JP2016164694A - Touch sensor and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a touch sensor to be incorporated in an input manipulation section or the like of various electronic devices and a manufacturing method therefor, the touch sensor having a cover lens-integrated configuration that can be inexpensively achieved and being arranged to keep a manipulating finger or the like closer to a conductive portion of a detection unit compared with conventional products.SOLUTION: A metal pattern 50 is disposed at inner bottom sections of grooves 45 provided on a first surface 41 of a resin substrate 40, and the metal pattern 50 disposed in the grooves 45 is used as a conductive portion of a detection unit 20. The metal pattern 50 includes side end portions 50A that are thinner than a central potion 50B in cross-sectional view. Such an arrangement improves detection accuracy of a touch panel 10 because a manipulating finger or the like is kept closer to the metal pattern 50 disposed as the conductive portion of the detection unit 20 compared with conventional products.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a touch sensor mounted on an input operation unit or the like of various electronic devices and a method for manufacturing the touch sensor.

  Various electronic devices such as smartphones perform input operations by touching the input operation unit with fingers or the like.

  The input operation unit includes a cover lens and a capacitive touch sensor. The cover lens is light transmissive. The cover lens is flat and made of resin or glass.

  The touch sensor is light transmissive. Note that the configuration of the touch sensor will be described later.

  The input operation unit has a configuration in which a cover lens with a touch sensor is disposed at a front position of a display device disposed in the device. The cover lens with a touch sensor is configured by bonding a cover lens and a touch sensor with an adhesive.

  The user operates the surface of the cover lens with a finger while visually confirming the display content of the display device in the device via the cover lens with a touch sensor.

  The configuration of the capacitive touch sensor will be described below. The touch sensor usually has a base part and a detection part formed in a thin film on the surface of the base part. A base material part consists of a resin film with transparency. The resin film is made of polyethylene terephthalate (PET) resin or polycarbonate (PC) resin. The detection unit has light transparency. The detector has conductivity and is made of, for example, ITO. Alternatively, the detection unit is a transparent resin in which conductive nanowires are dispersed.

  As prior art document information related to the invention of this application, for example, Patent Document 1 and Patent Document 2 are known.

JP 2012-174003 A JP 2012-181828 A

  When the capacitive touch sensor is made of an ITO detection unit, the cost is increased in terms of material costs and processing steps. The same applies to a detection unit including conductive nanowires. That is, the configuration of the conventional product has a limit in obtaining a capacitive touch sensor at low cost.

  Further, the cover lens with a touch sensor is configured by bonding a surface opposite to the surface having the detection part of the touch sensor to the cover lens. The user uses the electronic device by touching the surface of the cover lens exposed to the electronic device on which the cover lens with the touch sensor is mounted.

  Here, the user who uses an electronic device requests | requires the improvement of the detection accuracy at the time of touch operation. In the conventional touch sensor, the conductive part of the detection unit is arranged so as to overlap the surface of the base member. For this reason, there is a limit in improving the detection accuracy by reducing the distance between the conductive portion of the detection unit and the finger being operated. In addition, it is necessary to suppress a misalignment between the cover lens and the touch sensor.

  The present invention solves such a conventional problem, and can obtain a cover lens integrated component at a low cost, and further, the distance between the conductive portion of the detection unit and the finger during operation is more than that of the conventional product. An object of the present invention is to provide a touch sensor having a configuration close to the touch sensor and a method for manufacturing the touch sensor.

  In order to achieve the above object, the touch sensor according to the present invention uses a resin base material having a groove on the first surface. Then, a metal pattern made of a conductive metal is disposed on the inner bottom portion of the groove. That is, the touch sensor uses a metal pattern in the groove as a conductive portion of the detection unit. The metal pattern has a cross-sectional shape in the groove width direction perpendicular to the extending direction of the groove, a side end disposed in the vicinity of the side wall of the groove, and the vicinity of the center of the groove formed integrally with the side end. And a central portion disposed in the. And the depth dimension from a 1st surface to a side edge part is a shape larger than the depth dimension from a 1st surface to a center part.

  The method for manufacturing a touch sensor according to the present invention includes the following steps. In the first step, a base material portion having grooves on the first surface is formed with a predetermined resin. In the second step, a conductive metal film is formed from the first surface side with respect to the base material portion. In the third step, the conductive metal film attached to the side wall portion of the groove of the base material portion is removed, and then a first resin film is formed on the first surface side of the base material portion. Then, the conductive metal film and the first resin film in portions other than the inside of the groove in the base material portion are removed, and a metal pattern and a first resin layer are formed in the groove. In the fourth step, the liquid second resin liquid is applied from the first surface side including the groove of the base material portion so as to form the second resin layer overlapping the first surface so as to cover the first resin layer. To.

  The touch sensor by this invention has arrange | positioned the metal pattern used as the electroconductive part of a detection part in a groove | channel. For this reason, it is possible to make the distance between the conductive portion of the detection unit and the finger being operated closer to that of the conventional product in a state where the electronic device is mounted. In addition, it is possible to provide an advantageous effect that it is possible to provide a touch sensor and a method for manufacturing the touch sensor that can be inexpensively adapted to cover lens integrated components.

The external appearance perspective view of the smart phone carrying the touch sensor by embodiment of this invention Exploded perspective view of smartphone Block diagram schematically showing the configuration of the smartphone Cross section of touch sensor View of touch sensor from below The figure which expands and shows the principal part in FIG. The figure explaining the manufacturing method of a touch sensor The figure explaining the manufacturing method of a touch sensor The figure explaining the manufacturing method of a touch sensor The figure explaining the manufacturing method of a touch sensor The figure explaining the manufacturing method of a touch sensor The figure explaining the manufacturing method of a touch sensor The figure explaining the manufacturing method of a touch sensor The figure explaining the manufacturing method of a touch sensor The perspective view which shows the modification of a touch sensor

  A touch sensor and a touch sensor manufacturing method according to the present invention will be described below with reference to the drawings.

(Embodiment)
1 is an external perspective view of a smartphone equipped with a touch sensor according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of the smartphone, FIG. 3 is a block diagram schematically showing the configuration of the smartphone, and FIG. 4 is a cross section of the touch sensor. 5 is a view of the touch sensor as viewed from below, and FIG. 6 is an enlarged view of the main part in FIG. FIG. 4 shows a cross-sectional position at the detection unit of the touch sensor. 7 to 14 are diagrams for explaining a method for manufacturing a touch sensor, and FIG. 15 is a perspective view showing a modification of the touch sensor.

  The touch sensor 10 according to the embodiment of the present invention is a capacitance type and has light transmittance. The touch sensor 10 has a cover lens integrated type. The touch sensor 10 is mounted on, for example, the smartphone 100 (see FIG. 1).

  As shown in FIGS. 1 and 2, the smartphone 100 includes an outer frame-shaped housing 110. The touch sensor 10 is disposed at a front position of the housing 110.

  As shown in FIG. 3, the housing 110 includes a display device 120, a microphone 130, a speaker 140, and the like. A wiring board is disposed in the housing 110. The wiring board has a first control unit 210 and a second control unit 220. Further, a radio wave transmission / reception unit 250 and the like are configured on the wiring board. The display device 120 is disposed behind the touch sensor 10.

  As shown in FIG. 3, the first control unit 210 is connected to various functional parts such as the display device 120, the microphone 130, and the speaker 140. The 1st control part 210 has a function which controls the above-mentioned various functional parts. The second control unit 220 is connected to the first control unit 210.

  Three side switch units 300 (see FIG. 1) are arranged in the casing 110. Each side switch 300 is also connected to the first controller 210 (see FIG. 3). For example, when one of the side surface switch units 300 is pressed, the first control unit 210 that detects the switch signal causes the screen on the display device 120 to be changed.

  As shown in FIG. 3, the touch sensor 10 is connected to the second control unit 220. That is, the second control unit 220 has a function of controlling the touch sensor 10. In other words, the second controller 220 detects a change in capacitance that occurs in the touch sensor 10. Then, the second control unit 220 outputs a predetermined signal corresponding to the detection result to the first control unit 210.

  For example, the user brings a finger or the like close to the touch sensor 10 or performs a touch operation on the touch sensor 10. The second control unit 220 that has detected this operation state generates a corresponding signal and sends it to the first control unit 210. And the 1st control part 210 performs predetermined control of various functional parts.

  As described above, the smartphone 100 includes the touch sensor 10 and various functional parts.

  Next, the touch sensor 10 will be described.

  As shown in FIGS. 4 to 6, the touch sensor 10 includes a main body 15 formed in a flat plate shape. The main body unit 15 includes a plurality of detection units 20. In addition, illustration of the flexible wiring board etc. with which the main-body part 15 is mounted | worn is abbreviate | omitted.

  The plurality of detection units 20 are provided on the base material unit 40. The base material part 40 consists of resin which has a light transmittance, and is flat form. The base material portion 40 has a first surface 41 and a second surface 42 that faces the first surface 41. The first surface 41 of the base material part 40 has a plurality of grooves 45. Here, the first surface 41 of the base material portion 40 refers to a portion other than the groove 45. And the 1st surface 41 is a plane of the same height position. The material of the base material portion 40 is, for example, a light transmissive resin such as polycarbonate (PC) resin, polyethylene terephthalate (PET) resin, polymethyl methacrylate (PMMA) resin, or cyclic olefin resin.

  As shown in FIG. 4, the groove 45 provided on the first surface 41 of the base material portion 40 has an inner bottom portion 46 and a side wall portion 47. The groove 45 has a shape that opens at the same height as the first surface 41.

  A metal pattern 50 is disposed on the inner bottom 46 of the groove 45. A first resin layer 61 is disposed in the groove 45 so as to overlap and cover the metal pattern 50. That is, the first resin layer 61 is provided such that the surface opposite to the surface covering the metal pattern 50 is set at a height located in the groove 45. The second resin layer 62 overlaps the first surface 41 so as to cover the first resin layer 61. The 1st resin layer 61 and the 2nd resin layer 62 are comprised only with resin. The first resin layer 61 and the second resin layer 62 are also light transmissive. The shape of the metal pattern 50 will be described later.

  Thus, the detection unit 20 includes the base material part 40, the groove 45 provided in the base material part 40, the metal pattern 50 on the inner bottom part of the groove 45, the first resin layer 61, and the second resin layer 62. It is comprised including.

  Here, the cover lens integrated type touch sensor 10 needs to ensure strength. On the other hand, it is necessary to obtain a predetermined amount of change in capacitance during operation. The base material portion 40 in the touch sensor 10 is set to a thickness that can satisfy these. The required thickness of the base material portion 40 depends on the characteristics of the resin used. For example, if it is the base material part 40 made from PC resin, it is good to ensure intensity | strength as the base material part 40 about 1 mm or thicker than that. If the thickness of the base material portion 40 is too thick, it is difficult to obtain a change in capacitance that occurs in the detection portion 20 when the user operates. For this reason, if it is the base material part 40 made from PC resin, it is good to make thickness into the thickness to about 3 mm, desirably thinner than about 3 mm.

  The touch sensor 10 is light transmissive and transmits the display content of the display device. You may make it the structure of the touch sensor 10 which does not have light transmittance, and mount it in a corresponding electronic device.

  The cover lens-integrated touch sensor 10 operates the second surface 42 side of the base member 40 with a finger or the like. For this reason, a functional film (for example, hard coat layer 70) or the like is provided on the second surface 42 to constitute the operation surface. In addition to the hard coat layer 70, the functional film formation is a layer having, for example, an antireflection function or an anti-fingerprint function. The hard coat layer 70 shown in FIG. 4 may have an antireflection function or an anti-fingerprint function. Or you may make it the structure which laminated | stacked the several layer which has those functions on the 2nd surface 42. FIG.

  As shown in FIGS. 5 and 6, the shape of each detection unit 20 is a rectangular shape having the same size. The plurality of detection units 20 are arranged in a matrix form independently of each other. Each of the detection units 20 has a corresponding drawer unit 25. Each drawer part 25 is drawn to the outer edge position of the main body part 15. Each detection unit 20 is connected to the second control unit 220 via a corresponding drawing unit 25 and a flexible wiring board (not shown). The shape and arrangement state of the detection unit 20 may be other than the above configuration.

  Each detection part 20 is comprised including the groove | channel 45 (refer FIG. 4) as mentioned above. The groove 45 of the detection unit 20 includes a rectangular outer frame in plan view and a mesh shape that intersects with each other in the outer frame (see FIG. 6). All the grooves 45 have the same width, and the grooves 45 are connected to each other. Similarly, each drawer | drawing-out part 25 is comprised including the groove | channel 45 mutually connected. It is preferable to arrange the grooves 45 in the outer frame in a regular arrangement because the first surface 41 composed of the remaining portions other than the grooves 45 is regularly arranged in the same area.

  All of the connected plurality of grooves 45 have the same depth dimension from the first surface 41. That is, as shown in FIG. 4, the inner bottom portion 46 of each groove 45 is provided at the same height position in a cross-sectional view in a direction orthogonal to the extending direction. The inner bottom 46 of the groove 45 is not limited to a flat surface.

  A metal pattern 50 is disposed on the inner bottom portion 46 of the groove 45. The metal pattern 50 is made of a conductive metal. The formation width of the metal pattern 50 covers substantially the entire groove width in the groove 45. The metal pattern 50 is covered with a first resin layer 61 disposed in the groove 45, and the first resin layer 61 and the first surface 41 are covered with a second resin layer 62.

  The conductive portions of the individual detection units 20 and the lead-out units 25 of the touch sensor 10 are configured by metal patterns 50 in the grooves 45.

  The groove width in the groove 45 is 0.5 μm to 3 μm. The depth of the groove 45 is 0.5 μm to 10 μm. In the detection unit 20, the spaces between the one grooves 45 constituting the mesh shape in the outer frame have a parallel relationship of 50 μm to 1000 μm pitch. The other grooves 45 are parallel to each other with a pitch of 50 μm to 1000 μm. One groove 45 and the other groove 45 intersect each other in an orthogonal relationship and are connected to each other.

  The material of the metal pattern 50 is made of a conductive metal such as copper, silver, aluminum, gold, and their alloys.

  Here, a cross-sectional shape of the metal pattern 50 (a shape in a cross-sectional view in a direction orthogonal to the extending direction of the groove 45) will be described. 4, the metal pattern 50 includes a side end portion 50A in the vicinity of the side wall portion 47 of the groove 45 and a central portion 50B in the vicinity of the center of the groove 45 in a cross-sectional view. Shape. The side end portion 50A and the central portion 50B are integrally formed. The thickness of the central portion 50B is 0.5 μm to 3 μm.

  The thickness of the side end portion 50A is thinner than the thickness of the central portion 50B. In other words, the depth dimension from the first surface 41 to the surface opposite to the inner bottom portion 46 in the side end portion 50A is the depth dimension from the first surface 41 to the surface opposite to the inner bottom portion 46 in the central portion 50B. Big against. That is, the side wall portion 47 of the groove 45 is exposed to a height position closer to the inner bottom portion 46 side than the height position of the thickness of the central portion 50B disposed so as to overlap the inner bottom portion 46. An exposed portion of the side wall 47 near the metal pattern 50 is covered with the first resin layer 61.

  The metal pattern 50 having a width or thickness of 3 μm or less can hardly be visually recognized. In other words, it has a so-called light-transmitting state. For this reason, the width of the groove 45 is set with reference to the width of the metal pattern 50 being 3 μm or less.

  In order to obtain a so-called transparent touch panel, the metal pattern 50 having a width and thickness of 3 μm or less is configured to include the detection unit 20 disposed on the transparent resin base material unit 40.

  The inner bottom portions 46 of the grooves 45 are at the same height, and the metal patterns 50 having the above-described thickness and width are provided on all the inner bottom portions 46 of the connected grooves 45. With this configuration, it is possible to easily realize a transparent touch panel in which the metal pattern 50 is arranged in the groove 45 in the same mesh shape as the connection shape of the plurality of grooves 45 in plan view. In addition, if it is the mesh-shaped metal pattern 50, generation | occurrence | production of a perfect disconnection state can also be prevented.

  The groove 45 may have a shape other than a rectangle in a cross-sectional view. In other words, any shape may be used as long as the deep portion becomes the inner bottom portion 46 and the side wall portions 47 that face each other are connected to the inner bottom portion 46. That is, the shape of the inner bottom portion 46 may be a curved surface shape, a polygonal shape, or the like other than a flat surface. Further, the side wall portion 47 may be other than provided in a parallel relationship.

  The first resin layer 61 and the second resin layer 62 are so-called insulating resists. The first resin layer 61 is made of, for example, a light-transmitting acrylic resin. The second resin layer 62 is made of, for example, an acrylic resin having light transparency. The first resin layer 61 and the second resin layer 62 of the same type may be used in order to suppress the types of materials used. Also in the 1st resin layer 61 arrange | positioned in the groove | channel 45, it arrange | positions in the same mesh shape as the connection shape of the some groove | channel 45 by planar view.

  The first resin layer 61 in the groove 45 is provided with a thickness of 0.5 μm to 3 μm overlapping the central portion 50B of the metal pattern 50. The thickness of the second resin layer 62 is 0.5 μm to 3 μm at the portion overlapping the first surface 41. Note that the surface of the second resin layer 62 opposite to the base 40 is preferably a flat surface having the same height.

  A functional film, such as a hard coat layer 70, is provided over the second surface 42.

  The touch sensor 10 is configured as described above.

  The touch sensor 10 is mounted on the electronic device with the first surface 41 side of the base member 40 facing the inside of the housing 110 (see FIG. 1). In the state mounted in the electronic device, the second surface 42 side of the base material portion 40 is exposed outward to become an operation surface.

  Next, an input operation state to the smartphone 100 equipped with the cover lens integrated type touch sensor 10 will be described.

  The user displays various icons on the display device 120 of the smartphone 100. In this state, the user touches the exposed operation surface of the touch sensor 10 corresponding to the desired icon with a finger. In accordance with the touch operation, the capacitance of the corresponding detection unit 20 of the touch sensor 10 changes. This change in capacitance is detected by the second controller 220 through the drawer 25. The second control unit 220 outputs a predetermined signal corresponding to the detection result to the first control unit 210. In response to a predetermined signal from the second control unit 220, the first control unit 210 changes the display of the display device 120 to the next screen corresponding to the operated desired icon, for example.

  Here, the detection accuracy of the touch sensor 10 is superior to the detection accuracy of the conventional product. That is, when the touch sensor 10 is operated, the charge of the metal pattern 50 moves to the operated finger. As a result, the capacitance of the operated portion changes.

  The conventional product has a detection unit configured to overlap the surface of the base material unit. And the surface opposite to the detection part side of a base material part is bonded together to a cover lens. The user performs an input operation on the surface of the cover lens opposite to the attachment side.

  On the other hand, the touch sensor 10 according to the present invention arranges the metal pattern 50 of the detection unit 20 on the inner bottom portion 46 of the groove 45. That is, the metal pattern 50 is disposed within the thickness of the base material portion 40. In other words, the metal pattern 50 is arranged in a positional relationship approaching the finger that is being operated, and thus the amount of charge that moves to the finger that is being operated increases. That is, the amount of change in capacitance at the operated location changes greatly. For this reason, the touch sensor 10 can improve the detection accuracy as compared with the conventional product.

  Furthermore, since the touch sensor 10 is a cover lens integrated type, the adhesive that bonds the conventional product and the cover lens can be eliminated. The elimination of the pressure-sensitive adhesive contributes to thinning of the electronic device. In addition, the distance between the finger being operated and the metal pattern 50 is further reduced.

  Next, a method for manufacturing the touch sensor 10 will be described with reference to FIGS.

  7-14 is a figure explaining the manufacturing method of the touch sensor 10. FIG.

  As shown in FIG. 7, the manufacturing method includes a first step 810 that is a base material portion forming step, a second step 820 that is a film forming step, a third step 830 that is a main portion forming step, and a second resin coating. The touch sensor 10 is manufactured including the 4th process 840 used as a formation process. The third step 830 includes a plurality of steps, details of which will be described later.

  In the first step 810 (base material forming step), a resin such as polycarbonate is injection-molded to obtain an in-process product 410 shown in FIG. The work in process 410 has a first surface 41 and a second surface 42 that face each other. On the first surface 41 of the work-in-progress item 410, a groove 45 is provided at a location constituting the detection unit 20 or the drawer unit 25. The groove 45 includes an inner bottom portion 46 and a side wall portion 47 and is connected to each other in a mesh shape or the like in plan view. That is, in the first step 810, the base material portion 40 itself is formed as the work-in-process 410.

  Here, the grooves 45 connected to each other have the same depth dimension from the first surface 41 to the inner bottom portion 46. The groove width of the groove 45 (the dimension between the side wall parts 47 connected to the inner bottom part 46) is 0.5 μm to 3 μm. The work-in-process 410 having the groove 45 may be obtained by a method other than molding. For example, the work-in-progress 410 having the groove 45 may be obtained by performing laser processing on a flat base member having flat front and back surfaces.

  The work-in-progress 410 may be formed as a single piece. Alternatively, it may be formed in a large shape so that a plurality of base material portions 40 can be taken.

  Next, the second process 820 (film forming process) is performed on the work-in-process 410. As a result, the work-in-process 420 shown in FIG. 9 is obtained. The work in process 420 includes the conductive metal film 500 including the inside of the groove 45. That is, in the second step 820, a conductive metal film 500 made of a conductive metal such as copper is formed on the first surface 41 side of the base material portion 40. As a film forming method, a sputtering method or a vapor deposition method may be used. Alternatively, other methods may be used.

  As shown in the enlarged view shown in FIG. 9, the conductive metal film 500 includes a first portion 510 that overlaps the first surface 41, a second portion 520 that overlaps the inner bottom portion 46 of the groove 45, and a side wall portion 47 of the groove 45. And a third portion 530 attached to the surface. The first portion 510 and the second portion 520 have substantially the same thickness. Here, in the manufacturing method, the metal pattern 50 is obtained from the second portion 520 through a third step 830 described later. For this reason, the thickness of the 2nd part 520 is provided in the thickness which ensures thickness (for example, 0.5 micrometer-3 micrometers) required in the center part 50B of the metal pattern 50, after passing through the 3rd process 830 mentioned later.

  Note that when the conductive metal film 500 is formed by the sputtering method, most of the metal atoms ejected from the target surface form the first portion 510 and the second portion 520. Some of the ejected metal atoms adhere to the side wall portion 47 to form the third portion 530. For this reason, the third portion 530 is thinner than the first portion 510 and the second portion 520 and tends to have a low crystallinity. In addition, the degree of crystallinity is often low at the first portion 510 and the second portion 520 near the side wall 47.

  Next, a third step 830 (main part forming step) is performed on the work-in-progress 420. As shown in FIG. 7, the third step 830 includes a first step 831 for performing an etching process, a second step 832 for forming the first resin film, and a third step for removing unnecessary portions of the first resin film. Step 833 and a fourth step 834 for removing the first portion 510 of the conductive metal film 500 are included.

  First, the first step 831 is performed on the work-in-progress 420. As a result, the work-in-process 430 shown in FIG. 10 is obtained.

  In the first step 831, the work-in-progress 420 is etched with a diluted etchant. This etching process is performed to remove the third portion 530 having a low degree of crystallinity. The degree of dilution of the etchant is set as appropriate depending on the degree of removal of the third portion 530 and the like while taking into consideration the time and temperature for etching. In the first step 831, an etching solution diluted by 1.5 times to 15 times, for example, with respect to a normal etching solution is used.

  Since the work-in-process 430 after performing the first step 831 has the third portion 530 removed as shown in FIG. 10, the side wall 47 is exposed. Here, the first portion 510 and the second portion 520 having low crystallinity near the side wall 47 are also slightly removed. On the other hand, the first portion 510 and the second portion 520 other than the vicinity of the side wall 47 of the work-in-process 430 are not removed and remain almost as they are.

  That is, the work-in-process 430 after the first step 831 has a configuration in which the metal pattern 50 having the shape described above is provided in the groove 45. In other words, through the first step 831, the second portion 520 includes the side end portion 50 </ b> A near the side wall 47 of the groove 45 and the central portion 50 </ b> B near the center of the groove 45 in a cross-sectional view. It is formed in a metal pattern 50 having an elliptical shape. That is, in the first step 831, the side end portion 50A that overlaps the inner bottom portion 46 is formed, so that the side wall portion 47 of the groove 45 is closer to the inner bottom portion 46 side than the height position of the thickness of the central portion 50B. It will be exposed to the position.

  Next, the second step 832 of the third process is performed on the work-in-process 430. That is, the liquid first resin liquid is applied to the work-in-process 430 on the first surface 41 side of the base material portion 40. The spin coating method is preferably used, but the coating method is not limited. In addition, if it is set as the large size which can take a part corresponding to the base material part 40, it will be excellent in production efficiency. The viscosity of the first resin liquid is adjusted so that the groove 45 is filled with the first resin liquid.

  Thereafter, the applied first resin liquid is cured, and as shown in FIG. 11, a first resin film 600 is formed on the work-in-process 440 having the first surface 41 side. The curing means is not particularly limited. In order to shorten the curing time and the like, it is preferable to use a resin material made of a UV curable resist material as the first resin liquid.

  The first resin film 600 is provided so as to fill the groove 45 so as to overlap the metal pattern 50 in the groove 45. It is desirable that the exposed surface of the first resin film 600 opposite to the base material portion 40 has substantially the same height including the position corresponding to the groove 45.

  Furthermore, as the thickness setting of the first resin film 600, the thickness from the exposed surface to the first portion 510 (dimension B in FIG. 11) is arranged so as to overlap the inner bottom portion 46 of the groove 45 from the first surface 41. The thickness of the metal pattern 50 is made thinner than the thickness up to the central portion 50B (C dimension in FIG. 11). In other words, the depth of the groove 45 and the thickness of the conductive metal film 500 are set so as to be the first resin film 600 having the above relationship. And the formation thickness of the 1st resin film 600 is also managed and provided. When the first resin liquid is applied using the spin coating method, the cross section formed by the side end portion 50A of the metal pattern 50 disposed in the groove 45 even if the groove 45 is present on the first surface 41. Even if there is a triangular space, the first resin liquid can be uniformly applied as a whole and the height position of the application surface can be made uniform. That is, it is preferable because the first resin film 600 in which the height positions of all the exposed surfaces are aligned can be easily formed. As a method other than the spin coating method, a rubbing method (squeegee method) may be used in which the first resin liquid is applied and then the surface is scraped with an elastic material such as urethane or silicone. Even in this case, as in the spin coating method, it is possible to easily obtain the first resin film 600 in which the height positions of all the exposed surfaces are aligned.

  In the third step 833 of the third step, the work-in-process 450 (see FIG. 12) from which unnecessary portions of the first resin coating 600 are removed is formed.

  For example, the unnecessary portion of the first resin film 600 is removed by an etching process using oxygen gas. At the time of this removal, the removal of the first resin film 600 that covers the metal pattern 50 in the groove 45 also proceeds. Here, in the work-in-process 440, the first resin film 600 is formed including the inside of the groove 45 due to the relationship between the B dimension and the C dimension described above. In this case, the first resin film 600 overlapping the first portion 510 of the conductive metal film 500 is removed, and the first resin film 600 in the groove 45 is maintained at a predetermined thickness. That is, the first resin layer 61 is composed of the first resin film 600 maintained in the groove 45. Through this third step 833, a work-in-process 450 having the first resin layer 61 in the groove 45 is obtained as shown in FIG. The first portion 510 of the conductive metal film 500 overlapping the first resin layer 61 and the first surface 41 in the work-in-process 450 is exposed.

  Subsequently, in a fourth step 834, a work-in-process 460 (see FIG. 13) from which the first portion 510 of the conductive metal film 500 has been removed is formed. For example, in the case of the conductive metal film 500 made of a copper material, the first portion 510 overlapping the first surface 41 is removed by performing an etching process on copper. As a result, the work-in-process 460 shown in FIG. 13 is obtained.

  The work-in-process 460 has a metal pattern 50 disposed so as to overlap the inner bottom portion 46 in the groove 45. The metal pattern 50 of the work-in-process 460 is covered with the first resin layer 61 in the groove 45. Further, the first surface 41 of the base material portion 40 itself of the work-in-process 460 is exposed. In the work-in-process 460, the height position of the surface of the first resin layer 61 is preferably slightly depressed with respect to the first surface 41 or the same height.

  In the manufacturing method, the third portion 530 of the conductive metal film 500 is removed in the first step 831 and the fourth step 834 is performed. For example, in the state where the third portion 530 is included at the time of the fourth step 834, the third portion 530 is removed at the fourth step 834, and there is a possibility that the metal pattern 50 may be affected. In order to eliminate this, the first step 831 is inserted, and the etching process of the fourth step 834 is performed thereafter. If this is the case, the influence on the metal pattern 50 in the fourth step 834 can be reduced.

  In the fourth step, the liquid second resin liquid is applied to the work-in-process 460 from the first surface 41 side. Then, the second resin liquid is cured to form a work-in-process 470 shown in FIG. That is, the work-in-process 470 is configured to have the second resin layer 62 that covers the first surface 41 side including the position of the groove 45. The second resin layer 62 is preferably provided so as to have a uniform surface height position.

  Note that the viscosity of the second resin liquid is adjusted so that the groove 45 is filled with the second resin liquid in the applied state, similarly to the application of the first resin liquid. Desirably, a spin coating method is used as a coating method of the second resin liquid.

  Thereafter, a functional film such as the hard coat layer 70 is provided on the second surface 42 side of the work-in-process 470 to complete the main body 15 of the touch sensor 10. In the case of forming in a large shape, the outer shape is punched and formed on the individual main body 15 of the touch sensor 10.

  The formation timing of the functional film such as the hard coat layer 70 may be performed after the first step. In the case of the cover lens integrated type touch sensor 10, the function film on the second surface 42 side is operated with a finger or the like. That is, functional film formation with a flat surface is desirable. For this reason, it is preferable to form the functional film using the spin coat method.

  Subsequently, the touch sensor 10 is formed by attaching a flexible wiring board to the main body 15.

  As described above, with the manufacturing method, the touch sensor 10 can be produced by a simple process. As described above, the touch sensor 10 is a component in which the distance between the metal pattern 50 serving as the conductive portion of the detection unit 20 and the finger is closer than that of the conventional product. The touch sensor 10 does not use expensive ITO or conductive nanowires as the material of the conductive portion such as the detection unit 20 including the manufacturing method. For this reason, it is possible to provide the touch sensor 10 having an inexpensive configuration. Further, when the spin coating method is used as in the manufacturing method, the first resin liquid and the second resin liquid can be applied to the same height in a short time and can be efficiently formed even in a large size. This also contributes to obtaining an inexpensive and high-quality touch sensor 10.

  Furthermore, in the manufacturing method, the cover lens integrated touch sensor 10 can be manufactured by forming the base material portion 40 with a predetermined thickness. The cover lens integrated type touch sensor 10 does not require a bonding process to the cover lens as in the conventional product when mounted on an electronic device. Further, it is possible to eliminate the cause of the bonding deviation in the bonding process. Note that the touch sensor 10 may be used in a form of being attached to a cover lens. In this case, the thickness of the base material portion 40 may be set to a corresponding thickness at the time of manufacture.

  Note that the first step 831 of the third step 830 may be performed as necessary. For example, when the conductive metal film 500 is formed, the first step 831 may be omitted when there is almost no third portion 530 formed on the side wall 47 of the groove 45. In this case, the metal pattern 50 has a shape without the side end portion 50A.

  In addition, the touch sensor 10 comprised including the base-material part 40 which is flat shape and is not bent above was demonstrated. However, if it is the said manufacturing method, it is also possible to obtain the touch sensor 10A of the modification shown in FIG. The touch sensor 10A has a shape in which only the lateral direction side is formed in an arc shape.

  In order to manufacture the touch sensor 10 </ b> A, in the first step described above, only the short side is formed on the base material having an arc shape. The same process is used after the second process thereafter. Even if the touch sensor 10A has a curved shape on the first surface and the second surface of the base material, application of the first resin liquid or the like is easy when the spin coating method is used. In addition, instead of making only the short direction side into an arc shape like the touch sensor 10A, only the longitudinal direction side is made into an arc shape, or a convex shape or a concave shape connected in a curved surface is the same. It is.

  In addition, you may apply the detection part 20 which made the metal pattern 50 in the groove | channel 45 the electroconductive part as a detection part of the component which bonded the 1st plate-shaped member and the 2nd plate-shaped member, for example. That is, this component has a plurality of strip-shaped detection portions extending in the X direction in the first plate-shaped member, arranged in parallel, and a plurality of strip-shaped detection portions extending in the Y direction in the second plate-shaped member, An array is formed and the first plate member and the second plate member are bonded together. All or a part of these detection units may be provided by the metal pattern 50. In addition, you may make it the structure to which the metal pattern 50 was applied even if it is other than the touch sensor 10 and 10A and the above-mentioned component.

  In the above description, the touch sensor 10 or 10 </ b> A having optical transparency has been described as being mounted on the smartphone 100. The touch sensors 10 and 10A may be mounted for input operation units of various electronic devices in addition to the smartphone 100. For example, the touch sensors 10 and 10A may be disposed and mounted at a location where the display content does not need to be visually recognized. In this case, since the light transmissivity of the touch sensors 10 and 10A is not necessary, it is possible to increase the selection range of materials used in configuring the touch sensors 10 and 10A and to further reduce the cost. Note that an electronic device on which a touch sensor that does not require light transmission is mounted is not particularly limited. For example, an operation panel in a passenger compartment of an automobile.

  The touch sensor and the touch sensor manufacturing method according to the present invention can provide a touch sensor integrated with a cover lens at a lower cost, closer to the distance between the conductive portion of the detection unit and the finger being operated than the conventional product. It is useful mainly for the input operation unit of various electronic devices.

DESCRIPTION OF SYMBOLS 10, 10A Touch sensor 15 Main body part 20 Detection part 25 Drawer part 40 Base part 41 1st surface 42 2nd surface 45 Groove 46 Inner bottom part 47 Side wall part 50 Metal pattern 50A Side edge part 50B Center part 61 1st resin layer 62 Second resin layer 70 Hard coat layer 100 Smartphone 110 Housing 120 Display device 130 Microphone 140 Speaker 210 First control unit 220 Second control unit 250 Transmission / reception unit 300 Side switch units 410, 420, 430, 440, 450, 460, 470 Work in process 500 Conductive metal film 510 1st part 520 2nd part 530 3rd part 600 1st resin coating 810 1st process 820 2nd process 830 3rd process 831 1st step 832 2nd step 833 3rd step 834 4th Step 840 4th process

Claims (12)

A base material having a groove on the first surface;
A metal pattern disposed on the inner bottom of the groove,
The metal pattern is integrally formed with a side end portion disposed in the vicinity of the side wall portion of the groove and the side end portion in a cross-sectional view in the groove width direction orthogonal to the extending direction of the groove, and is formed in the center of the groove. A central portion disposed in the vicinity, and a depth dimension from the first surface to the side end portion is larger than a depth dimension from the first surface to the central portion,
A touch sensor characterized in that the metal pattern is used as a conductive portion of a detection unit. A first resin layer covering the metal pattern in the groove;
The touch sensor according to claim 1, further comprising a second resin layer that overlaps the first surface so as to cover the first resin layer. The touch sensor according to claim 1, wherein a plurality of the grooves are provided and connected to each other, and an inner bottom portion of the grooves is formed at the same depth with respect to the first surface. The touch sensor according to claim 1, wherein the base material portion is formed of a light-transmitting resin, and the metal pattern has a width of 0.5 μm to 3 μm. The touch sensor according to claim 1, wherein a material of the metal pattern is copper, silver, aluminum, gold, or an alloy thereof. The touch sensor according to claim 1, wherein a functional film is provided on a second surface facing the first surface of the base material portion to form an operation surface. A first step of forming a base portion having a groove on the first surface with a predetermined resin;
A second step of forming a conductive metal film on the first surface of the base material part including the inside of the groove;
The conductive metal film adhering to the side wall portion of the groove of the base material portion is removed, and a liquid first resin liquid is applied to the first surface side of the base material portion, and then the first resin liquid is applied. To form a first resin film,
A third step of removing the conductive metal film and the first resin film in places other than the inside of the groove in the base material portion to form a metal pattern and a first resin layer covering the metal pattern in the groove;
A liquid second resin liquid is applied from the first surface side of the base material portion, and then the second resin liquid is cured to overlap the first surface so as to cover the first resin layer. And a fourth step of forming a resin layer. The touch sensor manufacturing method according to claim 7, wherein in the third step, the first resin liquid is applied by a spin coating method or a rubbing method. The thickness of the first resin film formed in the third step from the exposed surface of the first resin film to the conductive metal film overlapping the first surface is from the first surface to the inside of the groove. The touch sensor manufacturing method according to claim 7, wherein the touch sensor is thinner than a thickness of the metal pattern overlapping the bottom. The touch sensor manufacturing method according to claim 7, wherein in the fourth step, the second resin liquid is applied by a spin coating method. The method for manufacturing a touch sensor according to claim 7, wherein a predetermined resin that forms the base portion is a light-transmitting resin, and the metal pattern has a width of 0.5 μm to 3 μm. The touch sensor manufacturing method according to claim 7, wherein the functional film is formed by spin coating on the second surface side of the base portion.

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