Transparent conductive film

Abstract

The present invention aims to provide a transparent conductive film which is excellent in input strength and input stability. The transparent conductive film of the present invention is a transparent conductive film in which an indium-tin composite oxide transparent conductive film is laminated on at least one side of a transparent plastic film substrate, the input start load is greater than 15 g and is 25 g or less, and the voltage loss time is 0.00 msec or more and 0.40 msec or less. The film stiffness (BR) is 0.38 N·cm or more and 0.90 N·cm or less, and the average value (AVSp) of the maximum peak height Sp of the conductive surface preferably satisfies the following formula (2-1). 4.7×BR−3.6≤AVSp<4.7×BR−1.8…Formula (2-1) (in the formula, BR is the film stiffness (N·cm), and AVSp is the average maximum peak height (μm)).

Description

TECHNICAL FIELD

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

[0002] A transparent conductive film in which a thin film that is transparent and has a small electric resistance is layered on a transparent plastic substrate is widely used for uses that utilize its conductivity, for example, as a transparent electrode of a flat panel display such as a liquid crystal display, an electroluminescence (EL) display, and the like, a touch panel, and the like, and is widely used for uses in the electric and electronic fields.

[0003] An electric resistance film type touch panel is one in which a fixed electrode in which a transparent conductive thin film is coated on a substrate of glass or plastic, and a movable electrode (referred to as a film electrode) in which a transparent conductive thin film is coated on a plastic film are combined, and are used by being overlaid on the upper side of a display body. If the film electrode is pressed with a finger or a pen (referred to as input), the transparent conductive thin films of the fixed electrode and the film electrode come into contact with each other, and thus the input position is recognized.

[0004] A transparent conductive layering body for a touch panel is disclosed in Patent Literature 1, which is one in which a transparent conductive film formed of substantially only crystalline indium oxide is layered on at least one surface of a polymer film. By crystallizing the indium oxide, the durability against a pen is improved.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT LITERATURE

[0007] Patent Literature 1: Japanese Patent Application Laid-Open No. 2004-071171 SUMMARY

[0008] PROBLEMS TO BE SOLVED BY THE INVENTION

[0009] For a touch panel, a characteristic (pen slide durability) is required in which even if a pen is continuously input, a crack, peeling, abrasion, and the like do not occur in the transparent conductive film.

[0010] Furthermore, for touch panels, a suitable range of input strength (adaptive input strength) is required. For example, in resistive touch panels, when the fixed electrode and the transparent conductive film of the membrane electrode come into contact with each other by pressing the membrane electrode with a finger or pen, accidental touches may occur from the hand or sleeve of clothing. Sometimes, due to confusion about the point of contact, the touch panel may be accidentally touched with a pen. It is desirable to minimize input caused by such unintentional contact with the touch panel (mis-input prevention). However, improving mis-input prevention tends to decrease comfortable input. Comfortable input refers to the ability to input with a pen or finger on a resistive touch panel without consciously applying excessive force. A balance must be struck between preventing mis-input and comfortable input.

[0011] Furthermore, for touch panels, excellent input stability is required, meaning stable input from the moment a pen touches the touch panel until it is removed. For example, it is required to reduce text blurring (shorthand quality) that may occur when continuously typing, and to prevent blurring of the strokes (slant strokes) in characters (stroke input quality).

[0012] In the technology of Patent Document 1, pen sliding durability cannot be improved without crystallizing indium oxide. Furthermore, conventional transparent conductive films, including those in Patent Document 1, are insufficient in terms of adaptability to input strength (anti-mistyping, comfortable input) and input stability (quick memorization, stroke / stroke input).

[0013] Therefore, the object of the present invention is to provide a transparent conductive film with excellent adaptive input strength and input stability. Furthermore, a preferred object of the present invention is to provide a transparent conductive film that also possesses pen-slip durability.

[0014] Methods for solving problems

[0015] The present invention was 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, has the following composition. [1]

[0017] A transparent conductive film is a transparent conductive film in which an indium-tin composite oxide transparent conductive film is laminated on at least one side of a transparent plastic film substrate.

[0018] The initial input load determined by test method 1 is greater than 15g and less than 25g.

[0019] The voltage drop time determined by experimental method 2 is greater than 0.00 milliseconds and less than 0.40 milliseconds.

[0020] [Experimental Method 1]

[0021] A panel was produced by forming an indium-tin composite oxide conductive film (tin oxide content: 10 mass%) having a thickness of 20 nm on one side of a glass substrate, and forming dot-shaped spacers (length 60 μm x width 60 μm x height 5 μm) of an epoxy resin in a square lattice pattern at intervals of 4 mm on the surface of the thin film. An evaluation panel was produced by overlapping a transparent conductive film on the conductive film side of the panel while sandwiching a rectangular frame having an adhesive property having a thickness of 105 μm and an inner circumference of 190 mm x 135 mm, in such a manner that the conductive films faced each other. The pressure at which the resistance value became stable was taken as the input start load, by pressing the center of the 4-dot lattice of the dot-shaped spacers from the transparent conductive film side of the evaluation panel with a pen having a hemispherical tip with a radius of 0.8 mm.

[0022] [Experimental Method 2]

[0023] The above evaluation panel was connected to a constant voltage power supply of 6 V, and the center of the 4-dot lattice of the dot-shaped spacers was pressed from the transparent conductive film side at an interval of 5 times / second with a load of 50 gf using a pen having a hemispherical tip with a radius of 0.8 mm. The time until the voltage reached 5 V was measured as the voltage loss time, starting from when the pen began to move away from the transparent conductive film and the voltage began to decrease from 6 V. [2]

[0025] The film stiffness (BR) of the transparent conductive film described in [1] was 0.38 N-cm or more and 0.90 N-cm or less, which was found by Experimental Method 3,

[0026] The average value (AVSp) of the maximum peak height Sp of the conductive surface, which was found by Experimental Method 4, satisfied the following Equations (2-1) and (2-2),

[0027] The contact area ratio (CA) found by Experimental Method 5 satisfied the following Equation (2-3).

[0028] 4.7 x BR - 3.6 ≤ AVSp < 4.7 x BR - 1.8... Equation (2-1)

[0029] 0.005 ≤ AVSp ≤ 12.000... Equation (2-2)

[0030] CA ≥ 32.6 x BR + 17.2... Equation (2-3)

[0031] (In the equations, BR is the film stiffness (N-cm), AVSp is the average maximum peak height (μm), and CA is the contact area ratio (%))

[0032] [Experimental Method 3]

[0033] A 20 mm x 250 mm transparent conductive film test piece was placed on a water table with the transparent conductive film facing upward, so that the test piece protruded from the end of the table by a length of 230 mm, and the stiffness (BR) was determined based on the following equation.

[0034] Stiffness (BR (N-cm)) = g x a x b x L 4 / (8 x δ x 10 11 )

[0035] (In the equation, g is 9.81 (acceleration due to gravity; m / s 2 ), a is 20 (length of the short side of the test piece; mm), b represents the specific gravity of the test piece (g / cm 3 ), L is 230 (length of the long side of the test piece exposed outside the water table; mm), and δ represents the difference between the height of the front end of the test piece and the height of the table (cm))

[0036] [TEST METHOD 4]

[0037] In the conductive surface of the transparent conductive film, 3 points were determined at 1 cm intervals in the MD direction, and 2 points were determined at 1 cm intervals from the center in the TD direction symmetrically, for a total of 5 points, the maximum peak height Sp based on the surface roughness (in accordance with ISO 25178) was measured at each position, and the average value thereof was taken as the average maximum peak height (AVSp) (μm).

[0038] [TEST METHOD 5]

[0039] For the conductive surface of the transparent conductive film, the average height Rc (μm), the maximum peak height Rp (μm), and the average length Rsm (μm) based on the line roughness were measured, and the arithmetic average height Ra (μm) based on the line roughness was measured at a site that satisfied at least one of Equation (X1) and Equation (X2) and Equation (X3). Note that the average height Rc (μm), the maximum peak height Rp (μm), the average length Rsm (μm), and the arithmetic average height Ra (μm) were determined using a three-dimensional surface shape measuring device VertScan (manufactured by Ryoka Systems, Inc., R5500H-M100 (measurement conditions: wave mode, measurement wavelength 560 nm, objective lens 50x)). The determination of the maximum peak height Rp (μm), the average length Rsm (μm), and the arithmetic average height Ra (μm) was in accordance with the provisions of JIS B 0601-2001. The measurement length of the arithmetic average height Ra (μm) was set to 100 μm or more and 200 μm or less.

[0040] Rp - Rc - Ra ≤ 0.20... Equation (X1)

[0041] (Rp - Rc) / Ra ≤ 5.0... Equation (X2)

[0042] Rsm≤ 30... Equation (X3)

[0043] The objective lens of the three-dimensional surface shape measuring device VertScan described above was changed to 10 times, and particle analysis based on the measuring device was used to perform slicing in the planar direction at a height of "arithmetic average height Ra (μm) - 15 x 10 -3 The sum of the cross-sectional areas was divided by the area of the measurement field to obtain a value, and the value obtained by multiplying the value by 100 was taken as the contact area ratio (CA) (%). [3]

[0045] According to the transparent conductive film described in [2], a maximum value MXSp of the maximum peak height Sp obtained by the above-described Test Method 4 exceeds 1.0 times and is 1.4 times or less of the above-described average maximum peak height AVSp, and

[0046] A minimum value MNSp of the maximum peak height Sp obtained by the above-described Test Method 4 is 0.6 times or more and 1.0 times or less of the above-described average maximum peak height AVSp. [4]

[0048] According to the transparent conductive film described in any one of [1] to [3], the thickness of the transparent conductive film is 10 nm or more and 100 nm or less. [5]

[0050] According to the transparent conductive film described in any one of [1] to [4], the concentration of tin oxide contained in the transparent conductive film is 0.5 mass% or more and 40 mass% or less. [6]

[0052] According to the transparent conductive film described in any one of [1] to [5], a cured resin layer is provided between the transparent conductive film and the transparent plastic film substrate,

[0053] Further, a functional layer is provided on the side of the transparent plastic substrate opposite the transparent conductive film. [7]

[0055] According to the transparent conductive film described in any one of [1] to [6], an easy-adhesion layer is provided on at least one side of the transparent plastic film substrate. [8]

[0057] According to the transparent conductive film described in [7], the easy-adhesion layer is provided at least one of between the transparent plastic film substrate and the cured resin layer, or between the transparent plastic substrate and the functional layer. [9]

[0059] The transparent conductive film according to any one of [1] to [8], wherein the ON resistance determined by Test Method 6 is 10 kΩ or less.

[0060] [TEST METHOD 6]

[0061] An evaluation panel was produced by overlapping a panel in which an indium-tin composite oxide conductive film (tin oxide content: 10 mass%) having a thickness of 20 nm was formed on one side of a glass substrate with the transparent conductive film with an epoxy microbead having a diameter of 30 μm in such a manner that the conductive films faced each other. On the side of the transparent conductive film of the evaluation panel, a load of 2.5 N was applied with a pen having a hemispherical tip with a radius of 0.8 mm while sliding (reciprocation number: 50,000 times, sliding distance: 30 mm, sliding speed: 180 mm / sec). After the sliding, the resistance when the sliding portion was pressed with a load of 0.8 N to be electrically connected (ON resistance) was measured.

[10]

[0063] The transparent conductive film according to any one of [1] to [9], wherein 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 95% or more.

[0064] EFFECT OF THE INVENTION

[0065] According to the present application, a transparent conductive film having excellent adaptability of input intensity and input stability can be provided. In addition, according to the present application, in a preferable case, a transparent conductive film further having pen sliding durability can be further provided. BRIEF DESCRIPTION OF DRAWINGS

[0066] Figure 1 is a schematic side view showing one example of the transparent conductive film of the present application.

[0067] Figure 2 is a schematic side view showing another example of the transparent conductive film of the present application.

[0068] Figure 3 is a schematic side view showing still another example of the transparent conductive film of the present application.

[0069] Figure 4 is a schematic side view showing still another example of the transparent conductive film of the present application.

[0070] Figure 5 is a conceptual view showing the relationship between voltage and time in one mode of the present application.

[0071] Figure 6 is a schematic view of an apparatus showing one example of the film forming method of the present application.

[0072] Figure 7 This is a schematic top view enlarged to illustrate the input start load measurement method in this invention.

[0073] Figure 8 This is a schematic top-view enlarged view illustrating the pen sliding durability testing method in this invention.

[0074] Figure 9 This is a schematic top view illustrating the pen sliding durability testing method in this invention. Detailed Implementation

[0075] 1. Transparent conductive film

[0076] The transparent conductive film of the present invention is a transparent conductive film in which an indium-tin composite oxide transparent conductive film is laminated on at least one side of 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 in electrical and electronic fields for flat panel displays like liquid crystal displays and electroluminescent (EL) displays, and touch panels. The specific layer composition of the transparent conductive film can be appropriately set, for example, as exemplified by... Figure 1 , Figure 2 , Figure 3 , Figure 4 The schematic side view of the structure is shown.

[0077] Figure 1 A transparent conductive film 5 is formed on one side of a transparent plastic film substrate 7, separated by a curable resin layer 6, and a functional layer 8 is formed on the opposite side of the transparent plastic film substrate 7. If the curable resin layer 6 is formed 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 adaptive input strength and input stability by controlling the input start load and voltage drop time (described later), and further improves adaptive input strength and input stability by preventing the precipitation of oligomers. Furthermore, by utilizing 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. In addition, by having the curable resin layer 6 and / or the functional layer 8, the stiffness of the transparent conductive film (described later) can be adjusted. It should be noted that the curable resin layer 6 and / or the functional layer 8 are not necessary depending on the rigidity of the transparent plastic film substrate.

[0078] In one embodiment, the transparent conductive film of the present invention has an adhesive layer laminated on at least one side of a transparent plastic film substrate. For example, such as Figure 2 As shown, the cured resin layer 6 and the transparent plastic film substrate 7 can be bonded together using the easy-to-adhere layer 9. For example... Figure 3As shown, the functional layer 8 and the transparent plastic film substrate 7 can be bonded by the easy-adhesive layer 9. As shown Figure 4 As shown, the curable resin layer 6 and the functional layer 8 can each be bonded to the transparent plastic film substrate 7 by the easy-adhesive layer 9. By having the easy-adhesive layer 9, peeling of the curable resin layer 6 and / or the functional layer 8 from the transparent plastic film substrate 7 due to external force can be more effectively suppressed.

[0079] The transparent conductive film of the present application is characterized in that the input start load obtained by Test Method 1 is greater than 15 g and is 25 g or less (Feature 1). By setting the input start load to be a prescribed value or less, the comfortable input property can be improved.

[0080] [TEST METHOD 1]

[0081] A panel was produced by forming an indium-tin composite oxide conductive film (tin oxide content: 10 mass%) having a thickness of 20 nm on one side of a glass substrate, and forming dot-shaped spacers (length 60 μm x width 60 μm x height 5 μm) of an epoxy resin in a square lattice pattern at a pitch of 4 mm on the surface of the thin film. On the conductive film side of the panel, a transparent conductive film was overlaid in such a manner that the conductive films faced each other, with a rectangular frame having an adhesive thickness of 105 μm and an inner circumference of 190 mm x 135 mm interposed, to produce an evaluation panel. The pressure at which the resistance value became stable was measured as the input start load by pressing the center of the 4-dot lattice of the dot-shaped spacers from the transparent conductive film side of the evaluation panel with a pen having a hemispherical tip with a radius of 0.8 mm. Here, the "stable resistance value" refers to, for example, a state in which the resistance value fluctuates within ±5% of the average value.

[0082] In addition, the transparent conductive film described above is further characterized in that the voltage loss time obtained by Test Method 2 is 0.00 milliseconds or more and 0.40 milliseconds or less (Feature 2). By setting the voltage loss time to be within a prescribed range, the contact time in the electrically stable state can be further lengthened. By setting the input start load to be within a prescribed range, the false input prevention property can be improved, and by setting the voltage loss time to be within a prescribed range, the input stability, such as the stroke stability, the shorthand property, and the like, can be improved. The reason for the effects of such input stability is not limited to a specific theory, but it is believed that the reason is that the contact time in the electrically stable state can be further lengthened and the contact state in the electrically unstable state can be further reduced. As a result, the time during which the input is unstable is shortened, and, for example, the text dropout when writing text continuously can be prevented, and the text dropout when taking shorthand can be reduced. In addition, for example, in a touch panel, in the case of writing text, the problem of the text shown on the touch panel being dropped and not displayed can be solved. Thus, the text or pattern, and the like, that is intended to be expressed can be clearly depicted on the resistance film type touch panel. For example, the stroke of the text as expressed by a brush pen can also be expressed.

[0083] The transparent conductive film having the characteristics 1 (input start load) and 2 (voltage loss time) is extremely useful in applications such as a resistance film type touch panel.

[0084] The voltage loss time is preferably 0.39 msec or less, more preferably 0.35 msec or less, and still more preferably 0.30 msec or less, and is more preferably shorter. In addition, the voltage loss time can be 0.01 msec or more, for example, 0.02 msec or more. That is, the voltage loss time is preferably 0.01 to 0.39 msec, more preferably 0.01 to 0.35 msec, and still more preferably 0.02 to 0.30 msec.

[0085] [Test method 2]

[0086] The above evaluation panel was connected to a constant voltage power source of 6 V, and a pen having a semisphere with a radius of 0.8 mm at the tip was pressed at the center of a 4-point lattice of dot-like spacers at an interval of 5 times / sec with a load of 50 gf from the transparent conductive film side. The time until the voltage reached 5 V was measured as the voltage loss time, starting from when the pen started to move away from the transparent conductive film and the voltage decreased from 6 V. For example, Figure 5 is a conceptual diagram showing the relationship between the voltage and the time in one embodiment of the present application, the horizontal axis 13 is the time axis, and the vertical axis 14 shows the voltage. The time of the voltage loss time 15 was measured.

[0087] The above transparent conductive film preferably has an ON resistance of 10 kΩ or less (characteristic 3) determined by the test method 6. The smaller the ON resistance, the more the pen slide durability can be improved. The ON resistance is preferably 8 kΩ or less, more preferably 5 kΩ or less, still more preferably 3 kΩ or less, and particularly preferably 1.0 kΩ or less. Note that the ON resistance can be, for example, 0.1 kΩ or more, 2 kΩ or more, or 4 kΩ or more. That is, the ON resistance is preferably 0.1 to 10 kΩ, more preferably 0.1 to 8 kΩ, still more preferably 0.1 to 5 kΩ, yet more preferably 0.1 to 3 kΩ, and particularly preferably 0.1 to 1 kΩ. In addition, it can be 2 to 10 kΩ, 2 to 8 kΩ, 2 to 5 kΩ, 2 to 3 kΩ, 4 to 10 kΩ, 4 to 8 kΩ, or 4 to 5 kΩ.

[0088] [Test method 6]

[0089] An evaluation panel was produced by overlapping a panel in which an indium-tin composite oxide conductive film (tin oxide content: 10 mass%) having a thickness of 20 nm was formed on one side of a glass substrate with a transparent conductive film with a diameter of 30 μm in such a manner that the conductive films faced each other with an epoxy microbead interposed therebetween. On the transparent conductive film side of the evaluation panel, a load of 2.5 N was applied while sliding (reciprocation number: 50,000 times, sliding distance: 30 mm, sliding speed: 180 mm / sec) with a pen having a hemispherical tip with a radius of 0.8 mm. After the sliding, the resistance when the sliding portion was pressed with a pen load of 0.8 N to be electrically connected (ON resistance) was measured.

[0090] The film stiffness (BR) of the above-described transparent conductive film, which is obtained by Test Method 3, is preferably 0.38 N-cm or more and 0.90 N-cm or less. By making the film stiffness (BR) be a prescribed value or more, it is possible to make the input start load be a prescribed value or more. In addition, by making the film stiffness (BR) be a prescribed value or less, it is possible to make the ON resistance be a prescribed value or less. Note that reducing the film stiffness (BR) is also useful for reducing the input start load. The film stiffness (BR) is more preferably 0.42 N-cm or more, and further preferably 0.46 N-cm or more. In addition, it is more preferably 0.80 N-cm or less, further preferably 0.70 N-cm or less, and particularly preferably 0.60 N-cm or less. That is, the film stiffness (BR) is more preferably 0.42 to 0.80 N-cm, further preferably 0.42 to 0.70 N-cm, and particularly preferably 0.46 to 0.60 N-cm.

[0091] [TEST METHOD 3]

[0092] A 20 mm x 250 mm transparent conductive film test piece was placed on a water table with the transparent conductive film facing upward, and the test piece was made to protrude from the end of the table by a length of 230 mm, and the stiffness (BR) was determined based on the following formula. Note that if the transparent conductive film is made to face downward, the value of the stiffness changes, so attention is required.

[0093] Stiffness (BR (N-cm)) = g x a x b x L 4 / (8 x δ x 10 11 )

[0094] (In the formula, g is 9.81 (acceleration due to gravity; m / s 2 ), a is 20 (length of the short side of the test piece; mm), b represents the specific gravity of the test piece (g / cm 3 ), L is 230 (length of the long side of the test piece exposed outside the water table; mm), and δ represents the difference between the height of the front end of the test piece and the height of the table (cm))

[0095] The average value (AVSp) of the maximum peak height Sp of the conductive surface of the above transparent conductive film, which is obtained by Test Method 4, preferably satisfies the following equation (2-1). The input start load is dominated by the two parameters of the film stiffness (BR) and the average maximum peak height (AVSp), and by making the average maximum peak height (AVSp) be a prescribed value or more, which is obtained from the film stiffness (BR), it is possible to make the input start load be a prescribed value or less. In addition, by making the average maximum peak height (AVSp) be a prescribed value or less, it is possible to make the input start load be a prescribed value or more, and in addition, it is sometimes possible to adjust the voltage loss time to a more preferable range.

[0096] 4.7 x BR - 3.6 ≤ AVSp < 4.7 x BR - 1.8... Equation (2-1)

[0097] (In the equation, BR is the film stiffness (N-cm), and AVSp is the average maximum peak height (μm))

[0098] [TEST METHOD 4]

[0099] In the conductive surface of the transparent conductive film, 5 measurement points are determined at intervals of 1 cm in the MD direction, and 2 points are determined symmetrically in the TD direction at intervals of 1 cm from the center thereof, and the maximum peak height Sp based on the surface roughness is measured at each portion (according to ISO 25178), and the average value thereof is taken as the average maximum peak height (AVSp) (μm).

[0100] The relationship of the inequality on the left side of Equation (2-1) is more preferably 4.7 x BR - 3.5 ≤ AVSp, and further preferably 4.7 x BR - 3.4 ≤ AVSp. The relationship of the inequality on the right side of Equation (2-1) is more preferably AVSp < 4.7 x BR - 1.9, and further preferably AVSp < 4.7 x BR - 2.0. That is, more preferably 4.7 x BR - 3.5 ≤ AVSp < 4.7 x BR - 1.9, and further preferably 4.7 x BR - 3.4 ≤ AVSp < 4.7 x BR - 2.0.

[0101] The above transparent conductive film preferably has the above average maximum peak height (AVSp) satisfy the following equation (2-2). If the average maximum peak height (AVSp) is a prescribed value or more, it is possible to roll the transparent conductive film into a roll without obstacles. The average maximum peak height (AVSp) is more preferably 0.010 (μm) or more, and further preferably 0.020 (μm) or more. In addition, by making the average maximum peak height (AVSp) be a prescribed value or less, it is possible to more suitably prevent accidental electrical contact.

[0102] 0.005 ≤ AVSp ≤ 12.000... Equation (2-2)

[0103] (In the equation, AVSp is the average maximum peak height (μm))

[0104] That is, the AVSp is more preferably 0.010 to 12.000 μm, and further preferably 0.020 to 12.000 μm.

[0105] The contact area ratio (CA) of the above-described transparent conductive film, which is obtained by Test Method 5, preferably satisfies the following equation (2-3). By setting the contact area ratio (CA) to be equal to or more than a prescribed value, it is possible to set the voltage loss time to be equal to or less than a prescribed value. The reason for this is believed to be that the greater the contact area ratio (CA), the higher the stability of the electrical contact between the conductive layers, and therefore, when a pen, finger, or the like is removed from the transparent conductive film of the resistive film type touch panel, it is possible to secure the time until the contact area at which the electrical contact becomes unstable. In addition, in equation (2-3), the reason why the greater the stiffness (BR), the greater the contact area ratio (CA) is believed to be that the greater the stiffness (BR), the greater the speed at which a pen, finger, or the like is removed from the transparent conductive film of the resistive film type touch panel, and therefore, a transparent conductive film having a large contact area ratio (CA) needs to be used.

[0106] CA ≥ 32.6 x BR + 17.2... Equation (2-3)

[0107] (Equation in which BR is the film stiffness (N-cm), and CA is the contact area ratio (%))

[0108] [TEST METHOD 5]

[0109] For the conductive surface of the transparent conductive film, the average height Rc (μm) based on line roughness, the maximum peak height Rp (μm), and the average length Rsm (μm) are measured, and the arithmetic average height Ra (μm) based on line roughness is measured at a portion that satisfies at least one of equation (X1) and equation (X2) and equation (X3). Note that the average height Rc (μm), the maximum peak height Rp (μm), the average length Rsm (μm), and the arithmetic average height Ra (μm) are determined using a three-dimensional surface shape measuring device, VertScan (Ryoka Systems Co., Ltd., R5500H-M100 (measurement conditions: wave mode, measurement wavelength 560 nm, objective lens 50x)). The determination of the maximum peak height Rp (μm), the average length Rsm (μm), and the arithmetic average height Ra (μm) is in accordance with the provisions of JIS B 0601-2001. The measurement length of the arithmetic average height Ra (μm) is set to be equal to or more than 100 μm and equal to or less than 200 μm.

[0110] Rp - Rc - Ra ≤ 0.20... Equation (X1)

[0111] (Rp - Rc) / Ra ≤ 5.0... Equation (X2)

[0112] Rsm ≤ 30... Equation (X3)

[0113] The objective lens of the three-dimensional surface shape measuring device VertScan described above was changed to 10 times, and particle analysis based on the measuring device was used to perform slicing in the planar direction at a height of "arithmetic average height Ra (pm) - 15 x 10 -3 (μm) - average height Rc (μm)", and the sum of the cross-sectional areas was calculated. The value obtained by multiplying the value obtained by dividing the sum of the cross-sectional areas by the area of the measuring field by 100 was taken as the contact area ratio (CA) (%).

[0114] In the above Test Method 5, "arithmetic average height Ra (pm) - 15 x 10 -3 (μm)" is based on the following reasons. Most of the transparent conductive film in contact with the transparent conductive glass is a protrusion of the average height of the transparent conductive film. Since it is difficult to accurately calculate the contact area with the protrusion of the average height, as an alternative index, the cross-sectional area of the transparent conductive film side of the transparent conductive film at a height slightly smaller than the height of the average protrusion (= a height of 15 x 10 -3 (μm) lower than the average height of the transparent conductive film) was used. Here, when the arithmetic average roughness Ra of JIS B 0601-2001 is used as the height of the average protrusion of the transparent conductive film, the arithmetic average roughness Ra becomes larger than the actual average protrusion height of the transparent conductive film due to the influence of the coarse protrusions that are few in number but have a very high height on the transparent conductive film side, and thus is not preferable. Therefore, in order to eliminate the influence of the coarse protrusions, the arithmetic average height Ra (pm) is measured at a site that satisfies at least one of Formula (X1) and Formula (X2) and Formula (X3).

[0115] The relationship of CA to BR represented by Formula (2-3) is more preferably CA > 32.6 x BR + 17.5, and further more preferably CA > 32.6 x BR + 18.0.

[0116] The maximum value MXSp of the maximum peak height Sp of the above transparent conductive film is preferably more than 1.0 times and 1.4 times or less (more preferably more than 1.0 times and 1.40 times or less) of the above average maximum peak height AVSp, as calculated by the above Test Method 4. By setting the maximum value MXSp to be a predetermined value or less, the in-plane distribution of the high protrusions of the transparent conductive film becomes uniform, and input operations of the touch panel can be performed with the same input start load at any site, and thus is preferable. More preferably, it is 1.3 times or less, and further more preferably, it is 1.2 times or less.

[0117] The minimum value MNSp of the maximum peak height Sp of the above-described transparent conductive film, which is obtained by the above-described test method 4, is preferably 0.6 times or more and 1.0 times or less (more preferably 0.60 times or more and 1.0 times or less) of the above-described average maximum peak height AVSp. By setting the minimum value MNSp to be the prescribed value or more, the in-plane distribution of the high protrusions of the transparent conductive film becomes uniform, and the input start load can be started at the same input at any site of the touch panel, and thus it is preferable. More preferably, it is 0.7 times or more, and further preferably, it is 0.8 times or more.

[0118] Further, by setting both the maximum value MXSp and the minimum value MNSp to be within the prescribed range, the deviation of the input start load can be made to be less than ±5% of the average value. Also, it is possible to prevent the input start load from deviating between products.

[0119] The total light transmittance of the above-described transparent conductive film is, for example, 70% or more and 95% or less, preferably 80% or more and 95% or less, and more preferably 85% or more and 90% or less.

[0120] 2. Transparent conductive film

[0121] The transparent conductive film of the transparent conductive film contains indium-tin composite oxide. The tin oxide concentration contained in the transparent conductive film of the transparent conductive film is preferably 0.5% by mass or more and 40% by mass or less. If the tin oxide concentration is 0.5% by mass or more, the surface resistance of the transparent conductive film reaches a practical level, and thus it is preferable. Further, by making the tin oxide concentration 40% by mass or less, it is possible to make the tin oxide concentration contained in the transparent conductive film of the transparent conductive film close to the tin oxide concentration contained in the transparent conductive glass substrate for a touch panel. The closer the tin oxide concentrations of the transparent conductive film and the transparent conductive film of the glass substrate, the more easily the two transparent conductive films come into electrical contact, and the adaptive input strength and input stability become better. The tin oxide concentration of the transparent conductive film is more preferably 25% by mass or less, further preferably 20% by mass or less, particularly preferably 18% by mass or less, more preferably 1% by mass or more, and further preferably 2% by mass or more. That is, the tin oxide concentration is more preferably 1 to 25% by mass, further preferably 1 to 20% by mass, and particularly preferably 2 to 18% by mass.

[0122] Note that the tin oxide concentration contained in the transparent conductive glass substrate for a touch panel is generally 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.

[0123] The crystallinity of the transparent conductive film can be any one of 0% or more and 100% or less, preferably 10% or more and 100% or less, more preferably 50% or more and 100% or less. The higher the crystallinity, the more excellent the pen sliding properties.

[0124] The surface resistance of the transparent conductive film is, for example, 50 Ω / D or more and 900 Ω / D or less, preferably 50 Ω / D or more and 700 Ω / D or less, more preferably 70 Ω / D or more and 500 Ω / D or less.

[0125] The thickness of the transparent conductive film is preferably 10 nm or more and 100 nm or less. 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 cured resin layer described later, the film quality of the transparent conductive film is stable, the surface resistance value is stable, and it is easy to be in the preferable range. In addition, it is also effective to reduce the ON resistance determined by Test Method 6. More preferably, the thickness of the transparent conductive film is 13 nm or more, and more preferably 16 nm or more. In addition, if the thickness of the transparent conductive film is 100 nm or less, the crystal grain diameter and the crystallinity of the transparent conductive film become moderate, and the total light transmittance becomes a practical level, and thus it is preferable. More preferably, it is 50 nm or less, further preferably 30 nm or less, and particularly preferably 25 nm or less. That is, the thickness of the transparent conductive film is more preferably 13 to 50 nm, further preferably 16 to 30 nm, and particularly preferably 16 to 25 nm.

[0126] In the adhesion test according to JIS K5600-5-6:1999 on the surface of the transparent conductive film, the residual area rate of the transparent conductive film is preferably 95% or more, further preferably 99% or more, and particularly preferably 99.5% or more. By making the residual area rate of the transparent conductive film in the adhesion test be in the above range, the layer such as the transparent plastic film substrate, the cured resin layer described later, and the like in contact with the transparent conductive film is firmly adhered to the transparent conductive film for the transparent conductive film, and even if continuous input is made to the touch panel by a pen, cracks, peeling, abrasion, and the like can be suppressed for the transparent conductive film, and in addition, even if a stronger force than that assumed for usual use is applied, cracks, peeling, and the like can be suppressed for the transparent conductive film, and thus it is preferable.

[0127] The method of forming the above transparent conductive film is not particularly limited, and for example, a method of forming a transparent conductive film of an indium-tin composite oxide on at least one surface of a transparent plastic film substrate 7 (hereinafter, referred to as a treated film) on which a cured resin layer 6 can be formed on the surface is preferable. In order to manufacture the transparent conductive film at a high productivity, it is preferable to use a so-called roll-type sputtering device that supplies the treated film from a film roll, and winds the film into the shape of a film roll after film formation.

[0128] Figure 6is a device schematic diagram showing one example of a film deposition section in a roll-type sputtering device. In this example, a processed film 1 fed out from a film roll travels while partially contacting the surface of a center roll 2. A sputtering target 4 of indium-tin is provided inside a chimney 3 having an opening portion toward the contact portion of the processed film 1 and the center roll 2, and a thin film of an indium-tin composite oxide is deposited on the surface of the processed film 1 traveling on the center roll 2. Note that the center roll 2 can be temperature-controlled by a temperature controller not shown.

[0129] As the target, a sintered target of an indium-tin composite oxide is preferably used. In order to improve the production efficiency, a plurality of sintered targets of an indium-tin composite oxide can be provided with respect to the flow direction of the film.

[0130] In the formation of the film deposition atmosphere, oxygen, an inactive gas (argon or the like), or the like is preferably caused to flow using a mass flow controller as necessary. By adding oxygen, the surface resistance and the total light transmittance of the transparent conductive film can be more appropriately adjusted. The flow rate ratio (volume ratio) of oxygen to the inactive gas (oxygen / inactive 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, further preferably 0.05 or less. That is, the flow rate ratio (volume ratio) of oxygen to the inactive gas (oxygen / inactive gas) is, for example, 0.005 to 0.15, preferably 0.010 to 0.1, more preferably 0.020 to 0.07, further preferably 0.020 to 0.05.

[0131] In addition, in the film deposition atmosphere, a gas containing a hydrogen atom (hydrogen, ammonia, hydrogen + argon mixed gas, or the like, and there is no particular limitation as long as it is a gas containing a hydrogen atom. Among them, water is excluded.) can be caused to flow using a mass flow controller as necessary.

[0132] The central value (value intermediate between the maximum value and the minimum value) of the ratio of the water partial pressure to the inactive gas partial pressure (water partial pressure / inactive gas partial pressure) in the film deposition atmosphere is, for example, 7.00 x 10 -3 Hereinafter, the central value is preferably 5.00 x 10 -3 Hereinafter, the central value is more preferably 3.00 x 10 -3The less the water in the film forming atmosphere, the more suitable the film quality of the transparent conductive film, the more easily the surface resistance value becomes a preferred value, and the reliability of crystallization improves. However, the amount of moisture is also controlled based on the limit vacuum, but measuring the amount of moisture (moisture pressure) at the time of film formation is preferable for the following two reasons. First, if film formation is performed on a plastic film by sputtering, the film is heated, and moisture is released from the film. In the limit vacuum, the effect of this released amount of moisture is not reflected. Second, the effect of the moisture at the center of the roll from which the film is rolled out at the time of film formation is not reflected in the limit vacuum. If the film roll is kept in a vacuum tank, the moisture of the outer layer portion of the roll easily escapes, but the moisture of the inner layer portion of the roll is difficult to escape. When the limit vacuum is measured, the film travel stops, but the film travels at the time of film formation, and the inner layer portion of the film roll containing more moisture is rolled out, so the amount of moisture in the film forming atmosphere increases compared to the amount of moisture at the time of measuring the limit vacuum.

[0133] For the film roll used to form the transparent conductive film, the height difference between the most convex position and the most concave position at the roll end surface is preferably 10 mm or less, more preferably 8 mm or less, and further preferably 4 mm or less. If it is 10 mm or less, the water and organic components are not easily released from the film end surface at the time of feeding the film roll into the sputtering device, so the film quality of the transparent conductive film becomes good.

[0134] Before forming the transparent conductive film, it is preferable to pass the treated film through a bombardment process. The bombardment process refers to applying a voltage to perform discharge to generate plasma in a state of flowing only a non-reactive gas such as argon or a mixed gas of a reactive gas such as oxygen and a non-reactive gas. Specifically, it is preferable to bombard the film by RF sputtering using a SUS target or the like. Since the film is exposed to plasma by the bombardment process, water and organic components are released from the film, and the amount of water and organic components released from the film is reduced at the time of forming the transparent conductive film, so the film quality of the transparent conductive film becomes good. In addition, by the bombardment process, the layer with which the transparent conductive film comes into contact is activated, so the adhesion of the transparent conductive film improves, and the pen slide durability further improves.

[0135] The above-mentioned treated film 1 is desirably previously attached with a protective film having a low water absorption rate on the opposite surface of the surface on which the transparent conductive film is formed. By attaching the protective film, water and the like are not easily released from the treated film 1, so the film quality of the transparent conductive film becomes good. As the base material of the above-mentioned protective film, for example, polyethylene, polypropylene, cyclic olefin, and the like can be cited.

[0136] At the time of film formation, the treated film 1 is cooled to, for example, 0°C or lower, and preferably to -5°C or lower. By previously cooling the treated film 1, the release of impurities such as water, organic gas, and the like from the film can be suppressed, and the film quality of the transparent conductive film can be made suitable. The film temperature in the film formation can be replaced with the set temperature of a temperature controller that adjusts the temperature of the center roll with which the film comes into contact.

[0137] The sputtering apparatus preferably has an exhaust device such as a rotary pump, a turbo molecular pump, or a cryopump. By the exhaust device, the amount of moisture in the film formation atmosphere can be controlled.

[0138] Ideally, after the transparent conductive film of indium-tin composite oxide is formed on the film to be processed and laminated, a heat treatment is performed in an atmosphere containing oxygen at 80°C or higher and 200°C or lower for 0.1 hours or more and 12 hours or less. By being set to 80°C or higher, the crystallinity of the transparent conductive film can be improved, and the pen slide durability can be further improved. By being set to 200°C or lower, the planarity of the transparent plastic film can be ensured.

[0139] 3. Transparent plastic film substrate

[0140] The transparent plastic film substrate used in the present application refers to a film obtained by melt-extruding or solution-extruding an organic polymer into a film shape and, as needed, performing stretching, cooling, and heat fixation in the length direction and / or the width direction. As the organic polymer, polyethylene, polypropylene, and the like polyolefins; polyethylene terephthalate, polyethylene 2,6-naphthalate, polytrimethylene terephthalate, polybutylene terephthalate, and the like polyesters; nylon 6, nylon 4, nylon 66, nylon 12, and the like polyamides; polyimide, polyamide-imide, polyether sulfone, polyether ether ketone, polycarbonate, polyarylate, cellulose propionate, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyetherimide, polyphenylene sulfide, polyphenylene ether, polystyrene, syndiotactic polystyrene, norbornene-based polymers, and the like can be given.

[0141] Among these organic polymers, polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene 2,6-naphthalate, syndiotactic polystyrene, norbornene-based polymers, polycarbonate, polyarylate, and the like are preferable. In addition, these organic polymers can have a small amount of monomers of other organic polymers copolymerized or be blended with other organic polymers.

[0142] Within a range not impairing the object of the present application, the transparent plastic film substrate can be subjected to surface activation treatment such as corona discharge treatment, glow discharge treatment, flame treatment, ultraviolet irradiation treatment, electron beam irradiation treatment, ozone treatment, and the like.

[0143] The thickness of the transparent plastic film substrate is preferably in the range of 125 μm or more and 280 μm or less, and more preferably in the range of 150 μm or more and 250 μm or less. The thicker the transparent plastic film substrate, the more easily the stiffness (BR) of the film becomes high, and the more easily the average maximum peak height (AVSp) satisfies the right side of the formula (2-1). In addition, if the thickness of the transparent plastic film substrate is 125 μm or more, the mechanical strength is maintained, and in particular when used for a touch panel, the false input resistance becomes good, and in addition, the deformation to a pen input when used for a touch panel is small, and the pen slide durability is excellent, and thus is preferred. On the other hand, if the thickness is 280 μm or less, when used for a touch panel, the adaptive input strength and excellent input stability can be maintained, and thus is preferred.

[0144] 4. Cured resin layer

[0145] The cured resin layer is formed, for example, between the transparent plastic film substrate and the transparent conductive film, and becomes a base layer of the transparent conductive film. In addition, since the monomer and oligomer generated from the transparent plastic film substrate can be prevented from being deposited on the transparent conductive film, the comfortable input property of the touch panel is not hindered, and thus is preferred. In addition, the transparent conductive film and the cured resin layer can be strongly adhered by an easy-adhesion layer or the like, and the force applied to the transparent conductive film can be dispersed, and thus, in the pen slide durability test, cracks, peeling, abrasion, and the like of the transparent conductive film can be suppressed, and thus is preferred.

[0146] The resin of the cured resin layer is not particularly limited as long as it is a resin cured by energy application such as heating, ultraviolet irradiation, electron beam irradiation, a curing agent, and the like, and for example, a silicone-based resin, an acrylic-based resin, a methacrylic-based resin, an epoxy-based resin, a melamine-based resin, a polyester-based resin, a urethane-based resin, and the like can be given, and they can be one kind or two or more kinds in combination. From the viewpoint of productivity, a ultraviolet-curable resin is preferred as a main component.

[0147] As the ultraviolet-curable resin, for example, a multifunctional acrylate resin such as an acrylate or a methacrylate ester of a polyol; a multifunctional urethane acrylate resin synthesized from a diisocyanate, a polyol, and a hydroxyalkyl ester of acrylic acid or methacrylic acid, and the like can be given. If necessary, a monofunctional monomer such as a vinylpyrrolidone, a methyl methacrylate, a styrene, and the like can be added to these multifunctional resins to perform copolymerization.

[0148] The curable resin layer preferably contains a curing reaction initiator at least before curing. The curing reaction initiator can be selected depending on the kind of curing of the curable resin, and examples include a thermal polymerization initiator, a photopolymerization initiator such as a radical polymerization initiator, a curing agent, and the like, with a photopolymerization initiator being preferred. The amount of the curing reaction initiator is, for example, 1 parts by mass or more and 5 parts by mass or less, relative to 100 parts by mass of the curable resin.

[0149] As the photopolymerization initiator, a publicly known compound that generates radicals by absorbing ultraviolet rays can be used without particular limitation, and examples include various benzoin compounds, phenyl ketone compounds, benzophenone compounds, and the like.

[0150] The curable resin layer preferably contains particles. By the particles, a concave-convex structure can be formed on the surface of the curable resin layer. Therefore, if the particles are contained, the contact area ratio CA substantially decreases from 100%, and on the other hand, the control of the average maximum peak height AVSp becomes easy. In addition, by increasing the amount of the particles, the stiffness BR sometimes decreases, and the stiffness BR can also be adjusted by the amount of the particles. Furthermore, by the particles, various characteristics such as pen slide durability, resistance to Newton's rings, coiling property of the film, and the like can be more effectively exhibited. Note that in the case where the amount of addition of relatively large particles (for example, particles A described later) is small and the amount of addition of relatively small particles (for example, particles B described later, which are used in combination with the particles A) is large, there is a tendency that the contact area ratio CA and the average maximum peak height AVSp become larger than in the case where the same size particles are added.

[0151] As the above-mentioned particles, inorganic particles, organic particles, and the like can be given, with inorganic particles being preferred. As the inorganic particles, silica particles and the like can be given. As the organic particles, particles containing a polyester resin, a polyolefin resin, a polystyrene resin, a polyamide resin, and the like can be given. The particles can be one kind or two or more kinds.

[0152] The number average particle diameter of the above-mentioned particles is, for example, 0.01 μm or more and 10 μm or less, preferably 0.03 μm or more and 5 μm or less, more preferably 0.05 μm or more and 3 μm or less, and particularly preferably 0.05 μm or more and 1.8 μm or less. The larger the average particle diameter, the larger the average maximum peak height AVSp of the transparent conductive layer can be made. Note that as for the average maximum peak height, in addition to the increase by the increase in the average particle diameter, the increase can also be made by increasing the resin concentration (solid content concentration) in the coating liquid of the curable resin described later, reducing the thickness of the curable resin layer, and the like.

[0153] In addition, the standard deviation of the above-mentioned particle diameter is, for example, 20% or less of the average particle diameter, preferably 10% or less of the average particle diameter, and more preferably 5% or less of the average particle diameter. The smaller the standard deviation of the particle diameter, the larger the contact area ratio CA of the transparent conductive film can be made.

[0154] In one embodiment, it is preferable to use one kind of particles B having a number average particle diameter of 0.01 μm or more and less than 1.0 μm, and in another embodiment, it is preferable to use in combination particles A having a number average particle diameter of 0.4 μm or more and 1.8 μm or less and a larger number average particle diameter than particles B, and particles B having a number average particle diameter of 0.01 μm or more and less than 1.0 μm. The average particle diameter of particles B is preferably 0.05 μm or more. If the average maximum peak height AVSp becomes large (for example, 0.6 μm or more), the contact area ratio CA sometimes becomes too small, and if both particles A and particles B are used, the contact area ratio can be made appropriate. Note that if the average maximum peak height AVSp reaches the right side of formula (2-1) (4.7 x BR -1.8) or more, even if both particles A and particles B are used, the contact area ratio CA becomes too small, and thus it is necessary to make the average maximum peak height AVSp smaller than the right side of formula (2-1) in advance.

[0155] In the case where one kind of particles B is contained, the amount of particles B in the curable resin layer is, for example, 0.1% by mass or more and 25% by mass or less, and preferably 0.5% by mass or more and 18% by mass or less, with respect to 100% by mass of the solid content of the cured resin layer.

[0156] In the case where both particles A and particles B are contained, the amount of particles A in the curable resin layer is, for example, 0.1% by mass or more and 5% by mass or less, with respect to 100% by mass of the solid content of the cured resin layer. The amount of particles B in the curable resin layer is preferably more than the amount of particles A, and is, for example, more than 5% by mass and 30% by mass or less, and preferably 6% by mass or more and 15% by mass or less, with respect to 100% by mass of the solid content of the cured resin layer.

[0157] By adjusting the size and amount of the particles as described above, it is possible to make the average maximum peak height AVSp of the transparent conductive layer satisfy formula (2-1), and the contact area ratio CA does not become too small. In addition, it is also possible to adjust the stiffness BR of the film. Therefore, it is possible to control the input start load in an appropriate range, shorten the voltage loss time, and achieve an adaptive input intensity and input stability.

[0158] The thickness of the curable resin layer is preferably in the range of 0.1 μm or more and 15 μm or less. It is more preferably in the range of 0.5 μm or more and 10 μm or less, and particularly preferably in the range of 1 μm or more and 8 μm or less. In the case where the thickness of the curable resin layer is 0.1 μm or more, a sufficient protrusion is formed, which is preferable. On the other hand, if it is 15 μm or less, the productivity is good, which is preferable. In addition, if the curable resin layer is thick, there is a tendency that the stiffness BR of the transparent conductive film increases.

[0159] The curable resin layer can contain a resin (hereinafter, sometimes referred to as a non-compatible resin) that is not compatible with the curable resin. By dispersing the non-compatible resin in the curable resin layer, it is possible to form unevenness on the surface of the curable resin layer, and it is possible to increase the surface roughness of the wide area. As the non-compatible resin, a polyester resin, a polyolefin resin, a polystyrene resin, a polyamide resin, and the like can be exemplified.

[0160] The curable resin layer is formed by coating the curable resin in a liquid state before curing on the laminated object (transparent plastic film substrate, easy adhesive layer, or the like) and curing. The coating material can contain, in addition to the curable resin described above, a curing reaction initiator (a thermal polymerization initiator, a photopolymerization initiator such as a radical polymerization initiator, a curing agent, or the like. A photopolymerization initiator is preferred), a particle, a resin that is not compatible with the curable resin, a solvent, and the like. In addition, in this coating liquid, other publicly known additives such as a silicone-based leveling agent or the like can be added as needed. The solvent used is not particularly limited, and for example, alcohol-based solvents such as ethanol, isopropanol, or the like, ester-based solvents such as ethyl acetate, butyl acetate, or the like, ether-based solvents such as dibutyl ether, ethylene glycol monoethyl ether, or the like, ketone-based solvents such as methyl isobutyl ketone, cyclohexanone, or the like, aromatic hydrocarbon-based solvents such as toluene, xylene, solvent naphtha, or the like, and the like can be used alone or in combination.

[0161] The concentration of the curable resin in the coating liquid (referred to as the solid content concentration) can be appropriately selected in consideration of the viscosity or the like corresponding to the coating method. The solid content concentration is, for example, 35% by mass or more and 58% by mass or less, and is preferably 42% by mass or more and 55% by mass or less. If the solid content concentration is high, and the thickness of the curable resin layer is thin (for example, 4.0 μm or less), there is a tendency for the average maximum peak height of the curable resin layer to be high due to the relationship of formula (2-1), or for the contact area ratio CA to be small. Note that in the case where the solid content concentration exceeds 58% by mass (for example, to the extent of exceeding 58% by mass and being 65% by mass or less), even if the thickness of the curable resin layer is 4.0 μm or less, if the particle diameter of the particle A is 0.80 μm or less and the amount of the particle A is 4% by mass or less with respect to 100% by mass of the solid content of the curable resin layer in the case where the particle A and the particle B are used in combination, it is also easy to bring the average maximum peak height and the contact area ratio CA from the viewpoint of formula (2-1) to the appropriate range.

[0162] The method of applying the above coating liquid to the laminated object is not particularly limited, and for example, a known method such as a bar coating method, a gravure coating method, a reverse coating method, or the like can be used. The applied coating liquid is evaporated to remove the solvent in the following drying step. In the case where the non-compatible resin (polyester resin or the like) is dissolved in the coating liquid, the non-compatible resin becomes particles and is precipitated in the ultraviolet-curable resin in this drying step. After drying the coating film, appropriate processing (for example, ultraviolet irradiation) corresponding to the type of curing is performed, whereby a curable resin layer can be formed.

[0163] For the coated surface of the laminated object, before the coating of the coating liquid, adhesion improving processing of the curable resin layer can be performed as necessary. As the adhesion improving processing, a discharge processing method of irradiating glow or corona discharge for increasing carbonyl, carboxyl, hydroxyl groups, a chemical agent processing method of processing with an acid or a base for increasing polar groups such as amino groups, hydroxyl groups, carbonyl groups, or the like can be cited.

[0164] As described above, in order to set the average maximum peak height AVSp to a prescribed range, and set the contact area ratio CA to a prescribed range, various factors need to be adjusted, the details of which are as described above, but if the details are omitted and the outline is described, the adjustment can be performed by utilizing the following relationships. That is, basically, if the particle diameter is large, and the solid content concentration is high, or the thickness of the resin layer is thin, there is a tendency for the absolute value of the average maximum peak height AVSp to become large. The average maximum peak height AVSp satisfying the formula (2-1) varies depending on the stiffness BP, and the smaller the stiffness BP, the smaller the average maximum peak height AVSp. In addition, basically, if the average maximum peak height AVSp becomes high, the contact area ratio CA becomes small. However, as the average particle diameter added in the resin layer, if two kinds of sizes are used, and the amount of addition of the large particles is reduced, the average maximum peak height AVSp becomes high, and the contact area ratio CA becomes high. In the case where two kinds of sizes of particles are used, the smaller the amount of addition of the large particles, the greater the influence of the average particle diameter of the small particles on the contact area ratio CA.

[0165] 5. Functional Layer

[0166] The functional layer, in addition to being formed on the opposite surface of the transparent plastic film substrate, is preferably the same as the above-described curable resin layer, and in addition to the description of the size and amount of the particles, the description of the above-described curable resin layer is entirely applicable to the functional layer. If the functional layer is laminated on the transparent plastic film substrate, it is possible to prevent the monomer, oligomer from being precipitated from the transparent plastic film substrate, and it is possible to suppress the reduction in visibility of the transparent conductive film. In addition, it is possible to adjust the stiffness BR of the transparent conductive film. In addition, by having the functional layer on the transparent plastic film substrate, it is less likely to cause scratches due to input with a pen or the like, and thus is preferable.

[0167] In the case where the particles (particles C) are incorporated in the functional layer, the number average particle diameter of the particles 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.

[0168] The particles C are preferably 0.1 parts by mass or more and 60 parts by mass or less, more preferably 0.3 parts by mass or more and 40 parts by mass or less, and further preferably 0.5 parts by mass or more and 30 parts by mass or less, with respect to 100 parts by mass of the curable resin in the functional layer. The stiffness BR of the transparent conductive film can be adjusted using the amount of the particles C. In addition, the particles C can form surface protrusions in the functional layer, and the film windability can also be maintained.

[0169] 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, further preferably 99% or more, and particularly preferably 99.5% or more. By making the residual area ratio of the functional layer within the above range in the adhesion test, the transparent plastic film substrate and the functional layer are firmly bonded in the transparent conductive film, and even if continuous input is performed on the touch panel using a pen, appearance defects such as cracking, peeling, and abrasion of the functional layer can be suppressed, and even if a stronger force than that normally used is applied, cracking and peeling of the functional layer can be suppressed, and thus the transparent conductive film is preferably used.

[0170] In the case where the transparent conductive film has the functional layer and the cured resin layer, the thicknesses of the functional layer and the cured resin layer are preferably the same, and in addition, the absolute value of the difference between the thicknesses of the functional layer and the cured resin layer preferably has the following relationship.

[0171] 0.1 μm ≤ | thickness of the cured resin layer - thickness of the functional layer | ≤ 3 μm

[0172] By providing a difference in thickness between the functional layer and the cured resin layer, the stiffness BR of the transparent conductive film can sometimes be adjusted. In addition, various characteristics such as pen slide durability can be more effectively exhibited. Furthermore, the adaptive input strength can be further improved.

[0173] In addition, the particle mass per unit volume of the cured resin layer and the particle mass per unit volume of the functional layer are preferably different.

[0174] 6. Easy-adhesion layer

[0175] The easy-adhesion layer is preferably formed of a composition containing a urethane resin, a crosslinking agent, and a polyester resin. As the crosslinking agent, a blocked isocyanate is preferred, a blocked isocyanate having 3 or more functions is further preferred, and a blocked isocyanate having 4 or more functions is particularly preferred. The thickness of the easy-adhesion layer is preferably 0.001 μm or more and 2.00 μm or less.

[0176] This application claims the benefit of priority of Japanese Patent Application No. 2021-103501 filed on June 22, 2021. The specification of Japanese Patent Application No. 2021-103501 filed on June 22, 2021 is hereby incorporated by reference into the present application in its entirety.

[0177] Embodiments

[0178] Hereinafter, the present application will be further explained in detail by way of examples, but the present application is not limited to any of these examples. Note that the various measurement evaluations in the examples were performed by the following methods.

[0179] 1. Measurement Evaluation

[0180] (1) Average particle diameter of the silicon dioxide particles

[0181] The particles of the cross section of the transparent conductive film were observed using a scanning electron microscope (KEYENCE Corporation, VE-8800), and 50 particles were randomly selected, and the particle diameter of each was observed. Next, for the 50 particles observed, the particle diameters were divided in intervals of 0.020 pm, and the total number of particles contained in each interval was calculated, and a histogram of the particle diameter with the vertical axis as the number of particles and the horizontal axis as the 0.020 pm interval scale was prepared. Among the particles reaching the particle diameter that was within ±30% of the absolute value of the center value of the particle diameter interval from the maximum value of the peak of the normal distribution shape from the histogram, the average number of observed particle diameters was taken as the average particle diameter. For example, in the case where there were 2 peaks of the normal distribution shape in the histogram, it was indicated that 2 kinds of particles were added, and the average particle diameters of the 2 kinds of particles were calculated by the same method as described above.

[0182] (2) Thickness of the curable resin layer, thickness of the functional layer

[0183] The thickness of the curable resin layer was measured by the following method: the cross section of the transparent conductive film was observed using a scanning electron microscope (KEYENCE Corporation, VE-8800), and 5 points were observed, and the average value thereof was taken as the thickness. The same method was used for the thickness of the functional layer.

[0184] (3) Content of tin oxide contained in the transparent conductive film

[0185] The sample was cut and placed in a (about 15 cm 2) In a quartz-made conical flask, 20 ml of 6 mol / l hydrochloric acid was added, and the membrane was sealed so that no acid would evaporate. The transparent conductive film was dissolved by leaving it at room temperature for 9 days while shaking it from time to time. The remaining film was taken out, and the hydrochloric acid in which the transparent conductive film was dissolved was used as a measurement solution. In, Sn in the dissolved solution were obtained by a standard curve method using an ICP emission analysis device (manufacturer's name: Rigaku, device model: CIROS-120EOP). The determination wavelength of each element was selected so as to be a wavelength having high sensitivity without interference. In addition, a standard solution was used by diluting commercially available standard solutions of In, Sn.

[0186] (4) Thickness of transparent conductive film

[0187] The film sample piece on which the transparent conductive film was laminated was cut into a size of 1 mm x 10 mm, and embedded in an epoxy resin for electron microscopy. This was fixed to a sample holder of an ultramicrotome, and a cross-sectional thin section parallel to the short side of the embedded sample piece was prepared. Next, using a transmission electron microscope (manufactured by JEOL, Ltd., JEM-2010), a part of the thin film of the section where no significant damage was observed was photographed at an accelerating voltage of 200 kV, in a bright field, at an observation magnification of 10,000 times, and the film thickness was obtained from the obtained photograph.

[0188] (5) Crystallinity of transparent conductive film

[0189] The film sample piece on which the transparent conductive film was laminated was cut into a size of 1 mm x 10 mm, and the conductive film surface was attached to the upper surface of a proper resin block with the conductive film surface facing outward. After trimming, an ultrathin section substantially parallel to the film surface was prepared by a technique of a general ultramicrotome. The section was observed using a transmission electron microscope (manufactured by JEOL, Ltd., JEM-2010), and a part of the conductive film surface where no significant damage was observed was photographed at an accelerating voltage of 200 kV, at a direct magnification of 40,000 times. As an evaluation of the crystallinity of the transparent conductive film, the proportion of the crystal grains observed under the transmission electron microscope, that is, the crystallinity was observed.

[0190] (6) Total light transmittance (%)

[0191] The total light transmittance was measured using NDH-2000 manufactured by Nippon Denshoku Industries Co., Ltd. in accordance with JIS-K7361-1:1997.

[0192] (7) Surface resistance

[0193] The measurement was performed by a 4-terminal method in accordance with JIS-K7194:1994. The measurement machine used was Lotesta AX MCP-T370 manufactured by Mitsubishi Chemical Analytech Co., Ltd.

[0194] (8) Adhesion test

[0195] This was performed in accordance with JIS K5600-5-6:1999. The results in the following table are expressed as the residual area ratio (%) of adhesiveness. The maximum value of the residual area ratio is 100%. The closer the residual area ratio of the adhesiveness test in the table is to 100%, the less the peeling area.

[0196] (9) Stiffness (BR) (Test Method 3)

[0197] A test piece of 20 mm x 250 mm was cut from the transparent conductive film, and the test piece was arranged on a water platform with a smooth surface with the transparent conductive film facing upward. Only a 20 mm x 20 mm portion of the test piece was placed on the water platform, and a 20 mm x 230 mm portion was horizontally projected from the end of the platform. Note that a weight was placed on the 20 mm x 20 mm portion of the test piece in such a manner that no gap was created between the test piece and the water platform, and the weight and size of the weight were selected. Next, the difference (δ) between the height of the water platform and the height of the leading end of the film was read using a ruler. The value was substituted into the following equation to calculate the stiffness.

[0198] Stiffness BR (N-cm) = g x a x b x L 4 / (8 x δ x 10 11 )

[0199] (In the equation, g is 9.81 (acceleration due to gravity; m / s 2 ), a is 20 (length of the short side of the test piece; mm), b represents the specific gravity of the test piece (g / cm 3 ), L is 230 (length of the long side of the test piece exposed outside the water platform; mm), and δ represents the difference (cm) between the height of the leading end of the test piece and the height of the platform)

[0200] The specific gravity b described above was measured by the following method.

[0201] The transparent conductive film was cut into a square of 5.0 cm on each side, and the total thickness of 10 points was measured using a micrometer with a 3-digit significant digit change unit to obtain the average value of the thickness (t: μm). The weight (w: g) of the sample cut into a square of 5.0 cm on each side was measured using an automatic dish balance with a 4-digit significant digit, and the specific gravity was calculated by the following equation. Note that the specific gravity was rounded to 2-digit significant digits.

[0202] Specific gravity b (g / cm 3 ) = w / (5.0 x 5.0 x t x 10 -4 )

[0203] (10) Maximum peak height (Sp), average maximum peak height AVSp (μm) (Test Method 4)

[0204] The maximum peak height (Sp) (ISO; surface roughness) of 5 points was measured from the conductive surface of the transparent conductive film, and the arithmetic average thereof was taken as the average maximum peak height (AVSp). As to the selection method of the 5 points, first, an arbitrary 1 point A was selected. Next, 1 point each was selected at 1 cm upstream and downstream of the film in the length (MD) direction with respect to A, for a total of 2 points. Next, 1 point each was selected at 1 cm left and right of the film in the width (TD) direction with respect to A, for a total of 2 points. The maximum peak height (Sp) (ISO; surface roughness) is specified by ISO 25178, and was calculated using a three-dimensional surface shape measuring device, VertScan (Ryoka Systems Co., Ltd., R5500H-M100 (measurement conditions: wave mode, measurement wavelength 560 nm, objective lens 10 times)). In addition, values less than 1 nm were rounded off.

[0205] (11) Maximum peak height upper side displacement rate (MXSp / AVSp), maximum peak height lower side displacement rate (MNSp / AVSp)

[0206] The ratio of the maximum value MXSp to the average value AVSp of the maximum peak height Sp calculated by the above Test Method 4 was taken as the maximum peak height upper side displacement rate (MXSp / AVSp).

[0207] In addition, the ratio of the minimum value MNSp to the average value AVSp of the maximum peak height Sp calculated by the above Test Method 4 was taken as the maximum peak height lower side displacement rate (MNSp / AVSp).

[0208] (12) Contact area rate CA (%), average height Rc (μm), maximum peak height Rp (μm), average length Rsm (μm), arithmetic average height Ra (μm) (Test Method 5)

[0209] 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. At 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. It should be noted that the average height Rc (μm), maximum peak height Rp (μm), average length Rsm (μm), and arithmetic mean height Ra (μm) are determined using a three-dimensional surface shape measuring device, VertScan (Ryoka Systems, R5500H-M100 (measurement conditions: wave mode, measurement wavelength 560nm, objective lens 50x)). It should be noted that the determination of the maximum peak height Rp (μm), average length Rsm (μm), and arithmetic mean height Ra (μm) follows the provisions of JIS B 0601-2001. The measurement length for the arithmetic mean height Ra (μm) is set to be above 100μm and below 200μm.

[0210] Rp-Rc-Ra≤0.20…Equation (X1)

[0211] (Rp-Rc) / Ra≤5.0…Equation (X2)

[0212] By changing the objective lens of the VertScan three-dimensional surface shape measuring device to 10x, and using particle analysis based on this measuring device, the arithmetic mean height Ra (μm) – 15 × 10⁻¹⁵ μm from the average surface was achieved. -3 The height of “(μm) – average height Rc(μm)” is sliced ​​along the plane, and the total cross-sectional area is calculated. The total cross-sectional area is divided by the area of ​​the measured field of view, and the result is multiplied by 100 to obtain the contact area ratio (CA) (%).

[0213] (13) Input the initial load measurement (Test Method 1)

[0214] like Figure 6 As shown, for the cured resin layer of the laminated film (the film to be treated) 1 on the center roller 2, a transparent conductive film is formed by sputtering from the target 4 inside the cover 3. The target 4 uses a sintered target of indium-tin composite oxide or a sintered target of indium oxide without tin oxide, at a speed of 3W / cm². 2 A transparent conductive film is formed by applying a high power density to the target and then using DC magnetron sputtering. The film thickness is controlled by changing the speed at which the film passes over the target.

[0215] An indium-tin composite oxide conductive film with a thickness of 20 nm (tin oxide content: 10% by mass) was formed on one side of a glass substrate (size: 232 mm × 151 mm) by sputtering. Specifically, a 1.1 mm thick glass substrate (size: 232 mm × 151 mm) was placed in a vacuum chamber, and the vacuum was evacuated to 1.5 × 10⁻⁶. -4 Pa. Next, 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. A sintering target of indium-tin composite oxide (tin oxide content: 10% by mass) was used at a flow rate of 3 W / cm. 2 A 20 nm thick indium-tin composite oxide conductive film (tin oxide content: 10% by mass) was formed on one side of a glass substrate using DC magnetron sputtering with an applied power density. The glass substrate was then heated in air at 230°C for 1 hour. On the surface of the conductive film formed on one side of the glass substrate, epoxy resin (manufactured by Toyobo Co., Ltd., product name: CR-102C-23) dots (60 μm x 60 μm x 5 μm) were spaced at 4 mm intervals to form a square grid (ITO glass substrate). Double-sided adhesive tape (105 μm thick, 6 mm wide) was then adhered to the transparent conductive film side, forming a 190 mm x 135 mm rectangle starting from any one of the four corners of the ITO glass substrate. A transparent conductive film (size: 220mm × 135mm) obtained in the examples or comparative examples is attached to a double-sided adhesive tape adhered to an ITO glass substrate, and the conductive films are stacked with each other facing each other. At this time, one short side of the transparent conductive film protrudes from the ITO glass substrate (evaluation panel).

[0216] The ITO glass substrate of the obtained evaluation panel was connected to the transparent conductive film using a tester. A load was applied from the transparent conductive film side using a polyacetal pen (manufactured by Toray Plastics Precision Co., Ltd., trade name: TPS (registered trademark) POM (NC), tip shape: 0.8mmR). The load value at which the resistance measured by the tester stabilized was used as the input start load.

[0217] like Figure 7 As shown in the enlarged view, the position 12 where the load is applied with a pen is set to the central area of ​​four dot-shaped spacers 11 arranged in a grid pattern on the surface of the ITO glass substrate 10. Furthermore, the input starting load is obtained by measuring the average of any three points at least 50 mm away from the double-sided tape. The first decimal place is rounded.

[0218] In addition, another evaluation panel was produced by the same method as described above, and the input start load was measured. When the first digit after the decimal point was rounded off, in the case where the two input start loads were identical, the input start load was evaluated to be stable, and one value was shown in Table 6. On the other hand, in the case where the two input start loads were not identical, the two results were shown in Table 6.

[0219] (14) Voltage loss time measurement (test method 2)

[0220] A constant voltage power source was connected to the evaluation panel produced in the input start load measurement. Next, a recorder (KEYENCE Co., Ltd., 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 time change in voltage. Next, 6 V was applied to the constant voltage power source, and the recorder was started to measure the voltage at a rate of 0.02 milliseconds. Next, a pen made of polyacetal (Toray Plastics Precision Co., Ltd., product name: TPS (registered trademark) POM (NC), shape of the tip: 0.8 mmR) was applied to the transparent conductive film at a rate of 50 g for 5 times in 1 second from the transparent conductive film side. The position at which the pen applied the load was the center of the evaluation panel, which was the center region of the four dot-shaped spacers arranged in a lattice shape. The data of the time change in voltage when the pen applied the load to the transparent conductive film was extracted from the recorder. The time from when the pen started to move away from the transparent conductive film and the voltage started to decrease from 6 V to when the voltage reached 5 V was measured as the voltage loss time and was recorded (see Figure 5 ).

[0221] (15) Adaptability to input strength test (anti-misinput property, comfortable input property)

[0222] A resistance film type touch panel was produced using the transparent conductive film obtained in the examples and the comparative examples. A pen made of polyacetal (Toray Plastics Precision Co., Ltd., product name: TPS (registered trademark) POM (NC), shape of the tip: 0.8 mmR) was used to investigate the input strength.

[0223] (Anti-misinput property)

[0224] O… Few inputs when touching the touch panel while being confused.

[0225] X… Many inputs when touching the touch panel while being confused.

[0226] (Comfortable input property)

[0227] O… Can be input even without intentionally applying a large force.

[0228] Δ… Unstable behavior.

[0229] X…Sometimes cannot be inputted without intentionally applying a large force.

[0230] (16) Input stability (stability of strokes, speed of writing)

[0231] A resistive film type touch panel was produced using the transparent conductive film obtained in the use examples and the comparative examples. The input stability was investigated using a pen made of a polyacetal.

[0232] (stability of strokes)

[0233] O…When inputting characters, the strokes are not easily broken.

[0234] X…When inputting characters, the strokes are easily broken.

[0235] (speed of writing)

[0236] O…When continuously inputting characters, characters are not easily broken.

[0237] X…When continuously inputting characters, characters are easily broken.

[0238] (17) Pen sliding durability (test method 6)

[0239] Using the transparent conductive film as one panel, as the other panel, an indium-tin composite oxide film (tin oxide content: 10 mass%) having a thickness of 20 nm was formed on one surface of a glass substrate by a sputtering method. In the production of the above-mentioned other panel, specifically, a glass substrate (thickness: 1.1 mm, size: 5 cm x 6 cm) was put into a vacuum chamber, and vacuumed to 1.5 x 10 -4 Pa. Next, after introducing oxygen, argon was introduced so that the total pressure was 0.6 Pa. The flow ratio of oxygen to argon was set to 0.033. A sintered target of indium-tin composite oxide (tin oxide content: 10 mass%) was put into power at a power density of 3 W / cm 2 2, and an indium-tin composite oxide conductive film (tin oxide content: 10 mass%) having a thickness of 20 nm was formed on one surface of the glass substrate by a DC magnetron sputtering method. The glass substrate after the film formation was heated at 230°C in air for 1 hour. On the surface of the conductive film formed on one surface of the glass substrate, microbeads (diameter: 30 μm) of an epoxy resin (Toyo Gosei Co., Ltd., product name: CR-102C-23) were formed in a square lattice shape at a pitch of 4 mm as shown in Figure 8 The transparent conductive film (size: 5 cm x 6 cm) obtained in the use examples or the comparative examples was overlaid on the ITO glass substrate with the transparent conductive film facing each other. At the time of the overlaying, the glass substrate was fixed to the transparent conductive film with a double-sided tape (3M Co., product name: 468MP) so that the glass substrate and the transparent conductive film were not in contact with each other. Figure 9As shown, the transparent conductive film 20 and the ITO glass substrate 10 align their respective end portions 16 in a manner orthogonal to the length direction, and the length direction single-side end portion 18 of the transparent conductive film 20 and the length direction single-side end portion 17 of the ITO glass substrate 10 extend from the overlapping surface 19 in a manner that the extended portions 17, 18 are connected to the tester. Next, a pen made of polyacetal (Toray Plastics Precision Co., Ltd., product name: TPS (registered trademark) POM (NC), shape of the tip: 0.8 mm R) was subjected to a 50,000-time reciprocating linear sliding test with a load of 2.5 N applied thereto. The sliding distance at this time was set to 30 mm, and the sliding speed was set to 180 mm / sec. As shown in the enlarged view of a part of the figure, Figure 8 As shown in the enlarged view of a part of the figure, the position 21 of the sliding was between the dot-shaped spacers 11 arranged in a lattice shape on the surface of the ITO glass substrate 10. After this sliding durability test, the ON resistance (resistance value when the movable electrode (film electrode) and the fixed electrode are in contact) was measured when the sliding portion was pressed with a load of 0.8 N by the pen. The ON resistance is more preferably 10 kΩ or less.

[0240] 2. Laminated film

[0241] In the column of Examples, a laminated film including a transparent plastic film substrate, a curable resin layer, and a functional layer was used.

[0242] (1) Substrate (transparent plastic film substrate): a biaxially oriented transparent PET film (Toyo Rika Co., Ltd., A4380, thickness described in Table 1) having an easy-adhesion layer on both sides.

[0243] (2) Curable resin layer: 100 parts by mass (solid content) of an acrylic resin (Dai-Nippon Ink and Chemicals, Inc., SEIKA BEAM (registered trademark) EXF-01J) containing a photopolymerization initiator was mixed with silica particles (Particle A, Particle B) having the number average particle diameters described in Table 1 in the amounts described in Table 1. Note that the amounts of the particles described in Table 1 indicate the amounts relative to 100 mass% of the solid content of the resin. A mixed solvent of toluene / methyl ethyl ketone (MEK) (8 / 2: mass ratio) was added so that the solid content concentration became the values of Table 1, and stirring was performed to uniformly disperse the mixture, thereby preparing a coating liquid (coating liquid A). The prepared coating liquid A was coated on one side of the transparent plastic film substrate using a Mayer bar so that the thickness of the coating film became the values described in Table 1. After drying at 80°C for 1 minute, ultraviolet rays were irradiated using an ultraviolet irradiation device (EYE GRAPHICS Co., Ltd., UB042-5AM-W type) (light amount: 300 mJ / cm 2 ), and the coating film was cured.

[0244] (3) Functional layer: In 100 parts by mass (solid content) of an acrylic resin (manufactured by SEKABEAM (registered trademark) EXF-01J) containing a photopolymerization initiator, the number average particle diameter of silica particles (Particle C) described in Table 2 was mixed in the amount described in Table 2. Note that the amount of the particles described in Table 2 indicates the amount relative to 100 mass% of the solid content of the resin. A mixed solvent of toluene / MEK (8 / 2: mass ratio) was added as a solvent so that the solid content concentration became the value of Table 2, and stirring was performed to uniformly disperse it, thereby preparing a coating liquid (Coating liquid C). The prepared coating liquid C was coated on the surface of the transparent plastic film substrate on the side opposite to the above-mentioned cured resin layer using a Meyer bar so that the thickness of the coating film became the value described in Table 2. After drying at 80°C for 1 minute, ultraviolet rays were irradiated using an ultraviolet irradiation device (manufactured by EYE GRAPHICS, model UB042-5AM-W) to cure the coating film. 2

[0245] Examples 1 to 8

[0246] In a vacuum tank, the laminated film was put in, and vacuumed to 1.5 x 10 -4 Pa. Next, after introducing oxygen, argon was introduced so that the total pressure became 0.6 Pa. The flow rate ratio of oxygen to argon is shown in Table 3.

[0247] As shown in Figure 6 , for the cured resin layer of the laminated film (treated film) 1 on the center roll 2, a transparent conductive film was formed from a target 4 inside a shield 3 by sputtering. The target 4 used a sintered target of indium-tin composite oxide, or a sintered target of indium oxide not containing tin oxide, and was inputted with electric power at a power density of 3 W / cm 2 , and a transparent conductive film was formed by a DC magnetron sputtering method. The film thickness was controlled by changing the speed of the film passing over the target.

[0248] In addition, the ratio of the water vapor pressure to argon in the film formation atmosphere at the time of sputtering was measured using a gas analysis device (manufactured by INFICON, Transpector XPR3), and is shown in Table 3. The ratio of the water vapor was adjusted as described in Table 3 by adjusting the presence or absence of a bombardment process, the presence or absence of a protective film, the unevenness of the film roll end surface, and the temperature of the temperature medium (Japanese: on-medi) of a temperature controller that controls the temperature of the center roll that the film contacts while traveling. In the above-mentioned bombardment process, SUS (stainless steel) was used as the target, and was inputted with electric power at a power density of 0.5 W / cm 2 ​RF sputtering was performed. The amount of the introduction gas of the RF sputtering was the same as the amount of the gas introduced into the vacuum device described in the examples. When a protective film was used, a polyethylene film having a thickness of 65 μm was used. An acrylic adhesive was applied to one side of the protective film. The protective film was attached to the side opposite to the side on which the transparent conductive film of the laminated film was formed. As for the temperature of the temperature medium, the temperature halfway between the maximum value and the minimum value of the temperature from the start of the film formation to the end of the film formation of the film roll was set to the value described in Table 3.

[0249] The transparent conductive film was formed under the conditions described in Table 3 using the laminated film produced under the conditions described in Tables 1 and 2. The transparent conductive film was produced in the same manner as in Examples 1 to 8 except that the transparent conductive film was formed under the conditions described in Table 3. The properties of the obtained film are shown in Tables 4 to 6.

[0250] For the obtained transparent conductive film, the film thickness, the crystallinity, the total light transmittance (%), the surface resistance (Ω / D), the adhesion to the transparent conductive film, and the adhesion to the functional layer were evaluated. The results are shown in Table 4.

[0251] For the obtained transparent conductive film, the stiffness (BR), the average maximum peak height (AVSp), the contact area ratio (CA), the maximum peak height upper side displacement ratio (MXSp / AVSp), and the maximum peak height lower side displacement ratio (MNSp / AVSp) were calculated. The results are shown in Table 5.

[0252] For the obtained transparent conductive film, the input start load, the voltage loss time, the adaptive input strength test (anti-misinput property, comfortable input property), the input stability (punctuation stability, shorthand property), and the pen slide durability were investigated. The results are shown in Table 6.

[0253] Comparative Examples 1 to 8

[0254] The transparent conductive film was formed under the conditions described in Table 3 using the laminated film produced under the conditions described in Tables 1 and 2, and the transparent conductive film was produced in the same manner as in Examples 1 to 8 except that. The properties of the obtained film are shown in Tables 4 to 6.

[0255]

[0256] [Table 2]

[0257] Table 2

[0258]

[0259]

[0260] [Table 4]

[0261] Table 4

[0262]

[0263]

[0264] [Table 6]

[0265] Table 6

[0266]

[0267] Industrial applicability

[0268] The transparent conductive film can be widely used in the field of electricity and electronics as a transparent electrode of a flat panel display such as a liquid crystal display, an electroluminescence (EL) display, and the like, a touch panel, and the like.

[0269] Explanation of reference numerals

[0270] 1 Film to be processed

[0271] 2 Center roll

[0272] 3 Shield

[0273] 4 Target

[0274] 5 Transparent conductive film

[0275] 6 Cured resin layer

[0276] 7 Transparent plastic film substrate

[0277] 8 Functional layer

[0278] 9 Easy-adhesive layer

[0279] 10 ITO glass substrate

[0280] 11 Dot-like spacer

[0281] 12 Position where a load is applied with a pen

[0282] 13 Time

[0283] 14 Voltage

[0284] 15 Voltage loss time

[0285] 16 End portion

[0286] 17, 18 Extension portion

[0287] 19 Overlapping surface

[0288] 20 Transparent conductive film

[0289] 21 Sliding position

Claims

1. A transparent conductive film which is a transparent conductive film in which at least one surface of a transparent plastic film substrate is laminated with an indium-tin composite oxide transparent conductive film, and which has a cured resin layer containing particles B having a number average particle diameter of 0.01 μm or more and less than 1.0 μm between the transparent plastic film substrate and the transparent conductive film, the input start load obtained by Test Method 1 is greater than 15 g and 25 g or less, the voltage loss time obtained by Test Method 2 is 0.00 milliseconds or more and 0.40 milliseconds or less, the film stiffness BR obtained by Test Method 3 is 0.38 N-cm or more and 0.90 N-cm or less, the average value AVSp of the maximum peak height Sp of the conductive surface obtained by Test Method 4 satisfies the following formula (2-1), the contact area ratio CA obtained by Test Method 5 satisfies the following formula (2-3), 4.7 x BR - 3.6 ≤ AVSp < 4.7 x BR - 1.8... Formula (2-1), CA ≥ 32.6 x BR + 17.2... Formula (2-3), where BR is the film stiffness, AVSp is the average maximum peak height, and CA is the contact area ratio; Test Method 1 A glass substrate was formed with a 20-nm-thick indium-tin composite oxide conductive film having a tin oxide content of 10 mass% on one surface, and a panel was produced by forming a dot-shaped spacer of an epoxy resin having a length of 60 μm x width of 60 μm x height of 5 μm in a square lattice pattern at intervals of 4 mm on the surface of the thin film. An evaluation panel was produced by overlapping a transparent conductive film on the conductive film side of the panel while sandwiching a rectangular frame having an adhesive property having a thickness of 105 μm and an inner circumference of 190 mm x 135 mm in such a manner that the conductive films faced each other. The pressure at which the resistance value became stable was measured as the input start load by pressing the center of the 4-dot lattice of the dot-shaped spacer from the transparent conductive film side of the evaluation panel with a pen having a hemispherical tip with a radius of 0.8 mm. Test Method 2 The evaluation panel was connected to a constant voltage power source of 6 V, and the center of the 4-dot lattice of the dot-shaped spacer was pressed from the transparent conductive film side at an interval of 5 times / second with a load of 50 gf using a pen having a hemispherical tip with a radius of 0.8 mm. The time until the voltage reached 5 V was measured as the voltage loss time, starting from when the pen started to move away from the transparent conductive film and the voltage decreased from 6 V. Test Method 3 A 20 mm x 250 mm transparent conductive film test piece was placed on a water platform with the transparent conductive film facing upward, and the test piece was made to protrude from the end of the platform by a length of 230 mm. The stiffness BR was determined based on the following formula. Stiffness BR = g x a x b x L 4 / (8 x delta x 10 11 ) wherein g is 9.81, which is the acceleration of gravity, in m / s 2 a is 20, which is the length of the short side of the test piece, in mm, b indicates the specific gravity of the test piece, in g / cm 3 L is 230, which is the length of the long side of the test piece exposed to the water table, in mm, and δ indicates the difference between the height of the front end of the test piece and the height of the table, in cm; Test Method 4 In the conductive surface of the transparent conductive film, 3 points were determined at intervals of 1 cm in the MD direction, and 2 points were determined symmetrically in the TD direction at intervals of 1 cm from the center of the 3 points, for a total of 5 measurement points. The maximum peak height Sp based on surface roughness was measured at each position in accordance with ISO 25178, and the average value thereof was taken as the average maximum peak height AVSp. Test Method 5 For the conductive surface of the transparent conductive film, the average height Rc based on line roughness, the maximum peak height Rp, and the average length Rsm were measured, and the arithmetic average height Ra based on line roughness was measured at a site satisfying at least one of Expression (X1) and Expression (X2) and Expression (X3); note that the average height Rc, the maximum peak height Rp, the average length Rsm, and the arithmetic average height Ra were determined using a three-dimensional surface shape measuring device VertScan, which is R5500H-M100 manufactured by Ryoka Systems Co., Ltd., under the following measurement conditions: wave mode, measurement wavelength 560 nm, objective lens 50x; the maximum peak height Rp, the average length Rsm, and the arithmetic average height Ra were determined in accordance with the provisions of JIS B 0601-2001; the measurement length of the arithmetic average height Ra was set to 100 μm or more and 200 μm or less, Rp - Rc - Ra ≤ 0.20... Expression (X1) (Rp - Rc) / Ra ≤ 5.0... Expression (X2) Rsm ≤ 30... Expression (X3) The objective lens of the three-dimensional surface shape measuring device VertScan was changed to 10 times, and particle analysis based on the measuring device was used to slice in the planar direction at a height of "arithmetic average height Ra - 15 x 10 -3 μm - average height Rc" from the average plane, and the sum of the cross-sectional areas was calculated. The value obtained by dividing the sum of the cross-sectional areas by the area of the measuring field and multiplying by 100 was taken as the contact area ratio CA. The unit of BR is N·cm, the unit of AVSp is μm, the unit of CA is %, the units of Rc, Rp, and Rsm are μm, and the unit of Ra is μm.

2. The transparent conductive film according to claim 1, wherein The average value AVSp of the maximum peak height Sp of the conductive surface obtained by the test method 4 satisfies the following Expression (2-2), 0.005 ≤ AVSp ≤ 12.000... Expression (2-2) In the expression, AVSp is the average maximum peak height.

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

4. The transparent conductive film according to any one of claims 1 to 3, wherein The thickness of the transparent conductive film is 10 nm or more and 100 nm or less.

5. The transparent conductive film according to any one of claims 1 to 3, wherein The concentration of tin oxide contained in the transparent conductive film is 0.5 mass% or more and 40 mass% or less.

6. The transparent conductive film according to any one of claims 1 to 3, wherein A functional layer is provided on the side opposite to the transparent conductive film of the transparent plastic film substrate.

7. The transparent conductive film according to 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 according to claim 6, wherein An easy-adhesion layer is provided on at least one side of the transparent plastic film substrate, The easy-adhesion layer is provided at at least one of the positions between the transparent plastic film substrate and the curable resin layer or between the transparent plastic film substrate and the functional layer.

9. The transparent conductive film according to any one of claims 1 to 3, wherein The ON resistance determined by the test method 6 is 10 kΩ or less, Test method 6 An evaluation panel was produced by overlapping a panel in which an indium-tin composite oxide conductive film having a thickness of 20 nm and a tin oxide content of 10 mass% was formed on one side of a glass substrate with a transparent conductive film with an epoxy microbead having a diameter of 30 μm such that the conductive films faced each other, and on the side of the transparent conductive film of the evaluation panel, a load of 2.5 N was applied while sliding with a pen having a half-sphere with a radius of 0.8 mm at the tip, the number of reciprocating times was 50,000 times, the sliding distance was 30 mm, and the sliding speed was 180 mm / sec. After the sliding, the resistance when the sliding portion was pressed with a load of 0.8 N to be electrically connected, i.e., the ON resistance, was measured.

10. The transparent conductive film according to any one of claims 1 to 3, wherein In the adhesion test according to JIS K5600-5-6:1999 on the surface of the transparent conductive film, the residual area rate of the transparent conductive film was 95% or more.

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