Conductive film, touch panel, photosensitive resin composition, and method for manufacturing conductive film

Abstract

The present invention provides a conductive film capable of suppressing disconnection of a metal wiring and bending a wiring portion of a conductive film, a touch panel, a photosensitive resin composition, and a method for manufacturing the conductive film. The conductive film includes a cured film formed from the photosensitive resin composition as a protective layer for a lead wiring portion of the conductive film that functions as a touch sensor, and the photosensitive resin composition includes at least one monomer represented by formula (1) and formula (2), a clay mineral, and a photopolymerization initiator.

Description

Technical Field

[0001] The present invention relates to a conductive film, a touch panel, and a photosensitive resin composition capable of being used as a wiring protective layer for a conductive film, which have excellent durability against sulfur or halogen in the environment and iodine eluted from a polarizing plate and function as a touch sensor having thinning and flexibility. Background Art

[0002] Currently, there is a touch panel that is used in combination with a display device such as a liquid crystal display device or an organic EL display device in various electronic devices such as mobile information devices such as tablet computers and smartphones, and inputs an operation to the electronic device by touching the screen. The touch panel has a touch sensor, and the touch sensor includes a detection electrode for detecting a touch and a lead wiring electrically connected to the detection electrode.

[0003] The lead wiring extracts an electrical signal from the detection electrode, runs around the detection electrode, and is arranged to a position connected to an FPC (flexible printed circuit board). At the connection portion with the FPC, the FPC is electrically connected to the lead wiring and is connected to an IC (integrated circuit) that controls the touch sensor through the FPC. Thus, the touch sensor can be driven.

[0004] In recent years, thinning and narrow bezeling of touch panels have been continuously carried out. By thinning the touch panel, the battery capacity of the electronic device can be increased. By narrowing the bezel of the touch panel, the area occupied by the screen display of the touch panel becomes wider, the actual usable screen size increases, and it becomes a design with high design aesthetics.

[0005] On the other hand, due to the narrow bezeling of the touch panel, the interval between the lead wirings becomes narrow, and there is a problem that migration is likely to occur. In Patent Document 1, a protective layer containing an epoxy resin is provided on the lead wiring to suppress migration.

[0006] In Patent Document 2, an actinic ray-curable resin composition containing talc is described as an insulator having excellent adhesion to a transparent electrode or the like of a touch panel.

[0007] Moreover, for narrow bezeling, for example, in Patent Document 3, a flexible substrate is used to bend the wiring.

[0008] A touch sensor is described in Patent Document 3, which has: a substrate having a plurality of regions, at least including a planar region and a side region that is continuous with the planar region and bent with respect to the planar region; a touch sensor unit provided in the planar region of the substrate; and an antenna provided in a region different from the planar region of the substrate. The substrate is made of a flexible transparent substrate, and the touch sensor unit includes a detection unit and a peripheral wiring unit, and at least the detection unit is composed of fine metal wires.

[0009] Prior Art Documents

[0010] Patent Documents

[0011] Patent Document 1: Japanese Patent Application Laid-Open No. 2014-182436

[0012] Patent Document 2: Japanese Patent Application Laid-Open No. 2004-331769

[0013] Patent Document 3: WO 2016 / 158085 Summary of the Invention

[0014] Technical Problem to be Solved by the Invention

[0015] In order to make the touch panel thinner, it is required that the thicknesses of the transparent insulating layers that bond the components constituting the touch panel, such as optical clear adhesives (OCAs) and optical clear resins (OCRs) such as UV (ultraviolet: extreme ultraviolet) curable resins, are also thinned, and the conductive film does not have large protrusions so as not to impair the step difference followability.

[0016] Moreover, in order to narrow the bezel, not only the interval between the lead wirings of the touch panel needs to be narrowed, but also the line width needs to be narrowed. If the line width of the lead wiring is narrowed, the probability of disconnection due to corrosion of the wiring caused by sulfur, halogens, etc. in the external environment becomes high. In particular, in a touch panel combined with a liquid crystal display device or an organic EL display device, it has been found that iodine contained in the polarizer of the display device promotes the disconnection of the lead wiring.

[0017] Furthermore, in order to narrow the bezel of the touch panel, attempts have been made to bend the wiring portion along the edge portion of the display device. During this period, the thickness of the display device itself has also become thinner. Therefore, when bending along the edge portion of the display device, it is required to bend with a curvature radius of 2 mm or less.

[0018] In the above Patent Document 1, the water permeability of the resin for the protective layer is high, and it is impossible to suppress the disconnection of the lead wiring. Moreover, if an attempt is made to suppress the disconnection by increasing the thickness of the protective layer, while the thickness of the touch panel increases, it is difficult to bend the wiring portion as described in Patent Document 3 to achieve bezel narrowing.

[0019] Further, as described above, Patent Document 2 describes that a resin composition having excellent adhesion is coated on the lead-out wiring. However, it is not sufficient to protect the lead-out wiring of the touch panel from sulfur and halogens (especially iodine) in a region where the thickness of the resin layer is thin.

[0020] An object of the present invention is to solve the problems of the foregoing prior art and to provide a conductive film and a touch panel including the conductive film. Even when the thickness of the metal wiring protective layer is thin, the conductive film can suppress the disconnection of the metal wiring and can bend the wiring portion with a small curvature. Another object of the present invention is to provide a photosensitive resin composition and a manufacturing method for manufacturing the conductive film.

[0021] Means for Solving the Technical Problem

[0022] In order to achieve the above object, as a result of intensive experimental research by the present inventors, it has been found that the above object can be achieved by the following structure.

[0023] The present invention provides a conductive film having a metal wiring portion on at least one surface of a transparent flexible substrate. At least a part of the wiring portion is covered with a protective layer having a thickness (t) of 15 μm or less formed by curing a photosensitive resin composition. The photosensitive resin composition contains a resin forming component including at least one (meth)acrylate monomer represented by the following formula (1) or formula (2), a clay mineral, and a photopolymerization initiator. The average particle diameter (D ave ) of the clay mineral is 1 / 5 to 1 / 2 or less of the thickness (t), and the average aspect ratio is 2.0 or more. The proportion of the clay mineral having a particle diameter of the thickness (t) or more is 0.5% by volume or less, and the proportion of the clay mineral contained in the photosensitive resin composition is 5 to 50% by mass.

[0024] [Chemical Formula 1]

[0025]

[0026]

[0027] (In the formula, R 1 , R 2 each represent a (meth)acryloyl group. R 3 represents an unsubstituted or substituted (meth)acryloyl group. X represents a single bond or a divalent linking group represented by the following formula (3).)

[0028] Formula (3): -Y 1 -R 4 -Y 2 -

[0029] (In the formula, R4 represents an alkylene group having 3 or less carbon atoms. Y 1 , Y 2 each represents an oxygen atom or a single bond.)

[0030] Preferably, the average particle size of the clay mineral is less than 2.5 μm, and the thickness of the protective layer is 8 μm or less.

[0031] Preferably, the photosensitive resin composition contains 10 to 30% by mass or more of the clay mineral.

[0032] The clay mineral is preferably talc surface-modified with a silane coupling agent having a functional group capable of crosslinking with the resin-forming components.

[0033] The functional group is preferably at least one selected from the group consisting of (meth)acryloyl, vinyl, epoxy, styryl, amino, mercapto, and isocyanate groups.

[0034] The resin component preferably further contains an oligomer and / or a polymer.

[0035] The oligomer and the polymer are preferably (meth)acrylates.

[0036] Furthermore, the present invention provides a conductive film having a wiring portion formed of a metal conductive layer on at least one surface of a transparent flexible substrate, wherein a protective layer having a thickness (t) of 15 μm or less and containing a resin component having a dicyclopentene structure or a tricyclodecane structure and a clay mineral is laminated on at least a part of the wiring portion, the average particle size (D ave ) of the clay mineral is 1 / 2 or less of the thickness (t), the average aspect ratio is 2.0 or more, and the proportion of the clay mineral having a particle size of the thickness (t) or more is 0.5% by volume or less, and the proportion of the clay mineral contained in the protective layer is 5 to 50% by mass.

[0037] The present invention provides a touch panel in which an image display module, the aforementioned conductive film, and a covering portion are laminated in this order, and the conductive film is disposed on the display surface side of the image display module, wherein a polarizing plate is further disposed between at least one of the image display module and the conductive film and between the conductive film and the covering portion.

[0038] Preferably, at least a part of the wiring portion is bent along the edge portion of the image display module.

[0039] Furthermore, the present invention provides a photosensitive resin composition containing:

[0040] A resin-forming component containing at least one (meth)acrylate monomer represented by the following formula (1) and formula (2); a clay mineral having an average particle diameter of 7.5 μm or less and an average aspect ratio of 2.0 or more, and surface-modified with a silane coupling agent having a functional group capable of crosslinking with the resin-forming component; and a photopolymerization initiator. The viscosity of the photosensitive resin composition is 5000 mPa·s or more, and the proportion of the clay mineral contained in the photosensitive resin composition is 5 to 50% by mass.

[0041] [Chemical formula 2]

[0042]

[0043]

[0044] (In the formula, R 1 , R 2 each represent a (meth)acryloyl group. R 3 represents an unsubstituted or substituted (meth)acryloyl group. X represents a single bond or a divalent linking group represented by the following formula (3).)

[0045] Formula (3): -Y 1 -R 4 -Y 2 -

[0046] (In the formula, R 4 represents an alkylene group having 3 or fewer carbon atoms. Y 1 , Y 2 each represent an oxygen atom or a single bond.)

[0047] Furthermore, the present invention provides a method for manufacturing a conductive film, which includes: a step of forming a wiring portion composed of a metal conductive layer on at least one surface of a transparent flexible substrate; a step of determining the designed thickness of the protective layer to cover at least a part of the metal fine wire and be 15 μm or less; a step of applying the photosensitive resin composition to at least a part of the metal fine wire, the photosensitive resin composition containing a resin-forming component containing at least one (meth)acrylate monomer represented by formula (1) and formula (2), a clay mineral having an average particle diameter of 1 / 5 to 1 / 2 of the designed thickness, a proportion of the clay mineral having a particle diameter of the designed thickness or more of 0.5% by volume or less, and an average aspect ratio of 2.0 or more, and a photopolymerization initiator; and a step of curing the photosensitive resin composition to form a protective layer having the same thickness as the designed thickness. The proportion of the clay mineral contained in the photosensitive resin composition is 5 to 50% by mass, and the viscosity of the photosensitive resin composition is 5000 mPa·s or more.

[0048] [Chemical formula 3]

[0049]

[0050]

[0051] (wherein, R 1 , R 2 each represents (meth)acryloyl. R 3 represents an unsubstituted or substituted (meth)acryloyl. X represents a single bond or a divalent linking group represented by the following formula (3).)

[0052] Formula (3): -Y 1 -R 4 -Y 2 -

[0053] (wherein, R 4 represents an alkylene group having 3 or less carbon atoms. Y 1 , Y 2 each represents an oxygen atom or a single bond.)

[0054] Advantages of the Invention

[0055] According to the present invention, there can be provided a conductive film, a touch panel, a photosensitive resin composition, and a method for manufacturing a conductive film, which can suppress disconnection of metal wirings and can bend a wiring portion of the conductive film. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 is a schematic cross-sectional view showing a first example of a touch panel according to an embodiment of the present invention.

[0057] Figure 2 is a schematic cross-sectional view showing a second example of a touch panel according to an embodiment of the present invention.

[0058] Figure 3 is a schematic cross-sectional view showing a third example of a touch panel according to an embodiment of the present invention.

[0059] Figure 4 is a schematic view showing a first example of a conductive film according to an embodiment of the present invention.

[0060] Figure 5 is a schematic view showing a second example of a conductive film according to an embodiment of the present invention.

[0061] Figure 6 is a schematic cross-sectional view showing the structure of a detection portion of a conductive film according to an embodiment of the present invention.

[0062] Figure 7 is a schematic view showing the electrode structure of a detection portion of a conductive film of a touch panel according to an embodiment of the present invention.

[0063] Figure 8It is a schematic diagram showing an example of the shape of the grid pattern of the detection part of the conductive film of the touch panel showing an embodiment of the present invention.

[0064] Figure 9 It is a schematic cross-sectional view showing an example of the structure of the detection part of the conductive film showing an embodiment of the present invention.

[0065] Figure 10 It is a schematic diagram showing an enlarged view of an example of the metal fine wire of the detection part showing an embodiment of the present invention. Detailed Embodiments

[0066] Hereinafter, the conductive film, touch panel, and photosensitive resin composition of the present invention will be described in detail.

[0067] In addition, the drawings described below are illustrative drawings for explaining the present invention, and the present invention is not limited to the drawings shown below.

[0068] In addition, "~" indicating a numerical range hereinafter includes the numerical values described on both sides. For example, when ε is a numerical value α~numerical value β, it means that the range of ε is a range including the numerical values α and β, and in mathematical symbols, it is α≤ε≤β.

[0069] Unless otherwise specified, angles such as "parallel" and "orthogonal" include the error ranges generally allowed in the corresponding technical field.

[0070] Moreover, "the same" includes the error ranges generally allowed in the corresponding technical field.

[0071] Moreover, light means actinic rays or radiation. Unless otherwise specified, "exposure" in this specification includes not only exposure based on the bright line spectrum of a mercury lamp, far ultraviolet rays typified by excimer lasers, X-rays, EUV light, etc., but also drawing based on particle beams such as electron beams and ion beams is included in the exposure.

[0072] Moreover, "(meth)acrylate" means both or either of acrylate and methacrylate, and "(meth)acrylic acid" means both or either of acrylic acid and methacrylic acid. Moreover, "(meth)acryloyl" means both or either of acryloyl and methacryloyl.

[0073] In addition, unless otherwise specified, transparent means that the light transmittance is 40% or more, preferably 80% or more, and more preferably 90% or more in the visible light wavelength region of wavelengths 380~780 nm.

[0074] The light transmittance is a value measured by "Plastics - Method for Measuring Total Light Transmittance and Total Reflectance" specified in JIS (Japanese Industrial Standards) K 7375:2008.

[0075] (Touch Panel)

[0076] Figure 1 It is a schematic cross-sectional view of a touch panel showing the first example of the embodiment of the present invention.

[0077] In the touch panel 10 of the first example, an image display module 12, a first transparent insulating layer 17a, a polarizing plate 14, a second transparent insulating layer 17b, a conductive film 11, a third transparent insulating layer 17c, and a covering portion 15 are stacked in sequence, and the conductive film 11 is disposed on the display surface side of the image display module 12.

[0078] In the touch panel 10, the surface of the covering portion 15 is the touch surface of the touch panel 10 and becomes the operation surface. The touch panel 10 performs an input operation with the surface of the covering portion 16 as the operation surface. In addition, the touch surface refers to the surface where contact of a finger or a stylus is detected. The surface of the covering portion 16 becomes the visual recognition surface of a display object (not shown) displayed on the display surface of the image display module 12.

[0079] A controller 13 is provided on the back surface of the image display module 12. The flexible circuit board 19 connected to the conductive film 11 is bent to surround the side surface of the image display module 12. The conductive film 11 and the controller 13 are electrically connected through the flexible circuit board 19.

[0080] Figure 2 It is a schematic cross-sectional view of a touch panel showing the second example of the embodiment of the present invention.

[0081] In the touch panel of the second example, an image display module 12, a first transparent insulating layer 17a, a conductive film 11, a second transparent insulating layer 17b, a polarizing plate 14, a third transparent insulating layer 17c, and a covering portion 15 are stacked in sequence, and the conductive film 11 is disposed on the display surface side of the image display module 12.

[0082] Figure 3 It is a schematic cross-sectional view of a touch panel showing the third example of the embodiment of the present invention.

[0083] In the touch panel of the third example, an image display module 12, a first transparent insulating layer 17a, a polarizing plate 14, a second transparent insulating layer 17b, a conductive film 11, a third transparent insulating layer 17c, and a covering portion 15 are stacked in sequence, and a conductive film is disposed on the display surface side of the image display module 12.

[0084] A controller 13 is provided on the back surface of the image display module 12. The conductive film 11 is bent to surround the side surface of the image display module 12. The conductive film 11 and the controller 13 are electrically connected through the flexible circuit board 19. The conductive film 11 and the flexible circuit board 19 are connected on the back surface of the image display module.

[0085] In the structure of a conventional touch panel, as Figures 1 to 3As shown in the structure of the touch panel 10, the conductive film 11 and the polarizing plate 14 are arranged adjacent to each other and are further brought closer as the touch panel is thinned. It has been found that when the touch panel is used in an environment with high humidity and a large temperature difference between cold and warm, condensation often occurs around the touch panel, causing iodine to dissolve out from the polarizing plate 14 and promoting the corrosion of the metal wiring of the conductive film 11.

[0086] Moreover, as the touch panel has a narrow bezel, in the structure where the wiring part is bent along the edge part of the image display module Figure 3 shown, while the wiring part is stressed, the wiring part is exposed, which will further promote the corrosion of the metal wiring caused by sulfur, halogen, etc. in the external environment.

[0087] The image display module 12 has a display surface for displaying display objects such as images. For example, a liquid crystal display device, an organic EL (Organic electro luminescence) display device, a cathode ray tube (CRT) display device, a vacuum fluorescent display (VFD), a plasma display panel (PDP), a surface field emission display (SED), a field emission display (FED), and an electronic paper can be used.

[0088] In order to form the thickness of the touch panel 10 thinner, it is preferably in the form of a panel such as a liquid crystal display panel and an organic EL panel.

[0089] (Conductive film)

[0090] <Structure of the conductive film>

[0091] The conductive film 11 will be described.

[0092] Figure 4 and Figure 5 are schematic diagrams showing examples of the conductive film of the embodiment of the present invention. In Figure 4 the shown conductive film 11, the structure is such that the flexible circuit board 19 is bent instead of bending the conductive film 11. On the other hand, in Figure 5 the shown conductive film 11, the structure is to bend the bent part 25 extending from one end of the conductive film 11.

[0093] The conductive film 11 functions as a touch sensor in the touch panel 10. The conductive film 11 is a conductive film having metal wiring (for example, lead-out wiring 23) on the surface of a transparent flexible substrate 21, and at least a part of the metal wiring is covered with a protective layer 18 having a thickness of 8 μm or less.

[0094] For example, the conductive film 11 has a detection unit 20 formed of a conductive layer on at least one surface of the transparent flexible substrate 21, and a lead wiring unit 22 having one end electrically connected to the detection unit 20 and the other end connected to an external connection terminal 26. In the conductive film 11, the detection unit 20 and the lead wiring unit 22 are provided on the front surface 21a and the back surface 21b of the flexible substrate 21, respectively.

[0095] The detection unit 20 is an input area where a user can perform an input operation. The lead wiring unit 22 is arranged in an outer area located outside the input area. The input area of the detection unit 20 is referred to as an active area, and the outer area of the input area is referred to as a passive area.

[0096] At least a part of the surface of the lead wiring unit 22 is covered by the protective layer 18 to suppress corrosion caused by sulfur or halogen in the external environment or iodine eluted from the polarizing plate. From the viewpoint of suppressing corrosion, it is preferable to completely cover the lead wiring unit 22.

[0097] The detection unit 20 has, for example, a plurality of first detection electrodes 30 and a plurality of second detection electrodes 32. The plurality of first detection electrodes 30 are strip-shaped electrodes extending in parallel along the X direction, and are arranged on the front surface 21a of the flexible substrate 21 (refer to Figure 4 ) in a state of being electrically insulated from each other in the Y direction with an interval 31 therebetween in the Y direction orthogonal to the X direction. The plurality of second detection electrodes 32 are strip-shaped electrodes extending in parallel along the Y direction, and are arranged on the back surface 21b of the flexible substrate 21 (refer to Figure 4 ) in a state of being electrically insulated from each other in the X direction with an interval 31 therebetween in the X direction. The plurality of first detection electrodes 30 and the plurality of second detection electrodes 32 are arranged orthogonally to each other, but are electrically insulated from each other through the flexible substrate 21.

[0098] In addition, the interval 31 between the first detection electrode 30 and the second detection electrode 32 is an area that is cut off from the first detection electrode 30 or the second detection electrode 32 and is not electrically connected. Therefore, as described above, the plurality of first detection electrodes 30 are in a state of being electrically insulated from each other in the Y direction, and the plurality of second detection electrodes 32 are in a state of being electrically insulated from each other in the X direction.

[0099] As Figure 4 shown, in the detection unit 20, five first detection electrodes 30 are provided and five second detection electrodes 32 are provided, but the number thereof is not particularly limited as long as there are a plurality of them.

[0100] The first detection electrode 30 and the second detection electrode 32 are formed of, for example, metal fine wires 33 (refer to Figure 7 ). The metal fine wires 33 are arranged in a mesh pattern, for example. The pattern of the metal fine wires 33 will be described in detail later. Both the first detection electrode 30 and the second detection electrode 32 correspond to the conductive layer.

[0101] The lead wiring portion 22 is a component that functions to apply voltage to the first detection electrode 30 and the second detection electrode 32. One end of the lead wiring portion 22 is electrically connected to the first detection electrode 30 or the second detection electrode 32. An external connection terminal 24 is provided at the terminal portion as the other end.

[0102] The lead wiring portion 22 is composed of a plurality of lead wirings 23. One end of each lead wiring 23 is electrically connected to the above-mentioned first detection electrode 30 or second detection electrode 32. The other ends of the lead wirings 23 are collectively electrically connected to one external connection terminal 24. The other ends of the plurality of lead wirings 23 are the terminal portion of the lead wiring portion 22.

[0103] In addition, the number of lead wirings 23 of the lead wiring portion 22 is the same as the number of detection electrodes to which they are electrically connected.

[0104] In Figure 4 In the touch panel 10 shown, the lead wiring portion 22 is electrically connected to the end portion in the X direction of the first detection electrode 30, and the lead wiring portion 22 is electrically connected to one end portion in the Y direction of the second detection electrode 32. The lead wiring portion 22 is arranged for the first detection electrode 30 and the second detection electrode 32 from three directions.

[0105] In addition, it is preferable that the detection portion 20 and the lead wiring portion 22 are of an integral structure. At this time, the detection portion 20 and the lead wiring portion 22 are formed by, for example, photolithography or the like.

[0106] Hereinafter, each component constituting the conductive film will be described.

[0107] <Electrode structure, etc.>

[0108] Figure 7 It is a schematic diagram showing an example of the electrode structure of the detection portion of the conductive film according to the embodiment of the present invention, Figure 8 It is a schematic diagram showing an example of the shape of the grid pattern of the detection portion of the conductive film of the touch panel according to the embodiment of the present invention.

[0109] As described above, the first detection electrode 30 and the second detection electrode 32 of the detection portion 20 are composed of metal fine wires 33. For example, as Figure 7 shown, the first detection electrode 30 and the second detection electrode 32 have a grid pattern formed by the intersection of a plurality of metal fine wires 33.

[0110] In addition, regarding the lead wiring 23, it can also be set to the same structure as the first detection electrode 30 and the second detection electrode 32. The lead wiring 23 is composed of straight lines, curves, and metal fine wires 33 combining these, and may also have a grid pattern formed by the intersection of a plurality of metal fine wires 33.

[0111] When the first detection electrode 30, the second detection electrode 32, and the lead wiring 23 are configured to have a mesh pattern, the pattern of the mesh pattern is not particularly limited, and is preferably a geometric figure formed by combining triangles such as equilateral triangles, isosceles triangles, and right triangles, quadrilaterals such as squares, rectangles, rhombuses, parallelograms, and trapezoids, (regular) n-gons such as (regular) hexagons and (regular) octagons, circles, ellipses, stars, etc.

[0112] As Figure 8 shown, the mesh of the mesh pattern refers to a shape including a plurality of openings 35 formed by intersecting fine metal wires 33.

[0113] The opening 35 is an opening area surrounded by the fine metal wire 33. Regarding the length W of one side of the opening 35, the upper limit is preferably 800 μm or less, more preferably 600 μm or less, and further preferably 400 μm or less, and the lower limit is preferably 5 μm or more, more preferably 30 μm or more, and further preferably 80 μm or more. When the length W of one side of the opening 35 is within the above range, transparency can be further maintained well, and when the conductive film 11 (refer to Figure 1 ) is mounted on the display surface of the image display module 12 (refer to Figure 1 ), the display can be visually recognized without a sense of incongruity.

[0114] From the aspect of visible light transmittance, the opening ratio of the mesh pattern is preferably 85% or more, more preferably 90% or more, and further preferably 95% or more. The opening ratio is the ratio of the transmissive part other than the fine metal wire, that is, the opening, in the region where the conductive layer is provided to the entire region where the conductive layer is provided.

[0115] As Figure 6 shown, in the detection unit 20, the first detection electrode 30 is provided on the surface 21a of the flexible substrate 21, and the second detection electrode 32 is provided on the back surface 21b. However, the structure is not limited to this. For example, the first detection electrode 30 and the second detection electrode 32 may be provided on different flexible substrates and laminated. Specifically, it may be a structure in which the flexible substrate 21 provided with the first detection electrode 30 and the flexible substrate 21 provided with the second detection electrode 32 are laminated via a transparent and electrically insulating insulator layer.

[0116] However, the structure in which the detection unit 20 is provided on the surface 21a and the back surface 21b of the flexible substrate 21 is not limited. As Figure 9 shown, it may also be a structure in which only one surface of the flexible substrate 21, for example, only the surface 21a, has the detection electrode 34. Figure 9 The detection electrode 34 shown functions as the detection unit 20. The detection electrode 34 is related to the first detection electrode 30 (refer to Figure 7)Similarly, it is composed of a plurality of fine metal wires 33, and the fine metal wires 33 are disposed on the surface 21a.

[0117] In addition, Figure 9 FIG. is a schematic cross-sectional view showing an example of the structure of a detection unit of a conductive film of a touch panel according to an embodiment of the present invention.

[0118] As a structure other than the fine metal wires, the first detection electrode 30 and the second detection electrode 32 of the detection unit 20 may be formed of conductive fibers such as silver nanowires, carbon nanotubes (CNT), carbon nanobuds (CNB), etc., may be formed of indium tin oxide (ITO), conductive polymers, or may be a combination thereof.

[0119] <Flexible substrate>

[0120] The flexible substrate refers to a material that can be bent. Specifically, it refers to a material that does not generate cracks even when bent with a curvature radius of 1 mm.

[0121] The flexible substrate is a support that supports the detection unit and the lead wiring unit and has flexibility. As the flexible substrate, as long as it can support the detection unit and the lead wiring unit and has flexibility, its type is not limited, and a transparent support is preferred, and a plastic sheet is particularly preferred.

[0122] As a specific example of the material constituting the flexible substrate, PET (polyethylene terephthalate) (258 ° C), polycycloolefin (134 ° C), polycarbonate (250 ° C), (meth) acrylic resin (128 ° C), PEN (polyethylene naphthalate) (269 ° C), PE (polyethylene) (135 ° C), PP (polypropylene) (163 ° C), polystyrene (230 ° C), polyvinyl chloride (180 ° C), polyvinylidene chloride (212 ° C), polyvinylidene fluoride (PVDF) (177 ° C), PAR (polyarylate) (250 ° C), PES (polyethersulfone) (225 ° C), high molecular weight acrylic resin, fluorene derivative (140 ° C), crystalline COP (165 ° C) or TAC (triacetyl cellulose) (290 ° C) and other plastic films having a melting point of about 290 ° C or less are preferred, and (meth) acrylic resin, PET, polycycloolefin or polycarbonate are more preferred. The values in parentheses are melting points or glass transition temperatures.

[0123] The total light transmittance of the flexible substrate is preferably 85 to 100%.

[0124] The thickness of the flexible substrate is not particularly limited, but considering its application to a touch panel, it can generally be arbitrarily selected within the range of 25 to 500 μm. When bending the conductive film for the narrow bezel of the touch panel, the thickness of the flexible substrate is more preferably within the range of 25 to 50 μm. In addition, when the flexible substrate also has the function of the touch surface in addition to its own function, it can also be designed with a thickness exceeding 500 μm.

[0125] As one of the preferred embodiments of the flexible substrate, a treated support body that has been subjected to at least one treatment selected from the group consisting of atmospheric pressure plasma treatment, corona discharge treatment, and ultraviolet irradiation treatment can be cited. By performing the above treatment, hydrophilic groups such as OH groups are introduced onto the surface of the treated support body, thereby further improving the adhesion of the metal fine wires.

[0126] Furthermore, as another preferred embodiment of the flexible substrate, it can be a structure having a bottom coating containing a polymer on its surface. By forming the detection portion and the lead-out wiring portion on this bottom coating, the adhesion of the metal fine wires of the detection portion and the lead-out wiring portion to the substrate is further improved.

[0127] The method for forming the bottom coating is not particularly limited. For example, a method of coating a composition for forming a bottom coating containing a polymer on the flexible substrate and performing a heat treatment as needed can be cited. The composition for forming the bottom coating may contain a solvent as needed. The type of the solvent is not particularly limited, and known solvents can be exemplified. And, as the composition for forming the bottom coating containing a polymer, a latex containing polymer fine particles can be used.

[0128] The thickness of the bottom coating is not particularly limited. From the viewpoint of more excellent adhesion of the metal fine wires of the detection portion and the lead-out wiring portion to the substrate, it is preferably 0.02 to 0.3 μm, and more preferably 0.03 to 0.2 μm.

[0129] <Detection portion, lead-out wiring portion>

[0130] The line width of the metal fine wires constituting the detection portion is not particularly limited. From the balance between the conductive characteristics of the metal fine wires and the difficulty of visual recognition, the upper limit is preferably 30 μm or less, more preferably 15 μm or less, further preferably 10 μm or less, particularly preferably 5 μm or less, and most preferably 3 μm or less. The lower limit of the line width is preferably 0.5 μm or more, and more preferably 1.0 μm or more. The line width of the metal fine wires constituting the lead-out wiring portion is not particularly limited. The upper limit is preferably 500 μm or less, more preferably 50 μm or less, further preferably 30 μm or less, particularly preferably 10 μm or less. If within the above range, it is possible to relatively easily form an electrode with low resistance.

[0131] The thickness of the fine metal wire is not particularly limited, and considering the balance between thinning and conductive characteristics, it is preferably 0.01 to 30 μm, more preferably 10 μm or less, further preferably 5 μm or less, particularly preferably 0.01 to 3 μm, and most preferably 0.05 to 2 μm.

[0132] Examples of the material of the fine metal wire include metals or alloys such as gold (Au), silver (Ag), molybdenum (Mo), copper (Cu), titanium (Ti), aluminum (Al), and tungsten (W). Among them, silver or copper is preferred in view of the excellent conductivity of the fine metal wire.

[0133] From the viewpoint of the adhesion between the fine metal wire and the flexible substrate, it is preferred that the fine metal wire contains an adhesive.

[0134] As the adhesive, resin is preferred in view of the better adhesion between the fine metal wire and the flexible substrate. More specifically, examples include (meth)acrylic resins, styrene resins, vinyl resins, polyolefin resins, polyester resins, polyurethane resins, polyamide resins, polycarbonate resins, polydiene resins, epoxy resins, silicone resins, at least one resin selected from the group consisting of cellulose polymers and chitosan polymers, or copolymers composed of monomers constituting these resins.

[0135] The manufacturing method of the fine metal wire is not particularly limited, and known methods can be adopted. For example, there are methods of exposing and developing a photoresist film on a metal foil formed on the surface of a flexible substrate to form a resist pattern, and etching the metal foil exposed from the resist pattern. And there are methods of printing a slurry containing metal particles or metal nanowires on both main surfaces of a flexible substrate and subjecting the slurry to metal plating. And there are methods of pre-forming a patterned groove structure on the surface of a flexible substrate and embedding a slurry containing metal particles or metal nanowires into the groove by screen printing. And there are methods of forming a fine metal wire by pattern printing an ink containing metal particles or metal nanowires on the surface of a flexible substrate using an inkjet method.

[0136] Moreover, in addition to the above methods, there are also methods using silver halide. More specifically, there are the methods described in paragraphs 0056 to 0114 of Japanese Patent Application Laid-Open No. 2014-209332. The method using silver halide will be described in detail later.

[0137] As a preferred mode of the detection unit, there is a mode including a grid pattern composed of silver fine wires. Preferably, a first detection electrode is disposed on the surface of the flexible substrate and a second detection electrode is disposed on the back surface.

[0138] (Other examples of the fine metal wire)

[0139] The first detection electrode 30 and the second detection electrode 32 of the detection unit 20, and the lead wire 23 of the lead wire portion 22 are not limited to being composed of only metal, and can also be composed of a conductive wire containing an adhesive and a metal portion dispersed in the adhesive.

[0140] In the conductive wire, the above-mentioned adhesive contains a first polymer and a second polymer having a glass transition temperature lower than that of the first polymer. In addition, in this specification, the glass transition temperature of a polymer means the glass transition temperature measured by differential scanning calorimetry (DSC). The glass transition temperature is measured using the "Method for Measuring the Transition Temperature of Plastics" specified in JIS K7121 (2012).

[0141] Examples of the first polymer and the second polymer include hydrophobic polymers (hydrophobic resins), etc. More specifically, examples include (meth)acrylic resins, styrene resins, vinyl resins, polyolefin resins, polyester resins, polyurethane resins, polyamide resins, polycarbonate resins, polydiene resins, epoxy resins, silicone resins, at least one resin selected from the group including cellulose polymers and chitosan polymers, or copolymers composed of monomers constituting these resins.

[0142] Moreover, it is preferable that the polymer contains a reactive group that reacts with a crosslinking agent described later.

[0143] As the polymer, it is preferable to have at least one unit selected from the group including the following formulas A, B, C, and D.

[0144] Among them, as the first polymer, from the viewpoint of easily controlling the glass transition temperature to be lower, a polymer composed of one unit selected from the group including the following formulas A, B, C, and D is preferable, a polymer composed of at least one unit selected from the group including B, C, and D is more preferable, and a polymer composed of the unit represented by formula D is further preferable.

[0145] [Chemical formula 4]

[0146]

[0147] R 1 represents a methyl group or a halogen atom, preferably a methyl group, a chlorine atom, or a bromine atom. p represents an integer of 0 to 2, preferably 0 or 1, and more preferably 0.

[0148] R 2 represents a methyl group or an ethyl group, preferably a methyl group.

[0149] R 3represents a hydrogen atom or a methyl group, preferably a hydrogen atom. L represents a divalent linking group, preferably a group represented by the following formula (4).

[0150] Formula (4): -(CO-X 1 )r-X 2 -

[0151] In the formula, X 1 represents an oxygen atom or -NR 30 -. Among them, R 30 represents a hydrogen atom, an alkyl group, an aryl group or an acyl group, and may each have a substituent (for example, a halogen atom, a nitro group, a hydroxyl group, etc.). R 30 is preferably a hydrogen atom, an alkyl group having 1 to 10 carbon atoms (for example, a methyl group, an ethyl group, a n-butyl group, a n-octyl group, etc.), an acyl group (for example, an acetyl group, a benzoyl group, etc.). As X 1 , particularly preferably an oxygen atom or NH-.

[0152] X 2 represents an alkylene group, an arylene group, an alkylene arylene group, an arylene alkylene group or an alkylene arylene alkylene group, and -O-, -S-, -OCO-, -CO-, -COO-, -NH-, -SO 2 -, -N(R 31 )-, -N(R 31 )SO 2 - etc. can be inserted in the middle of these groups. Among them, R 31 represents a straight-chain or branched alkyl group having 1 to 6 carbon atoms, and there are a methyl group, an ethyl group and an isopropyl group, etc. Preferred examples of X 2 include dimethylene, trimethylene, tetramethylene, o-phenylene, m-phenylene, p-phenylene, -CH 2 CH 2 OCOCH 2 CH 2 - and -CH 2 CH 2 OCO(C 6 H 4 )-, etc.

[0153] r represents 0 or 1.

[0154] q represents 0 or 1, preferably 0.

[0155] R 4 represents an alkyl group, an alkenyl group or an alkynyl group having 1 to 80 carbon atoms. As the first polymer, an alkyl group having 1 to 5 carbon atoms is preferred, and as the second polymer, an alkyl group having 5 to 50 carbon atoms is preferred, more preferably an alkyl group having 5 to 30 carbon atoms, and further preferably an alkyl group having 5 to 20 carbon atoms.

[0156] R 5represents a hydrogen atom, a methyl group, an ethyl group, a halogen atom or -CH 2 COOR 6 , preferably a hydrogen atom, a methyl group, a halogen atom or -CH 2 COOR 6 , more preferably a hydrogen atom, a methyl group or -CH 2 COOR 6 , particularly preferably a hydrogen atom.

[0157] R 6 represents a hydrogen atom or an alkyl group having 1 to 80 carbon atoms, which may be the same as or different from R 4 , and the number of carbon atoms of R 6 is preferably 1 to 70, more preferably 1 to 60.

[0158] As other preferred embodiments of the first polymer and the second polymer, from the viewpoint of further preventing water infiltration, a polymer (copolymer) represented by the following formula (5) can be cited.

[0159] Formula (5): -(A)x-(B)y-(C)z-(D)w-

[0160] In addition, in formula (4), A, B, C and D respectively represent the above-mentioned repeating units that have been described.

[0161] In formula (5), x, y, z and w represent the molar ratios of the respective repeating units.

[0162] As x, it is 3 to 60 mol%, preferably 3 to 50 mol%, more preferably 3 to 40 mol%.

[0163] As y, it is 30 to 96 mol%, preferably 35 to 95 mol%, more preferably 40 to 90 mol%.

[0164] As z, it is 0.5 to 25 mol%, preferably 0.5 to 20 mol%, more preferably 1 to 20 mol%.

[0165] As w, it is 0.5 to 40 mol%, preferably 0.5 to 30 mol%.

[0166] In formula (5), particularly preferably, x is 3 to 40 mol%, y is 40 to 90 mol%, z is 0.5 to 20 mol%, and w is 0.5 to 10 mol%.

[0167] As the polymer represented by formula (5), polymers represented by the following formula (6) and formula (7) are preferred.

[0168] [Chemical formula 5]

[0169]

[0170] In formula (6), x, y, z, and w are defined as above.

[0171] [Chemical formula 6]

[0172] Formula (7)

[0173]

[0174] In formula (7), a1, b1, c1, d1, and e1 represent the molar ratios of the respective monomer units. a1 represents 3 to 60 (mol%), b1 represents 30 to 95 (mol%), c1 represents 0.5 to 25 (mol%), d1 represents 0.5 to 40 (mol%), and e1 represents 1 to 10 (mol%).

[0175] The preferred range of a1 is the same as the preferred range of x above, the preferred range of b1 is the same as the preferred range of y above, the preferred range of c1 is the same as the preferred range of z above, and the preferred range of d1 is the same as the preferred range of w above.

[0176] e1 is 1 to 10 mol%, preferably 2 to 9 mol%, and more preferably 2 to 8 mol%.

[0177] The weight-average molecular weight of the polymer represented by formula (5) is preferably 1,000 to 1,000,000, more preferably 2,000 to 750,000, and further preferably 3,000 to 500,000.

[0178] The polymer represented by formula (5) can be synthesized, for example, with reference to Japanese Patent No. 3305459 and Japanese Patent No. 3754745 Gazette, etc.

[0179] In addition, the glass transition temperature of the first polymer and the second polymer is not particularly limited. As the glass transition temperature of the first polymer, it is preferably 0 °C or higher, more preferably 25 °C or higher, and further preferably exceeding 40 °C. As the upper limit, there is no particular limitation, and it is usually preferably 120 °C or lower.

[0180] And, as the glass transition temperature of the second polymer, there is no particular limitation, preferably 40 °C or lower, more preferably 25 °C or lower, further preferably lower than 25 °C, particularly preferably 0 °C or lower, and most preferably lower than 0 °C. As the lower limit, there is no particular limitation, and it is usually preferably -50 °C or higher.

[0181] The difference (absolute value) between the glass transition temperature of the first polymer and the glass transition temperature of the second polymer is not particularly limited, and it is usually preferably 20 to 100 °C.

[0182] The metal part in the conductive wire is the part that ensures the conductive properties of the conductive wire, and the metal part is made of metal. From the viewpoint of more excellent conductive properties, the metal constituting the metal part is preferably at least one metal selected from the group consisting of gold (metallic gold), silver (metallic silver), copper (metallic copper), nickel (metallic nickel), and palladium (metallic palladium).

[0183] In addition, Figure 10 is an enlarged view of the conductive wire 50. Figure 10 shows a state in which the metal part 54 is dispersed in the form of particles in the conductive wire 50. The form of the metal part 54 is not limited to the particle form, and may also be a state in which the metal part 54 is dispersed in the form of a layer (not shown) in the conductive wire 50.

[0184] Figure 10 The conductive wire 50 shown includes an adhesive 52 containing a first polymer and a second polymer, and a plurality of metal parts 54 dispersed in the adhesive 52. As described above, the metal part 54 is in the form of particles.

[0185] The conductive wire may contain materials other than those described above. As materials other than those described above, for example, non-metallic fine particles can be cited. As non-metallic fine particles, for example, resin particles and metal oxide particles can be cited, and metal oxide particles are preferred.

[0186] As metal oxide particles, for example, silica particles and titanium oxide particles can be cited.

[0187] The average particle diameter of the non-metallic fine particles is not particularly limited, and in terms of the spherical equivalent diameter, it is preferably 1 to 1000 nm, more preferably 10 to 500 nm, and further preferably 20 to 200 nm. As long as it is within the above range, the detection part is likely to have more excellent transparency and more excellent conductivity.

[0188] The spherical equivalent diameter of the non-metallic fine particles is a value obtained by calculating the spherical equivalent diameters of any 50 particles using a transmission electron microscope and taking the arithmetic mean of these values.

[0189] <Metal stabilizer>

[0190] Furthermore, for the purpose of stabilizing the metal part, the conductive wire preferably has a metal stabilizer on the surface or inside of the metal part, or in the adhesive. As the metal stabilizer, the following materials can be used alone or simultaneously.

[0191] Antiseptics described in paragraphs 0075 to 0086 of Japanese Patent Application Laid-Open No. 2009-505358.

[0192] Metal ion scavengers described in paragraphs 0077 to 0092 of Japanese Patent Application Laid-Open No. 2009-188360.

[0193] Nitrogen-containing heterocyclic compounds having a mercapto group described in paragraphs 0044 to 0047 of JP-A-2012-146548.

[0194] Compositions for forming a silver ion diffusion inhibiting layer described in paragraphs 0018 to 0049 of JP-A-2013-224397.

[0195] Compounds for forming a silver ion diffusion inhibiting layer described in paragraphs 0030 to 0066 of JP-A-2014-075115.

[0196] Rust preventives described in paragraphs 0050 to 0057 of JP-A-2018-024784.

[0197] Mercaptobenzothiazoles described in paragraphs 0050 to 0057 of JP-A-2019-016488.

[0198] Moreover, as the metal stabilizer, the specific compounds described later can be preferably used.

[0199] As the metal stabilizer, the following compounds or their salts are preferred.

[0200] 2-Mercaptobenzothiazole, 2-mercaptobenzimidazole, 5-mercapto-1-phenyl-1H-tetrazole, 1-(4-carboxyphenyl)-5-mercapto-1H-tetrazole, 3-mercapto-1,2,4-triazole, sodium 1-(m-sulfophenyl)-5-mercapto-1H-tetrazole, 2-mercaptobenzoxazole, 1,2,3-benzotriazole, 1-(3-acetamidophenyl)-5-mercaptotetrazole, 5-amino-2-mercaptobenzimidazole, 6-amino-2-mercaptobenzothiazole, trithiocyanuric acid, 6-(dibutylamino)-1,3,5-triazine-2,4-dithiol, 2-mercaptothiazoline, diethylammonium diethyldithiocarbamate, (2-benzothiazolylthio)acetic acid, 3-(2-benzothiazolylthio)propionic acid, 6-(dibutylamino)-1,3,5-triazine-2,4-dithiol, 2-amino-5-mercapto-1,3,4-thiadiazole, 2-mercapto-5-methylthio-1,3,4-thiadiazole, 2-mercapto-5-ethylthio-1,3,4-thiadiazole, 2,5-dimercapto-1,3,4-thiadiazole, 2-thioacetic acid-5-mercapto-1,3,4-thiadiazole, 2-aminopyrimidine, 5,6-dimethylbenzimidazole, 2-mercaptopyrimidine.

[0201] Among them, as the metal stabilizer, a compound selected from compounds having a mercaptobenzothiazole skeleton or a mercaptothiadiazole skeleton or their salts is particularly effective in improving the sulfur resistance, and thus is most preferred. Specific examples of the most preferred compounds include 2-mercaptobenzothiazole, 5-methyl-2-mercaptobenzothiazole, 2-amino-5-mercapto-1,3,4-thiadiazole, 2-mercapto-5-methylthio-1,3,4-thiadiazole, 2-mercapto-5-ethylthio-1,3,4-thiadiazole, 2,5-dimercapto-1,3,4-thiadiazole and their derivatives or salts.

[0202] The introduction of the metal stabilizer is useful for improving the durability of the metal material in the bent portion and the non-bent portion. Particularly, when silver is used in the metal portion, it is effective in suppressing migration and sulfidation, and thus is preferred. As a method for introducing the metal stabilizer, a method of bringing the conductive film into contact with a solution containing metal stabilizers by coating or impregnation during or after the formation of the conductive wire, or a method of depositing these metal stabilizers on the conductive film by vaporization or the like through a gas-phase reaction can be preferably used. Further, the metal stabilizer is also preferably contained in the aforementioned transparent insulating layer. In particular, by previously containing the metal stabilizer in the transparent insulating layer, contact between the solvent for dissolving the metal stabilizer and the conductive wire can be avoided, and damage to the conductive wire or the adhesive caused by the solvent can be avoided, and thus it is preferred. Therefore, it is preferred that at least one of the first transparent insulating layer and the second transparent insulating layer contains a metal stabilizer.

[0203] There is no limitation on the usage amount of these metal stabilizers. In at least one of the transparent insulating layer and the conductive film, per each conductive layer, it is preferably contained in the range of 1 mg / m 2 ~10 g / m 2 , and more preferably contained in the range of 10 mg / m 2 ~1 g / m 2 .

[0204] The shape of the conductive wire is not particularly limited, and it is preferably linear (such as a straight line, a curve, and a combination thereof, etc.) so as to obtain more excellent detection performance of the touch position when applied to a touch panel. At this time, the line width of the conductive wire is not particularly limited. Considering the balance between the conductive characteristics of the conductive wire and the difficulty of visual recognition, it is preferably 30 μm or less, more preferably 15 μm or less, further preferably 10 μm or less, particularly preferably 5 μm or less, and most preferably 3 μm or less. The lower limit of the line width is preferably 0.5 μm or more, more preferably 1.0 μm or more.

[0205] The thickness of the conductive wire is not particularly limited. Considering the balance between thinning and conductive characteristics, it is preferably 0.01 to 30 μm or less, more preferably 10 μm or less, further preferably 5 μm or less, particularly preferably 0.01 to 3 μm, and most preferably 0.05 to 2 μm.

[0206] At this time, the preferred line width and thickness of the conductive wire represent the width and thickness of the region where the metal exists.

[0207] <Manufacturing method of the detection unit>

[0208] Regarding the manufacturing method of the detection unit, the case where the metal part of the fine metal wire contains silver (metallic silver) will be described as an example. From the viewpoint of obtaining more excellent productivity, a method having the following steps is preferred.

[0209] · Step A:

[0210] A step of simultaneously coating a silver halide-containing coating solution containing at least silver halide and a first polymer and a component adjustment coating solution containing at least a second polymer on a flexible substrate in multiple layers to form a silver halide photosensitive layer.

[0211] · Step B:

[0212] A step of forming a conductive wire containing metallic silver by performing development processing after exposing the silver halide photosensitive layer.

[0213] Hereinafter, each step will be described in detail.

[0214] <Step A>

[0215] Step A is a step of simultaneously coating a silver halide-containing coating solution containing at least silver halide and a first polymer and a component adjustment coating solution containing at least a second polymer on a flexible substrate in multiple layers to form a silver halide photosensitive layer.

[0216] In addition, as the stacking order of the coating solutions during simultaneous multi-layer coating, there is no particular limitation. The silver halide-containing coating solution and the component adjustment coating solution can be stacked in order from the flexible substrate side. Conversely, the component adjustment coating solution and the silver halide-containing coating solution can be stacked in order from the flexible substrate side. The component adjustment coating solution, the silver halide-containing coating solution, and the component adjustment coating solution can also be stacked in order.

[0217] In addition, "coated on the flexible substrate" also includes the case of directly coating on the surface of the flexible substrate and the case of disposing another layer on the flexible substrate and coating on this layer.

[0218] In this process, a silver halide-containing silver halide coating solution and a component adjustment coating solution not containing silver halide are simultaneously coated in multiple layers. Therefore, component diffusion occurs at the interface of the two-layer coating film formed by the two coating solutions. More specifically, a part of the silver halide and the first polymer diffuse from the coating film (hereinafter, also referred to as coating film A) formed by the silver halide-containing coating solution disposed on the flexible substrate into the coating film (hereinafter, also referred to as coating film B) formed by the component adjustment coating solution. As a result, the silver halide and the first polymer are contained in the region on the coating film A side in coating film B, and their contents are less than the contents of the silver halide and the first polymer in coating film A.

[0219] The region on the coating film A side in coating film B (hereinafter, also referred to as "region w".) contains silver halide that has moved from coating film A. Therefore, after the subsequent process B, this region w becomes the upper region in the formed conductive wire. At this time, in the conductive wire, in region w, the content ratio of the second polymer to the total content of the first polymer and the second polymer is likely to be greater than that in the middle region.

[0220] In addition, the silver halide-containing coating solution only needs to contain at least silver halide and the first polymer, and may further contain the second polymer. At this time, the content ratio of the second polymer in the silver halide-containing coating solution to the total content of the first polymer and the second polymer is preferably less than the content ratio of the second polymer in the component adjustment coating solution to the total content of the first polymer and the second polymer.

[0221] And the component adjustment coating solution only needs to contain at least the second polymer, and may further contain silver halide and / or the first polymer. When the component adjustment coating solution further contains silver halide, its content is not particularly limited, and it is preferred that the content of silver halide in the component adjustment coating solution is less than the content of silver halide in the silver halide-containing coating solution. By such treatment, it is easy to obtain a detection portion with less external light reflection.

[0222] When the component adjustment coating solution further contains the first polymer, the content ratio of the first polymer in the component adjustment coating solution to the total content of the first polymer and the second polymer is preferably less than the content ratio of the first polymer in the silver halide-containing coating solution to the total content of the first polymer and the second polymer.

[0223] The silver halide contained in the silver halide coating solution is not particularly limited, and known silver halides can be used. The halogen element contained in the silver halide can be any one of chlorine, bromine, iodine, and fluorine, or these can be combined. For example, silver halides mainly composed of silver chloride, silver bromide, or silver iodide can be preferably used, and silver halides mainly composed of silver bromide or silver chloride can be further preferably used. Chlorobromide silver, iodochlorobromide silver, and iodobromide silver can also be preferably used. Chlorobromide silver, silver bromide, iodochlorobromide silver, or iodobromide silver is more preferably used, and chlorobromide silver or iodochlorobromide silver containing 50 mol% or more of silver chloride is most preferably used.

[0224] In addition, "silver halide mainly composed of silver bromide" herein means a silver halide in which the mole fraction of bromide ions in the silver halide composition is 50% or more. The silver halide particles mainly composed of silver bromide can contain iodide ions and chloride ions in addition to bromide ions.

[0225] The silver halide is in the form of solid particles. The average particle size of the silver halide, in terms of the spherical equivalent diameter, is preferably 0.1 to 1000 nm (1 μm), more preferably 0.1 to 300 nm, and further preferably 1 to 200 nm.

[0226] In addition, the spherical equivalent diameter of the silver halide particles is the diameter of particles having the same volume with a spherical particle shape.

[0227] The shape of the silver halide particles is not particularly limited, and can be various shapes such as spherical, cubic, flat plate (hexagonal flat plate, triangular flat plate, quadrilateral flat plate, etc.), octahedral, and tetradecahedral.

[0228] Regarding the use of metal compounds of Group VIII and Group VIIB such as rhodium compounds and iridium compounds and palladium compounds for stabilizing or highly sensitizing silver halide, reference can be made to the descriptions in paragraphs 0039 to 0042 of Japanese Patent Application Laid-Open No. 2009-188360. Moreover, regarding chemical sensitization, reference can be made to the technical description in paragraph 0043 of Japanese Patent Application Laid-Open No. 2009-188360.

[0229] As described above, the forms of the first polymer contained in the silver halide coating solution and sometimes contained in the component adjustment coating solution and the second polymer contained in the component adjustment coating solution and sometimes contained in the silver halide coating solution are omitted.

[0230] As described below, the silver halide coating solution and the component adjustment coating solution can contain components other than silver halide, the first polymer, and the second polymer, and these components are common in the silver halide coating solution and the component adjustment coating solution.

[0231] The silver halide coating solution and the component adjustment coating solution can further contain gelatin.

[0232] There is no particular limitation on the type of gelatin. For example, in addition to lime-treated gelatin, acid-treated gelatin can be used, and hydrolysates of gelatin, gelatinase-decomposed products, and gelatin modified with amino or carboxyl groups (phthaloylated gelatin, acetylated gelatin) can also be used.

[0233] The silver halide-containing coating solution and the component-adjusting coating solution may further contain a solvent. Examples of the solvent used include water, organic solvents (such as alcohols such as methanol, ketones such as acetone, amides such as formamide, sulfoxides such as dimethyl sulfoxide, esters such as ethyl acetate, ethers, etc.), ionic liquids, and mixed solvents thereof.

[0234] If necessary, other materials in addition to the above materials may be included in the silver halide-containing coating solution and the component-adjusting coating solution. For example, a crosslinking agent for crosslinking the above-mentioned first polymer and second polymer is preferably included. By including the crosslinking agent, the crosslinking between polymers is promoted, and even when the gelatin is decomposed and removed in the subsequent process, the connection between silver metals can be maintained, and as a result, the conductive characteristics are more excellent.

[0235] The method of simultaneously coating the silver halide-containing coating solution and the component-adjusting coating solution in multiple layers is not particularly limited, and a known method can be adopted. For example, a die coating method is preferably used. The die coating method includes a slot coating method, an extrusion coating method, and a curtain coating method. The slot coating method or extrusion coating is preferred, and extrusion coating with high thin-film coating suitability is most preferred.

[0236] In addition, when performing the above-mentioned multi-layer simultaneous coating, from the aspect of easily obtaining the form of the first embodiment of the conductive film for the touch panel, a component-adjusting coating solution containing a second polymer having a composition such that the dry thickness of the film (surface film) formed when coated on a predetermined substrate is 300 nm or more is preferably used.

[0237] Furthermore, after performing the multi-layer simultaneous coating, a drying treatment can be performed on the obtained coating film as needed. By performing the drying treatment, the solvent contained in the coating film obtained from the silver halide-containing coating solution and the coating film obtained from the component-adjusting coating solution can be easily removed.

[0238] Through the above treatment, a photosensitive layer containing silver halide can be formed on the flexible substrate. In addition, in this specification, the above-mentioned "photosensitive layer containing silver halide" is sometimes referred to as "silver halide photosensitive layer" or simply "photosensitive layer".

[0239] <Process B>

[0240] Process B is a process of performing a developing treatment after exposing the silver halide photosensitive layer to form metal fine lines containing silver metal.

[0241] Through this process, silver halide is reduced and a conductive wire containing metallic silver is formed. Additionally, usually, an exposure process is performed in a pattern, and a conductive wire containing metallic silver is formed in the exposed portion. On the other hand, in the non-exposed portion, silver halide is dissolved out by the developing process described below. A non-conductive wire containing the above-mentioned gelatin and the above-mentioned polymer is formed. The non-conductive wire substantially does not contain metallic silver, and the non-conductive wire refers to a region that does not exhibit conductivity.

[0242] Hereinafter, the exposure process and the developing process performed in this process will be described in detail.

[0243] The exposure process is a process of exposing the photosensitive layer. By performing pattern exposure on the photosensitive layer, a latent image is formed from silver halide in the photosensitive layer within the exposed area. In the area where this latent image is formed, a conductive wire is formed by the developing process described below. On the other hand, in the unexposed area where exposure is not performed, silver halide dissolves and flows out from the photosensitive layer during the developing process described below, whereby a transparent film (non-conductive wire) can be obtained.

[0244] The light source used during exposure is not particularly limited, and examples include light such as visible light, ultraviolet light, or radiation such as X-rays.

[0245] The method of performing pattern exposure is not particularly limited. For example, it can be performed by surface exposure using a photomask, or by scanning exposure based on a laser beam. Additionally, the shape of the pattern is not particularly limited and can be appropriately adjusted according to the pattern of the conductive wire to be formed.

[0246] The method of the developing process is not particularly limited. For example, it is possible to use the usual developing process techniques for silver salt films, photographic papers, films for printing plate making, and latex masks for photomasks.

[0247] The type of developer used during the developing process is not particularly limited. For example, it is possible to use PQ (phenidone - hydroquinone) developer, MQ (Metol - hydroquinone) developer, and MAA (Metol - ascorbic acid) developer, etc.

[0248] The developing process can include a fixing process performed for the purpose of stabilizing by removing the silver salt in the unexposed portion. The fixing process can use the fixing process techniques for silver salt films, photographic papers, films for printing plate making, and latex masks for photomasks.

[0249] The fixing temperature in the fixing process is preferably about 20°C to about 50°C, more preferably 25 to 45°C. And the fixing time is preferably 5 seconds to 1 minute, more preferably 7 seconds to 50 seconds.

[0250] The photosensitive layer that has undergone development and fixing processes is preferably subjected to water washing treatment and stabilization treatment.

[0251] Other processes than the above-mentioned Process A and Process B may be included.

[0252] Examples of other processes include:

[0253] Process F, in which the metallic silver of the conductive wires is fused with each other after Process B;

[0254] Process C1, in which the silver halide photosensitive layer is brought into contact with a compound having a metal-adsorbing substituent or a metal-adsorbing structure (hereinafter, also referred to as "specific compound") after Process A and before Process B;

[0255] Process C2, in which the conductive wires are brought into contact with the specific compound after Process B and before Process F;

[0256] Process D, in which the conductive wires are further consolidated after Process B and before Process F;

[0257] Process E, when at least one selected from the group including a silver halide coating solution and a component-adjusting coating solution contains gelatin, the gelatin in the conductive wires is removed after Process B and before Process D; etc.

[0258] In addition, as other processes, an easily adhesive layer forming process described later can also be cited.

[0259] Hereinafter, other processes will be described.

[0260] (Process F)

[0261] Process F is a process in which the metallic silver (contained in the conductive wires) of the conductive wires is fused with each other after Process B. Through this process, the metallic silver is fused with each other, and a detection part having metal fine wires (with more excellent conductivity) can be obtained in its structure.

[0262] As the heating method, there is no particular limitation, and a process of bringing a flexible substrate having conductive wires into contact with superheated steam can be cited.

[0263] There is no particular limitation on the superheated steam, and it may be superheated water steam or a substance in which other gases are mixed with superheated water steam.

[0264] It is preferable to bring the conductive wires into contact with superheated steam within a supply time range of 10 to 300 seconds. If the supply time is 10 seconds or more, the conductivity is greatly improved. And if it is 300 seconds or less, the conductivity is sufficiently improved, so it is more preferable from the economic aspect.

[0265] And, it is preferable that the supply amount is 500 to 600 g / m 3The conductive wire is brought into contact with superheated steam within a range, and the temperature of the superheated steam is preferably controlled to be 100 to 160 °C under 1 atm.

[0266] As other methods of heat treatment, heat treatment at 80 to 150 °C can be cited.

[0267] The heating time is not particularly limited. From the viewpoint of more excellent above effects, it is preferably 0.1 to 5.0 hours, and more preferably 0.5 to 1.0 hours.

[0268] (Process C1)

[0269] Process C1 is a process that is carried out after Process A and before Process B and brings the silver halide photosensitive layer into contact with a specific compound. Through this process, the metallic silver generated in the subsequent Process B is less likely to fuse with each other. In this process, since the specific compound is brought into contact with the silver halide photosensitive layer, there is an effect that the metallic silver is less likely to fuse with each other in a region closer to the surface (interface region) of the silver halide photosensitive layer. Therefore, especially in the conductive wire obtained through the subsequent process, the fusion of the metallic silver with each other in the interface region is more easily hindered. And even in this case, it can be considered that the metallic silver fuses sufficiently with each other in the middle region of the conductive wire, and a detection part with excellent conductivity can be obtained.

[0270] The manufacturing method of the detection part preferably has Process C1 or Process C2 described later, and can also have Process C1 and Process C2.

[0271] As a method of bringing the specific compound into contact with the silver halide photosensitive layer, there is no particular limitation, and generally, a method of bringing a solution in which the specific compound is dissolved and / or dispersed into contact with the silver halide photosensitive layer can be cited. And it can also be a method of bringing a gas containing the specific compound into contact with the silver halide photosensitive layer.

[0272] As a method of bringing a solution containing the specific compound into contact with the silver halide photosensitive layer, there is no particular limitation, and methods such as immersing the silver halide photosensitive layer in the solution and coating the solution on the silver halide photosensitive layer can be cited. More preferably, the method of immersing the silver halide photosensitive layer in the solution. The method of immersing the silver halide photosensitive layer in the solution can be implemented more stably with a simpler device, and moreover, if it is washed after immersion, the remaining solution can be more easily removed, so it is preferred.

[0273] Moreover, the method of bringing the silver halide photosensitive layer into contact with a gas and / or solution containing a compound having a metal adsorbing site also has the following characteristics: on the surface of the silver halide photosensitive layer, the metallic silver is easily adsorbed by the above compound. Thus, on the surface of the conductive wire, the fusion of the metallic silver with each other is more easily hindered.

[0274] A specific compound is a compound having a metal-adsorbing substituent or a metal-adsorbing structure (hereinafter, these are also collectively referred to as "metal-adsorbing sites").

[0275] The metal-adsorbing substituent is not particularly limited. As the metal-adsorbing substituent, at least one selected from the group consisting of a carboxyl group or its salt, a nicotinamide group, an amino group, an imidazole group, a pyrazole group, a thiol group, a thioether group, and a disulfide group is preferred.

[0276] The metal-adsorbing structure is not particularly limited. A nitrogen-containing heterocycle is preferred, a 5- or 6-membered ring azole is more preferred, and a 5-membered ring azole is even more preferred.

[0277] Examples of the nitrogen-containing heterocycle include a tetrazole ring, a triazole ring, an imidazole ring, a thiadiazole ring, an oxadiazole ring, a selenadiazole ring, an oxazole ring, a thiazole ring, a benzoxazole ring, a benzothiazole ring, a benzimidazole ring, a pyrimidine ring, a triazaindene ring, a tetraazaindene ring, a benzindazole ring, a benzotriazole ring, a benzoxazole ring, a benzothiazole ring, a pyridine ring, a quinoline ring, a piperidine ring, a piperazine ring, a quinoxaline ring, a morpholine ring, and a pentazaindene ring, etc.

[0278] These rings may have substituents. Examples of the substituents include a nitro group, a halogen atom (e.g., a chlorine atom and a bromine atom), a cyano group, a substituted or unsubstituted alkyl group (e.g., each of the groups such as a methyl group, an ethyl group, a propyl group, a tert-butyl group, and a cyanoethyl group), an aryl group (e.g., each of the groups such as a phenyl group, a 4-methylsulfonamidophenyl group, a 4-methylphenyl group, a 3,4-dichlorophenyl group, and a naphthyl group), an alkenyl group (e.g., an allyl group), an aralkyl group (e.g., each of the groups such as a benzyl group, a 4-methylbenzyl group, and a phenethyl group), a sulfonyl group (e.g., each of the groups such as a methylsulfonyl group, an ethylsulfonyl group, and a p-toluenesulfonyl group), a carbamoyl group (e.g., each of the groups such as an unsubstituted carbamoyl group, a methylcarbamoyl group, and a phenylcarbamoyl group), a sulfamoyl group (e.g., each of the groups such as an unsubstituted sulfamoyl group, a methylsulfamoyl group, and a phenylsulfamoyl group), a carboxamide group (e.g., each of the groups such as an acetamide group and a benzamide group), a sulfonamide group (e.g., each of the groups such as a methylsulfonamide group, a benzenesulfonamide group, and a p-toluenesulfonamide group), an acyloxy group (e.g., each of the groups such as an acetoxy group and a benzoyloxy group), a sulfonyloxy group (e.g., a methylsulfonyloxy group), a ureido group (e.g., each of the groups such as an unsubstituted ureido group, a methylureido group, an ethylureido group, and a phenylureido group), an acyl group (e.g., each of the groups such as an acetyl group and a benzoyl group), an oxycarbonyl group (e.g., each of the groups such as a methoxycarbonyl group and a phenoxycarbonyl group), and a hydroxyl group, etc. Multiple substituents may be substituted on one ring.

[0279] As the above compound, a compound having a nitrogen-containing 6-membered ring (nitrogen-containing 6-membered ring compound) is preferred. As the nitrogen-containing 6-membered ring compound, a compound having a triazine ring, a pyrimidine ring, a pyridine ring, a pyrroline ring, a piperidine ring, a pyridazine ring or a pyrazine ring is preferred, and a compound having a triazine ring or a pyrimidine ring is more preferred. These nitrogen-containing 6-membered ring compounds may have substituents. Examples of the substituents include an alkyl group having 1 to 6 carbon atoms (preferably 1 to 3 carbon atoms), an alkoxy group having 1 to 6 carbon atoms (preferably 1 to 3 carbon atoms), a hydroxyl group, a carboxyl group, a mercapto group, an alkoxyalkyl group having 1 to 6 carbon atoms (preferably 1 to 3 carbon atoms) and a hydroxyalkyl group having 1 to 6 carbon atoms (preferably 1 to 3 carbon atoms).

[0280] Specific examples of the nitrogen-containing 6-membered ring compound include triazine, methyltriazine, dimethyltriazine, hydroxyethyltriazine, pyrimidine, 4-methylpyrimidine, pyridine and pyrroline.

[0281] The above compound may have one metal adsorption site alone or may have two or more. The above compound preferably has two or more metal adsorption sites.

[0282] (Step C2)

[0283] Step C2 is a step that is carried out after Step B and before Step F and that brings a conductive wire into contact with a specific compound. By this step, metallic silver in the conductive wire (contained in the conductive wire) is less likely to fuse with each other. In this step, since the specific compound is brought into contact with the conductive wire, there is an effect that metallic silver is less likely to fuse with each other in a region closer to the surface (interface region) of the conductive wire. Therefore, in the interface region of the conductive wire, the fusion of metallic silver with each other is more easily hindered. And even in this case, it can be considered that metallic silver fuses sufficiently with each other in the middle region of the conductive wire, and a detection part having excellent conductivity can be obtained.

[0284] In addition, in this step, regarding the method of bringing the conductive wire into contact with the specific compound and the form of the specific compound, etc., they are the same as those in Step C1 already described, and thus the description is omitted.

[0285] (Step D)

[0286] Step D is a step of consolidating the conductive wire after Step B and before the above Step F. By this step, the conductivity of the conductive wire is further improved, and it is easier to improve the adhesion to the flexible substrate of the conductive wire.

[0287] As the method of consolidating the conductive wire, there is no particular limitation. For example, it is preferred to carry out a calendering treatment step in which a flexible substrate having a conductive wire passes between at least a pair of rollers under pressure. Hereinafter, the consolidation treatment using calender rolls is referred to as calendering treatment.

[0288] As the rollers for calendering, plastic rollers and metal rollers can be mentioned. Considering from the aspect of preventing wrinkles, plastic rollers are preferred. The pressure between the rollers is not particularly limited. The pressure between the rollers can be measured using the pressure measurement film "Prescale" (for high pressure) manufactured by Fujifilm Corporation.

[0289] Considering from the aspect that the obtained conductive wire is less visually recognizable, the surface roughness Ra of the roller for calendering is preferably 0 to 2.0 μm, more preferably 0.3 to 1.0 μm.

[0290] The temperature of the consolidation treatment is not particularly limited, preferably 10 °C (without temperature adjustment) to 100 °C. Although it varies depending on the line density, shape, and adhesive type of the pattern of the conductive wire, it is more preferably 10 °C (without temperature adjustment) to 50 °C.

[0291] (Process E)

[0292] When at least one selected from the group including the silver halide coating solution and the component adjustment coating solution contains gelatin, Process E is a process of removing the gelatin (contained in the conductive wire) after Process B and before Process D. By removing the gelatin, as a result, the content of metallic silver in the conductive wire relatively increases, and thus a conductive wire with more excellent conductivity can be obtained.

[0293] Process E can be a process of removing all the gelatin or a process of removing a part of the gelatin. And, in Process E, in addition to the conductive wire, the gelatin can also be removed from the part other than the conductive wire (for example, non-conductive wire) on the flexible substrate.

[0294] As the method for removing gelatin, it is not particularly limited. For example, a method of decomposing and removing with a proteolytic enzyme and a method of decomposing and removing with a specified oxidant can be mentioned.

[0295] In addition, as the method of decomposing and removing gelatin with a proteolytic enzyme, for example, the method described in paragraphs 0084 to 0077 of Japanese Patent Laid-Open No. 2014-209332 can be adopted.

[0296] And, as the method of decomposing and removing gelatin with an oxidant, for example, the method described in paragraphs 0064 to 0066 of Japanese Patent Laid-Open No. 2014-112512 can be adopted.

[0297] (Base coating formation process)

[0298] The undercoat formation step is a step of forming an undercoat on a flexible substrate before step A and obtaining a flexible substrate with an undercoat. As a method for forming the undercoat on the flexible substrate, there is no particular limitation, and examples thereof include a method of coating a composition for forming an undercoat on the flexible substrate. In the undercoat formation step, it is preferable to adjust the formed undercoat so that the absolute value of the difference in refractive index between the undercoat and other adjacent layers (such as the flexible substrate and non-conductive wires) changes less. As a method for adjusting the difference in refractive index between the undercoat and other adjacent layers, there is no particular limitation, and examples thereof include a method of adjusting the types of respective components contained in the compositions for forming each layer.

[0299] As a method for forming the undercoat, there is no particular limitation, and examples thereof include a method of coating a composition for forming an undercoat on a flexible substrate and performing a heat treatment as needed. The composition for forming an undercoat may contain a solvent. The type of the solvent is not particularly limited, and as described above, solvents that can be contained in a silver halide coating solution or the like have been described.

[0300] The thickness of the undercoat is not particularly limited, and from the aspect of further improving the adhesion between the flexible substrate and the silver halide photosensitive layer and the conductive wires, it is preferably 0.02 to 0.3 μm.

[0301] As the undercoat, there is no particular limitation. For example, preferred application examples of the first adhesive layer described in Japanese Patent Application Laid-Open No. 2008-208310 can be preferably used.

[0302] <Other manufacturing methods of the detection unit>

[0303] The manufacturing method of the fine metal wires constituting the detection unit and the lead-out wiring unit is not particularly limited to the above method. For example, plating methods, vapor deposition methods, printing methods, etc. can be appropriately used.

[0304] The formation method of the fine metal wires based on the plating method will be described. For example, the fine metal wires can be composed of a metal plating film formed on a substrate layer by electroless plating on an electroless plating base layer. At this time, after forming a catalyst ink containing at least metal particles in a pattern on the substrate, the substrate is immersed in an electroless plating bath to form a metal plating film. More specifically, the manufacturing method of the metal film substrate described in Japanese Patent Application Laid-Open No. 2014-159620 can be used. In addition, it can also be formed as follows: after forming a resin composition having a functional group capable of interacting with at least a metal catalyst precursor in a pattern on the substrate, a catalyst or a catalyst precursor is imparted, and the substrate is immersed in an electroless plating bath to thereby form a metal plating film. More specifically, the manufacturing method of the metal film substrate described in Japanese Patent Application Laid-Open No. 2012-144761 can be applied.

[0305] Next, a method for forming metal fine lines based on the evaporation method will be described. First, a copper foil layer is formed by evaporation, and copper wirings are formed from the copper foil layer by photolithography, whereby metal fine lines can be formed. Regarding the copper foil layer, in addition to evaporated copper foil, electrolytic copper foil can also be used. More specifically, the process for forming copper wirings described in Japanese Patent Application Laid-Open No. 2014-29614 can be used.

[0306] Next, a method for forming metal fine lines based on the printing method will be described. First, a conductive paste containing conductive powder is coated on a substrate in the same pattern as the metal fine lines, and then a heat treatment is performed, whereby metal fine lines can be formed. For example, pattern formation using the conductive paste is completed by an inkjet method or a screen printing method. As the conductive paste, more specifically, the conductive paste described in Japanese Patent Application Laid-Open No. 2011-28985 can be used.

[0307] <Transparent insulating layer>

[0308] The transparent insulating layer is disposed between the image display module, the conductive film, the polarizing plate, the covering portion, etc. of the touch panel. As the transparent insulating layer, optically transparent adhesives (OCA) and optically transparent resins (OCR) such as UV (Ultra Violet: extreme ultraviolet) curable resins can be used, but are not limited thereto.

[0309] The transparent insulating layer can be disposed on the front and back surfaces of the flexible substrate, covering the areas without the detection portion and the lead wiring portion, as well as on the detection portion and the lead wiring portion. At this time, the transparent insulating layer is transparent and has electrical insulation properties, and also has the function of protecting the detection portion and the lead wiring portion.

[0310] The thickness of the transparent insulating layer is not particularly limited. From the viewpoints of better adhesion and better step difference followability, it is preferably 10 to 200 μm, more preferably 20 to 100 μm.

[0311] As described above, the transparent insulating layer has the property of transmitting light.

[0312] In addition, the total light transmittance of the conductive film including the transparent insulating layer is preferably 85% or more, more preferably 90% or more in the visible light region (wavelength 400 to 700 nm).

[0313] In addition, the above total light transmittance is measured using a spectral colorimeter CM-3600A (manufactured by Konica Minolta, Inc.).

[0314] In addition, the total light transmittance of the transparent insulating layer itself is preferably adjusted so that the conductive film exhibits the above total light transmittance, and is preferably at least 85% or more.

[0315] Various conventionally known additives such as metal stabilizers, leveling agents, surface lubricants, antioxidants, preservatives, light stabilizers, ultraviolet absorbers, polymerization inhibitors, silane coupling agents, inorganic or organic fillers, metal powders, pigments, etc. in the form of powders, particles or foils can be appropriately added to the composition for forming a transparent insulating layer according to the intended use.

[0316] <Protective layer>

[0317] The protective layer contained in the conductive film of the present invention is provided using the photosensitive resin composition described below so as to cover at least a part of the metal fine lines formed on the surface of the transparent flexible substrate. As Figure 4 , Figure 5 shown, in order to suppress disconnection caused by sulfur or halogen in the external environment or iodine eluted from the polarizing plate, it is more preferably provided so as to cover all the lead-out wiring portions. When the lead-out wirings are arranged on both sides of the conductive film, it is preferable that the protective layer is also formed on both sides. The protective layer may further cover a part of the detection electrode extending to the aforementioned passive region.

[0318] 〔Forming process of the protective layer〕

[0319] The method of forming the protective layer using the photosensitive resin composition is not particularly limited. For example, a method of determining the designed thickness of the protective layer, coating the photosensitive resin composition on the substrate, and performing a curing treatment on the coating film as needed to form a cured film (coating method), or a method of forming the protective layer on a temporary substrate and transferring it to the surface of the substrate (transfer method), etc. Among them, from the viewpoint of easy thickness control, the coating method is preferred.

[0320] In the case of the coating method, the method of coating the photosensitive resin composition on the flexible substrate and the lead-out wiring portions is not particularly limited, and known methods (for example, coating methods such as a dispenser, a gravure coater, a comma coater, a bar coater, a knife coater, a die coater or a roll coater, an inkjet method or a screen printing method, etc.) can be used. From the viewpoints of patterning accuracy, film thickness accuracy, and manufacturing efficiency, the screen printing method is preferred.

[0321] The exposure method for the photocuring treatment is not particularly limited. For example, a method of irradiating actinic rays or radiation can be cited. As the irradiation based on actinic rays, light irradiation based on a UV (ultraviolet) lamp and visible light, etc. are used. As the light source, for example, a mercury lamp, a metal halide lamp, a xenon lamp, a chemical lamp, and a carbon arc lamp, etc. can be cited.

[0322] And, as the radiation, electron beams, X-rays, ion beams, far infrared rays, etc. can be cited. By exposing the coating film, the polymerizable groups contained in the compounds in the coating film are activated to cause crosslinking between the compounds, thereby curing the layer. The exposure energy is only required to be 10 - 8000 mJ / cm 2It is sufficient to be about that value, preferably in the range of 50 to 3000 mJ / cm 2 range.

[0323] In order to narrow the border of the touch panel, when bending the lead wiring portion of the conductive film along the edge portion of the display device, the protective layer preferably has flexibility under an outer bending condition of 2 mmφ or less, and more preferably has flexibility of 1 mmφ or less. Also, in order to suppress disconnection of the lead wiring portion, the protective layer preferably has a water permeability of 2000 g / m 2 / day or less, and more preferably has a water permeability of 1000 g / m 2 / day or less. Considering the balance between durability and flexibility, the thickness of the protective layer is preferably 2 times or more of the average particle diameter of the clay mineral contained therein, and preferably 15 μm or less. Moreover, it is preferably 1 μm or more and 10 μm or less, and more preferably 5 μm or more and 8 μm or less. Herein, when the thickness of the protective layer changes, the thickness of the protective layer refers to the thickness of the smallest portion. When the thickness is less than 1 μm, the durability deteriorates significantly, and when it exceeds 15 μm, the flexibility deteriorates and cracks are likely to occur during bending.

[0324] The clay mineral contained in the protective layer is in a particle shape, and its average particle diameter is preferably in the range of 1 / 5 to 1 / 2 of the thickness of the protective layer. When it is less than 1 / 5, the flexibility of the protective layer deteriorates and cracks are likely to occur during bending, and when it exceeds 1 / 2, the durability deteriorates significantly.

[0325] (Photosensitive resin composition)

[0326] <Resin component>

[0327] In the method for manufacturing the conductive film of the present invention, the photosensitive resin composition used in the step of forming the protective layer contains at least one (meth)acrylate monomer represented by formula (1) and formula (2).

[0328] [Chemical formula 7]

[0329]

[0330]

[0331] (In the formula, R 1 , R 2 each represents a (meth)acryloyl group. R 3 represents an unsubstituted or substituted (meth)acryloyl group. X represents a single bond or a divalent linking group represented by the following formula (3).)

[0332] Formula (3): -Y 1 -R 4 -Y 2 -

[0333] (In this formula, R 4 represents an alkylene group having 3 or fewer carbon atoms. Y 1 and Y 2 each represent an oxygen atom or a single bond.)

[0334] As the (meth)acrylate monomer represented by the formula (1) and the formula (2), dicyclopenteny (meth)acrylate, dicyclopentyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, tricyclodecane dimethanol diacrylate, etc. can be used. In order to reduce the water permeability, dicyclopenteny acrylate and tricyclodecane dimethanol diacrylate are more preferred.

[0335] In order to reduce the water permeability, the proportion of the (meth)acrylate monomer in the photosensitive resin composition is preferably 5% by mass or more, more preferably 50% by mass or more, and particularly preferably 70% by mass or more.

[0336] <Other resin components>

[0337] As the resin components other than the aforementioned (meth)acrylate monomer, at least one of an oligomer or a polymer is preferably included to increase the viscosity of the photosensitive resin composition so that it can be applied to coating methods such as the screen printing method described later. As the oligomer and the polymer, an acrylic resin, a methacrylic resin, and an epoxy resin can be used. In order to improve the adhesion to the monomer, an acrylic resin is more preferred.

[0338] As the oligomer, bisphenol A oligomeric epoxy acrylate and bisphenol A diglycidyl ether methacrylic acid adduct can be used. In order to improve the adhesion to the monomer, bisphenol A oligomeric epoxy acrylate is more preferred. In order to improve the durability, the proportion of the oligomer contained in the photosensitive resin composition is preferably 70% by mass or less, more preferably 50% by mass or less, and particularly preferably 30% by mass or less.

[0339] As the polymer, polymethyl methacrylate, polycarbonate, polyethylene terephthalate can be used. In order to improve the adhesion to the monomer, polymethyl methacrylate is more preferred. The proportion of the polymer contained in the photosensitive resin composition is preferably 10% by mass or less, more preferably 5% by mass or less, and particularly preferably 3% by mass or less.

[0340] <Clay mineral>

[0341] The photosensitive resin composition of the present invention contains particulate clay minerals having an average aspect ratio of 2.0 or more. As the clay mineral, talc, kaolinite, montmorillonite, sericite, zeolite, etc. can be used. In order to reduce the water permeability, talc is more preferred.

[0342] In order to reduce the water permeability, the average particle size of the clay mineral is 7.5 μm or less, more preferably less than 2.5 μm. The lower limit of the average particle size is not particularly limited, but since the dispersion property in the resin component deteriorates and wire breakage is caused by sulfur or halogen (especially iodine), it is preferably 1.0 μm or more. Among them, the average particle size uses the D50 value measured and calculated by a particle size distribution meter by the laser diffraction method.

[0343] By reducing the particle size and increasing the aspect ratio, the distance to the metal wiring is increased. Especially in the region where the thickness of the protective layer is small, the clay minerals are easily arranged parallel to the surface direction of the protective layer, and a synergistic effect is produced, which is preferable.

[0344] Moreover, when the clay mineral is used for a protective layer with a thickness of 15 μm or less, in order not to form a moisture channel penetrating in the thickness direction of the protective layer, it is preferable that the proportion of particles with a particle size equal to or greater than the thickness of the protective layer is small, preferably 0.5 vol% or less, more preferably 0.3 vol% or less. Generally, since the clay mineral is a layered compound, the standard deviation of the particle size distribution tends to increase with the reduction of the particle size by pulverization or the like, and it is preferable to perform precise classification operations such as dry / wet sieving, water winnowing, and cyclone separation.

[0345] In order to improve the durability, the proportion of the clay mineral contained in the photosensitive resin composition is preferably 5 mass% to 50 mass%, more preferably 10 mass% to 30 mass%. When it is less than 5 mass%, the effect of bypassing the moisture channel is small, and when it exceeds 50 mass%, the voids of the clay mineral cannot be sufficiently filled with the resin component.

[0346] In order not to form a moisture channel by improving the adhesion with the resin component, the particle surface of the clay mineral is preferably surface-modified with a silane coupling agent containing a functional group capable of crosslinking with the resin component. Examples of the functional group capable of crosslinking include (meth)acryloyl, vinyl, epoxy, styryl, amino, isocyanate, and mercapto groups. For the adhesion with the acrylic resin, (meth)acryloyl is more preferable.

[0347] <Photoinitiator>

[0348] The photosensitive resin composition of the present invention contains a photoinitiator. The type of the photoinitiator is not particularly limited, and known photoinitiators (free radical photoinitiators, cationic photoinitiators) can be used. For example, acetophenone, 2,2 - diethoxyacetophenone, p - dimethylacetophenone, p - dimethylaminopropiophenone, benzophenone, 2 - chlorobenzophenone, benzil, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, 2,2 - dimethoxy - 1,2 - diphenylethane - 1 - one, 1 - cyclohexylphenyl ketone, 1 - hydroxy - cyclohexyl - phenyl ketone, 2 - hydroxy - 2 - methyl - 1 - phenyl - propane - 1 - one, 1 - [4 - (2 - hydroxyethoxy) - phenyl] - 2 - hydroxy - 2 - methyl - 1 - propane - 1 - one, oligo(2 - hydroxy - 2 - methyl - 1 - (4 - (1 - methylvinyl)phenyl)acetone), 2 - hydroxy - 1 - {4 - [4 - (2 - hydroxy - 2 - methyl - propionyl) - benzyl] - phenyl} - 2 - methyl - propane - 1 - one, 2 - methyl - 1 - [4 - (methylthio)phenyl] - 2 - morpholinopropane - 1 - one, 2 - benzyl - 2 - dimethylamino - 1 - (4 - morpholinophenyl) - butanone - 1, bis(2,4,6 - trimethylbenzoyl) - phenylphosphine oxide, 2,4,6 - trimethylbenzoyl - diphenyl - phosphine oxide, bis(2,6 - dimethoxybenzoyl) - 2,4,4 - trimethyl - pentylphosphine oxide, ethyl - (2,4,6 - trimethylbenzoyl)phenylphosphinate, 1,2 - octanedione, 1 - [4 - (phenylthio) -, 2 - (O - benzoyl oxime)], methyl benzoylformate, 4 - methylbenzophenone, 4 - phenylbenzophenone, 2,4,6 - trimethylbenzophenone, 4 - benzoyl - 4'-methyl diphenyl sulfide, 4,4'-bis(dimethylamino)benzophenone, 2,3 - norbornanedione, 1 - [4 - (4 - benzoylphenylthioalkyl)phenyl] - 2 - methyl - 2 - (4 - methylphenylsulfonyl)propane - 1 - one and other carbonyl compounds, and thioxanthone, 2 - chlorothioxanthone, 2 - methylthioxanthone, tetramethylthiuram disulfide and other sulfur compounds, etc. The polymerization initiator can be used alone in one kind, or two or more kinds can be used in combination.

[0349] In the photosensitive resin composition, the content of the photoinitiator is not particularly limited. Considering the curability, the proportion contained in the composition for forming a transparent insulating layer is preferably 0.1 to 10% by mass, more preferably 1 to 5% by mass. In addition, when two or more kinds of polymerization initiators are used, the total content of the polymerization initiators is preferably within the above range.

[0350] In addition to the above, various additives known in the past such as metal stabilizers, leveling agents, surface lubricants, antioxidants, preservatives, light stabilizers, ultraviolet absorbers, polymerization inhibitors, etc. can be appropriately added to the photosensitive resin composition according to the use purpose.

[0351] The basic configuration of the present invention is as above. Above, the conductive film, touch panel, and photosensitive resin composition of the present invention have been described in detail. However, the present invention is not limited to the above embodiments, and various improvements or changes can be made without departing from the gist of the present invention.

[0352] Examples

[0353] Hereinafter, examples are given to further specifically illustrate the features of the present invention. The materials, reagents, amounts thereof and ratios, and operations shown in the following examples can be appropriately changed without departing from the gist of the present invention. Therefore, the scope of the present invention is not limited to the following examples.

[0354] In the first example, photosensitive resin compositions of Examples 1 to 24 and Comparative Examples 1 to 8 were prepared, and the viscosities were measured. Moreover, a conductive film covered with a protective layer was produced using the photosensitive resin composition. For each conductive film with a protective layer, the following durability and flexibility were evaluated. The results are shown in Table 1 below.

[0355] (Evaluation)

[0356] (Measurement of viscosity of photosensitive resin composition)

[0357] Regarding the photosensitive resin composition, an HAAKE MARS II rheometer C35-4 / Ti (diameter: 35 mm, taper: 1°, Gap: 0.052 mm) was used, and the value in mPa·s at a rotation speed of 6 rpm at 20°C was used.

[0358] (Evaluation of durability of conductive film with protective layer)

[0359] 5 μL of a 10% potassium iodide (KI) solution was dropped onto the protective layer directly above the lead wiring of the conductive film with a protective layer obtained by coating / curing the photosensitive resin composition. After natural drying for 1 hour, it was allowed to stand in an environment of 60°C and 90% for 5 days, 10 days, 15 days, and 20 days, and the change rate of the resistance of the KI dropping part before and after each elapsed time was measured.

[0360] For 10 lead wirings on the conductive film, the resistance value between the external connection terminal corresponding to the lead wiring and the end of the detection electrode was measured. The lead wiring that became OL (Over Load) was regarded as having a break, and the evaluation was carried out according to the following criteria.

[0361] (Evaluation criteria)

[0362] AA: No OL (break) after 20 days

[0363] A: There is no OL (open circuit) after 15 days, and there is 1 or more OL (open circuit) after 20 days

[0364] B: There is no OL (open circuit) after 10 days, and there is 1 or more OL (open circuit) after 15 days

[0365] C: There is no OL (open circuit) after 5 days, and there is 1 or more OL (open circuit) after 10 days

[0366] D: There is 1 or more OL (open circuit) after 5 days

[0367] (Evaluation C is the lower limit of the conductive film that can be used as a touch panel.)

[0368] (Flexibility evaluation of the conductive film with a protective layer)

[0369] Using a bending test machine (manufactured by YUASA SYSTEM Co., Ltd., U-shaped expansion and contraction test machine, DLDMLH-FS), the conductive film with a protective layer obtained by coating / curing the photosensitive resin composition was repeatedly subjected to bending tests of φ1.0 mm and φ2.0 mm 10 times, and the cracks in the bent part after the test were observed using a microscope (manufactured by KEYENCE CORPORATION, model: VHX-5000), and the evaluation was carried out. The number of cracks in the protective layer arranged on the outer side (peak fold) of the bend was measured, and the evaluation was carried out according to the following criteria.

[0370] (Evaluation criteria)

[0371] AA: No cracks were observed at φ1.0 mm

[0372] A: 1 - 2 cracks were observed at φ1.0 mm, or no cracks were observed at φ2.0 mm

[0373] B: 1 - 2 cracks were observed at φ2.0 mm

[0374] C: 3 or more cracks were observed at φ2.0 mm

[0375] (Evaluation B is the lower limit for bending and using the conductive film.)

[0376] (Measurement of the particle size of clay minerals)

[0377] The particle size was measured based on volume using a laser diffraction / scattering particle size distribution measuring device (manufactured by HORIBA, Ltd., LA-500). The average particle size used the automatically calculated D50 value. The proportion of particles with a particle size of 7 μm or more was calculated by reading the frequency of the point where the measured cumulative curve intersects the 7 μm line.

[0378] (Measurement of the aspect ratio of clay minerals)

[0379] Regarding the aspect ratio, transmission electron microscope photographs based on the replica method were taken (Titan 80-300 type transmission electron microscope manufactured by FEI Company, acceleration voltage 300 kV, objective aperture 10 mm). The thickness was calculated based on the diameter of a circle (circular equivalent diameter) having an area equal to the projected area of each particle and the length of the replica shadow. Regarding the aspect ratio, the average value of any 100 particles measured was calculated using the following calculation formula.

[0380] Aspect ratio = circular equivalent diameter / thickness

[0381] Hereinafter, Examples 1 to 17 and Comparative Examples 1 to 6 will be described.

[0382] 〔Example 1〕

[0383] <Production of a conductive film with a protective layer>

[0384] (Preparation of silver halide emulsion)

[0385] While stirring, amounts equivalent to 90% of the following Liquids 2 and 3 were added to the following Liquid 1 maintained at 38 °C and pH 4.5 over 20 minutes, thereby forming 0.16-μm core particles. Subsequently, Liquids 4 and 5 were added over 8 minutes, and the remaining 10% of the amounts of Liquids 2 and 3 were added over a further 2 minutes to grow the particles to 0.21 μm. Further, 0.15 g of potassium iodide was added, and the particles were ripened for 5 minutes to complete particle formation.

[0386] Liquid 1:

[0387]

[0388]

[0389] Liquid 2:

[0390] Water 300 ml

[0391] Silver nitrate 150 g

[0392] Liquid 3:

[0393]

[0394] Liquid 4:

[0395] Water 100 ml

[0396] Silver nitrate 50 g

[0397] Liquid 5:

[0398]

[0399] Thereafter, washing with water was carried out by the flocculation method in a conventional manner. Specifically, the temperature was lowered to 35 °C, and sulfuric acid was used to lower the pH until silver halide precipitated (pH within the range of 3.6 ± 0.2). Subsequently, approximately 3 liters of the supernatant was removed (first water washing). After further adding 3 liters of distilled water, sulfuric acid was added until silver halide precipitated. Again, 3 liters of the supernatant was removed (second water washing). The same operation as the second water washing was further repeated once (third water washing), and the water washing / demineralization process was completed. The water-washed / demineralized emulsion was adjusted to pH 6.4 and pAg 7.5, 2.5 g of gelatin, 10 mg of sodium phenylthiosulfonate, 3 mg of sodium phenylthiosulfinate, 15 mg of sodium thiosulfate, and 10 mg of chloroauric acid were added, and chemical sensitization was carried out at 55 °C until the optimal sensitivity was obtained. 100 mg of 1,3,3a,7-tetrazaindene was added as a stabilizer, and 100 mg of PROXEL (trade name, manufactured by ICI Co., Ltd.) was added as a preservative. The finally obtained emulsion was an iodo-chlorobromide silver cube particle emulsion with an average particle size of 0.22 μm and a coefficient of variation of 9%, containing 0.08 mol% of silver iodide and having a ratio of chloro-bromide silver of 70 mol% of silver chloride and 30 mol% of silver bromide.

[0400] (Preparation of the photosensitive layer-forming composition)

[0401] To the above emulsion, 1,3,3a,7-tetrazaindene 1.2×10 -4 mol / mol Ag, hydroquinone 1.2×10 -2 mol / mol Ag, citric acid 3.0×10 -4 mol / mol Ag, sodium 2,4-dichloro-6-hydroxy-1,3,5-triazine 0.90 g / mol Ag, and a trace amount of a hardening agent were added, and the pH of the coating solution was adjusted to 5.6 with citric acid.

[0402] To the above coating solution, a polymer latex containing a polymer represented by the following formula (8) and a dispersant composed of dialkylphenyl PEO sulfate (mass ratio of dispersant / polymer = 2.0 / 100 = 0.02) was added until the ratio to gelatin became polymer / gelatin (mass ratio) = 0.5 / 1.

[0403] As a crosslinking agent, EPOXY RESIN DY 022 (trade name: manufactured by Nagase ChemteX Corporation) was further added. In addition, the addition amount of the crosslinking agent was adjusted so that the amount of the crosslinking agent in the silver halide-containing photosensitive layer described later became 0.09 g / m 2 .

[0404] The photosensitive layer-forming composition was prepared as described above.

[0405] In addition, a polymer represented by the following formula (8) was synthesized with reference to Japanese Patent No. 3305459 and Japanese Patent No. 3754745.

[0406] [Chemical formula 8]

[0407] Formula (8)

[0408]

[0409] (Photosensitive layer forming step)

[0410] The above polymer latex was coated on both sides of a polyethylene terephthalate (PET) film with a thickness of 40 μm, thereby providing an undercoat layer with a thickness of 0.05 μm.

[0411] Next, a silver halide-free layer forming composition mixed with the above polymer latex and gelatin was coated on the undercoat layer, thereby providing a silver halide-free layer with a thickness of 1.0 μm. In addition, the mixing mass ratio of the polymer to gelatin (polymer / gelatin) was 2 / 1, and the content of the polymer was 0.65 g / m 2 .

[0412] Next, the above photosensitive layer forming composition was coated on the silver halide-free layer, thereby providing a silver halide-containing photosensitive layer with a thickness of 2.5 μm. In addition, the mixing mass ratio of the polymer to gelatin (polymer / gelatin) in the silver halide-containing photosensitive layer was 0.5 / 1, and the content of the polymer was 0.22 g / m 2 .

[0413] Next, an overcoat layer forming composition mixed with the above polymer latex and gelatin was coated on the silver halide-containing photosensitive layer, thereby providing an overcoat layer with a thickness of 0.15 μm. In addition, the mixing mass ratio of the polymer to gelatin (polymer / gelatin) was 0.1 / 1, and the content of the polymer was 0.015 g / m 2 .

[0414] (Exposure treatment and development treatment)

[0415] Through a photomask on which a first detection electrode and its lead wiring portion, and a second detection electrode and its lead wiring portion shown in Figure 4 were disposed, each photosensitive layer formed on both sides of the polyethylene terephthalate (PET) film was exposed to parallel light using a high-pressure mercury lamp as a light source.

[0416] The first detection electrode and the second detection electrode, which are formed in a grid shape on each surface of the polyethylene terephthalate film, extend in directions orthogonal to each other on the two surfaces, and the lead wirings led out from the respective detection electrodes are arranged in the peripheral area. After exposure, development is carried out using the following developer, and after further development treatment using a fixing solution (trade name: N3X-R for CN16X, manufactured by Fujifilm Corporation), it is rinsed with pure water and then dried.

[0417] Composition of the developer:

[0418] The following compounds are contained in 1 liter (L) of the developer.

[0419]

[0420] (Heat treatment)

[0421] In addition, it was left standing in a superheated steam bath at 120 °C for 130 seconds for heat treatment.

[0422] (Gelatin decomposition treatment)

[0423] It was further immersed in the following prepared gelatin decomposition solution (40 °C) for 120 seconds, and then immersed in warm water (liquid temperature: 50 °C) for 120 seconds for cleaning.

[0424] Preparation of the gelatin decomposition solution:

[0425] Triethanolamine and sulfuric acid were added to an aqueous solution of a proteolytic enzyme (BIOPRASE 30L, manufactured by Nagase ChemteX Corporation) (concentration of the proteolytic enzyme: 0.5% by mass) to adjust the pH to 8.5.

[0426] (Polymer crosslinking treatment)

[0427] It was further immersed in a 1% aqueous solution of CARBODILITE V-02-L2 (trade name, manufactured by Nisshinbo Co., Ltd.) for 30 seconds, taken out from the aqueous solution, immersed in pure water (room temperature) for 60 seconds, and cleaned.

[0428] Thus, a film A having detection electrodes and lead wiring portions formed on both surfaces of the PET film was obtained.

[0429] The finally obtained first detection electrode is an electrode in which 70 electrode portions are arranged in parallel at intervals of 20 μm within 170 mm × 300 mm, and the second detection electrode is an electrode in which 35 electrode portions are arranged in parallel at intervals of 20 μm within 300 mm × 170 mm. Each electrode portion is composed of Figure 8A grid-like layer of unit square cells with an opening length of 300 μm formed by conductive fine lines. The line width of the conductive fine lines is 4 μm, the thickness of the conductive fine lines is 1.0 μm, and the thickness of the conductive fine line layer is 2.0 μm.

[0430] The lead wirings connected to the respective electrode portions of the first detection electrode and the second detection electrode are integrally formed with the electrode portions. The line width of the lead wirings is 30 μm, the thickness of the lead wirings is 1.0 μm, and the interval between the lead wirings is 30 μm.

[0431] (Production of photosensitive resin composition)

[0432] The designed thickness of the protective layer was determined to be 7.0 μm, and using the materials shown in Table 1, the total amount of the photosensitive resin composition was set to 20 g for production.

[0433] Weighed 10 parts by mass of monomer (M-1), then added 1 part by mass of a photopolymerization initiator and stirred with a magnetic stirrer for 1 hour. After stirring, 79 parts by mass of oligomer (0-1) was added, and defoaming and kneading were performed using a centrifugal planetary mixer (manufactured by THINKY CORPORATION, ARV-310) at 2000 rpm for 3 minutes. After stirring, 10 parts by mass of talc with an average particle diameter of 2.0 μm, an average aspect ratio of 2.3, and a proportion of particles with a particle diameter of 7.0 μm or more of 0% by volume was added, and defoaming was again performed with the centrifugal planetary mixer at 2000 rpm for 3 minutes.

[0434] The kneading machine is not limited to a magnetic stirrer or a centrifugal planetary mixer. A propeller mixer, dissolver, homogenizer, bead mill, roll mill, ultrasonic wave, planetary stirrer, kneader, or extruder can also be used. More specifically, when the viscosity is 3000 mPa·s or more, a planetary stirrer, kneader, roll mill, or extruder is preferred, and when the viscosity is less than 3000 mPa·s, a propeller mixer, dissolver, homogenizer, bead mill, roll mill, or ultrasonic wave is preferred.

[0435] [Table 1]

[0436]

[0437] (Protective layer coating / exposure process)

[0438] The above photosensitive resin composition was coated on the lead wirings by screen printing. Then, exposure was performed by UV exposure (metal halide lamp, 1000 mJ / cm 2 ) under the atmosphere, thereby forming a protective layer (thickness: 7.0 μm) covering the lead wiring portion of the conductive film. The protective layer was formed to completely cover the lead wirings along the peripheral portion of the conductive film and cover the edge portions of the detection electrode portions.

[0439] The durability and flexibility of the produced conductive film with a protective layer were evaluated.

[0440] [Example 2]

[0441] In Example 2, 20 parts by mass of monomer (M-1) and 69 parts by mass of oligomer (O-1) were set, and except for this, a conductive film was produced in the same manner as in Example 1.

[0442] [Example 3]

[0443] In Example 3, 50 parts by mass of monomer (M-1) and 39 parts by mass of oligomer (O-1) were set, and except for this, a conductive film was produced in the same manner as in Example 1.

[0444] [Example 4]

[0445] In Example 4, 70 parts by mass of monomer (M-1) and 19 parts by mass of oligomer (O-1) were set, and except for this, a conductive film was produced in the same manner as in Example 1.

[0446] [Example 5]

[0447] In Example 5, talc with an average particle diameter of 1.4 μm, an average aspect ratio of 2.1, and a proportion of particles with a particle diameter of 7.0 μm or more of 0% by volume was used, and except for this, a conductive film was produced in the same manner as in Example 3.

[0448] [Example 6]

[0449] In Example 6, talc with an average particle diameter of 2.3 μm, an average aspect ratio of 2.6, and a proportion of particles with a particle diameter of 7.0 μm or more of 0.1% by volume was used, and except for this, a conductive film was produced in the same manner as in Example 3.

[0450] [Example 7]

[0451] In Example 7, talc with a protective layer thickness of 9.5 μm, an average particle diameter of 4.0 μm, an average aspect ratio of 2.8, and a proportion of particles with a particle diameter of 9.5 μm or more of 0.3% by volume was used, and except for this, a conductive film was produced in the same manner as in Example 3.

[0452] [Example 8]

[0453] In Example 8, talc with a protective layer thickness of 14.0 μm, an average particle diameter of 7.0 μm, an average aspect ratio of 2.7, and a proportion of particles with a particle diameter of 14.0 μm or more of 0.4% by volume was used, and except for this, a conductive film was produced in the same manner as in Example 3.

[0454] Example 9

[0455] In Example 9, the talc was changed to talc having an average particle diameter of 2.0 μm, an average aspect ratio of 2.4, and a proportion of particles having a particle diameter of 7.0 μm or more of 0.5% by volume. Except for this, a conductive film was produced in the same manner as in Example 3.

[0456] Example 10

[0457] In Example 10, 74 parts by mass of the oligomer (O-1) and 5 parts by mass of talc were set. Except for this, a conductive film was produced in the same manner as in Example 2.

[0458] Example 11

[0459] In Example 11, 59 parts by mass of the oligomer (O-1) and 20 parts by mass of talc were set. Except for this, a conductive film was produced in the same manner as in Example 2.

[0460] Example 12

[0461] In Example 12, 49 parts by mass of the oligomer (O-1) and 30 parts by mass of talc were set. Except for this, a conductive film was produced in the same manner as in Example 2.

[0462] Example 13

[0463] In Example 13, 29 parts by mass of the oligomer (O-1) and 50 parts by mass of talc were set. Except for this, a conductive film was produced in the same manner as in Example 2.

[0464] Example 14

[0465] In Example 14, talc whose surface was surface-modified with a silane coupling agent containing an acryloyl group was set. Except for this, a conductive film was produced in the same manner as in Example 2.

[0466] Example 15

[0467] In Example 15, talc whose surface was surface-modified with a silane coupling agent containing an isocyanate group was set. Except for this, a conductive film was produced in the same manner as in Example 2.

[0468] Example 16

[0469] In Example 16, the thickness of the protective layer was set to 8.0 μm. Except for this, a conductive film was produced in the same manner as in Example 14.

[0470] [Example 17]

[0471] In Example 17, the thickness of the protective layer was set to 6.0 μm, and otherwise, a conductive film was produced in the same manner as in Example 14.

[0472] [Example 18]

[0473] In Example 18, the thickness of the protective layer was set to 5.0 μm, and otherwise, a conductive film was produced in the same manner as in Example 14.

[0474] [Example 19]

[0475] In Example 19, 79 parts by mass of monomer (M-2) was set, no oligomer was added, and 20 parts by mass of talc was set, and otherwise, a conductive film was produced in the same manner as in Example 14.

[0476] [Example 20]

[0477] In Example 20, 78 parts by mass of monomer (M-2) was set and 1 part by mass of polymer (P-1) was set, and otherwise, a conductive film was produced in the same manner as in Example 19.

[0478] [Example 21]

[0479] In Example 21, 76 parts by mass of monomer (M-2) was set and 3 parts by mass of polymer (P-1) was set, and otherwise, a conductive film was produced in the same manner as in Example 19.

[0480] [Example 22]

[0481] In Example 22, 74 parts by mass of monomer (M-2) was set and 5 parts by mass of polymer (P-1) was set, and otherwise, a conductive film was produced in the same manner as in Example 19.

[0482] [Example 23]

[0483] In Example 23, it was changed to talc with a protective layer thickness of 9.5 μm, an average particle size of 4.0 μm, an average aspect ratio of 2.8, a proportion of particles with a particle size of 9.5 μm or more of 0.3% by volume, and the surface was surface-modified with a silane coupling agent containing an acryloyl group, and otherwise, a conductive film was produced in the same manner as in Example 20.

[0484] [Example 24]

[0485] In Example 24, the talc, which was changed to a protective layer with a thickness of 14.0 μm, an average particle size of 7.0 μm, an average aspect ratio of 2.7, a proportion of particles with a particle size of 14.0 μm or more of 0.4% by volume, and the surface of which was surface-modified with a silane coupling agent containing an acryloyl group, was used. Except for this, a conductive film was produced in the same manner as in Example 20.

[0486] 〔Comparative Example 1〕

[0487] In Comparative Example 1, 79 parts by mass of oligomer (O-1) was set and talc was not contained. Except for this, a conductive film was produced in the same manner as in Example 2.

[0488] 〔Comparative Example 2〕

[0489] In Comparative Example 2, the talc was changed to have an average particle size of 1.2 μm, an average aspect ratio of 2.0, and a proportion of particles with a particle size of 7.0 μm or more of 0% by volume. Except for this, a conductive film was produced in the same manner as in Example 2.

[0490] 〔Comparative Example 3〕

[0491] In Comparative Example 3, the talc was changed to have an average particle size of 3.7 μm, an average aspect ratio of 2.5, and a proportion of particles with a particle size of 7.0 μm or more of 0.4% by volume. Except for this, a conductive film was produced in the same manner as in Example 2.

[0492] 〔Comparative Example 4〕

[0493] In Comparative Example 4, the monomer (M-3) was changed. Except for this, a conductive film was produced in the same manner as in Example 2.

[0494] 〔Comparative Example 5〕

[0495] In Comparative Example 5, the talc was changed to have a protective layer thickness of 5.0 μm, an average particle size of 2.4 μm, an average aspect ratio of 2.7, and a proportion of particles with a particle size of 5.0 μm or more of 0.6% by volume. Except for this, a conductive film was produced in the same manner as in Example 3.

[0496] 〔Comparative Example 6〕

[0497] In Comparative Example 6, the talc was changed to have an average particle size of 2.0 μm, an average aspect ratio of 1.5, and a proportion of particles with a particle size of 7 μm or more of 0% by volume. Except for this, a conductive film was produced in the same manner as in Example 2.

[0498] 〔Comparative Example 7〕

[0499] In Comparative Example 7, the thickness of the protective layer was set to 16.0 μm, and otherwise, a conductive film was produced in the same manner as in Example 8.

[0500] [Comparative Example 8]

[0501] In Comparative Example 8, the thickness of the protective layer was set to 16.0 μm, and otherwise, a conductive film was produced in the same manner as in Example 24.

[0502] Table 2 shows the structures and evaluation results of the conductive films of the examples and comparative examples.

[0503]

[0504] From the examples and comparative examples, it can be seen that when using talc with an average particle size less than 1 / 5 or exceeding 1 / 2 of the thickness of the protective layer, talc with a particle size below the thickness of the protective layer and a proportion exceeding 0.5% by volume, or talc with an average aspect ratio less than 2.0, which does not contain the (meth)acrylate monomers represented by Formula (1) and Formula (2), the durability of the conductive film is significantly reduced. Moreover, it can be seen that if the thickness of the protective layer exceeds 15 μm, it will cause an increase in cracks. The increase in cracks will promote the corrosion of the wiring in the bent portion, so it is not preferred.

[0505] It can be seen that within the scope of the present invention, durability and flexibility can be balanced. In particular, when using talc with an average particle size less than 2.5 μm, a protective layer thickness of 8 μm or less, and surface-modified with a silane coupling agent capable of crosslinking with the resin component, durability and flexibility can be balanced at a high level.

[0506] Symbol Explanation

[0507] 10 - Touch panel, 11 - Conductive film, 12 - Image display module, 13 - Controller, 14 - Polarizer, 15 - Covering portion, 16 - Decorative layer, 17a - First transparent insulating layer, 17b - Second transparent insulating layer, 17c - Third transparent insulating layer, 18 - Protective layer, 19 - Flexible circuit board, 20 - Detection portion, 21 - Transparent flexible substrate, 21a - Surface, 21b - Back surface, 22 - Lead-out wiring portion, 23 - Lead-out wiring, 24 - External connection terminal, 25 - Bent portion, 30 - First detection electrode, 31 - Spacing, 32 - Second detection electrode, 33 - Metal fine wire, 34 - Detection electrode, 35 - Opening portion, 50 - Conductive wire, 52 - Adhesive, 54 - Metal portion.

Claims

1. A conductive film having metal fine lines on at least one surface of a transparent flexible substrate, wherein, at least a part of the metal fine lines is covered with a protective layer formed by curing a photosensitive resin composition, the photosensitive resin composition containing a resin-forming component containing at least one (meth)acrylate monomer represented by formula (1) and formula (2), a clay mineral, and a photopolymerization initiator, the thickness (t) of the protective layer is 15 μm or less, the average particle diameter (Dave) of the clay mineral is 1 / 5 to 1 / 2 of the thickness (t) of the protective layer, and the average aspect ratio is 2.0 or more, the proportion of the clay mineral having a particle diameter of the thickness (t) of the protective layer or more is 0.5% by volume or less, the proportion of the clay mineral contained in the photosensitive resin composition is 5 to 50% by mass, [Chemical formula 1] Among them, R 1 and R 2 respectively represent (meth)acryloyl groups, R 3 represents an unsubstituted or substituted (meth)acryloyl group, X represents a single bond or a divalent linking group represented by the following formula (3), Formula (3): -Y 1 -R 4 -Y 2 - Among them, R 4 represents an alkylene group having 3 or less carbon atoms, Y 1 、Y 2 respectively represent an oxygen atom or a single bond.

2. The conductive film according to claim 1, wherein, the average particle diameter (Dave) of the clay mineral is less than 2.5 μm, and the thickness (t) of the protective layer is 8 μm or less.

3. The conductive film according to claim 1 or 2, wherein, the photosensitive resin composition contains 10 to 30% by mass of the clay mineral.

4. The conductive film according to claim 1 or 2, wherein, the clay mineral is talc surface-modified with a silane coupling agent having a functional group capable of crosslinking with the resin-forming component.

5. The conductive film according to claim 4, wherein, the functional group is at least one selected from the group consisting of (meth)acryloyl, vinyl, epoxy, styryl, amino, mercapto, and isocyanate groups.

6. The conductive film according to claim 1 or 2, wherein, the resin-forming component further contains a polymer.

7. The conductive film according to claim 6, wherein, the polymer is (meth)acrylate.

8. A conductive film having metal fine lines on at least one surface of a transparent flexible substrate, wherein, a protective layer containing a resin component having a dicyclopentene structure or a tricyclodecane structure and a clay mineral is laminated on at least a part of the metal fine lines, the thickness (t) of the protective layer is 15 μm or less, the average particle diameter (Dave) of the clay mineral is 1 / 5 to 1 / 2 of the thickness (t) of the protective layer, and the average aspect ratio is 2.0 or more, the proportion of the clay mineral having a particle diameter of the thickness (t) of the protective layer or more is 0.5% by volume or less, and the proportion of the clay mineral contained in the protective layer is 5 to 50% by mass.

9. The conductive film according to claim 8, wherein, the average particle diameter (Dave) of the clay mineral is less than 2.5 μm, the thickness (t) of the protective layer is 8 μm or less.

10. A touch panel having an image display module, the conductive film according to any one of claims 1 to 9, and a covering portion laminated in this order, and the conductive film is disposed on the display surface side of the image display module, wherein, A polarizer is also disposed on at least one of the interfaces between the image display module and the conductive film and between the conductive film and the covering portion.

11. The touch panel according to claim 10, which has a lead wiring portion including the metal fine wires, At least a part of the lead wiring portion is bent along the edge portion of the image display module.

12. A photosensitive resin composition, comprising: A resin forming component containing at least one (meth)acrylate monomer represented by formula (1) and formula (2); A clay mineral having an average particle diameter (Dave) of 7.5 μm or less and an average aspect ratio of 2.0 or more, and surface-modified with a silane coupling agent having a functional group capable of crosslinking with the resin forming component; and A photopolymerization initiator, The viscosity of the photosensitive resin composition is 5000 mPa·s or more, The proportion of the clay mineral contained in the photosensitive resin composition is 5 to 50% by mass, [Chemical formula 2] Wherein, R 1 、R 2 respectively represent (meth)acryloyl, R 3 represents an unsubstituted or substituted (meth)acryloyl group, X represents a single bond or a divalent linking group represented by the following formula (3), Formula (3): -Y 1 -R 4 -Y 2 - wherein, R 4 represents an alkylene group having 3 or less carbon atoms, Y 1 and Y 2 each represent an oxygen atom or a single bond, respectively.

13. The photosensitive resin composition according to claim 12, Wherein, The average particle diameter (Dave) of the clay mineral is less than 2.5 μm.

14. A method for manufacturing a conductive film, which Comprises: A step of forming metal fine wires on at least one surface of a transparent flexible substrate; A step of determining the designed thickness of the protective layer to cover at least a part of the metal fine wires and be 15 μm or less; A step of applying the photosensitive resin composition to at least a part of the metal fine wires, the photosensitive resin composition containing: a resin forming component containing at least one (meth)acrylate monomer represented by formula (1) and formula (2), a photopolymerization initiator, and a clay mineral having an average particle diameter (Dave) of 1 / 5 to 1 / 2 of the designed thickness, a proportion of particles having a particle diameter of the designed thickness or more of 0.5% by volume or less, and an average aspect ratio of 2.0 or more; and A step of forming a protective layer having the same thickness as the designed thickness by curing the photosensitive resin composition applied to at least a part of the metal fine wires; The proportion of the clay mineral contained in the photosensitive resin composition is 5 to 50% by mass, The viscosity of the photosensitive resin composition is 5000 mPa·s or more, [Chemical formula 3] Among them, R 1 and R 2 each represent (meth)acryloyl, R 3 represents an unsubstituted or substituted (meth)acryloyl group, X represents a single bond or a divalent linking group represented by the following formula (3), Formula (3): -Y 1 -R 4 -Y 2 - wherein, R 4 represents an alkylene group having 3 or less carbon atoms, Y 1 and Y 2 represent an oxygen atom or a single bond, respectively.

15. The method for manufacturing a conductive film according to claim 14, Wherein, The average particle diameter (Dave) of the clay mineral is less than 2.5 μm, The designed thickness of the protective layer is 8 μm or less.

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