A method for manufacturing a flexible transparent conductive film for complex environments

Abstract

The application discloses a manufacturing method of a flexible transparent conductive film facing complex environment, and the method comprises the following steps: firstly, a flexible silica gel mold with cavities is manufactured by using a turning mold process of a silica mold; then, initial functional materials are filled in the flexible silica gel mold; then, the flexible film filled with the initial functional materials is subjected to functionalization treatment to obtain consolidated functional materials; the flexible silica gel mold is repeatedly filled for multiple times; then, a protective layer metal is manufactured on the surface of the completed flexible conductive film; finally, the flexible conductive film is integrally packaged to obtain the flexible transparent conductive film facing the complex environment; the flexible transparent conductive film with stable performance can be manufactured by using the method, the flexible transparent conductive film can be applied to the complex environment field such as high and low temperature vibration, the method has strong inclusiveness for various materials, and the manufacturing method is simple and reliable.

Description

Technical Field

[0001] This invention belongs to the field of flexible transparent conductive film technology, and specifically relates to a method for manufacturing a flexible transparent conductive film for complex environments. Background Technology

[0002] Flexible transparent conductive films have been extensively studied due to their excellent optoelectronic properties and are widely used in mature fields such as touch screens, OLEDs, and solar cells. In recent years, with the development of the Internet of Things concept, the detection requirements of information flow such as sensing, detection, feedback, and processing in many high-end equipment, bionic robots, special processing manipulators, and smart factories have further expanded the emerging industrial applications of flexible transparent conductive films. Therefore, researching new processes for flexible transparent conductive films to make them more environmentally adaptable is an inevitable path for the development of flexible transparent conductive films.

[0003] Flexible transparent conductive films can be categorized based on the materials used in their fabrication, including conductive metal oxides, conductive polymers, carbon materials (such as carbon nanotubes and graphene), and metal nanomaterials (such as nanowires and nanoparticles). Metal oxides are typically manufactured using vapor deposition, conductive polymers generally use screen printing, carbon materials are typically manufactured using spin coating or vacuum filtration, and metal nanomaterials are generally manufactured using vacuum filtration-hot pressing transfer or spin coating processes. When applied to complex environments such as high and low temperatures, vibration, and impact, flexible transparent conductive films produced using these methods may exhibit drawbacks such as film detachment, decreased conductivity, decreased transparency, and unstable performance. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide a method for manufacturing a flexible transparent conductive film for complex environments. This method can achieve stable manufacturing of flexible transparent conductive films, which can be applied to complex environments such as high and low temperature vibration, and has strong compatibility with a variety of materials. The manufacturing method is simple and reliable.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A method for manufacturing a flexible transparent conductive film for complex environments includes the following steps:

[0007] 1) A flexible silicone mold with a concave cavity is manufactured using the silicone mold flipping process;

[0008] 2) Fill the flexible silicone mold manufactured in step 1) with the initial functional material 2;

[0009] 3) The flexible membrane filled with the initial functional material 2 in step 2) is functionalized to obtain the solidified functional material 3;

[0010] 4) Repeat steps 2)-3) to fill the flexible silicone mold 1 multiple times according to actual needs;

[0011] 5) A protective metal layer 4 is fabricated on the surface of the flexible conductive film filled in step 4);

[0012] 6) The flexible conductive film with protective metal layer 4 is encapsulated as a whole to obtain a flexible transparent conductive film for complex environments.

[0013] In step 1), the silicon mold is manufactured using a duplication molding process to create a flexible silicone mold, which requires the design of a cavity linewidth of less than 10 micrometers.

[0014] In step 2), the initial functional material 2 refers to a paste-based material with good conductivity, such as silver nanoparticles, silver ink, or copper ink.

[0015] In step 3), functionalization refers to the treatment of the external environment, such as temperature field, magnetic field, and electric field, based on the characteristics of the initial functional material 2, so that the slurry-based material becomes a conductive solidified functional material 3.

[0016] In step 4), the filling rate of the consolidation functional material 3 in the cavity is increased by filling multiple times to ensure the good conductivity of the conductive film.

[0017] In step 5), the protective layer metal 4 usually refers to a protective layer with strong chemical stability, such as gold, in order to protect the solidified functional material 3 from contact with the outside air and thus ensure good conductivity.

[0018] In step 5), the protective layer metal 4 is prepared by chemical deposition, electroplating and other methods.

[0019] The beneficial effects of this invention are as follows: This invention fills a flexible microstructure cavity with a functional material of micron-thickness, and then deposits a more stable metal protective layer (nanoscale) on the surface. The thick functional material ensures strong conductivity and resistance to external damage, while the thin metal protective layer protects the chemical stability of the filled functional material. Because this invention adopts this structure of filling the cavity with functional material and surface-stable metal protection, the manufactured transparent conductive film exhibits stronger stability and more reliable performance in complex environments.

[0020] The flexible transparent conductive film manufactured by this invention possesses strong chemical stability, enabling it to adapt to complex environments. The manufacturing process of this invention is simple and applicable to a variety of materials. It has a wide range of applications, particularly in complex environments such as high-temperature welding robots and specialized robotic arms. Attached Figure Description

[0021] Figure 1This is a top view schematic diagram of a flexible silicone mold with a grid pattern, as shown in the embodiment.

[0022] Figure 2 This is a schematic cross-sectional view of a flexible silicone mold with a grid pattern, as shown in the embodiment.

[0023] Figure 3 This is a schematic diagram of the initial state functional material being filled in for an example.

[0024] Figure 4 This is a schematic diagram of the functional material after functionalization in its initial state, as shown in the example.

[0025] Figure 5 This is a schematic diagram of the embodiment after multiple fillings of functional materials and functionalization treatment.

[0026] Figure 6 This is a schematic diagram illustrating the fabrication of a protective metal layer on the surface of a solidified functional material, as an example.

[0027] Figure 7 This is a schematic diagram of the transparent conductive film after surface encapsulation in an embodiment.

[0028] Figure 8 This is a schematic diagram illustrating the flexibility and light transmittance of the flexible transparent conductive film fabricated for this embodiment.

[0029] Figure 9 This is a scanning electron microscope image showing the initial state functional material being filled into the cavity during the fabrication of the transparent conductive film in an embodiment.

[0030] Figure 10 For comparison, the left side shows the resistance test of a regular flexible transparent conductive film (without a protective metal layer); the right side shows the resistance test of a flexible transparent conductive film (with a protective metal layer) manufactured in the example for complex environments. Detailed Implementation

[0031] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0032] A method for manufacturing a flexible transparent conductive film for complex environments includes the following steps:

[0033] 1) A flexible silicone mold with a concave cavity is manufactured using a silicone mold flipping process:

[0034] Flexible silicone was directly cast onto a silicon mold manufactured using MEMS etching technology. After vacuum degassing and drying, the silicone was obtained as shown in the image. Figure 1 The flexible silicone mold 1 shown in this step requires that the line width be as small as possible in order to ensure that the conductive film has good light transmittance. At the same time, the size of the functional material particles also needs to be considered so that they can be filled in. In this embodiment, the flexible silicone mold 1 has a 5μm mesh.

[0035] 2) Fill the flexible silicone mold manufactured in step 1) with initial functional material 2:

[0036] The cross-sectional view of the manufactured flexible silicone mold 1 is as follows Figure 2 As shown, its linewidth has a cavity, which is filled with a preliminary functional material 2. In this embodiment, the preliminary functional material 2 is a silver ink paste-based material. The schematic diagram after filling is shown below. Figure 3 As shown;

[0037] 3) Functionalize the flexible membrane filled with the initial functional material 2 in step 2):

[0038] A flexible silicone mold 1 filled with the initial functional material 2 was placed in a temperature field of 80°C to evaporate the solvent of the initial functional material 2. After half an hour, it was placed in a temperature field of 130°C, and the silver particles solidified to obtain solidified functional material 3. Solidified functional material 3 enhances the conductivity of the paste-based material. A schematic diagram of the functionalized treatment is shown below. Figure 4 As shown, the solidified functional material 3 exhibits morphological and volume shrinkage compared to the slurry-based material;

[0039] 4) Repeat steps 2)-3) to fill the flexible silicone mold 1 multiple times according to actual needs;

[0040] To increase the filling degree of the solidified functional material 3, the initial functional material 2 was repeatedly filled into the cavity of the flexible silicone mold 1, and then placed in a temperature field for functionalization treatment, so that the slurry-based material was functionalized into the solidified functional material 3. After multiple fillings, the flexible silicone mold 1 with a large filling rate was obtained, as shown in the figure. Figure 5 As shown;

[0041] 5) A protective metal layer 4 is fabricated on the surface of the flexible conductive film filled in step 4) to protect the previously filled solidified functional material 3;

[0042] After step 4), the flexible silicone mold 1 is coated with a protective metal layer. The protective metal layer is composed of elements with relatively stable chemical properties. In this embodiment, Au is chosen as the protective metal layer, mainly because conductive inks such as Ag or Cu are easy to fill. However, the biggest problem is that they are prone to oxidation, which seriously affects the conductivity of the solidified functional material 3. When facing complex environments, especially in working conditions with varying temperatures, humidity, and chemical atmospheres, the deterioration of conductivity will lead to performance weakening or complete failure. Under the action of Au, the conductivity and oxidation resistance of the solidified functional material 3 are improved. After the protective metal layer 4 is coated on the solidified functional material 3, as shown... Figure 6 As shown;

[0043] In this step, the protective layer metal 4 can be manufactured by various metal thin film deposition methods such as vapor deposition, sputtering, and electroplating. It is important to note that the previously filled solidified functional material 3 must be completely covered for the best effect.

[0044] 6) The flexible conductive film with protective metal layer 4 is encapsulated as a whole to obtain a flexible transparent conductive film for complex environments;

[0045] After step 5) is completed, silicone of the same material as the flexible silicone mold 1 is poured onto the flexible conductive film. After vacuum degassing, it is evenly and thinly coated onto the surface of the flexible silicone mold 1 using a spin coater. It is then placed in an oven or at room temperature to cure, resulting in a flexible transparent conductive film suitable for complex environments, such as... Figure 7 As shown.

[0046] Figure 8 This demonstrates that the flexible transparent conductive film manufactured in this embodiment possesses both flexibility and transparency. Figure 9 This is a scanning electron microscope image showing the functional material being filled into the cavity during the fabrication of a transparent conductive film. Figure 10 The performance of the manufactured flexible transparent conductive film for complex environments is compared with that of ordinary conductive films: the left side shows the resistance test of ordinary transparent conductive film (without protective metal layer 4); the right side shows the resistance test of transparent conductive film for complex environments manufactured in the example (with protective metal layer 4), which fully demonstrates that the transparent conductive film with protective metal layer has better conductivity.

Claims

1. A method for manufacturing a flexible transparent conductive film for complex environments, characterized in that, Includes the following steps: 1) A flexible silicone mold with a concave cavity is manufactured using the molding process of silicone mold (1). 2) Fill the flexible silicone mold manufactured in step 1) with the initial state functional material (2); The initial state functional material (2) refers to a paste-based material with good conductivity, such as silver nanoparticles, silver ink, or copper ink; 3) The flexible membrane filled with the initial functional material (2) in step 2) is functionalized to obtain the solidified functional material (3); The aforementioned functionalization treatment refers to the treatment of the external environment of temperature field, magnetic field and electric field based on the characteristics of the initial state functional material (2), so as to transform the slurry-based material into a conductive solidified functional material (3). 4) Repeat steps 2)-3) to fill the flexible silicone mold (1) multiple times according to actual needs; 5) A protective metal layer (4) is fabricated on the surface of the flexible conductive film filled in step 4). The protective layer metal (4) is a gold protective layer that protects the solidification functional material (3) from contact with the outside air; 6) The flexible conductive film with protective metal layer (4) is encapsulated as a whole to obtain a flexible transparent conductive film for complex environments.

2. The manufacturing method according to claim 1, characterized in that: In step 1), the silicon mold is manufactured using a duplication molding process to create a flexible silicone mold, which requires a cavity linewidth of less than 10 micrometers.

3. The manufacturing method according to claim 1, characterized in that: In step 4), the filling rate of the consolidation material (3) in the cavity is increased by filling it multiple times to ensure the good conductivity of the conductive film.

4. The manufacturing method according to claim 1, characterized in that: In step 5), the protective layer metal (4) is prepared by chemical deposition and electroplating.

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