Transparent conductive thin film

Abstract

The objective is to provide a transparent conductive film with excellent adaptability to input strength and input stability. The transparent conductive film of this invention is a transparent conductive film having at least one area layer of indium-tin composite oxide on a transparent plastic film substrate. The input initial load is greater than 15g and less than 25g, and the voltage drop time is more than 0.00 ms and less than 0.40 ms. Preferably, the film stiffness (BR) is more than 0.38 N·cm and less than 0.90 N·cm, and the average of the maximum peak height Sp of the conductive surface (AVSp) satisfies the following formula (2-1). 4.7×BR-3.6≦AVSp<4.7×BR-1.8... Equation (2-1) (Where, BR-based film stiffness / softness (N·cm), AVSp-based average maximum peak height (μm))

Description

Technical Field

[0001] This invention relates to a transparent conductive film having an indium-tin composite oxide transparent conductive film deposited on a transparent plastic film substrate. Prior Technology

[0002] Transparent conductive films, which have a transparent and low-resistance thin film deposited on a transparent plastic substrate, are widely used in applications that utilize their conductivity. For example, they are widely used in the electrical and electronic fields as transparent electrodes for flat panel displays such as liquid crystal displays and electroluminescent (EL) displays, and touch panels.

[0003] A resistive touch panel combines a fixed electrode with a transparent conductive film coated on a glass or plastic substrate, and a movable electrode (also called a thin-film electrode) with a transparent conductive film coated on a plastic film. These are then overlapped on top of a display. When a finger or stylus presses the thin-film electrode (called input), the transparent conductive films of the fixed electrode and the thin-film electrode come into contact, thus identifying the input location.

[0004] Patent document 1 discloses a transparent conductive laminate for touch panels, which is formed by a transparent conductive film comprising at least one area layer of a polymer film substantially mainly composed of crystalline indium oxide. The durability of the notebook is improved by crystallizing the indium oxide. [Previous Technical Documents] [Patent Literature]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2004-071171 Summary of the Invention

[0006] [The problem the invention aims to solve]

[0007] Regarding touch panels, the requirement is that even with continuous pen input, the transparent conductive film will not crack, peel, or wear (pen sliding durability). Furthermore, regarding touch panels, a suitable range of input intensity (suitable input intensity) is required. For example, when pressing the thin-film electrodes with a finger or pen to bring the transparent conductive film of the fixed electrode and the thin-film electrode into contact, there are instances where the touch panel is accidentally touched by hand or sleeve, or when hesitating about where to touch, the touch panel is accidentally touched by pen or other means. Ideally, input caused by such accidental contact with the touch panel should be minimized (error input prevention). However, if error input prevention is increased, there is a tendency to decrease comfortable input. Comfortable input refers to the ability to input with a pen or finger on a resistive film touch panel without consciously applying pressure. A balance between error input prevention and comfortable input is required.

[0008] In addition, regarding the touch panel, excellent input stability is required, meaning that the input to the touch panel is stable from the moment the pen touches it until it is removed. For example, it is required to reduce text blurring that occurs during continuous text input (fast writing performance) and to prevent the stroke portion of the characters from becoming blurred (stroke input performance). In the technology of Patent Document 1, pen glide durability cannot be improved without crystallizing indium oxide. Furthermore, existing transparent conductive film systems, including those in Patent Document 1, are also insufficient in terms of input strength (error prevention, comfortable input) and input stability (fast writing, stroke input).

[0009] Therefore, the object of the present invention is to provide a transparent conductive film with excellent adaptability to input strength and input stability. Furthermore, a preferred object of the present invention is to provide a transparent conductive film with further pen-slip durability. [Methods used to solve problems]

[0010] The present invention is an invention made in view of the above-described situation, and the transparent conductive film of the present invention, which is able to solve the above-described problems, comprises the following structure. [1] A transparent conductive film, comprising a transparent conductive film having at least one area layer of indium-tin composite oxide on a transparent plastic film substrate. The initial input load coefficient determined by test method 1 is greater than 15g and less than 25g. The voltage drop time obtained by test method 2 is greater than 0.00 milliseconds and less than 0.40 milliseconds. [Experimental Method 1] An indium-tin composite oxide conductive film (tin oxide content: 10% by mass) with a thickness of 20 nm is formed on one side of a glass substrate. On the surface of this film, epoxy resin dot-shaped interstices (60 μm x 60 μm x 5 μm) are formed into a square grid with a spacing of 4 mm to serve as a panel. On the conductive film side of this panel, an adhesive rectangular frame with a thickness of 105 μm and an inner circumference of 190 mm x 135 mm is sandwiched between them. Meanwhile, a transparent conductive film is superimposed with the conductive films facing each other to create an evaluation panel. From the transparent conductive film side of this evaluation panel, a polyacetal pen with a hemispherical tip of 0.8 mm radius is continuously pressed at the center of the 4-dot grid of the dot-shaped interstices. The pressure at which the resistance value begins to stabilize is set as the input start load. [Experimental Method 2] Connect the aforementioned evaluation panel to a constant voltage power supply of 6V. Using a pen with a hemispherical tip and a radius of 0.8mm, apply a load of 50gf and press the center of the four-point grid of the dotted spacer at intervals of 5 times per second from the transparent conductive film side. The time from when the voltage begins to decrease from 6V when the pen leaves the transparent conductive film is taken as the starting point, until the voltage reaches 5V, and this time is defined as the voltage loss time. [2] As in [1], the transparent conductive film, wherein the stiffness (BR) of the film determined by test method 3 is above 0.38 N·cm and below 0.90 N·cm. The average (AVSp) of the maximum peak height Sp of the conductive surface obtained by test method 4 satisfies the following equations (2-1) and (2-2). The contact area ratio (CA) obtained by test method 5 satisfies the following equation (2-3). 4.7×BR-3.6≦AVSp<4.7×BR-1.8...Equation (2-1) 0.005≦AVSp≦12.000... Equation (2-2) CA ≥ 32.6 × BR + 17.2... Equation (2-3) (Where, BR series film stiffness / softness (N.cm), AVSp series average maximum height (μm), CA series contact area ratio (%)) [Experimental Method 3] Place a 20mm × 250mm transparent conductive film test piece on a horizontal platform with the transparent conductive film facing upwards, so that the test piece protrudes 230mm from the end of the horizontal platform. Determine the stiffness-softness (BR) based on the following formula. Stiffness / softness (BR(N.cm)) = g × a × b × L 4 / (8 × δ × 10 11) (In the formula, g is 9.81 (gravitational acceleration; m / s²), a is 20 (length of the short side of the test piece; mm), b represents the specific gravity of the test piece (g / cm³), L is 230 (length of the long side of the test piece protruding from the water platform; mm), and δ represents the difference between the height of the front end of the test piece and the height of the water platform (cm)) [Experimental Method 4] On the conductive surface of the transparent conductive film, three points are determined at 1 cm intervals in the MD direction, and two points are determined symmetrically in the TD direction at 1 cm intervals from its center, for a total of five measurement points. The maximum hill height Sp based on the surface roughness is measured at each location (according to ISO 25178), and the average value is set as the average maximum hill height (AVSp) (μm). [Experimental Method 5] For the conductive surface of a transparent conductive film, the average height Rc (μm), maximum peak height Rp (μm), and average length Rsm (μm) based on line roughness are measured. In locations satisfying at least one of equations (X1) and (X2) and equation (X3), the arithmetic mean height Ra (μm) based on line roughness is measured. Furthermore, the average height Rc (μm), maximum peak height Rp (μm), average length Rsm (μm), and arithmetic mean height Ra (μm) are determined using a 3D surface shape measuring device, VertScan (manufactured by Mitsubishi System Co., Ltd., R5500H-M100 (measurement conditions: wave mode, measurement wavelength 560nm, objective lens 50x)). The determination of the maximum peak height Rp (μm), average length Rsm (μm), and arithmetic mean height Ra (μm) complies with the requirements of JIS B 0601-2001. The measurement length for the arithmetic mean height Ra (μm) is set to be between 100μm and 200μm. Rp-Rc-Ra≦0.20...Equation (X1) (Rp-Rc) / Ra≦5.0...Equation (X2) Rsm≦30... (x3) The objective lens of the aforementioned 3D surface shape measuring device, VertScan, was changed to 10x. Using the same particle resolution as the measuring device, a slice was taken in the planar direction at a height of "arithmetic mean height Ra (μm) - 15 × 10⁻³ (μm) - mean height Rc (μm)" from the average surface, and the sum of the cross-sectional areas was calculated. The following value is set as the contact area ratio (CA) (%): the sum of the cross-sectional areas divided by the area of ​​the measuring field of view multiplied by 100. [3] As in [2], the maximum value of the maximum mountain height Sp, MXSp, obtained by the aforementioned test method 4, exceeds 1.0 times and is less than 1.4 times the aforementioned average maximum mountain height AVSp, and The minimum value MNSp of the maximum mountain height Sp obtained by the aforementioned test method 4 is more than 0.6 times and less than 1.0 times the aforementioned average maximum mountain height AVSp. [4] A transparent conductive film as described in any one of [1] to [3], wherein the thickness of the aforementioned transparent conductive film is more than 10 nm and less than 100 nm. [5] A transparent conductive film as described in any one of [1] to [4], wherein the concentration of tin oxide contained in the aforementioned transparent conductive film is more than 0.5% by mass and less than 40% by mass. [6] A transparent conductive film as described in any one of [1] to [5], wherein a curable resin layer is provided between the transparent conductive film and the transparent plastic film substrate. Furthermore, a functional layer is provided on the side of the transparent plastic substrate opposite to the aforementioned transparent conductive film. [7] A transparent conductive film as described in any one of [1] to [6], wherein an easy-adhesion layer is provided on at least one side of the transparent plastic film substrate. [8] A transparent conductive film as in [7], wherein an easy-adhesion layer is disposed at at least one location between a transparent plastic film substrate and a curing resin layer, or between a transparent plastic substrate and a functional layer. [9] A transparent conductive film as described in any of [1] to [8], wherein the ON resistance specified in test method 6 is less than 10 kΩ. [Experimental Method 6] An evaluation panel was created by overlapping conductive films, with epoxy beads of 30 μm diameter, onto one side of a glass substrate. This resulted in a 20 nm thick indium-tin composite oxide conductive film (tin oxide content: 10% by mass), and a transparent conductive film. On the transparent conductive film side of this evaluation panel, a polyacetal pen with a hemispherical tip (0.8 mm radius) was used to slide the pen while applying a 2.5 N load (50,000 back-and-forth strokes, 30 mm sliding distance, 180 mm / s sliding speed). After sliding, the pen was pressed down with a 0.8 N load, and the resistance during electrical connection (ON resistance) was measured.

[10] A transparent conductive film as described in any of [1] to [9], wherein, in an adhesion test according to JIS K5600-5-6:1999, the residual area of ​​the transparent conductive film on the surface of the transparent conductive film is more than 95%. [Effects of the Invention]

[0011] According to the present invention, a transparent conductive film with excellent input strength and input stability can be provided. Furthermore, according to the present invention, in a preferred embodiment, a transparent conductive film that also possesses pen sliding durability can be provided. Simple Explanation of the Diagram

[0012] Figure 1 is a schematic side view showing an example of the transparent conductive film of the present invention. Figure 2 is a schematic side view showing another example of the transparent conductive film of the present invention. Figure 3 is a schematic side view showing yet another example of the transparent conductive film of the present invention. Figure 4 is a schematic side view showing other examples of the transparent conductive film of the present invention. Figure 5 is a conceptual diagram showing the relationship between voltage and time in a one-state sample of the present invention. Figure 6 is a schematic diagram of an apparatus for an example of the film-forming method of the present invention. Figure 7 is a schematic partial enlarged plan view for illustrating the input start load determination method of the present invention. Figure 8 is a schematic partial enlarged plan view for illustrating the pen sliding durability test method of the present invention. Figure 9 is a schematic plan view illustrating the pen sliding durability test method of the present invention. Implementation

[0013] [The form in which the invention is carried out]

[0014] 1. Transparent conductive film The transparent conductive film of the present invention is a transparent conductive film having at least one area layer of indium-tin composite oxide on a transparent plastic film substrate. By having a transparent conductive film on its surface, it can be widely used in applications utilizing its conductivity, such as as a transparent electrode for flat panel displays like liquid crystal displays and electroluminescent (EL) displays, and touch panels, and is widely used in the electrical and electronic fields. The specific layer structure of the transparent conductive film can be suitably set; for example, the structure shown in the schematic side views of Figures 1, 2, 3, and 4 can be used as examples.

[0015] The transparent conductive film in Figure 1 has a transparent conductive film 5 formed on one side of a transparent plastic film substrate 7, separated by a curable resin layer 6, and a functional layer 8 formed on the opposite side of the transparent plastic film substrate 7. By forming the curable resin layer 6 between the transparent conductive film 5 and the transparent plastic film substrate 7, monomers and oligomers can be prevented from precipitating from the transparent plastic film substrate 7 onto the transparent conductive film 5. The transparent conductive film of the present invention improves the adaptability of input strength and input stability by controlling the input start-up load and voltage drop time (described later), and further improves the adaptability of input strength and input stability by preventing the precipitation of oligomers. Furthermore, by using the curable resin layer 6 and the functional layer 8 to prevent the precipitation of monomers and oligomers, the transparency and visibility of the transparent conductive film can be further improved. Additionally, by having the curable resin layer 6 and / or the functional layer 8, the stiffness and flexibility of the transparent conductive film (described later) can be adjusted. Also, depending on the rigidity of the transparent plastic film substrate, the curable resin layer 6 and / or the functional layer 8 may not be necessary.

[0016] In one embodiment, the transparent conductive film of the present invention is formed by depositing an easy-bond layer on at least one side of a transparent plastic film substrate. For example, as shown in FIG. 2, the curable resin layer 6 and the transparent plastic film substrate 7 are bonded together with an easy-bond layer 9. Alternatively, as shown in FIG. 3, the functional layer 8 and the transparent plastic film substrate 7 are bonded together with an easy-bond layer 9. Also, as shown in FIG. 4, the curable resin layer 6 and the functional layer 8 are respectively bonded to the transparent plastic film substrate 7 with easy-bond layers 9. The presence of the easy-bond layer 9 more effectively prevents the curable resin layer 6 and / or the functional layer 8 from peeling off from the transparent plastic film substrate 7 due to external forces.

[0017] The transparent conductive film of the present invention is characterized (characteristic 1) in that the input start load determined by test method 1 is greater than 15g and less than 25g. By making the input start load less than a predetermined value, input comfort can be improved.

[0018] [Experimental Method 1] An indium-tin composite oxide conductive film (tin oxide content: 10% by mass) with a thickness of 20 nm is formed on one side of a glass substrate. On the surface of this film, epoxy resin dot-shaped interstices (60 μm x 60 μm x 5 μm) are formed into a square grid with a spacing of 4 mm to serve as a panel. On the conductive film side of this panel, an adhesive rectangular frame with a thickness of 105 μm and an inner circumference of 190 mm x 135 mm is sandwiched between them. Meanwhile, a transparent conductive film is superimposed with the conductive films facing each other to create an evaluation panel. From the transparent conductive film side of this evaluation panel, a polyacetal pen with a hemispherical tip of 0.8 mm radius is continuously pressed at the center of the 4-dot grid of the dot-shaped interstices. The pressure at which the resistance value begins to stabilize is set as the input start load. Here, "stable resistance value" means, for example, a state where the resistance value varies within ±5% of the average value.

[0019] Furthermore, the aforementioned transparent conductive film is characterized (characteristic 2) by having a voltage drop time of 0.00 ms to 0.40 ms as determined by test method 2. By keeping the voltage drop time within a predetermined range, the electrically stable contact time can be extended. By keeping the input start load within a predetermined range, error input prevention can be improved. Furthermore, by keeping the voltage drop time within a predetermined range, input stability, such as stroke stability and rapid writing speed, can be improved. While the rationale for achieving this input stability effect should not be interpreted as being limited to a specific theory, it is believed that the extended electrically stable contact time further reduces electrically unstable contact states. As a result, the input instability time is shortened; for example, during continuous text recording, text blurring can be prevented, and text blurring during rapid writing can be reduced. Furthermore, for example, it can solve the problem of text becoming blurry and not being displayed on a touch panel when writing on it. Therefore, it is possible to clearly draw the desired text, pictures, etc., on a resistive film touch panel. For example, it can also express the downward strokes of characters as if they were written with a brush. A transparent conductive film with features 1 (input start load) and feature 2 (voltage drop time) is extremely useful in applications such as resistive film touch panels.

[0020] The voltage drop time is preferably below 0.39 milliseconds, more preferably below 0.35 milliseconds, and even more preferably below 0.30 milliseconds, and the shorter the better. Furthermore, the voltage drop time can be above 0.01 milliseconds, for example, above 0.02 milliseconds. That is, the voltage drop time is preferably 0.01~0.39 milliseconds, more preferably 0.01~0.35 milliseconds, and even more preferably 0.02~0.30 milliseconds.

[0021] [Experimental Method 2] The aforementioned evaluation panel was connected to a constant voltage power supply of 6V. Using a pen with a hemispherical tip and a radius of 0.8mm, applied a 50gf load and pressed the center of the four-point grid of the dotted spacer at intervals of 5 times per second from the transparent conductive film side. The time from when the pen begins to leave the transparent conductive film and the voltage decreases from 6V to when the voltage reaches 5V was measured was defined as the voltage loss time. For example, Figure 5 is a conceptual diagram showing the relationship between voltage and time in one state of the present invention, with the horizontal axis 13 representing the time axis, the vertical axis 14 representing the voltage, and the voltage loss time 15 being measured.

[0022] The aforementioned transparent conductive film preferably has an ON resistance of 10kΩ or less as specified in Test Method 6 (Characteristic 3). The lower the ON resistance, the better the pen's sliding durability. The ON resistance is preferably 8kΩ or less, more preferably 5kΩ or less, even more preferably 3kΩ or less, and particularly preferably 1.0kΩ or less. Furthermore, the ON resistance can, for example, be 0.1kΩ or more, 2kΩ or more, or 4kΩ or more. That is, the ON resistance is preferably 0.1~10kΩ, more preferably 0.1~8kΩ, even more preferably 0.1~5kΩ, even more preferably 0.1~3kΩ, and particularly preferably 0.1~1kΩ. Additionally, it can be 2~10kΩ, 2~8kΩ, 2~5kΩ, 2~3kΩ, 4~10kΩ, 4~8kΩ, or 4~5kΩ. [Experimental Method 6] An evaluation panel was created by overlapping conductive films, with epoxy beads of 30 μm diameter, onto one side of a glass substrate. This resulted in a 20 nm thick indium-tin composite oxide conductive film (tin oxide content: 10% by mass), and a transparent conductive film. On the transparent conductive film side of this evaluation panel, a polyacetal pen with a hemispherical tip (0.8 mm radius) was used to slide the pen while applying a 2.5 N load (50,000 back-and-forth strokes, 30 mm sliding distance, 180 mm / s sliding speed). After sliding, the pen was pressed down with a 0.8 N load, and the resistance during electrical connection (ON resistance) was measured.

[0023] The aforementioned transparent conductive film preferably has a film stiffness (BR) of 0.38 N·cm or more and 0.90 N·cm or less, as determined by test method 3. By setting the film stiffness (BR) to a predetermined value or higher, the input initial load can be set to a predetermined value or higher. Furthermore, by setting the film stiffness (BR) to a value lower than a predetermined value, the ON resistance can be set to a value lower than a predetermined value. Also, reducing the film stiffness (BR) is useful in reducing the input initial load. The film stiffness (BR) is more preferably 0.42 N·cm or more, and even more preferably 0.46 N·cm or more. Furthermore, it is more preferably 0.80 N·cm or less, even more preferably 0.70 N·cm or less, and particularly preferably 0.60 N·cm or less. That is, the stiffness-to-softness (BR) of the thin film is preferably 0.42~0.80 N·cm, even more preferably 0.42~0.70 N·cm, and particularly preferably 0.46~0.60 N·cm.

[0024] [Experimental Method 3] Place a 20mm × 250mm transparent conductive film test piece on a horizontal platform with the transparent conductive film facing upwards, so that the test piece protrudes 230mm from the end of the platform. Determine the stiffness-softness (BR) based on the following formula. Note that the stiffness-softness value will change when the transparent conductive film is facing downwards. Stiffness / softness (BR(N.cm)) = g × a × b × L 4 / (8 × δ × 10 11) (In the formula, g is 9.81 (gravitational acceleration; m / s²), a is 20 (length of the short side of the test piece; mm), b represents the specific gravity of the test piece (g / cm³), L is 230 (length of the long side of the test piece protruding from the water platform; mm), and δ represents the difference between the height of the front end of the test piece and the height of the water platform (cm))

[0025] Preferably, the average (AVSp) of the maximum peak height Sp of the conductive surface obtained by test method 4 satisfies the following formula (2-1). The input initial load is governed by two parameters: film stiffness (BR) and average maximum peak height (AVSp). By making the average maximum peak height (AVSp) above or above the predetermined value obtained by film stiffness (BR), the input initial load can be made below or above the predetermined value. Furthermore, by making the average maximum peak height (AVSp) below the predetermined value, the input initial load can be made above or above the predetermined value, and there is also a possibility of adjusting the voltage drop time within a better range. 4.7×BR-3.6≦AVSp<4.7×BR-1.8...Equation (2-1) (Where, BR series film stiffness / softness (N.cm), AVSp series average maximum peak height (μm)) [Experimental Method 4] On the conductive surface of the transparent conductive film, three points are determined at 1 cm intervals in the MD direction, and two points are determined symmetrically in the TD direction at 1 cm intervals from its center, for a total of five measurement points. The maximum hill height Sp based on the surface roughness is measured at each location (according to ISO 25178), and the average value is set as the average maximum hill height (AVSp) (μm).

[0026] The inequality relationship on the left side of equation (2-1) is preferably 4.7×BR-3.5≦AVSp, and even more preferably 4.7×BR-3.4≦AVSp. The inequality relationship on the right side of equation (2-1) is preferably AVSp<4.7×BR-1.9, and even more preferably AVSp<4.7×BR-2.0. That is, it is more preferably 4.7×BR-3.5≦AVSp<4.7×BR-1.9, and even more preferably 4.7×BR-3.4≦AVSp<4.7×BR-2.0.

[0027] The aforementioned transparent conductive film preferably has an average maximum height (AVSp) that satisfies the following formula (2-2). If the average maximum height (AVSp) is above a predetermined value, the transparent conductive film can be rolled into a roll without any hindrance. The average maximum height (AVSp) is more preferably 0.010 (μm) or more, and even more preferably 0.020 (μm) or more. Furthermore, by making the average maximum height (AVSp) below a predetermined value, accidental electrical contact can be more effectively prevented. 0.005≦AVSp≦12.000... Equation (2-2) (In the formula, the average maximum mountain height of the AVSp system is (μm)) That is, AVSp is preferably 0.010~12.000μm, and even more preferably 0.020~12.000μm.

[0028] The aforementioned transparent conductive film preferably has a contact area ratio (CA) obtained by test method 5 that satisfies the following equation (2-3). By making the contact area ratio (CA) above a predetermined value, the voltage drop time can be made below a predetermined value. The reason is that the larger the contact area ratio (CA), the higher the stability of the electrical contact between the conductive layers. Therefore, time can be gained before the contact area becomes unstable when the pen, finger, etc. leave the transparent conductive film of the resistive film touch panel. In addition, the contact area ratio (CA) is increased with the increase of stiffness (BR) in equation (2-3) because the larger the stiffness (BR), the faster the pen, finger, etc. leave the transparent conductive film of the resistive film touch panel. Therefore, a transparent conductive film with a large contact area ratio (CA) must be used. CA ≥ 32.6 × BR + 17.2... Equation (2-3) (Where, BR series film stiffness / softness (N.cm), CA series contact area ratio (%))

[0029] [Experimental Method 5] For the conductive surface of a transparent conductive film, the average height Rc (μm), maximum peak height Rp (μm), and average length Rsm (μm) based on line roughness are measured. In locations satisfying at least one of equations (X1) and (X2) and equation (X3), the arithmetic mean height Ra (μm) based on line roughness is measured. Furthermore, the average height Rc (μm), maximum peak height Rp (μm), average length Rsm (μm), and arithmetic mean height Ra (μm) are determined using a 3D surface shape measuring device, VertScan (manufactured by Mitsubishi System Co., Ltd., R5500H-M100 (measurement conditions: wave mode, measurement wavelength 560nm, objective lens 50x)). The determination of the maximum peak height Rp (μm), average length Rsm (μm), and arithmetic mean height Ra (μm) complies with the requirements of JIS B 0601-2001. The measurement length for the arithmetic mean height Ra (μm) is set to be between 100μm and 200μm. Rp-Rc-Ra≦0.20...Equation (X1) (Rp-Rc) / Ra≦5.0...Equation (X2) Rsm≦30... (x3) The objective lens of the aforementioned 3D surface shape measuring device, VertScan, was changed to 10x. Using the same particle resolution as the measuring device, a section was cut in the plane at a height of "arithmetic mean height Ra (μm) - 15 × 10⁻³ (μm) - mean height Rc (μm)" from the average surface (the average line is 3D transformed). The sum of the cross-sectional areas was calculated. The following value is set as the contact area ratio (CA) (%): the sum of the cross-sectional areas divided by the area of ​​the measuring field of view multiplied by 100.

[0030] In the aforementioned test method 5, the "arithmetic mean height Ra (μm) - 15 × 10⁻³ (μm)" is considered for the following reasons: Most of the transparent conductive film in contact with the transparent conductive glass consists of protrusions at the average height of the transparent conductive film. Since it is difficult to accurately calculate the contact area with these protrusions at this average height, the cross-sectional area of ​​the transparent conductive film's transparent conductive film side at a height slightly smaller than the aforementioned average protrusion height (= a height 15 × 10⁻³ (μm) lower than the average height of the transparent conductive film) is used as a substitute indicator (this height is based on the average height Rc (μm) descending from the average surface). Here, if the arithmetic mean roughness Ra of JIS B 0601-2001 is used as the average protrusion height of the transparent conductive film, the arithmetic mean roughness Ra becomes larger than the actual average protrusion height of the transparent conductive film due to the influence of a small number but very high coarse protrusions located on the transparent conductive film side of the transparent conductive film, which is therefore undesirable. Therefore, in order to eliminate the influence of coarse protrusions, the arithmetic mean roughness Ra (μm) is measured in places that satisfy at least one of equations (X1) and (X2) and equation (X3).

[0031] The relationship between CA and BR shown in equation (2-3) is preferably CA≧32.6×BR+17.5, and even more preferably CA≧32.6×BR+18.0.

[0032] The maximum value MXSp of the aforementioned transparent conductive film, determined by the aforementioned test method 4, is preferably more than 1.0 times and less than 1.4 times the aforementioned average maximum height AVSp (more preferably more than 1.0 times and less than 1.40 times). By making the maximum value MXSp below a predetermined value, the in-plane distribution of the high protrusions of the transparent conductive film becomes uniform, allowing for touch panel input operations with the same input load in any location, which is preferable. More preferably, it is less than 1.3 times. Even more preferably, it is less than 1.2 times.

[0033] The minimum value MnSp of the maximum peak height Sp obtained by the aforementioned test method 4 is preferably 0.6 times to 1.0 times (more preferably 0.60 times to 1.0 times) of the aforementioned average maximum peak height AVSp. By making the minimum value MNSp a predetermined value or higher, the in-plane distribution of the high protrusions of the transparent conductive film becomes uniform, and the touch panel can be input with the same input load in any location, which is preferable. More preferably, it is 0.7 times or higher, and even more preferably, it is 0.8 times or higher. Furthermore, by ensuring that both the maximum value MXSp and the minimum value MNSp are within a predetermined range, the variation in the input starting load can be made less than ±5% of the average value. This also prevents variations in the input starting load among work-in-process.

[0034] The total light transmittance of the aforementioned transparent conductive film is, for example, 70% or more and 95% or less, preferably 80% or more and 95% or less, and even more preferably 85% or more and 90% or less.

[0035] 2. Transparent conductive film The transparent conductive film contains indium-tin composite oxide. The concentration of tin oxide in the transparent conductive film is preferably 0.5% by mass or more and 40% by mass or less. If it contains 0.5% by mass or more of tin oxide, the surface resistivity of the transparent conductive film reaches a practical level, which is preferable. Furthermore, by making the tin oxide concentration 40% by mass or less, the tin oxide concentration in the transparent conductive film can be made close to the tin oxide concentration in the transparent conductive glass substrate for touch panels. The closer the tin oxide concentrations of the transparent conductive film and the transparent conductive film of the glass substrate are, the easier it is for the two transparent conductive films to make electrical contact, further improving the input strength and input stability. The tin oxide concentration of the transparent conductive film is more preferably 25% by mass or less, even more preferably 20% by mass or less, particularly preferably 18% by mass or less, more preferably 1% by mass or more, and even more preferably 2% by mass or more. That is, the tin oxide concentration is more preferably 1 to 25% by mass, even more preferably 1 to 20% by mass, and particularly preferably 2 to 18% by mass.

[0036] Furthermore, generally speaking, the tin oxide concentration in the transparent conductive glass substrate used for touch panels is 10% by mass. The difference between the tin oxide concentration of the transparent conductive film and the tin oxide concentration of the glass substrate is, for example, 30% by mass or less, preferably 20% by mass or less, and more preferably 10% by mass or less.

[0037] The crystallinity of the transparent conductive film can be any value between 0% and 100%, preferably between 10% and 100%, and even more preferably between 50% and 100%. The higher the crystallinity, the better the pen's glide properties.

[0038] The surface resistivity of the transparent conductive film is, for example, above 50Ω / □ and below 900Ω / □, preferably above 50Ω / □ and below 700Ω / □, and even more preferably above 70Ω / □ and below 500Ω / □.

[0039] The thickness of the transparent conductive film is preferably 10 nm to 100 nm. If the thickness of the transparent conductive film is 10 nm or more, the entire transparent conductive film adheres to the transparent plastic film substrate or the curable resin layer described later, resulting in stable film quality and easily stable surface resistivity within a preferred range. Furthermore, it is also effective in reducing the ON resistance specified by Test Method 6. More preferably, the thickness of the transparent conductive film is 13 nm or more, and even more preferably 16 nm or more. Furthermore, if the thickness of the transparent conductive film is 100 nm or less, the crystal grain size and crystallinity of the transparent conductive film become appropriate, and the total light transmittance reaches a practical level, which is therefore preferable. More preferably, it is 50 nm or less, even more preferably 30 nm or less, and particularly preferably 25 nm or less. That is, the thickness of the transparent conductive film is preferably 13 to 50 nm, even more preferably 16 to 30 nm, and particularly preferably 16 to 25 nm.

[0040] In the adhesion test according to JIS K5600-5-6:1999 on the surface of the transparent conductive film, the residual area ratio of the transparent conductive film is preferably 95% or more, more preferably 99% or more, and especially preferably 99.5% or more. Because the residual area ratio of the transparent conductive film is within the above range in the adhesion test, the transparent conductive film, which is a transparent plastic film substrate, a curable resin layer (described later), and the transparent conductive film are in close contact. Even with continuous input to the touch panel using a pen, cracking, peeling, and abrasion of the transparent conductive film can be suppressed. Furthermore, even when a force greater than that assumed for normal use is applied, cracking and peeling of the transparent conductive film can still be suppressed, which is therefore preferable.

[0041] The aforementioned method for forming the transparent conductive film is not particularly limited. For example, it is preferred to form a transparent conductive film of indium-tin composite oxide on at least one side of a transparent plastic film substrate 7 (hereinafter referred to as the film to be treated), on which a curable resin layer 6 can be formed, by sputtering. In order to manufacture transparent conductive films with high productivity, it is preferred to use a so-called roller sputtering apparatus in which the film to be treated is supplied from a film roll, and after film formation, it is rolled into a film roll shape.

[0042] Figure 6 is a schematic diagram of an example of the film-forming section in a roller sputtering apparatus. In this example, the film to be processed 1, fed from a film roll (not shown), travels while partially contacting the surface of a central roller 2. An indium-tin sputtering target 4 is placed inside a chimney 3 with an opening facing the contact portion between the film to be processed 1 and the central roller 2, and a thin film of indium-tin composite oxide is deposited on the surface of the film to be processed 1 traveling on the central roller 2. Furthermore, the temperature of the central roller 2 can be controlled using a temperature controller (not shown).

[0043] As a target, a sintering target using indium-tin composite oxide is preferred. To improve production efficiency, multiple sintering targets of indium-tin composite oxide can be set in the flow direction of the thin film.

[0044] Regarding the formation of the film-forming gas environment, it is preferable to allow oxygen and inert gases (such as argon) to flow in simultaneously using a mass flow controller as needed. By adding oxygen, the surface resistance and total light transmittance of the transparent conductive film can be adjusted more appropriately. The flow rate ratio (volume ratio) of oxygen and inert gases (oxygen / inert gas) is, for example, 0.005 or more, preferably 0.010 or more, more preferably 0.020 or more, 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. That is, the flow rate ratio (volume ratio) of oxygen and inert gases (oxygen / inert gas) is, for example, 0.005 to 0.15, preferably 0.010 to 0.1, more preferably 0.020 to 0.07, and even more preferably 0.020 to 0.05. Furthermore, in a film-forming gas environment, a gas containing hydrogen atoms can be introduced while using a mass flow controller (there are no particular limitations for gases containing hydrogen atoms, such as hydrogen, ammonia, or a hydrogen + argon mixture. However, water is an exception).

[0045] The median value (the midpoint between the maximum and minimum values) of the partial pressure ratio of water to inactive gas in the film-forming gas environment (water pressure / inactive gas partial pressure) is preferably 7.00 × 10⁻³ or less, more preferably 5.00 × 10⁻³ or less, and even more preferably 3.00 × 10⁻³ or less. The less water in the film-forming gas environment, the more suitable the quality of the transparent conductive film, the easier it is to achieve an optimal surface resistivity value, and the higher the certainty of crystallization. However, although it is possible to control the water content with achieving a vacuum level as a target, it is better to measure the water content (water pressure) during film formation for the following two reasons: First, if film formation is performed on a plastic film by sputtering, the film is heated, releasing water from the film. The vacuum level does not reflect the effect of this released water content. Second, the effect of water at the center of the roller when forming film from a rolled-up film is not reflected in the vacuum level. If the film roll is held in a vacuum chamber, water in the outer layer of the roll is easily removed, but water in the inner layer of the roll is difficult to remove. When the vacuum level is reached, the film roll stops moving, while the film is moving during film formation. The inner layer of the film roll, which contains a lot of water, is rolled out one after another. Therefore, the water content in the film-forming gas environment increases, and the increase is even greater than the water content when the vacuum level is reached.

[0046] For the thin film roll used to form a transparent conductive film, the height difference between the most convex and the most concave part at the end face of the roll is preferably less than 10 mm, more preferably less than 8 mm, and even more preferably less than 4 mm. If it is less than 10 mm, when the thin film roll is put into the sputtering apparatus, water and organic components from the end face of the film become difficult to release, thus improving the quality of the transparent conductive film.

[0047] Ideally, the thin film to be treated should undergo a bombardment step before the formation of the transparent conductive film. The bombardment step refers to applying a voltage to generate plasma by discharging under conditions where only inert gases such as argon flow in, or a mixture of reactive gases such as oxygen and inert gases flow in. Specifically, ideally, the thin film is bombarded using an SUS target or similar method via RF sputtering. By exposing the thin film to the plasma through the bombardment step, water and organic components are released from the film. This reduces the amount of water and organic components released during the formation of the transparent conductive film, resulting in a better film quality. Furthermore, the bombardment step activates the layers in contact with the transparent conductive film, thus improving the adhesion of the transparent conductive film and further enhancing pen sliding durability.

[0048] Ideally, a protective film with low water absorption is attached to the opposite side of the surface on which the transparent conductive film is formed, in the case of the aforementioned treated film 1. By attaching the protective film, it becomes difficult for gases such as water to be released from the treated film 1, thus improving the quality of the transparent conductive film. Examples of substrates for the aforementioned protective film include, for example, olefins such as polyethylene, polypropylene, and cycloolefins.

[0049] During film formation, the film to be treated 1 is cooled to, for example, below 0°C, preferably below -5°C. By cooling the film to be treated 1, the release of impurities such as water and organic gases from the film can be suppressed, and the film quality of the transparent conductive film can be appropriately adjusted. The film temperature during film formation can be replaced by the set temperature of a temperature control machine that adjusts the temperature of the center roller that contacts the traveling film.

[0050] The sputtering apparatus preferably has an exhaust device such as a rotary pump, a turbomolecular pump, or a cryopump. The exhaust device allows for control of the moisture content in the film-forming gas environment.

[0051] Ideally, after the transparent conductive film of indium-tin composite oxide is deposited on the thin film, a heat treatment is applied in an oxygen-containing gas environment at a temperature of 80°C to 200°C for 0.1 to 12 hours. Setting the temperature above 80°C improves the crystallinity of the transparent conductive film, further enhancing pen sliding durability. Setting the temperature below 200°C ensures the planarity of the transparent plastic film.

[0052] 3. Transparent plastic film substrate The transparent plastic film substrate used in this invention refers to a film formed by melt extrusion or solution extrusion of organic polymers, which is then stretched, cooled, and heat-fixed in the length and / or width directions as needed. Examples of the aforementioned organic polymers include: polyolefins such as polyethylene and polypropylene; polyesters such as polyethylene terephthalate, polyethylene 2,6-naphthalenedicarboxylate, polypropylene terephthalate, and polybutylene terephthalate; polyamides such as nylon 6, nylon 4, nylon 66, and nylon 12; polyimides, polyamide-imides, polyethersulfone, polyetheretherketone, polycarbonate, polyaromatic esters, cellulose propionate, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyetherimide, polyphenylene sulfide, polyphenylene ether, polystyrene, para-polystyrene, and norbornene polymers.

[0053] Among these organic polymers, suitable options include polyethylene terephthalate (PET), polyethylene terephthalate (PTA), polyethylene terephthalate (PET), polyethylene 2,6-p-naphthalenedicarboxylate (PET), para-polystyrene, norcamphene polymers, polycarbonate, and polyaromatic esters. Furthermore, these organic polymers can also be copolymerized with small amounts of monomers from other organic polymers or blended with other organic polymers.

[0054] Within the scope of the present invention, surface activation treatments such as corona discharge treatment, glow discharge treatment, flame treatment, ultraviolet irradiation treatment, electron beam irradiation treatment, and ozone treatment can be applied to transparent plastic film substrates.

[0055] The thickness of the transparent plastic film substrate is preferably in the range of 125 μm to 280 μm, and more preferably 150 μm to 250 μm. The thicker the transparent plastic film substrate, the easier it is for the film's stiffness-flexibility (BR) to increase, and the easier it is for the average maximum peak height (AVSp) to satisfy the right side of equation (2-1). Furthermore, if the thickness of the transparent plastic film substrate is 125 μm or more, mechanical strength can be maintained, thus improving the prevention of erroneous input, especially when used in touch panels. In addition, when used in touch panels, the deformation of the pen input is small, and the pen sliding durability is excellent, which is also preferable. On the other hand, if the thickness is 280 μm or less, it can maintain suitable input strength and excellent input stability when used in touch panels, which is also preferable.

[0056] 4. Curing resin layer For example, a curable resin layer is formed between the transparent plastic film substrate and the transparent conductive film, becoming the base layer of the transparent conductive film. Furthermore, it can prevent monomers and oligomers generated from the transparent plastic film substrate from precipitating onto the transparent conductive film, thus not hindering the comfortable input of the touch panel, which is preferable. Additionally, through the use of an easy-adhesion layer, the transparent conductive film can adhere strongly and firmly to the curable resin layer, and the force applied to the transparent conductive film can be dispersed, thus suppressing cracking, peeling, and wear of the transparent conductive film under pen sliding durability tests, which is also preferable.

[0057] The resin used in the curing resin layer is not particularly limited if it is a resin that is cured by applying energy such as heat, ultraviolet radiation, or electron beam irradiation, and a curing agent. Examples include silicone resins, acrylic resins, methacrylic resins, epoxy resins, melamine resins, polyester resins, and urethane resins. These can be one type or a combination of two or more. From a production point of view, it is preferable to use an ultraviolet-curing resin as the main component.

[0058] Examples of UV-curable resins include, for instance, multifunctional acrylate resins made from polyols such as acrylic or methacrylates; and multifunctional urethane acrylate resins synthesized from diisocyanates, polyols, and hydroxyalkyl esters of acrylic or methacrylates. Depending on the requirements, monofunctional monomers, such as vinylpyrrolidone, methyl methacrylate, and styrene, can be added to these multifunctional resins to copolymerize them.

[0059] The curable resin layer preferably contains a curing reaction initiator at least before curing. The curing reaction initiator can be selected depending on the type of curing of the curable resin, and examples include: free radical polymerization initiators such as thermal polymerization initiators and photopolymerization initiators, and curing agents, with photopolymerization initiators being preferred. The amount of the curing reaction initiator is approximately 1 to 5 parts by mass relative to 100 parts by mass of the curable resin.

[0060] As photopolymerization initiators, known compounds that absorb ultraviolet light to generate free radicals can be used without particular restriction; examples include various benzoin derivatives, phenyl ketone derivatives, benzophenone derivatives, etc.

[0061] The curing resin layer preferably contains particles. These particles can create unevenness on the surface of the curing resin layer. Therefore, with the inclusion of particles, the contact area ratio (CA) essentially decreases from 100%, and on the other hand, the control of the average maximum peak height (AVSp) becomes easier. Furthermore, in cases where the stiffness (BR) decreases with increasing particle quantity, the stiffness (BR) can also be adjusted by controlling the particle quantity. Additionally, particles can more effectively exhibit various properties such as pen slip resistance, Newton's ring resistance, and film roll-up properties. Moreover, when the amount of relatively large particles (e.g., particle A described later) added is small, and the amount of relatively small particles (e.g., particle B used in conjunction with particle A described later) is large, compared to adding particles of the same particle size, there is a tendency for the contact area ratio (CA) to increase and the average maximum peak height (AVSp) to increase.

[0062] Examples of the aforementioned particles include inorganic particles and organic particles, with inorganic particles being preferred. Examples of inorganic particles include silicon oxide particles. Examples of organic particles include particles containing polyester resin, polyolefin resin, polystyrene resin, polyamide resin, etc. The particles can be one type or two or more types.

[0063] The average particle size of the aforementioned particles is, for example, 0.01 μm to 10 μm, preferably 0.03 μm to 5 μm, more preferably 0.05 μm to 3 μm, and most preferably 0.05 μm to 1.8 μm. A larger average particle size allows for a larger average maximum height (AVSp) of the transparent conductive layer. Furthermore, the average maximum height can be increased not only by increasing the average particle size, but also by increasing the resin concentration (solid component concentration) in the coating solution of the curing resin (described later) and by thinning the thickness of the curing resin layer.

[0064] Furthermore, the aforementioned standard deviation of particle size is, for example, less than 20% of the average particle size, preferably less than 10% of the average particle size, and more preferably less than 5% of the average particle size. The smaller the standard deviation of particle size, the greater the contact area ratio (CA) of the transparent conductive film.

[0065] In one sample, it is preferable to use particle B with a number average particle size of 0.01 μm or more and less than 1.0 μm. In another sample, it is preferable to use particle A with a number average particle size of 0.4 μm or more and less than 1.8 μm, which is larger than particle B, and particle B with a number average particle size of 0.01 μm or more and less than 1.0 μm. The average particle size of particle B is preferably 0.05 μm or more. If the average maximum height AVSp increases (for example, becomes 0.6 μm or more), the contact area ratio CA may become too small. However, if both particle A and particle B are used, the contact area ratio can be appropriately adjusted. Furthermore, if the average maximum height AVSp becomes greater than the right side of equation (2-1) (4.7 × BR - 1.8), the contact area ratio CA will become too small even if both particle A and particle B are used. Therefore, the average maximum height AVSp must be less than the right side of equation (2-1).

[0066] When a particle B is included, the amount of particle B in the curing resin layer is, for example, 0.1% to 25% by mass, and preferably 0.5% to 18% by mass, relative to 100% by mass of the solid content of the curing resin layer. Furthermore, when the resin layer contains two types of particles, A and B, the amount of particle A in the cured resin layer is, for example, 0.1% to 5% by mass relative to 100% of the solid content of the cured resin layer. The amount of particle B in the cured resin layer is preferably more than the amount of particle A relative to 100% of the solid content of the cured resin layer, for example, more than 5% by mass and less than 30% by mass, preferably more than 6% to 15% by mass.

[0067] By adjusting the size and quantity of particles as described above, the average maximum height AVSp of the transparent conductive layer can be made to satisfy equation (2-1), while the contact area ratio CV will not become too small. Furthermore, the stiffness BR of the thin film can also be adjusted. Therefore, the input start-up load can be controlled within an appropriate range, the voltage drop time can be shortened, and suitable input strength and input stability can be achieved.

[0068] The thickness of the curable resin layer is preferably in the range of 0.1 μm to 15 μm. More preferably, it is in the range of 0.5 μm to 10 μm, and even more preferably, it is in the range of 1 μm to 8 μm. A thickness of 0.1 μm or more in the curable resin layer allows for the formation of sufficient protrusions, which is preferable. On the other hand, a thickness of 15 μm or less results in better manufacturability. Furthermore, a thicker curable resin layer tends to increase the rigidity (BR) of the transparent conductive film.

[0069] The curing resin layer may contain a resin that is immiscible with the curing resin (hereinafter referred to simply as immiscible resin). By dispersing the immiscible resin in the curing resin layer, unevenness can be formed on the surface of the curing resin layer, thereby increasing the surface roughness over a large area. Examples of immiscible resins include: polyester resin, polyolefin resin, polystyrene resin, polyamide resin, etc.

[0070] The curing resin layer is formed by liquidening the curing resin before curing, applying it to the laminated object (transparent plastic film substrate, easy-adhesive layer, etc.), and then curing it. In addition to the aforementioned curing resin, the coating may also contain curing reaction initiators (free radical polymerization initiators such as thermal polymerization initiators and photopolymerization initiators, curing agents, etc., preferably photopolymerization initiators), particles, resins immiscible with the curing resin, solvents, etc. Furthermore, other known additives, such as silicone-based leveling agents, may be added to this coating liquid as needed. There are no particular limitations on the solvents used; for example, alcohol solvents such as ethanol and isopropanol; ester solvents such as ethyl acetate and butyl acetate; ether solvents such as dibutyl ether and ethylene glycol monoethyl ether; ketone solvents such as methyl isobutyl ketone and cyclohexanone; and aromatic hydrocarbon solvents such as toluene, xylene, and naphthol can be used alone or in combination.

[0071] The concentration of the curing resin in the coating solution (referred to as the solids concentration) can be appropriately selected considering factors such as viscosity corresponding to the coating method. The solids concentration is, for example, 35% by mass or more and 58% by mass or less, preferably 42% by mass or more and 55% by mass or less. If the solids concentration is high and the thickness of the curing resin layer is thin (e.g., 4.0 μm or less), the average maximum height of the curing resin layer tends to increase under the relationship of Equation (2-1), while the contact area ratio CA tends to decrease. Furthermore, if the solids concentration exceeds 58% by mass (e.g., around 58% by mass or 65% by mass), the thickness of the curing resin layer is 4.0 μm or less, and when using both particles A and B, the particle size of particle A is set to 0.80 μm or less, and the amount of particle A is 4% by mass or less relative to 100% by mass of the solids in the curing resin layer, it is easy to achieve an average maximum height and contact area ratio CA within an appropriate range according to the viewpoint of Equation (2-1).

[0072] There are no particular limitations on the method of applying the aforementioned coating solution to the laminated object; for example, known methods such as rod coating, gravure coating, and reverse coating can be used. The solvent in the coating solution is evaporated and removed in a subsequent drying step. If an immiscible resin (such as polyester resin) is dissolved in the coating solution, in this drying step, the immiscible resin becomes particles and precipitates into the UV-curable resin. After drying the coating film, a cured resin layer can be formed by performing appropriate treatments (e.g., UV irradiation) corresponding to the type of curing.

[0073] For the coated surface of the laminated object, an adhesion-enhancing treatment can be performed as needed before applying the coating liquid to improve the adhesion of the hardened resin layer. Examples of adhesion-enhancing treatments include: discharge treatment methods such as glow discharge or corona discharge to increase carbonyl, carboxyl, and hydroxyl groups; and chemical treatment methods using acids or alkalis to increase polar groups such as amine, hydroxyl, and carbonyl groups.

[0074] As mentioned above, to keep the average maximum peak height AVSp and the contact area ratio CA within a given range, various factors must be adjusted. The details are as described above, but to simplify, these factors can be adjusted using the following relationships: Generally, the absolute value of the average maximum peak height AVSp tends to increase if the particle size is large, the solid content is high, or the resin layer is thin. The average maximum peak height AVSp satisfying equation (2-1) varies with the stiffness BP; the smaller the stiffness BP, the smaller the average maximum peak height AVSp. Furthermore, generally, if the average maximum peak height AVSp increases, the contact area ratio CA decreases. However, if two particle sizes are used as the average particle size added to the resin layer, and the amount of large particles added is reduced, the average maximum peak height AVSp increases, and the contact area ratio CV increases. When using two particle sizes, the less large particles are added, the greater the influence of the average particle size of the small particles on the contact area ratio CA.

[0075] 5. Functional layer In addition to being formed on the opposite side of the transparent plastic film substrate, the functional layer is preferably the same as the aforementioned curable resin layer. The description of the aforementioned curable resin layer applies to the functional layer in all aspects except for particle size and quantity. By depositing a functional layer on the transparent plastic film substrate, it is possible to prevent monomers and oligomers from precipitating from the transparent plastic film substrate, thus suppressing the reduction in the visibility of the transparent conductive film. Furthermore, the stiffness / softness (BR) of the transparent conductive film can be adjusted. Moreover, by having a functional layer on the transparent plastic film substrate, scratches caused by input with a pen or other means become less likely, which is preferable.

[0076] When particles (particle C) are incorporated into the functional layer, the average particle size of particle C is, for example, 0.01 μm or more and 10 μm or less, preferably 0.1 μm or more and 7 μm or less, and more preferably 1 μm or more and 5 μm or less. The amount of particle C in the functional layer is preferably 0.1 parts by mass to 60 parts by mass, more preferably 0.3 parts by mass to 40 parts by mass, and even more preferably 0.5 parts by mass to 30 parts by mass. The stiffness / softness (BR) of the transparent conductive film can be adjusted by the amount of particle C. Furthermore, particle C can be used to form surface protrusions in the functional layer, while maintaining the film's rollability.

[0077] In the adhesion test according to JIS K5600-5-6:1999 on the surface of the functional layer, the residual area ratio of the functional layer is preferably 95% or more, more preferably 99% or more, and particularly preferably 99.5% or more. With the residual area ratio of the functional layer within the above range under the adhesion test, the transparent conductive film (transparent plastic film substrate) and the functional layer adhere tightly. Even with continuous input to the touch panel using a pen, appearance defects such as cracking, peeling, and abrasion of the functional layer can be suppressed. Furthermore, even when a force greater than that assumed for normal use is applied, cracking and peeling of the functional layer can still be suppressed, which is therefore superior.

[0078] When a transparent conductive film has a functional layer and a cured resin layer, the thicknesses of the functional layer and the cured resin layer are preferably the same. Furthermore, the absolute values ​​of the thickness difference between the functional layer and the cured resin layer preferably have the following relationship. 0.1μm ≤ |thickness of the cured resin layer - thickness of the functional layer| ≤ 3μm There are cases where the stiffness (BR) of the transparent conductive film can be adjusted by setting a thickness difference between the functional layer and the cured resin layer. Furthermore, it can more effectively exhibit various properties such as pen glide durability. Additionally, it can further improve the adaptability of input strength. Furthermore, the particle mass per unit volume of the hardened resin layer and the particle mass per unit volume of the functional layer are preferably different.

[0079] 6. Easy-adhesive layer The easy-adhesive layer is preferably formed from a composition containing a carbamate resin, a crosslinking agent, and a polyester resin. As the crosslinking agent, a block isocyanate is preferred, more preferably a block isocyanate with three or more functional groups, and especially preferably a block isocyanate with four or more functional groups. The thickness of the easy-adhesive layer is preferably 0.001 μm to 2.00 μm.

[0080] This application claims priority based on Japanese Patent Application No. 2021-103501, filed on June 22, 2021. The entire contents of the description of Japanese Patent Application No. 2021-103501, filed on June 22, 2021, are incorporated herein by reference. [Example]

[0081] The present invention will be further described in detail below with reference to examples, but the present invention is not limited to these examples at all. Furthermore, the various measurements and evaluations in the examples are performed by the methods described below.

[0082] 1. Measurement and Evaluation (1) Average particle size of silicon oxide particles The cross-section of the transparent conductive film was observed using a scanning electron microscope (Keyence, VE-8800). Fifty particles were randomly selected, and their individual particle sizes were observed. Then, the observed 50 particles were grouped by particle size intervals of 0.020 μm, and the total number of particles in each interval was calculated, resulting in a histogram as follows: the vertical axis represents the number of particles, and the horizontal axis represents the particle size at the 0.020 μm interval scale. For particles whose particle size is within ±30% of the absolute value of the center value of the interval from which the peak of the normal distribution pattern is obtained from the histogram, the average number of observed particle sizes is taken as the average particle size. For example, if there are two peaks of the normal distribution pattern in the histogram, it indicates the addition of two types of particles, and the two average particle sizes are calculated using the same method as described above.

[0083] (2) Thickness of the hardened resin layer and the thickness of the functional layer The thickness of the cured resin layer was determined using the following method: a cross-section of the transparent conductive film was observed using a scanning electron microscope (Keyence, VE-8800), and five arbitrary points were observed; the average value was taken as the thickness. The same method was used for the thickness of the functional layer.

[0084] (3) The tin oxide content in the transparent conductive film Cut a sample (approximately 15 cm²) and place it in a quartz Erlenmeyer flask. Add 20 ml of 6 mol / L hydrochloric acid and seal the flask with a film seal to prevent acid evaporation. Let the flask stand at room temperature for 9 days, shaking occasionally, to allow the transparent conductive film to dissolve. Remove the remaining film and use the hydrochloric acid solution containing the dissolved film as the assay solution. The In and Sn concentrations in the solution were determined using an ICP-C luminescence analyzer (manufacturer: Rigaku, model: CIROS-120 EOP) via a calibration curve method. The wavelengths selected for each element were chosen for their interference-free and high sensitivity. Furthermore, the standard solutions were prepared by diluting commercially available In and Sn standard solutions.

[0085] (4) Thickness of transparent conductive film A 1mm × 10mm section of a thin film sample with a laminated transparent conductive film was cut and embedded in epoxy resin for an electron microscope. This section was then fixed to the sample holder of a microtome, and a thin section parallel to the short side of the embedded sample was prepared. Next, the film thickness was determined from photographs taken using a transmission electron microscope (JEOL, JEM-2010) at an accelerating voltage of 200kV, under bright field conditions, and at a magnification of 10,000x in an undamaged area of ​​this section.

[0086] (5) Crystallinity of transparent conductive film A 1mm × 10mm section of the thin film sample with the transparent conductive film laminated was cut and attached to a suitable resin block with the conductive film side facing out. After trimming, an ultrathin section almost parallel to the film surface was prepared using a standard microtome technique. This section was observed using a transmission electron microscope (JEOL, JEM-2010). The portion of the conductive film surface without obvious damage was selected and photographed at an accelerating voltage of 200kV and a direct magnification of 40,000x. The proportion of crystal grains observed under the transmission electron microscope, i.e., the degree of crystallinity, was observed as an evaluation of the crystallinity of the transparent conductive film.

[0087] (6) Total light transmittance (%) Total light transmittance was measured using NDH-2000 manufactured by Nippon Denshoku Kogyo Co., Ltd., according to JIS-K7361-1:1997. (7) Surface resistance The determination was performed according to JIS-K7194:1994, using the four-terminal method. The measuring instrument used was a Lotesta AX MCP-T370 manufactured by Mitsubishi Chemical Analytech Co., Ltd.

[0088] (8) Adhesion test Performed according to JIS K5600-5-6:1999. The results in the table below express adhesion as a residual area percentage (%). The maximum residual area percentage is 100%. The closer the residual area percentage of the adhesion test in the table is to 100%, the smaller the peeling area.

[0089] (9) Stiffness-softness (BR) (Test Method 3) A 20mm × 250mm test piece is taken from a transparent conductive film and placed on a smooth horizontal platform with the transparent conductive film facing upwards. Only a 20mm × 20mm portion of the test piece is placed on the platform, with a 20mm × 230mm portion protruding horizontally from the end of the platform. Weights are placed on the 20mm × 20mm portion of the test piece, and the weight and size of the weights are selected such that no gap is formed between the test piece and the platform. Next, the difference (δ) between the height of the platform and the height of the front end of the film is read using a ruler. The stiffness is calculated by substituting this value into the following formula. Stiffness / softness BR (N.cm) = g × a × b × L 4 / (8 × δ × 10 11) (In the formula, g is 9.81 (gravitational acceleration; m / s²), a is 20 (length of the short side of the test piece; mm), b represents the specific gravity of the test piece (g / cm³), L is 230 (length of the long side of the test piece protruding from the water platform; mm), and δ represents the difference between the height of the front end of the test piece and the height of the water platform (cm)) The specific gravity b mentioned above was determined using the following method. A transparent conductive film was cut into 5.0 cm squares. Using a micrometer, the total thickness was measured at 10 different locations, with 3 significant figures, and the average thickness (t: μm) was calculated. Using an automatic balance, the weight (w: g) of each 5.0 cm square sample was measured, with 4 significant figures, and the specific gravity was calculated using the following formula. The specific gravity is simplified to 2 significant figures. Specific gravity b (g / cm³) = w / (5.0 × 5.0 × t × 10⁻⁴)

[0090] (10) Maximum mountain height (Sp), average maximum mountain height AVSp (μm) (Test Method 4) The maximum hump height (Sp) (ISO; surface roughness) at five points on the conductive surface of a transparent conductive film is measured, and its arithmetic mean is taken as the average maximum hump height (AVSp). The five points are selected as follows: First, an arbitrary point A is chosen. Then, one point is selected 1 cm upstream and downstream of A along the length (MD) direction of the film, for a total of two points. Next, one point is selected 1 cm to the left and right of A along the width (TD) direction of the film, for a total of two points. The maximum hump height (Sp) (ISO; surface roughness) is as specified in ISO 25178 and is determined using a 3D surface shape measuring device, VertScan (manufactured by Mitsubishi System Co., Ltd., R5500H-M100 (measurement conditions: wave mode, measurement wavelength 560 nm, objective lens 10x)). Furthermore, values ​​less than 1 nm are rounded to the nearest whole number.

[0091] (11) Maximum mountain height upper side displacement ratio (MXSp / AVSp), maximum mountain height lower side displacement ratio (MNSp / AVSp) The ratio of the maximum value MXSp to the average value AVSp of the maximum mountain height Sp obtained by the aforementioned test method 4 is set as the maximum mountain height upper displacement rate (MXSp / AVSp). Furthermore, the ratio (MNSp / AVSp) of the minimum value MNSp and the average value AVSp of the maximum mountain height Sp obtained by the aforementioned test method 4 is set as the displacement rate of the lower side of the maximum mountain height.

[0092] (12) Contact area ratio CA (%), average height Rc (μm), maximum mountain height Rp (μm), average length Rsm (μm), arithmetic mean height Ra (μm) (Test Method 5) For the conductive surface of a transparent conductive film, the average height Rc (μm), maximum peak height Rp (μm), and average length Rsm (μm) based on line roughness are measured. In cases where at least one of equations (X1) and (X2) and equation (X3) is satisfied, the arithmetic mean height Ra (μm) based on line roughness is also measured. Furthermore, the average height Rc (μm), maximum peak height Rp (μm), average length Rsm (μm), and arithmetic mean height Ra (μm) are determined using a 3D surface shape measuring device, VertScan (manufactured by Mitsubishi System Co., Ltd., R5500H-M100 (measurement conditions: wave mode, measurement wavelength 560nm, objective lens 50x)). Moreover, the determination of the maximum peak height Rp (μm), average length Rsm (μm), and arithmetic mean height Ra (μm) complies with the requirements of JIS B 0601-2001. The measurement length for the arithmetic mean height Ra (μm) is set to be between 100μm and 200μm. Rp-Rc-Ra≦0.20...Equation (X1) (Rp-Rc) / Ra≦5.0...Equation (X2) The objective lens of the aforementioned 3D surface shape measuring device, VertScan, was changed to 10x. Using the same particle resolution as the measuring device, a section was cut in the plane at a height equal to "arithmetic mean height Ra (μm) - 15 × 10⁻³ (μm) - mean height Rc (μm)" from the average surface, and the sum of the cross-sectional areas was calculated. The following value is set as the contact area ratio (CA) (%): the sum of the cross-sectional areas divided by the area of ​​the measuring field of view multiplied by 100.

[0093] (13) Input the start load measurement (Test Method 1) As shown in Figure 6, a transparent conductive film is formed by sputtering a hardened resin layer on the laminated film (the film to be processed) 1 on the central roller 2 onto a target 4 within a mask 3. The target 4 is either a sintered target of indium-tin composite oxide or a sintered target of indium oxide without tin oxide. Electricity is applied at a density of 3 W / cm², and the transparent conductive film is formed by DC magnetron sputtering. The film thickness is controlled by changing the speed at which the film passes over the target. An indium-tin composite oxide conductive film (tin oxide content: 10% by mass) with a thickness of 20 nm was formed on one side of a glass substrate (size: 232 mm × 151 mm) using a sputtering method. Specifically, a 1.1 mm thick glass substrate (size: 232 mm × 151 mm) was placed in a vacuum chamber and evacuated to 1.5 × 10⁻⁴ Pa. Then, argon was introduced after oxygen to bring the total pressure to 0.6 Pa. The oxygen to argon flow rate ratio was set to 0.033. Using a sintering target of indium-tin composite oxide (tin oxide content: 10% by mass), a power density of 3 W / cm² was applied, and a 20 nm thick indium-tin composite oxide conductive film (tin oxide content: 10% by mass) was formed on one side of the glass substrate using DC magnetron sputtering. The film-formed glass substrate was then heated in air at 230 °C for 1 hour. On the surface of a conductive film formed on one side of a glass substrate, epoxy resin (manufactured by Toyobo Co., Ltd., product name: CR-102C-23) dots (60μm vertical × 60μm horizontal × 5μm high) are formed into a square grid with a spacing of 4mm (ITO glass substrate). Starting from any one of the four corners of the ITO glass substrate, double-sided adhesive tape (thickness: 105μm, width: 6mm) is applied to the transparent conductive film side in a 190mm × 135mm rectangle. On the double-sided adhesive tape applied to the ITO glass substrate, a transparent conductive film (size: 220mm × 135mm) obtained in the example or comparative example is attached, and the conductive films are laminated with each other facing each other. At this time, one short side of the transparent conductive film extends beyond the ITO glass substrate (evaluation panel). The ITO glass substrate and transparent conductive film of the obtained evaluation panel were connected using a testing machine. From the transparent conductive film side, a load was continuously applied using a polyacetal pen (manufactured by Toray Plastics, Inc., trade name: TPS (registered trademark) POM(NC), tip shape: 0.8mmR), and the load value at which the resistance value measured by the testing machine stabilized was set as the input start load. The location 12 where the pen applies the load is shown in the enlarged view of Figure 7, and is set as the central area of ​​the four dot-shaped gaps 11 arranged in a grid pattern on the surface of the ITO glass substrate 10. Furthermore, the starting load is calculated by averaging the values ​​of any three points at least 50 mm away from the double-sided tape. The first decimal place is rounded. Furthermore, another evaluation panel was created using the same method as described above to determine the initial input load. When rounding to the first decimal place, if the two initial input loads are the same, the initial input load is evaluated as stable, and a value is displayed in Table 6. Conversely, if the two initial input loads are different, the two results are displayed in Table 6.

[0094] (14) Voltage drop time measurement (Test Method 2) The evaluation panel, created during the initial load measurement, was connected to a constant voltage power supply. Next, a recorder (Keyence, GR-7000) capable of measuring the voltage of the ITO glass substrate and the transparent conductive film was connected. Here, the recorder was used to observe the voltage change over time. Next, 6V was applied to the constant voltage power supply, and the voltage was measured using the recorder in 0.02 millisecond increments. Then, from the transparent conductive film side, a 50g load was applied using a polyacetal pen (Toray Plastics, Inc., trade name: TPS (registered trademark) POM(NC), tip shape: 0.8mmR) at a rate of 5 times per second. The position where the pen applied the load was near the center of the evaluation panel, in the center area of ​​the four dot-shaped gaps arranged in a grid pattern. Data on the voltage change over time when the pen applied the load to the transparent conductive film was recorded from the recorder. The time from when the voltage began to decrease from 6V when the pen left the transparent conductive film to when the voltage reached 5V was measured and recorded as the voltage loss time (see Figure 5).

[0095] (15) Adaptive Input Strength Test (Error Input Prevention, Comfort Input) The resistive film touch panel was fabricated using the transparent conductive film obtained in the examples and comparative examples. Input intensity was investigated using a polyacetal pen (manufactured by Toray Plastics, Inc., trade name: TPS (registered trademark) POM(NC), tip shape: 0.8mmR). (Error input prevention) ○...There is less input when touching the touch panel while feeling hesitant. ×…There is a lot of input when touching the touch panel while feeling hesitant. (Comfortable Input) ○…It is possible to input even without consciously applying pressure. △...The behavior is unstable. If no force is applied consciously, input may fail.

[0096] (16) Input stability (stability of the downward stroke, speed of writing) A resistive touch panel was fabricated using the transparent conductive film obtained in the examples and comparative examples. Input stability was investigated using a polyacetal pen. (Stability of the downward stroke) ○…When inputting text, the stroke part of the downward stroke is difficult to blur. When typing text, the strokes of the "×" shape tend to become blurry. (Fast writing ability) ○…When typing continuously, it is difficult for the text to become blurry. When typing text continuously, the text may become blurry.

[0097] (17) Pen glide durability (Test Method 6) A transparent conductive film was used as one side panel. A 20 nm thick indium-tin composite oxide film (tin oxide content: 10% by mass) was formed on one side of a glass substrate using sputtering, serving as the other side panel. Specifically, the fabrication of the other side panel involved immersing a 1.1 mm thick glass substrate (5 cm × 6 cm) in a vacuum chamber and evacuating it to 1.5 × 10⁻⁴ Pa. Then, argon was introduced after oxygen, bringing the total pressure to 0.6 Pa. The oxygen-to-argon flow ratio was set to 0.033. Using a sintering target of indium-tin composite oxide (tin oxide content: 10% by mass), an electric current was applied at a power density of 3 W / cm², and a 20 nm thick indium-tin composite oxide conductive film (tin oxide content: 10% by mass) was formed on one side of the glass substrate using DC magnetron sputtering. The film-formed glass substrate was then heated in air at 230°C for 1 hour. As shown in FIG8, epoxy resin (manufactured by Toyobo Co., Ltd., product name: CR-102C-23) beads (30μm in diameter) are formed into a square grid pattern with a spacing of 4mm on the surface of a conductive film formed on one side of a glass substrate (ITO glass substrate). The transparent conductive film (size: 5cm × 6cm) obtained in the example or comparative example and the ITO glass substrate are overlapped with the transparent conductive film facing each other. During the overlap, as shown in FIG9, the longitudinal directions of the transparent conductive film 20 and the ITO glass substrate 10 are orthogonal, and their respective endpoints 16 are aligned. The longitudinal end 18 of the transparent conductive film 20 and the longitudinal end 17 of the ITO glass substrate 10 extend beyond the overlapping surface 19, and the extended portions 17 and 18 are respectively connected to a testing machine. Next, a 2.5N load was applied to a polyacetal pen (manufactured by Toray Plastics Precision Co., Ltd., trade name: TPS (registered trademark) POM(NC), tip shape: 0.8mmR), and a linear sliding test of 50,000 cycles was performed on the touch panel. The sliding distance was set to 30mm, and the sliding speed to 180mm / s. The sliding position 21, as shown in the enlarged view in Figure 8, was between grid-like dot-shaped gaps 11 arranged on the surface of the ITO glass substrate 10. After this sliding durability test, the ON resistance (resistance value when the movable electrode (thin film electrode) and the fixed electrode are in contact) was measured when the sliding part was pressed with a 0.8N pen load. Ideally, the ON resistance should be below 10kΩ.

[0098] 2. Laminated thin films In the example section, a laminated film comprising a transparent plastic film substrate, a curable resin layer, and a functional layer is used. (1) Substrate (transparent plastic film substrate): biaxially aligned transparent PET film with easy-bonding layers on both sides (manufactured by Toyobo Co., Ltd., A4380, thickness is listed in Table 1).

[0099] (2) Curing Resin Layer: In 100 parts by weight (solid content) of acrylic resin containing a photopolymerization initiator (manufactured by Daihatsu Seiki Co., Ltd., SEIKABEAM (registered trademark) EXF-01J), silicon oxide particles (particle A, particle B) with an average particle size as shown in Table 1 are incorporated in the amounts listed in Table 1. The amount of particles added as shown in Table 1 represents the amount relative to 100% by weight of the solid content of the resin. A mixed solvent of toluene / methyl ethyl ketone (MEK) (8 / 2: mass ratio) is added to achieve the solid content concentration values ​​shown in Table 1, and stirred to uniformly disperse the solvent to prepare a coating solution (coating solution A). The prepared coating solution A is applied to one side of a transparent plastic film substrate using a Myer bar, with the coating thickness as shown in Table 1. After drying at 80°C for 1 minute, the coating is irradiated with ultraviolet light (300 mJ / cm²) using an ultraviolet irradiation device (Eyegraphics, UB042-5AM-W type) to harden the coating.

[0100] (3) Functional Layer: Silicon oxide particles (particle C) with an average particle size as listed in Table 2 are incorporated into 100 parts by weight (solid content) of an acrylic resin containing a photopolymerization initiator (manufactured by Daihsei Chemical Co., Ltd., SEIKABEAM (registered trademark) EXF-01J). The amount of particles added as listed in Table 2 represents the amount relative to 100% by weight of the solid content of the resin. A toluene / MEK (8 / 2: mass ratio) mixed solvent is added as a solvent, with the solid content concentration as shown in Table 2, and the mixture is stirred to uniformly disperse the particles, thus preparing a coating liquid (coating liquid C). The prepared coating liquid C is applied to the side of a transparent plastic film substrate opposite to the aforementioned curable resin layer using a Melt rod, with the coating thickness as shown in Table 2. After drying at 80°C for 1 minute, the coating is irradiated with ultraviolet light (300 mJ / cm²) using an ultraviolet irradiation device (Eyegraphics, UB042-5AM-W type) to harden the coating.

[0101] Examples 1-8 The laminated film was placed in a vacuum chamber and evacuated to 1.5 × 10⁻⁴ Pa. Then, argon was introduced after oxygen to bring the total pressure to 0.6 Pa. The flow rates of oxygen and argon are shown in Table 3. As shown in Figure 6, a transparent conductive film is formed by sputtering a hardened resin layer on the laminated film (the film to be processed) 1 on the central roller 2 onto a target 4 within a mask 3. The target 4 is either a sintered target of indium-tin composite oxide or a sintered target of indium oxide without tin oxide. Electricity is applied at a density of 3 W / cm², and the transparent conductive film is formed by DC magnetron sputtering. The film thickness is controlled by changing the speed at which the film passes over the target. Furthermore, the partial pressure ratio of water to inactive gas in the film-forming gas environment during sputtering was measured using a gas analyzer (Inficon, Transpector XPR3), and is shown in Table 3. This water ratio, as described in Table 3, was adjusted based on the presence or absence of a bombardment step, the presence or absence of a protective film, the unevenness of the film roll end face, and the temperature of the temperature control medium in the temperature control unit used to control the temperature of the center roller during film contact. In the aforementioned bombardment step, RF sputtering was performed at 0.5 W / cm² using SUS (stainless steel) as the target. The amount of gas introduced for RF sputtering was set to be the same as the amount described in the embodiment of the vacuum device. When using a protective film, a 65 μm thick polyethylene film was used. An acrylic adhesive was coated on one side of the protective film. The protective film was attached to the opposite side of the laminated film, opposite to the side forming the transparent conductive film. The temperature of the aforementioned temperature control medium was the value recorded in Table 3, which corresponds to the midpoint between the maximum and minimum temperatures from the start of film formation to the end of film formation. A transparent conductive film was obtained by applying the heat treatment shown in Table 3 to the film with the deposited transparent conductive film. For the obtained transparent conductive film, the film thickness, crystallinity, total light transmittance (%), surface resistivity (Ω / □), adhesion to the transparent conductive film, and adhesion to the functional layer were evaluated. The results are shown in Table 4.

[0102] For the obtained transparent conductive film, the stiffness-softness ratio (BR), average maximum peak height (AVSp), contact area ratio (CA), maximum peak height upper displacement ratio (MXSp / AVSp), and maximum peak height lower displacement ratio (MNSp / AVSp) were calculated. The results are shown in Table 5.

[0103] For the obtained transparent conductive film, the following were investigated: input onset load, voltage drop time, suitable input strength test (error input prevention, comfortable input), input stability (stroke stability, fast writing), and pen glide durability. The results are shown in Table 6.

[0104] Comparative Examples 1-8 In addition to using the laminated films prepared under the conditions shown in Tables 1 and 2, and forming transparent conductive films under the conditions shown in Table 3, transparent conductive films were prepared in the same manner as in Examples 1 to 8. The properties of the obtained films are shown in Tables 4 to 6.

[0105] [Table 1] Substrate hardened resin layer thickness (μm) Does it exist or not? Hardened type resin layer Particle A Added amount (wt%) Particle B Added amount (wt%) Particle A Particle size (μm) Particle B Particle size (μm) Solid component concentration (%) thickness (μm) Example 1 188 have 5 9 1.00 0.30 47 6.0 Example 2 188 have none 1 - 0.10 45 5.0 Example 3 125 have none 15 - 0.05 45 6.0 Example 4 250 have 4 4 0.40 0.20 50 3.0 Example 5 250 have 3 11 1.80 0.70 55 5.0 Example 6 188 have none 10 - 0.40 55 15.0 Example 7 188 have 3 5 0.70 0.40 60 4.0 Example 8 188 have none 9 - 0.10 55 15.0 Comparative Example 1 188 have None 27 - 0.60 45 5.0 Comparative Example 2 100 Yes None 40 - 0.10 45 15.0 Comparative Example 3 300 None - - - - - - - Comparative Example 4 250 Yes 4 11 2.00 0.70 58 5.0 Comparative Example 5 188 Yes - 30 - 0.60 65 4.0 Comparative Example 6 188 Yes None 35 - 0.10 45 9.0 Comparative Example 7 188 have 5 9 1.00 0.40 60 4.0 Comparative Example 8 250 none - - - - - - -

[0106] [Table 2] Functional layer Does it exist or not? Functional layer Particle C Added amount (Wt%) Particle C Particle size (μm) Solid component concentration (%) thickness (μm) Example 1 have 15.0 3.00 50 3.0 Example 2 have 15.0 3.00 50 3.0 Example 3 have 20.0 3.00 50 4.0 Example 4 have 1.0 3.00 50 3.0 Example 5 have 5.0 3.00 50 6.0 Example 6 have 1.0 3.00 50 11.0 Example 7 have 15.0 3.00 50 6.0 Example 8 have 1.0 3.00 50 11.0 Comparative Example 1 have 28.0 3.00 50 6.0 Comparative Example 2 have 27.0 3.00 55 10.0 Comparative Example 3 have 1.0 3.00 50 4.0 Comparative Example 4 have 7.0 3.00 50 9.0 Comparative Example 5 have 15.0 3.00 50 1.0 Comparative Example 6 have 15.0 3.00 43 5.0 Comparative Example 7 have 10.0 3.00 60 2.0 Comparative Example 8 none - - - -

[0107] [Table 3] Transparent conductive film formation conditions Oxygen / Ar Flow ratio Water / Ar partial pressure ratio (×10 -3) Roller temperature (°C) bombardment steps Protective film film roll end face Concave and convex height difference (mm) Tin oxide content (wt%) Heat treatment Example 1 0.049 1.40 -12 have have 2 3 150℃ for 60 minutes Example 2 0.049 1.40 -12 have have 2 3 150℃ for 60 minutes Example 3 0.049 1.40 -12 have have 2 3 150℃ for 60 minutes Example 4 0.041 1.40 -12 have have 2 36 150℃ for 60 minutes Example 5 0.046 1.30 -12 have have 2 10 150℃ for 60 minutes Example 6 0.041 6.90 0 have have 9 36 150℃ for 60 minutes Example 7 0.042 0.55 -12 have have 5 1 165℃ for 75 minutes Example 8 0.008 0.80 -12 have have 2 36 150℃ for 60 minutes Comparative Example 1 0.041 1.40 -12 have have 2 36 150℃ for 60 minutes Comparative Example 2 0.049 1.10 -12 have have 2 3 150℃ for 60 minutes Comparative Example 3 0.049 1.70 -12 have have 2 3 150℃ for 60 minutes Comparative Example 4 0.049 1.80 -12 have have 2 3 150℃ for 60 minutes Comparative Example 5 0.049 8.20 2 none none 11 36 150℃ for 60 minutes Comparative Example 6 0.008 0.80 -12 have have 2 0 80℃ for 20 minutes Comparative Example 7 0.049 1.40 -12 have have 2 3 150℃ for 60 minutes Comparative Example 8 0.049 1.70 -12 have have 2 45 150℃ for 60 minutes

[0108] [Table 4] Transparent conductive film (1) transparent conductive film Film thickness (nm) Degree of crystallinity (%) Total light transmittance (%) Surface resistance (Ω / □) Transparent guide electric layer Adhesion test (%) Functional layer Attachment Sexual experiment (%) Example 1 twenty three 100 87 450 100 100 Example 2 twenty three 100 87 450 100 100 Example 3 twenty three 100 87 450 100 100 Example 4 twenty two 0 86 480 100 100 Example 5 twenty one 0 86.9 250 100 100 Example 6 90 0 81 110 100 100 Example 7 13 70 87.5 570 100 100 Example 8 80 0 82 125 100 100 Comparative Example 1 twenty three 0 87 450 100 100 Comparative Example 2 twenty three 100 87 450 100 100 Comparative Example 3 twenty three 100 87 450 10 100 Comparative Example 4 twenty three 100 87 450 100 100 Comparative Example 5 8 0 88 1200 100 100 Comparative Example 6 110 100 68 1700 100 100 Comparative Example 7 twenty three 100 87 450 100 100 Comparative Example 8 twenty three 0 87 600 10 -

[0109] [Table 5] Stiffness BR Average maximum mountain height AVSp (μm) Contact area ratio CA (%) Maximum mountain height Upper displacement rate MXSp / AvSp Maximum mountain height Lower displacement rate MNSp / AVSp Stiffness BR (N･cm) Equation (2-1) left (A1) Equation (2-1) right (A2) Equation (2-3) right (A3) Example 1 0.65 -0.545 1.255 38.4 1.236 41.3 1.24 0.76 Example 2 0.61 -0.733 1.067 37.1 0.053 92.1 1.13 0.83 Example 3 0.39 -1.767 0.033 29.9 0.030 94.9 1.10 0.87 Example 4 0.87 0.489 2.289 45.6 0.510 63.7 1.18 0.80 Example 5 0.89 0.583 2.383 46.2 2.350 48.0 1.32 0.64 Example 6 0.83 0.301 2.101 44.3 0.521 52.0 1.19 0.81 Example 7 0.57 -0.921 0.879 35.8 0.852 55.3 1.21 0.79 Example 8 0.78 0.066 1.866 42.6 0.077 88.2 1.19 0.77 Comparative Example 1 0.58 -0.869 0.931 36.1 0.694 35.3 1.20 0.81 Comparative Example 2 0.35 -1.941 -0.141 28.7 0.257 77.4 1.17 0.82 Comparative Example 3 0.95 0.865 2.665 48.2 0.004 100.0 1.25 0.75 Comparative Example 4 0.89 0.583 2.383 46.2 2.598 44.2 1.35 0.63 Comparative Example 5 0.66 -0.498 1.302 38.7 0.743 34.8 1.43 0.58 Comparative Example 6 0.80 0.160 1.960 43.3 0.149 82.1 1.14 0.84 Comparative Example 7 0.63 -0.639 1.161 37.7 1.425 34.4 1.27 0.72 Comparative Example 8 0.91 0.677 2.477 46.9 0.004 100.0 1.25 0.75

[0110] [Table 6] enter start load (g) Voltage loss time (ms) Incorrect input Preventive Comfort Input The stroke of the right-hand stroke stability fast writing Pen slide Durability (Resistance (kΩ)) Example 1 16 0.38 ○ ○ ○ ○ 0.1 Example 2 twenty one 0.12 ○ ○ ○ ○ 0.1 Example 3 16 0.07 ○ ○ ○ ○ 0.1 Example 4 25 0.27 ○ ○ ○ ○ 9 Example 5 16 0.39 ○ ○ ○ ○ 8 Example 6 twenty three 0.39 ○ ○ ○ ○ 2 Example 7 16 0.25 ○ ○ ○ ○ 0.3 Example 8 25 0.14 ○ ○ ○ ○ 3 Comparative Example 1 17 0.43 ○ ○ × × 8 Comparative Example 2 15 0.15 × ○ ○ ○ 0.8 Comparative Example 3 37 0.13 ○ × ○ ○ ∞ Comparative Example 4 15 0.45 × ○ × × 0.1 Comparative Example 5 18, 20 There are variations 0.41 ○ △ × × 15 Comparative Example 6 26 0.18 ○ × ○ ○ 0.1 Comparative Example 7 14 0.42 × ○ × × 0.1 Comparative Example 8 34 0.07 ○ × ○ ○ ∞ [Potential for industrial application]

[0111] Transparent conductive films are widely used in the electrical and electronic fields as transparent electrodes for flat panel displays such as liquid crystal displays and electroluminescent (EL) displays, as well as touch panels.

[0112] 1: The film being processed 2: Center Roller 3: Mask 4: Target 5: Transparent conductive film 6: Curing resin layer 7: Transparent plastic film substrate 8: Functional Layer 9: Easy-adhesive layer 10: ITO glass substrate 11: Point-like interstitial structures 12: The position where the pen applies the load 13: Time 14: Voltage 15: Voltage drop time 16: Endpoint 17, 18: Exceeding the limit 19: Overlapping surfaces 20: Transparent conductive film 21: The position for sliding

Claims

1. A transparent conductive film, comprising a transparent conductive film having at least one area layer of indium-tin composite oxide on a transparent plastic film substrate, wherein the input initial load determined by test method 1 is greater than 15g and less than 25g; the voltage drop time determined by test method 2 is greater than 0.00 ms and less than 0.40 ms; the film stiffness (BR) determined by test method 3 is greater than 0.38 N·cm and less than 0.90 N·cm; the average of the maximum peak height Sp of the conductive surface (AVSp) determined by test method 4 satisfies the following formula (2-1); and the contact area ratio (CA) determined by test method 5 satisfies the following formula (2-3): 4.7×BR-3.6≦AVSp<4.7×BR-1.8... Formula (2-1) CA≧32.6×BR+17.2... Equation (2-3) (where BR is the stiffness of the thin film (N·cm), AVSp is the average maximum height (μm), and CA is the contact area ratio (%)) [Test Method 1] An indium-tin composite oxide conductive film with a thickness of 20nm (tin oxide content: 10% by mass) is formed on one side of a glass substrate. On the surface of this film, epoxy resin dot-shaped interstices (60μm in length × 60μm in width × 5μm in height) are formed into a square grid at a spacing of 4mm to serve as a panel. On the conductive film side of this panel, a rectangular frame with an adhesion of 105μm thickness and an inner circumference of 190mm × 135mm is sandwiched between them. At the same time, a transparent conductive film is overlapped with the conductive films facing each other to make an evaluation panel. From the transparent conductive film side of this evaluation panel, a pen with a hemispherical tip of 0.8mm radius is used to continuously press the center of the 4-dot grid of the dot-shaped interstices. The pressure at which the resistance value begins to stabilize is set as the input starting load. [Test Method 2] Connect the evaluation panel to a constant voltage power supply of 6V. Using a pen with a hemispherical tip and a radius of 0.8mm, press the center of the 4-point grid of the dotted gap at intervals of 5 times / second with a load of 50gf. The time from when the voltage starts to decrease from 6V when the pen leaves the transparent conductive film to when the voltage becomes 5V is measured and is set as the voltage loss time. [Test Method 3] Place a 20mm×250mm transparent conductive film test piece on a horizontal platform with the transparent conductive film facing upwards, so that the test piece protrudes 230mm from the end of the horizontal platform. Determine the stiffness (BR) based on the following formula: Stiffness (BR (N·cm)) = g×a×b×L4 / (8×δ×1011) (where g is a constant value of 9.)81 (gravitational acceleration; m / s2), a represents 20 (length of the short side of the test piece; mm), b represents the specific gravity of the test piece (g / cm3), L represents 230 (length of the long side of the test piece protruding outside the water platform; mm), δ represents the difference between the height of the front end of the test piece and the height of the water platform (cm)) [Test Method 4] On the conductive surface of the transparent conductive film, 3 points are determined at 1 cm intervals in the MD direction, and 2 points are determined symmetrically in the TD direction at 1 cm intervals from its center, for a total of 5 measurement points. The maximum hill height Sp based on the surface roughness is measured at each location (according to ISO 25178), and its average value is set as the average maximum hill height (AVSp) (μm). [Test Method 5] For the conductive surface of a transparent conductive film, the average height Rc (μm), maximum peak height Rp (μm), and average length Rsm (μm) based on line roughness are measured. In locations satisfying at least one of equations (X1) and (X2) and equation (X3), the arithmetic mean height Ra (μm) based on line roughness is measured. Furthermore, the average height Rc (μm), maximum peak height Rp (μm), average length Rsm (μm), and arithmetic mean height Ra (μm) are determined using a 3D surface shape measuring device, VertScan (manufactured by Mitsubishi System Co., Ltd., R5500H-M100 (measurement conditions: wave mode, measurement wavelength 560nm, objective lens 50x)). The determination of the maximum peak height Rp (μm), average length Rsm (μm), and arithmetic mean height Ra (μm) follows JIS B. According to the 0601-2001 standard, the measurement length for the arithmetic mean height Ra (μm) is set to be between 100μm and 200μm, with Rp-Rc-Ra≦0.20... Equation (X1) (Rp-Rc) / Ra≦5.0... Equation (X2) Rsm≦30... Equation (X3) The objective lens of the VertScan 3D surface shape measuring device is changed to 10x. Using the same particle resolution as the measuring device, a slice is taken in the planar direction at a height of "arithmetic mean height Ra (μm) - 15 × 10⁻³ (μm) - average height Rc (μm)" from the average surface. The sum of the cross-sectional areas is calculated, and the following value is set as the contact area ratio (CA) (%): the sum of the cross-sectional areas divided by the area of ​​the measurement field of view multiplied by 100.

2. The transparent conductive film of claim 1, wherein the average (AVSp) of the maximum peak height Sp of the conductive surface determined by the test method 4 satisfies the following formula (2-2): 0.005≦AVSp≦12.000... Formula (2-2) (where AVSp is the average maximum peak height (μm)).

3. The transparent conductive film of claim 1, wherein the maximum value MXSp of the maximum height Sp determined by the test method 4 is more than 1.0 times and less than 1.4 times the average maximum height AVSp, and the minimum value MNSp of the maximum height Sp determined by the test method 4 is more than 0.6 times and less than 1.0 times the average maximum height AVSp.

4. A transparent conductive film as claimed in any one of claims 1 to 3, wherein the thickness of the transparent conductive film is more than 10 nm and less than 100 nm.

5. A transparent conductive film as claimed in any one of claims 1 to 3, wherein the concentration of tin oxide contained in the transparent conductive film is more than 0.5% by mass and less than 40% by mass.

6. A transparent conductive film as claimed in any one of claims 1 to 3, wherein a curable resin layer is provided between the transparent conductive film and the transparent plastic film substrate, and further wherein a functional layer is provided on the side of the transparent plastic film substrate opposite to the transparent conductive film.

7. A transparent conductive film as claimed in any one of claims 1 to 3, wherein an easy-adhesion layer is provided on at least one side of the transparent plastic film substrate.

8. The transparent conductive film of claim 6, wherein an easy-adhesion layer is provided on at least one side of the transparent plastic film substrate, the easy-adhesion layer being disposed at at least one location between the transparent plastic film substrate and the curing resin layer, or between the transparent plastic film substrate and the functional layer.

9. A transparent conductive film of any one of claims 1 to 3, wherein the ON resistance as specified in Test Method 6 is 10kΩ or less, [Test Method 6] An evaluation panel is made by overlapping an indium-tin composite oxide conductive film (tin oxide content: 10% by mass) with the conductive films facing each other on one side of a glass substrate, with epoxy beads of 30μm diameter as a barrier, to form a panel with a thickness of 20nm and a transparent conductive film. On the transparent conductive film side of this evaluation panel, a pen with a hemispherical polyacetal tip of 0.8mm radius is used to apply a load of 2.5N while sliding (50,000 back-and-forth strokes, sliding distance of 30mm, sliding speed of 180mm / s). After sliding, the sliding part is pressed with a pen load of 0.8N, and the resistance (ON resistance) when electrically connected is measured.

10. A transparent conductive film as claimed in any one of claims 1 to 3, wherein, in an adhesion test according to JIS K5600-5-6:1999, the residual area of ​​the transparent conductive film on the surface of the transparent conductive film is more than 95%.

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