecting the transparent conductive layer from moisture, sulfide, sulfur-containing components, etc. in the atmosphere, so that it is also formed in the insulating region b of the transparent conductive film 100. It is preferable that

The first high refractive index layer 2 is a layer that preferably contains zinc sulfide (ZnS). When zinc sulfide is contained in the first high refractive index layer 2, it becomes difficult for moisture to permeate from the transparent resin support 1 side, and corrosion of the transparent conductive layer 3 is suppressed. The first high refractive index layer 2 may contain other dielectric material or oxide semiconductor material together with zinc sulfide. The refractive index of light having a wavelength of 570 nm of the dielectric material or oxide semiconductor material contained together with zinc sulfide is preferably 0.1 to 1.1 higher than the refractive index of light having a wavelength of 570 nm of the transparent resin support 1. More preferably, it is larger by 4 to 1.0. On the other hand, the specific refractive index of light having a wavelength of 570 nm of the dielectric material or oxide semiconductor material contained in the first high refractive index layer 2 is preferably larger than 1.5, and is 1.7 to 2.5. More preferably, it is 1.8 to 2.5. When the refractive index of the dielectric material or the oxide semiconductor material is larger than 1.5, the optical admittance of the conductive region a of the transparent conductor 100 is sufficiently adjusted by the first high refractive index layer 2. The refractive index of the first high refractive index layer 2 is adjusted by the refractive index of the material included in the first high refractive index layer 2 and the density of the material included in the first high refractive index layer 2. The refractive index is measured with an ellipsometer in an environment of 23 ° C. and 55% RH.

The dielectric material or oxide semiconductor material contained in the first high refractive index layer 2 may be an insulating material or a conductive material. The dielectric material or oxide semiconductor material can be a metal oxide. Examples of the metal oxide include SiO ₂ , TiO ₂ , ITO (indium tin oxide), ZnO, Nb ₂ O ₅ , ZrO ₂ , CeO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , Ti ₄ O _7. , Ti ₂ O ₃ , TiO, SnO ₂ , La ₂ Ti ₂ O ₇ , IZO (indium zinc oxide), AZO (aluminum zinc oxide), GZO (Ga zinc oxide), ATO (antimony tin) Oxide), ICO (indium cerium oxide), IGZO (indium gallium zinc oxide), Bi ₂ O ₃ , Ga ₂ O ₃ , GeO ₂ , WO ₃ , HfO ₂ , a-GIO (gallium, indium , And an amorphous oxide composed of oxygen). The first high refractive index layer 2 may contain only one kind of the metal oxide or two or more kinds.

Of the materials used together with the zinc sulfide, SiO ₂ is particularly preferable. As a method for controlling the composition of ZnS and SiO ₂ , for example, a sputtering method using a ZnS target containing SiO ₂ at an appropriate concentration, or a co-sputtering method using SiO ₂ and ZnS targets simultaneously is used. Can be performed.

When SiO ₂ is contained within the above range together with zinc sulfide, the first high refractive index layer is likely to be amorphous, and the flexibility of the transparent conductive film is likely to be enhanced.

When the first high refractive index layer 2 contains other materials together with zinc sulfide, the amount of zinc sulfide may be 0.1 to 95% by volume with respect to the total volume of the first high refractive index layer 2. Preferably, it is 50 to 90% by volume or less, and more preferably 60 to 85% by volume or less. When the ratio of zinc sulfide is high, the sputtering rate is increased, and the formation rate of the first high refractive index layer 2 is increased. On the other hand, when many components other than zinc sulfide are contained, the amorphous nature of the first high refractive index layer 2 is increased, and cracking of the first high refractive index layer 2 is suppressed.

The layer thickness of the first high refractive index layer 2 is preferably 15 to 150 nm, more preferably 20 to 80 nm. When the layer thickness of the first high refractive index layer 2 is 15 nm or more, the optical admittance of the conductive region a of the transparent conductive film 100 is sufficiently adjusted by the first high refractive index layer 2. On the other hand, if the thickness of the first high refractive index layer 2 is 150 nm or less, the light transmittance of the region including the first high refractive index layer 2 is unlikely to decrease. The layer thickness of the first high refractive index layer 2 is measured by an ellipsometer “multi-incidence angle spectroscopic ellipsometer VASE (registered trademark)” (manufactured by JA Woollam).

The first high refractive index layer 2 is formed by a general vapor deposition method (also called a deposition method or a vapor deposition method) such as a vacuum deposition method, a sputtering method, an ion plating method, a plasma CVD method, a thermal CVD method, or the like. It can be a layer formed of From the standpoint that the refractive index (density) of the first high refractive index layer 2 is increased, the first high refractive index layer 2 is preferably a layer formed by an electron beam evaporation method or a sputtering method. In the case of the electron beam evaporation method, it is desirable to have assistance such as IAD (ion assist) in order to increase the film density.

Further, when the first high refractive index layer 2 is a layer patterned in a desired shape, the patterning method is not particularly limited. The first high refractive index layer 2 may be, for example, a layer formed in a pattern by a vapor deposition method by placing a mask or the like having a desired pattern on the deposition surface. It may be a layer patterned by a method.

<3. First sulfurization prevention layer>
Since the first high refractive index layer 2 contains zinc sulfide, ZnO (zinc oxide) is contained between the first high refractive index layer 2 and the transparent conductive layer 3 as shown in FIG. The first sulfidation preventing layer 5a is preferably included. The first sulfurization preventing layer 5a has a function of preventing diffusion of sulfides and sulfur-containing components from the first high refractive index layer. Further, the first sulfidation preventing layer 5a may also be formed in the insulating region b of the transparent conductive film 100. In this case, the transparent conductive layer is made transparent from moisture, sulfide, sulfur-containing components, etc. in the atmosphere. Since it has a function of protecting the layer, it is preferably formed also in the insulating region b.

The first antisulfurization layer 5a is a layer that preferably contains zinc oxide, and may be a layer that contains a metal oxide, a metal nitride, a metal fluoride, and the like. The first sulfidation preventing layer 5a may contain only one kind or two or more kinds. However, when the first high refractive index layer 2, the first sulfidation preventing layer 5a, and the transparent conductive layer 3 are continuously formed, the metal oxide can react with sulfur or adsorb sulfur. A compound is preferred. In the case where the metal oxide is a compound that reacts with sulfur, the reaction product of the metal oxide and sulfur preferably has high visible light permeability.

Examples of metal oxides include ZnO, TiO ₂ , ITO, Nb ₂ O ₅ , ZrO ₂ , CeO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , Ti ₄ O ₇ , Ti ₂ O ₃ , TiO, SnO ₂ , La ₂ Ti ₂ O ₇ , IZO, AZO, GZO, ATO, ICO, Bi ₂ O ₃ , a-GIO, Ga ₂ O ₃ , GeO ₂ , SiO ₂ , Al ₂ O ₃ , HfO ₂ , SiO, MgO, Y ₂ O ₃ , WO ₃ , etc. are included.

Examples of metal fluorides include LaF ₃ , BaF ₂ , Na ₅ Al ₃ F ₁₄ , Na ₃ AlF ₆ , AlF ₃ , MgF ₂ , CaF ₂ , BaF ₂ , CeF ₃ , NdF ₃ , YF _{3 and the} like. .

Examples of the metal nitride include Si ₃ N ₄ , AlN, and the like.

Among these, a layer containing zinc oxide is preferable.

Here, the layer thickness of the first sulfidation preventing layer 5a is preferably a layer thickness capable of protecting the surface of the first high refractive index layer 2 from an impact when forming the transparent conductive layer 3 described later. On the other hand, ZnS that can be contained in the first high refractive index layer has a high affinity with the metal contained in the transparent conductive layer 3. Therefore, if the thickness of the first anti-sulfurization layer 5a is very thin and a part of the first high refractive index layer 2 is slightly exposed, a transparent metal film of the transparent conductive layer grows around the exposed part. However, the transparent conductive layer 3 tends to be dense. That is, the first sulfidation preventing layer 5a is preferably relatively thin, preferably 0.1 to 5.0 nm, and more preferably 0.5 to 2.0 nm.

The first antisulfurization layer 5a is a layer formed by a general vapor deposition method such as a vacuum deposition method, a sputtering method, an ion plating method, a plasma CVD method, a thermal CVD method or the like.

When the first antisulfurization layer 5a is a layer patterned into a desired shape, the patterning method is not particularly limited. The first sulfidation preventing layer 5a may be a layer formed in a pattern by a vapor deposition method, for example, by placing a mask having a desired pattern on the deposition surface, and may be a known etching method. It may be a layer patterned by.

<4. Transparent conductive layer>
The transparent conductive layer 3 is a film for conducting electricity in the transparent conductive film 100. As described above, the transparent conductive layer 3 may be formed on the entire surface of the transparent resin support 1, or may be patterned into a desired shape.

The transparent conductive layer 3 is a layer containing silver and may contain other metals. The metal used together with silver is not particularly limited as long as it is a metal having high transparent conductivity. For example, gold, copper, nickel, palladium, platinum, zinc, aluminum, manganese, germanium, bismuth, neodymium, and molybdenum are preferable.

Among these, gold, palladium, germanium, bismuth, copper, platinum, neodymium and niobium are preferable. The transparent conductive layer 3 may contain only one kind of these metals or two or more kinds. From the viewpoint of conductivity, the transparent conductive layer is preferably made of an alloy containing 90 atm% or more of silver. When silver is contained at 90 atm% or more, excellent conductivity and high durability can be obtained.

Further, when at least one kind of the above highly conductive metal is contained within the above range, predetermined conductivity can be secured even if the thickness of the transparent conductive layer is reduced, and it is contained in the transparent conductive layer. The effect of preventing silver deterioration is obtained and the reliability is improved. For example, when silver and zinc are combined, the sulfidation resistance of the transparent metal film is enhanced. When silver and gold are combined, salt resistance (NaCl) resistance increases. Furthermore, when silver and copper are combined, the oxidation resistance increases.

The layer thickness of the transparent conductive layer of the present invention is in the range of 3 to 15 nm, preferably in the range of 5 to 13 nm. The desired transparency and plasmon absorption rate can be ensured by this layer thickness.

The plasmon absorption rate of the transparent conductive layer 3 is preferably 10% or less (over the entire range) over a wavelength range of 400 to 800 nm, more preferably 7% or less, and even more preferably 5% or less.

The transparent conductive layer 3 can be a film formed by any method, but in order to change the average transmittance of the transparent conductive layer, it is formed on a film formed by sputtering or an underlayer described later. It is preferable to use a film.

In the sputtering method, when the layer is formed, the material collides with the deposition target at high speed, so that a dense and smooth film can be easily obtained, and the light transmittance of the transparent conductive layer 3 is likely to be increased. Moreover, when the transparent conductive layer 3 is a film formed by sputtering, the transparent conductive layer 3 is hardly corroded even in an environment of high temperature and low humidity.

The type of the sputtering method is not particularly limited, and may be an ion beam sputtering method, a magnetron sputtering method, a reactive sputtering method, a bipolar sputtering method, a bias sputtering method, a counter sputtering method, or the like. The transparent conductive layer 3 is particularly preferably a film formed by a counter sputtering method. When the transparent conductive layer 3 is a film formed by a counter sputtering method, the transparent conductive layer 3 becomes dense and the surface smoothness is likely to increase. As a result, the surface electrical resistance of the transparent conductive layer 3 becomes lower and the light transmittance is likely to increase.

<5. Second anti-sulfur layer>
When the second high refractive index layer described later is a zinc sulfide-containing layer, as shown in FIG. 2, the second sulfide containing zinc oxide between the transparent conductive layer 3 and the second high refractive index layer 4 is used. It is preferable that the prevention layer 5b is included. The second sulfidation preventing layer 5b may be formed also in the insulating region b of the transparent conductive film 100, but from the viewpoint of making it difficult to visually recognize the pattern formed of the conductive region a and the insulating region b, only the conductive region a. It is preferable to be formed.

The second anti-sulfurization layer 5b is a layer containing zinc oxide, and is a layer containing a metal oxide, a metal nitride, a metal fluoride, and the like. In addition to zinc oxide, only one of these may be contained in the second sulfurization prevention layer 5b, or two or more thereof may be contained. The metal oxide, metal nitride, and metal fluoride may be the same as the metal oxide, metal nitride, and metal fluoride contained in the first high refractive index layer 2 described above. Among these, a layer containing zinc oxide is preferable.

On the other hand, the thickness of the second antisulfurization layer 5b is preferably a thickness capable of protecting the surface of the transparent conductive layer 3 from an impact when forming the second high refractive index layer 4 described later. On the other hand, the metal contained in the transparent conductive layer 3 and the ZnS contained in the second high refractive index layer 4 have high affinity. Therefore, if the thickness of the second antisulfurization layer 5b is very thin and a part of the transparent conductive layer 3 is slightly exposed, the transparent conductive layer 3, the second antisulfurization layer 5b, and the second high refractive index layer. Adhesion with 4 tends to increase. Therefore, the specific layer thickness of the second sulfidation preventing layer 5b is preferably 0.1 to 5.0 nm, and more preferably 0.5 to 2.0 nm. The layer thickness of the second sulfurization preventing layer 5b is measured with an ellipsometer.

The second antisulfurization layer 5b may be a layer formed by a general vapor deposition method such as a vacuum deposition method, a sputtering method, an ion plating method, a plasma CVD method, a thermal CVD method, or the like.

When the second antisulfurization layer 5b is a layer patterned into a desired shape, the patterning method is not particularly limited. The second antisulfurization layer 5b may be a layer formed in a pattern by a vapor deposition method, for example, by placing a mask having a desired pattern on the deposition surface, and may be a known etching method. It may be a layer patterned by.

<6. Second High Refractive Index Layer>
The second high refractive index layer 4 is a layer for adjusting the light transmittance (optical admittance) of the conductive region a of the transparent conductive film 100, that is, the region where the transparent conductive layer 3 is formed. The conductive film 100 is formed in the conduction region a. The second high-refractive index layer 4 may be formed in the insulating region b of the transparent conductive film 100, but from the viewpoint of making it difficult to visually recognize the pattern composed of the conductive region a and the insulating region b, only the conductive region a. Preferably it is formed. Since the second high refractive index layer 4 makes it difficult for moisture to permeate from the atmosphere side, it has an effect of suppressing the corrosion of the transparent conductive layer 3.

The second high refractive index layer 4 is a layer having a refractive index higher than the refractive index of the transparent resin support 1 described above, and one of the first high refractive index layers contains zinc sulfide (ZnS). It is. The second high refractive index layer 4 may include zinc sulfide or other dielectric material or oxide semiconductor material. The refractive index of light having a wavelength of 570 nm of zinc sulfide or other dielectric material or oxide semiconductor material is preferably 0.1 to 1.1 higher than the refractive index of light having a wavelength of 570 nm of the transparent substrate 1. More preferably, it is larger by 1.0.

On the other hand, the specific refractive index of light having a wavelength of 570 nm of the dielectric material or the oxide semiconductor material contained in the second high refractive index layer 4 is preferably larger than 1.5 and is 1.7 to 2.5. More preferably, it is 1.8 to 2.5. When the refractive index of the dielectric material or the oxide semiconductor material is larger than 1.5, the optical admittance of the conductive region a of the transparent conductive film 100 is sufficiently adjusted by the second high refractive index layer 4. The refractive index of the second high refractive index layer 4 is adjusted by the refractive index of the material included in the second high refractive index layer 4 and the density of the material included in the second high refractive index layer 4.

The dielectric material or oxide semiconductor material contained in the second high refractive index layer 4 may be an insulating material or a conductive material. The dielectric material or oxide semiconductor material can be a metal oxide. Examples of the metal oxide include SiO ₂ , TiO ₂ , ITO (indium tin oxide), ZnO, Nb ₂ O ₅ , ZrO ₂ , CeO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , Ti ₄ O _7. , Ti ₂ O ₃ , TiO, SnO ₂ , La ₂ Ti ₂ O ₇ , IZO (indium zinc oxide), AZO (aluminum zinc oxide), GZO (gallium zinc oxide), ATO (antimony tin) Oxide), ICO (indium cerium oxide), IGZO (indium gallium zinc oxide), Bi ₂ O ₃ , Ga ₂ O ₃ , GeO ₂ , WO ₃ , HfO ₂ , a-GIO (gallium, indium , And an amorphous oxide composed of oxygen). The second high refractive index layer 4 may include only one kind of the metal oxide or two or more kinds.

In the present invention, among the above metal oxides, ITO, IZO, GZO, and IGZO are preferable. These materials are suitable for patterning and at the same time can provide a protective function for silver.

In the present invention, zinc sulfide (ZnS) is particularly preferable as the dielectric material or oxide semiconductor material contained in the second high refractive index layer 4. When ZnS is contained in the second high refractive index layer 4, it becomes difficult for moisture to permeate from the transparent resin support 1 side, and corrosion of the transparent conductive layer 3 is suppressed. The second high refractive index layer 4 may contain only ZnS or may contain other materials together with ZnS. Materials included with ZnS is a metal oxide or SiO ₂ or the like, which may be the dielectric material or an oxide semiconductor material, particularly preferably SiO _2. When SiO ₂ is contained together with ZnS, the second high refractive index layer is likely to be amorphous, and the flexibility of the transparent conductor is likely to be enhanced.

When the second high refractive index layer 4 contains other materials together with ZnS, the amount of ZnS is preferably 0.1 to 95% by volume with respect to the total volume of the second high refractive index layer 4. The content is more preferably 50 to 90% by volume or less, and still more preferably 60 to 85% by volume. When the ratio of ZnS is high, the sputtering rate increases and the formation rate of the second high refractive index layer 4 increases. On the other hand, when many components other than ZnS are contained, the amorphous nature of the second high refractive index layer 4 increases, and cracking of the second high refractive index layer 4 is suppressed.

As a method for controlling the composition of zinc sulfide and SiO ₂ within the above range, for example, a sputtering method using a ZnS target containing SiO ₂ at an appropriate concentration, or co-sputtering using a SiO ₂ and ZnS target simultaneously. This can be done by using the law.

When SiO ₂ is contained within the above range together with zinc sulfide, the second high refractive index layer is likely to be amorphous, and the flexibility of the transparent conductive film is likely to be enhanced.

When the ratio of ZnS is high, the sputtering rate increases and the formation rate of the second high refractive index layer 4 increases. On the other hand, when the amount of components other than ZnS increases, the amorphousness of the second high refractive index layer 4 increases, and cracking of the second high refractive index layer 4 is suppressed.

The layer thickness of the second high refractive index layer 4 is preferably 15 to 150 nm, and more preferably 20 to 80 nm. When the layer thickness of the second high refractive index layer 4 is 15 nm or more, the optical admittance of the conductive region a of the transparent conductor 100 is sufficiently adjusted by the second high refractive index layer 4. On the other hand, if the layer thickness of the second high refractive index layer 4 is 150 nm or less, the light transmittance of the region including the second high refractive index layer 4 is unlikely to decrease. The layer thickness of the second high refractive index layer 4 is measured with an ellipsometer.

The formation method of the second high refractive index layer 4 is not particularly limited, and is a layer formed by a general vapor deposition method such as a vacuum deposition method, a sputtering method, an ion plating method, a plasma CVD method, a thermal CVD method, or the like. It can be. From the viewpoint that the moisture permeability of the second high refractive index layer 4 is lowered, the second high refractive index layer 4 is particularly preferably a film formed by a sputtering method.

Further, when the second high refractive index layer 4 is a layer patterned into a desired shape, the patterning method is not particularly limited. The second high refractive index layer 4 may be, for example, a layer formed in a pattern by a vapor deposition method by disposing a mask having a desired pattern on the deposition surface. Moreover, the layer patterned by the well-known etching method may be sufficient.

<7. Hard coat layer>
A hard coat layer is provided on at least one surface of the transparent resin support, preferably on the transparent conductive layer side, for the purpose of preventing scratches on the surface of the transparent resin support during the production of the transparent conductive film. It is preferable.

By providing a hard coat layer on at least one surface of the transparent resin support, the film can be wound, conveyed, and unwound in the production process of the transparent conductive film of the present invention from the time of forming the transparent resin support. It has the effect of preventing the occurrence of scratches due to surface pressure and friction between the film surfaces.

The hard coat layer is provided by applying and drying an ultraviolet curable acrylate resin and then curing with an ultraviolet light source.

The layer thickness of the hard coat layer is preferably in the range of 0.2 to 5.0 μm, and if the layer thickness of the hard coat layer is in the above range, a sufficient scratch resistance effect can be obtained. Since generation | occurrence | production of a damage | wound can be prevented, when it is set as a transparent conductive film, sufficient transparency is obtained.

The hard coat layer can be produced by laminating a SiO ₂ thin film by a CVD method, a sputtering method, a vapor deposition method or the like with a layer thickness of 100 nm or less in addition to the application.

<8. Anti-blocking layer>
A blocking prevention layer having a 10-point average roughness Rz of 50 nm or less is provided on the surface of the transparent conductive film of the present invention opposite to the surface provided with the transparent conductive layer of the transparent resin support. preferable. The anti-blocking layer is used to prevent sticking between films when winding and handling the film. This is done by providing an arbitrary roughness on the surface of the film and filling this gap with air. It is possible to prevent sticking between films during unwinding and winding operations.

10-point average roughness Rz means Rz defined in JIS B0601: 1994.

The anti-blocking layer can be provided by applying a coating liquid in which fine particles are mixed with a resin such as an acrylate resin. In addition to inorganic fine particles such as silica, resin fine particles can be used as the fine particles. The average particle diameter of the fine particles is preferably within the range of 10 to 300 nm.

In the transparent conductive film of the present invention, each thin film layer of a high refractive index layer, an antisulfurization layer and a transparent conductive layer provided on a transparent resin support is formed by a sputtering method or a vapor deposition method. Is preferred. When each thin film layer provided on the transparent resin support is formed by a sputtering method or a vapor deposition method, productivity is improved and an effect suitable for mass production is obtained. However, the value obtained by the present invention is not impaired even by any other thin film manufacturing method such as chemical vapor deposition (CVD).

≪Patterning of transparent conductive layer≫
For example, in order to produce a capacitive touch panel using the transparent conductive film of the present invention, as shown in FIG. 4, the transparent conductive layer is divided into a plurality of conductive regions a and a line-shaped insulating region that divides the conductive regions a. It is preferable to pattern it into a predetermined shape including b.

Examples of the deterioration factor of the transparent conductive layer containing silver include moisture and sulfide contained in the atmosphere. These are taken into the transparent resin support and the hard coat layer, and pass through the hard coat layer to reach the transparent conductive layer. Therefore, the transparent resin support and the hard coat layer alone do not provide sufficient silver protective function for the transparent conductive layer. Therefore, if there is a first high refractive index layer, preferably a first antisulfurization layer, the antisulfurization layer is included. From the viewpoint of preventing the deterioration of the transparent conductive layer, it is preferable to leave it on the transparent resin support without being patterned.

As a method of patterning the transparent conductive layer, a known method can be used. Specifically, such a patterning method can be performed as follows.

(Patterning process)
Hereinafter, a method for forming an electrode pattern by photolithography will be described.

The photolithographic method applied to the present invention includes resist coating such as curable resin, preheating, exposure, development (removal of uncured resin), rinsing, etching treatment with an etching solution, and resist stripping. The transparent conductive layer is processed into a desired pattern as shown in FIG.

In the present invention, a conventionally known general photolithography method can be used as appropriate. For example, as the resist, either positive or negative resist can be used. In addition, after applying the resist, preheating or prebaking can be performed as necessary. At the time of exposure, a pattern mask having a desired pattern may be disposed, and light having a wavelength suitable for the resist used, generally ultraviolet rays, electron beams, or the like may be irradiated thereon. After the exposure, development is performed with a developer suitable for the resist used.

After development, a resist pattern is formed by stopping development with a rinse solution such as water and washing. Next, the formed resist pattern is pretreated or post-baked as necessary, and then is etched with an etching solution containing an organic solvent to dissolve the intermediate layer in a region not protected by the resist and to form a silver thin film electrode Remove.

After etching, the remaining resist is removed to obtain a transparent electrode having the desired pattern. As described above, the photolithography method applied to the present invention is a method generally recognized by those skilled in the art, and the specific application mode is easily selected by those skilled in the art according to the intended purpose. be able to.

Next, an electrode pattern forming method applicable to the present invention will be described with reference to FIGS. 5A to 5G.

FIG. 5A to FIG. 5G are process flow diagrams showing an example of forming an electrode pattern on the transparent conductor of the present invention by a photolithography method.

As a first step, as shown in FIG. 5A, on the transparent resin support 1, a first high refractive index layer 2, a first antisulfurization layer 5a, a transparent conductive layer 3, a second antisulfurization layer 5b, and a second high A transparent conductive film 100 in which the refractive index layer 4 is laminated in this order is produced.

Next, in the resist film forming step shown in FIG. 5B, a resist film 6 composed of a photosensitive resin composition or the like is uniformly coated on the transparent conductive film 100. As the photosensitive resin composition, a negative photosensitive resin composition or a positive photosensitive resin composition can be used.

As a coating method, it is applied on the transparent conductive film 100 by a known method such as microgravure coating, spin coating, dip coating, curtain flow coating, roll coating, spray coating, slit coating, hot plate, oven, etc. It can be pre-baked with a heating device. Pre-baking can be performed, for example, using a hot plate or the like in the range of 50 ° C. or higher and 150 ° C. or lower for 30 seconds to 30 minutes.

Next, in the exposure step shown in FIG. 5C, an exposure machine such as a stepper, a mirror projection mask aligner (MPA), a parallel light mask aligner or the like is used through a mask 7 made with a predetermined electrode pattern, and 10 to 4000 J / m. ^The resist film 6A to be removed in the next step is irradiated with light of about ² (wavelength 365 nm exposure amount conversion). The exposure light source is not limited, and ultraviolet rays, electron beams, KrF (wavelength 248 nm) laser, ArF (wavelength 193 nm) laser, and the like can be used.

Next, in the developing step shown in FIG. 5D, the exposed transparent conductive film is immersed in a developing solution to dissolve the resist film 6A in the region irradiated with light.

As the developing method, it is preferable to immerse in the developer for 5 seconds to 10 minutes by a method such as showering, dipping or paddle. As the developer, a known alkali developer can be used. Specific examples include inorganic alkalis such as alkali metal hydroxides, carbonates, phosphates, silicates and borates, amines such as 2-diethylaminoethanol, monoethanolamine and diethanolamine, tetramethylammonium hydroxide. Examples thereof include aqueous solutions containing one or more quaternary ammonium salts such as side and choline. After development, it is preferable to rinse with water, and then dry baking may be performed in the range of 50 ° C. to 150 ° C.

Thereafter, “PURE ETCH 100” manufactured by Hayashi Pure Chemical Industries, Ltd. is used as an etchant to remove the second high refractive index layer and the second antisulfurization layer. (Fig. 5E)
Next, “SEA-5” manufactured by Kanto Chemical Co., Inc. is carried out in a short time etching in order to dissolve only the transparent conductive layer and the first antisulfuration layer. (Fig. 5F)
Finally, as shown in FIG. 5G, the resist film 6 is removed by immersing it in a resist film remover, for example, “N-300” manufactured by Nagase ChemteX Corporation, leaving the first high refractive index layer 2. A transparent conductive film having an electrode pattern can be produced.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

≪Preparation of transparent conductive film≫
For the production of the transparent conductive film, the following transparent resin support and conductive material were used.

1. TPS1: “Zero tack” manufactured by Konica Minolta Co., Ltd., thickness 50 μm Ro = 0 nm Rt = 0 nm n = 1.50
2. TPS2: Konica Minolta Co., Ltd. “Konica Minolta Tack” thickness 50 μm Ro = 5 nm Rt = 30 nm n = 1.48
3. TPS3: “Zero tack” manufactured by Konica Minolta Co., Ltd. was stretched and adjusted to a thickness of 50 μm Ro = 3 nm and Rt = 3 nm. n = 1.50

4. TPS4: “Konica Minolta Tac” manufactured by Konica Minolta Co., Ltd. was stretched and adjusted to a thickness of 50 μm, Ro = 15 nm, and Rt = 30 nm. n = 1.48

5. PET1: Toyobo polyethylene terephthalate film “Cosmo Shine A4300” thickness 50 μm Ro = 5000 nm Rt = 10000 nm n = 1.60
6). PC1: Kaneka polycarbonate film “Elmec R40 # 435 film” thickness 40 μm Ro = 435 nm Rt = 600 nm n = 1.58
7). TPS5: Kaneka polycarbonate film “Elmec R40 # 140 film” thickness 40 μm Ro = 140 nm Rt = 350 nm n = 1.58
8). TPS6: ZEON cycloolefin film “ZEONOR Z14 (50 μm)” thickness 50 μm Ro = 1.5 nm Rt = 10 nm n = 1.53
9. TPS7: “VA-TAC” manufactured by Konica Minolta Co., Ltd. thickness 80 μm Ro = 50 nm Rt = 130 nm n = 1.48
10. PET2: Biaxially stretched PET Thickness 50 μm Ro = 1500 nm Rt = 5000 nm n = 1.60
11. APC: Furuya Metal "Ag alloy" (containing Pd and Cu)
12 APC-TR: “Ag alloy” made of Furuya Metal (containing Pd and Cu)
13. APC-SR: Furuya Metal's “Ag alloy” (containing Pd and Cu)
The above three grade alloys have different compositions.

14 GB-100: “Ag alloy” manufactured by Kobelco Research Institute, Ag (99.0 atm%) / Bi (1.0 atm%)
15. GBR-15: “Ag alloy” manufactured by Kobelco Research Institute, Ag (98.35 atm%) / Bi (0.35 atm%) / Ge (0.3 atm%) / Au (1.0 atm%)
16. Ag: (Purity 99.99%)
17. KP801M: “Fluorine-based surface modification material” manufactured by Shin-Etsu Chemical Co., Ltd.
18. a-GIO: amorphous gallium indium oxide19. ITO: Indium tin oxide n = 1.80
20. ZnS: Zinc sulfide n = 2.37
21. SiN: silicon nitride n = 2.02
22. TiO ₂ : Titanium oxide n = 2.52
23. Nb ₂ O ₅ : Niobium pentoxide n = 2.31
24. Au: (Purity 99.99%) n = 0.34
25. ZnO: zinc oxide n = 1.95
26. Cr: metallic chromium 27. ICO: Indium / cerium oxide 28. IZO: Indium / Zinc Oxide n = 2.10
29. GZO: gallium / zinc oxide 30. IGZO: Indium / gallium / zinc oxide In the above, n represents a refractive index.
<Preparation of transparent conductive film 1>
(First high refractive index layer (ZnS—SiO ₂ ))
Using a magnetron sputtering apparatus manufactured by Konica Minolta Co., Ltd. “Zerotack” (Ro = 0 nm, Rt = 0 nm), 50 μm thick, and using a magnetron sputtering apparatus manufactured by Osaka Vacuum Co., Ar 20 sccm, O ₂ 5 sccm, sputtering pressure 0. ZnS—SiO ₂ was RF sputtered at 2 Pa, room temperature, target-side power of 150 W, and formation rate of 3.0 Å / sec (0.3 nm / sec) to form a first high refractive index layer having a layer thickness of 45.0 nm. The target-substrate distance was 90 mm. Ro and Rt were measured with a phase difference measuring device “KOBRA-21ADH” (manufactured by Oji Scientific Instruments) in an environment of 23 ° C. and 55% RH.

The ratio (volume ratio) between ZnS and SiO ₂ was 75:25 (ZnS: 75% by volume).

(Transparent conductive layer (Ag))
On the first high refractive index layer, using a magnetron sputtering apparatus of Osaka Vacuum Co., Ar 20 sccm, sputtering pressure 0.5 Pa, room temperature, target side power 150 W, formation rate 14 Å / sec (1.4 nm / sec) APC-TR (“Ag alloy” manufactured by Furuya Metal Co., Ltd.) was sputtered oppositely to form a transparent conductive layer having a layer thickness of 7.5 nm. The target-substrate distance was 90 mm.

(Second anti-sulfur layer)
Using an Osaka vacuum magnetron sputtering system, Ar 20 sccm, O ₂ 0 sccm, sputtering pressure 0.1 Pa, room temperature, target power 150 W, formation rate 1.1 Å / sec (0.11 nm / sec), ZnO layer thickness RF sputtering was performed so that the thickness became 1.0 nm. The target-substrate distance was 90 mm.

(Second high refractive index layer (ZnO—SiO ₂ ))
On the anti-sulfurization layer, ZnS—SiO ₂ is RF sputtered by the same method as the first high refractive index layer to form a second high refractive index layer having a layer thickness of 45.0 nm. Produced. The volume ratio of ZnS to SiO ₂ was 75:25.

<Preparation of transparent conductive films 2 to 28, 31 to 33>
Transparent conductive films 2 to 28 and 31 to 33 of the present invention were produced in the same manner as the transparent conductive film 1 except that the configurations shown in Tables 1 and 2 were used. Incidentally, ZnS and SiO ₂ ratio was carried out by utilizing a co-sputtering method using ZnS and SiO ₂ targets simultaneously. The layer thickness of each layer was adjusted by adjusting the sputtering time. The first antisulfurization layer and the second antisulfurization layer were both formed by the same method.

<Preparation of transparent conductive films 29 and 30>
TPS3 is used as a transparent resin support, and one electronic heating evaporation source provided in GENER1300, an OPTRAN vacuum evaporation system, and two resistance heating evaporation sources are used in combination, and all layers are vacuumed as follows: It formed by the vapor deposition method.

First, the first high refractive index layer was made of ZnS—SiO ₂ , ZnS was co-deposited from a resistance heating evaporation source, and SiO ₂ was evaporated from an electron heating evaporation source. At this time, the resistance heating / electron gun current was independently controlled so that the volume ratio of ZnS to SiO ₂ was 75:25. The layer thickness was 45.0 nm.

Next, ZnO was formed as a first anti-sulfuration layer with a layer thickness of 1.0 nm from an electron heating evaporation source. Subsequently, Ag from the first resistance heating evaporation source and Au from the second resistance heating evaporation source were co-deposited as transparent conductive layers, respectively. At this time, the current of each evaporation source was controlled independently so that the ratio of Ag and Au was 98: 2 by weight. The layer thickness was 7.5 nm.

Next, ZnO was formed from the electron heating evaporation source with a layer thickness of 1.0 nm as the second sulfurization prevention layer.

Finally, the second high refractive index layer was made of ZnS—SiO ₂ , ZnS was co-deposited from a resistance heating evaporation source, and SiO ₂ was evaporated from an electron heating evaporation source. At this time, the resistance heating / electron gun current was independently controlled so that the volume ratio of ZnS to SiO ₂ was 75:25. The layer thickness was 45.0 nm, and this was used as the transparent conductive film 29.

The transparent conductive film 30 was produced in the same manner as the transparent conductive film 29 as shown in Table 2.

<Preparation of transparent conductive films 101 to 116>
Transparent conductive films 101 to 116 of comparative examples were produced in the same manner as the transparent conductive film 1 except that the structure shown in Table 3 was used. The transparent conductive films 112 and 113 were produced by the following method.

<Transparent conductive film 112>
Toyobo PET (Cosmo Shine A4300 thickness 50 μm) was used for the transparent resin support. To this, Nb ₂ O ₅ was formed as a first high refractive index layer with a layer thickness of 27.5 nm. However, for the Nb ₂ O ₅ layer, L-430S-FHS manufactured by Anelva is used, Ar 20 sccm, O ₂ 1 sccm, sputtering pressure 0.5 Pa, room temperature, target side power 150 W, formation rate 1.2 Å / sec (0 Nb ₂ O ₅ was DC sputtered at .12 nm / sec). The target-substrate distance was 86 mm. Subsequently, Ag was formed as a transparent conductive layer to a layer thickness of 7.3 nm using a sputtering apparatus manufactured by Osaka Vacuum. Subsequently, IZO was formed to a layer thickness of 36.0 nm as the second high refractive index layer. This was designated as transparent conductive film 112.

<Transparent conductive film 113>
Using “Zerotack” manufactured by Konica Minolta Co., Ltd., Ro was set to 3 nm by adding a stretching step before drying. The first high refractive index layer was made of ICO and had a layer thickness of 27.0 nm. Subsequently, Cr was formed as a first sulfurization prevention layer with a layer thickness of 0.8 nm, and further, an Ag—Au alloy was prepared as a transparent conductive layer, and an alloy prepared so as to contain Ag and Au at 98 atm% and 2 atm%, respectively. Was used as a target and the layer thickness was 9.0 nm. Subsequently, Cr was formed as a second anti-sulfuration layer with a layer thickness of 0.8 nm, and ICO was formed thereon as a second high refractive index layer with a layer thickness of 27.0 nm.

Next, SiO ₂ was again formed with a layer thickness of 40.0 nm on the second high refractive index layer. Furthermore, “KP801M”, which is a fluorine-based surface modifying material, was deposited by resistance heating vapor deposition at 190 mA and a forming rate of 10 Å / sec (1 nm / sec) with a Gener 1300 manufactured by Optorun to form a layer thickness of 6.0 nm. This was designated as a transparent conductive film 113.

≪Evaluation method≫
The transparent conductive films 1 to 33 of the present invention produced as described above and the transparent conductive films 101 to 116 of the comparative example were evaluated as follows.

<Angle-dependent rainbow unevenness>
The angle-dependent rainbow unevenness was evaluated by performing patterning processing imitating electrodes on a transparent conductive film provided in a 10-inch size (1 inch = 2.54 cm) and pasting it on an LCD display panel to form an out-cell touch panel Then, a color chart is projected on the screen and a visual test is performed on a video from an angle of 45 degrees with respect to the normal direction in a blind manner, and comparison judgment is made with the maximum number of answers.

(Evaluation criteria)
○: No rainbow unevenness is observed Δ: Minor rainbow unevenness is observed ×: Rainbow unevenness is generated to the extent that visibility is impaired <Surface resistance (conductivity)>
The initial surface resistance of the transparent conductive film was measured using a low resistivity meter “Loresta-EP” (manufactured by Mitsubishi Chemical Analytech Co., Ltd.).

(Evaluation criteria)
◎: Less than 10Ω / □ ○: Less than 10Ω / □ △: 10Ω / □ or more and less than 15Ω / □ X: Less than 15Ω / □ <Transparency evaluation>
The initial transparency of the transparent conductive film was measured by measuring the average transmittance at a measurement wavelength of 400 to 800 nm using a spectrophotometer “U4100” (manufactured by Hitachi High-Tech).

Assuming that this measurement is applied to a transmissive capacitive touch panel, in order to reflect the actual system, a transparent conductive film comprising a support, a high refractive index layer, an antisulfurization layer and a transparent conductive layer is used. The evaluation was performed by pasting on a glass substrate with immersion oil “type A (n = 1.515)” (manufactured by Nikon Corporation) used in the oil immersion optical system and measuring the total transmittance.

The average transmittance was measured by making light incident from an angle inclined by 5 ° with respect to the normal of the surface of the transparent conductive film on the transparent resin support side.

(Evaluation criteria)
◎: Average transmittance is 92% or more ○: Average transmittance is 90% or more and less than 92% △: Average transmittance is 85% or more and less than 90% ×: Average transmittance is less than 85% The results of the evaluation are shown in Table 4.

Based on the above results, the conductive films 1 to 33 of the present invention provide a transparent conductive film having good conductivity and transparency and capable of displaying beautiful images with no rainbow unevenness having angle dependency. I understand that I can do it.

On the other hand, the transparent conductive films 101 to 116 prepared as comparative examples for the effects of the present invention were inferior in various properties as compared with the present invention.

The transparent conductive film 101 had insufficient transmittance because the thickness of the conductive layer containing silver was too thick.

As a result of using ITO for the conductive layer, the transparent conductive film 102 was remarkably inferior in terms of conductivity.

The transparent conductive film 103 uses gold for the conductive layer, but due to the refractive index wavelength dispersion property of gold, high transparency in the entire visible range could not be secured, and as a result, the average transmittance was insufficient.

In the transparent conductive films 104 to 106 and 111, since the retardation of the transparent resin support was too large, the angle-dependent rainbow unevenness was remarkably generated.

The transparent conductive film 107 is inferior in overall transmittance as a result of the absence of the second high refractive index layer having a function of adjusting the optical admittance, so that a portion with a small amount of incident light energy is directed to reflection. It was.

The transparent conductive film 108 was not preferable in terms of transmittance because the first high refractive index layer for adjusting the optical admittance was not present, and the conductivity was slightly insufficient. This is because the base when the ZnO as the first anti-sulfurization layer is formed is the surface of the support, which is an exposed organic substance, so that the ZnO thin film explained by the island-like nuclei in the growth mode of the Volmer-Weber As a result of the fact that the microscopic structural characteristics have a strong agglomeration property, it is presumed that the conductive layer formed immediately after that is also affected by this, and the film also has a strong granular interfacial property.

The transparent conductive films 109, 110, 112, 114 and 115 also have refractive index wavelength dispersion characteristics specific to various materials such as SiN, TiO ₂ , Nb ₂ O ₅ , ITO and GIO selected instead of ZnS as the high refractive index layer. Therefore, the adjustment of the optical admittance became insufficient and the conductivity was slightly inferior. Regarding this lack of conductivity, the physicochemical properties of the surface on which the conductive layer is formed are different from those of the layer using sulfide, so that the microscopic structure of the conductive layer becomes homogeneous and continuous. Presumed to be missing.

The transparent conductive film 116 was inferior in terms of conductivity because the thickness of the conductive layer was too thin.

The above comparative example clearly shows the effect and superiority of the transparent conductive film provided by the present invention.

The present invention can be suitably used for a transparent conductive film having good conductivity and transparency and capable of displaying a beautiful image without rainbow unevenness having angle dependency.

DESCRIPTION OF SYMBOLS 100 Transparent conductive film 200 Polarizing plate 300 Image display element 1 Transparent resin support body 2 1st high refractive index layer 3 Transparent conductive layer 4 2nd high refractive index layer 5a 1st sulfidation prevention layer 5b 2nd sulfation prevention layer 6 Resist film 6A Resist film to be removed 7 Mask 8 Exposure unit EU Transparent electrode unit a Conductive region b Insulating region

Claims (7)

1. A transparent conductive film having at least one transparent conductive layer and a high refractive index layer on a transparent resin support,
   The in-plane retardation value Ro of the transparent resin support at a measurement wavelength of 589 nm is in the range of 0 to 150 nm,
   The transparent conductive layer contains silver and has a layer thickness in the range of 3 to 15 nm;
   The transparent conductive film, wherein the high refractive index layer is provided on both sides of the transparent conductive layer, and at least one high refractive index layer contains zinc sulfide.
2. 2. The transparent conductive film according to claim 1, wherein the retardation value Rt in the thickness direction at a measurement wavelength of 589 nm of the transparent resin support is in the range of 0 to 400 nm.
3. 3. The transparent conductive film according to claim 1, wherein the transparent resin support contains at least one selected from a cellulose ester resin, a cycloolefin resin, and a polycarbonate resin.
4. The transparent conductive layer contains at least one metal selected from gold, copper, nickel, palladium, platinum, zinc, aluminum, manganese, germanium, bismuth, neodymium and molybdenum. Item 4. The transparent conductive film according to any one of Items 3 to 3.
5. 5. The high refractive index layer on the support side among the high refractive index layers provided on both sides of the transparent conductive layer contains zinc sulfide. 5. The transparent conductive film as described.
6. Among the high refractive index layers provided on both sides of the transparent conductive layer, the high refractive index layer provided on the side opposite to the support side is composed of indium tin oxide, indium zinc oxide, gallium zinc oxide. The transparent conductive film according to any one of claims 1 to 5, further comprising any one of indium, gallium, and zinc oxide.
7. The transparent conductive material according to any one of claims 1 to 6, further comprising a layer containing zinc oxide between the transparent conductive layer and the at least one high refractive index layer. the film.

Images