Touch panel, method for manufacturing touch panel and device thereof

Abstract

A touch panel and a manufacturing method thereof. The peripheral leads in the touch panel include a conductive nanostructure and a film layer applied to the conductive nanostructure. The interface between the conductive nanostructure and the film layer substantially has a coating structure.

Description

Technical Field

[0001] The invention relates to a touch panel, a method for manufacturing the touch panel and a device comprising the touch panel. Background Art

[0002] In recent years, transparent conductors can allow light to pass through and provide appropriate conductivity at the same time, so they are often used in many display or touch-related devices. 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, these metal oxide films cannot meet the flexibility requirements of display devices. Therefore, a variety of flexible transparent conductors have been developed, such as transparent conductors made of nano-scale materials.

[0003] However, the process technology of the nano-scale materials still has many problems to be solved. For example, the conventional process is to use a subtractive process, such as etching to remove unnecessary materials to achieve patterning. Such processes will cause material waste and process complexity. For another example, when using nanowires to make touch electrodes, the nanowires and the leads in the peripheral area must be overlapped. The overlapped area makes it impossible to reduce the size of the peripheral area, which in turn leads to a larger width of the peripheral area, which cannot meet the narrow frame requirements of the display. Summary of the invention

[0004] In some embodiments of the present invention, a coating structure is formed on a specific surface of a conductive nanostructure (such as a metal nanowire), and the two form a parallel characteristic to achieve the purpose of improving electrical properties to meet the application of low resistance and flexibility.

[0005] In some embodiments of the present invention, forming a coating structure on a conductive nanostructure (such as a metal nanowire) is a direct forming additive process, which is relatively simple and can reduce material costs.

[0006] In some embodiments of the present invention, peripheral leads are designed to be directly formed from modified conductive nanostructures (such as metal nanowires) to achieve a structure without overlapping, thereby forming a peripheral area with a smaller width, thereby meeting the demand for a narrow frame.

[0007] According to some embodiments of the present invention, a touch panel is characterized in that it includes: a substrate, wherein the substrate has a display area and a peripheral area; a peripheral lead, which is arranged in the peripheral area of ​​the substrate; and a touch sensing electrode, which is arranged in the display area of ​​the substrate, and the touch sensing electrode is electrically connected to the peripheral lead, wherein the peripheral lead and the touch sensing electrode include a plurality of conductive nanostructures and a film layer applied to the conductive nanostructures, and the interface between the conductive nanostructure in the peripheral lead and the film layer substantially has a coating structure.

[0008] According to some embodiments of the present invention, an electrode is characterized in that it comprises: a conductive nanostructure and a film layer applied to the conductive nanostructure, and the interface between the conductive nanostructure and the film layer substantially has a coating structure.

[0009] In some embodiments of the present invention, the coating structure includes a coating layer, and the coating layer completely covers the interface between the conductive nanostructure and the film layer. The coating structure includes a chemical plating layer, an electroplating layer, or a combination thereof.

[0010] In some embodiments of the present invention, the film layer is in an uncured state, and the coating structure is formed along the surface of the conductive nanostructure and is located at the interface between the conductive nanostructure and the film layer.

[0011] In some embodiments of the present invention, the film layer has a first layer region and a second layer region, and the curing state of the second layer region is higher than that of the first layer region; in the first layer region, the coating structure is formed along the surface of the conductive nanostructure and is located at the interface between the conductive nanostructure and the film layer. In the second layer region, at least part of the surface of the conductive nanostructure has the coating structure, or the surface of the conductive nanostructure has the coating structure and has no coating structure. Compared with the two layers, in the region with a lower degree of curing, a larger proportion of the surface of the conductive nanostructure is covered by the coating structure.

[0012] In some embodiments of the present invention, the film layer is filled between adjacent conductive nanostructures, and the coating structure does not exist independently in the film layer.

[0013] In some embodiments of the present invention, the conductive nanostructure comprises a metal nanowire, and the coating structure completely covers the interface between the metal nanowire and the film layer and forms a uniform coating layer at the interface. The uniform coating layer may be a coating layer with uniform thickness.

[0014] In some embodiments of the present invention, the coating structure is a layered structure, an island-shaped protrusion structure, a point-shaped protrusion structure, or a combination thereof made of a conductive material.

[0015] In some embodiments of the present invention, the conductive material is silver, gold, platinum, iridium, rhodium, palladium, osmium or an alloy thereof.

[0016] In some embodiments of the present invention, the coating structure is a single-layer structure made of a single metal material or alloy material; or the coating structure is a two-layer or multi-layer structure made of two or more metal materials or alloy materials.

[0017] In some embodiments of the present invention, the coating structure is a chemical copper plating layer, an electroplated copper, a chemical copper-nickel plating layer, a chemical silver plating layer or a combination thereof. The coating structure is a chemical plating layer, and the chemical plating layer completely covers the interface between the conductive nanostructure and the film layer. In other words, the surface of the conductive nanostructure and the film layer are separated by a chemical plating layer.

[0018] According to some embodiments of the present invention, it includes: adding a film layer onto a conductive layer containing a conductive nanostructure, and making the film layer reach a pre-cured or uncured state; and performing a modification step to form a coating structure on at least a portion of the surface of the conductive nanostructure, so that the interface between the conductive nanostructure and the film layer substantially has the coating structure.

[0019] In some embodiments of the present invention, the modification step includes: immersing the film layer and the conductive nanostructure in a chemical plating solution, wherein the chemical plating solution penetrates into the film layer and contacts the conductive nanostructure, so that the metal is precipitated on the surface of the conductive nanostructure. The chemical plating layer completely covers the interface between the conductive nanostructure and the film layer.

[0020] In some embodiments of the present invention, the coating structure is formed along the surface of the conductive nanostructure and is located at the interface between the conductive nanostructure and the film layer.

[0021] In some embodiments of the present invention, applying a film layer to a conductive layer containing conductive nanostructures includes: coating a polymer on the conductive layer; and controlling the curing conditions to make the polymer reach a pre-cured or incompletely cured state. The polymer is a light-curable, heat-curable, or other curable type.

[0022] In some embodiments of the present invention, adding a film layer to a conductive layer containing conductive nanostructures includes: coating a polymer on the conductive layer; controlling the curing conditions so that the polymer forms the film layer, the film layer has a first layer region and a second layer region, and the curing state of the second layer region is higher than the curing state of the first layer region.

[0023] In some embodiments of the present invention, controlling the curing conditions includes introducing oxygen and controlling the concentration of oxygen in the first layer region and the second layer region.

[0024] In some embodiments of the present invention, the modification step includes: a chemical plating step, an electroplating step or a combination thereof.

[0025] In some embodiments of the present invention, the modification step is performed only in the peripheral area.

[0026] In some embodiments of the present invention, a step of shielding the display area is further included before the modifying step.

[0027] According to some embodiments of the present invention, a method for manufacturing a touch panel is characterized in that it includes: providing a substrate having a display area and a peripheral area; arranging metal nanowires in the display area and the peripheral area to form a metal nanowire layer; applying a film layer on the metal nanowire layer, and making the film layer reach a pre-cured or uncured state; performing a patterning step, including: patterning the metal nanowire layer and the film layer located in the display area to form a touch sensing electrode and patterning the metal nanowire layer and the film layer located in the peripheral area to form a peripheral lead, the touch sensing electrode is electrically connected to the peripheral lead; performing a modification step, so that a coating structure is formed on the surface of the metal nanowire of the peripheral lead, so that the interface between the metal nanowire and the film layer substantially has the coating structure.

[0028] In some embodiments of the present invention, the modification step includes: contacting the film layer of the peripheral lead and the metal nanowire layer with a chemical plating solution, wherein the chemical plating solution penetrates into the film layer and contacts the metal nanowires, so that the metal is precipitated on the surface of the metal nanowires.

[0029] In some embodiments of the present invention, the modification step comprises a chemical plating step, an electroplating step or a combination thereof.

[0030] According to some embodiments of the present invention, a device includes a touch panel, which includes: a substrate, wherein the substrate has a display area and a peripheral area; a peripheral lead, which is arranged in the peripheral area of ​​the substrate; and a touch sensing electrode, which is arranged in the display area of ​​the substrate, and the touch sensing electrode is electrically connected to the peripheral lead, wherein the peripheral lead and the touch sensing electrode include a plurality of conductive nanostructures and a film layer applied to the conductive nanostructures, and the interface between the conductive nanostructure in the peripheral lead and the film layer substantially has a coating structure.

[0031] In some embodiments of the present invention, the device includes a display, a mobile phone, a tablet computer, a wearable device, a car device, a notebook computer, or a polarizer. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1A Schematic diagram of the first step according to some embodiments of the present invention.

[0033] Figure 1B Schematic diagram of the second step according to some embodiments of the present invention.

[0034] Figure 1C Schematic diagram of the third step according to some embodiments of the present invention.

[0035] Figure 2 FIG. 4 is a top view schematically showing a touch panel according to some embodiments of the present invention.

[0036] Figure 2A for Figure 2 Schematic cross-sectional view of line AA.

[0037] Figure 2B for Figure 2 A schematic cross-sectional view of line BB.

[0038] FIG. 3A to FIG. 3D Schematic diagram of a method for manufacturing a touch panel according to some embodiments of the present invention.

[0039] Figure 4 FIG. 4 is a schematic cross-sectional view of a touch panel according to another embodiment of the present invention.

[0040] Figure 5 FIG. 4 is a schematic diagram of a touch panel according to another embodiment of the present invention.

[0041] Figure 5A for Figure 5 Schematic cross-sectional view of line AA.

[0042] Figure 6 FIG. 4 is a schematic diagram of a touch panel according to another embodiment of the present invention.

[0043] Figure 7 FIG. 4 is a schematic diagram of a touch panel according to another embodiment of the present invention.

[0044] Figure 8 The total thickness of the first region and the second region under different curing energy conditions with 20% oxygen introduced into the film layer, and the thickness of the second region after etching with alkaline solution.

[0045] Fig. 9 SEM image showing metal nanowires electrolessly plated without a film layer.

[0046] Fig.10 This is the SEM image of the metal nanowires evolving into nanosilver wires with a coating structure over time.

[0047] Description of reference numerals:

[0048] 100: Touch panel

[0049] 110: Substrate

[0050] 120: Peripheral leads

[0051] 140: Mark

[0052] 130: Film layer

[0053] 136: Non-conductive area

[0054] 190: Metal Nanowires

[0055] 150: Protective layer

[0056] 160: Shielded wire

[0057] 180: Covering structure

[0058] VA: Display area

[0059] PA: Peripheral area

[0060] BA: Junction Area

[0061] TE1: First touch electrode

[0062] TE2: Second touch electrode

[0063] TE: Touch sensing electrode

[0064] NWL: Metal Nanowire Layer

[0065] D1: First direction

[0066] D2: Second direction DETAILED DESCRIPTION

[0067] 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.

[0068] 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%. If not explicitly stated in the text, the numerical values ​​mentioned are considered approximate values, that is, they have the error or range indicated by "about", "approximately" or "roughly".

[0069] As used herein, the term "conductive nanostructure" generally refers to a layer / film composed of nanostructures having a sheet resistance of less than 500 ohms / square, preferably less than 200 ohms / square, and more preferably less than 100 ohms / square; and a nanostructure generally refers to a structure of nanometer size, such as but not limited to a structure having at least one dimension (e.g., line diameter, length, width, thickness, etc.) of 10 -9 Meter-level linear structures, columnar structures, sheet structures, grid structures, tubular structures, etc.

[0070] Some embodiments of the present invention provide a method for modifying a conductive nanostructure (taking nanowires as an example), which may include the following steps:

[0071] like Figure 1A First, the metal nanowires 190 are arranged on the substrate 110 to form a metal nanowire layer NWL, such as a nanosilver wire layer, a nanogold wire layer or a nanocopper wire layer. The specific method of this embodiment is: a dispersion liquid or slurry (ink) containing the metal nanowires 190 is formed on the substrate 110 by a coating method, and then dried so that the metal nanowires 190 cover the surface of the substrate 110, thereby forming a metal nanowire layer NWL disposed on the substrate 110. After the above-mentioned curing / drying steps, the solvent and other substances are volatilized, and the metal nanowires 190 are randomly distributed on the surface of the substrate 110; preferably, the metal nanowires 190 are fixed on the surface of the substrate 110 without falling off to form the metal nanowire layer NWL, and the metal nanowires 190 can contact each other to provide a continuous current path, thereby forming a conductive network. In other words, the metal nanowires 190 contact each other at the intersection position to form a path for transmitting electrons. Taking silver nanowires as an example, a silver nanowire and another silver nanowire will form a direct contact pattern at the intersection, thus forming a low-resistance electron transmission path. In one embodiment, when the sheet resistance of a region or a structure is higher than 10 8 Ohm / square is considered electrical insulation, preferably higher than 10 4 In one embodiment, the sheet resistance of the silver nanowire layer composed of silver nanowires is less than 100 ohms / square.

[0072] Then as Figure 1B, a film layer 130 is provided so that the film layer 130 covers the metal nanowires 190, and the curing degree of the film layer 130 is controlled. In a specific embodiment, a suitable polymer is coated on the metal nanowires 190, and the polymer with a flowing state / property can penetrate between the metal nanowires 190 to form a filler, and the metal nanowires 190 will be embedded in the film layer 130 to form a composite structure CS; and the conditions for polymer coating and curing are controlled, such as controlling the temperature, light curing parameters, etc., so that the polymer is pre-cured or not completely cured; or the film layer 130 has different curing degrees, for example, the curing degree of the lower layer area (i.e., the area close to the substrate 110) is greater than that of the upper layer area (i.e., the area away from the substrate 110), and the upper layer area is the aforementioned pre-cured or not completely cured state. That is, in this step, the polymer is coated on the metal nanowires 190 with the film layer 130, and the metal nanowires 190 will be embedded in the pre-cured or not completely cured film layer 130 to form a composite structure CS. In some embodiments of the present invention, the film layer 130 is formed of an insulating material. For example, the material of the film layer 130 can be a non-conductive resin or other organic material, such as polyacrylate, epoxy resin, polyurethane, polysilane, polysiloxane, poly(silicon-acrylic acid), polyethylene (PE), polypropylene (PP), polyvinyl butyral (PVB), polycarbonate (PC), acrylonitrile-butadiene-styrene copolymer (ABS), poly(3,4-ethylenedioxythiophene) (PEDOT), poly(styrene sulfonic acid) (PSS) or ceramic materials, etc. In some embodiments of the present invention, the film layer 130 can be formed by spin coating, spray coating, printing, etc. In some embodiments, the thickness of the film layer 130 is about 20 nanometers to 10 micrometers, or 50 nanometers to 200 nanometers, or 30 to 100 nanometers. For example, the thickness of the film layer 130 can be about 90 nanometers or 100 nanometers. Figure 1B In the figure, the metal nanowires 190 and the film layer 130 are drawn as an integral structural layer, but the present invention is not limited thereto. The metal nanowires 190 and the film layer 130 may constitute other types of structural layers, such as a structure stacked up and down.

[0073] In one embodiment, the method for controlling the curing state of the film layer 130 is to use different energy curing conditions to cure the film layer so that the film layer reaches a non-completely cured state. Among them, the curing behavior of the film layer is to utilize the bonding changes of the film layer during curing, so the curing degree of a certain film layer can be defined as the ratio of the bonding strength of the film layer to the bonding strength of the fully cured film layer (expressed as a percentage in this embodiment). For example, for a film layer material of a commercial product, it originally requires 500mJ of light energy to be irradiated in a low-oxygen atmosphere for 4 minutes to achieve complete curing. In this embodiment, 500mJ of light energy is used for irradiation in a low-oxygen atmosphere for 2 minutes to achieve a curing state of 95% of the total curing amount. That is to say, the bonding strength measured by infrared spectroscopy under the curing conditions is 95% of the fully cured layer. Therefore, the cured film layer obtained under the conditions is defined as a curing state of 95% of the total curing amount.

[0074] In one embodiment, the film layer 130 can be controlled to have different curing states at different depths (i.e., thicknesses). Gas can be introduced during the curing of the film layer to make the gas concentrations at the surface and bottom of the film layer different, thereby promoting the curing reaction on the surface of the film layer to produce a gas barrier curing phenomenon, resulting in the film layer having a first layer region and a second layer region with different curing degrees. For example, the curing state of the second layer region belongs to the bottom of the film layer, which is a region with a higher curing degree. In contrast, the curing state of the first layer region belongs to the surface of the film layer, which is a region with a lower curing degree. The specific method is to control the gas (such as oxygen) concentration and / or curing energy under the curing conditions. The gas concentration can be 20% oxygen, 10% oxygen, 3% oxygen, or <1% oxygen, etc. The curing energy will be selected according to the material of the film layer, such as UV light energy ranging from 250mJ to 1000mJ. In the implementation method, the higher the oxygen concentration, the more obvious the phenomenon of oxygen blocking curing on the surface of the film layer will be, and the thickness of the first region with a lower curing degree will be thicker, while the thickness of the second region with a higher curing degree will be thinner. Therefore, if the thickness of the first region is 20% oxygen, 10% oxygen, 3% oxygen or <1% oxygen in order from thick to thin. In a specific embodiment, under the conditions of 20% oxygen and 500mJ of curing energy, the curing degree of the first region is about 60%, and the thickness of the first region is about 23.4nm (or 12% of the total film thickness); while the curing degree of the second region is about 99-100% (close to complete curing), and the thickness of the second region is about 168.1nm (or 88% of the total film thickness). Figure 8The total thickness of the first region (uncured) and the second region (nearly completely cured or completely cured) formed by irradiation with curing energy of 250mJ, 500mJ and 1000mJ respectively under the condition of 20% oxygen in the film layer, and the thickness of the second region remaining after the above film layer is etched with alkali solution. It can be observed that as the curing energy increases, the thickness of the first region will decrease (i.e. the thickness reduced after etching). When the curing energy is 1000mJ, the thickness of the first region is about 8.8nm (or 5% of the total film thickness); and the thickness of the second region is about 195.9nm (or 95% of the total film thickness).

[0075] It is worth noting that the present invention focuses on discussing the film layer 130 applied to the metal nanowire 190, and controls the curing degree or curing depth of the film layer 130 so that the coating structure 180 can grow along the surface of the metal nanowire 190 to form a modified structure at the interface between the metal nanowire 190 and the film layer 130. In the coating step of the metal nanowire 190 dispersion or slurry (ink), the dispersion or slurry may also contain polymers and other similar components, but it is not the focus of the present invention. The curing degree of the film layer 130 can be controlled at 0%, 30%, 60%, 75%, 95%, 98%, 0% to 95%, 0% to 98%, 95% to 98%, 60% to 98%, 60% to 75%, etc. As mentioned above, the incomplete curing or only pre-curing referred to in the embodiments of the present invention can be defined as the bonding strength of the film layer is different from the bonding strength of the fully cured film layer, that is, the ratio of the two is not 100% and it can fall within the scope of the embodiments of the present invention.

[0076] Then as Figure 1C , and then a modification step is performed to form a metal nanowire layer NWL composed of a plurality of modified metal nanowires 190. That is, after the modification, at least a portion of the initial metal nanowires 190 is modified to form a coating structure 180 on its surface to form the modified metal nanowires 190. Figure 1B , 1CIn the figure, the symbols "v" and "o" represent the metal nanowires 190 before and after modification. In a specific embodiment, the coating structure 180 can be formed by chemical plating / electrolysis, and the coating structure 180 can be a layered structure, an island protrusion structure, a dot protrusion structure or a combination thereof made of a conductive material, and the coverage rate accounts for more than 80%, 90-95%, 90-99%, or 90-100% of the total surface area (a coverage rate of 100% means that no surface of the initial metal nanowire 190 is exposed); the aforementioned conductive material can be silver, gold, platinum, nickel, copper, iridium, rhodium, palladium, osmium or alloys containing the aforementioned materials, or alloys not containing the aforementioned materials, etc. In a specific embodiment, the coating structure 180 is a single-layer structure made of a single conductive material, such as forming a chemically plated copper layer, an electroplated copper layer, or a chemically plated copper-nickel alloy layer; or the coating structure 180 is a two-layer or multi-layer structure made of two or more conductive materials, such as first forming a chemically plated copper layer and then forming a chemically plated silver layer.

[0077] In a specific embodiment, the following chemical copper plating solution (containing copper ion solution, chelating agent, alkali agent, reducing agent, buffer and stabilizer, etc.) can be prepared; the metal nanowires 190 and the film layer 130 are immersed in the chemical copper plating solution, and the chemical copper plating solution can penetrate into the pre-cured or incompletely cured film layer 130 and contact the surface of the metal nanowires 190 by using capillary phenomena and other effects, and the metal nanowires 190 are used as catalyst points or nucleation points to facilitate the precipitation of copper, and then the chemical copper plating layer is deposited on the metal nanowires 190 to form a coating structure 180. The coating structure 180 will generally grow in accordance with the initial form of the metal nanowire 190, and will form a structure covering the metal nanowire 190 as the modification time progresses; in contrast, there will be no copper precipitation at the position where there is no metal nanowire 190 in the original composite structure CS. In other words, after good control, the coating structure 180 is formed on the interface between the metal nanowire 190 and the film layer 130, and there is no coating structure 180 that does not contact the surface of the metal nanowire 190 and exists alone in the film layer 130. Therefore, after the modification step, the metal nanowire 190 in the conductive network will be coated by the coating structure 180, and the coating structure 180 will be located between the interface formed by the metal nanowire 190 and the film layer 130; the coating structure 180 and the metal nanowire 190 it covers can be regarded as a whole, and the gap between the nanowires is still occupied by the material of the film layer 130.

[0078] In a specific embodiment, the film layer 130 and the chemical plating solution / electrolytic solution can be made of materials that match each other. For example, a polymer that is not alkali-resistant can be selected to make the film layer 130, and the chemical plating solution can be an alkaline solution. Therefore, in this step, in addition to utilizing the incompletely solidified state of the aforementioned film layer, the chemical plating solution can also be used to attack (similar to etching) the incompletely solidified film layer 130 to facilitate the above-mentioned modification reaction.

[0079] The principle is described below, but is not limited thereto. In the early stage when the metal nanowires 190 and the film layer 130 are immersed in the chemical plating solution / electrolytic solution, the solution will first attack the film layer 130 that is not completely solidified. When the solution contacts the metal nanowires 190, the metal ions (such as copper ions) begin to develop with the metal nanowires 190 (such as nanosilver wires) as seeds, and the above-mentioned coating structure 180 grows on the surface of the metal nanowires 190 as the immersion time increases. On the other hand, the film layer 130 acts as a control layer or a limiting layer in the above-mentioned reaction process, which limits the growth reaction of the coating structure 180 to the interface between the metal nanowires 190 and the film layer 130, so that the coating structure 180 can be controlled and uniformly grown. Fig. 9 It is shown that the metal nanowires 190 are subjected to the above-mentioned chemical plating without the protection of the film layer 130, and it can be found that the copper layer grows randomly and uncontrollably. Thick copper layers grow on some metal nanowires 190, but no copper layers appear on some metal nanowires 190; that is, the film layer 130 can achieve the effect of limiting the location of copper precipitation to the interface between the metal nanowires 190 and the film layer 130, so the present invention has better consistency when used in sensing / transmitting signals.

[0080] Finally, a curing step may be included to completely cure the film layer 130. The complete curing of the film layer 130 may be performed by light, heat or other means.

[0081] The following table shows a specific embodiment of the present invention. It can be found that the curing degree of the film layer 130 is 0%, 95%, 98%, 0% to 95%, 0% to 98%, 95% to 98% and other conditions for copper plating, which can effectively reduce the surface resistance (or sheet resistance) of the film layer. The curing degree can be measured in a variety of ways. In addition to the calculation of the above-mentioned bond strength, for example, the polymer film is subjected to solvent extraction, the weight of the uncured polymer dissolved in the solvent is measured, and the weight is compared with the total weight of the cured and uncured polymers to calculate the solubility percentage (%Sol); for example, for thermosetting polymer materials, thermal analysis technology can also be used to determine the curing degree.

[0082]

[0083] In the above method, the coating structure 180 is formed on the surface of each metal nanowire 190 and covers the entire surface of the metal nanowire 190, and grows outward. In one embodiment, a highly conductive material can be selected to make the coating structure 180, for example, copper is used as the coating structure 180 to cover the surface of the nanosilver wire and is located at the interface between the nanosilver wire and the film layer. It is worth noting that although the conductivity of the silver material is higher than that of the copper material, due to the size of the nanosilver wire and the contact state, the overall conductivity of the silver nanowire layer is lower (but the resistance is still low and sufficient to transmit electrical signals), and after modification, the conductivity of the nanosilver wire 190 with the coating structure 180 is higher than that of the unmodified nanosilver wire 190, that is, the modified metal nanowire layer NWL can form a low-resistance conductive layer (compared with the unmodified metal nanowire layer NWL, the surface resistance can be reduced by about 100 to 10,000 times); and the conductive layer can be used to make electrode structures for various purposes, such as conductive substrates or wireless charging coils, antenna structures, etc. used in the flexible field. Specifically, the electrode structure may include at least metal nanowires and an additional film layer coated on the metal nanowires. The surface of at least a portion or all of the metal nanowires (i.e., the interface corresponding to the metal nanowire 190 and the film layer 130) has a coating layer. The introduction of the coating layer can improve the conductivity of the metal nanowire layer NWL. Fig.10 The SEM evolution diagram of the metal nanowire 190 evolving into the silver nanowire with the coating structure 180 as the electroless plating time passes. Since the copper layer is along the surface of the metal nanowire (i.e., the interface corresponding to the metal nanowire 190 and the film layer 130), after plating, the observed copper morphology will be quite similar to the initial morphology of the metal nanowire (e.g., both are linear structures), and the copper will grow uniformly to form an outer layer structure with similar size (e.g., thickness).

[0084] The present invention can be applied to manufacturing a touch panel (such as Figure 2 ), for example but not limited to a touch panel used in conjunction with a display, the touch panel 100 in some embodiments includes a substrate 110, a peripheral lead 120, and a touch sensing electrode TE, wherein the touch sensing electrode TE includes a plurality of unmodified initial conductive nanostructures, the peripheral lead 120 includes a plurality of modified conductive nanostructures, and the modified conductive nanostructures have a coating structure 180 (see Figure 1C ), the conductive nanostructure may be a metal nanowire 190. Figure 2 FIG. 1 is a top view of a touch panel 100 according to some embodiments of the present invention. Figure 2The touch panel 100 may include a substrate 110, peripheral leads 120, a mark 140 and a touch sensing electrode TE, and the touch sensing electrode TE is roughly located in the display area VA, which is patterned by a metal nanowire layer NWL composed of a plurality of unmodified initial metal nanowires 190; the modified metal nanowires 190 have a coating structure 180, and the modified metal nanowires 190 are patterned to form the peripheral leads 120 and / or the mark 140. By forming the coating structure 180 at the interface between the metal nanowires 190 and the film layer 130, the conductivity can be improved to produce the peripheral leads 120. In addition, in the display area VA, the metal nanowires 190 are in direct contact with the external film layer 130 (that is, the metal nanowires 190 in the display area VA are not modified). In other words, the coating structure 180 will not be formed on the surface of the metal nanowires 190 in the display area VA, so the good optical properties of the conductive network formed by the metal nanowires 190 in the display area VA can be maintained.

[0085] The number of the peripheral lead 120, the mark 140 and the touch sensing electrode TE can be one or more, and the numbers shown in the following specific embodiments and drawings are only for illustration purposes and do not limit the present invention. Figure 2 , the substrate 110 has 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 can 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 can be an L-shaped area disposed on the left side and bottom side of the display area VA. Figure 2 As shown, this embodiment has eight sets of peripheral leads 120, all disposed in the peripheral area PA of the substrate 110; the touch sensing electrodes TE are disposed in the display area VA of the substrate 110 and electrically connected to the peripheral leads 120. This embodiment further has two sets of marks 140, both disposed in the peripheral area PA of the substrate 110.

[0086] See also FIG. 3A to FIG. 3D , which shows the manufacturing method of the touch panel 100: first, a substrate 110 is provided, on which a peripheral area PA and a display area VA are pre-defined. Then, an unmodified metal nanowire 190 is disposed on the substrate 110 to form a metal nanowire layer NWL in the peripheral area PA and the display area VA (such as Figure 3A ); then, a film layer 130 is disposed on the unmodified metal nanowires 190, so that the film layer 130 covers the unmodified metal nanowires 190, and the film layer 130 is in a pre-cured or uncured state (such as Figure 3B ); then patterning is performed to form a metal nanowire layer NWL having a pattern (such as Figure 3C), wherein the metal nanowire layer NWL located in the display area VA is patterned to form a touch sensing electrode TE (which can cooperate with Figure 2 ), and the metal nanowire layer NWL of the peripheral area PA is patterned to form a peripheral lead 120 (please cooperate with Figure 2 ); then a modification step is performed to form a coating structure 180 (such as Figure 3D ), wherein the metal nanowire layer NWL located in the display area VA is not modified, and the metal nanowire layer NWL located in the peripheral area PA is modified. That is to say, due to the aforementioned modification step, the peripheral lead 120 is composed of the modified metal nanowires 190.

[0087] The above steps are described in more detail below.

[0088] See also Figure 3A First, a metal nanowire layer NWL including at least metal nanowires 190, such as a nanosilver wire layer, a nanogold wire layer or a nanocopper wire layer, is coated on the peripheral area PA and the display area VA on the substrate 110; the first part of the metal nanowire layer NWL is mainly located in the display area VA, and the second part is mainly formed in the peripheral area PA. The specific method of this embodiment is: a dispersion liquid or slurry (ink) containing metal nanowires 190 is formed on the substrate 110 by a coating method, and dried so that the metal nanowires 190 cover the surface of the substrate 110, and then formed into a metal nanowire layer NWL disposed on the substrate 110. After the above-mentioned curing / drying step, the solvent and other substances are volatilized, and the metal nanowires 190 are randomly distributed on the surface of the substrate 110; preferably, the metal nanowires 190 are fixed on the surface of the substrate 110 without falling off to form a metal nanowire layer NWL, and the metal nanowires 190 can contact each other to provide a continuous current path, thereby forming a conductive network. In other words, the metal nanowires 190 contact each other at the intersection to form a path for transmitting electrons. Taking silver nanowires as an example, a silver nanowire and another silver nanowire will form a direct contact state at the intersection (i.e., a silver-silver contact interface), so a low-resistance electron transmission path is formed, and the subsequent modification operation will not affect or change the low-resistance structure of the "silver-silver contact", and the high-conductivity coating structure 180 is coated on the surface of the metal nanowire 190, so the electrical characteristics of the terminal product will be improved.

[0089] In an embodiment of the present invention, the dispersion liquid may be 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), sulfonate, sulfate, disulfonate, sulfosuccinate, phosphate or fluorine-containing surfactant, etc. The dispersion liquid or slurry containing the metal nanowires 190 may be formed on the surface of the substrate 110 and the aforementioned metal layer ML by any method, such as but not limited to: screen printing, nozzle coating, roller coating and other processes; in one embodiment, the dispersion liquid or slurry containing the metal nanowires 190 may be coated on the surface of the continuously supplied substrate 110 and the aforementioned metal layer ML by a roll to roll (RTR) process.

[0090] As used herein, "metal nanowires" is a collective term, 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 does not affect the scope of protection claimed by the present invention; and at least one cross-sectional dimension (i.e., cross-sectional diameter) of a single metal nanowire is less than about 500nm, preferably less than about 100nm, and more preferably less than about 50nm; and the metal nanostructures referred to as "wires" in the present invention mainly have a high aspect ratio, for example, between about 10 and 100,000, and more specifically, the aspect ratio (length: cross-sectional diameter) of the metal nanowires can be greater than about 10, preferably greater than about 50, and more preferably greater than about 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.

[0091] See also Figure 3B, and perform the step of coating the film layer 130. In one embodiment, the film layer 130 is disposed on the unmodified metal nanowires 190 so that the film layer 130 covers the unmodified metal nanowires 190, and then the patterning step and the modification step are performed in sequence. In a specific embodiment, the polymer of the film layer 130 after coating can penetrate between the metal nanowires 190 to form a filler, and the metal nanowires 190 will be embedded in the film layer 130 to form a composite structure CS. In other words, the unmodified metal nanowires 190 will be embedded in the film layer 130 to form a composite structure CS. In some embodiments of the present invention, the film layer 130 is formed of an insulating material. For example, the material of the film layer 130 can be a non-conductive resin or other organic material. In some embodiments of the present invention, the film layer 130 can be formed by spin coating, spray coating, printing, etc. In some embodiments, the thickness of the film layer 130 is about 20 nanometers to 10 micrometers, or 50 nanometers to 200 nanometers, or 30 to 100 nanometers. For example, the thickness of the film layer 130 can be about 90 nanometers or 100 nanometers. In order to effectively perform the modification step, the polymer (i.e., the film layer 130) will form an uncured or pre-cured state, and the details can be referred to the above description.

[0092] Then patterning is performed, such as Figure 3C After the patterning step, the metal nanowire layer NWL and the film layer 130 formed by the unmodified metal nanowires 190 in the display area VA are patterned to form an electrode structure; similarly, the metal nanowire layer NWL and the film layer 130 formed by the unmodified metal nanowires 190 in the peripheral area PA are also patterned to form an electrode structure, and the electrode structures in these two areas constitute an electrode group that can be applied to touch sensing.

[0093] In one embodiment, the metal nanowire layer NWL containing the unmodified metal nanowires 190 in the display area VA and the peripheral area PA can be etched simultaneously, and an etching mask (such as a photoresist) can be used to form a patterned metal nanowire layer NWL in the display area VA and the peripheral area PA at one time in the same process. According to a specific embodiment, when the metal nanowire layer NWL is composed of silver nanowires, the etching solution can be used for components that can etch silver, for example, the main component of the etching solution is H 3 PO 4 (ratio of about 55% to 70%) and HNO 3 (ratio of about 5% to 15%), so as to remove the silver material in the same process. In another specific embodiment, the main components of the etching solution are ferric chloride / nitric acid or phosphoric acid / hydrogen peroxide.

[0094] like Figure 3CAs shown in FIG. 1 , the metal nanowire layer NWL with a pattern formed on the peripheral area PA is the peripheral lead 120. In another embodiment, the peripheral lead 120 and the mark 140 (which can be used in conjunction with the reference 140) formed by the second portion of the metal nanowire layer NWL can be formed on the peripheral area PA. Figure 2 In this embodiment, the mark 140 can be widely interpreted as a pattern with non-electrical functions, but is not limited thereto. In some embodiments of the present invention, the peripheral lead 120 and the mark 140 can be made of the same metal nanowire layer NWL.

[0095] Similarly, in the patterning step, the metal nanowire layer NWL in the display area VA is patterned. In other words, the first portion of the metal nanowire layer NWL in the display area VA can be patterned using the aforementioned etching solution in conjunction with an etching mask (such as a photoresist) to form the touch sensing electrode TE of this embodiment in the display area VA (such as Figure 3C As shown in the figure, the touch sensing electrode TE can be electrically connected to the peripheral lead 120. Specifically, the touch sensing electrode TE can be a metal nanowire layer NWL that at least includes unmodified metal nanowires 190. In general, the metal nanowire layer NWL after patterning forms the touch sensing electrode TE in the display area VA, and forms the peripheral lead 120 in the peripheral area PA, so the electrodes in the two areas are made of the same layer of material to achieve electrical connection for signal transmission between the display area VA and the peripheral area PA. In another embodiment, the metal nanowire layer NWL and the film layer 130 can also form a mark 140 in the peripheral area PA, and the mark 140 can be widely interpreted as a non-electrical functional pattern, but is not limited thereto. In some embodiments of the present invention, the peripheral lead 120 and the mark 140 can be made of the same layer of metal nanowire layer NWL.

[0096] See also Figure 3D , and then a modification step is performed to form a metal nanowire layer NWL composed of a plurality of modified metal nanowires 190. That is, after the modification, at least a portion of the initial metal nanowires 190 in the metal nanowire layer NWL is modified to form a coating structure 180 on its surface to form the modified metal nanowires 190. In a specific embodiment, the coating structure 180 can be formed by a chemical plating method, and a chemical plating solution is infiltrated into the film layer 130 that is not completely solidified, so that the reactive metal ions in the chemical plating solution are precipitated on the surface of the metal nanowire 190 to form the coating structure 180, which can be a layered structure made of a conductive material, an island-shaped protrusion structure, a dot-shaped protrusion structure, or a combination thereof; the coating structure 180 can also be a single-layer or multi-layer structure made of a single material or an alloy material, or a single-layer or multi-layer structure made of multiple materials or alloy materials.

[0097] It is worth noting that the modification step is performed along the surface of the metal nanowire 190, so the shape of the coating structure 180 will grow roughly in accordance with the shape of the metal nanowire 190. In the modification step, the growth conditions of the coating structure 180 (such as chemical plating time, chemical plating solution composition concentration, etc.) can be controlled so that the coating structure 180 will not grow excessively, but only coat the surface of the metal nanowire 190; in addition, as mentioned above, the film layer 130 that is not fully solidified also plays a role in limiting and controlling. Accordingly, the coating structure 180 formed by the modification step will not be precipitated / grown alone on the film layer 130 without contacting the metal nanowire 190, and the coating structure 180 will be formed between the surface of the metal nanowire 190 and the film layer 130; in one embodiment, the film layer 130 mentioned above is still filled between adjacent metal nanowires 190. On the other hand, the coating structure 180 formed by chemical plating / electrolytic plating has a high density. Compared with the size of the peripheral lead 120 (for example, 10um line width), the defect size of the coating structure 180 is 0.01 to 0.001 times the size of the peripheral lead 120. Therefore, even if defects occur in the coating structure 180, it will not cause problems such as broken wires of the peripheral lead 120.

[0098] See also Figure 3D In some embodiments of the present invention, the modification step is performed only in the peripheral area PA. Figure 3D A “v” symbol is drawn in the touch sensing electrode TE to represent that the touch sensing electrode TE includes the original metal nanowires 190 that have not been modified; and Figure 3D The peripheral lead 120 is shown with an “o” symbol to represent that the peripheral lead 120 is composed of the modified metal nanowire 190. For the sake of simplicity, Figure 3D The coating structure 180 is not drawn in the figure. In detail, after the above-mentioned patterning step, a photoresist or similar material can be covered on the display area VA to shield the touch sensing electrode TE, so that the chemical plating solution can penetrate into the film layer 130 that is not completely solidified in the peripheral area PA, and the reactive metal ions are precipitated on the surface of the metal nanowires 190 in the peripheral area PA through an oxidation-reduction reaction to form a coating structure 180 to form the modified metal nanowires 190. Since the touch sensing electrode TE is still composed of the metal nanowires 190 before modification, it has good light transmittance, for example, the light transmittance (Transmission) of visible light (such as a wavelength between 400nm-700nm) is greater than about 90%, 91%, 92%, 93% or more.

[0099] A curing step may further be included to cure the pre-cured or incompletely cured film layer 130 to a completely cured state.

[0100] By following the above steps, you can make Figure 2In the touch panel 100 shown, for example, the patterned metal nanowire layer NWL in the display area VA constitutes the touch sensing electrode TE of the touch panel 100; and the patterned metal nanowire layer NWL in the peripheral area PA constitutes the peripheral lead 120 of the touch panel 100, and the metal nanowire 190 in the peripheral lead 120 has a coating structure 180 (the "o" symbol in the figure represents the modified metal nanowire 190), and the peripheral lead 120 can be connected to an external controller for touch or other signal transmission. As described above, the coating structure 180 can have the same or similar structural appearance as the metal nanowire 190, and the film layer 130 will be filled between adjacent metal nanowires 190.

[0101] In a variant embodiment, the touch panel 100 of the present invention may be manufactured using a different process sequence. For example, a substrate 110 is first provided, on which a peripheral area PA and a display area VA are pre-defined. Then, unmodified metal nanowires 190 are disposed on the substrate 110 to form a metal nanowire layer NWL in the peripheral area PA and the display area VA. Then, a film layer 130 is disposed on the unmodified metal nanowires 190, so that the film layer 130 covers the unmodified metal nanowires 190, and the film layer 130 is in a pre-cured or uncured state. Then, a modification step is performed to form a coating structure 180 on the aforementioned metal nanowires 190, wherein the metal nanowires in the display area VA are The metal nanowires 190 are not modified, but the metal nanowires 190 in the peripheral area PA are modified. Then, patterning is performed to form a metal nanowire layer NWL with a pattern, wherein the metal nanowire layer NWL before modification in the display area VA is patterned to form the touch sensing electrode TE, and the metal nanowire layer NWL after modification in the peripheral area PA is patterned to form the peripheral lead 120. That is to say, due to the aforementioned modification step, the peripheral lead 120 is composed of the modified metal nanowires 190.

[0102] The following only describes the adjusted steps, and the remaining omitted parts can refer to the description of the previous embodiment.

[0103] The modification step of this embodiment can use photoresist or similar materials to cover the display area VA to block the first part of the metal nanowire layer NWL in the display area VA, and only modify the second part of the metal nanowire layer NWL in the peripheral area PA, so that the reactive metal ions in the chemical plating solution are precipitated on the surface of the metal nanowire 190 in the peripheral area PA to form a coating structure 180, so as to form the modified metal nanowire 190.

[0104] The patterning step of this embodiment can use an etching solution that can simultaneously etch the metal nanowires 190 before modification and the metal nanowires 190 after modification, and cooperate with an etching mask (such as a photoresist) to form a metal nanowire layer NWL with a pattern in the display area VA and the peripheral area PA at one time in the same process. In one embodiment, the metal nanowires 190 before modification and the metal nanowires 190 after modification can be etched simultaneously, which means that the etching rate ratio of the etching medium to the metal nanowires 190 before modification and the metal nanowires 190 after modification is between about 0.1-10 or 0.01-100.

[0105] According to a specific embodiment, when the metal nanowire layer NWL is composed of silver nanowires and has a copper coating structure 180 on its surface, the etching solution can be used for etching components that can etch copper and silver. For example, the main component of the etching solution is H 3 PO 4 (ratio of about 55% to 70%) and HNO 3 (ratio of about 5% to 15%), so as to remove copper material and silver material in the same process. In another specific embodiment, the main components of the etching solution are ferric chloride / nitric acid or phosphoric acid / hydrogen peroxide.

[0106] In the patterning step, the first part of the metal nanowire layer NWL in the display area VA can be patterned with the aforementioned etching solution in conjunction with an etching mask (such as a photoresist) to produce the touch sensing electrode TE of this embodiment in the display area VA, and the touch sensing electrode TE can be electrically connected to the peripheral lead 120. Specifically, the touch sensing electrode TE can be a metal nanowire layer NWL that at least includes the pre-modified metal nanowire 190. In the peripheral area PA, the modified metal nanowire 190 forms the peripheral lead 120, thereby achieving an electrical connection between the touch sensing electrode TE and the peripheral lead 120 for signal transmission. In this embodiment, the metal nanowire layer NWL can also form a mark 140 in the peripheral area PA, and the mark 140 can be widely interpreted as a non-electrical functional pattern, but is not limited thereto. In some embodiments of the present invention, the peripheral lead 120 and the mark 140 can be made of the modified metal nanowire 190 in the same layer.

[0107] In a variant embodiment, the metal nanowire layer NWL located in the display area VA and the peripheral area PA can be patterned by different etching steps (i.e., using different etching solutions). For example, when the metal nanowire layer NWL is a nanosilver layer and the coating structure 180 is a copper layer, the etching solution used in the display area VA can be an etching solution that only has the ability to etch silver, and the etching solution used in the peripheral area PA can be an etching solution that has the ability to etch silver / copper.

[0108] The touch panel 100 of the present invention can also be manufactured through the above steps. The specific structure is as described above and will not be repeated here.

[0109] Please come back Figure 2 , Figure 2A , Figure 2B For the convenience of explanation, the cross-section of the peripheral lead 120 and the mark 140 in this article is a quadrilateral (for example Figure 2A The drawn rectangle), but the structural type or quantity of the peripheral leads 120 and the marks can be changed according to actual applications and are not limited by the text and drawings in this article.

[0110] In this embodiment, the mark 140 is disposed in the bonding area BA of the peripheral area PA (see Figure 2 and Figure 2A ), which may be a docking alignment mark, that is, a mark used to align a flexible circuit board (not shown) with the touch panel 100 in the step of connecting an external circuit board, such as a flexible circuit board, to the touch panel 100 (i.e., the bonding step). However, the present invention does not limit the placement or function of the mark 140. For example, the mark 140 may be any inspection mark, pattern or number required in the process, which are all within the scope of protection of the present invention. The mark 140 may have any possible shape, such as a circle, a quadrilateral, a cross, an L-shape, a T-shape, etc.

[0111] like Figure 2A As shown, in the peripheral area PA, there is a non-conductive region 136 between adjacent peripheral leads 120 to electrically block the adjacent peripheral leads 120 and thus avoid short circuits. In this embodiment, the non-conductive region 136 is a gap to isolate the adjacent peripheral leads 120.

[0112] like Figure 2B As shown, in the display area VA, there is a non-conductive region 136 between adjacent touch sensing electrodes TE to electrically block adjacent touch sensing electrodes TE and thus avoid short circuit. That is to say, there is a non-conductive region 136 between the sides of adjacent touch sensing electrodes TE, and in this embodiment, the non-conductive region 136 is a gap to isolate adjacent touch sensing electrodes TE; in one embodiment, the above-mentioned etching method can be used to form the gap between adjacent touch sensing electrodes TE. In this embodiment, the touch sensing electrode TE and the first intermediate layer M1 can be made of the same metal nanowire layer NWL (such as a nano silver wire layer), so the metal nanowire layer will form the touch sensing electrode TE in the display area VA, and form the peripheral lead 120 in the peripheral area PA, and the touch sensing electrode TE and the peripheral lead 120 form a connection structure at the junction of the display area VA and the peripheral area PA, so that the touch sensing electrode TE and the peripheral lead 120 form a conductive circuit.

[0113] In some embodiments of the present invention, the peripheral leads 120 of the touch panel 100 can be directly formed by yellow light and etching processes, which are high-precision processes and do not require alignment, so there is no need to reserve alignment error space in the peripheral area, thereby reducing the width of the peripheral area PA, thereby meeting the narrow frame requirements of the display. Specifically, the width of the peripheral leads 120 of the touch panel 100 of some embodiments of the present invention is about 5um to 30um, and the distance between adjacent peripheral leads 120 is about 5um to 30um, or the width of the peripheral leads 120 of the touch panel 100 is about 3um to 20um, and the distance between adjacent peripheral leads 120 is about 3um to 20um, and the width of the peripheral area PA can also reach a size of less than about 2mm, which reduces the frame size by about 20% or more compared with traditional touch panel products.

[0114] like Figure 2 , the touch sensing electrodes TE are arranged in a non-staggered manner. For example, the touch sensing electrodes TE are long strip electrodes extending along the first direction D1 and having a width varying in the second direction D2, and are not staggered with each other. However, in other embodiments, the touch sensing electrodes TE may have an appropriate shape, and the scope of the present invention should not be limited thereto. In this embodiment, the touch sensing electrodes TE are arranged in a single layer, wherein the touch position can be obtained by detecting the change in the capacitance value of each touch sensing electrode TE.

[0115] In the present embodiment, the composite structure CS of the display area VA (i.e., the combined structure of the unmodified metal nanowires 190 and the film layer 130) may have conductivity and light transmittance. For example, the light transmittance (transmission) of the touch sensing electrode TE for visible light (e.g., wavelength between about 400nm-700nm) may be greater than about 80%, and the surface resistivity (surface resistance) is between about 10 and 1000 ohms / square; or, the light transmittance (transmission) of the touch sensing electrode TE for visible light (e.g., wavelength between about 400nm-700nm) is greater than about 85%, and the surface resistivity (surface resistance) is between about 50 and 500 ohms / square. In one embodiment, the light transmittance (transmission) of the touch sensing electrode TE for visible light (e.g., wavelength between about 400nm-700nm) is greater than about 88% or greater than about 90%. In one embodiment, the haze of the touch sensing electrode TE is less than 3.0, 2.5, 2.0, or 1.5.

[0116] In some embodiments, the formed metal nanowires 190 may be further post-processed to improve the contact characteristics of the metal nanowires 190 at the intersections, such as increasing the contact area, thereby improving the conductivity. The post-processing may include a process step such as heating, plasma, corona discharge, UV ozone, pressure, or a combination of the above processes. For example, after the step of curing to form the metal nanowire layer, pressure may be applied thereto using a roller. In one embodiment, a pressure of 50 to 3400 psi may be applied to the metal nanowire layer by one or more rollers, preferably 100 to 1000 psi, 200 to 800 psi, or 300 to 500 psi; and the step of applying pressure is preferably implemented before the step of coating the film layer 130. In some embodiments, heating and pressure post-treatment can be performed simultaneously; in detail, the formed metal nanowire 190 can be subjected to pressure through one or more rollers as described above, and heated at the same time, 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 metal nanowire 190. In some embodiments, the metal nanowire 190 can be preferably exposed to a reducing agent for post-treatment, for example, the metal nanowire 190 composed of nanosilver wires can be 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 (H 2 ); and the exposure time is about 10 seconds to about 30 minutes, preferably about 1 minute to about 10 minutes. After the above post-treatment steps, the contact strength or area of ​​the metal nanowires 190 at the intersections can be enhanced, and the contact surface of the metal nanowires 190 at the intersections (i.e., the first surface 191) can be ensured not to be affected by the modification treatment.

[0117] In one embodiment, the touch panel 100 may further include a protective layer 150, which may be applied to various embodiments. Figure 2B The embodiments are described as examples. Figure 4 The display protection layer 150 is formed on Figure 2B 1 is a cross-sectional schematic diagram of an embodiment of the present invention. It is worth noting that the material of the protective layer 150 can refer to the example material of the film layer 130 described above. In one embodiment, the protective layer 150 covers the touch panel 100 in an all-round manner, that is, the protective layer 150 covers the touch sensing electrodes TE, the peripheral leads 120 and the mark 140. The protective layer 150 can be filled in the non-conductive area 136 between adjacent peripheral leads 120 to isolate the adjacent peripheral leads 120, or the protective layer 150 can be filled in the non-conductive area 136 between adjacent touch sensing electrodes TE to isolate the adjacent touch sensing electrodes TE.

[0118] Figure 5 is a top view schematic diagram of a touch panel 100 according to some embodiments of the present invention. The touch sensing electrode TE of this embodiment adopts a double-layer configuration; Figure 5A for Figure 5 Cross-sectional view along line AA.

[0119] For the sake of convenience, the configuration adopted in this embodiment is described with the first touch electrode TE1 and the second touch electrode TE2. The first touch electrode TE1 is formed on one side (such as the upper surface) of the substrate 110, and the second touch electrode TE2 is formed on the other side (such as the lower surface) of the substrate 110, so that the first touch electrode TE1 and the second touch electrode TE2 are electrically insulated from each other; and the first touch electrode TE1 is electrically connected to the corresponding peripheral lead 120; similarly, the second touch electrode TE2 is connected to the corresponding peripheral lead 120. The first touch electrode TE1 is a plurality of long strip electrodes arranged along the first direction D1, and the second touch electrode TE2 is a plurality of long strip electrodes arranged along the second direction D2. As shown in the figure, the long strip touch sensing electrodes TE1 and the long strip touch sensing electrodes TE2 extend in different directions and are interlaced with each other. The first touch sensing electrode TE1 and the second touch sensing electrode TE2 can be used to transmit control signals and receive touch sensing signals, respectively. From this, the touch position can be obtained by detecting the signal change (e.g., capacitance change) between the first touch sensing electrode TE1 and the second touch sensing electrode TE2. With this arrangement, the user can perform touch sensing at each point on the substrate 110. As in the above embodiment, the first touch sensing electrode TE1 and / or the second touch sensing electrode TE2 can be made of at least the unmodified metal nanowire 190 and the film layer 130, and the peripheral leads 120 and / or the marks 140 ( Figure 5 and Figure 5A The mark 140 is not drawn, but it does not affect the description of this embodiment) can be made of the modified metal nanowire 190 and the film layer 130, that is, the peripheral leads 120 and / or the mark 140 located on both sides of the substrate 110 can form the coating structure 180 on the surface of the metal nanowire 190 according to the aforementioned method.

[0120] The double-sided touch panel manufactured in the embodiment of the present invention can be manufactured in the following manner: first, a substrate 110 is provided, on which a pre-defined peripheral area PA and a display area VA are provided. Then, a metal nanowire layer NWL is formed on the first and second surfaces (such as the upper surface and the lower surface) of the substrate 110 in the peripheral area PA and the display area VA of the first and second surfaces respectively; then, an uncured film layer 130 is formed on the metal nanowire layer NWL; then, a double-sided patterning step is performed, such as double-sided yellowing, etching, etc., to form a metal nanowire layer NWL with a pattern on the first and second surfaces of the substrate 110; then, a double-sided modification step is performed, so that the metal nanowires 190 on the upper and lower surfaces of the substrate 110 are formed with a coating structure 180, for example, a modification step is performed on the peripheral area PA of the upper and lower surfaces of the substrate 110, and the modified metal nanowires 190 constitute the peripheral leads 120.

[0121] In one embodiment, the patterned product may be immersed in a plating solution, and the upper and lower surfaces of the substrate 110 may be modified at the same time.

[0122] Similar to the aforementioned embodiment, any surface (such as the upper surface or the lower surface) of the substrate 110 may further include a mark 140 , which is also formed by the modified metal nanowires 190 .

[0123] It is worth noting that the specific method for the double-sided touch panel can refer to the previous description of the single-sided touch panel, and the implementation method described in the previous paragraph is only for illustration and is not intended to limit the present invention.

[0124] The manufacturing method of the double-sided touch panel in the embodiment of the present invention can be formed by stacking two sets of single-sided touch panels in the same direction or in opposite directions. Taking stacking in the opposite direction as an example, the touch electrodes of the first set of single-sided touch panels can be arranged upward (for example, closest to the user, but not limited to this), and the touch electrodes of the second set of single-sided touch panels can be arranged downward (for example, farthest from the user, but not limited to this), and the substrates of the two sets of touch panels can be assembled and fixed with optical glue or other similar adhesives to form a double-sided touch panel.

[0125] Figure 6FIG. 1 is a top view of a touch panel 100 according to some embodiments of the present invention. In this embodiment, the touch panel 100 further includes a shielding wire 160 disposed in the peripheral area PA. The shielding wire 160 mainly surrounds the touch sensing electrode TE and the peripheral lead 120, and the shielding wire 160 extends to the bonding area and is electrically connected to the ground terminal of the flexible printed circuit board. Therefore, the shielding wire 160 can shield or eliminate signal interference or electrostatic discharge (ESD) protection, especially the tiny current change caused by the human hand touching the connecting wires around the touch device.

[0126] The shielding wire 160 can be made of the modified metal nanowire 190, and the description of the peripheral lead 120 or the mark 140 can be referred to. In some embodiments of the present invention, the shielding wire 160, the peripheral lead 120 and the mark 140 can be made of the modified metal nanowire 190 and the film layer 130 of the same layer, and the metal nanowire 190 (such as the nanosilver wire layer) can be modified according to the aforementioned process to have a coating structure 180, and the specific method can refer to the aforementioned implementation method; the touch sensing electrode TE is made of the unmodified metal nanowire layer NWL.

[0127] Figure 7 Another embodiment of the single-sided touch panel 100 of the present invention is shown, which is a single-sided bridge touch panel. The difference between this embodiment and the above embodiment is at least that the touch sensing electrodes TE formed by the transparent conductive layer (i.e., the metal nanowire layer NWL) formed on the substrate 110 after the above patterning step may include: first touch sensing electrodes TE1 arranged along the first direction D1, second touch sensing electrodes TE2 arranged along the second direction D2, and connecting electrodes CE electrically connecting two adjacent first touch sensing electrodes TE1, that is, the first touch sensing electrodes TE1, the second touch sensing electrodes TE2, and the connecting electrodes CE are made of unmodified metal nanowires 190 and the film layer 130. In addition, the insulating block 164 can be disposed on the connecting electrode CE, for example, the insulating block 164 is formed of silicon dioxide; and the bridging wire 162 is further disposed on the insulating block 164, for example, the bridging wire 162 is formed of materials such as copper / ITO / metal nanowires, and the bridging wire 162 is connected to two adjacent second touch sensing electrodes TE2 in the second direction D2, and the insulating block 164 is located between the connecting electrode CE and the bridging wire 162 to electrically isolate the connecting electrode CE and the bridging wire 162, so that the touch electrodes in the first direction D1 and the second direction D2 are electrically isolated from each other.

[0128] In addition, after the metal nanowire layer NWL in the peripheral area PA has been patterned and modified, the modified metal nanowires 190 and the film layer 130 can be used to make peripheral leads 120 , which are electrically connected to the first touch sensing electrodes TE1 and the second touch sensing electrodes TE2 to transmit signals.

[0129] For specific methods, please refer to the previous article and I will not go into details here.

[0130] The metal nanowire modification method of the present invention can be applied to manufacture sensing electrodes that do not need to consider transmittance, such as touch pads of notebook computers (but not limited to them), antenna structures, coils for wireless charging, etc. Specifically, the method for making the sensing electrode includes: arranging an unmodified metal nanowire 190 on the substrate 110 to form a metal nanowire layer NWL on the substrate 110; then arranging a film layer 130 on the unmodified metal nanowire 190, so that the film layer 130 covers the unmodified metal nanowire 190, and the film layer 130 is in a pre-cured or uncured state; then patterning is performed to form a metal nanowire layer NWL with a pattern to make a sensing electrode for sensing a touch position / touch gesture; then a modification step is performed to form a coating structure 180 on the aforementioned metal nanowire 190, so that the metal nanowire layer NWL with the pattern is modified, that is, due to the aforementioned modification step, the sensing electrode for sensing the touch position / touch gesture is composed of the modified metal nanowire 190. Similar to the above-mentioned embodiment, the coating structure 180 may have the same or similar structural appearance as the metal nanowire 190, and the film layer 130 may be filled between adjacent metal nanowires 190. Since the touch pad, antenna structure, wireless charging coil and other objects of the notebook computer do not need to be light-transmissive, the modified metal nanowire 190 may be used to make the sensing electrode.

[0131] The sensing electrode of this embodiment can be connected to the wiring to connect to the external circuit to transmit the signal. The wiring of this embodiment can be equivalent to the aforementioned peripheral lead 120, and is also composed of the modified metal nanowire 190; in another embodiment, the wiring can be made of other conductive materials, such as silver wiring, copper wiring, etc.

[0132] In another embodiment, the modification step and the patterning step can be performed in an order that is mutually adjusted.

[0133] The specific implementation methods of the above steps can be found in the previous text.

[0134] The metal nanowire modification method of the present invention can be applied to make electrode plates that do not require patterns, such as cathode plates / anode plates of batteries (but not limited thereto). Specifically, the method for making the electrode plate includes: arranging unmodified metal nanowires 190 on the substrate 110 to form a metal nanowire layer NWL on the substrate 110; then arranging a film layer 130 on the unmodified metal nanowires 190, so that the film layer 130 covers the unmodified metal nanowires 190, and the film layer 130 is in a pre-cured or uncured state; then performing a modification step, forming a coating structure 180 on the aforementioned metal nanowires 190, so that the metal nanowire layer NWL is modified, that is, due to the aforementioned modification step, the entire surface of the electrode plate on the substrate is composed of the modified metal nanowires 190. As in the aforementioned embodiment, the coating structure 180 can have the same or similar structural appearance as the metal nanowires 190, and the film layer 130 will be filled between adjacent metal nanowires 190.

[0135] The electrode plate of this embodiment can be connected to the wiring to connect to the external circuit to transmit signals. The wiring of this embodiment can be equivalent to the aforementioned peripheral lead 120, and is also composed of the modified metal nanowire 190; in another embodiment, the wiring can be made of other conductive materials, such as silver wiring, copper wiring, etc.

[0136] The specific implementation methods of the above steps can be found in the previous text.

[0137] In some embodiments, the touch panel 100 / sensing electrode / electrode plate described herein can be manufactured by a roll-to-roll process. The roll-to-roll coating process uses conventional equipment and can be fully automated, which can significantly reduce the cost of manufacturing touch panels. The specific process of roll-to-roll coating is as follows: First, a flexible substrate 110 is selected, and the tape-shaped substrate 110 is installed between two rollers, and the rollers are driven by a motor so that the substrate 110 can be processed continuously along the movement path between the two rollers. For example, a slurry containing metal nanowires 190 is deposited on the surface of the substrate 110 using a storage tank, a spray device, a brush coating device and the like to form metal nanowires 190; a polymer is deposited on the surface of the substrate 110 using a spray head, and the polymer is cured into a film layer 130, patterned and modified, etc. Subsequently, the completed touch panel 100 is rolled out by the roller at the end of the production line to form a touch sensor tape.

[0138] The touch sensor roll of the present embodiment may further include the above-mentioned protective layer 150 , which fully covers the uncut touch panels 100 on the touch sensor roll. That is to say, the protective layer 150 may cover the uncut touch panels 100 on the touch sensor roll and then be cut and separated into individual touch panels 100 .

[0139] In some embodiments of the present invention, the substrate 110 is preferably a transparent substrate, specifically, a hard transparent substrate or a flexible transparent substrate, and its material can be selected from glass, polymethylmethacrylate (PMMA), polyvinyl chloride (PVC), polypropylene (PP), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), polystyrene (PS), cycloolefin polymers (COP), colorless polyimide (CPI), cycloolefin copolymer (COC), etc. In order to improve the adhesion between the substrate 110 and the metal nanowires 190, the substrate 110 can be preferably subjected to a pre-treatment step, such as a surface modification process, or an additional adhesive layer or resin layer is coated on the surface of the substrate 110.

[0140] In some embodiments of the present invention, the metal nanowire 190 may be a silver nanowire or silver nanofiber, 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 nanowire 190 may be between 70 nanometers and 80 nanometers, and the length may be about 8 micrometers.

[0141] Roll-to-roll production lines can adjust the order of multiple coating steps along the substrate's path as needed or incorporate any number of additional stations as needed. For example, pressure rollers or plasma equipment can be installed in the production line to achieve appropriate post-treatment processes.

[0142] The touch panel of the embodiment of the present invention can be assembled with other electronic devices, such as a display with a touch function. For example, the substrate 110 can be attached to a display component, such as a liquid crystal display component or an organic light emitting diode (OLED) display component, and the two can be attached with optical glue or other similar adhesives; and the touch sensing electrode TE can also be attached with an outer cover layer (such as protective glass) using optical glue. The touch panel, antenna, etc. of the embodiment of the present invention can be applied to electronic devices such as portable phones, tablet computers, and laptop computers, and flexible products can also be applied. The touch panel of the embodiment of the present invention can also be made on a polarizer. The electrodes of the embodiment of the present invention can also be made on wearable devices (such as watches, glasses, smart clothes, smart shoes, etc.) and automotive devices (such as dashboards, driving recorders, car rearview mirrors, car windows, etc.).

[0143] Other details of this embodiment are roughly the same as those described in the above embodiment and will not be repeated here.

[0144] The structures of different embodiments of the present invention may be referenced to each other and are not limited to the above-mentioned specific implementation modes.

[0145] In some embodiments of the present invention, the metal nanowires 190 are modified so that the modified metal nanowires 190 have better conductive properties than those before the modification.

[0146] In some embodiments of the present invention, by directly manufacturing the modified metal nanowires 190 into peripheral leads and / or marks, the error space reserved in the alignment process can be eliminated, thereby effectively reducing the width of the peripheral area.

[0147] In some embodiments of the present invention, the conductive nanostructures on one or both sides of the substrate may be modified.

[0148] In some embodiments of the present invention, additive processing (ie, directly performing processing on the conductive nanostructure) is used instead of subtractive processing, thereby improving process efficiency and reducing material costs.

[0149] Some embodiments of the present invention may be applied to flexible conductive substrates.

[0150] In some embodiments of the present invention, the exposed surface of the metal nanowire 190 is fully covered by the coating structure, that is, there is a coating structure between the metal nanowire and the film layer.

[0151] In some embodiments of the present invention, the coating structure is not stacked on the metal nanowire layer in a layered or blocky manner, but is affected by the initial shape of the metal nanowire, uses the metal nanowire as a seed, and is limited by the film layer to grow uniformly along the interface between the metal nanowire and the film layer.

[0152] In some embodiments of the present invention, the film layer serves as a limiting layer to limit / control the growth of the coating structure along the exposed surface of the metal nanowire 190. Due to the limiting layer, the coating structure can be uniformly grown on the exposed surface of the metal nanowire 190.

[0153] In some embodiments of the present invention, the growth of the coating structure is controllable and uniform.

[0154] Although the present invention has been disclosed in various embodiments as above, they are not intended to limit the present invention. Anyone skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the scope of the attached patent application.

Claims

1. A touch panel, characterized in that: The invention comprises: a substrate, wherein the substrate has a display area and a peripheral area; a peripheral lead, which is arranged in the peripheral area of ​​the substrate; and a touch sensing electrode, which is arranged in the display area of ​​the substrate, and the touch sensing electrode is electrically connected to the peripheral lead, wherein the peripheral lead and the touch sensing electrode include a plurality of conductive nanostructures and a film layer applied to the conductive nanostructures, and the interface between the conductive nanostructures in the peripheral lead and the film layer substantially has a coating structure; Wherein, the film layer has an uncured state, the coating structure is formed along the surface of the conductive nanostructure and is located at the interface between the conductive nanostructure and the film layer, and in the uncured state, the film layer has a first layer region and a second layer region, the curing state of the second layer region is higher than the curing state of the first layer region; in the first layer region, the coating structure is formed along the surface of the conductive nanostructure and is located at the interface between the conductive nanostructure and the film layer.

2. The touch panel according to claim 1, characterized in that: The coating structure comprises a coating layer, and the coating layer completely covers the interface between the conductive nanostructure and the film layer.

3. The touch panel according to claim 1, characterized in that: The film layer is filled between adjacent conductive nanostructures, and there is no separate coating structure in the film layer.

4. The touch panel according to claim 1, characterized in that: The conductive nanostructure comprises metal nanowires, and the coating structure completely covers the interface between the metal nanowires and the film layer, and forms a uniform coating layer on the interface.

5. The touch panel according to claim 1, characterized in that: The coating structure is a layered structure, an island-shaped protrusion structure, a point-shaped protrusion structure, or a combination of a layered structure, an island-shaped protrusion structure, and a point-shaped protrusion structure made of a conductive material. 6 . The touch panel according to claim 5 , wherein the conductive material is silver, gold, copper, nickel, platinum, iridium, rhodium, palladium, osmium or an alloy thereof.

7. The touch panel according to claim 1, characterized in that: The coating structure is a single-layer structure made of a single metal material or alloy material; or the coating structure is a two-layer or multi-layer structure made of two or more metal materials or alloy materials.

8. The touch panel according to claim 1, characterized in that: The coating structure is a chemically plated copper layer, an electroplated copper layer, a chemically plated copper-nickel layer, a chemically plated silver layer or a combination thereof.

9. A method for manufacturing a touch panel, characterized in that: The method comprises: providing a substrate having a display area and a peripheral area; arranging a conductive nanostructure in the display area and the peripheral area to form a conductive layer; applying a film layer on the conductive layer, and making the film layer reach a pre-cured or uncured state; The patterning step includes: patterning the conductive nanostructure and the film layer in the display area to form a touch sensing electrode and patterning the conductive nanostructure and the film layer in the peripheral area to form a peripheral lead, wherein the touch sensing electrode is electrically connected to the peripheral lead; and performing a modification step to form a coating structure on the surface of the conductive nanostructure of the peripheral lead, so that the interface between the conductive nanostructure and the film layer substantially has the coating structure; Among them, adding a film layer on the conductive layer includes: coating a polymer on the conductive layer; controlling the curing conditions to make the polymer reach a pre-cured or uncured state, the pre-cured or uncured film layer has a first layer area and a second layer area, the curing state of the second layer area is higher than the curing state of the first layer area, and in the first layer area, the coating structure is formed along the surface of the conductive nanostructure and is located at the interface between the conductive nanostructure and the film layer.

10. The method for manufacturing a touch panel according to claim 9, characterized in that: The modification step includes: immersing the film layer and the conductive nanostructure in a chemical plating solution, wherein the chemical plating solution penetrates into the film layer and contacts the conductive nanostructure, so that the metal is precipitated on the surface of the conductive nanostructure.

11. The method for manufacturing a touch panel according to claim 10, characterized in that: The coating structure is formed along the surface of the conductive nanostructure and is located at the interface between the conductive nanostructure and the film layer.

12. The method for manufacturing a touch panel according to claim 9, characterized in that: Adding a film layer on the conductive layer includes: coating a polymer on the conductive layer; controlling the curing conditions to make the polymer reach a pre-cured or uncured state.

13. The method for manufacturing a touch panel according to claim 9, characterized in that: Controlling the curing conditions includes introducing a gas and controlling the concentration of the gas in the first layer region and the second layer region.

14. The method for manufacturing a touch panel according to claim 9, characterized in that: The modification step includes: a chemical plating step, an electroplating step or a combination thereof.

15. The method for manufacturing a touch panel according to claim 9, characterized in that: The modification step is performed only in the peripheral zone.

16. The method for manufacturing a touch panel according to claim 9, characterized in that: Before the modification step, a step of shielding the display area is further included.

17. A device comprising the touch panel according to claim 1.

18. The device according to claim 17, characterized in that The device includes a display, a portable phone, a tablet computer, a wearable device, a car device, a notebook computer or a polarizing film.

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