Conductive film, preparation method thereof and touch panel

Abstract

The invention relates to a conductive film, a preparation method thereof and a touch panel. The conductive film includes: a substrate; the conductive layer is located on one side of the substrate, the conductive layer comprises a nano metal wire network and a protective layer filled in gaps of the nano metal wire network, and the thickness of the nano metal wire network is larger than or equal to that of the protective layer; and the etching site particles are embedded into the conductive layer in a semi-embedding mode and protrude out of the surface, away from the substrate, of the conductive layer. According to the conductive film adopting the technical scheme, in the wet etching process, when etching site particles of the conductive film are dissolved or fall off to form a tiny pit structure, a lateral penetration dimension is added in the wet etching process, and the problem that the nano metal wire conductive film is uneven in etching is effectively solved.

Description

Technical Field

[0001] The present invention relates to the field of touch technology, and in particular to a conductive film and a preparation method thereof, and a touch panel. Background Art

[0002] In recent years, breakthroughs in nano silver wire material technology have made nano silver wire conductive films widely used in the field of touch display due to their simple preparation process and flexural resistance.

[0003] At present, the industry generally chooses the laser etching process in the electrode pattern processing of the nanosilver wire conductive film. The laser etching process only disconnects the touch channel area and dummy area of ​​the nanosilver wire conductive film, and only removes about 5% of the nanosilver wire layer on the conductive film. Therefore, it cannot solve the white and foggy appearance of the touch module due to the surface scattering of the nanosilver wire and the production efficiency problem. The yellow light wet etching can remove more than 90% of the nanosilver wire layer on the conductive film by hollowing out the electrode pattern and dummy area on the nanosilver wire conductive film, which can perfectly solve the problems faced by the above laser etching electrode pattern. However, the protective layer of the nanosilver wire conductive film is a polymer material. Due to the inconsistent thickness or curing during the coating process and the acid and alkali resistance of the material itself, there is an uneven etching problem during the wet etching process. Summary of the invention

[0004] Based on this, it is necessary to provide a conductive film and a preparation method thereof and a touch panel in order to improve the problem of uneven etching of the nanometal wire conductive film.

[0005] A conductive film, comprising:

[0006] substrate;

[0007] a conductive layer, located on one side of the substrate, the conductive layer comprising a nanometal wire network and a protective layer filled in gaps of the nanometal wire network, the thickness of the nanometal wire network being greater than or equal to the thickness of the protective layer; and

[0008] The etching site particles are embedded in the conductive layer in a semi-embedded manner and protrude out of the conductive layer away from the surface of the substrate.

[0009] When the conductive film using the technical solution of the present invention is wet-etched, when the etching site particles of the conductive film dissolve or fall off to form a tiny pit structure, a lateral penetration dimension is added during the wet etching process, effectively improving the problem of uneven etching of the nanometal wire conductive film.

[0010] In one possible implementation, the etch site particles include at least one of silicon dioxide nanoparticles, zinc oxide nanoparticles, aluminum oxide nanoparticles, copper oxide nanoparticles, iron oxide nanoparticles, silver oxide nanoparticles, copper nanoparticles, silver nanoparticles, and iron nanoparticles.

[0011] In a feasible implementation, the size of the etching site particles is 50 nm to 1000 nm; and / or

[0012] The distribution density of the etching site particles is 3 to 10 per 10,000 square microns.

[0013] In a feasible implementation, the nanometal wire network includes a plurality of nanometal wires distributed in a mesh shape, and the nanometal wires include at least one of nanosilver wires, nanogold wires, nanocopper wires, nanoplatinum wires, nanoaluminum wires, nanotitanium wires, and nanotin wires.

[0014] In a feasible implementation, the thickness of the nanometal wire network is 70 nm to 150 nm.

[0015] In a feasible implementation, the thickness of the protective layer is 60% to 100% of the thickness of the nanometal wire network; and / or

[0016] The protective layer is a polymer protective layer.

[0017] In a feasible implementation, the material of the substrate includes one or more combinations of polyester, cycloolefin polymer, colorless polyimide, polypropylene, polyethylene, triacetate, PETG, TPU, PVA and PC.

[0018] In a feasible implementation, the light transmittance of the conductive film is greater than or equal to 80%; and / or

[0019] The sheet resistance of the conductive film is 5Ω / □ to 50Ω / □; and / or

[0020] The haze of the conductive film is 3.0% to 10.0%; and / or

[0021] The conductive film has a dyne value greater than 32.

[0022] A method for preparing a conductive film comprises the following steps:

[0023] Applying nanometal wire ink on one side of the substrate to form a nanometal wire network after drying; and

[0024] A protective liquid is applied on a side of the nanometal wire network away from the substrate, and a conductive film is obtained after curing; the conductive film comprises a substrate and a conductive layer located on one side of the substrate, the conductive layer comprises a nanometal wire network and a protective layer filled in the gaps of the nanometal wire network, and the thickness of the nanometal wire network is greater than or equal to the thickness of the protective layer;

[0025] Wherein, etching site particles are dispersed in the nanometal wire ink and / or the protective liquid, and in the conductive film, the etching site particles are embedded in the conductive layer in a semi-embedded manner and protrude from the conductive layer away from the surface of the substrate.

[0026] The preparation method of the conductive film of the technical solution of the present invention has a simple process. During the process of preparing the conductive film by wet etching, when the etching site particles of the conductive film dissolve or fall off to form a tiny pit structure, a lateral penetration dimension is added during the wet etching process, which effectively improves the problem of uneven etching of the nanometal wire conductive film.

[0027] A touch panel comprises any one of the above conductive films or a conductive film prepared by the above conductive film preparation method.

[0028] In the touch panel using the technical solution of the present invention, during the wet etching of the conductive film, when the etching site particles of the conductive film dissolve or fall off to form a tiny pit structure, a lateral penetration dimension is added during the wet etching process, effectively improving the problem of uneven etching of the nanometal wire conductive film. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic diagram of a conductive film according to one embodiment of the present invention;

[0030] Figure 2 is a flow chart of a method for preparing a conductive film according to one embodiment of the present invention;

[0031] Figure 3 This is a microscope photograph of a grid pattern of the conductive film of Example 1 of the present invention after yellow light wet etching;

[0032] Figure 4 This is a microscope photograph of the conductive film of Example 2 of the present invention;

[0033] Figure 5 This is a two-dimensional photograph of a grid pattern of the conductive film of Example 2 of the present invention after yellow light wet etching;

[0034] Figure 6 This is a microscope photograph of a grid pattern of the conductive film of Example 3 of the present invention after yellow light wet etching;

[0035] Figure 7This is a microscope photograph of a grid pattern of the conductive film of Example 4 of the present invention after yellow light wet etching;

[0036] Figure 8 This is a two-dimensional photograph of a grid pattern of the conductive film of Comparative Example 1 of the present invention after yellow light wet etching. DETAILED DESCRIPTION

[0037] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0039] See also Figure 1 , a conductive film 100 according to an embodiment of the present invention includes a substrate 110 , a conductive layer 120 and etching site particles 130 .

[0040] The conductive layer 120 is located on one side of the substrate 110, and includes a nanometal wire network 121 and a protective layer 122 filled in the gaps of the nanometal wire network 121. The thickness of the nanometal wire network 121 is greater than or equal to the thickness of the protective layer 122. The nanometal wire network 121 is a network conductive structure composed of multiple nanometal wires.

[0041] The etching site particles 130 are embedded in the conductive layer 120 in a semi-embedded manner, and protrude from the conductive layer 120 away from the surface of the substrate 110. The etching site particles 130 have the function of increasing the surface roughness of the conductive film 100, improving the dyne value of its surface, facilitating the adhesion of the conductive film 100 to the photoresist, photosensitive dry film or OCA glue, and also facilitating the wetting of alkaline and acidic solutions during the etching process, further improving the etching uniformity.

[0042] The conductive film 100 of this embodiment can be wet-etched. Since the protective layer 122 is usually a polymer material, due to the problem of inconsistent thickness or curing during the coating process and the acid and alkali resistance of the material itself, the wet etching process is not conducive to the forward penetration of the etching solution, resulting in uneven etching. During the wet etching process of the conductive film 100 of this embodiment, when the etching site particles 130 of the conductive film 100 are dissolved or detached to form a tiny pit structure, a lateral penetration dimension is added during the wet etching process, which effectively improves the problem of uneven etching of the nanometal wire conductive film 100.

[0043] On the basis of the above-mentioned embodiment, the etching site particles 130 include at least one of silicon dioxide nanoparticles, zinc oxide nanoparticles, aluminum oxide nanoparticles, copper oxide nanoparticles, iron oxide nanoparticles, silver oxide nanoparticles, copper nanoparticles, silver nanoparticles and iron nanoparticles. Since these etching site particles 130 are in a semi-embedded structure on the conductive layer 120, the exposed part is more likely to react with the alkaline substance or acidic substance in the yellow light wet etching process, and partially dissolve or fall off to form etching sites, which can ensure uniform etching of the conductive layer 120. Among them, the reaction equations of silicon dioxide nanoparticles, zinc oxide nanoparticles and aluminum oxide nanoparticles with alkaline solution are as follows:

[0044] SiO2+2NaOH+H2O=Na2SiO3+2H2O;

[0045] ZnO+2NaOH=Na2ZnO2+H2O;

[0046] Al2O3+2NaOH+3H2O=2K[Al(OH)4](sodium tetrahydroxyaluminate).

[0047] Based on the above embodiments, the shape of the etching site particles 130 includes but is not limited to sphere, rod, cube, polyhedron, core-shell and hollow microsphere structure.

[0048] Based on the above embodiments, the etching site particles 130 can be dispersed in a water-based or solvent-based system after being physically or chemically modified.

[0049] On the basis of the above-mentioned embodiment, the size of the etching site particle 130 is 50nm to 1000nm. The test data of the optical thickness gauge shows that the thickness of the conductive layer 120 with a square resistance of 5Ω to 30Ω is between 90 and 110nm. The square resistance is more closely related to the distribution density of the nanometal wire network 121. Taking the silver wire conductive film with a diameter of 20 to 30nm as an example, the area covered by the nanosilver wire with a square resistance of 30Ω / □, 10Ω / □ and 5Ω / □ on the substrate 110 is approximately 13%, 23% and 40% respectively. Therefore, the size of the etching site particle 130 is between 50nm and 1000nm, and it can be ensured that it is half-embedded in the nanometal wire conductive layer 120 to form an etching site during its coating process. When the size of the etching site particle 130 is small, it reacts with the alkaline or acidic solution to dissolve to form an etching site. When the size of the etching site particle 130 is large, the contact between it and the nanometal wire conductive layer 120 is weakened by the alkaline or acidic solution reaction, so that it falls off to form an etching site. Further, the size of the etching site particle 130 can be, but is not limited to, 50nm, 100nm, 200nm, 300nm, 400nm, 500nm, 600nm, 700nm, 800nm, 900nm or 1000nm.

[0050] On the basis of the above-mentioned embodiment, the distribution density of the etching site particles 130 is 3 to 10 per 10,000 square microns. Since the optical performance of the touch pattern is improved when the conductive film 100 is wet-etched, the touch pattern is hollowed out and designed with a grid pattern, so that the duty cycle of the nanometal wire conductive layer 120 on the substrate 110 reaches more than 90%. Usually, the size of a single grid is between 10,000 square microns and 50,000 square microns, and the line width of the grid conductive pattern is between 5um and 30um. Therefore, the distribution density of the etching site particles 130 is between 3 and 10 per 10,000 square microns, which can ensure uniform etching of the grid pattern occupancy area while reducing the influence of the etching site particles 130 on the conductivity of the grid pattern.

[0051] On the basis of the foregoing implementation, the nanometal wire network 121 includes a plurality of mesh-distributed nanometal wires, wherein the nanometal wires include at least one of nanosilver wires, nanogold wires, nanocopper wires, nanoplatinum wires, nanoaluminum wires, nanotitanium wires and nanotin wires.

[0052] Based on the above-mentioned embodiment, the thickness of the nanometal wire network 121 is 70 nm to 150 nm.

[0053] On the basis of the above-mentioned embodiment, the thickness of the protective layer 122 is 60% to 100% of the thickness of the nanometal wire network 121. Within this range, the adhesion of the nanometal wire network 121 on the substrate 110 can be guaranteed, and sufficient etching sites can be ensured in the nanometal wire network 121 itself. Further, the thickness of the protective layer 122 can be, but is not limited to, 60%, 70%, 80%, 90% or 100% of the thickness of the nanometal wire network 121. Further, the thickness of the protective layer 122 is 80% to 100% of the thickness of the nanometal wire network 121; further, the thickness of the protective layer 122 is 80% to 90% of the thickness of the nanometal wire network 121. This is more conducive to the straightness of the grid pattern lines after the nanometal wire conductive layer 120 is wet-etched by yellow light.

[0054] Based on the above-mentioned embodiment, the protective layer 122 is a polymer protective layer, which may include but is not limited to one or more of aliphatic polyurethane acrylate, aromatic polyurethane acrylate, polyurethane methacrylate, diallyl phthalate, epoxy acrylate and epoxy methacrylate.

[0055] Based on the above-mentioned embodiment, the material of the substrate 110 includes one or more combinations of polyester, cycloolefin polymer (COP), colorless polyimide (CPI), polypropylene (PP), polyethylene (PE), triacetate (TCA), poly(ethylene terephthalateco-1,4-cylclohexylenedimethylene terephthalate) (PETG), thermoplastic polyurethane (TPU), polyvinyl alcohol (PVA), and polycarbonate (PC).

[0056] Based on the foregoing embodiments, the transmittance of the conductive film 100 is greater than or equal to 80%, the square resistance of the conductive film 100 is 5Ω / □~50Ω / □, the haze of the conductive film 100 is 3.0%~10.0%, and the dyne value of the conductive film 100 is greater than 32.

[0057] On the basis of the foregoing embodiments, wet etching includes but is not limited to at least one of oxidative etching and acid etching. In some embodiments, the etching solution may include but is not limited to hydrochloric acid-nitric acid system etching solution, ferric chloride system etching solution, ferric nitrate system etching solution, ferric nitrate-nitric acid system etching solution and phosphoric acid-nitric acid-acetic acid system etching solution.

[0058] When the conductive film using the technical solution of the present invention is wet-etched, when the etching site particles of the conductive film dissolve or fall off to form a tiny pit structure, a lateral penetration dimension is added during the wet etching process, effectively improving the problem of uneven etching of the nanometal wire conductive film.

[0059] See also Figure 2 A method for preparing a conductive film according to an embodiment of the present invention comprises the following steps:

[0060] S10, coating nanometal wire ink on one side of the substrate, and forming a nanometal wire network after drying.

[0061] S20, applying a protective liquid on the side of the nanometal wire network away from the substrate, and obtaining a conductive film after curing; the conductive film includes a substrate and a conductive layer located on one side of the substrate, the conductive layer includes a nanometal wire network and a protective layer filled in the gaps of the nanometal wire network, and the thickness of the nanometal wire network is greater than or equal to the thickness of the protective layer. Wherein, etching site particles are dispersed in the nanometal wire ink and / or the protective liquid, and in the conductive film, the etching site particles are embedded in the conductive layer in a semi-embedded manner and protrude from the surface of the conductive layer away from the substrate.

[0062] In a feasible implementation, the etching site particles can be dispersed in the nanometal wire ink or the protective liquid to complete the coating together. In some embodiments, the modified etching site particles are dispersed in the nanometal wire ink, and the nanometal wire ink is first coated on the substrate to form a composite structure of the nanometal wire network and the etching site particles, and then the OC protective liquid is coated, and a wet-etchable conductive film is obtained after curing. In some embodiments, the modified etching site particles are dispersed in the OC protective liquid, and the metal nanowire ink is first coated on the substrate to form a nanometal wire network, and then the OC protective liquid containing the modified etching site particles is coated to form an etching site structure on the nanometal wire network, and finally a wet-etchable conductive film is obtained.

[0063] In a feasible implementation, the protective liquid may include, but is not limited to, one or more of aliphatic polyurethane acrylate, aromatic polyurethane acrylate, polyurethane methacrylate, diallyl phthalate, epoxy acrylate and epoxy methacrylate.

[0064] The preparation method of the conductive film of the technical solution of the present invention has a simple process. During the process of preparing the conductive film by wet etching, when the etching site particles of the conductive film dissolve or fall off to form a tiny pit structure, a lateral penetration dimension is added during the wet etching process, which effectively improves the problem of uneven etching of the nanometal wire conductive film.

[0065] A touch panel according to an embodiment includes any one of the above conductive films or a conductive film prepared by the above conductive film preparation method.

[0066] In the touch panel using the technical solution of the present invention, during the wet etching of the conductive film, when the etching site particles of the conductive film dissolve or fall off to form a tiny pit structure, a lateral penetration dimension is added during the wet etching process, effectively improving the problem of uneven etching of the nanometal wire conductive film.

[0067] With reference to the above implementation contents, in order to make the technical solution of the present invention more specific, clear and easy to understand, the technical solution of the present invention is now exemplified. However, it should be noted that the contents to be protected by the present invention are not limited to the following embodiments.

[0068] Example 1

[0069] This embodiment provides a wet-etchable conductive film and a method for preparing the same. Figure 1 As shown, the conductive film 100 includes a substrate 110, a conductive layer 120 and etching site particles 130. The conductive layer 120 is located on one side of the substrate 110, and the conductive layer 120 includes a nanometal wire network 121 and a protective layer 122 filled in the gaps of the nanometal wire network 121, and the thickness of the nanometal wire network 121 is greater than or equal to the thickness of the protective layer 122. The etching site particles 130 are embedded in the conductive layer 120 in a semi-embedded manner, and protrude from the conductive layer 120 away from the surface of the substrate 110.

[0070] In this embodiment, the substrate 110 is a flexible PET with a thickness of 125 μm.

[0071] In this embodiment, the nanometal wire network 121 includes a plurality of nanometal wires distributed in a mesh shape. The nanometal wires are nanosilver wires. The diameter of the nanosilver wires is about 25 nm and the length is about 10 μm to 20 μm. The thickness of the nanometal wire network 121 is about 90 nm.

[0072] In this embodiment, the material of the protection layer 122 is acrylic resin, and the theoretical coating dry thickness is 70 nm. The protection layer 122 is filled or embedded in the network gaps between the nano silver wires.

[0073] In this embodiment, the etching site particles 130 are nano zinc oxide particles with a size of 40 nm to 100 nm, which are dispersed in the protective solution after being modified.

[0074] The wet-etchable conductive film 100 of this embodiment is prepared by the following steps:

[0075] S11, prepare nano silver wire ink with a content of 0.3wt%, wherein the diameter of the nano silver wire is 25nm and the length is 10μm-20μm. Use slit coating to coat the nano silver wire ink on the PET substrate 110, and form a nano metal wire network 121 after drying. The dry thickness of the nano metal wire network 121 is about 95nm, and the square resistance is 8Ω / □~10Ω / □.

[0076] S12, physically modifying nano zinc oxide particles with a particle size of 40 nm to 100 nm so as to uniformly disperse them in a protective solution, wherein the protective solution contains 2.0 wt% of resin solids.

[0077] S13, using a slit coating method, the protective liquid prepared in step S12 is coated on the nano metal wire network 121 prepared in step S11, and then dried and cured to obtain a protective layer 122 of the composite nano zinc oxide etching site particles 130, the coating theoretical dry thickness of the protective layer 122 is 70nm, and the conductive film 100 of Example 1 is obtained, and the grid pattern thereof after yellow light wet etching is as shown Figure 3 As shown. Figure 3 It can be seen that the conductive film 100 of the present embodiment effectively improves the problem of uneven etching.

[0078] Example 2

[0079] This embodiment provides a wet-etchable conductive film and a method for preparing the same. Figure 1 As shown, the conductive film 100 includes a substrate 110 , a conductive layer 120 , and etching site particles 130 .

[0080] In this embodiment, the substrate 110 is a flexible PET with a thickness of 100 μm.

[0081] In this embodiment, the nanometal wire network 121 includes a plurality of nanometal wires distributed in a mesh shape. The nanometal wires are nanosilver wires. The diameter of the nanosilver wires is about 30 nm and the length is about 15 μm to 25 μm. The thickness of the nanometal wire network 121 is about 105 nm.

[0082] In this embodiment, the material of the protection layer 122 is acrylic resin, and the theoretical coating thickness is 80 nm. The protection layer 122 is filled or embedded in the network gaps between the nano silver wires.

[0083] In this embodiment, the etching site particles 130 are nano-silicon dioxide particles with a size of 60 nm to 120 nm, which are dispersed in the protective solution after being modified.

[0084] The wet-etchable conductive film 100 of this embodiment is prepared by the following steps:

[0085] S21, prepare nano silver wire ink with a content of 0.3wt%, wherein the nano silver wire has a diameter of 30nm and a length of 15μm to 25μm. Use slit coating to coat the nano silver wire ink on the PET substrate 110, and form a nano metal wire network 121 after drying. The dry thickness of the nano metal wire network 121 is about 105nm, and the square resistance is 4Ω / □ to 6Ω / □.

[0086] S22, physically modifying nano zinc oxide particles with a particle size of 60 nm to 120 nm so as to uniformly disperse them in a protective solution, wherein the protective solution contains 2.0 wt% of resin solids.

[0087] S23, using a slit coating method, the protective liquid prepared in step S22 is coated on the nano metal wire network 121 prepared in step S21, and then dried and cured to obtain a protective layer 122 of the composite nano silicon dioxide etching site particles 130, the coating theoretical dry thickness of the protective layer 122 is 80nm, and the conductive film 100 of Example 2 is obtained. The microscope photo of the conductive film 100 is as shown in FIG. Figure 4 As shown, the grid pattern after yellow light wet etching is as follows Figure 5 As shown. Figure 4 It can be seen that the surface of the conductive film 100 of this embodiment has etching site particles (i.e. Figure 4 from Figure 5 It can be seen that the conductive film 100 of the present embodiment effectively improves the problem of uneven etching.

[0088] Example 3

[0089] This embodiment provides a wet-etchable conductive film and a method for preparing the same. Figure 1 As shown, the conductive film 100 includes a substrate 110 , a conductive layer 120 , and etching site particles 130 .

[0090] In this embodiment, the substrate is flexible PET with a thickness of 125 μm.

[0091] In this embodiment, the nanometal wire network 121 includes a plurality of nanometal wires distributed in a mesh shape. The nanometal wires are nanosilver wires. The diameter of the nanosilver wires is about 35 nm and the length is about 20 μm to 30 μm. The thickness of the nanometal wire network 121 is about 120 nm.

[0092] In this embodiment, the material of the protection layer 122 is acrylic resin, and the theoretical coating thickness is 100 nm. The protection layer 122 is filled or embedded in the network gaps between the nano silver wires.

[0093] In this embodiment, the etching site particles 130 are silver nanoparticles with a size of 150 nm to 250 nm, which are dispersed in the nano silver wire ink after being modified.

[0094] The wet-etchable nano-metal wire conductive film 100 of this embodiment is prepared by the following steps:

[0095] S31, silver nanoparticles are physically modified and dispersed in a nanosilver wire ink with a content of 0.3wt%, wherein the nanosilver wire has a diameter of 35nm and a length of 20μm to 30μm. The nanosilver wire ink is coated on a PET substrate 110 by slit coating to obtain a nanometal wire network 121 of composite silver nanoparticles, which has a dry thickness of about 120nm and a square resistance of 4Ω / □ to 6Ω / □. The silver nanoparticles are randomly distributed in the nanometal wire network 121 to form a protruding structure.

[0096] S32, using a slit coating method, coating the protective liquid on the nano metal wire network 121 prepared in S31, and then drying and curing to obtain a protective layer 122, the theoretical dry thickness of the protective layer 122 coating is 100nm, and the conductive film 100 of Example 3 is obtained, and the grid pattern thereof after yellow light wet etching is as shown in Figure 6 As shown. Figure 6 It can be seen that the conductive film 100 of the present embodiment effectively improves the problem of uneven etching.

[0097] Example 4

[0098] This embodiment provides a wet-etchable conductive film and a method for preparing the same. Figure 1 As shown, the conductive film 100 includes a substrate 110 , a conductive layer 120 , and etching site particles 130 .

[0099] In this embodiment, the substrate 110 is a flexible PET with a thickness of 125 μm.

[0100] In this embodiment, the nanometal wire network 121 includes a plurality of nanometal wires distributed in a mesh shape. The nanometal wires are nanosilver wires. The diameter of the nanosilver wires is about 30 nm and the length is about 15 μm to 25 μm. The thickness of the nanometal wire network 121 is about 110 nm.

[0101] In this embodiment, the material of the protection layer 122 is acrylic resin, and the theoretical coating dry thickness is 90 nm. The protection layer 122 is filled or embedded in the network gaps between the nano silver wires.

[0102] In this embodiment, the etching site particles 130 are copper nanoparticles with a size of 60 nm to 150 nm, which are dispersed in the protective solution after being modified.

[0103] The wet-etchable conductive film 100 of this embodiment is prepared by the following steps:

[0104] S41, prepare nano silver wire ink with a content of 0.3wt%, wherein the nano silver wire has a diameter of 30nm and a length of 15μm to 25μm. Use slit coating to coat the nano silver wire ink on the PET substrate 100, and form a nano metal wire network 121 after drying. The dry thickness of the nano metal wire network 121 is about 110nm, and the square resistance is 4Ω / □ to 6Ω / □.

[0105] S42, physically modifying copper nanoparticles with a particle size of 60 nm to 150 nm so as to uniformly disperse them in a protective solution, wherein the protective solution contains 2.0 wt% of resin solids.

[0106] S43, using a slit coating method, the protective liquid prepared in step S42 is coated on the nano silver wire conductive layer prepared in step S41, and then dried and cured to obtain a protective layer 122 of the composite copper nanoparticle etching site particles 130, the coating theoretical dry thickness of the protective layer 122 is 90nm, and the conductive film 100 of Example 4 is obtained, and the grid pattern thereof after yellow light wet etching is as shown Figure 7 As shown. Figure 7 It can be seen that the conductive film 100 of the present embodiment effectively improves the problem of uneven etching.

[0107] Comparative Example 1

[0108] This comparative example is a comparative example of Example 2, and provides a wet-etchable conductive film and a preparation method thereof, and the only difference from Example 2 is that the conductive film only includes a substrate and a conductive layer located on one side of the substrate, and does not include etching site particles.

[0109] The wet-etchable conductive film of this embodiment is prepared by the following steps:

[0110] S21, prepare a nano silver wire ink with a content of 0.3wt%, wherein the nano silver wire has a diameter of 30nm and a length of 15μm to 25μm. Use a slit coating method to coat the nano silver wire ink on a PET substrate, and after drying, form a nano metal wire network, wherein the dry thickness of the nano metal wire network is about 105nm, and the square resistance is 4Ω / □ to 6Ω / □.

[0111] S22, preparing a protective solution, wherein the acrylic resin solid content in the protective solution is 2.0 wt%.

[0112] S23, using a slit coating method, the protective liquid prepared in step S22 is coated on the nano metal wire network prepared in step S21, and then dried and cured to obtain a protective layer 122, the coating theoretical dry thickness of the protective layer 122 is 80nm, and a conductive film of comparative example 1 is obtained. The conductive film is wet-etched by yellow light to form a grid pattern as shown in Figure 8 shown.

[0113] from Figure 8It can be seen that the conductive film of comparative example 1 obviously has the problem of uneven etching. Figure 5 ) and the grid pattern of the conductive film of Comparative Example 1 (i.e. Figure 8 ) by comparison, it can be seen that the conductive film of Example 2 contains etching site particles, which can effectively improve the problem of uneven etching.

[0114] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0115] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A conductive film, characterized in that: The conductive film comprises: substrate; a conductive layer, located on one side of the substrate, the conductive layer comprising a nanometal wire network and a protective layer filled in gaps of the nanometal wire network, the thickness of the nanometal wire network being greater than or equal to the thickness of the protective layer; and The etching site particles are embedded in the conductive layer in a semi-embedded manner and protrude out of the conductive layer away from the surface of the substrate.

2. The conductive film according to claim 1, characterized in that The etch site particles include at least one of silicon dioxide nanoparticles, zinc oxide nanoparticles, aluminum oxide nanoparticles, copper oxide nanoparticles, iron oxide nanoparticles, silver oxide nanoparticles, copper nanoparticles, silver nanoparticles, and iron nanoparticles.

3. The conductive film according to claim 1, characterized in that The size of the etching site particles is 50nm to 1000nm; and / or The distribution density of the etching site particles is 3 to 10 per 10,000 square microns.

4. The conductive film according to claim 1, characterized in that The nanometal wire network includes a plurality of nanometal wires distributed in a mesh shape, and the nanometal wires include at least one of nanosilver wires, nanogold wires, nanocopper wires, nanoplatinum wires, nanoaluminum wires, nanotitanium wires and nanotin wires.

5. The conductive film according to claim 1, characterized in that: The thickness of the nano metal wire network is 70nm-150nm.

6. The conductive film according to claim 1, characterized in that The thickness of the protective layer is 60% to 100% of the thickness of the nanometal wire network; and / or The protective layer is a polymer protective layer.

7. The conductive film according to claim 1, characterized in that The material of the substrate includes one or more combinations of polyester, cycloolefin polymer, colorless polyimide, polypropylene, polyethylene, triacetate, PETG, TPU, PVA and PC.

8. The conductive film according to claim 1, characterized in that The light transmittance of the conductive film is greater than or equal to 80%; and / or The sheet resistance of the conductive film is 5Ω / □ to 50Ω / □; and / or The haze of the conductive film is 3.0% to 10.0%; and / or The conductive film has a dyne value greater than 32.

9. A method for preparing a conductive film, characterized in that: The steps include: Applying nanometal wire ink on one side of the substrate to form a nanometal wire network after drying; and A protective liquid is applied on a side of the nanometal wire network away from the substrate, and a conductive film is obtained after curing; the conductive film comprises a substrate and a conductive layer located on one side of the substrate, the conductive layer comprises a nanometal wire network and a protective layer filled in the gaps of the nanometal wire network, and the thickness of the nanometal wire network is greater than or equal to the thickness of the protective layer; Wherein, etching site particles are dispersed in the nanometal wire ink and / or the protective liquid, and in the conductive film, the etching site particles are embedded in the conductive layer in a semi-embedded manner and protrude from the conductive layer away from the surface of the substrate.

10. A touch panel, characterized in that: A conductive film comprising the conductive film according to any one of claims 1 to 8 or a conductive film prepared by the conductive film preparation method according to claim 9.

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