Method and device for preparing metal nanowire film assisted by bladeless fan

Abstract

The present application discloses a method and device for preparing a metal nanowire film assisted by a bladeless fan, wherein a compressed air spray gun, an axial flow fan and a bladeless fan are provided, wherein the bladeless fan and the axial flow fan are sequentially located below the output end of the compressed air spray gun, the axial flow fan generates an upward spiral airflow in the space above the axial flow fan, and the bladeless fan generates a downward airflow in the space above the axial flow fan, and the middle part of the axial flow fan is a rotating platform; the method and device for preparing a metal nanowire film assisted by a bladeless fan provided by the present invention can control the uniform distribution of the conductive film, and the uniform airflow generated by the bladeless fan has little interference with the operation of the axial flow fan, and combined with the high-speed rotating coating substrate, uniform coating and uniform arrangement can be achieved, ensuring the uniformity and excellent conductivity of the conductive film; the optimized production process is simple to operate, and it is easy to achieve efficient production of large-area uniform conductive films.

Description

Technical Field

[0001] The present invention relates to the field of film coating technology, and in particular to a method and device for preparing a metal nanowire film assisted by a bladeless fan. Background Art

[0002] Conductive films made of metal nanowires (such as silver) show significant application potential in the field of conductive films due to their excellent conductivity, transparency, and flexibility. Compared to traditional indium tin oxide transparent conductive films, silver nanowire conductive films not only offer lower resistance and higher transmittance, but also hold great potential for application in flexible electronic devices. However, achieving high uniformity over large areas of silver nanowire conductive films has been a major challenge for both research and industry. This paper proposes a method and apparatus for producing uniform silver nanowire conductive films using a bladeless fan to address this challenge.

[0003] Taking the preparation of silver nanowire conductive films as an example, the current production process suffers from poor uniformity in the distribution of silver nanowires. Traditional spraying and spin coating techniques, due to the uneven distribution of silver nanowires on the transparent substrate and the complex mass and heat transfer processes during the annealing process, lead to the "coffee ring" phenomenon of the silver nanowires, that is, the "soft agglomeration" of the silver nanowires, resulting in uneven square resistance of the film. Furthermore, the uneven electrical properties can cause electromigration and uneven distribution of electro-Joule heating, which can easily lead to localized melting of the silver nanowires, that is, electrothermal failure of the silver nanowires in the nanowire network, and ultimately failure of the silver nanowire conductive film. These problems have become the main bottlenecks restricting the application of silver nanowire conductive films in flexible electronic devices.

[0004] The traditional spin coating method is difficult to prepare large-area thin films, while the silver nanowire conductive films prepared by the traditional spray coating method have poor uniformity. The reason for the poor uniformity of the traditional spray coating method is that the unstable airflow leads to uneven distribution of the silver nanowire droplets sprayed on the coated substrate. In addition, the traditional spray coating method has problems such as poor controllability, low efficiency and high cost in the preparation process. Specifically, parameters such as air pressure, wind speed, and spraying distance are difficult to control accurately, resulting in poor process repeatability, poor film quality, high scrap rate and high cost. At the same time, the traditional spray coating method also has material compatibility issues in the preparation process, because when used on different coated substrate materials, it is often necessary to adjust the process parameters in a targeted manner, making it difficult to achieve a universal preparation process. Summary of the Invention

[0005] The main purpose of the present invention is to provide a bladeless fan-assisted metal nanowire film preparation method and device, aiming to solve the problem that the traditional spin coating method is difficult to prepare large-area films and the conductive film has poor uniformity.

[0006] To achieve the above objectives, the present invention provides a method for preparing a metal nanowire film assisted by a bladeless fan, comprising:

[0007] S1. Provide a compressed air spray gun, an axial flow fan, and a bladeless fan, wherein the bladeless fan and the axial flow fan are sequentially located below an output end of the compressed air spray gun, the axial flow fan generates an upward spiral airflow in a space above the axial flow fan, and the bladeless fan generates a downward airflow in a space above the axial flow fan, and the middle portion of the axial flow fan is a rotating platform;

[0008] S2. Setting the output end of the compressed air spray gun to correspond to the bladeless fan;

[0009] S3, preparing a linear material dispersion and transferring it to a compressed air spray gun;

[0010] S4. Installing the film-coated substrate on the rotating platform, with the output end of the compressed air spray gun and the bladeless fan forming a vertical distance of 0.5-1.5 cm, and the film-coated substrate and the bladeless fan forming a vertical distance of 3-7 cm;

[0011] S5. Starting the compressed air spray gun, the axial flow fan, and the bladeless fan to coat the surface of the high-speed rotating film-coated substrate to form a wet film, wherein the rotation speed of the rotating platform is 2500 to 3500 rpm, the air inlet speed of the bladeless fan is set to 3 to 4 m / s, and the operating pressure of the compressed air spray gun is 0.5 to 2.0 MPa;

[0012] S6. Stop the compressed air spray gun, the axial flow fan, and the bladeless fan, remove the film-coated substrate, and perform heat treatment to form a conductive film.

[0013] Furthermore, the step S5 includes:

[0014] The wind speed below the axial flow fan and the wind speed above the bladeless fan are detected.

[0015] Furthermore, the step S5 includes:

[0016] S5.1. Adjust the working intensity of the axial flow fan and the bladeless fan so that the ratio of the wind speed below the axial flow fan to the wind speed above the bladeless fan is between 1:1.2 and 1:1.5.

[0017] Furthermore, the step S5.1 includes:

[0018] S5.2. Adjust the working intensity of the compressed air spray gun according to the wind speed above the bladeless fan.

[0019] The present invention also provides a device for use in the above-mentioned bladeless fan-assisted metal nanowire film preparation method, comprising:

[0020] Fixed bracket;

[0021] A compressed air spray gun is arranged at the upper part of the fixed bracket in the height direction;

[0022] a bladeless fan, correspondingly disposed below the output end of the compressed air spray gun, the bladeless fan generating a downward airflow;

[0023] An axial flow fan is arranged below the bladeless fan, and the axial flow fan generates an upward spiral airflow. The middle part of the axial flow fan is a rotating platform, and the upper part of the rotating platform is used for installing an external coating substrate.

[0024] Furthermore, the axial flow fan includes a rotatably arranged blade assembly, the middle portion of the blade assembly is perforated, and a support structure is provided corresponding to the rotating platform, the support structure including:

[0025] A lifting platform corresponding to the perforation arrangement;

[0026] A plane bearing is provided on the top of the lifting platform, and the rotating platform can be detachably provided on the upper surface of the plane bearing;

[0027] When the lifting platform rises and passes through the through-hole, the plane bearing and the fan blade assembly clamp the rotating platform; when the lifting platform descends to the through-hole, the rotating platform descends along with it.

[0028] Furthermore, a rotation speed measuring unit is provided corresponding to the rotating platform, a first wind speed sensor for testing vertical wind speed is provided corresponding to the space above the bladeless fan, and a second wind speed sensor for testing vertical wind speed is provided corresponding to the space below the axial flow fan.

[0029] Furthermore, a third wind speed sensor for testing the circumferential wind speed is provided in the space above the axial flow fan.

[0030] Furthermore, a droplet collecting device is provided below the axial flow fan.

[0031] Furthermore, a protective tube is provided between the axial flow fan and the bladeless fan.

[0032] The present invention provides a bladeless fan-assisted metal nanowire film preparation method and device, in which the uniform distribution of the conductive film can be controlled. The uniform airflow generated by the bladeless fan has little interference with the operation of the axial fan. Combined with the high-speed rotating coating substrate, uniform coating and uniform arrangement can be achieved, ensuring the uniformity and excellent conductivity of the conductive film; the optimized production process, the bladeless fan-assisted preparation device has a simple design and easy operation, and can be integrated with existing production lines to achieve efficient production of large-area uniform conductive films; it is suitable for large-area preparation, and by precisely controlling the wind speed and the rotation speed of the coating substrate, the present invention can prepare uniform conductive films on large-area coating substrates, and is suitable for industrial large-scale production.

[0033] The specific beneficial effects are as follows:

[0034] First, the uniform distribution of the conductive film can be controlled: the uniform airflow generated by the bladeless fan has little interference with the operation of the axial flow fan. Combined with the high-speed rotating coating substrate, uniform coating and uniform arrangement can be achieved, ensuring the uniformity and excellent conductivity of the conductive film.

[0035] Second, optimized production process: The bladeless fan-assisted preparation device is simple in design and easy to operate. It can be integrated with existing production lines to achieve efficient production of large-area uniform conductive films.

[0036] Third, it is suitable for large-area preparation: by precisely controlling the wind speed and the rotation speed of the coating substrate, the present invention can prepare a uniform conductive film on a large-area coating substrate, which is suitable for industrial large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a 5000x scanning electron microscope image of the conductive film in the bladeless fan-assisted metal nanowire film preparation method of the first embodiment of the present invention;

[0038] Figure 2 This is a diagram showing the sheet resistance distribution of the conductive film in the method for preparing a metal nanowire film assisted by a bladeless fan in the first embodiment of the present invention;

[0039] Figure 3 This is a diagram showing the sheet resistance distribution of the conductive film in the method for preparing a metal nanowire film assisted by a bladeless fan according to the second embodiment of the present invention;

[0040] Figure 4 This is a diagram showing the sheet resistance distribution of a conductive film in a method for preparing a metal nanowire film assisted by a bladeless fan according to a third embodiment of the present invention;

[0041] Figure 5 1 is a schematic diagram of a nanowire film preparation apparatus assisted by a bladeless fan according to a fourth embodiment of the present invention;

[0042] Figure 6Schematic diagram of a bladeless fan-assisted nanowire film preparation apparatus according to a fifth embodiment of the present invention (the rotating platform is at the lower left);

[0043] Figure 7 yes Figure 6 Local magnification of

[0044] Figure 8 1 is a schematic diagram of a bladeless fan-assisted nanowire film preparation apparatus according to a fifth embodiment of the present invention (the rotating platform is in the upper position);

[0045] Figure 9 This is a 5000x scanning electron microscope image of the conductive film of Comparative Example 1 of the present invention;

[0046] Figure 10 This is the square resistance distribution diagram of the conductive film in comparative example 1 of the present invention.

[0047] Figure markings: 010-filmed substrate, 100-compressed air spray gun, 200-axial flow fan, 210-rotating platform, 220-blade assembly, 221-perforation, 300-bladeless fan, 010-filmed substrate, 400-fixed bracket, 500-lifting platform, 600-plane bearing, 700-first wind speed sensor, 800-second wind speed sensor, 900-third wind speed sensor. DETAILED DESCRIPTION

[0048] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0049] Those skilled in the art will appreciate that, unless expressly stated otherwise, the singular forms “a”, “an”, “said”, “above” and “the” used herein may also include plural forms. It should be further understood that the term “comprising” used in the specification of the present invention refers to the presence of the described features, integers, steps, operations, elements, units, modules and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, units, modules, components and / or groups thereof. It should be understood that when we refer to an element as being “connected” or “coupled” to another element, it may be directly connected or coupled to the other element, or there may be intermediate elements. In addition, “connected” or “coupled” as used herein may include wireless connection or wireless coupling. The term “and / or” used herein includes all or any unit and all combinations of one or more associated listed items.

[0050] Those skilled in the art will understand that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art in the art to which this invention belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with their meanings in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless specifically defined as herein. Example 1

[0051] A method for preparing a metal nanowire film assisted by a bladeless fan, comprising:

[0052] In step S1, a compressed air spray gun 100, an axial flow fan 200 and a bladeless fan 300 are provided. The bladeless fan 300 and the axial flow fan 200 are sequentially located below the output end of the compressed air spray gun 100. The output end of the compressed air spray gun and the bladeless fan are vertically spaced 0.5 cm apart. The axial flow fan 200 generates an upward spiral airflow in the space above the axial flow fan 200. The bladeless fan 300 generates a downward airflow in the space above the axial flow fan 200, and a rotating platform 210 is provided in the middle of the axial flow fan 200. The rotating platform 210 is a part of the axial flow fan 200 or forms a detachable fit with the axial flow fan 200. The bladeless fan 300 generates a stable and uniform vertical downward airflow. During the spraying process, the droplets ejected from the compressed air spray gun 100 can be evenly distributed in the space above the axial flow fan 200. The axial flow fan 200 rotates to generate and generate an upward airflow. The wind speed measurement system is used to monitor the wind speed of the bladeless fan 300 in real time and adjust the wind speed to ensure the stability and appropriate wind speed of the airflow. In the plane direction, the operating range of the bladeless fan 300 covers the operating range of the axial flow fan 200.

[0053] In step S2, the output end of the compressed air spray gun 100 is set to correspond to the bladeless fan 300. The area of ​​the film substrate 010 is a PET sheet of 20mm×20mm. The steps for cleaning the film substrate 010 are as follows: put the film substrate 010 into a beaker, add an appropriate amount of detergent, perform ultrasonic oscillation for 15 minutes, and then wash it with a large amount of pure water. Add sufficient deionized water and use an ultrasonic cleaner to shake and clean it twice, each time for 15 minutes. Subsequently, pour out the deionized water, add a small amount of dimethyl acetone, and perform two 15-minute ultrasonic oscillations to remove residual organic matter. Finally, add an appropriate amount of anhydrous ethanol and perform two 20-minute ultrasonic cleanings. After cleaning, the clean film substrate 010 is re-sealed in anhydrous ethanol for standby use. Drying and surface modification of the film substrate 010: Take the film substrate 010 out of the anhydrous ethanol and dry it. The dried coated substrate 010 was treated with a plasma surface treatment machine at normal pressure for 20 seconds, and then treated with a 185nm ultraviolet ozone lamp for 30 minutes to improve the adhesion of the silver nanowires on the surface.

[0054] In step S3, a silver nanomaterial dispersion is prepared as a linear material dispersion. Preparation and cleaning of the silver nanomaterial: Purchase silver nanowires with a length of approximately 20 μm, a diameter of approximately 30 nm, and a purity >99 wt%. Mix the silver nanowires at a concentration of 10 mg / ml with 99% pure isopropyl alcohol at a volume ratio of 1:2. Transfer the linear material dispersion to a compressed air spray gun 100. In other implementations, the linear material dispersion can be prepared in various ways, using a suitable dispersion medium to form a dispersion of a suitable concentration.

[0055] In step S4, the film substrate 010 is mounted on the rotating platform 210. The film substrate 010 can be secured to the rotating platform 210 in various ways, including snap-fitting, buckling, or clamping. In other implementations, the film substrate 010 can be made of metal or an inorganic non-metallic material. The distance between the film substrate 010 and the bladeless fan 300 is 3 cm.

[0056] In step S5, the compressed air spray gun, the axial flow fan, and the bladeless fan are activated to form a wet film on the surface of the high-speed rotating film-coated substrate. The rotating platform rotates at 2500 rpm, the bladeless fan's air inlet speed is set at 3 m / s, and the compressed air spray gun operates at a pressure of 0.5 MPa. Droplets discharged from the output end of the compressed air spray gun 100 enter the working space of the bladeless fan 300. The droplets disperse and deposit on the rotating surface of the film-coated substrate 010, forming a wet film with a uniform distribution of silver nanowires. The coating time is 10-15 seconds. During the process, the wind speed below the axial flow fan 200 and above the bladeless fan 300 are measured. Although the wind speed above the axial flow fan 200 (i.e., below the bladeless fan 300) is the operating wind speed and is crucial for the film forming process, the wind field at this location is relatively turbulent, making wind speed measurement difficult and prone to errors. The wind speed below the axial fan 200 and the wind speed above the bladeless fan 300 are used as references to reflect the stability of the atomization process. The operating intensities of the axial fan 200 and the bladeless fan 300 are adjusted so that the ratio of the wind speed below the axial fan 200 to the wind speed above the bladeless fan 300 is 1:1.2. The operating intensities of the axial fan 200 and the bladeless fan 300 are matched so that the wind speed coordination falls within the set range. The wind field above the axial fan 200 is more suitable for droplet dispersion, providing the optimal combined web speed required for producing a uniform thin film. During implementation, the operating intensity of the compressed air spray gun 100 is adjusted (by fine-tuning the compressed air spray gun's operating pressure) based on the wind speed above the bladeless fan 300. The operating intensity of the bladeless fan 300 has already been adjusted based on the operating intensity of the axial fan 200. Therefore, the operating intensities of the bladeless fan 300 and the compressed air spray gun 100 are matched by adjusting the operating intensity of the compressed air spray gun 100. The working intensity adjustment of the compressed air spray gun 100 can adjust the spraying speed of the linear material dispersion, and finally obtain the optimal spraying speed required for the linear material dispersion to be evenly distributed in the space above the bottom of the coated substrate 010.

[0057] In step S6, the compressed air spray gun 100, axial flow fan 200, and bladeless fan 300 are stopped, and the film-coated substrate 010 is removed and heat-treated to form a conductive film. The prepared wet film is placed in an oven for a heat-insulating annealing treatment at 60°C for 40 minutes to remove the solvent and obtain a large, uniform silver nanowire conductive film. In other implementations, the heat treatment method is adjusted based on factors such as the type of linear material and the type of dispersion medium.

[0058] After testing, the transmittance of the prepared PET coated substrate 010 silver nanowire conductive film is 91%, and the square resistance is 10Ω / sq. The square resistance thermal diagram is shown as follows: Figure 2 As shown, the surface morphology is uniform, and its non-uniformity is 1.58%. Its SEM characterization is shown in Figure 1 shown. Example 2

[0059] Based on Example 1, the coating substrate 010 was replaced with glass; the wind speed of the bladeless fan 300 was set to 4.0 m / s; the output end of the compressed air spray gun was vertically 1.5 cm away from the bladeless fan; the coating substrate was vertically 7 cm away from the bladeless fan; the rotation speed of the rotating platform was 3500 rpm; the air inlet speed of the bladeless fan was set to 4 m / s; the operating pressure of the compressed air spray gun was 2.0 MPa; and the ratio of the wind speed below the axial flow fan to the wind speed above the bladeless fan was between 1:1.5. The above steps were repeated to prepare a wet film.

[0060] The prepared wet film was placed in an oven for heat preservation annealing treatment. The heat preservation temperature was set at 100°C and the heat preservation time was set for 25 minutes.

[0061] After testing, the prepared glass-coated substrate 010 silver nanowire conductive film has a transmittance of 95%, a square resistance of 8Ω / sq, a uniform surface morphology, and a non-uniformity of 1.83%. The square resistance thermal diagram is shown in the figure. Figure 3 shown. Example 3

[0062] On the basis of Example 1, the film-coating substrate 010 is replaced with ceramic, and the above steps are repeated to prepare a wet film.

[0063] The prepared wet film was placed in an oven for heat preservation annealing treatment. The heat preservation temperature was set at 100°C and the heat preservation time was set at 20 minutes.

[0064] After testing, the square resistance of the prepared ceramic coated substrate 010 silver nanowire conductive film is 6Ω / sq, the surface morphology is uniform, and the non-uniformity is 3.75%. The square resistance thermal diagram is shown in the figure. Figure 4 shown.

[0065] As demonstrated in Examples 1-3, the uniform silver nanowire conductive film prepared using the technical solutions of the present invention not only achieves a uniform distribution of nanowires on the film-coated substrate 010, but also achieves high production efficiency. The uniform silver nanowire film prepared by the present invention exhibits high light transmittance, excellent conductivity, and compatibility with other film-coated substrates 010 and metal nanowire materials. Example 4

[0066] On the basis of Example 1, the coating substrate 010 was replaced with glass, and the linear material dispersion was replaced with a copper nanowire dispersion with parameters of about 20 μm in length, about 30 nm in diameter, and a purity >99 wt %. The above steps were repeated to prepare a wet film.

[0067] The prepared wet film was placed in an oven for heat preservation annealing treatment. The heat preservation temperature was set at 100°C and the heat preservation time was set at 25 minutes.

[0068] After testing, the prepared glass-coated substrate 010 copper nanowire conductive film has a transmittance of 94%, a square resistance of 9Ω / sq, and a uniform surface morphology.

[0069] Comparative Example 1

[0070] The spin coating method is used to prepare a silver nanowire transparent conductive film. The method specifically includes the following steps:

[0071] Preparation and cleaning of silver nanomaterials: Purchase silver nanowires with parameters of about 20μm in length, about 30nm in diameter, and purity >99wt%. The coating substrate 010 is a sodium glass sheet with an area of ​​20mm×20mm. The steps for cleaning the coating substrate 010 are as follows: Place the coating substrate 010 in a beaker, add an appropriate amount of detergent, perform ultrasonic vibration for 15 minutes, and then wash with a large amount of pure water. Add sufficient deionized water and shake and clean it twice in an ultrasonic cleaner for 15 minutes each. Subsequently, pour out the deionized water, add a small amount of dimethyl acetone, and perform two 15-minute ultrasonic vibrations to remove residual organic matter. Finally, add an appropriate amount of anhydrous ethanol and perform two 20-minute ultrasonic cleanings. After cleaning, reseal the clean coating substrate 010 in anhydrous ethanol for later use.

[0072] Drying and Surface Modification of the Filmed Substrate 010: The filmed substrate 010 was removed from the anhydrous ethanol and dried. The dried filmed substrate 010 was then treated in a plasma surface treatment machine at atmospheric pressure for 20 seconds, followed by treatment with an 185nm UV-ozone lamp for 30 minutes to improve the adhesion of the silver nanowires to the surface.

[0073] The treated film-coated substrate 010 is fixed on the rotating platform of a spin coater, and a silver nanowire solution with a concentration of 0.5-1.0 mg / ml is titrated on the surface of the film-coated substrate 010 .

[0074] The silver nanowire solution on the surface of the film-coated substrate 010 is coated at high speed on the rotating platform of the spin coater to form a wet film with randomly distributed silver nanowires. The rotation speed is set at 300-500 rpm and the coating time is 8-14 minutes.

[0075] The prepared wet film was placed in an oven for heat preservation annealing treatment at a temperature of 80° C. for 40 minutes to remove the solvent and obtain a silver nanowire transparent conductive film.

[0076] After testing, the transmittance of the prepared silver nanowire transparent conductive film is 92%, and its SEM characterization is shown in the figure below. Figure 9 As shown, the square resistance is 24Ω / sq, and its square resistance distribution diagram is as follows Figure 10 As shown in FIG. 1 , the non-uniformity is 12.5%. It can be seen that compared with Examples 1 to 3, the uniformity of Comparative Example 1 is relatively low. Example 5

[0077] Reference Figure 5 The present invention provides a device for use in the above-mentioned bladeless fan-assisted metal nanowire film preparation method, including a fixed bracket 400, a compressed air spray gun 100, a bladeless fan 300 and an axial flow fan 200.

[0078] The fixing bracket 400 serves as a fixing base.

[0079] The compressed air spray gun 100 is disposed at the upper portion of the fixing bracket 400 in the height direction.

[0080] The bladeless fan 300 is correspondingly disposed below the output end of the compressed air spray gun 100 , and the bladeless fan 300 generates a downward airflow.

[0081] The axial flow fan 200 is arranged below the bladeless fan 300. The axial flow fan 200 generates an upward spiral airflow. The middle part of the axial flow fan 200 is a rotating platform 210. The upper part of the rotating platform 210 is used to install the external coating substrate 010.

[0082] In this embodiment, the compressed air spray gun 100 is arranged at the upper part of the fixed bracket 400 in the height direction. The compressed air spray gun 100 is used to atomize and spray a linear material dispersion. The working intensity adjustment of the compressed air spray gun 100 can achieve the adjustment of the atomization effect. An air pump can be provided corresponding to the compressed air spray gun 100 to adjust the working intensity of the compressed air spray gun 100 and ensure the stability of the atomization process. A protective tube can be provided between the corresponding axial flow fan 200 and the bladeless fan 300. The core working area is protected by the protective tube to reduce spillage while ensuring the stability of the airflow field.

[0083] A bladeless fan 300 is positioned below the output end of the compressed air spray gun 100 and above the film-coated substrate 010. The bladeless fan 300 generates a downward airflow, providing a stable and uniform airflow that evenly distributes the silver nanowire solution mist above the film-coated substrate 010. A first wind speed sensor 700 can be positioned at the air inlet of the bladeless fan 300 to monitor wind speed in real time.

[0084] The axial flow fan 200 is arranged below the bladeless fan 300. The axial flow fan 200 generates an upward spiral airflow. The middle part of the axial flow fan 200 is a rotating platform 210. The upper part of the rotating platform 210 is used to install the external coating substrate 010. The rotating platform 210 is a part of the axial flow fan 200 or forms a detachable fit with the axial flow fan 200. When the rotating platform 210 is a part of the axial flow fan 200, the rotating platform 210 is the central rotating shaft of the axial flow fan 200; when the rotating platform 210 forms a detachable fit with the axial flow fan 200, the middle part of the fan blade assembly of the axial flow fan 200 is a through hole 221, and a support structure is provided corresponding to the rotating platform 210. The support structure includes a lifting platform 500 and a plane bearing 600 provided on the top of the lifting platform 500. The plane bearing 600 is provided with the rotating platform 210.

[0085] The combination of the bladeless fan 300 and the axial flow fan 200 ensures that the spiral wind below the bladeless fan 300 has a relatively strong spiral wind while the vertical speed of the spiral wind is relatively low, so that the droplets produced by the compressed air spray gun 100 can have a better dispersion and uniformity effect, and ultimately provide a better film-forming effect. Example 6

[0086] Reference Figures 6 to 8 , a device, different from embodiment 5, the axial flow fan 200 includes a rotatably arranged fan blade assembly 220, the fan blade assembly 220 has a through hole 221 in the middle, and a support structure is provided corresponding to the rotating platform 210, the support structure including:

[0087] The lifting platform 500 is arranged corresponding to the through hole 221.

[0088] A plane bearing 600 is mounted on top of the lifting platform 500. The rotating platform 210 is removably mounted on the upper surface of the plane bearing 600. A rotation speed measuring unit is provided for the rotating platform 210. A first wind speed sensor 700 for measuring vertical wind speed is provided in the space above the bladeless fan 300, and a second wind speed sensor 800 for measuring vertical wind speed is provided in the space below the axial flow fan 200.

[0089] When the lifting platform 500 rises and passes through the through hole 221 , the plane bearing 600 and the fan blade assembly 220 clamp the rotating platform 210 . When the lifting platform 500 descends into the through hole 221 , the rotating platform 210 descends along with it.

[0090] In this embodiment, a lifting platform 500 is provided to provide a basis for efficient operation and also to fix the rotating platform 210. A through hole 221 is left in the middle of the blade assembly 220 of the axial flow fan 200 for the operation of the lifting platform 500. The driving form of the lifting platform 500 can be various, such as a linear motor. When working, the upper end of the lifting platform 500 penetrates the through hole 221 and descends out of the through hole 221. The top of the lifting platform 500 is a plane bearing 600. The form of the plane bearing 600 is not limited. Its lower end is connected to the lifting platform 500 so that it will not fall off. The upper end does not necessarily form a connection with the rotating platform 210. The lifting platform 500 and the blade assembly 220 can form a clamping action on the rotating platform 210.

[0091] In this embodiment, a first wind speed sensor 700 and a second wind speed sensor 800 measure vertical wind speed at two locations, respectively. While the wind speed above the axial fan 200 (i.e., below the bladeless fan 300) is the operating wind speed and is crucial for the film forming process, the wind field at this location is relatively turbulent, making wind speed measurement difficult and prone to errors. Therefore, the wind speed below the axial fan 200 and above the bladeless fan 300 are used as references to reflect the stability of the atomization process. The operating modes of the first and second wind speed sensors 700 and 800 are not limited; they can be Pitot tubes, etc., as long as they can measure wind speed. The rotational speed of the rotating platform 210 is monitored by a rotation speed measurement unit, providing a basis for adjusting the centrifugal action. It should be noted that the rotation speed measurement unit is not limited to measuring the rotational speed of the rotating platform 210 directly. When the rotating platform 210 rotates in perfect alignment with the axial fan 200, the rotation speed of the axial fan 200 is measured as the rotational speed of the rotating platform 210.

[0092] In other implementations, a droplet collection device may be provided below the axial flow fan 200. Considering that during the operation of the axial flow fan 200, not only the rotating platform 210 receives droplets, but also the fan blades receive droplets, some droplets are wasted and then recovered and reused by the droplet collection device. The droplet collection device may be an annular barrel, provided below the axial flow fan 200, or a corresponding structure may be provided on the axial flow fan 200 to directly collect droplets (e.g., a structure similar to a range hood), and the droplets collected by the axial flow fan 200 are directly collected by the droplet collection device.

[0093] In other implementations, a third wind speed sensor 900 for measuring circumferential wind speed is provided in the space above the axial flow fan 200. The airflow provided by the axial flow fan 200 has both vertical and circumferential velocity, creating a spiral effect. This spiraling airflow homogenizes the droplets produced by the compressed air spray gun 100. Measuring the circumferential wind speed with the third wind speed sensor 900 allows monitoring of the homogenization effect.

[0094] In summary, the bladeless fan-assisted metal nanowire film preparation method and device provided by the present invention can control the uniform distribution of the conductive film. The uniform airflow generated by the bladeless fan 300 has little interference with the operation of the axial fan 200. Combined with the high-speed rotating coating substrate 010, uniform coating and uniform arrangement can be achieved, ensuring the uniformity and excellent conductivity of the conductive film; the optimized production process, the bladeless fan 300-assisted preparation device is simple in design and easy to operate, and can be integrated with existing production lines to achieve efficient production of large-area uniform conductive films; good material compatibility is applicable to a variety of coating substrate 010 materials, including glass, plastic, metal, flexible materials, etc., and does not require the introduction of high temperature or chemical treatment, which is environmentally friendly and efficient; suitable for large-area preparation, by precisely controlling the wind speed and the rotation speed of the coating substrate 010, the present invention can prepare uniform conductive films on large-area coating substrates 010, which is suitable for industrial large-scale production.

[0095] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for preparing a metal nanowire film assisted by a bladeless fan, characterized in that: include: S1. Provide a compressed air spray gun, an axial flow fan, and a bladeless fan, wherein the bladeless fan and the axial flow fan are sequentially located below an output end of the compressed air spray gun, the axial flow fan generates an upward spiral airflow in a space above the axial flow fan, and the bladeless fan generates a downward airflow in a space above the axial flow fan, and the middle portion of the axial flow fan is a rotating platform; S2. Setting the output end of the compressed air spray gun to correspond to the bladeless fan; S3, preparing a linear material dispersion and transferring it to a compressed air spray gun; S4. Installing the film-coated substrate on the rotating platform, with the output end of the compressed air spray gun and the bladeless fan forming a vertical distance of 0.5-1.5 cm, and the film-coated substrate and the bladeless fan forming a vertical distance of 3-7 cm; S5. Starting the compressed air spray gun, the axial flow fan, and the bladeless fan to coat the surface of the high-speed rotating film-coated substrate to form a wet film, wherein the rotation speed of the rotating platform is 2500 to 3500 rpm, the air inlet speed of the bladeless fan is set to 3 to 4 m / s, and the operating pressure of the compressed air spray gun is 0.5 to 2.0 MPa; S6. Stop the compressed air spray gun, the axial flow fan, and the bladeless fan, remove the film-coated substrate, and perform heat treatment to form a conductive film.

2. The method for preparing a metal nanowire film assisted by a bladeless fan according to claim 1, wherein: The step S5 then includes: The wind speed below the axial flow fan and the wind speed above the bladeless fan are detected.

3. The method for preparing a metal nanowire film assisted by a bladeless fan according to claim 1, wherein: The step S5 then includes: S5.

1. Adjust the working intensity of the axial flow fan and the bladeless fan so that the ratio of the wind speed below the axial flow fan to the wind speed above the bladeless fan is between 1:1.2 and 1:1.

5.

4. The method for preparing a metal nanowire film assisted by a bladeless fan according to claim 3, wherein: The steps of S5.1 include: S5.

2. Adjust the working intensity of the compressed air spray gun according to the wind speed above the bladeless fan.

5. A device for use in the bladeless fan-assisted metal nanowire film preparation method according to any one of claims 1 to 4, characterized in that: include: Fixed bracket; A compressed air spray gun is arranged at the upper part of the fixed bracket in the height direction; a bladeless fan, correspondingly disposed below the output end of the compressed air spray gun, the bladeless fan generating a downward airflow; An axial flow fan is arranged below the bladeless fan, and the axial flow fan generates an upward spiral airflow. The middle part of the axial flow fan is a rotating platform, and the upper part of the rotating platform is used for installing an external coating substrate.

6. The device according to claim 5, characterized in that The axial flow fan includes a rotatably arranged fan blade assembly, the middle portion of the fan blade assembly is perforated, and a support structure is provided corresponding to the rotating platform, the support structure including: A lifting platform corresponding to the perforation arrangement; A plane bearing is provided on the top of the lifting platform, and the rotating platform can be detachably provided on the upper surface of the plane bearing; When the lifting platform rises and passes through the through-hole, the plane bearing and the fan blade assembly clamp the rotating platform; when the lifting platform descends to the through-hole, the rotating platform descends along with it.

7. The device according to claim 5, characterized in that A rotation speed measuring unit is provided corresponding to the rotating platform, a first wind speed sensor for testing vertical wind speed is provided corresponding to the space above the bladeless fan, and a second wind speed sensor for testing vertical wind speed is provided corresponding to the space below the axial flow fan.

8. The device according to claim 5, characterized in that A third wind speed sensor for measuring circumferential wind speed is provided corresponding to the space above the axial flow fan.

9. The device according to claim 5, characterized in that A droplet collecting device is provided below the axial flow fan.

10. The device according to claim 5, characterized in that A protective tube is provided between the axial flow fan and the bladeless fan.

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