JP6080209B2 - Flexible electrode sheet - Google Patents

Description

  The present invention relates to an electrode sheet having flexibility. Specifically, the present invention relates to an electrode sheet that can be sufficiently bent in one direction and can be used for a flat panel display such as a touch panel, a liquid crystal display, a plasma display, and an organic EL display, a lighting device, a solar cell, and the like.

  The touch panels currently in practical use are almost limited to flat panels having a flat touch surface. However, in a three-dimensional image display device, an in-vehicle electronic device, a game device, and the like, a touch panel having a curved touch surface is desired to improve the operability of the device. For example, Patent Document 1 discloses a device in which a capacitive touch panel is arranged on the outermost surface side of an image display device having a cylindrical display screen. Since the cylindrical display screen of the image display device can be seen through the touch surface of the capacitive touch member, the image display device can be intuitively operated by touching the touch surface while viewing the image.

  Usually, in a touch panel, a plurality of transparent electrodes made of ITO (indium tin oxide) are used. Although this transparent electrode made of ITO has good characteristics as transparency and conductivity, it is weak against mechanical loads such as bending, and has defects such as cracking and a significant increase in electrical resistance. .

  Therefore, as a transparent conductive material constituting the transparent electrode of the touch panel, a conductive polymer (for example, Patent Document 2) or a carbon nanotube (for example, Patent Document 3) is used instead of an oxide-based transparent conductive material such as ITO. Proposals have also been made.

JP 2010-244772 A JP 2008-47026 A WO2006 / 030981

  Around the region where the plurality of transparent electrodes 110 and 120 of the touch panel 101 are formed, as shown in FIGS. 16 and 17, a plurality of routings electrically connected to each of the plurality of transparent electrodes 110 and 120 are provided. A wiring 125 exists. The routing wiring 125 must be a material having higher conductivity than the transparent conductive material of the transparent electrodes 110 and 120, and a conductive material having flexibility such as the above-described conductive polymer and carbon nanotube is not suitable. . Usually, a metal paste, which is a low resistance material, is often used for the routing wiring 125, but these are weak against mechanical loads such as bending, and if the touch panel is bent, a crack 300 is generated or electric resistance is increased. The size is greatly increased (see FIG. 18). That is, even if the transparent electrodes 110 and 120 are formed using the above-described transparent conductive material having flexibility, a touch panel having a curved touch surface has not been practically used.

  In addition, the structure (henceforth an "electrode sheet") provided with the some transparent electrode 110,120 and the routing wiring 125 on the base film 104 is used also for purposes other than a touch panel use. For example, it is also used for various optical devices such as flat panel displays such as liquid crystal displays, plasma displays, and organic EL displays, illumination devices, and solar cells, and these also have the same problem regarding flexibility.

  Accordingly, an object of the present invention is to solve the above-mentioned problem, and to provide a flexible electrode sheet that can be sufficiently bent in one direction even with a lead wiring formed of a metal paste. It is in.

  In order to achieve the above object, the present invention is configured as follows.

  According to the first aspect of the present invention, a base film having flexibility, a plurality of transparent electrodes formed of a transparent conductive material having flexibility on the first surface of the base film, and the plurality And a plurality of routing wires electrically connected to each of the plurality of transparent electrodes, and a first of the routing wires is formed around the region where the transparent electrodes are formed. Provided is an electrode sheet having flexibility, in which a portion formed along a direction is formed in close contact with a corrugated surface that repeats a mountain and valley extending along a second direction intersecting the first direction. .

  According to the second aspect of the present invention, the electrode having flexibility according to the first aspect, wherein the height difference D between the peaks and valleys of the wavy surface is 0.1 to 100 μm and the width W of the peaks is 0.1 to 5 mm. Provide a sheet.

  According to the 3rd aspect of this invention, the said wavy surface is the 1st surface of the said base film, and the some strip | belt-shaped convex part arrange | positioned mutually parallel along a 2nd direction on the 1st surface. The electrode sheet which has the flexibility of the 1st aspect or the 2nd aspect comprised by these is provided.

  According to a fourth aspect of the present invention, there is provided the electrode sheet having flexibility according to the third aspect, wherein the material of the belt-like convex portion is a photosensitive resin having electrical insulation.

  According to the 5th aspect of this invention, the said corrugated surface is comprised by the uneven | corrugated | grooved part formed in the 1st surface of the said base film, The flexibility of either the 1st aspect or the 2nd aspect An electrode sheet is provided.

  According to the sixth aspect of the present invention, there is provided the electrode sheet having flexibility according to the fifth aspect, wherein the material of the uneven portion is a photosensitive resin having electrical insulation.

  According to a seventh aspect of the present invention, there is provided the flexible electrode sheet according to any one of the first to sixth aspects, wherein the metal material of the metal paste of the routing wiring is silver, copper, aluminum, or nickel. To do.

  According to an eighth aspect of the present invention, there is provided the flexible electrode sheet according to any one of the first to seventh aspects, wherein the routing wiring has a thickness of 0.1 to 50 μm.

  According to the ninth aspect of the present invention, the plurality of transparent electrodes are arranged in parallel with each other along the second direction, and the plurality of first electrodes arranged in parallel with each other along the first direction, An electrode sheet having flexibility according to any one of the first to eighth aspects, comprising: a plurality of second electrodes insulated from the plurality of first electrodes; and forming an electrode structure of a capacitive touch panel. provide.

  According to the electrode sheet of the present invention, the portion formed along the first direction of the routing wiring has a wavy surface that repeats the peaks and valleys extending along the second direction intersecting the first direction. Since the electrode sheet is curved so as to increase the distance between the ridges of the corrugated surface, the routing wiring fixed along the corrugated surface and its surface is more gradual. Deform to wave shape. This wave-shaped deformation can absorb the stress caused by the curvature of the electrode sheet, so that it is a lead wiring formed of metal paste and does not crack or increase the electrical resistance significantly. .

The perspective view which shows one Example of the electrode sheet concerning this invention AA line sectional view on the lead wiring at the time of non-deformation of the electrode sheet shown in FIG. BB sectional drawing on the electrode structure at the time of the non-deformation of the electrode sheet shown in FIG. Schematic sectional view showing the detection principle of the mutual capacitive touch panel mentioned as an example of the electrode sheet AA line sectional view on the lead wiring at the time of deformation of the electrode sheet shown in FIG. The figure which showed an example of the process of forming a wavy surface Plan view of a mask used in the exposure process of FIG. The perspective view which shows another Example of the electrode sheet concerning this invention FIG. 8 is a cross-sectional view taken along line AA on the lead wiring when the electrode sheet shown in FIG. 8 is not deformed. AA line sectional view on the lead wiring at the time of deformation of the electrode sheet shown in FIG. The figure which showed another example of the process of forming a wavy surface Plan view of the mask used in the exposure process of FIG. The figure which showed another example of the process of forming a wavy surface The figure which showed another example of the process of forming a wavy surface The figure which showed another example of the process of forming a wavy surface The perspective view which shows one Example of the electrode sheet concerning a prior art FIG. 16 is a cross-sectional view taken along line AA on the lead wiring when the electrode sheet shown in FIG. 16 is not deformed. AA line sectional view on the lead wiring at the time of deformation of the electrode sheet shown in FIG.

  Embodiments according to the present invention will be described below in detail with reference to the drawings.

[First Embodiment]
(Configuration of electrode sheet)
First, the configuration of the electrode sheet according to the present embodiment will be described taking an example of a mutual capacitive touch panel application. FIG. 1 is a perspective view showing an embodiment of an electrode sheet according to the present invention, FIG. 2 is a cross-sectional view taken along line AA on the lead wiring when the electrode sheet shown in FIG. 1 is not deformed, and FIG. It is a BB sectional view on an electrode structure at the time of non-deformation of an electrode sheet shown in Drawing 1.

  As shown in FIGS. 1 to 3, the electrode sheet 1 includes a base film 4, an electrode structure 9 of a mutual capacitive touch panel formed on the first surface of the base film 4, and an electrode structure 9. A plurality of routing lines 25 formed around the formed region, and a portion of the routing lines 25 formed along the X direction extends along the Y direction intersecting (orthogonal) with the X direction. It is formed in close contact with the corrugated surface 26 that repeats the extending valleys.

  The base film 4 is a flat resin film with both sides having flexibility, for example, a PET (polyethylene terephthalate) film, a PC (polycardate) film, a COP (cycloolefin polymer) film, a PVC (polyvinyl chloride). ) Film, COC (cycloolefin copolymer) film or the like. In particular, the COP film is preferable because it not only has excellent optical isotropy, but also has excellent dimensional stability and, in turn, processing accuracy. The thickness is generally 20 μm to 0.5 mm.

  The electrode structure 9 of the mutual capacitance type touch panel shown in FIGS. 1 and 3 includes a plurality of X electrodes 10 arranged in parallel with each other along the X direction, and is positioned above and parallel to each other along the Y direction. And a plurality of X electrodes 10 and a plurality of insulated Y electrodes 20. 1 and 3, the X electrode 10 and the Y electrode 20 are located on the front surface of the base film 4.

  As shown in the schematic diagram of FIG. 4, the X electrode 10 located below functions as an electrode on the transmission side, and the Y electrode 20 located above functions as an electrode on the reception side. When the object 200 such as a finger is not in contact with or close to the Y electrode 20 side, that is, the touch surface side, an electric field in which the electric lines of force L are directed from the X electrode 10 on the transmission side to the Y electrode 20 on the reception side. Is formed. When the object 200 such as a finger approaches the Y electrode 20 to such an extent as to affect the electric field, a part of the electric force line L goes around the Y electrode 20 and is absorbed by the object such as the finger. As a result, a change occurs in the mutual capacitance, and the coordinate where the change has occurred can be detected as a detection point. In order to eliminate the influence of noise from the LCD, the width of the X electrode 10 is set wider than that of the Y electrode 20, and conversely, the gap between the X electrodes 10 is set narrower than the gap between the Y electrodes 20. ing.

  The X electrode 10 and the Y electrode 20 are made of a transparent conductive material having flexibility. Examples of the transparent conductive material include a material composed of a photocurable resin binder and conductive nanofibers. Examples of conductive nanofibers include metal nanowires prepared by continuously applying an applied voltage or current from the tip of a probe to the surface of a precursor carrying metal ions such as gold, silver, platinum, copper, and palladium. And peptide nanofibers obtained by adding gold particles to nanofibers formed by self-organization of peptides or derivatives thereof. Even black conductive nanofibers such as carbon nanotubes can be used if there is a difference in shadow color or reflectivity. Examples of the photocurable resin binder include urethane acrylate and cyanoacrylate. Moreover, it can form with conductive polymers, such as PEDOT (polyethylene dioxythiophene), as a transparent conductive material.

  As a method of forming the X electrode 10 on the base film 4, a known technique can be used. For example, it can be formed by a printing method such as a screen printing method, a gravure printing method, and an ink jet printing method using the ink made of the transparent conductive material.

  Further, after forming the transparent conductive film by a coating method such as dip coating, spin coating, roll coating or spray coating, unnecessary portions may be removed by etching or the like. Further, even if a photosensitive conductive film (dry film resist) formed by laminating a conductive layer and a photosensitive resin layer having adhesiveness on the support film 111 is used, an electrode pattern is formed by exposure and development. Good.

  On the other hand, as a method of forming the Y electrode 20 on the base film 4 and the X electrode 10 </ b> X, it can be formed by various printing methods in the same manner as the X electrode 10. Further, the Y electrode 20 may be formed by using a photosensitive conductive film (dry film resist) in the same manner as the X electrode 10 and exposing and developing.

  The X electrode 10 and the Y electrode 20 are insulated by the insulating film 3 arranged in the same shape as the Y electrode 20 so as to support the Y electrode 20 therebetween (see FIGS. 1 and 3).

  As a material constituting the insulating film 3, it is preferable to use a resin obtained by imparting photocurability to a heat-sensitive adhesive or pressure-sensitive adhesive resin. For example, acrylic resin, styrene resin, epoxy resin, amide resin, amide epoxy resin, alkyd resin, phenol resin, ester resin, urethane resin, epoxy acrylate resin obtained by reaction of epoxy resin with (meth) acrylic acid, epoxy acrylate resin And an acid-modified epoxy acrylate resin obtained by the reaction of acid anhydride.

  As shown in FIG. 1, the routing wiring 25 performs a role of transmitting an electrical signal between the X electrode 10 and the Y electrode 20 and a control unit (not shown), and the electrode structure 9 is formed. It is disposed around the area, that is, around the base film 4. One end of the routing wiring 25 is connected to the end portions of the first X electrode 10 and the Y electrode 20, and the other end is connected to a connection terminal (not shown) for connecting to a flexible circuit (FPC) or the like. doing.

  Since the lead wiring 25 is formed outside the display area, it does not need transparency, but it needs to be formed from a material having a small resistance value. Therefore, a material having higher conductivity than the transparent conductive material of the X electrode 10 and the Y electrode 20 is preferably used as the material of the routing wiring 25. Specifically, it is made of a paste-like conductive material made of a metal material and a resin material.

  Examples of the metal material used for the lead wiring 25 include gold, silver, copper, aluminum, nickel, chromium, platinum, or an alloy containing any one or more of these metals, such as APC. (Silver, palladium, copper alloy), MAM (molybdenum, aluminum, molybdenum alloy) and the like.

  Examples of the resin material used for the routing wiring 25 include phenol resin, epoxy resin, unsaturated polyester, vinyl ester resin, diallyl phthalate resin, oligoester acrylate resin, xylene resin, bismaleide triazine resin, furan. Examples thereof include resins, urea resins, polyurethanes, melamine resins, silicon resins, acrylic resins, oxetane resins, oxazine resins, polyamides, polyimides, acrylic resins, ketone resins, polystyrenes, polyesters, and the like.

  Examples of the method for forming the lead wiring 25 in the present invention include a printing method such as screen printing, offset printing, gravure printing, flexographic printing, and ink jet printing, or a brush coating method. Further, when a thinner circuit is formed as the lead wiring 25, a dispenser can be used.

  The thickness of the routing wiring 25 is preferably 0.1 to 50 μm. When the thickness of the routing wiring 25 is smaller than 0.1 μm, the resistance value becomes high and the touch panel performance cannot be sufficiently obtained. Further, when the thickness of the routing wiring 25 is larger than 50 μm, the height difference between the mountains and valleys is filled. Flexibility cannot be obtained.

  A portion of the routing wiring 25 formed along the X direction is formed in close contact with the corrugated surface 26 that repeats the peaks and valleys extending along the Y direction (see FIGS. 1 and 2). In the first embodiment, the corrugated surface 26 is constituted by the first surface of the base film 4 and a plurality of strip-shaped convex portions 27 arranged parallel to each other along the direction Y on the first surface. Has been.

  The material of the belt-like convex portion 27 is a photosensitive resin having the same electrical insulation as that of the insulating film 3 described above, that is, a resin obtained by imparting photocurability to a heat-sensitive adhesive or pressure-sensitive adhesive resin. For example, acrylic resin, styrene resin, epoxy resin, amide resin, amide epoxy resin, alkyd resin, phenol resin, ester resin, urethane resin, epoxy acrylate resin obtained by reaction of epoxy resin with (meth) acrylic acid, epoxy acrylate resin And an acid-modified epoxy acrylate resin obtained by the reaction of acid anhydride.

  2 has a trapezoidal cross-sectional shape and includes a sloped side surface 27b sharing a long side with a flat peak surface 27a. The sloped side surface 27b has a slope in which the cross-sectional width of the belt-like convex portion 27 gradually increases from the upper side to the lower side of the sloped side surface 27b. Further, the flat surface of the base film 4 is exposed in the gap between the belt-like convex portions 27.

  As described above, the portion of the routing wiring 25 formed along the X direction is formed in close contact with the corrugated surface 26 that repeats the peaks and valleys extending along the Y direction. When curved so as to increase the distance between the peaks of the surface 26, the wavy surface 26 and the routing wiring 25 fixed along the surface thereof are deformed so as to have a gentler wave shape (see FIG. 5). ). At this time, the distance between the peaks of the routing wiring 25 has a wide wave shape, but the length of the routing wiring 25 itself does not change. Since the stress generated by the curvature of the electrode sheet 1 can be absorbed by such a wave-shaped deformation, the lead wiring 25 formed of a metal paste is cracked or the electric resistance is greatly increased. There is nothing to do.

  The wavy surface 26 is preferably a wave having a peak-to-valley height difference D of 0.1 to 100 μm and a peak width W of 0.1 to 5 mm. When the height difference D between the peaks and valleys is smaller than 0.1 μm, the stress absorption effect of the belt-like convex portion 27 when the electrode sheet 1 is curved cannot be sufficiently obtained. Further, if the height difference D between the peaks and valleys is larger than 100 μm, it is difficult to form the wiring 25 along the wavy surface 26. On the other hand, if the width W of the mountain is smaller than 0.1 mm, it is difficult to form the wiring 25 along the wavy surface 26. On the other hand, if the width W of the ridge is larger than 5 mm, the stress absorbing effect of the belt-like convex portion 27 when the electrode sheet 1 is curved cannot be sufficiently obtained.

  Further, the sloped side surface 27b of the belt-like convex portion 27 is formed so that the cross section thereof is a straight line in the example shown in FIG. The sloped side surface 27b can be formed in a convex shape or a concave shape in addition to being formed so that the cross section is linear.

(Method of forming a wavy surface)
Next, a method for forming the wavy surface of the present embodiment will be described with reference to the drawings.

  FIG. 6 is a diagram illustrating an example of a process of forming a waved surface. Specifically, the electrode structure 9 of the mutual capacitive touch panel is formed by using the dry film resist 14 including the support film 101 and the photosensitive resin layer 13 having adhesiveness laminated on the support film 11. A step of laminating the photosensitive resin layer 13 so that the photosensitive resin layer 13 is in close contact with the surface of the base film 4 on the electrode structure 9 side (see FIG. 6A), and a predetermined step of the photosensitive resin layer 13 on the base film 4 An exposure step (see FIG. 6B) for irradiating a portion with the actinic ray L2 and a development step for forming a wavy surface by developing the exposed photosensitive resin layer 13 (FIG. 6C). reference).

  The support film 11 is a plastic film having a surface subjected to a release treatment. Examples of the plastic film include a polytetrafluoroethylene film, a polyethylene terephthalate film, a polyethylene film, a polypropylene film, a polymethylpentene film, and a polyimide film. Among these, a biaxially stretched polyethylene terephthalate film excellent in dimensional stability is particularly preferable. The biaxially stretched polyethylene terephthalate film subjected to the mold release treatment is commercially available, and they can be used. The release treatment may be a non-silicone release treatment surface as well as a silicone release treatment surface.

  In the laminating step, for example, the dry film resist 14 is laminated by pressing the photosensitive resin layer 13 side onto the base film 4 and the electrode structure 9 while heating after removing the protective film, if any. It is done by the method to do. In addition, it is preferable to laminate | stack this operation under pressure reduction from the viewpoint of adhesiveness and followable | trackability.

  As an exposure method in the exposure step, a mask exposure method is exemplified. As the light source of the actinic ray L2, a known light source such as a carbon arc lamp, a mercury vapor arc lamp, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a xenon lamp, or the like that effectively radiates ultraviolet rays, visible light, or the like is used. Also, an Ar ion laser, a semiconductor laser, or the like that effectively emits ultraviolet light, visible light, or the like is used. Further, those that effectively radiate visible light, such as photographic flood bulbs and solar lamps, are also used.

  The shape of the mask 5 used for exposure is a light-shielding portion 5d that covers a plurality of light-transmitting portions 5a cut out corresponding to the peak surface 27a of the above-described band-shaped convex portion 27 and a portion where the above-described band-shaped convex portion 27 is not formed. And a gradation portion 5b that covers the portion corresponding to the sloped side surface 27b and gradually changes the exposure amount (see FIG. 7). In FIG. 1, the corrugated surface 26 is formed in an L-shaped region, but the mask in FIG. 7 is described as a rectangular region for convenience.

  By using the mask 5 as described above, the exposure amount of the uncured photosensitive resin layer 13 is controlled for each portion. That is, the portion of the photosensitive resin layer 13 covered with the light transmitting portion 5a of the mask 5 is cured, and the portion of the photosensitive resin layer 13 covered with the light shielding portion 5d of the mask 5 is left uncured. Then, the portion of the photosensitive resin layer 13 covered with the gradation portion 5b is semi-cured so that the degree of curing gradually decreases as the distance from the light transmitting portion 5a increases.

  Alternatively, a method of irradiating the active light beam L2 by a direct drawing method using a laser exposure method or the like may be employed as in the mask exposure method.

  When the support film 11 is transparent to the actinic light, the actinic light L2 can be irradiated through the support film 11, and when the support film 11 is light-shielding, the support film 11 is exposed to light after being removed. The active resin layer 13 is irradiated with active light L2.

  Moreover, when the electrode structure 9 and the base film 4 are transparent to the active light, the active light L2 can be irradiated to the photosensitive resin layer 13 through the base film 4 from the base film 4 side. From the viewpoint of resolution, it is preferable to irradiate the photosensitive resin layer 13 with the actinic ray L2 from the side opposite to the base film 4.

  In the developing process of this embodiment, the photosensitive resin layer 13 is removed in inverse proportion to the exposure amount. Specifically, when the transparent support film 11 is present on the photosensitive resin layer 13, the support film 11 is first removed, and then the photosensitive resin layer 13 is inversely proportional to the exposure amount by wet development. To remove. As a result, the portion of the photosensitive resin layer 13 that has been covered with the light-transmitting portion 5 a of the mask 5 remains as it is, and the peak surface 27 a of the belt-like convex portion 27 is formed. Further, the uncured portion covered with the light shielding portion 5d of the mask 5 is all removed, and the belt-like convex portion 27 is not formed.

  And the semi-hardened part covered with the gradation part 5b remains according to the hardening degree, and the side surface 27b with the gradient of the strip | belt-shaped convex part 27 is formed. The semi-cured portion is deformed so as to be crushed at the time of development, thereby changing from a change in the horizontal direction to a change in the vertical (thickness) direction.

  The wet development is performed by a known method such as spraying, rocking immersion, brushing, or scraping, using a developer corresponding to a photosensitive resin such as an alkaline aqueous solution, an aqueous developer, or an organic solvent developer. .

  As the developing solution, a safe and stable solution having good operability such as an alkaline aqueous solution is used. Examples of the base of the alkaline aqueous solution include alkali hydroxides such as lithium, sodium, or potassium hydroxide, alkali carbonates such as lithium, sodium, potassium, or ammonium carbonate or bicarbonate, potassium phosphate, and phosphoric acid. Alkali metal phosphates such as sodium and alkali metal pyrophosphates such as sodium pyrophosphate and potassium pyrophosphate are used. Further, an aqueous developer composed of water or an aqueous alkali solution and one or more organic solvents can be used. Furthermore, the above-mentioned developing solutions may be used in combination of two or more as required.

  Examples of the development method include a dip method, a battle method, a spray method, brushing, and slapping. Among these, it is preferable to use a high-pressure spray system from the viewpoint of improving the resolution.

  In the method for forming the wavy surface according to the present embodiment, the belt-shaped convex portion 27 may be further cured by performing exposure after development as necessary.

[Second Embodiment]
Moreover, in the electrode sheet 1 of 1st Embodiment, the wavelike surface 26 is the 1st surface of the base film 4, and the some strip | belt-shaped convex arrange | positioned mutually parallel along the direction of Y on the 1st surface. Although the case where it comprises by the part 27 was taken as an example, this invention is not limited to this. For example, the wavy surface 26 may be configured by the concavo-convex portion 28 formed on the first surface of the base film 4 (second embodiment).

(Configuration of electrode sheet)
Hereinafter, the configuration of the electrode sheet 31 according to the present embodiment will be described. In addition, the same reference number is attached | subjected to the same structure as the electrode sheet 1 shown in 1st Embodiment, and the description is abbreviate | omitted. Hereinafter, only differences from the electrode sheet 1 of the first embodiment will be described. FIG. 8 is a perspective view showing an embodiment of the electrode sheet according to the present invention, and FIG. 9 is a cross-sectional view taken along line BB on the lead wiring of the electrode sheet shown in FIG.

As shown in FIG. 8, the electrode sheet 31 is formed with a base film 4, an electrode structure 9 of a mutual capacitive touch panel formed on the first surface of the base film 4, and the electrode structure 9. A plurality of routing wires 25 formed around the region, and a portion of the routing wires 25 formed along the X direction extends along the Y direction intersecting (orthogonal) with the X direction. It is formed in close contact with a corrugated surface 126 that repeats existing valleys and valleys. In addition, in this embodiment, the point by which the wavy surface 126 is comprised only by the uneven | corrugated | grooved part 28 formed in the 1st surface of the base film 4 is different from 1st Embodiment.

  The material of the uneven part 28 is the same as that of the belt-like convex part 27 of the first embodiment.

  8 and 9 has a trapezoidal cross-sectional shape, and includes a flat top surface 28a and a sloped side surface 28b sharing a long side. The sloped side surface 28b has a slope in which the cross-sectional width of the convex portion of the concavo-convex portion 28 gradually increases from the upper side to the lower side of the sloped side surface 28b. Moreover, between the convex parts of the uneven | corrugated | grooved part 28, the flat surface of the base film 4 is not exposed like 1st Embodiment, but the recessed part bottom surface 28c of the uneven | corrugated | grooved part 28 exists.

  As described above, the portion of the routing wiring 25 formed along the X direction is formed in close contact with the corrugated surface 126 that repeats the peaks and valleys extending along the Y direction. If the electrode sheet 31 is curved so as to increase the distance between the crests of the corrugated surface, the routing is fixed along the corrugated surface 126 and its surface. The wiring 25 is deformed so as to have a gentler wave shape. At this time, the distance between the peaks of the routing wiring 25 has a wide wave shape, but the length of the routing wiring 25 itself does not change. Since the stress generated by the curvature of the electrode sheet 31 can be absorbed by the deformation of the wave shape, the lead wiring 25 formed of the metal paste is cracked or the electric resistance is greatly increased. There is nothing to do.

  In addition, the corrugated surface 126 composed only of the concavo-convex portions 28 does not expose the base film 4 as in the first embodiment, so that the wiring 25 is not directly fixed to the base film 4, The influence of the stress generated by the curvature of the electrode sheet 31 is reduced.

  Also in this embodiment, the corrugated surface 126 has a peak-to-valley height difference D of 0.1 to 100 μm and a peak width W of 0.1 to 5 mm as in the first embodiment. preferable. When the height difference D between the peaks and valleys is smaller than 0.1 μm, the stress absorption effect of the uneven portion 28 when the electrode sheet 31 is curved cannot be sufficiently obtained. Further, if the height difference D between the peaks and valleys is larger than 100 μm, it becomes difficult to form the wiring 25 along the wavy surface 126. On the other hand, if the peak width W is smaller than 0.1 mm, it is difficult to form the wiring 25 along the wavy surface 126. On the other hand, when the width W of the mountain is larger than 5 mm, the stress absorbing effect of the uneven portion 28 when the electrode sheet 31 is curved cannot be sufficiently obtained.

  In the example shown in FIG. 9, the sloped side surface 28 b of the concavo-convex portion 28 is formed so as to have a straight cross section. However, similar to the belt-like convex portion 27 of the first embodiment, It can also be formed.

(Method of forming a wavy surface)
Next, a method for forming the wavy surface of the present embodiment will be described with reference to the drawings. In addition, the same reference number is attached | subjected to the same structure as the formation process shown in 1st Embodiment, and the description is abbreviate | omitted.

  FIG. 9 is a cross-sectional view showing another example of the step of forming the wavy surface. Specifically, a dry film resist 14 similar to that of the first embodiment is formed on the surface of the base film 4 on which the electrode structure 9 of the mutual capacitive touch panel is formed, on the surface on the electrode structure 9 side. And a step of laminating so as to adhere to each other (see FIG. 9A) and an exposure step of irradiating a predetermined portion of the photosensitive resin layer 13 on the base film 4 with active light L2 (see FIG. 9B). And a developing step of forming a waved surface by developing the exposed photosensitive resin layer 13 (see FIG. 9C).

  The laminating process of this embodiment is the same as that of the first embodiment.

  The exposure process of this embodiment is different from the mask used in the first embodiment. The shape of the mask 6 used in the present embodiment includes a plurality of translucent portions 6a cut out corresponding to the peak surfaces 28a of the above-described concavo-convex portions 28 and a light-shielding portion 6d that covers a portion where the above-described concavo-convex portions 28 are not formed. A low light-transmitting portion 6c that covers the portion corresponding to the above-described concave bottom surface 28c and that forms a low exposure amount, and covers a portion that corresponds to the above-described sloped side surface 28b, and the light-transmitting portion 6a and the low light-transmitting portion 6c And a gradation portion 6b that gradually changes the exposure amount between them (see FIG. 12). In FIG. 8, the corrugated surface 126 is formed in an L-shaped region, but the mask in FIG. 12 is described as a rectangular region for convenience.

  By using the mask 6 as described above, the part of the photosensitive resin layer 13 covered with the light transmitting part 6a of the mask 6 is cured, and the part of the photosensitive resin layer 13 covered with the light shielding part 6d of the mask 6 is used. Leave uncured. Then, the portion of the photosensitive resin layer 13 covered with the low light-transmitting portion 6c is semi-cured to a certain extent, and the portion of the photosensitive resin layer 13 covered with the gradation portion 6b is separated from the light-transmitting portion 5a. Semi-cured so that the degree of curing gradually decreases.

  In the developing process of this embodiment, the portion of the photosensitive resin layer 13 that has been covered with the light-transmitting portion 6 of the mask 6 remains as it is, and the crest surface 28a of the concavo-convex portion 28 is formed. Further, the uncured portion covered with the light shielding portion 6d of the mask 6 is all removed, and the uneven portion 28 is not formed.

  And the semi-hardened part covered with the low light transmission part 6c remains according to the hardening degree, and the recessed part bottom face 28c of the uneven | corrugated | grooved part 28 is formed. Note that the semi-cured portion covered with the low light-transmissive portion 6c is deformed so as to be crushed during development.

  Moreover, the semi-hardened part covered with the gradation part 6b remains according to a hardening degree, and the side surface 28b with the gradient of the uneven | corrugated | grooved part 28 is formed. The semi-cured portion covered with the gradation portion 6b is deformed so as to be crushed at the time of development, thereby changing from a change in the horizontal direction to a change in the vertical (thickness) direction.

[Other variations]
The electrode sheet of the present invention is not limited to the embodiments shown in the first embodiment and the second embodiment. For example, in the first embodiment and the second embodiment, the example in which the wavy surfaces 26 and 126 are formed on the base film 4 on which the electrode structure 9 of the mutual capacitive touch panel is formed is shown. The formation of the electrode structure 9 and the formation of the corrugated surfaces 26 and 126 may be performed simultaneously.

  In this case, the electrode structure 9 is formed by, for example, laminating the conductive layer 12 only on the support film 11 in the region where the electrode structure 9 is formed, and laminating on the support film 11 and the conductive layer 12. Lamination using a dry film resist 15 including a photosensitive resin layer 13 having a property so that the photosensitive resin layer 13 is in close contact with the surface on the X electrode 10 side of the base film 4 on which the X electrode 10 is formed. And an exposure step of irradiating a predetermined portion of the photosensitive resin layer 13 on the base film 4 with the actinic ray L2, and a development step of developing the exposed photosensitive resin layer 13 to form a conductive pattern. . Through this process, the Y electrode 20 is formed, and the insulating film 3 disposed so as to support the Y electrode 20 is formed between the X electrode 10 and the Y electrode 20. In addition, the formation method of the X electrode 10 can use the various methods quoted in 1st Embodiment and 2nd Embodiment.

  As described in the first and second embodiments, the belt-like convex portion 27 and the concave-convex portion 28 are formed by exposing and developing the photosensitive resin layer 13 of the dry film resist 14 that does not include the conductive layer 12. Yes. Therefore, in the exposure / development process when forming the electrode structure 9 described above, it is possible to simultaneously form the belt-like convex portions 27 and the concave-convex portions 28.

  As another modification, the belt-like convex portion 27 and the concave-convex portion 28 can be formed by the following method. Specifically, the ink 50 composed of a photosensitive resin and a solvent is filled in the recesses of the intaglio roll 51, and after the ink 50 is transferred onto the base film 4, the solvent is evaporated and dried to be in an uncured state. The belt-like convex portion 275 is formed (see FIG. 13a). Next, the cured belt-shaped convex portion 27 is formed by irradiating the cured light beam L2 to the uncured strip-shaped convex portion 275 and curing it (see FIG. 13b).

  In the case of the concavo-convex portion 28, similarly, an ink 50 composed of a photosensitive resin and a solvent is applied onto the intaglio roll 51, and after the ink 50 is transferred onto the base film 4, the solvent is evaporated and dried. An uneven portion 285 in a cured state is formed (see FIG. 14a). Next, the uneven portion 285 in an uncured state is irradiated with an actinic ray L2 and cured to form a cured uneven portion 28 (see FIG. 14b).

  Furthermore, the concavo-convex portion 28 can be formed using the shaping mold 54. First, after forming the above-mentioned photosensitive resin layer 13 on the base film 4, the shaping mold 54 is pressed to deform the photosensitive resin layer 13 to form an uncured uneven portion 285 (see 15a). . Next, the uneven portion 285 in an uncured state is irradiated with an actinic ray L2 to be cured, thereby forming the cured uneven portion 28. (See FIG. 15b).

  Moreover, you may replace the positional relationship of the electrode structure 9 and the base film 4 as another modification. In the first embodiment and the second embodiment, the X electrode 10 and the Y electrode 20 are positioned on the front surface of the base film 4, but the X electrode 10 and the Y electrode 20 are positioned on the back surface of the base film 4. Also good.

  As another modification, the formation direction of the corrugated surfaces 26 and 126 may be changed. For example, in the first embodiment and the second embodiment, a portion formed along the X direction in the routing wiring 25 repeats a valley that extends along the Y direction that intersects (orthogonally) the X direction. Although formed in close contact with the corrugated surfaces 26, 126, XY may be reversed. That is, a portion of the routing wiring 25 formed along the Y direction is formed in close contact with the corrugated surfaces 26 and 126 that repeat the peaks and valleys extending along the X direction intersecting (orthogonal) with the Y direction. be able to.

  In addition, the intersection between the direction in which the peaks and valleys of the wavy surfaces 26 and 126 extend and the wiring direction of the routing wiring 25 may be crossed obliquely instead of orthogonally.

  In the first and second embodiments, the corrugated surfaces 26 and 126 are formed by alternately and continuously arranging trapezoidal peaks and troughs having inverted trapezoidal cross sections. However, the present invention is not limited to this. It is good also as a shape. For example, the wavy surfaces 26 and 126 can be formed in a shape in which a mountain having a triangular cross section and a valley having a V-shaped cross section are alternately arranged. However, the wave shape shown in the first and second embodiments is preferred. Is not an acute angle, the burden on the routing wiring 25 can be reduced.

  Finally, the electrode sheet of the present invention has a patterned transparent electrode, and since each transparent electrode is connected to a lead wiring, it is suitably used for various optical devices. Examples of such a device include a touch panel, a flat panel display such as a liquid crystal display, a plasma display, and an organic EL display, a lighting device, and a solar cell. In the first embodiment and the second embodiment, an example of a mutual capacitance method is shown as a touch panel application, but a touch panel application such as a self-capacitance method or a resistance film method is also possible.

1,31,101 Electrode sheet (touch panel)
3 Insulating film 4, 104 Base film 5, 6 Mask 5a, 6a Translucent part 5b, 6b Gradation part 5d, 6d Light-shielding part 6c Low light-transmitting part 9 Electrode structure v
DESCRIPTION OF SYMBOLS 10,110 X electrode 11 Support film 12 Conductive layer 13 Photosensitive resin layer 14, 15 Dry film resist 20, 120 Y electrode 25, 125 Lead wiring 26, 126 Wave surface 27, 275 Band-shaped convex part 27b Gradient side surface 28, 285 Concavity and convexity 28a Summit surface 28b Gradient side surface 28c Concave bottom surface 50 Ink 51, 52 Intaglio roll 53 Press roll 54 Shaping mold 200 Object (for example, finger)
300 cracks

Claims (9)

A base film having flexibility;
A plurality of transparent electrodes formed of a transparent conductive material having flexibility on the first surface of the base film;
A plurality of lead wires formed of a metal paste around a region where the plurality of transparent electrodes are formed, and electrically connected to each of the plurality of transparent electrodes;
A portion formed along the first direction of the routing wiring is formed in close contact with a corrugated surface that repeats a mountain and valley extending along a second direction intersecting the first direction. An electrode sheet having flexibility.   The electrode sheet having flexibility according to claim 1, wherein the height difference D between the peaks and valleys of the wavy surface is 0.1 to 100 µm, and the width W of the peaks is 0.1 to 5 mm.   The corrugated surface is constituted by a first surface of the base film and a plurality of band-shaped convex portions arranged in parallel to each other along a second direction on the first surface. Or the electrode sheet which has the flexibility in any one of Claim 2.   The flexible electrode sheet according to claim 3, wherein the material of the belt-like convex portion is a photosensitive resin having electrical insulation.   The electrode sheet which has the flexibility in any one of Claim 1 or Claim 2 with which the said wavy surface is comprised by the uneven | corrugated | grooved part formed in the 1st surface of the said base film.   The electrode sheet having flexibility according to claim 5, wherein the material of the uneven portion is a photosensitive resin having electrical insulation.   The electrode sheet which has flexibility in any one of Claims 1-6 whose metal material of the said metal paste of the said routing wiring is silver, copper, aluminum, or nickel.   The electrode sheet having flexibility according to any one of claims 1 to 7, wherein the lead wiring has a thickness of 0.1 to 50 µm. The plurality of transparent electrodes are arranged in parallel to each other along a first direction and are arranged in parallel to each other along a second direction and insulated from the plurality of first electrodes. The electrode sheet which has flexibility in any one of Claims 1-8 provided with the some 2nd electrode and forming the electrode structure of a capacitive touch panel.

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