Manufacturing method of transparent metal grid conductive film
Through the method of combining template method and transfer, transparent metal grid conductive materials are prepared, which solves the problems of complex processes, expensive raw materials and insufficient conductivity in the prior art, and achieves the combination of efficient conductivity and flexibility, which is suitable for a variety of electronic devices.
Patent Information
- Application Number
- CN202510179402.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-18
- Publication Date
- 2025-04-29
AI Technical Summary
The preparation process of existing transparent metal grid conductive materials is complex, the raw materials are expensive, and the conductivity is insufficient, making it difficult to meet the demand for efficient conductivity of electronic devices.
The method of combining template method with transfer is adopted to modify the substrate surface, prepare a solution containing metal nanowires, form a droplet array on the template, heat-forming, and transfer the metal grid frame to the target substrate through transfer, combine monomer polymerization or add adhesive layer to achieve close bonding between the metal grid and the substrate.
The uniform dispersion of metal nanowires is achieved and the continuous grid structure is formed, which significantly improves the conductive properties of the material, reduces contact resistance, improves the conductive efficiency, and gives the material a certain degree of flexibility. It is suitable for a variety of electronic devices.
Smart Images
Figure CN119905290A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of transparent conductive materials, and in particular to a method for manufacturing a transparent metal grid conductive film. Background Art
[0002] As a very important electronic component, transparent conductive materials are widely used in touch screens, heating films, electromagnetic shielding films, 5G transparent film antennas, etc. Commonly used transparent conductive materials include ITO, nanosilver, metal mesh, etc. Among them, metal mesh has attracted much attention due to its excellent performance.
[0003] Metal mesh is usually made of metal film through yellow light subtractive process. The one-piece molding process gives it excellent electrical properties and curling properties, but the process is relatively complicated. In recent years, with the development of additive method, metal mesh has been freed from the limitation of raw materials to a certain extent, but the process has not been completely simplified.
[0004] Based on the above background, the development of new transparent metal conductive films will further promote the development of transparent conductive materials and is of great significance. Summary of the invention
[0005] The object of the present invention is to provide a method for manufacturing a transparent metal grid conductive film to solve the problems raised in the above background technology.
[0006] To achieve the above object, the present invention provides the following technical solution: a method for manufacturing a transparent metal grid conductive film, comprising the following steps: S1: selection and surface modification of a substrate, controlling the surface energy of the material, and facilitating the smooth progress of a subsequent template method;
[0007] S2: preparing a solution component containing metal nanowires, adding a certain amount of surfactant to the metal nanowires, and preparing an aqueous solution;
[0008] S3: Using the template method to form a droplet array on the template surface, the size of the metal grid mesh can be preliminarily determined by controlling the droplet size;
[0009] S4: The solution is heated and volatilized, and the metal nanowires are dried and formed on the template to obtain a metal grid frame;
[0010] S5: Transfer of the metal mesh frame, transferring the metal mesh frame to the target substrate by transfer, and combining the metal mesh with the substrate by monomer polymerization or adding an adhesive layer, thereby obtaining a metal mesh material.
[0011] Preferably, the contact angle of the substrate with a water droplet is in the range of 20-70°.
[0012] Preferably, if the contact angle of the substrate is not within the above range, it can be achieved through surface modification. Hydrophilic modification can be achieved by plasma, and hydrophobic modification can be achieved by surface modification using silane or the like.
[0013] Preferably, the content of the metal nanowires is 0.1%-10%.
[0014] Preferably, the content of the surfactant is 0.01%-0.1%.
[0015] Preferably, the droplet size is 1-10 nL, the droplet falling height is 1-2 CM, and the droplet falls vertically.
[0016] Preferably, the heating temperature is controlled at 50-90°C.
[0017] Preferably, the inert and reducing gas flows are used to continuously remove water vapor and prevent the metal nanowires from being oxidized.
[0018] Preferably, the transparency of the substrate is above 90%, and the side of the substrate corresponding to the liquid and the side of the substrate corresponding to the outside are treated differently.
[0019] Preferably, the substrate is provided with a groove corresponding to the size of the liquid and a groove corresponding to the liquid contact position.
[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: by combining the template method with transfer printing, the preparation of metal nanowires into concave or convex transparent conductive metal grid materials is realized, and the product defects of the existing metal grid raw materials, such as large technical bottlenecks, high prices, and complex process technology, are solved. The metal nanowires are evenly dispersed in the droplets, and after drying, they overlap each other to form a continuous grid structure, which can construct a stable conductive path, and electrons can be efficiently transmitted in the grid, thereby significantly improving the conductive properties of the material, so that it can be better applied to electronic devices and other fields that require conductive properties. Compared with disorderly stacked metal nanowires, the contact between nanowires in the grid structure is tighter and more orderly, reducing the contact resistance caused by poor contact, further improving the overall conductive efficiency, and reducing energy loss. The metal grid inherits a certain flexibility of the metal nanowires. Compared with traditional metal films or bulk metals, it is less likely to break or damage when subjected to external forces, and can better adapt to different stress environments. For example, it can still maintain good electrical properties under deformation conditions such as bending and stretching, and is suitable for wearable devices, flexible electronic devices and other scenes with high flexibility requirements. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 This is a schematic diagram of the morphology of a droplet containing nanowires according to the present invention.
[0022] Figure 2This is a schematic diagram of the shape of the nanowire ring metal grid of the present invention.
[0023] Figure 3 This is a schematic diagram of the transfer of the transparent conductive metal grid of the present invention. DETAILED DESCRIPTION
[0024] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0025] See also Figures 1 to 3 The present invention provides a technical solution: a method for manufacturing a transparent metal mesh conductive film, comprising the following steps, S1: selection and surface modification of a substrate, controlling the surface energy of the material, facilitating the smooth progress of the subsequent template method, selecting different substrates according to different preparation needs, and achieving different production needs, surface modification refers to changing the chemical composition, organizational structure or morphology of the material surface by physical, chemical and other methods, thereby giving the material surface new properties, and specific change methods include ion implantation, laser surface treatment, physical vapor deposition, chemical plating and chemical vapor deposition, etc., to ensure that when the liquid drips on the substrate, it can form droplets with better shapes, thereby ensuring the subsequent formation effect of the metal mesh;
[0026] S2: preparing a solution component containing metal nanowires, adding a certain amount of surfactant to the metal nanowires, and preparing an aqueous solution. The addition of the surfactant can prevent the metal nanowires from agglomerating, and on the other hand, can make the nanowires gather at the gas-liquid-solid interface and achieve drying and forming at the interface;
[0027] S3: Use the template method to form a droplet array on the template surface. By controlling the droplet size, the size of the metal mesh can be preliminarily determined. The size of the droplets corresponds to the size of the metal mesh, and there are contact parts between the liquids, ensuring that the metal mesh is formed instead of metal rings.
[0028] S4: The solution is heated and volatilized, and the metal nanowires are dried and formed on the template to obtain a metal grid frame. During the heating process, the solution will form ring-shaped metals, thereby ensuring the formation of metal rings, and multiple metal rings form a metal grid;
[0029] S5: Transfer of metal mesh frame, transferring the metal mesh frame to the target substrate by transfer, and combining the metal mesh with the substrate by monomer polymerization or adding an adhesive layer, thereby obtaining a metal mesh material. Transfer in the printing industry mainly refers to the process of transferring the pattern, text and other content pre-printed on a certain medium to the surface of another object by means of certain pressure and adhesive, transferring the metal mesh from the template to the target substrate, and reinforcing it by monomer polymerization or adding an adhesive layer;
[0030] The contact angle of the water drop on the substrate ranges from 20-70°, which ensures the forming effect of the falling water drop and prevents the generation of irregular water droplets, thereby ensuring the forming effect of the metal grid after the water droplets are evaporated.
[0031] If the contact angle of the substrate is not within the above range, it can be achieved through surface modification. Hydrophilic modification can be achieved through plasma, and hydrophobic modification can be achieved by using silane or the like to modify the surface, thereby changing the contact effect between the substrate and the water droplets. Through the surface tension of the water droplets, the solution containing the metal nanowires is dripped onto the surface of the substrate to form droplets.
[0032] The content of metal nanowires is 0.1%-10%. By controlling the content of metal nanowires, the thickness of the metal grid is controlled, thereby achieving the production of metal grids with different thicknesses.
[0033] The surfactant content is 0.01%-0.1%. According to the tension of different substrates, the amount of surfactant added is adjusted to meet different usage requirements.
[0034] The droplet size is 1-10nL. The size of the metal grid after the droplet is formed is controlled by controlling the droplet size. The droplet height is 1-2CM, and the droplet is dripped vertically. Dropping the droplets at a lower height prevents the droplets from falling on the substrate, causing the droplets to be subjected to too much impact force and causing the droplets to scatter. At the same time, the vertical dripping design is also better for controlling the droplet falling trajectory.
[0035] The heating temperature is controlled at 50-90°C. By controlling the temperature, the evaporation rate of the droplets is controlled to ensure the molding effect.
[0036] The water vapor is continuously removed by an inert gas flow (such as nitrogen, argon, etc.) and a reducing gas flow (such as hydrogen), while preventing the metal nanowires from being oxidized.
[0037] The transparency of the substrate is more than 90%, which is convenient for observing the forming effect of the metal nanowires and ensuring the transparency of the finished product. In order to make a transparent metal grid conductive film, the side of the substrate corresponding to the liquid and the side of the substrate corresponding to the outside are treated differently. The surface energy of the inner side of the substrate needs to be controlled to ensure that the droplets form a ring after drying, while the outer side of the substrate needs certain protection capabilities, such as corrosion resistance, friction resistance, etc., to ensure that the substrate is not damaged.
[0038] Grooves corresponding to the size of the liquid and the contact positions of the liquid are provided on the substrate to guide the dripping of the liquid and the connection positions of the droplets, thereby ensuring the effect of the droplets after molding.
[0039] Working principle:
[0040] The selection and surface modification of the substrate, control of the surface energy of the material, and the convenience of the subsequent template method are to prepare a solution component containing metal nanowires, add a certain amount of surfactant to the metal nanowires, and prepare an aqueous solution, use the template method to form a droplet array on the template surface, and by controlling the droplet size, the size of the metal grid mesh can be preliminarily determined. The solution is heated and volatilized, and the metal nanowires are dried and formed on the template to obtain a metal grid frame. The metal grid frame is transferred to the target substrate by transfer, and the metal grid is combined with the substrate by monomer polymerization or adding an adhesive layer to obtain a metal grid material.
[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A method for manufacturing a transparent metal grid conductive film, characterized in that: The following steps are involved: S1: Selection and surface modification of substrates to control the surface energy of materials and facilitate the subsequent template method; S2: preparing a solution component containing metal nanowires, adding a certain amount of surfactant to the metal nanowires, and preparing an aqueous solution; S3: Using the template method to form a droplet array on the template surface, the size of the metal grid mesh can be preliminarily determined by controlling the droplet size; S4: The solution is heated and volatilized, and the metal nanowires are dried and formed on the template to obtain a metal grid frame; S5: Transfer of the metal mesh frame, transferring the metal mesh frame to the target substrate by transfer, and combining the metal mesh with the substrate by monomer polymerization or adding an adhesive layer, thereby obtaining a metal mesh material.
2. The method for manufacturing a transparent metal grid conductive film according to claim 1, characterized in that: The contact angle of the substrate with a water droplet is in the range of 20-70°.
3. The method for manufacturing a transparent metal grid conductive film according to claim 2, characterized in that: If the contact angle of the substrate is not within the above range, it can be achieved through surface modification. Hydrophilic modification can be achieved through plasma, and hydrophobic modification can be achieved through surface modification using silane, etc.
4. The method for manufacturing a transparent metal grid conductive film according to claim 3, characterized in that: The content of the metal nanowires is 0.1%-10%.
5. The method for manufacturing a transparent metal grid conductive film according to claim 4, characterized in that: The content of the surfactant is 0.01%-0.1%.
6. The method for manufacturing a transparent metal grid conductive film according to claim 5, characterized in that: The droplet size is 1-10 nL, the droplet falling height is 1-2 CM, and the droplet falls vertically.
7. The method for manufacturing a transparent metal grid conductive film according to claim 6, characterized in that: The heating temperature is controlled at 50-90°C.
8. The method for manufacturing a transparent metal grid conductive film according to claim 7, characterized in that: The inert and reducing gas flows are used to continuously remove water vapor and prevent the metal nanowires from being oxidized.
9. The method for manufacturing a transparent metal grid conductive film according to claim 8, characterized in that: The transparency of the substrate is above 90%, and the side of the substrate corresponding to the liquid and the side of the substrate corresponding to the outside are treated differently.
10. The method for manufacturing a transparent metal grid conductive film according to claim 9, characterized in that: The template is provided with a groove corresponding to the size of the liquid and a groove corresponding to the contact position of the liquid, and the template and the substrate are made of the same material.