Touch panel and manufacturing method thereof

Abstract

The present invention discloses a touch panel and a manufacturing method thereof. The touch panel comprises: a substrate having a display area and a peripheral area; a first touch sensing electrode and a second touch sensing electrode, which are arranged in the display area of ​​the substrate; a first peripheral circuit and a second peripheral circuit, which are arranged in the peripheral area of ​​the substrate, wherein the first touch sensing electrode layer comprises a first portion of a patterned first metal nanowire layer, the peripheral circuit comprises a co-etched conductive layer and a second portion of the first metal nanowire layer, the conductive layer and the second portion of the first metal nanowire layer have a common etching surface, and the second touch sensing electrode is formed on an insulating layer and connected to the second peripheral circuit.

Description

Technical Field

[0001] The invention relates to a touch panel and a manufacturing method thereof. Background Art

[0002] Since transparent conductors can have both light transmittance and appropriate conductivity, they can be used in devices related to display panels or touch panels. Generally speaking, transparent conductors can be various metal oxides, such as indium tin oxide (ITO), indium zinc oxide (IZO), cadmium tin oxide (CTO) or aluminum-doped zinc oxide (AZO). However, some properties of these metal oxide films have been challenged, such as insufficient flexibility. In some cases, patterned metal oxide films may also have problems that are easily observed by users. Therefore, a variety of transparent conductors have been developed today, such as transparent conductors made using materials such as nanowires.

[0003] However, when using nanowires to make touch electrodes, there are many problems to be solved in terms of technology and structure between the nanowires and the metal leads in the peripheral area. For example, alignment space needs to be reserved during the bonding process, which makes the product unable to meet the requirements of narrow bezels.

[0004] On the other hand, the integration of touch-sensing products made of nanowires with other optical components is also a focus of attention.

[0005] Therefore, the process of using nanowires to make touch sensing electrodes and the electrode structure must be redesigned according to the material properties to achieve better product performance. Summary of the invention

[0006] Some embodiments of the present invention provide a touch panel manufacturing method that solves the above-mentioned problems, which has the advantages of high manufacturing efficiency, low circuit impedance, and good optical and electrical properties of the display area.

[0007] Some embodiments of the present invention provide a touch panel having a display area and a peripheral area, the touch panel comprising: a substrate; a first touch sensing electrode disposed on a first surface of the substrate and located in the display area, the first touch sensing electrode comprising a first portion of a patterned first metal nanowire layer; a first peripheral circuit and a second peripheral circuit disposed on the first surface of the substrate and located in the peripheral area, the first peripheral circuit being electrically connected to the first touch sensing electrode, the first peripheral circuit and the second peripheral circuit comprising a conductive layer and a second portion of the first metal nanowire layer, the conductive layer and the second portion of the first metal nanowire layer having a common etched surface; an insulating layer covering the first touch sensing electrode and the second peripheral circuit, wherein the insulating layer comprises a conductive through hole disposed corresponding to the second peripheral circuit; and a second touch sensing electrode disposed on the insulating layer, the second touch sensing electrode comprising a patterned second metal nanowire layer, wherein the second touch sensing electrode is electrically connected to the second peripheral circuit through the conductive through hole.

[0008] In some embodiments of the present invention, the second portion of the first metal nanowire layer is formed on the first surface of the substrate, and the conductive layer is formed on the second portion of the metal nanowire layer, or the conductive layer is formed on the first surface of the substrate, and the second portion of the first metal nanowire layer is formed on the upper surface of the conductive layer.

[0009] In some embodiments of the present invention, a primer layer is further included, which is disposed on the first metal nanowire layer and / or the second metal nanowire layer.

[0010] In some embodiments of the present invention, the touch panel has a pair of second peripheral circuits, the insulating layer includes a pair of conductive through-holes arranged corresponding to the second peripheral circuits, the second touch sensing electrode is electrically connected to the pair of second peripheral circuits through the pair of conductive through-holes, and forms a bridge structure on the insulating layer.

[0011] In some embodiments of the present invention, a liquid crystal material layer is further included, which is formed on a second surface of the substrate opposite to the first surface.

[0012] In some embodiments of the present invention, the liquid crystal material layer includes a polarizing liquid crystal layer and / or a phase difference liquid crystal layer.

[0013] Some embodiments of the present invention provide a method for manufacturing a touch panel, comprising: manufacturing a first metal nanowire layer composed of metal nanowires on a first surface of a substrate; manufacturing a conductive layer on the first metal nanowire layer; performing a first patterning step, including: patterning the first metal nanowire layer located in a display area, and simultaneously patterning the conductive layer and the first metal nanowire layer located in a peripheral area to form a first peripheral circuit and a second peripheral circuit; removing the conductive layer located in the display area to expose a first touch sensing electrode formed by patterning the first metal nanowire layer; manufacturing an insulating layer to cover the first touch sensing electrode and the second peripheral circuit, wherein the insulating layer comprises a conductive through hole arranged corresponding to the second peripheral circuit; manufacturing a second touch sensing electrode on the insulating layer, and the second touch sensing electrode is electrically connected to the second peripheral circuit through the conductive through hole.

[0014] In some embodiments of the present invention, fabricating the second touch sensing electrode on the insulating layer includes: fabricating a second metal nanowire layer composed of metal nanowires on the insulating layer; and performing a second patterning step to pattern the second metal nanowire layer to form the second touch sensing electrode.

[0015] In some embodiments of the present invention, removing the conductive layer located in the display area includes removing the conductive layer located in the display area using a first etching solution.

[0016] In some embodiments of the present invention, performing the first patterning step includes etching the conductive layer and the first metal nanowire layer simultaneously using a second etching solution.

[0017] In some embodiments of the present invention, a liquid crystal material layer is further formed on a second surface of the substrate opposite to the first surface, wherein the method of forming the liquid crystal material layer includes coating and printing.

[0018] Some embodiments of the present invention provide a method for manufacturing a touch panel, comprising: manufacturing a conductive layer on a first surface of a substrate; removing the conductive layer located in a display area; manufacturing a first metal nanowire layer composed of metal nanowires on the first surface of the substrate and on the surface of the conductive layer; performing a first patterning step, comprising: patterning the first metal nanowire layer located in the display area to form a first touch sensing electrode, and simultaneously patterning the conductive layer and the first metal nanowire layer located in a peripheral area to form a first peripheral circuit and a second peripheral circuit; manufacturing an insulating layer covering the first touch sensing electrode and the second peripheral circuit, wherein the insulating layer comprises a conductive through hole arranged corresponding to the second peripheral circuit; manufacturing a second touch sensing electrode on the insulating layer, and the second touch sensing electrode is electrically connected to the second peripheral circuit through the conductive through hole.

[0019] In some embodiments of the present invention, forming the second touch sensing electrode on the insulating layer includes: forming a second metal nanowire layer composed of metal nanowires on the insulating layer; and performing a second patterning step to pattern the second metal nanowire layer to form the second touch sensing electrode.

[0020] In some embodiments of the present invention, removing the conductive layer located in the display area includes removing the conductive layer located in the display area using a first etching solution.

[0021] In some embodiments of the present invention, performing the first patterning step includes etching the conductive layer and the first metal nanowire layer simultaneously using a second etching solution.

[0022] According to some embodiments of the present invention, performing a patterning step includes etching the conductive layer and the metal nanowire layer using a second etching solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of a touch panel according to some embodiments of the present invention.

[0024] Figure 2 Schematic diagram of the first step of a method for manufacturing a touch panel according to some embodiments of the present invention.

[0025] Figure 3 Schematic diagram of the second step of the method for manufacturing a touch panel according to some embodiments of the present invention.

[0026] Figure 4 Schematic diagram of the third step of the method for manufacturing a touch panel according to some embodiments of the present invention.

[0027] Figure 4A For along Figure 4 Schematic cross-sectional view of line AA.

[0028] Figure 4B For along Figure 4 A schematic cross-sectional view of line BB.

[0029] Figure 4C For along Figure 4 Schematic cross-sectional view of line CC.

[0030] Figure 5 Schematic diagram of the fourth step of the method for manufacturing a touch panel according to some embodiments of the present invention.

[0031] Figure 5A For along Figure 5 Schematic cross-sectional view of line AA.

[0032] Figure 6Schematic diagram of the fifth step of the method for manufacturing a touch panel according to some embodiments of the present invention.

[0033] Fig. 6A For along Figure 6 Schematic cross-sectional view of line AA.

[0034] Figure 7 Schematic diagram of a touch panel according to some embodiments of the present invention.

[0035] Figure 8 A-8D are schematic diagrams of steps of a method for manufacturing a touch panel according to some embodiments of the present invention.

[0036] Fig. 9 Schematic diagram of a touch panel according to some embodiments of the present invention.

[0037] The accompanying drawings are denoted as follows:

[0038] 110: substrate TE1: first touch sensing electrode

[0039] 120A: conductive layer TE2: second touch sensing electrode

[0040] 120: Peripheral line D1: First direction

[0041] 122: first side wall D2: second direction

[0042] 160: Insulation layer PT1: First peripheral circuit

[0043] 161: Conductive perforation PT2: Second peripheral circuit

[0044] 130B: second anti-etching layer 140A: first metal nanowire layer

[0045] 136: non-conductive region 140B: second metal nanowire layer

[0046] VA: Display area 140: Metal nanowires

[0047] PA: peripheral area 142: second side wall

[0048] 100: Touch panel

[0049] 210: Liquid crystal material layer DETAILED DESCRIPTION

[0050] The following will disclose multiple embodiments of the present invention with drawings. For the purpose of clear description, many practical details will be described together in the following description. However, it should be understood that these practical details should not be used to limit the present invention. That is, in some embodiments of the present invention, these practical details are not necessary. In addition, for the purpose of simplifying the drawings, some conventional structures and components will be shown in the drawings in a simple schematic manner.

[0051] As used herein, "about", "approximately" or "roughly" generally refers to a numerical error or range within 20%, preferably within 10%, and more preferably within 5%. Unless otherwise specified, the numerical values ​​mentioned are considered approximate values, that is, they have an error or range as indicated by "about", "approximately" or "roughly". In addition, the "pattern", "graphic", and "drawing" used herein all have the same or similar meanings, and for the sake of convenience, they may be used interchangeably below, which is hereby explained.

[0052] The embodiment of the present invention provides a touch panel 100, such as Figure 1 As shown, it includes a substrate 110, a peripheral circuit 120, a first touch sensing electrode TE1 composed of a first metal nanowire layer 140A, a second touch sensing electrode TE2 composed of a second metal nanowire layer 140B, and an insulating layer 160 (such as a ) disposed between the first and second touch sensing electrodes TE1 and TE2. Fig. 6A As shown), the first and second touch sensing electrodes TE1 and TE2 are electrically connected to the peripheral circuit 120, and the peripheral circuit 120 can be composed of a conductive layer 120A and a first metal nanowire layer 140A (as shown Fig. 6A The number of the peripheral circuit 120, the first touch sensing electrode TE1 and the second touch sensing electrode TE2 can be one or more, and the numbers shown in the following specific embodiments and drawings are only for explanation and do not limit the present invention.

[0053] See also Figure 1 , the substrate 110 may have a display area VA and a peripheral area PA, the peripheral area PA is disposed on the side of the display area VA, for example, the peripheral area PA may be a frame-shaped area disposed around the display area VA (i.e., covering the right side, left side, top side and bottom side), but in other embodiments, the peripheral area PA may be an L-shaped area disposed on the left side and bottom side of the display area VA. Figure 1 As shown, in this embodiment, there are seven groups of first peripheral circuits PT1 and five groups of second peripheral circuits PT2 on the left and right sides disposed in the peripheral area PA of the substrate 110 ; and the first touch sensing electrodes TE1 or the second touch sensing electrodes TE2 are substantially disposed in the display area VA of the substrate 110 .

[0054] The manufacturing method of the touch panel of the present embodiment may include the following steps: providing a substrate 110; disposing a first metal nanowire layer 140A composed of metal nanowires 140 on the substrate 110; disposing a conductive layer 120A on the first metal nanowire layer 140A; performing a patterning step to form a first touch sensing electrode TE1 and simultaneously forming a peripheral circuit 120. The specific process of the manufacturing method of the touch panel of the present embodiment is: first, referring to Figure 2 A substrate 110 is provided. In some embodiments of the present invention, the substrate 110 is ideally a transparent substrate. Specifically, it can be a rigid transparent substrate or a flexible transparent substrate. Its material can be selected from transparent materials such as glass, acrylic (polymethylmethacrylate; PMMA), polyvinyl chloride (polyvinyl Chloride; PVC), polypropylene (polypropylene; PP), polyethylene terephthalate (polyethylene terephthalate; PET), polyethylene naphthalate (polyethylene naphthalate; PEN), polycarbonate (polycarbonate; PC), polystyrene (polystyrene; PS), etc.

[0055] Next, refer to Figure 2 , a first metal nanowire layer 140A and a conductive layer 120A are fabricated on the substrate 110, and the first metal nanowire layer 140A may be composed of at least metal nanowires 140. In the present embodiment, the first metal nanowire layer 140A is specifically fabricated by coating a dispersion or slurry (ink) containing metal nanowires 140 on a first surface (such as the upper surface) of the substrate 110, and drying the dispersion or slurry so that the metal nanowires 140 are coated on the surface of the substrate 110; in other words, the metal nanowires 140 are formed into a first metal nanowire layer 140A disposed on the substrate 110 due to the above drying and curing steps. The substrate 110 may be defined with a display area VA and a peripheral area PA (such as Figure 1 ), the peripheral area PA is arranged on the side of the display area VA; and the first metal nanowire layer 140A may include a first portion formed in the display area VA and a second portion formed in the peripheral area PA. In more detail, in the display area VA, the first portion of the first metal nanowire layer 140A may be directly formed on the surface of the substrate 110; and in the peripheral area PA, the second portion of the first metal nanowire layer 140A may also be directly formed on the surface of the substrate 110.

[0056] In an embodiment of the present invention, the dispersion liquid having the metal nanowires 140 may be a solvent, such as water, alcohol, ketone, ether, hydrocarbon or aromatic solvent (benzene, toluene, xylene, etc.); the dispersion liquid may also contain additives, surfactants or adhesives, such as carboxymethyl cellulose (CMC), 2-hydroxyethyl cellulose (HEC), hydroxypropyl methylcellulose (HPMC), sulfonates, sulfates, disulfonates, sulfosuccinates, phosphates or fluorine-containing surfactants, etc. The metal nanowire layer may be composed of a silver nanowire layer, a gold nanowire layer or a copper nanowire layer. In more detail, the "metal nanowire" used herein is "nanowires" is a collective noun, which refers to a collection of metal wires comprising multiple elemental metals, metal alloys or metal compounds (including metal oxides), wherein the number of metal nanowires contained therein does not affect the scope of protection claimed by the present invention; and at least one cross-sectional dimension (i.e., the diameter of the cross section) of a single metal nanowire is less than 500nm, preferably less than 100nm, and more preferably less than 50nm; and the metal nanostructures referred to as "wires" in the present invention mainly have a high aspect ratio, for example, between 10 and 100,000, and more specifically, the aspect ratio (length: cross-sectional diameter) of the metal nanowires can be greater than 10, preferably greater than 50, and more preferably greater than 100; the metal nanowires can be any metal, including (but not limited to) silver, gold, copper, nickel and gold-plated silver. Other terms, such as silk, fiber, tube, etc., if they also have the above-mentioned dimensions and high aspect ratios, are also within the scope of the present invention.

[0057] The dispersion or slurry containing the metal nanowires 140 can be formed on the surface of the substrate 110 in any manner, such as but not limited to screen printing, nozzle coating, roller coating and other processes; in one embodiment, the dispersion or slurry containing the metal nanowires 140 can be coated on the surface of the continuously supplied substrate 110 by a roll-to-roll process. After the above-mentioned curing / drying steps, the solvent and other substances are volatilized, and the metal nanowires 140 are randomly distributed on the surface of the substrate 110; preferably, the metal nanowires 140 are fixed on the surface of the substrate 110 without falling off to form the first metal nanowire layer 140A, and the metal nanowires 140 can contact each other to provide a continuous current path, thereby forming a conductive network.

[0058] In some embodiments of the present invention, the metal nanowires 140 may be silver nanowires or silver nanofibers, which may have an average diameter of about 20 to 100 nanometers and an average length of about 20 to 100 micrometers, preferably an average diameter of about 20 to 70 nanometers and an average length of about 20 to 70 micrometers (i.e., an aspect ratio of 1000). In some embodiments, the diameter of the metal nanowires 140 may be between 70 nanometers and 80 nanometers, and the length may be about 8 micrometers.

[0059] In one embodiment, an overcoat (not shown) may be disposed on the first metal nanowire layer 140A, and after curing, the overcoat and the first metal nanowire layer 140A form a composite structure layer. In one embodiment, a suitable polymer or a mixture thereof may be formed on the first metal nanowire layer 140A by a coating method, and the polymer may penetrate between the metal nanowires 140 to form a filler, and a curing step may be performed to form an overcoat. In other words, the metal nanowires 140 may be considered to be embedded in the overcoat. In a specific embodiment, the curing step may be: the polymer or the mixture thereof may be formed into an overcoat on the first metal nanowire layer 140A by heating and baking (at a temperature of about 60° C. to about 150° C.). The present invention does not limit the physical structure between the overcoat and the first metal nanowire layer 140A. For example, the overcoat and the first metal nanowire layer 140A may be a stack of two layers, or the overcoat and the first metal nanowire layer 140A may be combined to form a composite layer. Preferably, the metal nanowires 140 are embedded in the base coating to form a composite structure and are patterned in a subsequent process.

[0060] The above polymers can preferably give the metal nanowires 140 certain specific chemical, mechanical and optical properties, such as providing adhesion between the metal nanowires 140 and the substrate 110, or better physical mechanical strength, so the base coating can also be called a matrix. On the other hand, using certain specific polymers to make the base coating can give the metal nanowires 140 additional surface protection against scratches and wear. Using materials such as polyacrylate, epoxy resin, polyurethane, polysilane, polysiloxane, poly(silicon-acrylic acid) and the like can give the metal nanowires 140 a higher surface strength to improve scratch resistance. Furthermore, the above polymers can be added with crosslinking agents, polymerization inhibitors, stabilizers (such as but not limited to antioxidants, UV stabilizers), surfactants or the like or mixtures thereof to improve the UV resistance of the composite structure CS or achieve a longer shelf life.

[0061] The specific method of the conductive layer 120A in this embodiment is: a metal material is formed on the first metal nanowire layer 140A by an appropriate process. For example, but not limited to, a metal with good conductivity (such as a single layer of silver, copper, or a multi-layer material, such as molybdenum / aluminum / molybdenum, copper / nickel, titanium / aluminum / titanium, molybdenum / chromium) is formed on the first metal nanowire layer 140A. Similar to the first metal nanowire layer 140A, the conductive layer 120A may include a first portion formed in the display area VA and a second portion formed in the peripheral area PA, and the first portion of the conductive layer 120A is removed in a subsequent process, and the second portion of the conductive layer 120A and the second portion of the first metal nanowire layer 140A are patterned in a subsequent process to form the peripheral circuit 120.

[0062] Then, a first patterning step is performed, which mainly patterns the conductive layer 120A and the first metal nanowire layer 140A to form a pattern of the first touch sensing electrode TE1, and simultaneously patterns the conductive layer 120A and the first metal nanowire layer 140A in the peripheral area PA to form the peripheral circuit 120. Figure 3 The present embodiment may specifically include the following steps: firstly, a photosensitive material (such as a photoresist) is exposed / developed (i.e., a well-known lithography process) to define a pattern of the first touch sensing electrode TE1 located in the display area VA and a pattern of the peripheral circuit 120 located in the peripheral area PA; then, etching is performed to form a pattern of the first touch sensing electrode TE1 composed of the first metal nanowire layer 140A (i.e., the first part of the first metal nanowire layer 140A) on the display area VA; and a peripheral circuit 120 composed of the first metal nanowire layer 140A (i.e., the second part of the first metal nanowire layer 140A) and the conductive layer 120A (i.e., the second part of the conductive layer 120A) is formed on the peripheral area PA.

[0063] In one embodiment, an etching solution (i.e., a first etching solution) capable of etching the first metal nanowire layer 140A and the conductive layer 120A simultaneously is used to manufacture the first touch sensing electrode TE1 and the peripheral circuit 120 in the same process. Therefore, the connection between the first touch sensing electrode TE1 in the display area VA and the peripheral circuit 120 in the peripheral area PA can be completed with a minimum number of alignments (e.g., one time). Therefore, the low yield rate caused by multiple alignments in the conventional method can be avoided, and the alignment tolerance required for the alignment process can be saved, so that the width of the peripheral circuit 120 can be reduced as much as possible to meet the narrow frame requirement of the display.

[0064] According to a specific embodiment, when the first metal nanowire layer 140A is a nanosilver layer and the conductive layer 120A is a copper layer, the first etching solution can be used to etch copper and silver. For example, the main components of the etching solution are HNO3 (at a ratio of 5% to 15%) and H3PO4 (at a ratio of 55% to 70%), so as to remove the copper material and the silver material in the same process. In another specific embodiment, an additive such as an etching selectivity adjuster can be added to the main components of the etching solution to adjust the etching rates of copper and silver; for example, 5% to 10% of Benzotriazole (BTA) can be added to the main components of HNO3 (at a ratio of 5% to 15%) and H3PO4 (at a ratio of 55% to 70%) to solve the problem of copper over-etching.

[0065] Then, a second patterning step is performed, which mainly performs patterning on the conductive layer 120A to remove the metal material located in the display area VA and expose the first touch sensing electrode TE1 formed by the patterning of the first metal nanowire layer 140A. This embodiment may specifically include the following steps: firstly, a photosensitive material (such as a photoresist) is exposed / developed (i.e., a well-known yellow light process) to define a pattern to expose the first portion of the conductive layer 120A located in the display area VA; then, etching is performed to remove the first portion of the conductive layer 120A located in the display area VA, so that the first metal nanowire layer 140A is exposed on the display area VA (at this time, the first metal nanowire layer 140A already has a pattern, i.e., the first touch sensing electrode TE1).

[0066] In the above etching step, for example, when the first metal nanowire layer 140A is a nanosilver layer and the conductive layer 120A is a copper layer, the second etching solution can be used to etch copper, and the second etching solution has a significantly lower corrosion rate for nanosilver to prevent the nanosilver layer from being affected by the copper etching solution. In a specific embodiment, the main components of the copper etching solution are CH3COOH and NH4OH, and the etching rate of the etching solution components for nanosilver wires is much lower than the etching rate for copper (for example, the etching rate ratio of the two is 1:100 to 1:10000). In one embodiment, after being treated with the above etching solution, the resistance value of the first metal nanowire layer 140A changes by less than 10%.

[0067] In a variation embodiment, the conductive layer 120A located in the display area VA may be removed first; then a second patterning step is performed, which mainly patterns the first metal nanowire layer 140A located in the display area VA to form the first touch sensing electrode TE1, and simultaneously patterns the conductive layer 120A and the first metal nanowire layer 140A located in the peripheral area PA to form the peripheral circuit 120.

[0068] Figure 4 That is, the structure after the patterning of the above two steps is shown, and the first touch sensing electrode TE1 composed of the first metal nanowire layer 140A (i.e., the first part of the first metal nanowire layer 140A) is provided on the display area VA; and the peripheral circuit 120 composed of the first metal nanowire layer 140A (i.e., the second part of the first metal nanowire layer 140A) and the conductive layer 120A (i.e., the second part of the conductive layer 120A) is formed on the peripheral area PA. In addition, please also refer to Figure 4 , Figure 4A and Figure 4B The peripheral circuit 120 may include a first peripheral circuit PT1 and a second peripheral circuit PT2. The first touch sensing electrode TE1 is electrically connected to the first peripheral circuit PT1, and the second peripheral circuit PT2 is connected to the second touch sensing electrode TE2 formed in a subsequent step. The second peripheral circuit PT2 is not limited to both sides of the second touch sensing electrode TE2, and may also be formed only on one side of the second touch sensing electrode TE2.

[0069] Next, an insulating layer 160 is formed, and a conductive through hole 161 is formed in the insulating layer 160. Figure 5 In one embodiment, an insulating material such as SiO2 may be used to cover the first metal nanowire layer 140A and the conductive layer 120A; in other words, the first touch sensing electrode TE1 in the display area VA and the peripheral circuit 120 (including the first and second peripheral circuits PT1 / PT2) in the peripheral area PA are both covered with an insulating layer 160. In one embodiment, the insulating layer 160 may only cover the first touch sensing electrode TE1 and the second peripheral circuit PT2.

[0070] The material of the insulating layer 160 can be completely or partially filled into the gaps etched in the first metal nanowire layer 140A or the conductive layer 120A. In addition, the insulating layer 160 can be made into conductive vias 161 by using a yellow light process or a laser process. The conductive vias 161 correspond to a portion of the peripheral circuit 120, so that the electrode structure made later can be connected to the peripheral circuit 120 through the conductive vias 161. Figure 5AAs shown, the conductive through hole 161 corresponds to the second peripheral circuit PT2 and exposes the second peripheral circuit PT2. The conductive through hole 161 is located approximately at the junction of the display area VA and the peripheral area PA, and its position can be adjusted according to specific needs.

[0071] Next, a second touch sensing electrode TE2 is fabricated on the insulating layer 160, and the second touch sensing electrode TE2 is connected to the corresponding peripheral circuit 120. Specifically, this step may include: fabricating a second metal nanowire layer 140B on the insulating layer 160; patterning the second metal nanowire layer 140B to form the second touch sensing electrode TE2. The aforementioned steps of fabricating the nanowire layer and patterning can all refer to the above-mentioned embodiments, and will not be repeated here. In addition, the material of the second metal nanowire layer 140B can be fully or partially filled into the conductive through-hole 161, so that the second touch sensing electrode TE2 formed after patterning the second metal nanowire layer 140B is connected to the peripheral circuit 120 disposed on the substrate 110. In one embodiment, nitric acid can be used as an etching solution to pattern the second metal nanowire layer 140B.

[0072] Please refer to Fig. 6A , the second touch sensing electrode TE2 can be connected to the second peripheral circuit PT2 disposed on the substrate 110 through the structure of the conductive through-hole 161. In the present embodiment, a single second touch sensing electrode TE2 corresponds to a pair or a group of second peripheral circuits PT2; correspondingly, the insulating layer 160 includes a pair of conductive through-holes 161 disposed corresponding to the pair of second peripheral circuits PT2, and the single second touch sensing electrode TE2 is electrically connected to the pair of second peripheral circuits PT2 through the pair of conductive through-holes 161, and the second touch sensing electrode TE2 forms a bridge structure on the insulating layer 160; in other words, the two ends of the bridge structure are respectively connected to the pair of second peripheral circuits PT2.

[0073] At this point, the touch panel 100 of the embodiment of the present invention is completed. Figure 6The touch panel 100 of the embodiment of the present invention comprises a substrate 110, a peripheral circuit 120 composed of a conductive layer 120A and a first metal nanowire layer 140A, a first touch sensing electrode TE1 composed of the first metal nanowire layer 140A, a second touch sensing electrode TE2 composed of a second metal nanowire layer 140B, and an insulating layer 160 disposed between the first touch sensing electrode TE1 and the second touch sensing electrode TE2, the first touch sensing electrode TE1 and the second touch sensing electrode TE2 can be electrically connected to the peripheral circuit 120, and the first metal nanowire layer 140A and / or the second metal nanowire layer 140B include metal nanowires 140. In addition, the conductive layer 120A and the first metal nanowire layer 140A are subjected to a co-etching step to simultaneously (meaning in the same etching step) form the first touch sensing electrode TE1 and the peripheral circuit 120 disposed on the upper surface of the substrate.

[0074] In detail, in some embodiments of the present invention, the peripheral circuit 120 may include a first peripheral circuit PT1 / PT2 and a second peripheral circuit PT1 / PT2 connecting electrodes of different axes. In terms of structure, the first peripheral circuit PT1 / PT2 is a composite structure layer composed of two patterned conductive structures, including a conductive layer 120A and a first metal nanowire layer 140A located between the conductive layer 120A and the substrate 110. The conductive layer 120A and the first metal nanowire layer 140A (i.e., the second portion of the first metal nanowire layer 140A) constituting the peripheral circuit 120 have a common etch-surface. The first touch sensing electrode TE1 is formed after the first metal nanowire layer 140A is patterned, that is, the first metal nanowire layer 140A forms the first touch sensing electrode TE1 in the display area VA, and forms the lower structure of the peripheral circuit 120 in the peripheral area PA. Therefore, by virtue of the conductivity of the first metal nanowire layer 140A, the first touch sensing electrode TE1 can be electrically connected to the peripheral circuit 120 to transmit signals. In addition, the first metal nanowire layer 140A and the second metal nanowire layer 140B can be electrically isolated from each other by the insulating layer 160, and the signals transmitted by the first touch sensing electrodes TE1 and the second touch sensing electrodes TE2 formed after patterning can not affect each other. For example, the first touch sensing electrodes TE1 arranged along the first direction D1 can be used to transmit external control signals, and the second touch sensing electrodes TE2 arranged along the second direction D2 can be used to transmit touch sensing signals.

[0075] Please refer to Figure 4 and Figure 4CAs shown, in the peripheral area PA, there is a non-conductive region 136 (here, the second peripheral line PT2 is used as an example) between adjacent peripheral lines 120 to electrically block the adjacent peripheral lines 120 and avoid short circuit. That is, there is a non-conductive region 136 between the first side walls 122 of adjacent conductive layers 120A, and a non-conductive region 136 is also formed between the second side walls 142 of adjacent metal nanowire layers 140A. In this embodiment, the non-conductive region 136 is a gap to isolate the adjacent peripheral lines 120. In one embodiment, the above-mentioned gap can be made by the aforementioned etching method, so the first side wall 122 and the second side wall 142 are a common etching surface, that is, the first side wall 122 and the second side wall 142 are formed in the same etching step using the same etching solution; or the first side wall 122 can be etched out first, and then the second side wall 142 can be etched out. In one embodiment, the second sidewall 142 of the metal nanowire layer 140A will not have the metal nanowires thereon due to the above-mentioned etching step; furthermore, the conductive layer 120A and the metal nanowire layer 140A will have the same or similar patterns and sizes, such as both being long straight patterns, and the same or similar widths.

[0076] Similarly, in the display area VA, a non-conductive region 136 is provided between adjacent first touch sensing electrodes TE1 to electrically block adjacent first touch sensing electrodes TE1 and thus avoid short circuit. A non-conductive region 136 is also provided between adjacent second touch sensing electrodes TE2. In one embodiment, the above-mentioned etching method can be used to form the gap between adjacent first touch sensing electrodes TE1 or the gap between adjacent second touch sensing electrodes TE2.

[0077] In this embodiment, the first touch sensing electrodes TE1 and the second touch sensing electrodes TE2 are arranged in a staggered arrangement. For example, the first touch sensing electrodes TE1 are long strip electrodes extending along the first direction D1, and the second touch sensing electrodes TE2 are long strip electrodes extending along the second direction D2, forming a staggered structure with each other. In other embodiments, the first touch sensing electrodes TE1 and / or the second touch sensing electrodes TE2 may have an appropriate shape, such as a quadrilateral or hexagonal structure connected in series, and the embodiments herein should not limit the scope of the present invention.

[0078] In the present embodiment, the first touch sensing electrodes TE1 and / or the second touch sensing electrodes TE2 of the display area VA preferably have electrical conductivity and light transmittance. Therefore, the nanowire layer used to make the first touch sensing electrodes TE1 and / or the second touch sensing electrodes TE2 preferably has the following characteristics: the light transmittance of visible light (e.g., wavelength between about 400nm-700nm) may be greater than about 80%, and the surface resistivity is between about 10 and 1000 ohm / square; preferably, the light transmittance of the nanowire layer of visible light (e.g., wavelength between about 400nm-700nm) is greater than about 85%, and the surface resistivity is between about 50 and 500 ohm / square.

[0079] In one embodiment, the touch panel 100 completed above can be further combined with the following process. Figure 7 , a liquid crystal material layer 210 may be formed on the second surface (such as the lower surface) of the substrate 110 relative to the above-mentioned touch electrode. In one embodiment, the touch panel 100 completed above may integrate the liquid crystal material layer 210 to form a touch panel with optical functions. For example, the liquid crystal material layer 210 may be used as an optical functional layer that provides a polarization function (so it can also be called a polarizing liquid crystal layer). This embodiment can form a touch panel with a polarization function. Alternatively, two layers of liquid crystal material layers 210 may be formed, one providing a polarization function (so it can also be called a polarizing liquid crystal layer) and the other providing a function of adjusting the optical phase difference (so it can also be called a phase difference liquid crystal layer). They can be integrated into a composite optical functional layer to simultaneously provide touch sensing, polarization and phase difference adjustment functions.

[0080] In one embodiment, the polarized liquid crystal layer is formed by directly coating a composition containing polymerizable liquid crystal on the second surface of the substrate and curing it. The composition of polymerizable liquid crystal may include a reactive liquid crystal compound and a dichroic dye. When the reactive liquid crystal compound is polymerized by reaction (light irradiation or heat irradiation), it can maintain the liquid crystal configuration and form a polymer network structure, while the dichroic dye can provide polarized properties.

[0081] The phase difference liquid crystal layer of this embodiment is first formed with a photo-alignment material on the polarizing layer liquid crystal to form a photo-alignment layer with two alignment directions, and then a composition containing polymerizable liquid crystal is coated on the photo-alignment layer, and then formed after curing.

[0082] The coating method used in making the polarized liquid crystal layer and the phase difference liquid crystal layer may include slit coating, blade coating, gravure coating, rod coating, roller coating, spin coating, spray coating, screen printing, gravure printing, lithography, dispensing printing, etc. In addition, the curing method used in making the polarized liquid crystal layer and the phase difference liquid crystal layer may include thermal curing or photocuring. In one embodiment, a roll-to-roll process may be used to perform the above-mentioned coating and curing steps. It is additionally noted that in actual design, the polarized liquid crystal layer can be designed as a plurality of stacked structures in order to meet the required polarization value, and the phase difference liquid crystal layer can be designed as a plurality of stacked structures in order to meet the required phase difference value, which is not limited by the present invention.

[0083] The touch panel of this embodiment can provide a polarization function after integrating the polarized liquid crystal layer, and can further provide better image visibility after integrating the phase difference liquid crystal layer. The whole is integrated on the same substrate to form an integrated design. In this way, when the touch panel of this embodiment is applied to an electronic device with a display function, it can effectively achieve a thinning effect. It is worth mentioning that in this embodiment, the production of the touch panel is completed first, and then the polarized liquid crystal layer and / or the phase difference liquid crystal layer are formed on the side of the touch panel substrate where the touch sensing electrode is not set. In this way, it can avoid damage to components (such as liquid crystal layer) caused by environmental factors such as high temperature, strong acid, and strong alkali in the touch sensing electrode process.

[0084] Another method for manufacturing a touch panel is provided in an embodiment of the present invention, which differs from the first manufacturing method described above mainly in that: in this embodiment, a conductive layer 120A is first manufactured in the peripheral area PA; a first metal nanowire layer 140A is then manufactured, and then a patterning step is performed according to the method described above to form the first touch sensing electrodes TE1 and the peripheral circuits 120; an insulating layer 160 is then manufactured; and finally, the second touch sensing electrodes TE2 are manufactured.

[0085] The specific practices can be exemplified as follows: Figure 8 A, firstly, a conductive layer 120A is formed on a surface (such as the upper surface) of the substrate 110; then, the conductive layer 120A located in the display area VA is removed by an etching process, and the remaining conductive layer 120A is approximately located in the peripheral area PA. The above is the first patterning process (such as Figure 8 B). Next, a first metal nanowire layer 140A is formed in the peripheral area PA and the display area VA. The first portion of the first metal nanowire layer 140A is directly formed on the surface of the substrate 110, and the second portion of the first metal nanowire layer 140A covers the conductive layer 120A (such as Figure 8C); then the second patterning process is performed by a co-etching process. In the patterning step, the first metal nanowire layer 140A located on the display area VA is etched to form the first touch sensing electrode TE1; the conductive layer 120A located on the peripheral area PA is also etched and patterned with the metal nanowire layer 140A to form the peripheral circuit 120 (such as Figure 8 D). Next, the insulating layer 160 and the second touch sensing electrode TE2 are manufactured; the specific implementation methods of these two steps are similar to the above-mentioned embodiment and will not be described in detail herein.

[0086] Fig. 9 That is based on Figure 8 Schematic diagram of a touch panel manufactured by the manufacturing method of (A)-(D). The specific content of this embodiment can be referred to the above, and will not be repeated here. Fig. 6A ,like Fig. 9 In the structure shown, the peripheral circuit 120 located in the peripheral area PA is a double-layer structure (based on the substrate 110) with a first metal nanowire layer 140A on the top and a conductive layer 120A on the bottom. That is to say, in this structure, even if the aforementioned base coating is used to protect the metal nanowire 140, the metal nanowire 140 and the conductive layer 120A are still in direct contact, so there is a lower contact impedance between the two, which can improve the loss and distortion of the transmitted touch signal.

[0087] Similar to the above-mentioned embodiment, the liquid crystal material layer 210 may be formed on another surface (such as the lower surface) of the substrate 110 , which will not be described in detail herein.

[0088] In one embodiment, the metal nanowires 140 formed above may be further post-processed to improve their conductivity, and the post-processing may include a process step such as heating, plasma, corona discharge, UV ozone or pressure. For example, after the step of curing to form the first and second metal nanowire layers 140A and 140B, a roller may be used to apply pressure thereon. In one embodiment, a pressure of 50 to 3400 psi may be applied to the metal nanowire layer by one or more rollers, preferably a pressure of 100 to 1000 psi, 200 to 800 psi or 300 to 500 psi may be applied. In some embodiments, heating and pressure post-treatment can be performed simultaneously; in detail, the formed metal nanowire 140 can be subjected to pressure and heating at the same time through one or more rollers as described above, for example, the pressure applied by the roller is 10 to 500 psi, preferably 40 to 100 psi; and the roller is heated to between about 70°C and 200°C, preferably between about 100°C and 175°C, which can improve the conductivity of the first and second metal nanowire layers 140A and 140B. In some embodiments, the metal nanowire 140 is preferably exposed to a reducing agent for post-treatment, for example, the metal nanowire 140 composed of nano silver wires is preferably exposed to a silver reducing agent for post-treatment, and the silver reducing agent includes borohydride, such as sodium borohydride; boron nitrogen compound, such as dimethylamino borane (DMAB); or gas reducing agent, such as hydrogen (H2). The exposure time is about 10 seconds to about 30 minutes, preferably about 1 minute to about 10 minutes. The above-mentioned step of applying pressure can be implemented in appropriate steps according to actual needs.

[0089] The structures, materials, and processes of different embodiments of the present invention may be referenced to each other and are not limited to the above-mentioned specific implementation modes.

[0090] In some embodiments of the present invention, the peripheral metal layer plating process applied to the dual-axis touch sensing electrode can be reduced to a single process, that is, the first and second touch sensing electrodes above and below the insulating layer can be connected, thereby achieving a simplified process.

[0091] In some embodiments of the present invention, the initial process can start from a metal nanowire layer or a metal layer (ie, a conductive layer) as required, so the process is flexible.

[0092] In some embodiments of the present invention, the conductive layer in the peripheral area can directly contact the metal nanowire layer to form a peripheral circuit. Therefore, overall, the metal nanowires in the metal nanowire layer and the peripheral circuit will form a direct contact and low-impedance signal transmission path, which is used to transmit control signals and touch sensing signals between the touch sensing electrodes and the external controller. Due to its low impedance characteristics, it actually helps to reduce the loss of signal transmission, thereby solving the problem of excessively high contact impedance in traditional structures.

[0093] In some implementations of the present invention, a low-impedance peripheral conductive circuit may be formed to enhance the transmission capability of the touch signal, thereby reducing the loss and distortion of the transmitted touch signal.

[0094] In some embodiments of the present invention, the composite structure layer of the peripheral circuit can be formed in a single etching process, so when applied to the manufacture of a touch panel, the patterning process of the peripheral circuit can be simplified, thereby achieving the effects of simple process, rapidity and low manufacturing cost.

[0095] In some embodiments of the present invention, the composite structure layer of the peripheral circuit can be formed in a single etching process, so the number of alignments required in the process can be reduced, thereby avoiding errors in the alignment step and improving the process yield.

[0096] In some embodiments of the present invention, the composite structure layer of the peripheral circuit can be formed in a single etching process, thereby saving the alignment error space reserved in the process, and thus effectively reducing the width of the peripheral area.

[0097] In some embodiments of the present invention, the optical functional layer is fabricated on the other side of the substrate (opposite to the touch sensing electrode), so as to form a highly integrated product having both touch function and optical function.

[0098] In some embodiments of the present invention, the process can be combined with roll-to-roll production technology to continuously and in large batches manufacture touch panels with single-sided / double-sided electrode structures.

Claims

1. A touch panel having a display area and a peripheral area, characterized in that: Include: a substrate; a first touch sensing electrode disposed on a first surface of the substrate and located in the display area, the first touch sensing electrode comprising a first portion of a patterned first metal nanowire layer; A first peripheral circuit and a second peripheral circuit are disposed on the first surface of the substrate and located in the peripheral area, and the first peripheral circuit is electrically connected to the first touch sensing electrode, and the first peripheral circuit and the second peripheral circuit include a conductive layer and a second portion of the first metal nanowire layer, and the conductive layer and the second portion of the first metal nanowire layer have a common etching surface; an insulating layer covering the first touch sensing electrode and the second peripheral circuit, wherein the insulating layer comprises a conductive through hole arranged corresponding to the second peripheral circuit; as well as a second touch sensing electrode disposed on the insulating layer, the second touch sensing electrode comprising a patterned second metal nanowire layer, wherein the second touch sensing electrode is electrically connected to the second peripheral circuit through the conductive through-hole; The touch panel has a pair of second peripheral circuits, the insulating layer includes a pair of conductive through-holes corresponding to the second peripheral circuits, the second touch sensing electrode is electrically connected to the pair of second peripheral circuits through the pair of conductive through-holes, and forms a bridge structure on the insulating layer.

2. The touch panel according to claim 1, wherein: The second portion of the first metal nanowire layer is formed on the first surface of the substrate, and the conductive layer is formed on the second portion of the metal nanowire layer, or the conductive layer is formed on the first surface of the substrate, and the second portion of the first metal nanowire layer is formed on the upper surface of the conductive layer.

3. The touch panel according to claim 1, wherein: The method further includes a base coating layer disposed on the first metal nanowire layer and / or the second metal nanowire layer.

4. The touch panel according to claim 1, wherein: The invention further comprises a liquid crystal material layer formed on a second surface of the substrate opposite to the first surface.

5. The touch panel according to claim 4, wherein: The liquid crystal material layer includes a polarized liquid crystal layer and / or a phase difference liquid crystal layer.

6. A method for manufacturing a touch panel, characterized in that: The touch panel has a display area and a peripheral area. The manufacturing method of the touch panel includes: Fabricating a first metal nanowire layer composed of metal nanowires on a first surface of a substrate; Fabricating a conductive layer on the first metal nanowire layer; Performing a first patterning step, including: patterning the first metal nanowire layer located in the display area, and simultaneously patterning the conductive layer and the first metal nanowire layer located in the peripheral area to form a first peripheral circuit and a second peripheral circuit; Removing the conductive layer located in the display area to expose a first touch sensing electrode formed by patterning the first metal nanowire layer; Making an insulating layer to cover the first touch sensing electrode and the second peripheral circuit, wherein the insulating layer comprises a conductive through hole arranged corresponding to the second peripheral circuit; and A second touch sensing electrode is fabricated on the insulating layer, and the second touch sensing electrode is electrically connected to the second peripheral circuit through the conductive through-hole.

7. The method for manufacturing a touch panel according to claim 6, wherein: The method of manufacturing the second touch sensing electrode on the insulating layer includes: Fabricating a second metal nanowire layer composed of metal nanowires on the insulating layer; and A second patterning step is performed to pattern the second metal nanowire layer to form the second touch sensing electrode.

8. The method for manufacturing a touch panel according to claim 6, wherein: The first patterning step includes using a first etching solution to simultaneously etch the conductive layer and the first metal nanowire layer.

9. The method for manufacturing a touch panel according to claim 8, wherein: The removing of the conductive layer located in the display area includes removing the conductive layer located in the display area by using a second etching solution.

10. The method for manufacturing a touch panel according to claim 6, wherein: The touch panel has a pair of second peripheral circuits, the insulating layer includes a pair of conductive through-holes corresponding to the second peripheral circuits, the second touch sensing electrode is electrically connected to the second peripheral circuits through the pair of conductive through-holes, and forms a bridge structure on the insulating layer.

11. The method for manufacturing a touch panel according to claim 6, wherein: Also includes: A liquid crystal material layer is formed on a second surface of the substrate opposite to the first surface, wherein the method of forming the liquid crystal material layer includes coating and printing.

12. The method for manufacturing a touch panel according to claim 11, wherein: The liquid crystal material layer includes a polarized liquid crystal layer and / or a phase difference liquid crystal layer.

13. A method for manufacturing a touch panel, characterized in that: The touch panel has a display area and a peripheral area. The manufacturing method of the touch panel includes: Fabricating a conductive layer on a first surface of a substrate; removing the conductive layer located in the display area; Fabricating a first metal nanowire layer composed of metal nanowires on the first surface of the substrate and on the surface of the conductive layer; Performing a first patterning step, including: patterning the first metal nanowire layer located in the display area to form a first touch sensing electrode, and simultaneously patterning the conductive layer and the first metal nanowire layer located in the peripheral area to form a first peripheral circuit and a second peripheral circuit; Making an insulating layer to cover the first touch sensing electrode and the second peripheral circuit, wherein the insulating layer comprises a conductive through hole arranged corresponding to the second peripheral circuit; and A second touch sensing electrode is fabricated on the insulating layer, and the second touch sensing electrode is electrically connected to the second peripheral circuit through the conductive through-hole.

14. The method for manufacturing a touch panel according to claim 13, wherein: The method of manufacturing the second touch sensing electrode on the insulating layer includes: Fabricating a second metal nanowire layer composed of metal nanowires on the insulating layer; and A second patterning step is performed to pattern the second metal nanowire layer to form the second touch sensing electrode.

15. The method for manufacturing a touch panel according to claim 13, wherein: The removing of the conductive layer in the display area includes removing the conductive layer in the display area by using a first etching solution.

16. The method for manufacturing a touch panel according to claim 15, wherein: The first patterning step includes using a second etching solution to simultaneously etch the conductive layer and the first metal nanowire layer.

17. The method for manufacturing a touch panel according to claim 13, wherein: The touch panel has a pair of second peripheral circuits, the insulating layer includes a pair of conductive through-holes corresponding to the second peripheral circuits, the second touch sensing electrode is electrically connected to the second peripheral circuits through the pair of conductive through-holes, and forms a bridge structure on the insulating layer.

18. The method for manufacturing a touch panel according to claim 13, wherein: Also includes: A liquid crystal material layer is formed on a second surface of the substrate opposite to the first surface, wherein the method of forming the liquid crystal material layer includes coating and printing.

19. The method for manufacturing a touch panel according to claim 18, wherein: The liquid crystal material layer includes a polarized liquid crystal layer and / or a phase difference liquid crystal layer.

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