Device and method for roll-to-roll production of flexible transparent conductive film with protective layer

Abstract

The invention discloses a device and method for roll-to-roll production of a flexible transparent conductive film with a protective layer, and the device comprises a conveying assembly line, a flowing water generation mechanism, an optical element and a graphene oxide coating mechanism. A beam of pulse laser generates two beams of pulse light with controllable intensity by utilizing a light splitting or nonlinear element, and the two beams of pulse light are respectively emitted from the two surfaces of the to-be-processed film to synchronously and controllably generate plasma expansion impact force and plasmon laser heat effect under water flow constraint; and after welding, a coating roller and a Meyer rod coating method are used for coating graphene oxide on the surface of the metal nanowire, welding and flattening of the spatially discrete metal nanowire are achieved with high production efficiency, the conductivity, oxidation resistance and stability of the metal nanowire are enhanced, and the method has wide popularization value and application prospects.

Description

Technical Field

[0001] The present invention relates to the technical field of thin film production, and relates to an apparatus and method for roll-to-roll production of a flexible transparent conductive film with a protective layer, and more specifically to an apparatus and method for roll-to-roll production of a flexible transparent conductive film with a protective layer based on laser thermal coupling. Background Art

[0002] In recent years, with more and more electronic devices gradually evolving towards being thinner, more flexible and wearable, the industrial demand for flexible conductive materials has increased sharply. Flexible transparent conductive films play an important role in fields such as touch screens, photovoltaic cells, and solar panels. Currently, there are solutions based on metal nanowire networks, carbon nanotube solutions, and indium tin oxide (ITO) solutions. Among them, indium tin oxide was once regarded as the best candidate material for preparing flexible transparent conductive films due to its excellent electrical conductivity and optical transparency. However, due to its brittle nature, high price, and complex manufacturing process, it has been gradually abandoned in the in-depth research of flexible electronics; the inherently high contact resistance of carbon nanotubes limits its further development and utilization; the transparent conductive film technology solution based on metal nanowires has characteristics such as good flexibility, low cost, and easy mass production, which has attracted great attention in the industrial and academic fields. The welding of metal nanowire networks can improve the conduction ability between different nanowires and enhance the electrical conductivity of the nanowire network; at the same time, it can ensure its stability under fatigue loads in flexible use scenarios, which is a necessary step in the production of metal nanowire transparent conductive films. However, there is a phenomenon of random distribution of nanowires during the laying process of metal nanowire networks, resulting in the situation where two or more nanowires do not actually contact, and the gaps between different nanowire nodes are different, that is, the energy required for welding is different. If only welded through the photothermal effect, too much energy will cause thermal damage or overheating and melting of the nanowires and substrate materials, and too little energy will result in only a small number of nanowire nodes being successfully welded, affecting the comprehensive electrical, optical, and mechanical properties of the film. This is a technical problem that needs to be urgently solved by those skilled in the art.

[0003] The Chinese invention patent (publication number CN115805367B) discloses a metal nanowire impact welding device and method based on the laser thermal-mechanical coupling effect. It effectively heats the node area of metal nanowires through plasmons, and compacts the nanowires by means of the impact effect of pulsed laser under the constraint of a solid constraint layer, shortening the distance between adjacent nanowires, reducing the phenomenon of virtual overlap, strengthening the heating effect, and enabling high-reliability welding operations of spatially staggered nanowires without melting the entire metal nanowires. However, this method does not give how to achieve high-efficiency laser impact combined with laser plasmon welding composite manufacturing in a roll-to-roll production line mode. During the application of laser impact force, it is necessary to lay a transparent constraint layer and a momentum transfer layer (referred to as a protective layer in the aforementioned patent), and transfer the force through the close fit of the momentum transfer layer and the nanowires; in the roll-to-roll production line mode, the surface of the flexible transparent conductive thin film with metal nanowires to be processed moves at high speed. If there is a relative displacement with the momentum transfer layer or the transparent constraint layer, friction will be generated, which will damage the metal nanowire structure and cause functional damage; moreover, the momentum transfer layer and the transparent constraint layer must be applied with high efficiency, high reliability, low cost, and high precision, and graphene oxide must be coated in a manner suitable for roll-to-roll production to meet the requirements of low-cost roll-to-roll production line applications. This results in the current laser thermal-mechanical coupling welding technology not being able to achieve large-scale and high-efficiency mass production applications. Therefore, how to achieve high-precision application of pulsed laser impact force and pulsed laser thermal effect in roll-to-roll high-efficiency production line processing and manufacturing is an urgent problem to be solved. Summary of the Invention

[0004] The object of the present invention is to provide a device and method for producing a flexible transparent conductive thin film with a protective layer in a roll-to-roll manner in view of the problems existing in the prior art.

[0005] To achieve the above object, the technical solution adopted by the present invention is: A device for producing a flexible transparent conductive thin film with a protective layer in a roll-to-roll manner includes a first conveying production line and a second conveying production line. The first conveying production line and the second conveying production line at least include a section of area close to each other, so that there is a section of fitting area close to each other between the flexible transparent conductive thin film coated with a metal nanowire layer conveyed on the first conveying production line and the momentum transfer layer coated with an absorbing layer conveyed on the second conveying production line; a water flow generating mechanism is provided on one side of the second conveying production line, and the water flow generating mechanism forms a water layer in the fitting area. On one side of the back surface of the flexible transparent conductive film where the first conveying pipeline is located, there is a first light beam scanning element, and the first light beam scanning element is used to form the outgoing light of the heating light directed at the bonding area; on one side of the water layer where the second conveying pipeline is located, there is a second light beam scanning element, and the second light beam scanning element is used to form the outgoing light of the impact force forming light directed at the bonding area; at the downstream position of the bonding area of the first conveying pipeline, there is a graphene oxide coating mechanism, and the graphene oxide coating mechanism is used to form a graphene oxide coating on the flexible transparent conductive film after welding is completed.

[0006] With the settings of the first flowing water conveying mechanism and the second flowing water conveying mechanism, this device can realize the roll-to-roll film pipeline type conveying, which is beneficial to continuous and batch production and processing; at the same time, it can also adjust the running speed and tension degree of the film to meet the requirements of film production and processing. The water flow generating mechanism can wash the bonding area between the flexible transparent conductive film and the momentum transfer layer to form a water layer with a certain thickness, and the water layer can enhance and extend the laser impact force, which is beneficial to improving the laser impact effect. The graphene oxide coating mechanism can coat a graphene oxide coating with a certain and uniform thickness on the surface of the welded metal nanowires. While enhancing the conductivity of the transparent conductive film, it can also enhance the antioxidant property of the metal nanowires, improve the fatigue strength of the metal nanowires, and reduce friction, which greatly improves the service life and stability of the transparent conductive film.

[0007] Further, the first conveying pipeline includes a first driving wheel and a first driven wheel, and a plurality of first turning wheels arranged between the first driving wheel and the first driven wheel along the conveying direction, and the bonding area is between a pair of first turning wheels; the flexible transparent conductive film is laid on the first driving wheel, the first turning wheels and the first driven wheel.

[0008] Further, the second conveying pipeline includes a second driving wheel and a second driven wheel, and a plurality of second turning wheels arranged between the second driving wheel and the second driven wheel along the conveying direction, and the area between a pair of the second turning wheels is close to the first conveying pipeline; the momentum transfer layer is laid on the second driving wheel, the second turning wheels and the second driven wheel.

[0009] Further, the graphene oxide coating mechanism includes a coating roller, a Meyer rod and a container filled with graphene oxide. Both the coating roller and the Meyer rod are located on the side of the flexible transparent conductive film coated with the metal nanowire layer and abut against the flexible transparent conductive film. The Meyer rod is located downstream of the coating roller, and the coating roller contacts the graphene oxide in the container.

[0010] Further, the metal nanowire layer is coated on the front side of the flexible transparent conductive film, and the front side of the flexible transparent conductive film faces the momentum transfer layer in the bonding area; the momentum transfer layer is a film coated with the light absorption layer.

[0011] Further, the distance between the flexible transparent conductive film and the momentum transfer layer in the bonding area is not greater than 20 microns, and the thickness of the momentum transfer layer is not greater than 1 mm.

[0012] Further, the conveying speeds of the flexible transparent conductive film and the momentum transfer layer are the same in the bonding area.

[0013] Further, a beam splitting element or a nonlinear element is further included. The beam splitting element or the nonlinear element divides a pulsed laser beam with a pulse width less than 10 ms into a heating light beam and an impact force forming light beam. The heating light beam is introduced into the first beam scanning element, and the impact force forming light beam is introduced into the second beam scanning element.

[0014] A method for roll-to-roll production of a flexible transparent conductive film with a protective layer, the method uses the device for roll-to-roll production of a flexible transparent conductive film with a protective layer as described above, and the method includes the following steps: Arrange the flexible transparent conductive film coated with the metal nanowire layer on the first conveying pipeline, and the metal nanowire layer is on the front side of the flexible transparent conductive film; Arrange the momentum transfer layer coated with the light absorption layer on the second conveying pipeline, the front side of the flexible transparent conductive film faces the momentum transfer layer, and there is a bonding area where the flexible transparent conductive film and the momentum transfer layer approach each other; Start and control the first conveying pipeline and the second conveying pipeline, so that the flexible transparent conductive film and the momentum transfer layer have the same linear speed in the bonding area; Turn on the water flow generating mechanism, wash the bonding area, and form a water layer in the bonding area; Divide a pulsed laser beam into a heating light beam and an impact force forming light beam. The heating light beam forms an outgoing heating light beam through the beam scanning element, enters the bonding area from the back side of the flexible transparent conductive film, and heats the metal nanowire layer; the impact force forming light beam forms an outgoing impact force forming light beam through the beam scanning element, acts on the light absorption layer to generate plasma expansion under water confinement to generate an impact force; the impact force acts on the metal nanowire layer through the momentum transfer layer and is coupled with the heating effect to realize the welding of spatially staggered nanowires; The completed welded flexible transparent conductive film is conveyed to the graphene oxide coating mechanism along the first conveying pipeline. The graphene oxide is coated onto the front surface of the flexible transparent conductive film by the graphene oxide coating mechanism, and a graphene oxide coating with a certain thickness and uniformity is formed on the surface of the metal nanowire layer to complete the processing of the flexible transparent conductive film.

[0015] Further, the method further includes the step of adjusting the spot size and the spot scanning trajectory of the pulsed laser, and the heating light output and the impact force forming light output are synchronously coupled and loaded on the bonding area.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The device of the present invention can be preferably applied to the high-efficiency and high-performance production and manufacturing of flexible transparent conductive films. A pulsed laser beam is divided into impact-formed light and heating light by an optical spectroscopic medium or a nonlinear element; the laser shock effect under a constrained state is realized by the water flow constraint driven by gravity from top to bottom; the tight fitting of the laser shock effect momentum transfer layer and the metal nanowires to be processed on the transparent flexible film is realized by the synergistic action of the force of the water flow on the film and the self-tension of the roll-to-roll film; the impact-formed light after beam splitting directly acts on the light-absorbing layer to generate a plasma expansion effect, and a laser impact force is generated under the constraint of the transparent water layer and acts on the front surface of the transparent conductive film; the heating light after beam splitting acts on the back surface of the transparent conductive film, and a plasmon local heating effect is generated under the action of the laser thermal effect. Through thermomechanical coupling, the welding effect of spatially discrete nanowires at the nodes is finally realized, and the surface roughness of the metal nanowire film is reduced to facilitate the subsequent coating and enhancement of graphene oxide; 2. Compared with the traditional single-pulse light heating, this method can realize the plasmon heating effect of metal nanowires that are spatially discrete and far apart under the pressing action of the pulsed light impact force, better process the flexible transparent conductive film loaded with metal nanowires that are spatially discrete and far apart, enhance its conductivity and reduce its surface roughness, providing a basis for reliable high-performance applications; compared with the existing laser pressure welding method, the roll-to-roll film tension and the water flow scouring force are used to realize the fitting between two films. After irradiating two pulsed lights with beam splitting or nonlinear conversion, the plasma expansion impact force is enhanced and extended through the water layer, realizing the roll-to-roll high-efficiency pipeline laser shock pressure and heat welding effect, with high production efficiency and realizing large-scale application; 3. In this method, the plasma impact force is enhanced and extended under the constraint of the water layer, acts on the metal nanowires through the momentum transfer layer, and is coupled with the laser plasmon heating effect, shortening the distance between adjacent nanowires, reducing the virtual overlap phenomenon, strengthening the heating effect, and realizing the highly reliable welding operation of spatially staggered nanowires; 4. In this method, the graphene oxide coating mechanism adopts the mutual cooperation of a coating roller and a Meyer rod to realize the controllable thickness of the graphene oxide coating and ensure the uniformity of coating at the same time; using this coating method also has the advantage of reducing paint waste, which has great advantages for the cost control of low-cost roll-to-roll manufacturing; 5. After the metal nanowires are welded in this method, a layer of graphene oxide is coated on the surface. Its excellent conductivity greatly improves the conductivity of the transparent conductive film; the graphene oxide coating can also prevent the reaction of the nanowire surface with oxygen in the air, thereby slowing down the oxidation process of the material. Its good mechanical properties can enhance the overall mechanical properties of the nanowires, especially in significantly improving the fatigue strength, rigidity and the stability of the overall structure of the nanowires, which has a significant improvement in the durability of the flexible transparent conductive film during the actual application process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the overall structure of an apparatus for roll-to-roll production of a flexible transparent conductive film with a protective layer according to the present invention; Figure 2 This is a schematic diagram of pulsed laser passing through beam splitting or nonlinear conversion according to the present invention; Figure 3 This is a schematic diagram of the synchronous action of impact force and plasmon laser heating according to the present invention; Figure 4 These are comparison diagrams of the relative positions and welding effects of nanowires before, during, and after the implementation of this method. Among them, (a) is a schematic diagram of the position of nanowires before the implementation of this method, (b) is a schematic diagram of the approaching of nanowires during the instantaneous process of the implementation of this method, and (c) is a schematic diagram of the welding state of nanowires after the implementation of this method; In the figure: 100, the direction of gravity; 101, flexible transparent conductive film (coated with metal nanowires); 102, the first driving wheel; 103, the first turning wheel; 104, the first driven wheel; 105, momentum transfer layer; 106, the second driving wheel; 107, the second driven wheel; 108, light absorption layer; 109, water flow generating mechanism; 110, water layer; 111, heating light; 112, the first beam scanning element; 113, heating light output; 114, impact force forming light; 115, the second beam scanning element; 116, impact force forming light output; 117, pulsed laser; 118, plasma expansion; 119, Meyer rod; 120, coating roller; 121, container. Detailed implementation manners

[0018] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0019] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "middle", "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Embodiment 1

[0020] As Figures 1 to 3As shown in the figure, a device for roll-to-roll production of a flexible transparent conductive film with a protective layer includes a first conveyor line and a second conveyor line. At least a section of the first conveyor line and the second conveyor line are close to each other, so that there is a close-fitting area between the flexible transparent conductive film 101 coated with a metal nanowire layer on the first conveyor line and the momentum transfer layer 105 coated with a light-absorbing layer 108 on the second conveyor line. A water flow generating mechanism 109 is provided on one side of the second conveyor line, and the water flow generating mechanism 109 forms a water layer 110 in the close-fitting area. A first beam scanning element 112 is provided on one side of the first conveyor line on the back of the flexible transparent conductive film. The first beam scanning element 112 is used to form a heating light output 113 directed at the close-fitting area. A second beam scanning element 115 is provided on one side of the second conveyor line on the water layer 110. The second beam scanning element 115 is used to form an impact force forming light output 116 directed at the close-fitting area. The first conveyor line is provided with a graphene oxide coating mechanism at a downstream position in the close-fitting area. The graphene oxide coating mechanism is used to form a graphene oxide coating on the flexible transparent conductive film 101 after welding.

[0021] The device of the present invention can be preferably applied to the high-efficiency and high-performance production and manufacturing of flexible transparent conductive films. Two beams of light split from the same pulsed laser are respectively used to generate a laser impact force effect (impact force forming light output) with controllable intensity and a laser thermal effect (heating light output) by using an optical beam splitting medium or a nonlinear element. The laser impact effect under constraint is realized by the water flow constraint driven by gravity from top to bottom. The close fitting of the laser impact effect momentum transfer layer and the metal nanowires to be processed on the transparent flexible film is realized by the synergistic action of the acting force of the water flow on the film and the self-tension of the roll-to-roll film. The plasma expansion effect is generated by the direct action of the split impact force forming light on the light-absorbing layer, and the laser impact force acts on the front surface of the transparent conductive film under the constraint of the transparent water layer. Through the force transmission of the momentum transfer layer film, it acts on the coated metal nanowire film synchronously with the heating laser split on the other side. The force effect reduces the gap between the spatially discrete nanowire nodes, and the plasmon local heating effect is generated under the coupling action of the laser thermal effect, and finally the welding effect of the spatially discrete nanowires at the nodes is realized, reducing the surface roughness of the metal nanowire film for subsequent enhancement of the graphene oxide coating. After the welding is completed, the device further completes the coating of the graphene oxide coating by using the conveyor line to form a protective layer on the flexible transparent conductive film.

[0022] By virtue of the arrangements of the first conveying pipeline and the second conveying pipeline, this device can achieve roll-to-roll film pipeline conveying, which is conducive to continuous and batch production and processing. At the same time, it can also adjust the running speed and tension of the film to meet the requirements of film production and processing.

[0023] The water flow generating mechanism 109 can scour the joint between the flexible transparent conductive film 101 and the momentum transfer layer 105 to form a water layer with a certain thickness, and the water layer can enhance and extend the laser impact force, which is beneficial to improving the laser shock effect.

[0024] The arrangement of the graphene oxide coating mechanism enables this device to produce a flexible transparent conductive film 101 with a self-protective layer. After the metal nanowire (layer) is welded, a layer of graphene oxide is coated on the film surface. Its excellent conductivity can greatly improve the conductivity of the transparent conductive film. In addition, the graphene oxide coating can prevent the surface of the nanowires from reacting with oxygen in the air, thereby slowing down the oxidation process of the material. Its good mechanical properties can enhance the overall mechanical properties of the nanowires, especially in significantly improving the fatigue strength, rigidity and the stability of the overall structure of the nanowire (layer), which has a significant improvement on the durability of the flexible transparent conductive film during actual application.

[0025] Furthermore, the first conveying pipeline includes a first driving wheel 102, a first driven wheel 104, and a plurality of first turning wheels 103 arranged between the first driving wheel 102 and the first driven wheel 104 along the conveying direction. The bonding area is between a pair of the first turning wheels 103; the flexible transparent conductive film 101 is laid on the first driving wheel 102, the first turning wheels 103 and the first driven wheel 104.

[0026] Through the arrangements of the first driving wheel 102, the first driven wheel 104 and the first turning wheels 103, the flexible transparent conductive film 101 can be conveyed smoothly and continuously. At the same time, the conveying speed, tension and direction of the flexible transparent conductive film 101 can be adjusted, and after turning, a bonding area parallel and corresponding to the momentum transfer layer can be formed in the gravity direction.

[0027] Furthermore, the second conveying pipeline includes a second driving wheel 106, a second driven wheel 107, and a plurality of second turning wheels arranged between the second driving wheel 106 and the second driven wheel 107 along the conveying direction. The area between a pair of the second turning wheels is close to the first conveying pipeline; the momentum transfer layer 105 is laid on the second driving wheel 106, the second turning wheels and the second driven wheel 107.

[0028] Through the arrangement of the second driving wheel 106, the second driven wheel 107 and the second steering wheel, the momentum transmission layer 105 can be conveyed smoothly and continuously, and at the same time, the conveying speed, the tension degree and the direction of the momentum transmission layer 105 can be adjusted.

[0029] Furthermore, the graphene oxide coating mechanism includes a coating roller 120, a Meyer rod 119 and a container 121 containing graphene oxide. Both the coating roller 120 and the Meyer rod 119 are located on the side of the flexible transparent conductive film 101 coated with the metal nanowire layer and are in contact with the flexible transparent conductive film 101. The Meyer rod 119 is located downstream of the coating roller 120, and the coating roller 120 contacts the graphene oxide in the container 121.

[0030] The welded metal nanowires can be conveyed to the graphene oxide coating mechanism through the first conveying pipeline, and a graphene oxide coating with a certain thickness and uniformity can be formed on its surface through the coating roller 120 and the Meyer rod 119. The mutual cooperation of the coating roller and the Meyer rod enables the thickness of the graphene oxide coating to be controllable, and at the same time ensures the uniformity of coating. Adopting this coating method also has the advantage of reducing coating waste, which has great advantages for cost control in low-cost roll-to-roll manufacturing.

[0031] Furthermore, the metal nanowire layer is coated on the front side of the flexible transparent conductive film 101, and the front side of the flexible transparent conductive film 101 faces the momentum transmission layer 105 in the bonding area; the momentum transmission layer 105 is a film coated with the light absorption layer, and the light absorption layer 108 is a sacrificial layer with light absorption materials, such as a graphite light absorption layer.

[0032] Through such an arrangement, the metal nanowire layer can be close to the momentum transmission layer 105, and at the same time, the adverse effects of the wheels on the metal nanowires during the conveying of the flexible transparent conductive film 101 can be avoided. The metal nanowire layer is a metal nanowire network, and there is a situation of random distribution of nanowires during the laying of the metal nanowires. The device and method of the present invention are to improve the welding performance and effect of these nanowires.

[0033] Furthermore, the distance between the flexible transparent conductive film 101 and the momentum transmission layer 105 in the bonding area is not greater than 20 microns, and the thickness of the momentum transmission layer 105 is not greater than 1 mm.

[0034] Furthermore, the conveying speeds of the flexible transparent conductive film 101 and the momentum transmission layer 105 in the bonding area are the same. Their conveying directions are also the same, ensuring that the pulsed light on both sides (the heating light output and the impact force forming light output) can act on the same position of the bonding area at the same time.

[0035] Further, the device further includes a beam splitting element or a nonlinear element, which splits a pulsed laser beam with a pulse width less than 10 milliseconds into a heating light 111 and an impact force forming light 114. The heating light 111 is introduced into the first beam scanning element 112, and the impact force forming light 114 is introduced into the second beam scanning element 115. Embodiment 2

[0036] A method for roll-to-roll production of a flexible transparent conductive film with a protective layer, which uses the device for roll-to-roll production of a flexible transparent conductive film with a protective layer in Embodiment 1. The method includes the following steps: Arrange the flexible transparent conductive film coated with a metal nanowire layer on the first conveyor line, and the metal nanowire layer is on the front side of the flexible transparent conductive film; Arrange the momentum transfer layer coated with an absorptive layer on the second conveyor line, with the front side of the flexible transparent conductive film facing the momentum transfer layer, and there is a fitting area where the flexible transparent conductive film and the momentum transfer layer are close to each other; Start and control the first conveyor line and the second conveyor line to make the linear velocities of the flexible transparent conductive film and the momentum transfer layer consistent in the fitting area; Turn on the water flow generating mechanism to wash the fitting area, and at the same time adjust the tension between the flexible transparent conductive film and the momentum transfer layer and the tightness in the fitting area to form a water layer, such as 0.1 - 50 mm; Split a pulsed laser beam into a heating light and an impact force forming light. The heating light forms a heating light output through a beam scanning element and is incident from the back side of the flexible transparent conductive film into the fitting area to heat the metal nanowire layer; the impact force forming light forms an impact force forming light output through a beam scanning element and acts on the absorptive layer to generate plasma expansion under water confinement to generate an impact force; The impact force is enhanced and extended under the confinement of the water layer, acts on the metal nanowire layer through the momentum transfer layer, and couples with the heating effect to achieve the welding of spatially staggered nanowires; The flexible transparent conductive film after welding is conveyed to the graphene oxide coating mechanism along with the first conveyor line. The graphene oxide is coated onto the front side of the flexible transparent conductive film along with the graphene oxide coating mechanism, and a graphene oxide coating with a certain thickness and uniformity is formed on the surface of the metal nanowire layer; Specifically, the graphene oxide in the container is carried out of the container as the coating roller rotates and is coated on the front surface of the flexible transparent conductive film. The flexible transparent conductive film continues to pass through the Mayer rod driven by the first conveying pipeline, thereby forming a graphene oxide coating with a certain thickness and uniformity on the surface of the metal nanowire layer; Under the transportation conditions of the first conveying pipeline and the second conveying pipeline, the processing of the entire flexible transparent conductive film is completed.

[0037] Further, the method further includes the step of adjusting the spot size and the spot scanning trajectory of the pulsed laser, and the heating light output and the impact force are synchronously coupled and loaded on the bonding area.

[0038] Compared with the traditional single-pulse light heating, this method can achieve the plasmon heating effect of metal nanowires that are spatially discretely separated under the pressing action of the pulsed light impact force, better process the flexible transparent conductive film attached to the spatially discretely separated metal nanowires, enhance its conductivity and reduce its surface roughness, providing a basis for reliable high-performance applications; compared with the existing laser welding method, the roll-to-roll film tension and the water flow scouring force are used to realize the bonding between two films. After irradiating two pulsed lights with beam splitting or nonlinear conversion on the upper part, the plasma expansion impact force is enhanced and extended through the water layer, realizing the roll-to-roll high-efficiency pipeline laser shock thermo-welding effect, with high production efficiency and realizing large-scale application.

[0039] Specifically, as Figures 1 - 3As shown, 100 is the direction of gravity, vertically downward. There is an overlapping area where the flexible transparent conductive film 101 and the momentum transfer layer 105 are close to each other in the direction of gravity. The flexible transparent conductive film 101 made of polyimide coated with metal nanowires is transported in a production line through the first driving wheel 102, the first turning wheel 103, and the first driven wheel 104. The metal nanowires are coated on the outer side, that is, the right side in the figure. The thin momentum transfer layer 105 made of metal aluminum is transported in a production line through the second driving wheel 106, the second turning wheel, and the second driven wheel 107. The light-absorbing layer 108 made of graphite is pre-coated on the momentum transfer layer 105. The driving wheels and driven wheels are controlled so that the two film transport lines have the same linear velocity at the overlapping area, that is, the overlapping area. The water flow generating mechanism 109 flushes the joint of the flexible transparent conductive film 101 and the metal aluminum film momentum transfer layer 105, and at the same time adjusts the tensions of the two films to achieve close fitting of the two films and form a water layer 110 with a certain thickness. A pulsed light beam is divided into a surface plasmon heating light (the heating light 111) and an impact force forming light 114 by a beam splitting or nonlinear element. The heating light 111 forms a surface plasmon heating light output (the heating light output 113) through the galvanometer of the first beam scanning element 112 and is incident from the back of the polyimide flexible transparent conductive film to heat the metal nanowire network. The impact force forming light 114 forms an impact force forming light output 116 through the galvanometer of the second beam scanning element 115 and acts on the light-absorbing layer 108 to generate a plasma expansion 118 under water confinement (see Figure 3 ), thereby generating an impact force. The synchronous coupling loading of the laser impact force and the surface plasmon laser heating in the roll-to-roll motion state is realized. The instantaneous generation of local node heating of surface plasmons by shortening the distance between discrete nanowires by the impact force finally realizes nanowire welding and flattening. The welded metal nanowires follow the first water conveying mechanism to the graphene oxide coating device. The graphene oxide is coated onto the front surface of the flexible transparent conductive film 101 from the container 121 containing the graphene oxide as the coating roller 120 rotates. The flexible transparent conductive film 101 continues to pass through the Meyer rod 119 driven by the first water conveying device, thereby forming a graphene oxide layer with a certain thickness and uniformity on the surface of the nanowire layer. The spot size and spot scanning trajectory of the pulsed laser are adjusted, and at the same time, under the condition of film production line transportation, the processing of the entire film is realized.

[0040] From Figure 4 It can be seen that for the polyimide flexible transparent conductive film processed by this method, adjacent nanowires can be effectively welded together, reducing the phenomenon of virtual overlap and realizing high-reliability welding operations for spatially staggered nanowires. Example 3

[0041] The processing method of a flexible transparent conductive film of polyethylene terephthalate (PET) coated with metal nanowires is as follows: It is transported in a production line through a first driving wheel 102, a first turning wheel 103, and a first driven wheel 104, with the metal nanowires coated on the outside; a thin momentum transfer layer 105 is transported in a production line through a second driving wheel 106, a second turning wheel, and a second driven wheel 107, and an absorptive layer 108 is pre-coated on the momentum transfer layer 105; the driving wheels and driven wheels are controlled to make the linear velocities of the two film transport lines consistent at the joint where they are joined; a water flow generating mechanism 109 flushes the joint between the flexible transparent conductive film 101 and the momentum transfer layer 105, and at the same time adjusts the tensions of the two to achieve their tight joining and form a water layer 110 with a certain thickness; a pulsed light beam is divided into a surface plasmon heating light and an impact force forming light 114 through a spectroscopic or nonlinear element; the heating light 111 forms an output of the surface plasmon heating light through a galvanometer of a first beam scanning element 112 and is incident from the back of the polyimide flexible transparent conductive film to heat the metal nanowire network; the impact force forming light 114 forms an output of the impact force forming light 116 through a galvanometer of a second beam scanning element 115 and acts on the absorptive layer 108 to generate a plasma expansion 118 under water confinement, thereby generating an impact force; the synchronous coupling loading of laser impact force and surface plasmon laser heating in a roll-to-roll motion state is realized, and the instantaneous generation of surface plasmon local node heating by shortening the distance between discrete nanowires through the impact force is finally used to achieve nanowire welding and flattening. The welded metal nanowire layer follows the first conveying production line to a graphene oxide coating device, and graphene oxide is coated onto the front surface of the flexible transparent conductive film 101 from a container 121 containing graphene oxide as the coating roller 120 rotates; the flexible transparent conductive film 101 continues to pass through a Meyer rod 119 driven by the first water conveying device, thereby forming a graphene oxide layer with a certain thickness and uniformity on the surface of the nanowire layer.

[0042] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A roll-to-roll device for producing a flexible transparent conductive film with a protective layer, characterized in that: The invention comprises a first conveying line and a second conveying line, wherein the first conveying line and the second conveying line at least comprise a region close to each other, so that the flexible transparent conductive film coated with a metal nanowire layer conveyed on the first conveying line and the momentum transfer layer coated with a light absorbing layer conveyed on the second conveying line have a region close to each other; a water flow generating mechanism is provided on one side of the second conveying line, and the water flow generating mechanism forms a water layer in the region of the contact; The first conveying line is provided with a first light beam scanning element on one side of the back side of the flexible transparent conductive film, and the first light beam scanning element is used to form a heating light output toward the bonding area; the second conveying line is provided with a second light beam scanning element on one side of the water layer, and the second light beam scanning element is used to form an impact force-forming light output toward the bonding area; the first conveying line is provided with a graphene oxide coating mechanism at a downstream position of the bonding area, and the graphene oxide coating mechanism is used to form a graphene oxide coating on the flexible transparent conductive film that has been welded.

2. The device for roll-to-roll production of a flexible transparent conductive film with a protective layer according to claim 1, characterized in that: The first conveying assembly line includes a first driving wheel and a first driven wheel, and a plurality of first steering wheels arranged between the first driving wheel and the first driven wheel along the conveying direction, and the bonding area is located between one pair of the first steering wheels; the flexible transparent conductive film is laid on the first driving wheel, the first steering wheel and the first driven wheel.

3. The device for roll-to-roll production of a flexible transparent conductive film with a protective layer according to claim 1, characterized in that: The second conveying assembly line includes a second driving wheel and a second driven wheel, and a plurality of second steering wheels arranged between the second driving wheel and the second driven wheel along the conveying direction, wherein an area between a pair of the second steering wheels is close to the first conveying assembly line; the momentum transfer layer is laid on the second driving wheel, the second steering wheel and the second driven wheel.

4. The device for roll-to-roll production of a flexible transparent conductive film with a protective layer according to claim 1, characterized in that: The graphene oxide coating mechanism includes a coating roller, a Meyer rod and a container containing graphene oxide. The coating roller and the Meyer rod are both located on a side of the flexible transparent conductive film coated with the metal nanowire layer and abut against the flexible transparent conductive film. The Meyer rod is located downstream of the coating roller, and the coating roller contacts the graphene oxide in the container.

5. The device for roll-to-roll production of a flexible transparent conductive film with a protective layer according to claim 1, characterized in that: The metal nanowire layer is coated on the front side of the flexible transparent conductive film, and the front side of the flexible transparent conductive film in the bonding area faces the momentum transport layer; the momentum transport layer is a film coated with the light absorption layer.

6. The device for roll-to-roll production of a flexible transparent conductive film with a protective layer according to claim 1, characterized in that: The distance between the flexible transparent conductive film and the momentum transfer layer in the bonding area is no more than 20 micrometers, and the thickness of the momentum transfer layer is no more than 1 millimeter.

7. The device for roll-to-roll production of a flexible transparent conductive film with a protective layer according to claim 1, characterized in that: The flexible transparent conductive film and the momentum transport layer have the same transport speed in the bonding area.

8. The device for roll-to-roll production of a flexible transparent conductive film with a protective layer according to claim 1, characterized in that: It also includes a spectroscopic element or a nonlinear element, which divides a pulse laser beam with a pulse width less than 10 milliseconds into heating light and impact force forming light, and the heating light is introduced into the first beam scanning element, and the impact force forming light is introduced into the second beam scanning element.

9. A roll-to-roll method for producing a flexible transparent conductive film with a protective layer, characterized in that: The method uses the roll-to-roll production device for a flexible transparent conductive film with a protective layer as claimed in any one of claims 1 to 8, and the method comprises the following steps: Arranging a flexible transparent conductive film coated with a metal nanowire layer on the first conveying line, wherein the metal nanowire layer is located on the front side of the flexible transparent conductive film; Arranging a momentum transfer layer coated with a light absorbing layer on the second conveying line, with the front side of the flexible transparent conductive film facing the momentum transfer layer, and a bonding area between the flexible transparent conductive film and the momentum transfer layer being close to each other; Starting and controlling the first conveying line and the second conveying line to allow the flexible transparent conductive film and the momentum transfer layer to maintain a consistent linear speed in the laminating area; Turning on the water flow generating mechanism to flush the fitting area and form a water layer in the fitting area; A pulsed laser is divided into a heating light and an impact force forming light, wherein the heating light is formed into a heating light output through a beam scanning element, and is injected into the bonding area from the back of the flexible transparent conductive film to heat the metal nanowire layer; the impact force forming light is formed into an impact force forming light output through a beam scanning element, and acts on the light absorbing layer to generate plasma expansion under water constraint, thereby generating an impact force; the impact force acts on the metal nanowire layer through the momentum transfer layer, and is coupled with the heating effect to achieve welding of spatially staggered nanowires; The welded flexible transparent conductive film is transported to the graphene oxide coating mechanism along the first conveying line. Graphene oxide is coated on the front side of the flexible transparent conductive film by the graphene oxide coating mechanism, and a uniform graphene oxide coating of a certain thickness is formed on the surface of the metal nanowire layer to complete the processing of the flexible transparent conductive film.

10. The roll-to-roll method for producing a flexible transparent conductive film with a protective layer according to claim 9, characterized in that: The method also includes the steps of adjusting the spot size and the spot scanning trajectory of the pulse laser, and the heating light output and the impact force forming light output are synchronously coupled and loaded on the bonding area.

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