Touch sensor manufacturing method and touch sensor

Abstract

The invention relates to a manufacturing method of a touch sensor and the touch sensor. The technical problem to be solved is to provide a touch sensor and a manufacturing method of the touch sensor capable of preventing peripheral wiring from being broken. A method for manufacturing a touch sensor, the method including the following steps in this order: a step for preparing a substrate including a detection region and a peripheral region; a step for forming a metal layer in the peripheral region; a step in which a photosensitive resist is patterned on the metal layer by photolithography, wet etching is performed on the metal layer, and a detection electrode connection terminal, an external connection terminal, and a peripheral wiring connecting the detection electrode connection terminal and the external connection terminal are formed; a step for forming a plating layer that is formed in the detection region, extends so as to cover at least a portion of each of the detection electrode connection terminals, and includes a pattern comprising a plurality of thin wires; and a step for forming a touch detection electrode, which is electrically connected to the detection electrode connection terminal, on the plating layer by a wet plating method.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a touch sensor for detecting a touch operation and the touch sensor. Background Art

[0002] Touch sensors for detecting so-called touch operations of fingers, styluses, etc. touching or approaching a screen have been used in various electronic devices, including tablet computers and smart phones. Such touch sensors generally include touch detection electrodes formed on a detection area of ​​a substrate and detecting touch operations, external connection terminals formed on a peripheral area of ​​the substrate located around the detection area and used to electrically connect the touch sensor to an external device, and peripheral wiring formed on the peripheral area and electrically connecting the touch detection electrodes and the external connection terminals.

[0003] Here, when manufacturing a touch sensor, it is often the case that touch detection electrodes, external connection terminals, and peripheral wiring are simultaneously formed on a substrate for ease of manufacturing. In this case, a so-called plating method disclosed in, for example, Patent Document 1 can be used. In this case, after a plated layer having a pattern corresponding to the touch detection electrodes, external connection terminals, and peripheral wiring is formed on the substrate, the substrate is immersed in an electroplating solution to precipitate metal on the plated layer, thereby forming the touch detection electrodes, external connection terminals, and peripheral wiring.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2013-051391

[0005] In recent years, in order to narrow the peripheral area, it is necessary to narrow the line width of the peripheral wiring and the distance between the adjacent peripheral wirings. However, if the touch detection electrodes and external connection terminals are formed on the substrate at the same time as the peripheral wiring with a narrow line width and a narrow distance between the wirings by a plating method such as disclosed in Patent Document 1, bubbles generated during the plating process or impurities mixed in for some reason are located on the plated layer corresponding to the peripheral wiring, thereby causing the peripheral wiring finally formed to be disconnected. Summary of the invention

[0006] The present invention has been made to solve such a problem, and an object of the present invention is to provide a method for manufacturing a touch sensor and a touch sensor that can prevent disconnection of peripheral wiring.

[0007] The above-mentioned object can be achieved according to the following structure.

[0008] [1] A method for manufacturing a touch sensor, comprising:

[0009] A step of preparing a substrate including a detection region and a peripheral region disposed around the detection region;

[0010] The step of forming a metal layer in the peripheral area of ​​the substrate;

[0011] A step of patterning a photosensitive resist on a surface of a metal layer by photolithography and wet-etching the metal layer to thereby form a plurality of detection electrode connection terminals, a plurality of external connection terminals, and a plurality of peripheral wirings connecting the plurality of detection electrode connection terminals and the plurality of external connection terminals;

[0012] a step of forming a plated layer formed in the detection region of the substrate and extending to cover at least a portion of each of the plurality of detection electrode connection terminals and including a pattern composed of a plurality of fine lines; and

[0013] A step of forming a plurality of touch detection electrodes electrically connected to the plurality of detection electrode connection terminals on the plated layer by a wet plating method.

[0014] [2] The method for manufacturing a touch sensor according to [1], wherein:

[0015] The method further includes forming a first protective layer covering at least the plurality of peripheral wirings between the step of forming the plurality of detection electrode connection terminals, the plurality of external connection terminals, and the plurality of peripheral wirings and the step of forming the plated layer.

[0016] [3] The method for manufacturing a touch sensor according to [2], further comprising the step of forming a second protective layer covering the touch detection electrode.

[0017] [4] The method for manufacturing a touch sensor according to [3], wherein:

[0018] The composition of the first protective layer and the composition of the second protective layer are different from each other.

[0019] [5] The method for manufacturing a touch sensor according to any one of [1] to [4], wherein:

[0020] The plated layer is formed by photolithography.

[0021] [6] A touch sensor comprising:

[0022] A substrate including a detection area and a peripheral area disposed around the detection area;

[0023] A plurality of detection electrode connection terminals are arranged in the peripheral area of ​​the substrate;

[0024] A plurality of external connection terminals are arranged in the peripheral area of ​​the substrate;

[0025] A plurality of peripheral wirings are arranged in the peripheral area of ​​the substrate and connect the plurality of detection electrode connection terminals and the plurality of external connection terminals to each other;

[0026] a plated layer formed in the detection region of the substrate and extending to cover at least a portion of each of the plurality of detection electrode connection terminals and including a pattern consisting of a plurality of fine lines; and

[0027] The plurality of touch detection electrodes and at least a portion of each of the plurality of detection electrode connection terminals are disposed on the plated layer and are electrically connected to the plurality of detection electrode connection terminals.

[0028] [7] A touch sensor according to [6], wherein:

[0029] The distance between the plurality of peripheral wirings adjacent to each other is 15.00 μm or less.

[0030] [8] A touch sensor according to [6] or [7], wherein:

[0031] The layer to be plated has an organic substance as a main component and contains a palladium catalyst.

[0032] Effects of the Invention

[0033] According to the present invention, the manufacturing method of the touch sensor includes in sequence: a process of preparing a substrate including a detection area and a peripheral area arranged around the detection area; a process of forming a metal layer in the peripheral area of ​​the substrate; a process of patterning a photosensitive resist on the surface of the metal layer by photolithography, and wet-etching the metal layer to form a plurality of detection electrode connection terminals, a plurality of external connection terminals, and a plurality of peripheral wirings connecting the plurality of detection electrode connection terminals and the plurality of external connection terminals to each other; a process of forming a plated layer that is formed in the detection area of ​​the substrate and extends in a manner covering at least a portion of each of the plurality of detection electrode connection terminals and includes a pattern composed of a plurality of fine lines; and a process of forming a plurality of touch detection electrodes electrically connected to the plurality of detection electrode connection terminals on the plated layer by wet plating, thereby preventing the peripheral wiring from being disconnected. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a partial cross-sectional view of a touch sensor according to an embodiment.

[0035] Figure 2 is a top view of a touch sensor according to an embodiment.

[0036] Figure 3 It is a plan view showing a part of the touch detection electrode in the embodiment in an enlarged manner.

[0037] Figure 4 It is a plan view showing part of a plurality of peripheral wirings in an enlarged manner in the embodiment.

[0038] Figure 5This is a cross-sectional view showing an enlarged portion of the first conductive layer in the embodiment.

[0039] Figure 6 It is a schematic diagram showing a method for manufacturing a touch sensor according to an embodiment.

[0040] Figure 7 It is a plan view of a substrate on which detection electrode connection terminals, peripheral wiring, and external connection terminals are formed.

[0041] Figure 8 This is an enlarged cross-sectional view showing a portion of a substrate on which detection electrode connection terminals, peripheral wirings, and external connection terminals are formed.

[0042] Fig. 9 It is a cross-sectional view showing, in an enlarged manner, a part of a substrate on which a layer to be plated is formed. DETAILED DESCRIPTION

[0043] Hereinafter, a conductive member for a touch panel and a touch panel according to the present invention will be described in detail based on preferred embodiments shown in the drawings.

[0044] In addition, the expression "to" indicating a numerical range includes the values ​​on both sides. For example, "s is a value t1 to a value t2" means that the range of s includes the range of values ​​t1 and t2, and if expressed in mathematical notation, it is t1≤s≤t2.

[0045] Unless otherwise specified, angles including "perpendicular" and "parallel" include an error range generally allowed in the technical field.

[0046] "Transparent" means that the light transmittance is at least 40% or more, preferably 75% or more, more preferably 80% or more, and even more preferably 90% or more in the visible light wavelength region of 400nm to 800nm. The light transmittance is measured using "Plastics - Method for determining total light transmittance and total light reflectance" specified in JIS K7375:2008.

[0047] Implementation

[0048] Figure 1 Detailed Description of the Invention The structure of a touch sensor according to an embodiment of the present invention is shown in FIG.

[0049] The touch sensor includes: a substrate 1 having a first surface 1A and a second surface 1B forming a front surface and a back surface of each other; a first conductive layer 2 disposed on the first surface 1A of the substrate 1; and a second conductive layer 3 disposed on the second surface 1B of the substrate 1. The substrate 1 has insulating properties, and the first conductive layer 2 and the second conductive layer 3 are electrically insulated from each other. In addition, the substrate 1 has flexibility, and the touch sensor has flexibility that matches the flexibility of the substrate 1. In addition, the substrate 1 is made of a transparent material.

[0050] The touch sensor can be used as a touch panel display device (not shown) by bonding a cover member (not shown) to the surface on the side of the first conductive layer 2 and bonding a display module (not shown) to the surface on the side of the second conductive layer 3. In this case, the user's finger, stylus pen, etc. that is in contact with or close to the cover member is detected, thereby detecting the user's touch operation.

[0051] Figure 2 A top view of the touch sensor is shown in . The substrate 1 has a detection region R1 and a peripheral region R2 arranged around the detection region R1.

[0052] The first conductive layer 2 includes: a plurality of touch detection electrodes 11 formed in the detection region R1 and extending along a predetermined Y direction and arranged along an X direction orthogonal to the Y direction for detecting touch operations; a plurality of detection electrode connection terminals 12 formed in the peripheral region R2 and formed at one end of the plurality of touch detection electrodes 11; a plurality of external connection terminals 14 formed in the peripheral region R2 and used for electrical connection to an external device not shown; and a plurality of peripheral wirings 13 formed in the peripheral region R2 and electrically connecting the plurality of detection electrode connection terminals 12 and the plurality of external connection terminals 14. Although described later, the first conductive layer 2 in the detection region R1 includes a plated layer covering the plurality of touch detection electrodes 11.

[0053] The second conductive layer 3 includes: a plurality of touch detection electrodes 21 formed in the detection region R1 and extending along the X direction and arranged along the Y direction for detecting touch operation; a plurality of detection electrode connection terminals 22 formed in the peripheral region R2 and formed at one end of the plurality of touch detection electrodes 21; a plurality of external connection terminals 24 formed in the peripheral region R2 and used for electrical connection with an external device not shown; and a plurality of peripheral wirings 23 formed in the peripheral region R2 and electrically connecting the plurality of detection electrode connection terminals 22 and the plurality of external connection terminals 24. Although described later, the second conductive layer 3 in the detection region R1 includes a plated layer covering the plurality of touch detection electrodes 21.

[0054] Although described in detail later, the plurality of detection electrode connection terminals 12, the plurality of peripheral wirings 13, and the plurality of external connection terminals 14 can be formed by, for example, forming a metal layer on the first surface 1A of the substrate 1 in the peripheral region R2, patterning a photosensitive resist on the metal layer by so-called photolithography, and performing so-called wet etching on the metal layer. Furthermore, the plurality of touch detection electrodes 11 can be formed by, for example, forming a plated layer on the first surface 1A of the substrate 1 in the detection region R1 after forming the plurality of detection electrode connection terminals 12, the plurality of peripheral wirings 13, and the plurality of external connection terminals 14, and depositing metal on the plated layer by so-called wet plating.

[0055] In addition, multiple touch detection electrodes 21, multiple detection electrode connection terminals 22, multiple peripheral wirings 23 and multiple external connection terminals 24 can also be formed on the second surface 1B side of the substrate 1 by the same method as the multiple touch detection electrodes 11, multiple detection electrode connection terminals 12, multiple peripheral wirings 13 and multiple external connection terminals 14.

[0056] like Figure 3 As shown, the touch detection electrode 11 in the first conductive layer 2 is composed of a plurality of metal fine wires M forming a grid shape. In order to suppress the generation of so-called interference ripples when an observer visually recognizes the touch detection electrode 11 configured on a display module not shown in the figure, the average value of the line width W1 of the plurality of metal fine wires M is preferably 0.50 μm to 3.00 μm, and more preferably in the range of 1.00 μm to 2.00 μm.

[0057] like Figure 4 As shown, the peripheral wiring 13 in the first conductive layer 2 has a line width W2. In addition, the plurality of peripheral wirings 13 are arranged at the closest locations to each other with a distance L2 between the wirings. In order to ensure the conductivity of the peripheral wirings 13 and narrow the peripheral region R2, the line width W2 of the peripheral wirings 13 and the distance L2 between the wirings are preferably, for example, 1.00 μm or more and 30.00 μm or less, and more preferably 5.00 μm or more and 15.00 μm or less.

[0058] Figure 5 A cross-sectional view of a touch sensor showing the boundary portion of the detection area R1 and the peripheral area R2 of the substrate 1 is shown in FIG. The detection electrode connection terminal 12 of the first conductive layer 2 is formed on the first surface 1A of the substrate 1 in the peripheral area R2. A plated layer 31 is formed on the first surface 1A of the substrate 1 in the detection area R1. The plated layer 31 is a layer in which the metal constituting the plurality of touch detection electrodes 11 is precipitated by a wet plating method, and contains a catalyst such as a palladium (Pd) catalyst that promotes the precipitation of the metal. The plated layer 31 extends toward the peripheral area R2 in a manner covering at least a portion of the detection electrode connection terminal 12. Furthermore, the plated layer 31 has the same shape pattern as the plurality of touch detection electrodes 11, and is composed of a plurality of fine lines. The plurality of touch detection electrodes 11 are formed on the plated layer 31 by a wet plating method.

[0059] The touch detection electrode 11 is formed by a wet plating method, and is thus formed to cover the side portion 31A of the plated layer 31. As a result, the portion of the touch detection electrode 11 formed on the side portion 31A of the plated layer 31 is in contact with the detection electrode connection terminal 12, and the touch detection electrode 11 and the detection electrode connection terminal 12 are reliably electrically connected to each other without being affected by the height difference between the detection region R1 and the peripheral region R2 in the first conductive layer 2 caused by the touch detection electrode 11 and the detection electrode connection terminal 12 being formed separately.

[0060] In addition, although not Figure 5 , the peripheral wiring 13 and the external connection terminal 14 are formed on the first surface 1A of the substrate 1 in the peripheral region R2 in the same manner as the detection electrode connection terminal 12. Figure 5 In order to simplify the description, the second conductive layer 3 is omitted, but the second conductive layer 3 also has a layer structure in which the touch detection electrode 21 is formed on the plated layer 31, and the detection electrode connecting terminal 22, the plated layer 31, and the touch detection electrode 21 are stacked in sequence from the second surface 1B of the substrate 1 in the edge of the peripheral area R2 toward the detection area R1.

[0061] Here, the touch sensor can also have a first protective layer (not shown) covering at least the plurality of peripheral wirings 13 and 23. For example, when the plated layer 31 is formed as a composition containing a catalyst or when a catalyst is applied to the surface of the plated layer 31 after the formation of the plated layer 31, the first protective layer can prevent the catalyst from being attached between the plurality of peripheral wirings 13 and the plurality of peripheral wirings 23, thereby preventing metal from being deposited between the plurality of peripheral wirings 13 and the plurality of peripheral wirings 23 and causing a short circuit.

[0062] Furthermore, in order to mechanically protect the plurality of touch detection electrodes 11 and 21 , the touch sensor may include a second protection layer (not shown) that covers the plurality of touch detection electrodes 11 and 21 .

[0063] In order to prevent the catalyst from adhering to the plurality of peripheral wirings 13 and 23, the first protective layer is preferably made of a material that prevents liquid from entering. Furthermore, when the touch panel is used in a state where it is arranged on a display module (not shown), for example, the second protective layer is preferably made of a transparent material while mechanically protecting the plurality of touch detection electrodes 11 and 21. In this way, the compositions of the first protective layer and the second protective layer can be made different from each other according to their purposes.

[0064] Next, use Figure 6 A method for manufacturing a touch sensor according to an embodiment of the present invention is described with reference to a schematic diagram of FIG.

[0065] First, in step S1, a substrate 1 is prepared. The substrate 1 is divided into a detection region R1 and a peripheral region R2.

[0066] In step S2, a metal layer is formed on first surface 1A and second surface 1B in peripheral region R2 of substrate 1 prepared in step S1. The metal layer can be formed by a so-called dry plating method such as vacuum deposition or sputtering.

[0067] In step S3, by processing the metal layer formed in step S2, a plurality of detection electrode connection terminals 12, a plurality of peripheral wirings 13 and a plurality of external connection terminals 14 are formed on the first surface 1A of the substrate 1 in the peripheral area R2, and a plurality of detection electrode connection terminals 22, a plurality of peripheral wirings 23 and a plurality of external connection terminals 24 are formed on the second surface 1B of the substrate 1 in the peripheral area R2.

[0068] At this time, first, a photosensitive resist liquid is applied to the metal layer formed on the first surface 1A of the substrate 1, and the applied photosensitive resist is heated and dried for a predetermined time. A photomask having an exposure pattern corresponding to the plurality of detection electrode connection terminals 12, the plurality of peripheral wirings 13, and the plurality of external connection terminals 14 is arranged to be close to or in contact with the dried photosensitive resist, and in this state, ultraviolet rays are irradiated to the photosensitive resist through the photomask. Then, by immersing the substrate 1 in a developer corresponding to the photosensitive resist, the photosensitive resist pattern is formed into a shape corresponding to the plurality of detection electrode connection terminals 12, the plurality of peripheral wirings 13, and the plurality of external connection terminals 14.

[0069] In a state where the photosensitive resist formed in such a pattern is arranged on the metal layer, the substrate 1 is immersed in an etching solution to wet-etch the metal layer, and the photosensitive resist is removed using a resist stripping solution, thereby forming a substrate 1 as shown in FIG. Figure 7 The plurality of detection electrode connection terminals 12, the plurality of peripheral wirings 13 and the plurality of external connection terminals 14 are shown. Figure 8 As shown, near the boundary between the detection region R1 and the peripheral region R2 , the detection electrode connection terminals 12 are arranged on the first surface 1A of the substrate 1 in the peripheral region R2 , but are not formed in the detection region R1 .

[0070] In addition, as the photosensitive resist used in step S3, a so-called negative photosensitive resist or a so-called positive photosensitive resist can be used. Furthermore, any etching solution used in wet etching can be used as long as it is a solution that dissolves the metal layer.

[0071] Furthermore, the plurality of detection electrode connection terminals 22 , the plurality of peripheral wirings 23 , and the plurality of external connection terminals 24 can be formed on the second surface 1B of the substrate 1 by the same method as the plurality of detection electrode connection terminals 12 , the plurality of peripheral wirings 13 , and the plurality of external connection terminals 14 .

[0072] In step S4, a plated layer 31 having a shape pattern corresponding to the plurality of touch detection electrodes 11 and extending so as to cover at least a portion of each of the plurality of detection electrode connecting terminals 12 is formed on the first surface 1A of the substrate 1 in the detection area R1, and a plated layer 31 having a shape pattern corresponding to the plurality of touch detection electrodes 21 and extending so as to cover at least a portion of each of the plurality of detection electrode connecting terminals 22 is formed on the second surface 1B of the substrate 1 in the detection area R1.

[0073] At this time, a liquid composition composed of a photosensitive resin material is applied to the first surface 1A of the substrate 1 and the plurality of detection electrode connection terminals 12 in the detection area R1, and the applied liquid composition is heated and dried for a predetermined time to form a plated precursor layer. A photomask having an exposure pattern corresponding to the plurality of touch detection electrodes 11 is arranged to contact the plated precursor layer, and in this state, ultraviolet rays are irradiated to the plated precursor layer through the photomask. Then, by cleaning the substrate 1, a plated layer 31 having a shape pattern corresponding to the plurality of touch detection electrodes 11 is formed.

[0074] Furthermore, the plated layer 31 contains a catalyst such as a Pd catalyst for promoting the precipitation of metal by the wet plating method. As a method for imparting a catalyst to the plated layer 31, for example, a method of mixing a catalyst on a plated layer precursor layer, a method of stacking a layer containing a catalyst on the surface of the plated layer precursor layer, a method of patterning the plated layer precursor layer and then treating it with a treatment solution containing a catalyst, etc. can be cited.

[0075] like Fig. 9 As shown, the catalyst-containing plated layer 31 formed in this way is formed on the first surface 1A of the substrate 1 in the detection region R1 and extends toward the peripheral region R2 so as to cover at least a portion of the detection electrode connection terminal 12 .

[0076] The layer to be plated 31 on the second surface 1B side of the substrate 1 can be formed on the second surface 1B of the substrate 1 by the same method as that for the layer to be plated 31 on the first surface 1A side of the substrate 1 .

[0077] In step S5, a plurality of touch detection electrodes 11 electrically connected to a plurality of detection electrode connection terminals 12 and a plurality of touch detection electrodes 21 electrically connected to a plurality of detection electrode connection terminals 22 are formed by wet plating on the plated layer 31 on the first surface 1A side and the second surface 1B side of the substrate 1 formed in step S4.

[0078] like Figure 5 As shown in the figure, the touch detection electrode 11 formed in this way is formed in a manner covering the side portion 31A of the plated layer 31. Therefore, the portion of the touch detection electrode 11 formed on the side portion 31A of the plated layer 31 is in contact with the detection electrode connection terminal 12, and the touch detection electrode 11 and the detection electrode connection terminal 12 are reliably electrically connected to each other. Although not shown in the figure, the touch detection electrode 21 formed on the second surface 1B side of the substrate 1 is also electrically connected to the detection electrode connection terminal 22 in the same manner as the touch detection electrode 11 formed on the first surface 1A side.

[0079] When step S5 is completed, the manufacturing of the touch sensor according to the embodiment of the present invention is completed.

[0080] Here, in general, when manufacturing a touch sensor, in order to facilitate manufacturing, for example, multiple touch detection electrodes 11, multiple detection electrode connection terminals 12, multiple peripheral wirings 13, and multiple external connection terminals 14 are often formed together. At this time, if, for example, a wet plating method is used, bubbles generated during the plating process or impurities mixed in for some reason are arranged at any position of the multiple peripheral wirings 13, thereby forming any of the multiple peripheral wirings 13 in a disconnected state or uneven plating occurs on the touch detection electrode 11. In addition, if, for example, a method of wet etching the metal layer is used, it is difficult to thin the touch detection electrode 11, and there is a possibility that, for example, when a photosensitive resist formed by a pattern arranged on the metal layer is removed by ultrasonic cleaning, any of the multiple metal thin wires M constituting the multiple touch detection electrodes 11 is mechanically disconnected.

[0081] In the manufacturing method of the touch sensor of the present invention, a plurality of detection electrode connection terminals 12, a plurality of peripheral wirings 13 and a plurality of external connection terminals 14 are formed by etching the metal layer, and then a plurality of touch detection electrodes 11 are formed by a wet plating method. Therefore, the plurality of peripheral wirings 13 and the plurality of metal fine wires M constituting the plurality of touch detection electrodes 11 can be prevented from being broken during the manufacturing process.

[0082] In addition, the metal layer can be formed by dry plating in step S2, but it can also be formed by wet plating. In this case, for example, a plated layer is formed on the first surface 1A and the second surface 1B of the substrate 1 in the peripheral region R2, and the substrate 1 is immersed in the plating solution, thereby forming a metal layer on these plated layers. The metal layer formed in this way is wet-etched in step S3, thereby forming a plurality of detection electrode connection terminals 12, a plurality of peripheral wirings 13, and a plurality of external connection terminals 14 on the first surface 1A side of the substrate 1, and forming a plurality of detection electrode connection terminals 22, a plurality of peripheral wirings 23, and a plurality of external connection terminals 24 on the second surface 1B side.

[0083] Furthermore, in the manufacturing process of the touch sensor, between the step S3 of forming a plurality of detection electrode connection terminals 12 and 22, a plurality of peripheral wirings 13 and 23, and a plurality of external connection terminals 14 and 24 and the step S4 of forming the plated layer 31, a step of forming a first protective layer (not shown) that covers at least the plurality of peripheral wirings 13 and 23 may be included.

[0084] Furthermore, in the manufacturing process of the touch sensor, after the step S5 of forming the plurality of touch detection electrodes 11 and 21 , a step of forming a second protective layer (not shown) covering the plurality of touch detection electrodes 11 and 21 may be included.

[0085] Hereinafter, each component constituting the touch sensor according to the embodiment will be described.

[0086] <Substrate>

[0087] The type of the substrate 1 is not particularly limited as long as it can support the first conductive layer 2 and the second conductive layer 3 , and examples thereof include a plastic substrate, a glass substrate, and a metal substrate, and a plastic substrate is preferred.

[0088] The substrate 1 is preferably flexible in terms of excellent bendability. Examples of the flexible substrate include the above-mentioned plastic substrates.

[0089] The thickness of the substrate 1 is not particularly limited, but is generally 25 μm to 500 μm.

[0090] As a material constituting the substrate 1, preferably, a resin having a melting point of about 290° C. or less, such as polyethylene terephthalate (PET), polycycloolefin, polycarbonate, acrylic film, polyethylene naphthalate, polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, and triacetylcellulose, is used, and PET, polycycloolefin, or polycarbonate is more preferred. Among them, PET is particularly preferred from the viewpoint of excellent adhesion with the first conductive layer 2 and the second conductive layer 3.

[0091] The total light transmittance of the substrate 1 is preferably 85% to 100%. The total light transmittance is measured using "Plastics - Method for determining total light transmittance and total light reflectance" specified in JIS (Japanese Industrial Standards) K7375:2008.

[0092] As one of the preferred embodiments of the substrate 1, a substrate treated with at least one treatment selected from the group consisting of atmospheric pressure plasma treatment, corona discharge treatment, and ultraviolet irradiation treatment can be cited. By implementing the above treatment, hydrophilic groups such as OH groups are introduced into the surface of the treated substrate 1, and the adhesion between the substrate 1 and the first conductive layer 2 and the adhesion between the substrate 1 and the second conductive layer 3 are improved. Among the above treatments, atmospheric pressure plasma treatment is preferred in terms of further improving the adhesion between the substrate 1 and the first conductive layer 2 and the adhesion between the substrate 1 and the second conductive layer 3.

[0093] <Base coating>

[0094] In order to improve the adhesion between the substrate 1 and the first conductive layer 2 and the adhesion between the substrate 1 and the second conductive layer 3, a primer layer can be respectively arranged between the substrate 1 and the first conductive layer 2 and between the substrate 1 and the second conductive layer 3. The primer layer contains a polymer, and further improves the adhesion between the substrate 1 and the first conductive layer 2 and the adhesion between the substrate 1 and the second conductive layer 3.

[0095] The method for forming the primer layer is not particularly limited, and for example, a method of applying a primer layer-forming composition containing a polymer on the substrate 1 and performing a stretching treatment as required can be cited. In addition, as the primer layer-forming composition containing a polymer, gelatin, acrylic resin, polyurethane resin, acrylic / styrene latex containing inorganic or polymer particles, etc. can also be used.

[0096] In addition, as required, the touch sensor may include a refractive index adjusting layer other than the above-mentioned primer layer as another layer between the substrate 1 and the first conductive layer 2 and between the substrate 1 and the second conductive layer 3. As the refractive index adjusting layer, for example, an organic layer to which particles of a metal oxide such as zirconium oxide that adjusts the refractive index are added can be used.

[0097] <Touch detection electrodes, detection electrode connection terminals, peripheral wiring, external connection terminals>

[0098] The touch detection electrodes 11 and 21, the detection electrode connection terminals 12 and 22, the peripheral wirings 13 and 23, and the external connection terminals 14 and 24 are formed of metal or alloy, for example, they can be formed of silver, copper, gold, aluminum, nickel, chromium, molybdenum or tungsten. It is preferred that the touch detection electrodes 11 and 21, the detection electrode connection terminals 12 and 22, the peripheral wirings 13 and 23, and the external connection terminals 14 and 24 contain copper, but may also contain metals other than copper, such as gold, silver, etc. In addition, the detection electrode connection terminals 12 and 22, the peripheral wirings 13 and 23, and the external connection terminals 14 and 24 may have a stacked structure of metal and metal compounds. In this case, metal fine wires with a stacked structure such as copper / copper oxide, copper / copper sulfide, etc. can be used.

[0099] <Layer to be plated>

[0100] The plated layer 31 is mainly composed of organic matter. The main component is organic matter, which means that the content of organic matter relative to the total mass of the plated layer 31 exceeds 50 mass %, preferably 80 mass % or more, and more preferably 90 mass % or more. The upper limit is not particularly limited and can be 100 mass %.

[0101] The plated layer 31 is preferably a layer having a functional group (hereinafter, also referred to as "interactive group") that interacts with the electroplating catalyst or its precursor. Interactive group refers to a functional group that can interact with the electroplating catalyst or its precursor given to the plated layer 31, for example, a functional group that can form an electrostatic interaction with the electroplating catalyst or its precursor and a nitrogen-containing functional group, a sulfur-containing functional group and an oxygen-containing functional group that can form coordination with the electroplating catalyst or its precursor can be cited. As the interactive group, from the viewpoint of high polarity and high adsorption capacity to the electroplating catalyst or its precursor, it is preferably an ionic polar group or a cyano group such as a carboxylic acid group, a sulfonic acid group, a phosphoric acid group and a boric acid group, and more preferably a carboxylic acid group or a cyano group. The plated layer 31 usually contains a compound with the above-mentioned interactive group. As a compound, it is preferably a polymer. That is, the plated layer 31 preferably contains a polymer containing a repeating unit with an interactive group.

[0102] Furthermore, the plated layer 31 preferably contains a plating catalyst or a precursor thereof. As the plating catalyst or its precursor, an electroless plating catalyst or its precursor is preferably used. The electroless plating catalyst is not particularly limited as long as it is a catalyst that becomes an active nucleus during electroless plating, and for example, a metal having a catalytic performance of an autocatalytic reduction reaction (a metal known as a metal capable of electroless plating with a lower ionization tendency than Ni) can be cited. Specifically, Pd, Ag, Cu, Pt, Au, Co, etc. can be cited.

[0103] The manufacturing method of the plated layer 31 is not particularly limited. For example, the following method can be cited: a plated layer precursor layer is formed by applying a plated layer forming composition on the substrate 1, the plated layer precursor layer is subjected to exposure treatment and development treatment to form a plated layer 31 having a shape pattern corresponding to the touch detection electrode 11, and the obtained plated layer 31 is further given an electroplating catalyst or its precursor.

[0104] The composition for forming a layer to be plated contains the following compound X or composition Y.

[0105] Compound X: Compound with interactive groups and polymerizable groups

[0106] Composition Y: a composition comprising a compound having an interactive group and a compound having a polymerizable group

[0107] Compound X is a compound having an interactive group and a polymerizable group. The definition of the interactive group is as described above. In addition, compound X may have two or more types of interactive groups.

[0108] The polymerizable group is a functional group that can form a chemical bond by energy imparting, for example, a free radical polymerizable group and a cationic polymerizable group can be cited. Among them, from the viewpoint of being more excellent in reactivity, a free radical polymerizable group is preferably used. As a free radical polymerizable group, a methacryloyloxy group, an acryloyloxy group or a styryl group is more preferably used. Compound X may have more than two polymerizable groups. In addition, the number of polymerizable groups possessed by compound X is not particularly limited, and may be one, or may be more than two.

[0109] The compound X may be a low molecular weight compound or a high molecular weight compound. A low molecular weight compound refers to a compound having a molecular weight of less than 1000, and a high molecular weight compound refers to a compound having a molecular weight of 1000 or more. When the compound X is a polymer, the weight average molecular weight of the polymer is not particularly limited, but is preferably 1000 to 700000, and more preferably 2000 to 200000, in terms of better solubility and other handling properties. The method for synthesizing the polymer having such a polymerizable group and an interactive group is not particularly limited, and a known synthesis method is used (see paragraphs

[0097] to

[0125] of Japanese Patent Application Laid-Open No. 2009-280905).

[0110] Composition Y is a composition comprising a compound having an interactive group and a compound having a polymerizable group. That is, composition Y comprises both a compound having an interactive group and a compound having a polymerizable group. The definitions of the interactive group and the polymerizable group are as described above. The compound having an interactive group can be a low molecular compound or a macromolecular compound. In addition, the compound having an interactive group can include a polymerizable group. As a preferred embodiment of the compound having an interactive group, a polymer (e.g., polyacrylic acid) comprising a repeating unit having an interactive group can be cited.

[0111] As a preferred embodiment of the polymer containing repeating units having an interactive group, in terms of being easy to form the plated layer 31 with a small amount of energy applied (e.g., exposure), there can be cited a polymer Z having repeating units derived from a conjugated diene compound and repeating units derived from an unsaturated carboxylic acid or a derivative thereof. The conjugated diene compound is not particularly limited as long as it is a compound having a molecular structure having two carbon-carbon double bonds separated by one single bond.

[0112] The repeating unit derived from the conjugated diene compound is preferably a repeating unit derived from a compound having a butadiene skeleton. Examples of the compound having a butadiene skeleton (monomer having a butadiene structure) include 1,3-butadiene, isoprene, 2-ethyl-1,3-butadiene, 2-n-propyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 1-phenyl-1,3-butadiene, 1-α-naphthyl-1,3-butadiene, 1-β-naphthyl-1,3-butadiene, 2-chloro-1,3-butadiene, 1-bromo-1,3-butadiene, 1-chloroprene, 2-fluoro-1,3-butadiene, 2,3-dichloro-1,3-butadiene, 1,1,2-trichloro-1,3-butadiene, and 2-cyano-1,3-butadiene.

[0113] The content of the repeating unit derived from the conjugated diene compound in the polymer Z is preferably 25 to 75 mol% based on all the repeating units. The content of the repeating unit derived from the unsaturated carboxylic acid or its derivative in the polymer Z is preferably 25 to 75 mol% based on all the repeating units.

[0114] The compound having a polymerizable group is a so-called monomer, and a polyfunctional monomer having two or more polymerizable groups is preferred in terms of the better hardness of the formed plated layer 31. Specifically, the polyfunctional monomer is preferably a monomer having 2 to 6 polymerizable groups. From the perspective of the mobility of the molecules in the cross-linking reaction that affects the reactivity, the molecular weight of the polyfunctional monomer used is preferably 150 to 1000, and more preferably 200 to 800.

[0115] The composition for forming the plated layer may contain components other than the above components. For example, the composition for forming the plated layer may contain a polymerization initiator. The type of polymerization initiator is not particularly limited, and a known polymerization initiator (preferably a photopolymerization initiator) may be mentioned. The composition for forming the plated layer may contain a solvent. The type of solvent is not particularly limited, and water and an organic solvent may be mentioned. As the organic solvent, a known organic solvent (for example, an alcohol solvent, an ester solvent, a ketone solvent, a halogen solvent, a hydrocarbon solvent, etc.) may be mentioned.

[0116] Example

[0117] (Example 1)

[0118] The materials, usage amounts, ratios, processing contents and processing steps shown in the following examples can be appropriately changed without departing from the purpose of the present invention, and the scope of the present invention should not be interpreted in a restrictive manner by the following examples.

[0119] (Substrate Preparation)

[0120] As the substrate 1 , an optical PET film having a thickness of 75 μm (manufactured by Toyobo Co., Ltd.: COSMOSHINE A4360) was prepared.

[0121] (Formation of Metal Layer)

[0122] On the first surface 1A of the prepared optical PET film, a nickel layer of 0.05 μm was formed by sputtering as a base layer for improving adhesion with metal, and then a copper layer of 0.5 μm was deposited as a metal layer.

[0123] (Formation of Multiple Detection Electrode Connection Terminals, Multiple Peripheral Wiring Lines, and Multiple External Connection Terminals)

[0124] A positive photosensitive resist was applied to the metal layer by a roller coating method with a thickness of about 2.00 μm, and dried at 110°C for 2 minutes. Then, a photomask having an exposure pattern corresponding to a plurality of detection electrode connection terminals 12, a plurality of peripheral wirings 13, and a plurality of external connection terminals 14 was overlapped and close exposure was performed with a high-pressure mercury lamp, and an alkaline solution was used for development to form a photosensitive resist pattern corresponding to a plurality of detection electrode connection terminals 12, a plurality of peripheral wirings 13, and a plurality of external connection terminals 14. Next, the metal layer was etched with a ferric chloride (FeCl3) solution and then cleaned with pure water. Finally, the photosensitive resist was peeled off to obtain a plurality of detection electrode connection terminals 12, a plurality of peripheral wirings 13, and a plurality of external connection terminals 14.

[0125] (Formation of the First Protective Layer)

[0126] An ultraviolet curable ink (UVF-10T (KAI) manufactured by Asahi Chemical Research Laboratory Co., Ltd.) was applied to the plurality of peripheral wirings 13 by screen printing. Then, a high pressure mercury lamp was used at 800 mJ / cm 2 The applied ultraviolet curing ink was irradiated with ultraviolet rays and cured, thereby forming a first protective layer having a thickness of about 6.00 μm for protecting the plurality of peripheral wirings 13 .

[0127] (Preparation of Composition for Forming Layer to be Plated)

[0128] The following components were mixed to obtain a composition for forming a layer to be plated.

[0129] Isopropyl alcohol 38 parts by mass

[0130] Polybutadiene maleic acid (butadiene-maleic acid alternating copolymer, repeating units derived from butadiene:repeating units derived from maleic acid = 1:1 (molar ratio), manufactured by PolySciences) 4 parts by mass

[0131] FAM-201 (difunctional acrylamide, manufactured by FUJIFILM Corporation) 1 part by mass

[0132] IRGACURE-OXE02 (oxime ester polymerization initiator, manufactured by BASF) 0.05 parts by mass

[0133] (Formation of the plated layer)

[0134] The above-mentioned composition for forming a layer to be plated was bar-coated on the first surface 1A side of the substrate 1 to a thickness of about 0.30 μm, thereby forming a precursor layer to be plated. Then, after drying at 120° C. for 1 minute, a protective film made of polypropylene with a thickness of 12.00 μm was immediately attached to the surface of the precursor layer to be plated.

[0135] A photomask having an exposure pattern corresponding to the plurality of touch detection electrodes 11 was overlapped on the precursor layer to be plated with the protective film attached thereto, and a high pressure mercury lamp was used to expose the precursor layer at 30 mJ / cm 2 Next, the protective film was peeled off from the surface of the precursor layer to be plated, and the surface was rinsed with a 1 mass % sodium carbonate aqueous solution and alkali developed to obtain a plated layer 31 having a grid-like pattern corresponding to the plurality of touch detection electrodes 11 .

[0136] (Formation of Touch Detection Electrode)

[0137] Omnishield 1573 activator (manufactured by ROHM AND HAAS ELECTRONIC MATERIALS KK) as a Pd catalyst imparting liquid was diluted with pure water to 3.6% by volume, and the pH was adjusted to 4 by 0.1% of chlorocyanic acid, and the substrate 1 formed with the plated layer 31 was immersed at a temperature of 45°C for 5 minutes, and then washed twice with pure water. Next, the substrate 1 was immersed in a 0.8% by volume aqueous solution of a reducing agent CIRCUPOSIT PB Oxide Converter 60C (manufactured by Dow Chemical Company) at a temperature of 30°C for 5 minutes, and then washed twice with pure water, and a Pd catalyst treatment was performed. Next, the substrate 1 treated with Pd catalyst was immersed in an electroless plating solution mixed with 12 volume % of agent M of CIRCUPOSIT4500 (manufactured by ROHM AND HAAS ELECTRONIC MATERIALS KK), 6 volume % of agent A and 10 volume % of agent B at a temperature of 40°C for 50 minutes, and then washed with pure water, thereby forming a plurality of touch detection electrodes 11 covering the plated layer 31 and electrically connected to the plurality of detection electrode connection terminals 12.

[0138] In this way, a touch sensor of Example 1 is obtained. The touch sensor of Example 1 has: 50 touch detection electrodes 11 having an electrode width of 2 mm along the X direction and an electrode length of 100 mm along the Y direction; 50 detection electrode connection terminals 12 connected to the 50 touch detection electrodes 11; 50 peripheral wirings 13 connected to the 50 detection electrode connection terminals 12; and 50 external connection terminals 14 connected to the 50 peripheral wirings 13.

[0139] Furthermore, the line width W1 of the plurality of metal thin wires M constituting the touch detection electrode 11 is 1.50 μm, and the line width W2 of the plurality of peripheral wirings 13 and the distance L2 between the wirings are both 15.00 μm.

[0140] In addition, the plurality of metal fine wires M are observed by an optical microscope and the line widths W1 are randomly measured at a plurality of locations, and the line widths W1 of the plurality of metal fine wires M are calculated by their arithmetic average. The line widths W2 of the plurality of peripheral wirings 13 are also calculated in the same manner as the line widths W1 of the plurality of metal fine wires M. Furthermore, the distances L2 between the wirings at the locations closest to a pair of peripheral wirings 13 are measured for all combinations of a pair of peripheral wirings 13 adjacent to each other, and the distances L2 between the wirings of the plurality of peripheral wirings 13 are calculated by their arithmetic average.

[0141] (Example 2)

[0142] The touch sensor of Example 2 was manufactured in the same manner as in Example 1, except that the line width W2 of the plurality of peripheral wirings 13 and the average value of the distance L2 between the wirings were set to 30.00 μm.

[0143] (Comparative Example 1)

[0144] The touch sensor of Comparative Example 1 was manufactured in the same manner as Example 1, except that a plurality of touch detection electrodes 11, a plurality of detection electrode connection terminals 12, a plurality of peripheral wirings 13 and a plurality of external connection terminals 14 were formed together by a wet plating method through the same method as the process of preparing a composition for forming a plated layer, the process of forming a plated layer 31 and the process of forming a touch detection electrode 11.

[0145] (Comparative Example 2)

[0146] The touch sensor of Example 2 was manufactured in the same manner as in Comparative Example 1, except that the line width W2 of the plurality of peripheral wirings 13 and the average value of the distance L2 between the wirings were set to 30.00 μm.

[0147] The touch sensors of Examples 1 and 2 and Comparative Examples 1 and 2 manufactured in this manner were evaluated for disconnection of peripheral wiring as described below.

[0148] (Evaluation of peripheral wiring disconnection)

[0149] The resistance value between the detection electrode connection terminal 12 and the external connection terminal 14 of each peripheral wiring 13 was measured, and the touch sensor with a resistance value of 1 kΩ or more at one or more locations was determined to be defective. 100 identical touch sensors were manufactured, and the number of defective products was divided by the total number of touch sensors, that is, 100, and the defective product generation rate was calculated and evaluated according to the following criteria. Evaluation A indicates that the defective product generation rate is low and that disconnection of multiple peripheral wirings 13 can be prevented. Evaluations B and C both indicate that there are practical problems with the defective product generation rate.

[0150] A: The defective product rate is less than 2%.

[0151] B: The defective product rate is more than 2% and less than 5%.

[0152] C: The defective product rate exceeds 5%.

[0153] Table 1 shows the evaluation results of Examples 1 and 2 and Comparative Examples 1 and 2.

[0154] In the column of “Formation timing” in Table 1, “Separate formation” means that the touch detection electrodes 11 are formed after forming the detection electrode connection terminals 12 , the peripheral wirings 13 , and the external connection terminals 14 , and “Simultaneous formation” means that they are formed simultaneously.

[0155] [Table 1]

[0156]

[0157] As shown in Table 1, it can be seen that in the touch sensors of Examples 1 and 2, the disconnection evaluation of the peripheral wiring 13 is A, and the disconnection of the plurality of peripheral wirings 13 can be sufficiently prevented. In Examples 1 and 2, the metal layer is patterned by optical lithography, and the plurality of peripheral wirings 13 are formed by wet etching, so it is considered that the peripheral wirings 13 without disconnection can be stably formed.

[0158] On the other hand, in the touch sensor of Comparative Example 1, the disconnection of the peripheral wiring 13 was evaluated as C, and in the touch sensor of Comparative Example 2, the disconnection of the peripheral wiring 13 was evaluated as B. In the touch sensors of Comparative Example 1 and Comparative Example 2, a plurality of peripheral wirings 13 are formed by wet plating, so bubbles generated during plating or impurities mixed in for some reason are arranged in the plated layer 31 corresponding to the peripheral wiring 13, and it is considered that the peripheral wiring 13 is often formed in a disconnected state. In particular, in the touch sensor of Comparative Example 1, the line width W2 of the peripheral wiring 13 is 15.00 μm and is relatively thin, so it is considered that the peripheral wiring 13 is more likely to be disconnected than in Comparative Example 2 where the line width W2 of the peripheral wiring 13 is 30.00 μm.

[0159] The present invention is basically configured as described above. Although the touch sensor of the present invention has been described in detail above, the present invention is not limited to the above-described embodiments, and various improvements or changes can be made without departing from the gist of the present invention.

[0160] Explanation of symbols

[0161] 1-substrate, 1A-first surface, 1B-second surface, 2-first conductive layer, 3-second conductive layer, 11, 21-touch detection electrodes, 12, 22-detection electrode connection terminals, 13, 23-peripheral wiring, 14, 24-external connection terminals, 31-plated layer, 31A-side, L2-distance between wirings, M-metal fine wire, R1-detection area, R2-peripheral area, W1, W2-line width.

Claims

1. A method for manufacturing a touch sensor, comprising: A step of preparing a substrate, the substrate comprising a detection area and a peripheral area arranged around the detection area; forming a metal layer in the peripheral region of the substrate; The step of forming a plurality of detection electrode connection terminals, a plurality of external connection terminals, and a plurality of peripheral wirings, wherein a photosensitive resist is patterned on the surface of the metal layer by photolithography, and the metal layer is wet-etched to form a plurality of detection electrode connection terminals, a plurality of external connection terminals, and a plurality of peripheral wirings connecting the plurality of detection electrode connection terminals and the plurality of external connection terminals to each other; a step of forming a plated layer, the plated layer being formed in the detection region of the substrate and extending so as to cover at least a portion of each of the plurality of detection electrode connection terminals and including a pattern consisting of a plurality of fine lines; and The step of forming a plurality of touch detection electrodes includes forming a plurality of touch detection electrodes electrically connected to the plurality of detection electrode connection terminals on the plated layer by a wet plating method.

2. The method for manufacturing a touch sensor according to claim 1, wherein: The method further includes forming a first protective layer between the step of forming a plurality of detection electrode connection terminals, a plurality of external connection terminals, and a plurality of peripheral wirings and the step of forming a plated layer. The first protective layer covers at least the plurality of peripheral wirings.

3. The method for manufacturing a touch sensor according to claim 2, further comprising: a step of forming a second protective layer that covers the plurality of touch detection electrodes.

4. The method for manufacturing a touch sensor according to claim 3, wherein: The composition of the first protective layer and the composition of the second protective layer are different from each other.

5. The method for manufacturing a touch sensor according to any one of claims 1 to 4, wherein: The plated layer is formed by photolithography.

6. A touch sensor comprising: A substrate including a detection area and a peripheral area disposed around the detection area; A plurality of detection electrode connection terminals are arranged in the peripheral area of ​​the substrate; A plurality of external connection terminals are arranged in the peripheral area of ​​the substrate; a plurality of peripheral wirings arranged in the peripheral region of the substrate and connecting the plurality of detection electrode connection terminals and the plurality of external connection terminals to each other; a plated layer formed in the detection region of the substrate and extending in a manner covering at least a portion of each of the plurality of detection electrode connection terminals, and including a pattern consisting of a plurality of fine lines; and A plurality of touch detection electrodes are disposed on at least a portion of each of the plurality of detection electrode connection terminals and the plated layer, and are electrically connected to the plurality of detection electrode connection terminals.

7. The touch sensor according to claim 6, wherein: The distance between the plurality of peripheral wirings adjacent to each other is 15 μm or less.

8. The touch sensor according to claim 6 or 7, wherein: The plated layer has an organic substance as a main component and contains a palladium catalyst.

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