Transparent electroconductive film

Abstract

The present invention provides a transparent electroconductive film that exhibits excellence in all of continuous input durability, sticking resistance, appearance, and silver adhesion.　The transparent electroconductive film according to the present invention has a transparent electroconductive layer of indium-tin composite oxide laminated on at least one surface of a transparent plastic film base material. The transparent electroconductive film is characterized in that: the average arithmetic mean height (AVSa) of the transparent electroconductive layer is between 2 nm and 50 nm, inclusive; the average maximum peak height (AVSp) of the transparent electroconductive layer is between 150 nm and 1000 nm, inclusive; the transparent electroconductive layer–side surface and the surface on the side opposite from the surface on which the transparent electroconductive layer is laminated have an average protrusion width, as determined by test method 1, of not more than 12 µm; the lamination strength of the transparent electroconductive layer, as determined by test method 2, is at least 450 mN / 15 mm; and the silver adhesion of the transparent electroconductive film, as determined by test method A, is at least 95%.

Description

Transparent Conductive Film

[0001] The present invention relates to a transparent conductive film in which a transparent conductive film of indium-tin composite oxide is laminated on a transparent plastic film substrate.

[0002] Transparent conductive films, which are formed by laminating a transparent thin film having low resistance on a transparent plastic film substrate, are widely used in electrical and electronic applications that utilize their conductivity, such as flat panel displays such as liquid crystal displays and electroluminescence (EL) displays, and transparent electrodes for touch panels.

[0003] Resistive touch panels combine a fixed electrode made of a glass or plastic substrate coated with a transparent conductive thin film with a movable electrode (called a film electrode) made of a plastic film coated with a transparent conductive thin film, and are used by overlaying them on top of the display. When the film electrode is pressed with a finger or pen (called input), the transparent conductive thin films of the fixed electrode and the film electrode come into contact with each other, and the input position is recognized.

[0004] Patent Document 1 discloses a transparent conductive film in which a transparent conductive thin film made of indium-tin composite oxide or tin-antimony composite oxide is laminated on a plastic film, and the center line average roughness (Ra) of the transparent conductive thin film surface satisfies 0.1 to 0.5 μm. Patent Document 2 also discloses a transparent conductive film including a support and a transparent conductive layer formed on one surface of the support, in which the surface roughness Ra1 of the surface on the transparent conductive layer side is 7 to 20 nm and the number of protrusions with a height of 250 nm or more is 140 / mm 2 A transparent conductive film that satisfies the following requirements has been disclosed.

[0005] Patent No. 4961697 Patent No. 6425598

[0006] Recently, there has been an increase in demand for resistive touch panels. For example, resistive touch panels must be able to continue inputting even when lightly touched after relatively strong input force with a pen or finger (continuous input durability). It is also important for resistive touch panels to prevent sticking between the fixed electrode and the film electrode (anti-sticking). Furthermore, because the transparent conductive film is positioned as the outermost layer of a resistive touch panel, it must have a good appearance (clear, not whitish, and uniform across the entire surface).

[0007] The inventors have verified that the transparent conductive film described in Patent Document 1 has good anti-sticking properties but poor durability to continuous input, and the entire surface appears whitish due to white dots caused by protrusions on the transparent conductive film. Furthermore, the transparent conductive film described in Patent Document 2 has good durability to continuous input and good appearance, but does not have satisfactory anti-sticking properties.

[0008] In addition, in order to improve the production efficiency of transparent conductive films, a transparent conductive film may be formed directly while the film is being unwound from a film roll. In this case, if the film is wound up again as a film roll after the transparent conductive film formation, when the film is subsequently unwound from the film roll and silver is coated on the transparent conductive film for electrical wiring, the adhesion of the silver may be insufficient, resulting in peeling.

[0009] Therefore, an object of the present invention is to provide a transparent conductive film that is excellent in all of durability against continuous input, anti-sticking properties, appearance, and silver adhesion.

[0010] The present invention has been made in view of the above circumstances, and the transparent conductive film of the present invention, which has been able to solve the above problems, has the following configuration: [1] A transparent conductive film comprising a transparent conductive film of indium-tin composite oxide laminated on at least one surface of a transparent plastic film substrate, wherein the average arithmetic mean height (AVSa) of the transparent conductive film is 2 nm or more and 50 nm or less, the average maximum peak height (AVSp) of the transparent conductive film is 150 nm or more and 1000 nm or less, the average protrusion widths of the surface on the transparent conductive film side and the surface opposite to the surface on which the transparent conductive film is laminated, as determined by Test Method 1 below, are 12 μm or less, the laminate strength of the transparent conductive film is 450 mN / 15 mm or more, as determined by Test Method 2 below, and the silver adhesion of the transparent conductive film is 95% or more, as determined by Test Method A below. [Test Method 1] Particle analysis is performed using a three-dimensional surface profiler, VertScan (measurement conditions: wave mode, measurement wavelength 560 nm, objective lens 50x, field of view 188.709 μm × 141.496 μm) in the following steps (i) to (v). (i) The cross-sectional area (T ｃ This measurement is performed on both the surface on the transparent conductive film side and the surface opposite to the surface on which the transparent conductive film is laminated, and the sum of the cross-sectional areas of all the protrusions on the surface on the transparent conductive film side and the surface opposite to the surface on which the transparent conductive film is laminated is defined as the cross-sectional area of ​​all the protrusions (T ｃ (ii) The average cross-sectional area of ​​all protrusions (the total number of protrusions is N ｐ When this is done, T ｃ / N ｐ (iii) Average value (T ｃ / N ｐ ) and a protrusion having a cross-sectional area 10 times or more of the average value (T ｃ / N ｐ (iv) From the protrusions remaining in (iii), the top 20% and bottom 20% of the protrusions in order of largest cross-sectional area are further removed. (v) For the protrusions remaining in (iv), the average cross-sectional area (A) is calculated, and this value is substituted into the following formula (1) to calculate the average protrusion width (B). Formula (1): Average protrusion width (B) = 2 x (A / π)0.5[Test Method 2] A urethane-based two-component curing adhesive (containing 4% by weight of ethyl acetate as a solvent) is applied to the transparent conductive film side surface using a wire bar #5, and then heated at 60°C for 1 minute. The adhesive-coated surface of the transparent conductive film is then bonded to the PET surface of a 100 μm thick PET film using a dry lamination method (0.3 MPa, width 70 cm) at 60°C, and aged at 40°C for 4 days to obtain a laminate for evaluation. The resulting laminate is cut into a width of 15 mm and a length of 150 mm to prepare a test piece. A T-peel test is performed at a temperature of 23°C, a relative humidity of 65%, and a peel rate of 100 mm / min to measure the maximum load. [Test Method A] A silver paste is applied to the transparent conductive film side to a thickness of 15 μm and heated at 150°C for 30 minutes. Next, an adhesion test is performed in accordance with JIS K5600-5-6:1999. [2] The transparent conductive film according to [1], wherein the transparent conductive film has a thickness of 10 nm or more and 100 nm or less, a tin oxide concentration contained in the transparent conductive film is 0.5 mass % or more and 11 mass % or less, a static friction coefficient of the transparent conductive film is 1.00 or less, and a dynamic friction coefficient of the transparent conductive film is 0.80 or less. [3] The transparent conductive film according to [1] or [2], wherein the crystallinity of the transparent conductive film is 70% or more. [4] The transparent conductive film according to any one of [1] to [3], wherein a curable resin layer is between the transparent plastic film substrate and the transparent conductive film, and wherein a functional layer is provided on the side of the transparent plastic film substrate opposite to the side where the transparent conductive film is present. [5] The transparent conductive film according to [4], wherein the curable resin layer contains at least one type of particle selected from inorganic particles and organic particles. [6] The transparent conductive film according to [4] or [5], wherein the static friction coefficient of the functional layer is 0.70 or less and the dynamic friction coefficient of the functional layer is 0.50 or less. [7] The transparent conductive film according to any one of [4] to [6], wherein the functional layer contains at least one type of particles selected from inorganic particles and organic particles. [8] The transparent conductive film according to any one of [1] to [7], wherein an easy-adhesion layer is provided on at least one side of the transparent plastic film substrate.[9] The transparent conductive film according to any one of [4] to [7], which has an easy-adhesion layer on at least one side of the transparent plastic film substrate, and the easy-adhesion layer is disposed either between the transparent plastic film substrate and the curable resin layer or between the transparent plastic film substrate and the functional layer, or both.

[0011] According to the present invention, a transparent conductive film is provided which is excellent in all of durability against continuous input, anti-sticking properties, appearance, and silver adhesion.

[0012] Fig. 1 is a schematic side view showing one example of the transparent conductive film of the present invention. Fig. 2 is a schematic side view showing another example of the transparent conductive film of the present invention. Fig. 3 is a schematic side view showing another example of the transparent conductive film of the present invention. Fig. 4 is a schematic side view showing another example of the transparent conductive film of the present invention. Fig. 5 is a schematic view of an apparatus showing one example of the film-forming method of the present invention.

[0013] 1. Transparent Conductive Film The transparent conductive film of the present invention will be specifically described below with reference to FIGS. 1 to 4 showing examples. However, the present invention is not limited to the illustrated examples, and appropriate modifications can be made within the scope of the spirit described above and below, and all such modifications are within the technical scope of the present invention. As shown in FIG. 1 , the transparent conductive film 20 of the present invention has a structure in which a transparent conductive film 5 is laminated on at least one surface of a transparent plastic film substrate 7. Because the transparent conductive film 20 has the transparent conductive film 5 on its surface, the transparent conductive film of the present invention can be widely used in applications that utilize its conductivity, such as flat panel displays such as liquid crystal displays and electroluminescence (EL) displays, and transparent electrodes for touch panels, in electrical and electronic applications.

[0014] As shown in the transparent conductive film 20 in Figure 1, the transparent conductive film 20 of the present invention preferably has a curable resin layer 6 between the transparent plastic film substrate 7 and the transparent conductive film 5. By laminating the transparent conductive film 5 to the transparent plastic film substrate 7 via the curable resin layer 6, the curable resin layer 6 serves as a base layer for the transparent conductive film 5, and the curable resin layer 6 can block monomers and oligomers generated from the transparent plastic film substrate 7 from precipitating on the transparent conductive film 5. This improves the appearance of the transparent conductive film 20. Furthermore, by providing the curable resin layer 6, it is possible to improve the durability to continuous input and the sticking resistance.

[0015] As shown in the transparent conductive film 20 in Figure 1, the transparent conductive film 20 of the present invention preferably has a functional layer 8 on the side of the transparent plastic film substrate 7 opposite to the side on which the transparent conductive film 5 is present. The functional layer 8 can easily impart properties such as a good appearance, smooth input properties that do not catch on fingers, and resistance to scratches when inputting with a pen or the like to the transparent conductive film 20. The scratch resistance when inputting is desirably 2H or more when the pencil hardness is measured in accordance with JIS K5600-5-4:1999.

[0016] Although the curable resin layer 6 and / or the functional layer 8 are not necessarily required, providing these layers can improve the durability to continuous input, sticking resistance, appearance, etc. Furthermore, by appropriately changing the configuration of the curable resin layer 6 or the functional layer 8 (for example, the number-average particle size and content of optionally contained particles, the content of leveling agent, the thickness of each layer, etc.), it is possible to adjust the AVSa, AVSp, average protrusion width, and laminate strength of the transparent conductive film.

[0017] The transparent conductive film 20 of the present invention preferably has an easy-adhesion layer (e.g., 9A, 9B) on at least one side of the transparent plastic film substrate 7. The easy-adhesion layers (9A, 9B) serve to firmly adhere the transparent plastic film substrate 7 to the curable resin layer 6, or the transparent plastic film substrate 7 to the functional layer 8. This strong adhesion can improve continuous input durability and prevent damage to the functional layer. Furthermore, by providing a layer such as the easy-adhesion layer 9A between the transparent plastic film substrate 7 and the curable resin layer 6, the force applied in the thickness direction to the transparent conductive film 5 can be dispersed, thereby preventing cracking, peeling, wear, etc. of the transparent conductive film in a continuous input durability test.

[0018] In a more preferred embodiment, the easy-adhesion layer is disposed between the transparent plastic film substrate 7 and the curable resin layer 6 or between the transparent plastic film substrate 7 and the functional layer 8, or both. The transparent conductive film 20 of FIG. 2 has a structure in which the transparent plastic film substrate 7 and the curable resin layer 6 are laminated (adhered) via an easy-adhesion layer 9A. The transparent conductive film 20 of FIG. 3 has a structure in which the transparent plastic film substrate 7 and the functional layer 8 are laminated (adhered) via an easy-adhesion layer 9B. The transparent conductive film 20 of FIG. 4 has a structure in which the transparent plastic film substrate 7 and the curable resin layer 6 are laminated (adhered) via an easy-adhesion layer 9A, and the transparent plastic film substrate 7 and the functional layer 8 are laminated (adhered) via an easy-adhesion layer 9B. The easy-adhesion layer may or may not be in direct contact with each of the transparent plastic film substrate 7, the curable resin layer 6, and the functional layer 8.

[0019] The total light transmittance of the transparent conductive film is preferably 70% or more and 95% or less, more preferably 80% or more and 93% or less, and even more preferably 85% or more and 90% or less.

[0020] The continuous input durability of the transparent conductive film is preferably 7,500 cycles or more, more preferably 15,000 cycles or more, and even more preferably 3,000 cycles or more. The higher the continuous input durability value, the better, and there is no particular upper limit.

[0021] The transparent conductive film of the present invention has excellent anti-sticking properties, and therefore can prevent sticking between the fixed electrode and the film electrode in a resistive touch panel when the film electrode is pressed and slid with a finger, pen, etc. This allows accurate control of the touch panel input position.

[0022] The transparent conductive film of the present invention is uniform across the entire surface without unevenness. Furthermore, the average transmission image clarity of the transparent conductive film is approximately 460 to 500% (preferably approximately 470 to 500%; the higher the value, the less whitish it is, and the more preferable it is). Therefore, the transparent conductive film is clear and not whitish. The method for measuring the average transmission image clarity is described in detail in the Examples section.

[0023] <2. Transparent Conductive Film> The average arithmetic mean height (AVSa) of the transparent conductive film is 2 nm or more and 50 nm or less, preferably 3 nm or more and 30 nm or less, and more preferably 4 nm or more and 15 nm or less. By setting AVSa within the above range, a transparent conductive film with good continuous input durability, anti-sticking properties, and appearance is obtained. As AVSa increases, anti-sticking properties tend to improve, and as AVSa decreases, continuous input durability tends to improve. Furthermore, as AVSa decreases, the whitishness of the entire transparent conductive film tends to decrease, and the appearance tends to improve. AVSa has a particularly strong influence on anti-sticking properties and appearance. As AVSa increases, the contact area between the transparent conductive film and the ITO glass substrate decreases, making it difficult for them to stick together, improving anti-sticking properties, but on the other hand, the appearance becomes whitish. Therefore, AVSa is set to the above range in order to balance anti-sticking properties and appearance.

[0024] The average maximum peak height (AVSp) of the transparent conductive film is 150 nm or more and 1000 nm or less, preferably 200 nm or more and 800 nm or less, and more preferably 250 nm or more and 600 nm or less. By setting the AVSp within the above range, a transparent conductive film with good continuous input durability, anti-sticking properties, and appearance is obtained. As the AVSp increases, the anti-sticking properties tend to improve, while as the AVSp decreases, the continuous input durability tends to improve. Furthermore, as the AVSp decreases, white spots caused by protrusions on the transparent conductive film become less visible, and the appearance tends to improve. The AVSp has a particularly strong impact on continuous input durability and appearance. If the AVSp is too large, the protrusions on the transparent conductive film become tall, and the force exerted on these tall protrusions when a touch panel is subjected to a continuous input test increases, making the transparent conductive film more susceptible to damage. This means that the conductivity of the transparent conductive film deteriorates, affecting the continuous input durability. On the other hand, if AVSp is too large, the protrusions become taller, which tends to increase the width of the protrusions and make white dots more visible, leading to a deterioration in appearance. From this viewpoint, AVSp is set to the above range.

[0025] The transparent conductive film of the present invention has an average protrusion width of 12 μm or less on the surface on the transparent conductive film side and the surface opposite to the surface on which the transparent conductive film is laminated, as determined by Test Method 1 below. As a result of extensive research, the inventors have found that if the average protrusion width is within the above range, white spots caused by protrusions on the transparent conductive film surface become very difficult to see, improving the appearance. In particular, the smaller the average protrusion width, the less visible the white spots caused by protrusions on the transparent conductive film surface become, and the appearance tends to improve. The average protrusion width is preferably 0.01 μm or more and 11 μm or less, more preferably 0.03 μm or more and 10 μm or less, and even more preferably 0.05 μm or more and 9 μm or less. [Test Method 1] Particle analysis is performed using a VertScan three-dimensional surface profiler (measurement conditions: wave mode, measurement wavelength 560 nm, objective lens 50x magnification, field of view 188.709 μm × 141.496 μm) according to the following steps (i) to (v). (i) The cross-sectional area of ​​all protrusions at a height of 0.1 μm from the lowest point on the measurement surface (T ｃThis measurement is performed on both the surface on the transparent conductive film side and the surface opposite to the surface on which the transparent conductive film is laminated, and the sum of the cross-sectional areas of all the protrusions on the surface on the transparent conductive film side and the surface opposite to the surface on which the transparent conductive film is laminated is defined as the cross-sectional area of ​​all the protrusions (T ｃ (ii) The average cross-sectional area of ​​all protrusions (the total number of protrusions is N ｐ When this is done, T ｃ / N ｐ (iii) Average value (T ｃ / N ｐ ) and a protrusion having a cross-sectional area 10 times or more of the average value (T ｃ / N ｐ (iv) From the protrusions remaining in (iii), the top 20% and bottom 20% of the protrusions in order of largest cross-sectional area are further removed. (v) For the protrusions remaining in (iv), the average cross-sectional area (A) is calculated, and this value is substituted into the following formula (1) to calculate the average protrusion width (B). Formula (1): Average protrusion width (B) = 2 x (A / π) 0.5

[0026] The transparent conductive film of the present invention has a laminate strength of 450 mN / 15 mm or more as determined by Test Method 2 below. As a result of extensive research, the inventors have found that if the laminate strength of the transparent conductive film is within the above range, the transparent conductive film can be evaluated as having high adhesion to the underlying layer, making the transparent conductive film less likely to peel, thereby improving continuous input durability. A higher laminate strength is desirable for continuous input durability, and the laminate strength is preferably 500 mN / 15 mm or more, more preferably 550 mN / 15 mm or more. While there is no particular upper limit for the laminate strength, if the laminate strength is too high, the adhesive layer may be destroyed during measurement, making it difficult to accurately measure the laminate strength. The laminate strength is generally 2000 mN / 15 mm or less, and may be 1500 mN / 15 mm or less, 1000 mN / 15 mm or less, or 800 mN / 15 mm or less. Compared with the adhesion test conforming to JIS K5600-5-6:1999, which is known as a general adhesion evaluation method, the following Test Method 2 can adequately evaluate the high adhesion of a transparent conductive film, and therefore can be said to be a test more suitable for evaluating the contribution of a transparent conductive film to continuous input durability. [Test Method 2] A urethane-based two-component curing adhesive (containing 4% by weight of ethyl acetate as a solvent) is applied to the transparent conductive film side surface of the transparent conductive film using a wire bar #5, and then heated at 60°C for 1 minute. The adhesive-coated surface of the transparent conductive film and the PET surface of a PET film (thickness 100 μm) are then bonded together at 60°C using a dry lamination method (0.3 MPa, width 70 cm), and aged at 40°C for 4 days to obtain a laminate for evaluation. The resulting laminate is cut into a test piece 15 mm wide and 150 mm long, and a T-peel test is carried out at a temperature of 23° C., a relative humidity of 65%, and a peel rate of 100 mm / min to measure the maximum load.

[0027] The transparent conductive film of the present invention has a silver adhesion of 95% or more, as determined by the following Test Method A. A silver adhesion (surface area ratio of remaining silver paste) of 95% or more of the transparent conductive film can be evaluated as high adhesion between the transparent conductive film and silver. The inventors have conducted extensive research and found that by reducing the resistance of silver to peeling, changes in the contact resistance between the transparent conductive film and silver are less likely to occur even when changes in the external environment occur, such as high temperature, high humidity, or impact, and stable operation is possible when used as a resistive touch panel. The higher the silver adhesion, the better, preferably 96% or more, more preferably 97% or more, even more preferably 98% or more, even more preferably 99% or more, and particularly preferably 100%. [Test Method A] A silver paste is applied to the transparent conductive film side of the transparent conductive film to a thickness of 15 μm and heated at 150°C for 30 minutes. Next, an adhesion test is performed in accordance with JIS K5600-5-6:1999. The silver paste may be a thermosetting conductive paste containing a silver filler, and a commercially available product such as "DW-250H-5" manufactured by Toyobo Co., Ltd. The curing conditions should follow the prescription of the silver paste used, and in order to promote curing, it is also possible to adjust the curing temperature to within a range of about 30°C above the prescribed curing temperature.

[0028] The thickness of the transparent conductive film is preferably 10 nm or more and 100 nm or less, more preferably 13 nm or more and 50 nm or less, even more preferably 15 nm or more and 30 nm or less, and even more preferably 16 nm or more and 25 nm or less. When the thickness of the transparent conductive film is 10 nm or more, the entire transparent conductive film adheres to the entire transparent plastic film substrate (or the curable resin layer if a curable resin layer is laminated), stabilizing the film quality of the transparent conductive film and leading to a stable surface resistance value. It is also effective in increasing the laminate strength of the transparent conductive film. On the other hand, when the thickness of the transparent conductive film is 100 nm or less, the reflection and absorption of light by the transparent conductive film are appropriate, and the total light transmittance is at a practical level. It is also preferable from the viewpoint of productivity.

[0029] The tin oxide concentration contained in the transparent conductive film is preferably 0.5% by mass or more and 11% by mass or less, more preferably 1% by mass or more and 8% by mass or less, and even more preferably 2% by mass or more and 6% by mass or less. By containing tin oxide at 0.5% by mass or more, the surface resistance of the transparent conductive film becomes a practical level, which is preferable. Furthermore, by setting the tin oxide concentration to 11% by mass or less, the transparent conductive film becomes more likely to crystallize, thereby improving the durability to continuous input and the total light transmittance. Furthermore, a concentration within the above range is also effective in increasing the laminate strength of the transparent conductive film.

[0030] The crystallinity of the transparent conductive film is preferably 70% or more, more preferably 80% or more, and even more preferably 90% or more. If the crystallinity of the transparent conductive film is 70% or more, the abrasion resistance and laminate strength of the transparent conductive film are increased, leading to improved durability to continuous input. Furthermore, if it is within the above range, the transparency of the transparent conductive film is increased, and the total light transmittance can be improved. The higher the crystallinity, the better, with the upper limit being 100% or less.

[0031] The static friction coefficient of the transparent conductive film is preferably 1.00 or less, more preferably 0.80 or less, and even more preferably 0.50 or less. Within this range, the transparent conductive film slides well against the fixed electrode, improving anti-sticking properties. The smaller the static friction coefficient of the transparent conductive film, the better, and in consideration of inexpensive production, it is usually 0.15 or more.

[0032] The dynamic friction coefficient of the transparent conductive film is preferably 0.80 or less, more preferably 0.60 or less, and even more preferably 0.50 or less. Within this range, the transparent conductive film slides well against the fixed electrode, improving anti-sticking properties. The smaller the dynamic friction coefficient of the transparent conductive film, the better, and in consideration of inexpensive production, it is usually 0.15 or more.

[0033] The surface resistance of the transparent conductive film is preferably 50 Ω / □ or more and 900 Ω / □ or less, more preferably 60 Ω / □ or more and 700 Ω / □ or less, and even more preferably 70 Ω / □ or more and 500 Ω / □ or less. If the surface resistance is within the above range, the transparent conductive film will be of a practical level.

[0034] Although the method for forming the transparent conductive film is not particularly limited, a preferred method is, for example, to form a transparent conductive film of indium-tin composite oxide by sputtering on at least one surface of a transparent plastic film substrate 7 (hereinafter referred to as the film to be treated), on the surface of which a cured resin layer 6 may be formed. In order to produce a transparent conductive film with high productivity, it is preferable to use a so-called roll-type sputtering device in which the film to be treated is supplied from a film roll and, after film formation, is wound up into the shape of a film roll.

[0035] 5 is a schematic diagram of an example of a film formation method in a roll-type sputtering apparatus. In this illustrated example, a film to be treated 1 fed from a film roll (not shown) runs while partially contacting the surface of a center roll 2. An indium-tin sputtering target 4 is placed in a chimney 3 having an opening facing the contact point between the film to be treated 1 and the center roll 2, and a thin film of indium-tin composite oxide is deposited and laminated on the surface of the film to be treated 1 running on the center roll 2. The temperature of the center roll 2 can be controlled by a temperature regulator (not shown).

[0036] As the target, it is preferable to use a sintered target of indium-tin composite oxide. In order to improve production efficiency, a plurality of sintered targets of indium-tin composite oxide may be placed in the direction of film flow.

[0037] To form the film-forming atmosphere, it is preferable to flow oxygen gas, an inert gas (such as argon gas), or the like, using a mass flow controller as needed. Adding oxygen gas can improve the surface resistance and total light transmittance of the transparent conductive film. The flow rate ratio (volume ratio) of oxygen gas to the inert gas (oxygen gas / inert gas) is, for example, 0.005 or more, preferably 0.010 or more, more preferably 0.020 or more, and for example, 0.15 or less, preferably 0.1 or less, more preferably 0.07 or less, and even more preferably 0.05 or less. Furthermore, a hydrogen atom-containing gas (hydrogen, ammonia, a hydrogen + argon mixed gas, or the like, is not particularly limited as long as it contains hydrogen atoms, but water is excluded) may be flowed into the film-forming atmosphere as needed, using a mass flow controller.

[0038] The median value (the intermediate value between the maximum value and the minimum value) of the ratio of water pressure to inert gas in the film formation atmosphere (water pressure / inert gas partial pressure) is, for example, 7.00×10 -3 or less, preferably 5.00 x 10 -3 or less, more preferably 3.00 x 10 -3 The lower the water content in the film-forming atmosphere, the more appropriate the film quality of the transparent conductive film, the more likely it is that the surface resistance will be favorable, and the more reliable the crystallization. While it is possible to control the moisture content using the ultimate vacuum as a guide, measuring the moisture content (water pressure) during film formation is preferable for the following two reasons. First, when a film is formed on a plastic film by sputtering, the film is heated and moisture is released from the film. The ultimate vacuum does not reflect the effect of this released moisture. Second, the ultimate vacuum does not reflect the effect of moisture in the center of the roll when a film is formed on a film unwound from the film roll. When a film roll is held in a vacuum chamber, water is easily removed from the outer layer of the roll, but water is difficult to remove from the inner layer of the roll. While the film is stopped when measuring the ultimate vacuum, the film is still running during film formation, and the inner layer of the film roll, which contains a lot of water, is unwound. This increases the moisture content in the film-forming atmosphere, which is higher than the moisture content measured when the ultimate vacuum was measured. The median value of the water pressure ratio (water pressure / inert gas partial pressure) is 0.3 × 10 -3More than that is fine.

[0039] In a film roll for forming a transparent conductive film, the height difference between the most convex and most concave points on the roll end surface is preferably 10 mm or less, more preferably 8 mm or less, and even more preferably 4 mm or less. If it is 10 mm or less, water and organic components are less likely to be released from the film end surface when the film roll is placed in a sputtering device, resulting in good film quality of the transparent conductive film. The height difference may be 1 mm or more.

[0040] Before forming a transparent conductive film, it is desirable to subject the film to a bombardment process. The bombardment process involves applying a voltage to generate a discharge and generate plasma while flowing an inert gas, such as argon gas, or a mixture of a reactive gas, such as oxygen, and an inert gas. Specifically, it is desirable to bombard the film by RF sputtering using a stainless steel target or the like. The bombardment process exposes the film to plasma, releasing water and organic components from the film. This reduces the amount of water and organic components released from the film during the formation of the transparent conductive film, improving the quality of the transparent conductive film. Furthermore, the bombardment process activates the layers in contact with the transparent conductive film, improving the adhesion (lamination strength) of the transparent conductive film and further improving its durability against continuous input.

[0041] A protective film with low water absorption may be attached to the surface opposite to the surface on which the transparent conductive film is formed of the film to be treated 1. By attaching the protective film, gases such as water are less likely to be released from the film to be treated 1, improving the quality of the transparent conductive film. Examples of the base material for the protective film include olefins such as polyethylene, polypropylene, and cycloolefin.

[0042] During film formation, the film to be processed 1 is cooled to, for example, 0°C or below, preferably -5°C or below. By cooling the film to be processed 1, it is possible to suppress the release of impurities such as water and organic gases from the film, thereby ensuring appropriate film quality for the transparent conductive film. The film temperature during film formation can be substituted by the set temperature (when there are multiple set temperatures, the intermediate value between the maximum and minimum values) of a temperature regulator that adjusts the temperature of the center roll with which the running film comes into contact. The film temperature may be -20°C or above.

[0043] The sputtering apparatus is preferably equipped with an exhaust device such as a rotary pump, a turbomolecular pump, a cryopump, etc. The amount of moisture in the film formation atmosphere can be controlled by the exhaust device.

[0044] Before forming the transparent conductive film, the film for film formation can be wound into a roll. The tension when winding the film before forming the transparent conductive film is preferably 80 to 500 N / m, more preferably 90 to 400 N / m, and even more preferably 100 to 300 N / m. The lower the tension, the lower the amount of foreign matter and low-molecular-weight components adhering from the surface opposite the transparent conductive film formation surface. This improves the adhesion between the transparent conductive film and the underlying layer when the transparent conductive film is formed, suppressing peeling of the transparent conductive film and improving durability against continuous input. On the other hand, if the tension is below 80 N / m, winding slippage occurs in the film roll, making the film more susceptible to scratches. Therefore, a tension of 80 N / m or more is desirable. Furthermore, the higher the tension, the less likely winding slippage occurs, and the less likely defects such as scratches are to occur. On the other hand, if the tension exceeds 500 N / m, problems such as deformation of the roll edge of the film may occur and the laminate strength may be reduced, so the tension is preferably 500 N / m or less.

[0045] Furthermore, the tension during film transport when forming a transparent conductive film using a sputtering device is preferably 80 to 500 N / m, more preferably 90 to 400 N / m, and even more preferably 100 to 300 N / m. The lower the tension, the lower the amount of foreign matter and low-molecular-weight components adhering from the surface opposite the transparent conductive film deposition surface. This improves adhesion between the transparent conductive film and silver. On the other hand, if the tension is below 80 N / m, the film roll will slip and the film will be more susceptible to scratches. Therefore, a tension of 80 N / m or more is desirable. Furthermore, the greater the tension, the less likely it is that slippage will occur, and defects such as scratches can be suppressed. On the other hand, if the tension exceeds 500 N / m, problems such as deformation of the film roll edge may occur, or the amount of foreign matter and low-molecular-weight components adhering from the surface opposite the transparent conductive film deposition surface may increase, potentially resulting in reduced silver adhesion. Therefore, a tension of 500 N / m or less is desirable.

[0046] After forming and laminating a transparent conductive film of indium-tin composite oxide on the film to be treated, it is desirable to perform a heat treatment in an oxygen-containing atmosphere at 80°C or higher and 200°C or lower for 0.1 to 12 hours. By setting the temperature at 80°C or higher, the crystallinity of the transparent conductive film can be increased, and continuous input durability can be further improved. By setting the temperature at 200°C or lower, the flatness of the transparent plastic film can be ensured. The temperature is preferably 100°C or higher and 180°C or lower, more preferably 120°C or higher and 170°C or lower. The time is preferably 0.3 to 6 hours, more preferably 0.5 to 2 hours.

[0047] 3. Transparent Plastic Film Substrate The transparent plastic film substrate is a film obtained by melt-extruding or solution-extruding an organic polymer into a film shape, and then, if necessary, stretching the film in the longitudinal direction and / or the width direction, cooling, and heat setting. The transparent plastic film substrate may be a uniaxially oriented film or a biaxially oriented film.

[0048] Examples of the organic polymer include polyolefins such as polyethylene and polypropylene; polyesters such as polyethylene terephthalate, polyethylene-2,6-naphthalate, polypropylene terephthalate, and polybutylene terephthalate; polyamides such as nylon 6, nylon 4, nylon 66, and nylon 12; polyimide, polyamideimide, polyethersulfane, polyetheretherketone, polycarbonate, polyarylate, cellulose propionate, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyetherimide, polyphenylene sulfide, polyphenylene oxide, polystyrene, syndiotactic polystyrene, and norbornene-based polymers. Among these, polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, syndiotactic polystyrene, norbornene-based polymers, polycarbonate, and polyarylate are preferred. These organic polymers may be copolymerized with small amounts of other organic polymer monomers, or may be blended with other organic polymers.

[0049] The transparent plastic film substrate may be subjected to a surface activation treatment such as corona discharge treatment, glow discharge treatment, flame treatment, ultraviolet irradiation treatment, electron beam irradiation treatment, or ozone treatment, as long as it does not impair the object of the present invention.

[0050] The thickness of the transparent plastic film substrate is preferably 80 μm or more and 240 μm or less, more preferably 120 μm or more and 220 μm or less. The thinner the substrate, the longer the roll length of the film that can be introduced into a transparent conductive film forming device such as a roll-type sputtering device, which is preferable from the viewpoint of productivity. When the substrate is 80 μm or more in thickness, mechanical strength is maintained, so that when used in a touch panel, deformation due to input with a pen or the like is small and durability to continuous input is excellent, which is preferable. When used in a touch panel, a thickness of 240 μm or less is preferable because input can be made with light force.

[0051] <4. Curable Resin Layer> The resin constituting the curable resin layer may be any resin that can be cured by application of energy such as heating, ultraviolet irradiation, or electron beam irradiation, or by a curing agent, and examples thereof include silicone-based resins, (meth)acrylic-based resins, epoxy-based resins, melamine-based resins, polyester-based resins, and urethane-based resins. These may be used alone or in combination of two or more. From the viewpoint of productivity, it is preferable that the resin constituting the curable resin layer is an ultraviolet-curable resin.

[0052] Examples of ultraviolet-curable resins include polyfunctional (meth)acrylate resins such as acrylic acid esters or methacrylic acid esters of polyhydric alcohols, and polyfunctional urethane (meth)acrylate resins synthesized from diisocyanates, polyhydric alcohols, and hydroxyalkyl esters of acrylic acid or methacrylic acid, etc. These polyfunctional resins may be copolymerized with monofunctional monomers such as vinylpyrrolidone, methyl methacrylate, and styrene, as necessary.

[0053] The curable resin layer may contain, in addition to the resin constituting the curable resin layer described above (i.e., the resin of the main component constituting the curable resin layer), a resin that is incompatible with the resin (hereinafter, sometimes simply referred to as an incompatible resin). By dispersing the incompatible resin in the curable resin layer, appropriate unevenness can be formed on the surface of the curable resin layer, and the surface roughness can be increased over a wide area. Examples of incompatible resins include polyester-based resins, polyolefin-based resins, polystyrene-based resins, polyamide-based resins, etc.

[0054] The curable resin layer preferably further contains particles. The particles can form appropriate unevenness on the surface of the curable resin layer and the adjacent transparent conductive film. This means that the AVSa and AVSp of the transparent conductive film can be controlled within a predetermined range. When the curable resin layer contains particles, unevenness on the surface of the curable resin layer causes unevenness in the transparent conductive film. For example, in a resistive touch panel, when a transparent conductive film contacts a fixed electrode, the unevenness of the transparent conductive film creates a gap between the fixed electrode and the transparent conductive film, thereby suppressing adhesion (sticking) between the transparent conductive film and the fixed electrode. Since sticking can cause touch panel malfunctions, preventing sticking is essential in this field. Furthermore, the inclusion of particles in the curable resin layer can improve continuous input durability, anti-Newton ring properties, film winding properties, and the like.

[0055] The particles contained in the curable resin layer include at least one selected from inorganic particles and organic particles. Examples of inorganic particles include silica particles. Examples of organic particles include particles made of polyester resin, polyolefin resin, polystyrene resin, polyamide resin, acrylic resin, etc. These may be used alone or in combination of two or more.

[0056] The particles may be either monodisperse or polydisperse, with monodisperse being particularly preferred.

[0057] A preferred embodiment of the curable resin layer comprises particles (A) having a number average particle diameter of 1.0 μm or more and 6.5 μm or less. Another preferred embodiment of the curable resin layer comprises particles (B) having a number average particle diameter of 0.01 μm or more and less than 1.0 μm. Another preferred embodiment of the curable resin layer comprises particles (A) having a number average particle diameter of 1.0 μm or more and 6.5 μm or less and particles (B) having a number average particle diameter of 0.01 μm or more and less than 1.0 μm. Each of the particles (A) and the particles (B) may be used alone or in combination of two or more.

[0058] The number-average particle diameter of the particles (A) is more preferably 2.0 μm or more and 5.5 μm or less, even more preferably 2.8 μm or more and 5.0 μm or less. The number-average particle diameter of the particles (B) is more preferably 0.06 μm or more and 0.5 μm or less, even more preferably 0.1 μm or more and 0.4 μm or less. A large number-average particle diameter increases the unevenness of the transparent conductive film, resulting in increased AVSa and AVSp of the transparent conductive film, thereby improving sticking resistance. A small number-average particle diameter reduces the unevenness of the transparent conductive film, resulting in reduced AVSa and AVSp of the transparent conductive film, thereby improving continuous input durability. Furthermore, a small number-average particle diameter tends to reduce the average protrusion width. This eliminates the whitish appearance of the entire curable resin layer, making white spots caused by protrusions in the curable resin layer less visible, resulting in a good appearance.

[0059] The standard deviation of the particle diameters of the particles (A) and (B) is preferably 20% or less of the number average particle diameter, more preferably 10% or less of the number average particle diameter, and even more preferably 5% or less of the number average particle diameter. The smaller the standard deviation of the particle diameters, the more uniform the height of the irregularities in the curable resin layer, thereby achieving stable anti-sticking properties and durability against continuous input. Furthermore, uniform height of the irregularities in the curable resin layer reduces the frequency of white spots caused by protrusions on the curable resin layer, resulting in a good appearance.

[0060] The number-average particle diameter of the particles (A) is preferably slightly smaller than or equal to the thickness of the curable resin layer. By adjusting the balance between the number-average particle diameter of the particles (A) and the thickness of the curable resin layer, AVSa and AVSp can be easily controlled. The number-average particle diameter of the particles (A) is preferably 0.7 to 1.5 times, more preferably 0.8 to 1.4 times, and even more preferably 0.9 to 1.3 times the thickness of the curable resin layer. If it is 0.7 times or more, it becomes easier to form appropriate unevenness in the curable resin layer, and the winding property of the film is also improved. If it is 1.5 times or less, particle detachment can be suppressed even when a heavy load is applied. Note that if the number-average particle diameter of the particles (A) is sufficiently large relative to the thickness of the curable resin layer, AVSa, AVSp, and the average protrusion width may become too large. In this case, AVSa, AVSp, and the average projection width can be reduced by reducing the number average particle diameter of the particles (A), reducing the amount of particles (A) added, etc. On the other hand, when the number average particle diameter of the particles (A) is sufficiently small relative to the thickness of the curable resin layer, AVSa and AVSp may become too small. In this case, AVSa and AVSp can be increased by increasing the number average particle diameter of the particles (A), etc.

[0061] When the curable resin layer contains particles (A), the particles (A) are preferably contained in an amount of 0.1% by mass or more and 30% by mass or less, more preferably 2.5% by mass or more and 20% by mass or less, and even more preferably 5% by mass or more and 15% by mass or less, based on 100% by mass of the solid content constituting the curable resin layer. As the amount of particles (A) increases, the AVSa of the transparent conductive film tends to increase.

[0062] When the curable resin layer contains particles (B), the content of particles (B) is preferably 0.05% by mass or more and 25% by mass or less, more preferably 0.1% by mass or more and 22% by mass or less, and even more preferably 0.5% by mass or more and 18% by mass or less, based on 100% by mass of the solid content constituting the curable resin layer. As the amount of particles (B) increases, the unevenness of the curable resin layer increases, and as a result, AVSa and AVSp of the transparent conductive film also increase, improving the sticking resistance of the transparent conductive film.

[0063] Furthermore, when the curable resin layer contains both particles (A) and particles (B), when the total content of particles (A) and particles (B) is taken as 100 mass%, the content of particles (B) is preferably 0.1 mass% or more and 99.9 mass% or less, more preferably 20 mass% or more and 80 mass% or less, and even more preferably 30 mass% or more and 70 mass% or less.

[0064] The particles (A) may be either inorganic or organic particles, but are preferably organic particles, more preferably particles made of an acrylic resin. The particles (B) may be either inorganic or organic particles, but are preferably inorganic particles, more preferably silica particles.

[0065] The thickness of the curable resin layer is preferably 0.8 μm or more and 6.2 μm or less, more preferably 1.0 μm or more and 5.0 μm or less, and even more preferably 2.0 μm or more and 4.0 μm or less. If the thickness of the curable resin layer is 0.8 μm or more, even if the curable resin layer contains particles, sufficient protrusions can be formed while suppressing particle detachment. On the other hand, if the thickness of the curable resin layer is 6.2 μm or less, productivity is improved. Note that if the curable resin layer is thick, AVSa, AVSp, and average protrusion width tend to decrease.

[0066] The curable resin layer is formed by preparing a liquid composition for a curable resin layer containing a resin capable of forming a curable resin layer, applying the composition for a curable resin layer to an object to be laminated (e.g., a transparent plastic film substrate, an easy-adhesion layer, etc.), and then curing the resin.

[0067] The composition for the curable resin layer may contain, in addition to the resin capable of forming the curable resin layer described above, an incompatible resin, particles, a curing reaction initiator, a solvent, various known additives, and the like.

[0068] The curing reaction initiator can be selected depending on the type of curing of the resin constituting the curable resin layer, and examples thereof include radical polymerization initiators such as thermal polymerization initiators and photopolymerization initiators, various curing agents, etc., among which photopolymerization initiators are preferred. As the photopolymerization initiator, known initiators that absorb ultraviolet light and generate radicals can be used as appropriate, and examples thereof include benzoins, phenyl ketones, benzophenones, etc. The content of the curing reaction initiator is preferably 1 part by mass or more and 5 parts by mass or less per 100 parts by mass of the resin.

[0069] The solvent used in the composition for the curable resin layer is not particularly limited, and examples thereof include alcohol-based solvents such as ethyl alcohol and isopropyl alcohol; ester-based solvents such as ethyl acetate and butyl acetate; ether-based solvents such as dibutyl ether and ethylene glycol monoethyl ether; ketone-based solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; and aromatic hydrocarbon-based solvents such as toluene, xylene and solvent naphtha. These may be used alone or in combination of two or more.

[0070] A preferred example of the various additives used in the curable resin layer composition is a leveling agent. The leveling agent can suppress unevenness and defects, thereby improving the clarity of the entire curable resin layer. Furthermore, when protrusions are present in the curable resin layer, the leveling agent can suppress the spreading of the base of the protrusions, making the white spots caused by the protrusions less visible, which is preferable. The amount of leveling agent is preferably 0.01 to 0.55 parts by mass, more preferably 0.02 to 0.45 parts by mass, and even more preferably 0.03 to 0.35 parts by mass, relative to 100 parts by mass of resin. Increasing the amount of leveling agent is preferable because it makes it easier to suppress unevenness and defects, and when protrusions are present in the curable resin layer, it makes it easier to suppress the spreading of the base of the protrusions (reducing the average protrusion width). On the other hand, reducing the amount of leveling agent is expected to prevent the adhesion between the transparent conductive film and the curable resin layer from being hindered, thereby increasing the laminate strength. Furthermore, when the amount of leveling agent is reduced, the amount of low-molecular-weight components that seep out to the side of the transparent conductive film opposite the plastic film substrate is reduced, so that the adhesion between the transparent conductive film and silver is not hindered, and it is expected that the silver adhesion will be improved. Examples of leveling agents include silicone-based leveling agents, fluorine-based leveling agents, acrylic-based leveling agents, and vinyl-based leveling agents, and among these, silicone-based leveling agents are preferred. These may be used alone or in combination of two or more.

[0071] The solid content of the composition for the curable resin layer may be adjusted appropriately to obtain a viscosity appropriate for the coating method. The solid content is preferably 30% by mass or more and 75% by mass or less, more preferably 35% by mass or more and 65% by mass or less, and even more preferably 40% by mass or more and 55% by mass or less. Generally, the higher the solid content, the larger the AVSa, AVSp, and average protrusion width tend to be.

[0072] The method for coating the liquid curable resin layer composition onto the lamination target is not particularly limited, and known methods such as bar coating, gravure coating, and reverse coating can be used as appropriate. The coated curable resin layer composition is then subjected to a drying process to evaporate and remove the solvent. If an incompatible resin (e.g., polyester resin) is dissolved in the curable resin layer composition, the incompatible resin will become particles and precipitate in the composition during the drying process. After the drying process, a curable resin layer is formed by performing an appropriate treatment (e.g., ultraviolet irradiation) depending on the type of curing.

[0073] Furthermore, the surface of the laminated object to which the composition for a curable resin layer is applied may be subjected to a treatment to improve the adhesion of the curable resin layer, if necessary, before application. Examples of the treatment to improve the adhesion include a discharge treatment method in which glow or corona discharge is applied to increase carbonyl groups, carboxyl groups, and hydroxyl groups, and a chemical treatment method in which acid or alkali is used to increase polar groups such as amino groups, hydroxyl groups, and carbonyl groups.

[0074] <5. Functional Layer> The resin constituting the functional layer may be the same as the resin constituting the curable resin layer described above, and from the viewpoint of productivity, the resin constituting the functional layer is preferably an ultraviolet curable resin. Specific examples of the ultraviolet curable resin are the same as those exemplified in the section on the resin constituting the curable resin layer. In addition, the functional layer may contain an incompatible resin, as in the curable resin layer.

[0075] The functional layer preferably further contains particles, which can provide the functional layer with smooth input characteristics that do not catch on fingers and also make it easier to wind up the transparent conductive film.

[0076] The particles contained in the functional layer include at least one selected from inorganic particles and organic particles. Examples of inorganic particles include silica particles. Examples of organic particles include particles made of polyester resin, polyolefin resin, polystyrene resin, polyamide resin, acrylic resin, etc. These may be used alone or in combination of two or more. The particles contained in the functional layer and the particles contained in the curable resin layer may be of the same or different natures. Furthermore, the particles contained in the functional layer may be either monodispersed or polydispersed.

[0077] A preferred embodiment of the functional layer comprises particles (C) having a number-average particle diameter of 0.01 μm or more and 0.5 μm or less. The number-average particle diameter of particles (C) is more preferably 0.02 μm or more and 0.3 μm or less, and even more preferably 0.03 μm or more and 0.2 μm or less. If the number-average particle diameter is 0.5 μm or less, the functional layer tends to have a good appearance. If the number-average particle diameter is 0.01 μm or more, the functional layer tends to have good finger sliding properties. Particles (C) may be used alone or in combination of two or more types. Furthermore, the standard deviation of the particle diameter of particles (C) is preferably 20% or less of the number-average particle diameter, more preferably 10% or less of the number-average particle diameter, and even more preferably 5% or less of the number-average particle diameter.

[0078] When the functional layer contains particles (C), the particles (C) are preferably contained in an amount of 0.1% by mass to 50% by mass, more preferably 0.3% by mass to 30% by mass, and even more preferably 0.5% by mass to 20% by mass, based on 100% by mass of the solid content constituting the functional layer. The finger slipperiness of the transparent conductive film can be adjusted by adjusting the amount of particles (C). Furthermore, the particles (C) can form protrusions on the surface of the functional layer, making it easier to wind up the film.

[0079] The thickness of the functional layer is preferably 0.8 μm or more and 8.0 μm or less, more preferably 1.0 μm or more and 6.5 μm or less, and even more preferably 2.0 μm or more and 5.0 μm or less. If the thickness of the functional layer is 0.8 μm or more, the transparent conductive film can be provided with smooth input properties that do not catch on fingers and protection from scratches when inputting with a pen or the like. If the thickness of the functional layer is 8.0 μm or less, productivity is good.

[0080] The static friction coefficient of the functional layer is preferably 0.70 or less, more preferably 0.50 or less, even more preferably 0.40 or less, and even more preferably 0.30 or less. Within this range, the functional layer and the finger slide well, so that when the finger inputs on the touch panel, the input is smooth and free of catching. The smaller the static friction coefficient of the functional layer, the better, and in consideration of low-cost production, it is usually 0.15 or more.

[0081] The dynamic friction coefficient of the functional layer is preferably 0.50 or less, more preferably 0.40 or less, and even more preferably 0.35 or less. Within this range, the functional layer and the finger slide well, so that when the finger inputs on the touch panel, the input is smooth and free of catching. The smaller the dynamic friction coefficient of the functional layer, the better, and in consideration of low-cost production, it is usually 0.15 or more.

[0082] Similar to the curable resin layer, the functional layer is formed by preparing a liquid functional layer composition containing a resin capable of forming the functional layer, applying the functional layer composition to a laminated object (e.g., a transparent plastic film substrate, an easy-adhesion layer, etc.), and then curing the resin. In addition to the resin capable of forming the functional layer, the functional layer composition may further contain an incompatible resin, particles, a curing reaction initiator, a solvent, various known additives, etc. The curing reaction initiator, solvent, various known additives, and the method of coating the liquid functional layer composition onto the laminated object are as described for the curable resin layer. Furthermore, the surface of the laminated object to which the functional layer composition is applied may be treated to improve the adhesion of the functional layer, if necessary, before application. The adhesion improvement treatment is also as described for the curable resin layer.

[0083] The solid content of the functional layer composition may be adjusted appropriately to obtain a viscosity appropriate for the coating method, and is preferably 30% by mass or more and 75% by mass or less, more preferably 35% by mass or more and 65% by mass or less, and even more preferably 40% by mass or more and 55% by mass or less.

[0084] In an adhesion test according to JIS K5600-5-6:1999, the remaining area ratio of the functional layer is preferably 95% or more, more preferably 99% or more, and even more preferably 99.5% or more. If the remaining area ratio of the functional layer is within the above range, the transparent plastic film substrate and the functional layer are firmly adhered to each other, and even if continuous input is made with a pen, defects in appearance such as cracking, peeling, and wear of the functional layer are suppressed. Furthermore, even if a force stronger than expected is applied, cracking, peeling, and the like of the functional layer are suppressed, which is preferable.

[0085] <6. Adhesion Layer> The adhesion layer is preferably formed from a composition containing a urethane resin, a polyester resin, and a crosslinking agent. The crosslinking agent is preferably a blocked isocyanate, more preferably a trifunctional or higher functional blocked isocyanate, and even more preferably a tetrafunctional or higher functional blocked isocyanate. The thickness of the adhesion layer is, for example, 0.001 μm or more and 2.00 μm or less.

[0086] This application claims the benefit of priority based on Japanese Patent Application No. 2024-118805, filed on July 24, 2024. The entire contents of the specification of Japanese Patent Application No. 2024-118805, filed on July 24, 2024, are incorporated herein by reference.

[0087] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Various measurements and evaluations in the examples were carried out by the following methods.

[0088] 1. Measurement and Evaluation Methods (1) Number-Average Particle Diameter Three observation points were randomly selected from the cross section of each curable resin layer or functional layer of the transparent conductive film, and particles at each observation point were observed using a scanning electron microscope (Keyence Corporation, VE-8800). Fifty particles were randomly selected from each observation point and their particle diameters were measured. The particle diameters (circle-equivalent diameters) of the 50 observed particles were then divided into 0.020 μm intervals, and the total number of particles contained in each interval was calculated. A histogram was created with the number of particles on the vertical axis and particle diameters on the horizontal axis in 0.020 μm intervals. For particles with a particle diameter within ±30% of the absolute value of the center value of the particle diameter interval where the peak of the normal distribution was the maximum, the number average of the observed particle diameters was taken as the average particle diameter. For example, if the histogram has two peaks of the normal distribution, this indicates that two types of particles were added, and the average particle diameters of the two types were calculated using the same method as above. The average particle diameters at three locations in the curable resin layer were further averaged to obtain the number average particle diameter of the curable resin layer, and the average particle diameters at three locations in the functional layer were further averaged to obtain the number average particle diameter of the functional layer.

[0089] (2) Thickness of the Curable Resin Layer and the Functional Layer The thickness of each layer was determined by observing the cross section of the transparent conductive film at any five points (magnification: 5000x) using a scanning electron microscope (VE-8800, manufactured by Keyence Corporation), and the average value of the thicknesses measured at the five points was taken as the thickness of each layer.

[0090] (3) Coefficient of static friction and coefficient of dynamic friction The coefficient of static friction and coefficient of dynamic friction of the transparent conductive film surface and the functional layer surface of the transparent conductive film were evaluated according to JIS C2151 under the following conditions: the size of the test piece was 70 mm wide x 200 mm long, the test speed was 200 mm / min, the weight of the sliding piece was 4.4 kg, and the area of ​​contact between the sliding piece and the transparent conductive film surface or the functional layer surface was 5000 mm 2 It was.

[0091] (4) Transparent Conductive Film Thickness: A film sample piece laminated with a transparent conductive film was cut to a size of 1 mm x 10 mm and embedded in an epoxy resin for electron microscopy. The epoxy resin consisted of the base resin (trade name "Epon 812"; Nacalai Tesque, Inc.), the curing agent (trade name "MNA"; Nacalai Tesque, Inc.), and the accelerator (trade name "DNP-30"; Nacalai Tesque, Inc.), mixed in a volume ratio of base resin:curing agent:accelerator = 100:89:1.5 and cured at 60 °C for 12 hours. The sample piece encapsulated in the epoxy resin was fixed to the sample holder of an ultramicrotome, and a cross-sectional thin section parallel to the short side of the embedded sample piece was prepared. Next, a portion of the thin film of this section that was not significantly damaged was photographed using a transmission electron microscope (JEOL, JEM-2010) at an accelerating voltage of 200 kV, a bright field, and a magnification of 10,000 times. The film thickness was determined from the photograph obtained.

[0092] (5) Tin oxide concentration in the transparent conductive film. Cut a piece of the transparent conductive film (approximately 15 cm 2 ) was placed in a quartz Erlenmeyer flask, 20 ml of 6 mol / L hydrochloric acid was added, and the flask was sealed with film to prevent the acid from volatilizing. The flask was left at room temperature for 9 days with occasional shaking to dissolve the transparent conductive film. The remaining film was removed, and the hydrochloric acid in which the transparent conductive film had dissolved was used as the measurement solution. In and Sn in the solution were determined by the calibration curve method using an ICP optical emission analyzer (manufacturer: Rigaku, model: CIROS-120 EOP). A wavelength with high sensitivity and no interference was selected for the measurement wavelength of each element. Furthermore, commercially available standard solutions of In and Sn were diluted and used as standard solutions.

[0093] (6) Crystallinity of the Transparent Conductive Film: A transparent conductive film sample piece laminated with the transparent conductive film was cut to a size of 1 mm x 10 mm and attached to the top surface of a suitable resin block with the transparent conductive film surface facing outward. The resin block was composed of a base resin (trade name "Epon 812"; Nacalai Tesque, Inc.), a curing agent (trade name "MNA"; Nacalai Tesque, Inc.), and an accelerator (trade name "DNP-30"; Nacalai Tesque, Inc.), mixed in a volume ratio of base resin:curing agent:accelerator = 100:89:1.5, and cured at 60°C for 12 hours. The sample piece attached to the resin block was trimmed, and then ultrathin sections approximately parallel to the film surface were prepared using a standard ultramicrotome technique. The sections were observed under a transmission electron microscope (JEOL, JEM-2010) to select a surface portion of the conductive thin film that was not significantly damaged, and photographed at an accelerating voltage of 200 kV and a direct magnification of 40,000x. The crystallinity of the transparent conductive film was evaluated by observing the proportion of crystal grains under a transmission electron microscope, that is, the degree of crystallinity.

[0094] (7) Surface Resistance: Measured by a four-terminal method in accordance with JIS K7194:1994. The measuring instrument used was Lotesta AX MCP-T370 manufactured by Mitsubishi Chemical Analytech Co., Ltd.

[0095] (8) Adhesion test of the functional layer The adhesion test of the functional layer was carried out in accordance with JIS K5600-5-6:1999. The test results of adhesion are shown as a residual area ratio (%). The maximum residual area ratio (%) is 100%, and the closer the residual area ratio is to 100%, the smaller the peeled area.

[0096] (9) Average arithmetic mean height (AVSa) and average maximum peak height (AVSp) Five measurement points were selected from the transparent conductive film surface of the transparent conductive film, and the arithmetic mean height (Sa) and the maximum peak height (Sp) (ISO; surface roughness) were measured at each measurement point. The arithmetic mean values ​​of the five points were then evaluated as the average arithmetic mean height (AVSa) and the average maximum peak height (AVSp), respectively. The five points were selected as follows: First, an arbitrary point (K) was selected. Next, in the longitudinal (MD) direction of the film, two points were selected, one point each 5 cm upstream and downstream of point (K) as the center. Next, in the transverse (TD) direction of the film, two points were selected, one point each 5 cm left and right of point (K) as the center. For the measurements, the arithmetic mean height (Sa) and maximum peak height (Sp) (ISO; surface roughness) were determined using a three-dimensional surface profiler, Vertscan (R5500H-M100, manufactured by Ryoka Systems Co., Ltd. (measurement conditions: wave mode, measurement wavelength: 560 nm, objective lens: 10x magnification when measuring AVSa, and objective lens: 110x magnification when measuring AVSp)) in accordance with ISO 25178. Values ​​less than 1 nm were rounded off.

[0097] (10) Average Protrusion Width The average protrusion width is determined by the following Test Method 1. [Test Method 1] Particle analysis is performed using a three-dimensional surface profiler, Vertscan (R5500H-M100, manufactured by Ryoka Systems Co., Ltd., measurement conditions: wave mode, measurement wavelength 560 nm, objective lens 50x, field of view 188.709 μm × 141.496 μm), according to the following steps (i) to (v): (i) The cross-sectional area (T ｃ This measurement is performed on both the surface on the transparent conductive film side and the surface opposite to the surface on which the transparent conductive film is laminated, and the sum of the cross-sectional areas of all the protrusions on the surface on the transparent conductive film side and the surface opposite to the surface on which the transparent conductive film is laminated is defined as the cross-sectional area of ​​all the protrusions (T ｃ (ii) The average cross-sectional area of ​​all protrusions (the total number of protrusions is N ｐ When this is done, T ｃ / N ｐ (iii) Average value (T ｃ / N ｐ ) and a protrusion having a cross-sectional area 10 times or more of the average value (T ｃ / N ｐ(iv) From the protrusions remaining in (iii), the top 20% and bottom 20% of the protrusions in order of largest cross-sectional area are further removed. (v) For the protrusions remaining in (iv), the average cross-sectional area (A) is calculated, and this value is substituted into the following formula (1) to calculate the average protrusion width (B). Formula (1): Average protrusion width (B) = 2 x (A / π) 0.5

[0098] (11) Lamination Strength of Transparent Conductive Film The laminate strength of a transparent conductive film is determined by the following Test Method 2. [Test Method 2] A urethane-based two-component curing adhesive (containing 4% by mass of ethyl acetate as a solvent; a mixture of Takelac (registered trademark) A525S (manufactured by Mitsui Chemicals, Inc.), Takenate (registered trademark) A50 (manufactured by Mitsui Chemicals, Inc.), and ethyl acetate (Nacalai Tesque, Inc.) in a mass ratio of 13.5:8.2:1) is applied to the transparent conductive film surface on the transparent conductive film side using a wire bar #5, and then heated at 60°C for 1 minute. The adhesive-coated surface of the transparent conductive film was then bonded to the PET surface (the flat surface out of the uneven surface and the flat surface) of a PET film (Cosmoshine (registered trademark) A4160, manufactured by Toyobo Co., Ltd., thickness 100 μm) using a dry lamination method (0.3 MPa, width 70 cm) at 60 ° C., and aged at 40 ° C. for 4 days to obtain a laminate for evaluation. The thickness of the adhesive layer formed from the urethane-based two-component curing adhesive after drying was approximately 4 μm. The obtained laminate was cut into a width of 15 mm and a length of 150 mm to prepare a test piece. A T-peel test was performed using an autograph (Shimadzu Corporation's "Autograph AG-X") at a temperature of 23 ° C., a relative humidity of 65%, and a peel rate of 100 mm / min, and the maximum load was measured.

[0099] (12) Continuous Input Durability The continuous input durability of the transparent conductive film was evaluated by the following Test Method 3. [Test Method 3] A glass substrate (size: 60 mm x 50 mm) was placed in a sputtering device, and then 1.5 x 10 -4 The chamber was evacuated to a vacuum of 3 W / cm. Next, oxygen was introduced to 10 mPa, and then argon was introduced to bring the total pressure to 0.6 Pa. An indium-tin composite oxide sintered target (tin oxide content: 10 mass%, manufactured by Mitsui Mining & Smelting Co., Ltd.) was used. 2A 20 nm thick indium-tin composite oxide conductive film (tin oxide content: 10% by mass) was formed on one side of the glass substrate by DC magnetron sputtering. Starting from one of the four corners of the ITO glass substrate, a square frame (inner 38 mm x 38 mm) was formed. Specifically, three sheets of double-sided tape (product name "Kiku Double Tape No. 192T", manufactured by Kikusui Tape Co., Ltd., thickness 35 μm, width 6 mm) were attached to the conductive film side, and an adhesive square frame with a thickness of 105 μm and an inner circumference of 38 mm x 38 mm was formed with the attached double-sided tape. A transparent conductive film (size: 60 mm x 50 mm) was attached without tension to the square frame (double-sided tape) attached to the ITO glass substrate, with the conductive films facing each other, to create an evaluation panel. At this time, the transparent conductive film was allowed to protrude beyond the ITO glass substrate. The ITO glass substrate and transparent conductive film of the obtained evaluation panel were connected with a constant voltage power supply, and 5 V was applied. Next, a load of 2.5 N was applied to a polyacetal pen (trade name "TPS (registered trademark) POM (NC)" manufactured by Toray Plastics Precision Co., Ltd., tip shape: 0.8 mmR) and an area sliding test was performed on the touch panel a set number of times. The area sliding test consisted of a set number of linear slides, a sliding distance of 30 mm, a sliding speed of 180 mm / sec, and 11 parallel linear slides spaced 0.5 mm apart. The sliding location was near the center of the evaluation panel. After the area sliding test, the constant voltage power supply was turned off, and the ITO glass substrate and transparent conductive film of the evaluation panel were connected with a tester. Next, the resistance value was measured when pressing the center of the area sliding portion with a load of 0.5 N using silicone rubber (JIS K6253 durometer type A hardness 30°, tip shape: 120 mmR). If the resistance value at this time is 4 kΩ or less, the area sliding test is deemed to have passed the set number of times. Thereafter, the set number of times of the area sliding test is increased and measurements are continued, and the maximum set number of times of the area sliding test at which the resistance value is 4 kΩ or less is evaluated as the continuous input durability of the transparent conductive film.

[0100] (13) Anti-sticking property The anti-sticking property of the transparent conductive film was evaluated by the following test method 4. [Test method 4] A pseudo-resistive touch panel was fabricated using the transparent conductive film. Specifically, a glass substrate (size: 232 mm × 151 mm) was first placed in a sputtering device, and then a 1.5 × 10 -4 The chamber was evacuated to a vacuum of 3 W / cm. Next, oxygen was introduced to 10 mPa, and then argon was introduced to bring the total pressure to 0.6 Pa. An indium-tin composite oxide sintered target (tin oxide content: 10 mass%, manufactured by Mitsui Mining & Smelting Co., Ltd.) was used. 2A 20 nm thick indium-tin composite oxide conductive film (tin oxide content: 10% by mass) was formed on one side of a glass substrate by DC magnetron sputtering. Next, dot spacers (circular (30 μm length × 30 μm width) × 4 μm height) made of UV-curable resin (product name "CR-103C-1" manufactured by Toyobo Co., Ltd.) were formed on the surface of the conductive film at a 4 mm pitch in a square lattice pattern to produce an ITO glass substrate. A rectangular frame (inner: 190 mm × 135 mm) was formed starting from one of the four corners of the resulting ITO glass substrate. Specifically, double-sided tape (product name "#741" cut to a predetermined size, manufactured by Ebisu Chemical Industry Co., Ltd., thickness 105 μm, width 6 mm) was attached to the conductive film side, and an adhesive rectangular frame with a thickness of 105 μm and an inner circumference of 190 mm × 135 mm was formed with the attached double-sided tape. A transparent conductive film (size: 220 mm x 135 mm) was attached to a rectangular frame (double-sided tape) attached to an ITO glass substrate without tension, with the conductive films facing each other. One short side of the transparent conductive film was allowed to extend beyond the ITO glass substrate. Next, a polyacetal pen (trade name "TPS (registered trademark) POM (NC)" manufactured by Toray Plastics Precision Co., Ltd., tip shape: 0.8 mmR) was held in hand and rubbed 10 times in a straight line over a distance of approximately 100 mm at a load of approximately 200 g and a speed of approximately 10 cm / sec. The sound of the rub was recorded. If only the sound of the pen rubbing against the transparent conductive film was heard, the anti-sticking performance was evaluated as OK. If, in addition to the sound of the pen rubbing against the transparent conductive film, another sound (e.g., a high-pitched clicking sound) was heard between the transparent conductive film and the ITO glass, the anti-sticking performance was evaluated as NG. This test utilizes the phenomenon that when a transparent conductive film and ITO glass are attached, sound is generated between them.Whether or not any other sounds are generated besides the sound of the pen rubbing against the transparent conductive film can be determined by comparing the sound made when a pen is similarly slid across a separately prepared transparent conductive film that is not attached to ITO glass.

[0101] (14) Appearance The appearance of the transparent conductive film was evaluated using Test Method 5 below. [Test Method 5] The appearance of the transparent conductive film was evaluated by placing the transparent conductive film under a three-wavelength fluorescent lamp. The evaluation was based on the following three criteria. The first criteria was the evaluation of the uniformity of the entire surface of the transparent conductive film. In the evaluation of transmission image clarity described below, the sum of the transmission image clarity at any five points and the average value (Ac) of the sum of the transmission image clarity were calculated. If the sum of the transmission image clarity at each of the five points was all within ±20% of the average value (Ac) of the sum of the transmission image clarity, the entire surface was evaluated as uniform (OK). If even one of the sums of the transmission image clarity at each of the five points exceeded ±20% of the average value (Ac) of the sum of the transmission image clarity, the entire surface was evaluated as not uniform (NG). The second criteria was the visual confirmation of the presence or absence of white spots on the transparent conductive film. If there were no white spots, the film was evaluated as OK, and if there were white spots, the film was evaluated as NG. Usually, if the average protrusion width is 12 μm or less, it is difficult to visually confirm white spots. The third point is the evaluation of the transmitted image clarity of the transparent conductive film. First, in accordance with JIS K7374, the transmitted image clarity was measured using an image clarity measuring device using five types of optical combs with widths of 0.125 mm, 0.25 mm, 0.5 mm, 1 mm, and 2 mm, and the sum of the transmitted image clarity measured using the five types of optical combs was calculated. Similarly, the transmitted image clarity was measured at any five points, and the sum of the transmitted image clarity at each point was calculated. The sum of the transmitted image clarity at the five points obtained was added up and divided by 5 to calculate the average value (Ac) of the sum of the transmitted image clarity. A sample was deemed to have passed when the average value (Ac) of the sum of the transmitted image clarity was 460% or more.

[0102] (15) Total Light Transmittance The total light transmittance of the transparent conductive film was measured in accordance with JIS K7361-1:1997 using NDH-2000 manufactured by Nippon Denshoku Industries Co., Ltd.

[0103] (16) Adhesion of Silver The adhesion of silver to the transparent conductive film was evaluated by the following Test Method A. As in the "Functional Layer Adhesion Test," the test results for adhesion are expressed as a remaining area ratio (%). [Test Method A] A silver paste ("DW-250H-5" manufactured by Toyobo Co., Ltd., curing method: heat curing, filler: silver, viscosity: 270 dPa s / 25°C, specific resistance: 3.5 × 10) was applied to the transparent conductive layer side of the transparent conductive film. -5The coating is applied to a thickness of 15 μm and heated at 150° C. for 30 minutes. Next, an adhesion test is carried out in accordance with JIS K5600-5-6:1999.

[0104] 2. In the column of laminate film examples, the following laminate films were used, each comprising a transparent plastic film substrate, a curable resin layer, and a functional layer.

[0105] (1) Substrates Substrate 1 (transparent plastic film substrate): biaxially oriented transparent PET film having easy-adhesion layers on both sides (manufactured by Toyobo Co., Ltd., COSMOSHINE (registered trademark) A4380, thickness shown in Table 1) Substrate 2 (transparent plastic film substrate): biaxially oriented transparent PET film having easy-adhesion layers on one side and not on the other side (manufactured by Toyobo Co., Ltd., COSMOSHINE (registered trademark) A4180, thickness shown in Table 1) Substrate 3 (transparent plastic film substrate): biaxially oriented PET film having easy-adhesion layers on both sides (manufactured by Toyobo Co., Ltd., COSMOSHINE (registered trademark) A4180, the easy-adhesion layers of which were removed by wiping with Bemcot (registered trademark, manufactured by Asahi Kasei Corporation) soaked in methyl ethyl ketone, thickness shown in Table 1)

[0106]

[0107] (2) Curable Resin Layer: 100 parts by mass of a photopolymerization initiator-containing acrylic resin (Seikabeam (registered trademark) EXF-01J, manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.) were blended with particles (particles A, particles B) having the number-average particle size shown in Table 2 and a leveling agent (silicone-based leveling agent, DOWSIL (registered trademark) 57 Additive, manufactured by The Dow Chemical Company) in the amounts shown in Table 2. Particles A are monodispersed acrylic particles or polydispersed acrylic particles, and particles B are monodispersed silica particles. In Table 2, the leveling agent concentration refers to the concentration relative to 100 parts by mass of the resin. Thereafter, a mixed solvent of toluene / methyl ethyl ketone (MEK) (8 / 2: mass ratio) was added so that the solids concentration was the value shown in Table 2, and the mixture was stirred to dissolve uniformly, thereby preparing a coating solution (Coating Solution A). Coating Solution A, adjusted to a coating thickness of the value shown in Table 2, was applied to one side of a transparent plastic film substrate using a Meyer bar. After drying at 80°C for 1 minute, the coating was irradiated with ultraviolet light (light intensity: 300 mJ / cm) using an ultraviolet irradiation device (manufactured by Eye Graphics, UB042-5AM-W type). 2 ) and the coating was cured.

[0108]

[0109] (3) Functional Layer: 100 parts by mass of a photopolymerization initiator-containing acrylic resin (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd., Seikabeam (registered trademark) EXF-01J) was blended with particles (particles C) having a number average particle size shown in Table 3 and a leveling agent (silicone-based leveling agent, manufactured by The Dow Chemical Company, DOWSIL (registered trademark) 57 Additive) in the amounts shown in Table 3. In Table 3, the leveling agent concentration refers to the concentration relative to 100 parts by mass of the resin. A mixed solvent of toluene / MEK (8 / 2: mass ratio) was then added so that the solids concentration was the value shown in Table 3, and the mixture was stirred and dissolved uniformly to prepare a coating solution (Coating Solution C). Coating Solution C, adjusted to a coating thickness of the value shown in Table 3, was applied to the surface of a transparent plastic film substrate opposite the curable resin layer using a Meyer bar. After drying at 80°C for 1 minute, the coating was irradiated with ultraviolet light (light intensity: 300 mJ / cm) using an ultraviolet irradiation device (manufactured by Eye Graphics, UB042-5AM-W type). 2 ) and the coating was cured.

[0110]

[0111] Examples 1 to 7 The laminated film wound at the tension shown in Table 4 was placed in a vacuum chamber and -4 The chamber was evacuated to a vacuum of 0.6 Pa. Next, oxygen was introduced, followed by argon, until the total pressure reached 0.6 Pa. The flow rate ratio of oxygen to argon is shown in Table 4.

[0112] As shown in Figure 5, a transparent conductive film was formed by sputtering from a target 4 in a chimney 3 onto a curable resin layer of a laminated film (film to be treated) 1 on a center roll 2. A sintered target of indium-tin composite oxide (the tin oxide concentration is shown in Table 4, the remainder being indium oxide) was used as the target 4, and the sputtering power was 3 W / cm 2 A transparent conductive film was formed by DC magnetron sputtering at 1000 W / cm . The film thickness was controlled by changing the speed at which the laminated film (film to be treated) 1 passed over the target 4. The tension during film transport when forming the transparent conductive film was set to the conditions shown in Table 4. The ratio of water vapor pressure to argon in the film-forming atmosphere during sputtering was measured using a gas analyzer (Transpector XPR, manufactured by Inficon), and the results are shown in Table 4. As shown in Table 4, the water vapor pressure ratio was adjusted by adjusting the presence or absence of a bombardment process, the presence or absence of a protective film, the unevenness of the film roll end surface, the temperature of the heating medium in the temperature controller that controls the temperature of the center roll in contact with the film. In the bombardment process, SUS (stainless steel) was used as the target, and the temperature was 0.5 W / cm . 2RF sputtering was performed at 1000 K. The amount of gas introduced during RF sputtering was the same as the amount of gas introduced into the vacuum apparatus described in the Examples. When a protective film was used, a 65 μm thick polyethylene film was used as the protective film. An acrylic adhesive was applied to one side of the protective film, and the protective film was attached to the side of the laminated film opposite to the side on which the transparent conductive film was formed. The temperature of the heating medium was calculated as the temperature exactly halfway between the maximum and minimum temperatures from the start to the end of film formation on the film roll, and is shown in Table 4. The film laminated with the transparent conductive film was subjected to the heat treatment shown in Table 4 to obtain a transparent conductive film. The properties of the obtained transparent conductive film are shown in Table 5.

[0113] Comparative Examples 1 to 8 Transparent conductive films were prepared in the same manner as in Examples 1 to 7, except that laminate films prepared under the conditions shown in Tables 1 to 3 were used and transparent conductive films were formed under the conditions shown in Table 4. In Comparative Example 7, a sintered target of indium oxide containing no tin oxide was used as target 4 instead of the sintered target of indium-tin composite oxide. The properties of the resulting transparent conductive films are shown in Table 5. In Comparative Example 5, winding misalignment occurred in the film roll before the transparent conductive film was formed, resulting in scratches on the film. In Comparative Example 6, unevenness and white spots due to oligomer precipitation were observed, and winding misalignment occurred in the transparent conductive film roll, resulting in scratches on the film. The reason for the poor uniformity evaluation in Comparative Example 8 is presumed to be that the absence of an easy-adhesion layer on the functional layer side and the small amount of leveling agent in the functional layer made it difficult for the coating liquid for the functional layer to wet the transparent plastic film substrate.

[0114] In Table 4, "*1" means that the test piece fell over and measurement was not possible.

[0115]

[0116]

[0117] Transparent conductive films can be widely used in electrical and electronic applications, such as flat panel displays such as liquid crystal displays and electroluminescence (EL) displays, and transparent electrodes for touch panels.

[0118] REFERENCE SIGNS LIST 1 film to be treated 2 center roll 3 chimney 4 target 5 transparent conductive film 6 curable resin layer 7 transparent plastic film substrate 8 functional layer 9A easy-adhesion layer 9B easy-adhesion layer 20 transparent conductive film

Claims

1. A transparent conductive film comprising a transparent conductive film of indium-tin composite oxide laminated on at least one surface of a transparent plastic film substrate, wherein the average arithmetic mean height (AVSa) of the transparent conductive film is 2 nm or more and 50 nm or less, the average maximum peak height (AVSp) of the transparent conductive film is 150 nm or more and 1000 nm or less, the average protrusion widths of the surface on the transparent conductive film side and the surface opposite to the surface on which the transparent conductive film is laminated, as determined by Test Method 1 below, are 12 μm or less, the laminate strength of the transparent conductive film is 450 mN / 15 mm or more as determined by Test Method 2 below, and the silver adhesion of the transparent conductive film, as determined by Test Method A below, is 95% or more. [Test Method 1] Particle analysis is performed using a three-dimensional surface profiler, VertScan (measurement conditions: wave mode, measurement wavelength 560 nm, objective lens 50x, field of view 188.709 μm × 141.496 μm) in the following steps (i) to (v). (i) The cross-sectional area (T ｃ This measurement is performed on both the surface on the transparent conductive film side and the surface opposite to the surface on which the transparent conductive film is laminated, and the sum of the cross-sectional areas of all the protrusions on the surface on the transparent conductive film side and the surface opposite to the surface on which the transparent conductive film is laminated is defined as the cross-sectional area of ​​all the protrusions (T ｃ (ii) The average cross-sectional area of ​​all protrusions (the total number of protrusions is N ｐ When this is done, T ｃ / N ｐ (iii) Average value (T ｃ / N ｐ ) and a protrusion having a cross-sectional area 10 times or more of the average value (T ｃ / N ｐ (iv) From the protrusions remaining in (iii), the top 20% and bottom 20% of the protrusions in order of largest cross-sectional area are further removed. (v) For the protrusions remaining in (iv), the average cross-sectional area (A) is calculated, and this value is substituted into the following formula (1) to calculate the average protrusion width (B). Formula (1): Average protrusion width (B) = 2 x (A / π) 0.5 [Test Method 2] A urethane-based two-component curing adhesive (containing 4% by weight of ethyl acetate as a solvent) is applied to the transparent conductive film side surface using a wire bar #5, and then heated at 60°C for 1 minute. The adhesive-coated surface of the transparent conductive film is then bonded to the PET surface of a 100 μm thick PET film using a dry lamination method (0.3 MPa, width 70 cm) at 60°C, and aged at 40°C for 4 days to obtain a laminate for evaluation. The resulting laminate is cut into a width of 15 mm and a length of 150 mm to prepare a test piece. A T-peel test is performed at a temperature of 23°C, a relative humidity of 65%, and a peel rate of 100 mm / min to measure the maximum load. [Test Method A] A silver paste is applied to the transparent conductive film side to a thickness of 15 μm and heated at 150°C for 30 minutes. Next, an adhesion test is carried out in accordance with JIS K5600-5-6:1999.

2. The transparent conductive film according to claim 1, wherein the transparent conductive film has a thickness of 10 nm or more and 100 nm or less, a tin oxide concentration of 0.5 mass % or more and 11 mass % or less, a static friction coefficient of 1.00 or less, and a dynamic friction coefficient of 0.80 or less.

3. The transparent conductive film according to claim 1 or 2, wherein the crystallinity of the transparent conductive film is 70% or more.

4. The transparent conductive film according to claim 1 or 2, which has a curable resin layer between the transparent plastic film substrate and the transparent conductive film, and which has a functional layer on the side of the transparent plastic film substrate opposite to the side on which the transparent conductive film is present.

5. The transparent conductive film according to claim 4, wherein the curable resin layer contains at least one type of particles selected from inorganic particles and organic particles.

6. The transparent conductive film according to claim 4, wherein the static friction coefficient of the functional layer is 0.70 or less and the dynamic friction coefficient of the functional layer is 0.50 or less.

7. The transparent conductive film according to claim 4, wherein the functional layer contains at least one type of particles selected from inorganic particles and organic particles.

8. The transparent conductive film according to claim 1 or 2, which has an easy-adhesion layer on at least one side of the transparent plastic film substrate.

9. The transparent conductive film according to claim 4, which has an easy-adhesion layer on at least one side of the transparent plastic film substrate, and the easy-adhesion layer is disposed either between the transparent plastic film substrate and the curable resin layer or between the transparent plastic film substrate and the functional layer, or both.

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