Manufacturing method of capacitive touch screen and capacitive touch screen
Patent Information
- Application Number
- CN202510365175.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-26
- Publication Date
- 2026-09-29
AI Technical Summary
[0003]本发明实施例的目的在于：提供一种电容式触摸屏的制作方法及电容式触摸屏，其能够解决现有技术的电容式触摸屏存在的厚度厚、成本高的问题
[0010]本方案通过共用单层PET基材(氧化铟锡膜自带基材)，并利用金属网格直接在绝缘层沟槽中形成接收电极层，省去一层PET基材和一层OCA胶，显著降低结构厚度。发射电极层采用氧化铟锡制作，具有高抗氧化性和热稳定性，可有效抑制高温高湿环境下的金属离子迁移问题；接收电极层采用金属网格，金属网格作为阴极(低电势层)，在电场中受离子迁移影响较小，且其低方阻特性可提升触控灵敏度，因此本方案制备所得的电容式触摸屏具备稳定性好、寿命长的优点。
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Figure CN122837665A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of touch screen manufacturing processes, and more particularly to a method for manufacturing a capacitive touch screen and a capacitive touch screen. Background Technology
[0002] Currently, the commonly used stacked structure for capacitive touchscreens in the ultra-large interactive flat panel market is GFF: a layer of G (Glass, glass cover) + a layer of F (Film, a conductive film composed of a conductive layer and PET substrate, serving as the RX layer, i.e., the receiving layer) + another layer of F (serving as the TX layer, i.e., the transmitting layer). The three are bonded together with OCA (Optically Transparent Adhesive). The RX layer and TX layer need to be attached to two PET substrates respectively, resulting in a relatively thick GFF structure and a higher cost. Summary of the Invention
[0003] The purpose of this invention is to provide a method for manufacturing a capacitive touchscreen and a capacitive touchscreen in general, which can solve the problems of thick thickness and high cost of existing capacitive touchscreens.
[0004] To achieve the above objectives, this application adopts the following technical solution:
[0005] On the one hand, a method for manufacturing a capacitive touchscreen is provided, including the following steps:
[0006] Provide indium tin oxide film;
[0007] An electrode pattern is etched onto the indium tin oxide film to form an emission electrode layer;
[0008] An insulating layer with grid grooves is fabricated on the emitting electrode layer;
[0009] A metal mesh is fabricated in the mesh trenches of the insulating layer to form a receiving electrode layer.
[0010] This solution utilizes a single-layer PET substrate (with the indium tin oxide film itself as the substrate) and forms the receiving electrode layer directly in the insulating trench using a metal mesh, eliminating the need for a PET substrate layer and an OCA adhesive layer, thus significantly reducing the structural thickness. The transmitting electrode layer is made of indium tin oxide, which has high oxidation resistance and thermal stability, effectively suppressing metal ion migration under high temperature and humidity environments. The receiving electrode layer uses a metal mesh, which acts as a cathode (low potential layer), making it less affected by ion migration in an electric field. Furthermore, its low sheet resistance improves touch sensitivity. Therefore, the capacitive touchscreen fabricated using this solution possesses advantages such as good stability and long lifespan.
[0011] Optionally, before etching to form the emitter electrode layer, conductive metal is screen-printed and cured in the non-display area around the indium tin oxide film; during etching, the indium tin oxide film and the conductive metal are etched simultaneously to obtain the conductive lines that establish the connection and the emitter electrode layer.
[0012] By screen-printing conductive metal in the non-display area of the indium tin oxide (ITO) film and curing it, and then simultaneously etching the ITO layer and the conductive metal, the traditional process of step-by-step etching and multiple mask protection steps is eliminated, simplifying the process, improving efficiency, and reducing costs. Furthermore, after screen-printing the conductive metal in the non-display area, simultaneous etching achieves a seamless connection between the conductive lines and the emitter electrode layer, ensuring a precise and reliable connection between the conductive lines on the bezel and the emitter electrode layer.
[0013] Optionally, in the step of making the insulating layer, the grid grooves are formed by an imprinting process.
[0014] The imprinting process directly imprints grid trenches onto insulating material using a physical mold. The trench width and depth can be precisely controlled to the ±1μm level, effectively ensuring the orthogonal alignment accuracy (error <±3μm) between the metal grid (receiving electrode layer) and the indium tin oxide layer (emitting electrode layer), thus avoiding touch signal crosstalk. Furthermore, the sidewall steepness of the imprinted grid trenches can be >85°, effectively preventing lateral diffusion during metal filling and reducing the risk of short circuits. The imprinting process eliminates the need for photoresist coating, exposure and development, and chemical etching; the trench structure is directly formed through the mold, saving consumables such as photoresist and etching solution, reducing the cost per process by 20%-30%.
[0015] Optionally, after fabricating the emitter electrode layer, a hardened layer covering the emitter electrode layer is fabricated on the top surface of the indium tin oxide film, and then the insulating isolation layer is fabricated on the hardened layer.
[0016] The imprinting process requires applying pressure (usually 5-20 MPa) to the insulating layer material through a mold. This pressure will indirectly affect the underlying structure (i.e., the emitting electrode layer). In this solution, adding a hardener to the surface of the emitting electrode layer can effectively disperse the imprinting pressure and avoid the problem of microcracks or peeling of the indium tin oxide layer due to local stress concentration.
[0017] Optionally, in the step of making the insulating layer, a light-curing adhesive is first applied, followed by light curing and imprinting processes to obtain the insulating layer with the grid grooves.
[0018] Using UV-curable adhesive as the insulating layer in conjunction with the imprinting process, the UV-curable adhesive undergoes pre-curing under UV light, imprinting, and secondary curing, effectively shortening the time and improving efficiency. Furthermore, the low viscosity and high leveling properties of the UV-curable adhesive allow for precise filling of the micron-level grooves in the imprinting mold, minimizing replication errors.
[0019] Optionally, in the step of making the insulating layer, the photocuring and imprinting processes can be completed simultaneously in one process.
[0020] By adopting a single-process integration, the traditional process of "coating → pre-curing → imprinting → secondary curing" is eliminated, which simplifies the process and effectively improves production efficiency.
[0021] Optionally, the photocuring and imprinting process includes two photocuring stages. In the first photocuring stage, low-intensity light is used to semi-cur the colloid, and then the grid grooves are formed by imprinting. In the second photocuring stage, high-intensity light is used to completely cure the colloid.
[0022] By using a segmented curing method, high-precision, high-reliability, and high-efficiency manufacturing of the insulating layer was achieved, while ensuring the precision of the formed mesh grooves and improving the precision of the subsequent metal mesh production.
[0023] Optionally, the process of fabricating the receiving electrode layer includes the steps of: using a scraper to fill the mesh trench with metal slurry, and then curing the metal slurry to form the receiving electrode layer.
[0024] By employing a process that combines the application of metal slurry with curing, a metal mesh that is highly integrated with the mesh trenches can be obtained, ensuring both the reliability of the structure and the precision of the metal mesh.
[0025] Optionally, after completing the fabrication of the receiving electrode layer, the following steps can be performed:
[0026] Optical adhesive is bonded onto the receiving electrode layer;
[0027] Bond the flexible circuit board and bring out the internal circuitry;
[0028] Functional testing;
[0029] The protective panel is attached to the optical adhesive.
[0030] Bonding the flexible circuit board with optical adhesive to expose internal circuitry ensures stability and prevents the bonded circuit board from being affected by the bonding process. Performing functional testing before bonding the protective panel allows for timely detection and optimization of product defects, ensuring high product yield.
[0031] On the other hand, a capacitive touch screen is provided, which is manufactured according to the above-described method for manufacturing a capacitive touch screen.
[0032] The capacitive touchscreen manufactured using the method described in this application has the advantages of being thin, low-cost, highly reliable, and having a long lifespan. Attached Figure Description
[0033] The present application will now be described in further detail with reference to the accompanying drawings and embodiments.
[0034] Figure 1 This is a schematic diagram of the existing GFF stacked structure of a capacitive touchscreen;
[0035] Figure 2 This is a schematic diagram of the stacked structure of the capacitive touchscreen according to an embodiment of this application;
[0036] Figure 3 This is a flowchart illustrating a method for manufacturing a capacitive touchscreen according to an embodiment of this application.
[0037] In the picture:
[0038] 1. Substrate; 2. Emitter electrode layer; 3. Hardened layer; 4. Insulating layer; 5. Receiver electrode layer; 6. Optical adhesive; 7. Protective panel. Detailed Implementation
[0039] To make the technical problems solved by this application, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the embodiments of this application are further described in detail below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0040] In the description of this application, unless otherwise expressly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0041] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0042] like Figure 1 As shown, the commonly used stacked structure for capacitive touchscreens in the current ultra-large interactive flat panel market is GFF: a layer of G (Glass, glass cover) + a layer of F (Film, a conductive film composed of a conductive layer and a PET substrate, serving as the RX layer, i.e., the receiving layer) + another layer of F (serving as the TX layer, i.e., the transmitting layer). The three are bonded together with OCA (optical transparent adhesive). The RX layer and TX layer need to be attached to two layers of PET substrate, which results in the overall GFF structure being relatively thick and costly.
[0043] In order to solve the above problems, the inventors of this application considered whether it is possible to make the RX layer and TX layer share a single PET substrate, thereby eliminating the need for a PET substrate and an OCA structure, which would both reduce the overall thickness of the capacitive touch screen and lower the cost.
[0044] In light of the widespread application of conductive materials with metal mesh in capacitive touchscreens, the inventors of this application conceived of setting two layers of metal mesh on a PET substrate, with a transparent insulating material separating the two metal mesh layers. This allows the two metal mesh layers to serve as the RX layer and TX layer, respectively, thus achieving both the capacitive touchscreen structure and the aforementioned goal of eliminating the need for a PET substrate layer.
[0045] However, in practice, the inventors of this application discovered that due to the high reactivity of the metal mesh material, if the insulating layer between the RX and TX layers is made thin, the distance between the two metal mesh layers becomes too close. In certain high-temperature and high-humidity working environments, prolonged operation under power can easily lead to metal ion migration. Specifically, under the influence of an electric field, metal ions are affected by the electric field force and move from the anode (TX) to the cathode (RX). This migration can cause structural changes within the material. When sufficient changes accumulate, a short circuit will form between the two electrode layers, leading to touch function failure. Therefore, this type of structure still suffers from low reliability and short lifespan. On the other hand, if the insulating layer between the RX and TX layers is made thicker, it first presents problems such as high manufacturing difficulty and long curing time. More importantly, making the insulating layer thicker will increase the overall thickness of the capacitive screen, ultimately failing to achieve the goal of thinning the capacitive screen.
[0046] After numerous experiments and creative improvements, the inventors of this application have developed a method for manufacturing a capacitive touchscreen that can both reduce the thickness of the capacitive screen and avoid the problem of reduced reliability.
[0047] Specifically, such as Figure 2-3 As shown, the method for manufacturing a capacitive touchscreen provided in this embodiment includes the following steps:
[0048] S1. Provides an indium tin oxide film;
[0049] S2. Etching an electrode pattern onto the indium tin oxide film to form an emission electrode layer 2;
[0050] S3. An insulating layer 4 with grid grooves is formed on the emitting electrode layer 2;
[0051] S4. A metal mesh is formed in the mesh trench of the insulating isolation layer 4 to form a receiving electrode layer 5.
[0052] Specifically, the indium tin oxide (ITO) film structure consists of a PET substrate 1 and an ITO layer. In this design, the ITO film structure itself includes a substrate 1, eliminating the need for additional substrate 1 layers in subsequent processes. Electrode patterns are etched onto the ITO film to form the emitter electrode layer 2. Compared to the metal mesh, ITO offers superior oxidation resistance and thermal stability, making it less prone to ion migration even under high temperature and humidity conditions. Therefore, using the ITO layer as the emitter electrode layer 2 ensures its reliability and durability. The subsequently fabricated metal mesh serves as the receiver electrode layer 5. Compared to the emitter electrode layer 2, the receiver electrode layer 5 has a lower potential and acts as a cathode, thus minimizing the risk of metal ion migration.
[0053] The capacitive touchscreen manufacturing method provided in this embodiment achieves at least the following beneficial effects:
[0054] (1) Structural optimization and thickness reduction: Traditional GFF structures require two PET substrates 1 to support the RX and TX layers respectively, and are bonded together with OCA adhesive, resulting in an increase in overall thickness. This solution uses a single PET substrate 1 (the indium tin oxide film has its own substrate 1) and utilizes a metal mesh to directly form the receiving electrode layer 5 in the insulating layer trench, eliminating one PET substrate 1 and one OCA adhesive layer, significantly reducing the structural thickness. Generally, the thickness of a traditional GFF structure is about 1.15 mm, while this solution can reduce the thickness by 0.1-0.2 mm through stacking optimization.
[0055] In addition, by creating a grid trench in the insulating layer to fill the metal grid (receiving electrode layer 5), the electrical isolation between the receiving electrode layer 5 and the transmitting electrode layer 2 is ensured, and the metal grid can be quickly and accurately manufactured. At the same time, the insulating layer provides more comprehensive and reliable protection for the metal grid.
[0056] (2) Improved reliability and suppression of ion migration: In this design, the emitting electrode layer 2 is made of indium tin oxide, which has high oxidation resistance and thermal stability, and can effectively suppress the problem of metal ion migration under high temperature and high humidity conditions. The receiving electrode layer 5 uses a metal mesh. The metal mesh serves as the cathode (low potential layer), which is less affected by ion migration in the electric field, and its low sheet resistance can improve touch sensitivity.
[0057] (3) Cost reduction and process simplification: Eliminating one layer of PET substrate 1 and OCA adhesive directly reduces raw material costs. Traditional GFF requires the separate fabrication of two conductive films and multiple laminations, while this solution reduces the number of processes and shortens the production cycle through an integrated process (etching ITO layer → fabricating insulating trenches → filling metal mesh), while also avoiding yield losses caused by multi-layer lamination (such as white spots, misalignment, etc.).
[0058] In some embodiments, step S1 includes the following steps:
[0059] S11. Cut the indium tin oxide film into sheets of corresponding sizes according to the design dimensions of the capacitive touchscreen;
[0060] S12. Aging and shrinking of indium tin oxide film sheets.
[0061] The PET substrate 1 of the indium tin oxide film is prone to deformation (shrinkage rate of about 0.1%-0.3%) when the temperature and humidity change. In this embodiment, by performing an aging and shrinkage treatment in advance (such as standing in a constant temperature and humidity environment for 48 hours), the internal stress of the substrate 1 can be released, eliminating the risk of uncontrollable shrinkage in subsequent processes.
[0062] In some embodiments, step S2 includes the following steps:
[0063] S21. Screen-print conductive metal in the non-display area around the indium tin oxide film and cure it;
[0064] S22. Simultaneously, the indium tin oxide film and the conductive metal are etched to obtain the conductive lines that establish the connection and the emission electrode layer 2.
[0065] The conductive lines arranged around the emitting electrode layer 2 can be used as pins to establish a connection between the emitting electrode layer 2 and the touch chip.
[0066] In this embodiment, after screen printing conductive metal (such as silver paste or copper paste) on the non-display area of the indium tin oxide film and curing it, the ITO layer and conductive metal are simultaneously etched. This eliminates the steps of step-by-step etching and multiple mask protection in traditional processes, simplifying the process, improving efficiency, and reducing costs. Furthermore, after screen printing the conductive metal on the non-display area, simultaneous etching achieves a seamless connection between the conductive lines (such as the border silver lines) and the emitter electrode layer 2. This ensures a precise and reliable connection between the border conductive lines and the emitter electrode layer 2.
[0067] In step S22, preferably, a hydrochloric acid-based solution is used to simultaneously etch the conductive metal and indium tin oxide, while methylbenzotriazole is added to suppress over-etching of the substrate 1.
[0068] The conductive metal used for screen printing is preferably silver paste or copper paste, and the curing method is baking curing.
[0069] After step S22, the workpiece is washed with water to remove impurities and dust.
[0070] In some embodiments, the grid grooves are formed by an imprinting process during the step of fabricating the insulating layer 4.
[0071] In this embodiment, an imprinting process is used to directly imprint grid trenches onto an insulating material (such as UV-curable resin) using a physical mold. The trench width and depth can be precisely controlled to the ±1μm level (compared to approximately ±5μm error in traditional photolithography). This effectively ensures the orthogonal alignment accuracy (error < ±3μm) between the metal grid (receiving electrode layer 5) and the indium tin oxide layer (emitting electrode layer 2), avoiding crosstalk in touch signals. Furthermore, the sidewall steepness of the imprinted grid trenches can be >85°, effectively preventing lateral diffusion during metal filling (compared to approximately 60° sidewall angle in traditional etching processes), reducing the risk of short circuits.
[0072] In addition, the imprinting process does not require coating photoresist, exposure and development, and chemical etching. The groove structure is formed directly through the mold, which can save consumables such as photoresist (accounting for about 15% of the cost) and etching solution (such as hydrogen fluoride), reducing the cost of a single process by 20%-30%.
[0073] In some embodiments, step S2 further includes the following steps:
[0074] S23. A hardened layer 3 covering the emitting electrode layer 2 is formed on the top surface of the indium tin oxide film, and then the insulating isolation layer 4 is formed on the hardened layer 3.
[0075] The imprinting process requires applying pressure (usually 5-20 MPa) to the insulating layer material through a mold. This pressure will indirectly affect the underlying structure (i.e., the emitting electrode layer 2). In this solution, adding a hardener to the surface of the emitting electrode layer 2 can effectively disperse the imprinting pressure and avoid the problem of microcracks or peeling of the indium tin oxide layer due to local stress concentration.
[0076] Furthermore, when the insulating layer 4 (such as UV-curable resin) is directly coated onto the surface of indium tin oxide, insufficient adhesion may result due to differences in surface energy. The hardened layer 3, as an intermediate layer, can optimize the surface energy (such as the surface energy of SiO2, which is approximately 50 mN / m), effectively improving the adhesion of the insulating layer.
[0077] The hardener used in the hardening layer 3 can be, but is not limited to, silicon dioxide (SiO2), silicon nitride (SiNx), aluminum oxide (Al₂O₂), or silicone-based organic resin (such as...). After applying the hardener, a suitable method (such as UV curing or baking curing) is used to cure the coating or a nanocomposite coating (such as SiO2 nanoparticle dispersion resin).
[0078] Preferably, the thickness of the hardened layer 3 does not exceed 1 μm, such as 0.8 μm, 0.85 μm, 0.9 μm, 0.95 μm, or 1 μm.
[0079] When the thickness of the hardened layer 3 is controlled at 0.8-1 μm, the transmittance of inorganic materials (such as SiO2, SiNx) in the visible light band (380-780nm) can be maintained at >99%, and the transmittance of organic-inorganic hybrid materials (such as silicon-based resin) is >95%, with almost no additional loss in display brightness. Moreover, such a thickness can effectively disperse the local pressure in the imprinting process and prevent microcracks from forming in the ITO layer.
[0080] In some embodiments, step S3 includes the following steps:
[0081] S31. Apply UV-curable adhesive;
[0082] S32. Perform photocuring and imprinting processes to obtain the insulating isolation layer 4 with the grid grooves.
[0083] UV-curable adhesives (such as UV-curable resins) can achieve curing in seconds (typically 1-10 seconds) under ultraviolet light irradiation, significantly shortening the imprinting cycle. Traditional hot imprinting processes require heating to above the polymer's glass transition temperature (taking several minutes), while in this embodiment, a UV-curable adhesive is used as the material for the insulating layer 4 to complement the imprinting process. The UV-curable adhesive undergoes UV pre-curing + imprinting + secondary curing, reducing the total time by more than 60%. Furthermore, the low viscosity (typically <500 mPa·s) and high leveling properties (surface roughness Ra <0.1 μm) of the UV-curable adhesive allow for precise filling of micron-level grooves (e.g., 10-50 μm linewidth) in the imprinting mold, with a replication error of <±1 μm.
[0084] Preferably, the thickness of the photocurable adhesive is controlled between 15 and 20 μm. This thickness can ensure that there is a suitable distance between the emitting electrode layer 2 and the receiving electrode layer 5, avoiding the problems of increased load and low signal-to-noise ratio caused by the two being too close and having too large a capacitance.
[0085] In some embodiments, in step S32 above, the photocuring and imprinting processes are completed simultaneously in one process.
[0086] In other words, the same equipment includes a UV lamp and an impression roller. The UV lamp is located in front of the impression roller, and it moves synchronously with the roller as it presses against the surface, thus achieving simultaneous curing and impression processes (in fact, curing takes precedence over impression). For example, in a specific setup, the UV lamp is positioned in front of the impression roller. Before the roller contacts the UV-curable adhesive, the UV light pre-cures the adhesive (to a degree of curing of 50-70%), forming a semi-solid surface layer (approximately 1-2 μm thick). The roller can then easily imprint stable grooves onto this semi-cured surface layer. The roller and UV lamp are linked by a servo motor to ensure they move at the same linear speed (e.g., 0.5-2 m / min), preventing tearing or air bubbles in the adhesive layer due to speed differences.
[0087] In this embodiment, a single-process integration is adopted, which eliminates the step-by-step process of "coating → pre-curing → imprinting → secondary curing" in the traditional process, and shortens the single imprinting cycle by 60% (from 120 seconds to 50 seconds).
[0088] In some embodiments, step S32 above includes the following steps:
[0089] S321. First light curing stage: Low-intensity light is used to partially cure the colloid;
[0090] S322. Imprinted grooves: The grid grooves are formed by imprinting;
[0091] S323. Second light curing stage: High-intensity light is used to completely cure the colloid.
[0092] In this embodiment, the first photocuring stage (low-intensity semi-curing) uses low-intensity ultraviolet light (e.g., 30-50 mW / cm²) to locally crosslink the photocurable adhesive, forming a semi-solid layer on the adhesive surface (curing degree approximately 50-70%) while maintaining internal fluidity. This semi-cured layer fixes the adhesive's position, preventing excessive flow during imprinting that could cause pattern misalignment (alignment error < ±1 μm). The uncured area maintains a low viscosity (< 500 mPa·s), ensuring the adhesive fully fills the mold cavity during imprinting (aspect ratio > 5:1).
[0093] During the embossing groove formation, the embossing pressure is 5-20MPa and the mold moving speed is 0.5-2m / min, forming a grid groove with a width of 10-50μm and a depth of 5-15μm. The steepness of the groove sidewall is >85°, ensuring the orthogonal alignment accuracy (deviation <±3μm) between the subsequent metal grid (receiving electrode layer 5) and the ITO layer (emitting electrode layer 2).
[0094] The second stage of photocuring (high-intensity complete curing) uses high-intensity ultraviolet light (e.g., 100-150mW / cm²). 2 This process ensures complete cross-linking of the colloid (curing degree >98%), forming an insulating layer with high hardness (≥3H) and low dielectric constant (ε≈2.8-3.5). After complete curing, the peel strength is >5 N / cm, enhancing adhesion to the ITO layer. The dense structure blocks water and oxygen permeation (WVTR <10). -3 After aging at high temperature and humidity (85℃ / 85%RH), the resistivity change rate is <2%; by adjusting the refractive index (e.g., SiO2 transition layer n≈1.46), the interface reflectivity is reduced from 4% to <0.5%, and the transmittance is >95%.
[0095] Based on the above embodiments, the high-precision, high-reliability, and high-efficiency manufacturing of the insulating layer 4 is achieved through segmented curing, while ensuring the accuracy of the formed mesh grooves and improving the accuracy of the subsequent metal mesh production.
[0096] In some embodiments, step S4 includes the following steps:
[0097] S41. Use a scraper to fill the metal slurry into the grid trench;
[0098] S42. Solidify the metal slurry to form the receiving electrode layer 5.
[0099] In this embodiment, a metal slurry (such as nano-silver paste or copper paste) is applied and filled into pre-formed mesh grooves using a doctor blade. The doctor blade pressure is controlled at 0.1-0.5 MPa to avoid excessive compression that could cause slurry overflow or groove deformation. Preferably, a vacuum adsorption device (vacuum degree ≤10 Pa) is used to assist the slurry flow and eliminate residual air bubbles.
[0100] Curing methods include thermal curing and photocuring. Specifically, thermal curing involves a stepped temperature increase (e.g., 80℃→120℃→150℃, each stage lasting 10-30 minutes) to allow the solvent to evaporate and promote the sintering of metal particles. This is suitable for nano-silver pastes (conductivity increases by 30% after sintering). Photocuring involves irradiation with ultraviolet light (wavelength 365nm, intensity 100-200mW / cm2) for 10-60 seconds. This is suitable for copper pastes containing photosensitive resins, and the hardness after curing is ≥3H.
[0101] By employing a process that combines the application of metal slurry with curing, a metal mesh that is highly integrated with the mesh trenches can be obtained, ensuring both the reliability of the structure and the precision of the metal mesh.
[0102] Preferably, after the metal slurry is cured in step S42, the surface of the insulating layer 4 is wiped to remove any metal slurry residue.
[0103] In some embodiments, after fabricating the receiving electrode layer 5, the following steps are performed:
[0104] S5. Optical adhesive 6 is attached to the receiving electrode layer 5;
[0105] S6. Bond the flexible circuit board and bring out the internal circuitry;
[0106] S7. Functional test;
[0107] S8. Attach the protective panel 7 to the optical adhesive 6.
[0108] The optical adhesive 6 is preferably OCA, and its main function is to cover and protect the insulating isolation layer 4 with the receiving electrode layer 5, and to reliably bond the insulating isolation layer 4 to the protective panel 7 (generally glass).
[0109] By binding a flexible circuit board to bring out the internal circuitry, it is easy to establish a connection between the touch chip and the internal circuitry later through the flexible circuit board.
[0110] Functional testing typically includes electrical performance testing and environmental reliability testing, which can ensure product yield.
[0111] In some embodiments, after completing the functional test in step S7 and determining that the product is good, sealant is applied to the exposed area of the bonded metal wire.
[0112] In this embodiment, by applying sealant to protect the exposed metal wire area after functional testing, both oxidation protection and structural stability are improved.
[0113] On the other hand, this embodiment also provides a capacitive touch screen, which is manufactured according to the above-described method for manufacturing a capacitive touch screen.
[0114] Specifically, the capacitive touch screen of this embodiment includes at least the following layers stacked in sequence: a substrate 1, an emitting electrode layer 2, a hardening layer 3, an insulating layer 4, and a receiving electrode layer 5, wherein the emitting electrode layer 2 is an indium tin oxide mesh, and the receiving electrode layer 5 is a metal mesh.
[0115] Similarly, the capacitive touchscreen manufactured using the method described in this embodiment has the advantages of being thin, low-cost, reliable, and having a long lifespan.
[0116] In the description herein, it should be understood that the terms "upper," "lower," "left," "right," and other orientations or positional relationships are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used merely for descriptive distinction and have no special meaning.
[0117] In the description of this specification, references to terms such as "an embodiment," "example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.
[0118] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
[0119] The technical principles of this application have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of this application and should not be construed as limiting the scope of protection of this application in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of this application without inventive effort, and these embodiments will all fall within the scope of protection of this application.
Claims
1. A method for manufacturing a capacitive touchscreen, characterized in that, Including the following steps: Provide indium tin oxide film; An electrode pattern is etched onto the indium tin oxide film to form an emission electrode layer; An insulating layer with grid grooves is fabricated on the emitting electrode layer; A metal mesh is fabricated in the mesh trenches of the insulating layer to form a receiving electrode layer.
2. The method for manufacturing a capacitive touchscreen according to claim 1, characterized in that, Before etching to form the emitter electrode layer, conductive metal is screen-printed and cured in the non-display area around the indium tin oxide film; during etching, the indium tin oxide film and the conductive metal are etched simultaneously to obtain the conductive lines that establish the connection and the emitter electrode layer.
3. The method for manufacturing a capacitive touchscreen according to claim 1, characterized in that, In the step of making the insulating layer, the grid grooves are formed by an imprinting process.
4. The method for manufacturing a capacitive touchscreen according to claim 3, characterized in that, After fabricating the emitter electrode layer, a hardened layer covering the emitter electrode layer is formed on the top surface of the indium tin oxide film, and then the insulating layer is formed on the hardened layer.
5. The method for manufacturing a capacitive touchscreen according to claim 3, characterized in that, In the process of making the insulating layer, a light-curing adhesive is first applied, followed by light curing and imprinting to obtain the insulating layer with the grid grooves.
6. The method for manufacturing a capacitive touchscreen according to claim 5, characterized in that, In the process of making the insulating layer, the photocuring and imprinting processes are completed simultaneously in one step.
7. The method for manufacturing a capacitive touchscreen according to claim 6, characterized in that, The process of photocuring and imprinting includes two photocuring stages. In the first photocuring stage, low-intensity light is used to semi-cur the colloid, and then imprinting is used to form the grid grooves. In the second photocuring stage, high-intensity light is used to completely cure the colloid.
8. The method for manufacturing a capacitive touchscreen according to claim 1, characterized in that, The process of fabricating the receiving electrode layer includes the following steps: using a scraper to fill the mesh trench with molten metal and then curing the molten metal to form the receiving electrode layer.
9. The method for manufacturing a capacitive touchscreen according to claim 1, characterized in that, After completing the fabrication of the receiving electrode layer, the following steps are performed: Optical adhesive is bonded onto the receiving electrode layer; Bond the flexible circuit board and bring out the internal circuitry; Functional testing; The protective panel is attached to the optical adhesive.
10. A capacitive touchscreen, characterized in that, It is manufactured according to the method of manufacturing a capacitive touch screen as described in any one of claims 1-9.