CN109961877B - Plasma jet type graphene transparent conductive film substrate pretreatment method - Google Patents

Abstract

The invention discloses a pretreatment method of a plasma jet type graphene transparent conductive film substrate, which is characterized in that treatment gases such as hydrogen, oxygen, nitrogen or helium are adopted, and are subjected to treatment of an alternating current electromagnetic field to be plasmatized and sprayed to the surface of the substrate; so as to carry out surface modification pretreatment on the film base material, clean the surface, reduce the surface tension and generate polar groups on the surface. The continuous preparation method of the reel-to-reel graphene transparent conductive film by adopting the pretreatment method is also disclosed. The invention realizes the surface pretreatment of the transparent film substrate by utilizing the normal-temperature plasma jet principle, and has the advantages of simple implementation, convenient operation, favorable control, good pretreatment effect, high efficiency, capability of improving the adhesion effect of the subsequent functional layer of the film substrate and the like.

Description

Plasma jet type graphene transparent conductive film substrate pretreatment method

Technical Field

The invention belongs to the field of preparation of a graphene transparent conductive film, and particularly relates to a pretreatment method of a plasma jet type graphene transparent conductive film substrate.

Background

Graphene is an ideal photon and photoelectron material, and the graphene transparent conductive film can be widely applied to the fields of mobile phones, tablet computers, touch screen equipment and the like, and is a basic material with very wide application in the electronic industry.

The existing conventional preparation method of the graphene transparent conductive film, which is generally a CVD method, needs to grow a graphene film on a copper foil first, then a layer of organic glass protective layer is coated, then the copper foil is corroded, the graphene film is transferred to the surface of a film base material, and then the organic glass protective layer is removed. The preparation method has harsh process conditions; the operation process is complex; the method has the inherent defects which cannot be overcome, so that the yield is lower than 40%, the cost is high, the efficiency is low, and continuous production cannot be realized; and the product has only low conductive/light transmission ratio, namely low quality factor, poor conductive performance and other defects.

Patent application No. 201510481379.7 discloses a method for preparing a graphene film, which comprises the steps of soaking and stirring graphene oxide by ultrasonic waves, filtering impurities, coating a graphene oxide solution on a PET film, carbonizing, graphitizing and obtaining the graphene film. However, the method still has the defects of complex process, and difficult precise control of the carbonization and graphitization steps, which leads to poor product quality. The preparation method can not obtain a usable PET-supported graphene transparent conductive film, but the PET film and the graphene are carbonized together and then graphitized. The graphene film prepared in the way has extremely low transmittance and even completely light-tight property, poor conductivity and can not be used for transparent conductive films. Typically as a thermally conductive film.

Other methods include spin coating, dip coating, LB method (Langmuir-Blodgett), and Self-Assembly method (SA; Self-Assembly). Of these, the first two are only suitable for laboratory fabrication. The LB method and the self-assembly method can obtain ordered multilayer ultrathin films. The self-assembly method is simple and easy to implement, does not need special equipment, usually uses water as a solvent, and has the advantage of controlling the deposition process and the film structure at a molecular level. The continuous deposition of different components can be utilized to prepare two-dimensional or even three-dimensional ordered structures between film layers, and the functions of the film such as light, electricity, magnetism and the like are realized, so that the film is widely regarded in recent years. However, these two methods are used to actually manufacture transparent conductive film, and the microscopic process is very complicated, which is not suitable for mass production.

To date, there is no relatively simple, efficient, low-cost, large-scale method for producing graphene transparent conductive films.

CN201410847076.8, which was filed by the present inventors, discloses a method for producing a metal nanowire-graphene bridge-structured composite material, but does not disclose a specific method for continuously producing a roll-to-roll graphene transparent conductive film.

So far, a preparation method of a graphene transparent conductive film, which has low process requirement, high efficiency, low cost, easy control and good quality and is suitable for large-scale production, is still lacked. Become a significant problem to be solved by those skilled in the art.

In order to solve the above problems, the applicant considered to design a method for continuously preparing a roll-to-roll graphene transparent conductive film, which comprises the following steps that are sequentially and continuously performed: a. carrying out surface modification pretreatment on a transparent film substrate, cleaning the surface and reducing the surface tension; b. the surface of the film substrate is continuously coated with the multifunctional bottom coating, so that the surface tension is further reduced, and the binding force with the graphene conductive material layer is increased; c. coating at least one graphene material layer, wherein the graphene material layer at least comprises a plurality of tiny flaky graphene and metal nanowires growing on the tiny flaky graphene; d. countless mutually overlapped points among the metal nanowires coated and spread on the graphene material on the multifunctional bottom coating are welded into a whole, and all layers are fixed into a whole.

However, how to implement the step a specifically is simple to implement, convenient to operate, and beneficial to control, and the pretreatment effect and the adhesion effect of the subsequent functional layer of the film substrate are improved, which becomes a problem to be further considered and solved by those skilled in the art.

Disclosure of Invention

Aiming at the defects of the prior art, the technical problems to be solved by the invention are as follows: the method for pretreating the transparent conductive film substrate by using the plasma jet at normal temperature is simple to implement, convenient to operate, beneficial to control, good in pretreatment effect and high in efficiency, and can improve the adhesion effect of the subsequent functional layer of the film substrate.

The noun terms referred to in this application are as follows: quality factor: ratio σ of electric conductivity to light transmittance of transparent conductive film_dc/σ_opt. The transparent conductive film is required to have excellent conductivity and a ratio of light transmittance (σ) to conductivity in addition to excellent conductivity_dc/σ_opt )。σ_dcDetermination of sheet resistance, σ, of the transparent conductive film_optThe light transmittance of the transparent conductive film is determined. The quality factor can well describe the photoelectric performance of the transparent conductive film.

In order to solve the technical problems, the technical scheme of the invention is as follows:

a plasma jet type graphene transparent conductive film substrate pretreatment method is characterized in that treatment gases such as hydrogen, oxygen, nitrogen or helium are adopted, and are subjected to alternating current electromagnetic field treatment to be plasmatized and sprayed to the surface of a substrate; the method is characterized in that a film substrate (specifically a film substrate such as a PET film, a PEN film, a PMMA film, a PC film or a PI film) is subjected to surface modification pretreatment, the surface is cleaned, the surface tension is reduced, and polar groups are generated on the surface.

Thus, the bombardment of the charged particles in the plasma on the surface of the film substrate: or volatile small molecules are produced through the reaction of free radicals and ions with molecules on the surface of the film substrate to remove the weak boundary of the material surface: to cause surface micro-topography change-surface roughening: accompanied by chain scission, radical formation, etc. The plasma interacts with the surface of the film substrate material to enable the surface of the film substrate to be activated, grafted or crosslinked: introducing active groups on the surface of the material, or introducing longer branched compounds through the active groups: or a layer of cross-linking molecules is formed on the surface of the material. Oxygen is doubly introduced into the surface of the transparent film material to form a large number of oxygen-containing polar groups so that the surface of the film substrate is easily combined with the functional groups of the coating. And polymer free radicals are generated to promote the reactions of etching, exchange, grafting, copolymerization and the like on the surface layer of the fiber. In addition, as molecules, atoms and ions in the plasma penetrate into the surface layer of the material during the treatment process, the atoms on the surface of the material escape into the plasma. The process can achieve chemical and physical modification effects which are difficult to achieve by the conventional method.

The method mainly causes the change of the surface chemical characteristics of the material, the change of the macroscopic physical morphology is small or negligible, the plasma treatment only relates to the range from the surface of the material to tens of angstroms to about one thousand angstroms, and the internal matrix of the transparent film material is not changed. The material body characteristics are not influenced. Therefore, the method is particularly suitable for surface modification of organic materials such as polymers. This processing method belongs to a non-equilibrium plasma processing method.

Preferably, the method can be realized by using a gas plasma jet processing device, wherein the gas plasma jet processing device comprises a horizontally arranged substrate, the substrate is positioned above a section of horizontal path of the film substrate, an ion jet torch array formed by jet torch spray pipes is vertically and downwards fixedly arranged on the lower surface of the substrate, the jet torch spray pipes are made of insulating materials, the upper ends of the jet torch spray pipes are connected with a gas source, paired electrodes are fixedly arranged at two ends of the peripheral side surface of the jet torch spray pipes in the diameter direction, and a controller connected with the electrodes is further arranged.

Therefore, the gas source provides the processing gas and the gas pressure, so that the processing gas is sprayed downwards from the spray pipe of the spray torch, and meanwhile, the electrodes are controlled by the controller to generate an alternating current electromagnetic field, so that the glow discharge phenomenon, the capacitive coupling microwave discharge phenomenon or the inductive coupling microwave discharge phenomenon is generated in the gas spray pipe between the electrodes, so that the processing gas is sprayed out after being ionized at a lower temperature, and the modification treatment on the surface of the film substrate is realized on the premise that the temperature does not influence the violent change of the film substrate. The plasma treatment device has the advantages of simple structure, high treatment efficiency, capability of realizing non-equilibrium plasma treatment and high ionization degree; the gas has a higher degree of activation. The plasma with higher energy is obtained and maintained at lower temperature, and the method is more suitable for organic transparent film materials sensitive to temperature.

Further, the jet torch jet pipes are arranged in a plurality of rows uniformly and in a staggered mode on the substrate. Thus, the processing effect can be improved better by the ion jet torch array arranged in a staggered way.

The cross section of the electrode is arc-shaped and is attached and fixed outside the jet torch jet pipe. Thus, the formation of the electric field can be better facilitated and the effect of the electric field action can be improved.

Furthermore, two pairs of electrodes are arranged on the jet torch nozzle at intervals along the vertical direction, and the connecting line direction of each pair of electrodes is vertically arranged.

Therefore, all gas passing through the spray pipe of the spray torch can be better ensured to pass through the electric field, and a more uniform electric field treatment effect is obtained.

The invention also discloses a continuous preparation method of the roll-to-roll graphene transparent conductive film, which is characterized by comprising the following steps of sequentially and continuously: a. the method for pretreating the transparent film substrate by adopting the plasma jet type graphene transparent conductive film substrate is used for realizing surface modification pretreatment on the transparent film substrate, cleaning the surface and reducing the surface tension; b. the surface of the film substrate is continuously coated with the multifunctional bottom coating, so that the surface tension is further reduced, and the binding force with the graphene conductive material layer is increased; c. coating at least one graphene material layer, wherein the graphene material layer at least comprises a plurality of tiny flaky graphene and metal nanowires growing on the tiny flaky graphene; d. countless mutually overlapped points among the metal nanowires coated and spread on the graphene material on the multifunctional bottom coating are welded into a whole, and all layers are fixed into a whole; d, step e, continuously coating an anti-reflection optical matching layer on the surface of the film base material treated in the step e; and e, coating films, namely laminating and covering a layer of protective film on the upper surface and the lower surface of the film substrate provided with the anti-reflection optical matching layer. The continuous preparation method of the roll-to-roll graphene transparent conductive film has the advantages of simplicity in operation, low cost, convenience in control, high production efficiency, good product quality and the like.

The invention realizes the surface pretreatment of the transparent film substrate by utilizing the normal-temperature plasma jet principle, and has the advantages of simple implementation, convenient operation, favorable control, good pretreatment effect, high efficiency, capability of improving the adhesion effect of subsequent functional layers of the film substrate and the like.

Drawings

Fig. 1 is a schematic diagram of the structural principle of a gas plasma jet processing apparatus used in the implementation of a roll-to-roll graphene transparent conductive film continuous preparation method.

Fig. 2 is a schematic diagram of the structural principle of a corona treatment device adopted in the specific implementation of the roll-to-roll graphene transparent conductive film continuous preparation method.

Fig. 3 is a schematic diagram of the structural principle of a surface oxidation treatment device used in the implementation of the roll-to-roll graphene transparent conductive film continuous preparation method.

Fig. 4 is a schematic diagram of the structural principle in the top view direction of a micro gravure roller differential coating device used in the specific implementation of the roll-to-roll graphene transparent conductive film continuous preparation method.

Fig. 5 is a schematic diagram of the structural principle of a quantitative feeding transfer coating device used in the implementation of the roll-to-roll graphene transparent conductive film continuous preparation method.

Fig. 6 is a schematic diagram of the structural principle of a doctor blade coating device used in the implementation of the roll-to-roll graphene transparent conductive film continuous preparation method.

Fig. 7 is a schematic diagram of the structural principle of a slit coating device used in the specific implementation of the roll-to-roll graphene transparent conductive film continuous preparation method.

FIG. 8 is a schematic diagram of the principle of the structure of an optical pulse fusion apparatus used in the implementation of the method for continuously producing a roll-to-roll graphene transparent conductive film.

Fig. 9 is a schematic diagram of the structural principle of a normal temperature gas plasma jet welding device used in the specific implementation of the roll-to-roll graphene transparent conductive film continuous preparation method.

Fig. 10 is a schematic diagram of the structural principle of a roller hot-pressing device used in the implementation of the roll-to-roll graphene transparent conductive film continuous preparation method.

Detailed Description

The present invention will be described in further detail below with reference to a specific embodiment of a method for continuously manufacturing a roll-to-roll graphene transparent conductive film and accompanying drawings.

A roll-to-roll continuous preparation method of a graphene transparent conductive film is characterized by comprising the following steps which are sequentially and continuously carried out: a. Carrying out surface modification pretreatment on a transparent film substrate (specifically, a film substrate such as a PET (polyethylene terephthalate), PEN (PEN), PMMA (polymethyl methacrylate), PC (polycarbonate) film or PI (polyimide) film), cleaning the surface, reducing the surface tension and generating polar groups on the surface; b. the surface of the film substrate is continuously coated with the multifunctional bottom coating, so that the surface tension is further reduced, the bonding force with the graphene conductive material layer is increased, the number of polar groups is increased, and the refractive index is adjusted; c. coating at least one graphene material layer, wherein the graphene material layer at least comprises a plurality of tiny flaky graphene (generally, flaky graphene with the area of several to dozens of square microns) and metal nanowires growing on the flaky graphene; d. countless mutually overlapped points among the metal nanowires coated and spread on the graphene material on the multifunctional bottom coating are welded into a whole, and all layers are fixed into a whole.

In specific implementation, step d may further include step e, after the step d, continuously coating an anti-reflection optical matching layer on the surface of the film substrate treated in the step e. The anti-reflection optical matching layer is used for removing burrs and micro pits on the surface of the welded graphene material layer, so that the surface of a product is smooth, the transmittance is improved, and the refractive index is adjusted to enable the refractive index of each increased layer to be close to the same as the refractive index of the base material.

In specific implementation, step e may further include step f of coating films, that is, a layer of protective film is attached and covered on the upper and lower surfaces of the transparent film with the anti-reflection optical matching layer. The product is protected.

In specific implementation, the step a can realize the surface pretreatment of the base material by adopting a normal-temperature plasma jet torch array treatment mode. The plasma spraying treatment is to adopt treatment gas such as hydrogen, oxygen, nitrogen or helium, and the like, to carry out plasma treatment on the treatment gas by an alternating current electromagnetic field and to spray the treatment gas onto the surface of the base material. Bombardment of the surface of the film substrate by charge energy particles in the plasma: or volatile small molecules are produced through the reaction of free radicals and ions with molecules on the surface of the film substrate to remove the weak boundary of the material surface: to cause surface micro-topography change-surface roughening: accompanied by chain scission, radical formation, etc. The plasma interacts with the surface of the film substrate material to enable the surface of the film substrate to be activated, grafted or crosslinked: introducing active groups on the surface of the material, or introducing longer branched compounds through the active groups: or a layer of cross-linking molecules is formed on the surface of the material. Oxygen is doubly introduced into the surface of the transparent film material to form a large number of oxygen-containing polar groups so that the surface of the film substrate is easily combined with the functional groups of the coating. And polymer free radicals are generated to promote the reactions of etching, exchange, grafting, copolymerization and the like on the surface layer of the fiber. In addition, as molecules, atoms and ions in the plasma penetrate into the surface layer of the material during the treatment process, the atoms on the surface of the material escape into the plasma. The process can achieve chemical and physical modification effects which are difficult to achieve by the conventional method.

The step mainly causes the change of the surface chemical characteristics of the material, the change of the macroscopic physical morphology is very small or negligible, the plasma treatment only relates to the range from the surface of the material to tens of angstroms to about one thousand angstroms, and the internal matrix of the transparent film material is not changed. The material body characteristics are not influenced. Therefore, the method is particularly suitable for surface modification of organic materials such as polymers.

This processing method belongs to a non-equilibrium plasma processing method. In specific implementation, the gas plasma jet processing device shown in fig. 1 can be used for implementation, and the gas plasma jet processing device includes a horizontally arranged substrate 1, the substrate 1 is located above one section of horizontal path of the film substrate 2, an ion jet torch array formed by jet torch nozzles 3 is vertically and downwardly fixedly arranged on the lower surface of the substrate, the jet torch nozzles 3 are made of insulating materials, the upper ends of the jet torch nozzles 3 are connected with a gas source 4, paired electrodes 5 are fixedly arranged at two ends of the outer peripheral side surface of the jet torch nozzles 3 in the diameter direction, and a controller 6 connected with the electrodes 5 is further arranged.

Therefore, the gas source provides the processing gas and the gas pressure, so that the processing gas is sprayed downwards from the spray pipe of the spray torch, and meanwhile, the electrodes are controlled by the controller to generate an alternating current electromagnetic field, so that the glow discharge phenomenon, the capacitive coupling microwave discharge phenomenon or the inductive coupling microwave discharge phenomenon is generated in the gas spray pipe between the electrodes, so that the processing gas is sprayed out after being ionized at a lower temperature, and the modification treatment on the surface of the film substrate is realized on the premise that the temperature does not influence the violent change of the film substrate. The plasma treatment device has the advantages of simple structure, high treatment efficiency, capability of realizing non-equilibrium plasma treatment and high ionization degree; the gas has a higher degree of activation. The plasma with higher energy is obtained and maintained at lower temperature, and the method is more suitable for organic transparent film materials sensitive to temperature.

In the above gas plasma spray processing apparatus, it is more preferable that the spray torch nozzles 3 are arranged in a plurality of rows uniformly and offset on the substrate 1. Thus, the processing effect can be improved better by the ion jet torch array arranged in a staggered way. Preferably, the section of the electrode 5 is in a shape of inferior arc and is attached and fixed outside the jet pipe of the jet torch. Thus, the formation of the electric field can be better facilitated and the effect of the electric field action can be improved. Further, two pairs of electrodes are arranged on the jet torch nozzle 3, the two pairs of electrodes are vertically arranged at intervals, and the connecting line direction of each pair of electrodes is vertically arranged. Therefore, all gas passing through the spray pipe of the spray torch can be better ensured to pass through the electric field, and a more uniform electric field treatment effect is obtained.

In the step a, the surface of the base material can be pretreated in a high-voltage corona treatment mode; the high-voltage corona treatment is to generate low-temperature plasma and generate corona discharge on the surface of the plastic film substrate even if the film substrate passes through an electric field with high frequency and high voltageFree radical reactionThereby crosslinking the polymer, roughening the surface of the substrate and increasing the number of pairsPolar solventThe ions penetrate into the surface of the body to be printed to destroy the molecular structure, oxidize and polarize the molecules of the treated surface, and attack the surface by the ion shock, so as to increase the wettability of the subsequent layersThe ability to adhere.

The high-voltage corona treatment mode can be realized by adopting the corona treatment device shown in fig. 2, the corona treatment device comprises a rectangular shell 7, a treatment working area is formed by a shell inner cavity, a substrate inlet is formed in one side of the working area, a substrate outlet is formed in the other side of the working area, a space for enabling the film substrate 2 to pass through and generating an electric field is formed in the shell inner cavity between the substrate inlet and the outlet, a corona cathode rotating roller 8 is horizontally arranged in the inner cavity of the shell 7, the corona cathode rotating roller 8 is arranged in the advancing direction perpendicular to the film substrate 2, a metal material is arranged inside the corona cathode rotating roller 8 and forms an electric field cathode, electric field anodes 9 are arranged at intervals in the vertical direction of the corona cathode rotating roller 8, and the electric field anodes and the electric field cathodes are respectively connected with a controller 10 arranged outside the shell. Thus, the roller is used for driving the plastic film substrate to move forward and simultaneously serves as an electric field formed between the cathode and the anode, corona discharge is generated under the control of the controller, and low-temperature plasma is generated by air breakdown to realize surface treatment of the plastic film substrate.

In the corona treatment device, preferably, the electric field anode 9 includes a plurality of metal electrode plates arranged at intervals along the advancing direction of the plastic film substrate, and one side edge of the metal electrode plate close to the roller is sharp and parallel to the corona cathode roller 8 for generating the electric field by discharging. Therefore, one cathode corresponds to a plurality of groups of parallel sharp plate-shaped anodes, a plurality of groups of parallel and spaced discharge sparks can be better generated, the defect of unbalanced treatment effect caused by a single anode corona discharge mode can be avoided, and the treatment effect is improved. Furthermore, corona cathode rotating rollers and corresponding electric field anodes are two groups arranged at intervals along the advancing direction of the base material and used for generating two electric fields, and the corona cathode rotating rollers of the two electric fields are horizontally arranged and the corresponding electric field anodes are respectively positioned at the upper side and the lower side. Therefore, the upper surface and the lower surface of the film substrate can be simultaneously subjected to corona treatment without adjusting the direction by redundant intermediate rollers, and tensioning is facilitated.

In the step a, the surface of the film base material can be pretreated by a surface oxidation treatment method, so that the surface of the film base material is subjected to oxidation reaction to increase the number of polar groups. Specifically, flame method, acid treatment, etc. The surface oxidation treatment can increase the polarity of the polymer surface to improve the wettability to water, the adhesive strength and the printability. The flame oxidation of the surface increases the polarity of the surface of the transparent film, thereby improving the wettability, adhesion and coatability to water. The surface of the transparent film is treated by gas flame in the air, so that the surface is oxidized to generate carbon-oxygen bonds, and the transparent film is easy to combine with the coating.

The surface oxidation treatment method can be realized by adopting the surface oxidation treatment device shown in fig. 3, the surface oxidation treatment device comprises a flame nozzle base plate 11, the flame nozzle base plate 11 is arranged above a section of horizontal path of the film base material 2 in parallel, flame nozzles 12 which are arranged in rows along the width direction of the film base material are vertically arranged downwards on the lower surface of the flame nozzle base plate 11, the flame nozzles 12 are connected with an air source 13 through air pipes, and the air pipes are provided with flow control switch valves 14. Therefore, the distance of flame sprayed out by the flame nozzle can be controlled by adjusting the flow control switch valve, so that the flame nozzle can just bake and heat the surface of the film base material within a bearing range, the film base material generates oxidation reaction, a large amount of polar groups are generated, and the subsequent process is easy to combine with the coating. Has the advantages of simple structure, convenient and fast treatment, high efficiency and the like.

In the surface oxidation treatment apparatus, it is preferable that the flame nozzles 12 are distributed in a plurality of rows at intervals along the advancing direction of the film base material, and each row of the flame nozzles is arranged in a staggered manner. Thus, the uniform baking oxidation effect on the surface of the film substrate can be better ensured. Further, the gas source 13 is a hydrogen gas source, so that the reaction substance generated by combustion is water, and the performance of the film substrate is not affected. Further, an atomizing nozzle 12a is further provided between the flame nozzle 12 and the film base material 2 at a position on the film base material inlet side, the spraying direction of the front end of the atomizing nozzle 12a is the same as the advancing direction of the film base material 2, the rear end of the atomizing nozzle 12a is connected to a container 15 through a delivery pipe, an oxidizing acid solution is provided in the container, and a booster pump 16 and a control valve 17 are further provided in the delivery pipe. Therefore, the oxidizing acid solution and the oxidizing acid solution can be sprayed out of the atomizing nozzle under the control of the booster pump and the control valve, fall onto the surface of the film base material under the thrust of the flame nozzle, and quickly generate oxidation reaction under the action of flame to generate a large amount of polar groups, so that the number of the polar groups is increased, and the subsequent combination effect of the film base material and the coating is greatly improved.

In the step b, the multifunctional primer coating can be prepared by continuously coating a multifunctional primer coating (preferably water as a solvent) composed of one or more of nano zinc oxide particles, nano titanium dioxide particles, nano silicon dioxide particles and nano zirconium oxide particles with the total content of 0.2-5% and water-based acrylic resin with the total content of 3-20% on the surface of a film base material, and drying the coating.

The preparation method comprises the steps of dissolving the materials in a polar solvent (the polar solvent can be water preferably), uniformly mixing to obtain the multifunctional base coat paint, coating the multifunctional base coat paint on the surface of a film substrate in a coating mode, and drying (drying in an oven can be adopted) to obtain the multifunctional base coat. By adopting the multifunctional bottom coating of the component, the waterborne acrylic acid is beneficial to the bonding of subsequent functional layers, can provide more polar groups, and can better reduce the surface tension of a film substrate, so that the post-process waterborne coating can be easily spread to form a uniform conductive coating; the conductive layer and the base film can achieve extremely high bonding strength (for example, embedded physical bonding is realized by combining a later hot pressing process); meanwhile, the refractive index of the film layer is adjusted by the nano particles to be completely matched with the refractive index of the transparent conductive film layer coated subsequently. The transparent conductive film layer can not show dark shadows due to different refractive indexes of the transparent conductive film layer and the bottom layer after the pattern is etched; namely, the multifunctional bottom coating obtained in the step b has the function of eliminating shadow.

In the step b, the multifunctional bottom coating layer can be prepared by a mode of micro gravure roller differential coating. In this embodiment, contact coating, i.e., a micro-mesh roll, is used as the coating metering roll, and the number of lines is in a wide range. The micro anilox roller is arranged in the precise bearing seat and is directly driven to rotate by a motor, and the rotating direction is opposite to the film feeding direction. The coating is to apply the coating on the surface of the film in a shearing mode. Contact coating means that there is no back pressure rubber roll, eliminating some potential disadvantages due to back pressure roll pressurization.

The mode can also be that a coating roll and a coating back roll are arranged in parallel and are driven by a motor to rotate at different speeds respectively, so that the rotating speed of the coating roll is greater than that of the coating back roll, a film substrate is driven by the coating back roll to move forwards and passes between the coating roll and the coating back roll, and the coating provided on the surface of the coating roll is extruded to the surface of the film substrate passing through the coating back roll by virtue of the different speeds. The method has the advantages of accurate coating amount, easy coating amount change, easy coating surface adjustment, high transfer coating quality, simplicity, reliability, good repeated stability, convenient control, high efficiency and the like.

Specifically, the differential coating of the micro gravure roll can be realized by adopting a differential coating device of the micro gravure roll shown in fig. 4, the differential coating device of the micro gravure roll comprises a coating roll 18 and a coating back roll 19 which are arranged in parallel, the coating roll 18 and the coating back roll 19 are respectively in transmission connection with a power motor and can be driven by the power motor to rotate synchronously at a differential speed, and the rotation speed of the coating roll 18 is greater than that of the coating back roll; the film substrate passes between the coating roller 18 and the coating back roller 19, so that the passed film substrate is tensioned by the coating back roller and is attached to the coating roller 18; the surface of the coating roller 19 is provided with a micro groove 20 with the width of 0.015mm-0.5mm along the length direction, and a coating feeding device connected with the micro groove 20. Therefore, differential synchronous coating control can be better realized, and the device is simple in structure and convenient to implement.

In the differential coating device for the micro gravure roll, the length of the coating back roll 18 is preferably shorter than that of the coating roll and is consistent with that of the micro grooves on the coating roll. Thus, the full-surface coating of the film substrate can be better ensured. Further, the coating feeding device comprises a coating cavity located inside the coating roller 18, the bottom of the micro groove 20 is provided with a through hole 21 communicated with the coating cavity, a rotating shaft at one end of the coating roller is a hollow feeding rotating shaft 22 and communicated with the coating cavity, the outer end of the feeding rotating shaft is connected with a feeding pipeline through a rotary sealing piece 23, and the other end of the feeding pipeline is connected with a coating container 25 through a feeding pump 24. Can rely on the charge pump material and provide certain pressure like this for in the coating roller coating permeates out the miniature pit from the through-hole under the pressure effect in, and then by the differential coating to the film substrate on, have simple structure, the convenient and fast controllable advantage of material loading. Further, the through holes 21 are uniformly arranged along the length direction of the micro grooves. Therefore, the coating which permeates out of the micro groove is more uniform, and the coating uniformity is improved. Further, the micro grooves 20 on the coating roller 18 are spiral grooves, so that the contact area between the micro grooves and the film substrate can be increased, and the coating effect can be improved better. Further, a material receiving box 26 is arranged below the coating roller and the coating back roller, and the material receiving box 26 is positioned above the coating container 25 and is connected with the coating container 25 through a recovery pipeline 27. Therefore, the material can be collected and recycled by means of self weight to form circular coating, the utilization efficiency of the coating is improved, the sanitation of the field environment is kept, and the cleaning is favorably realized.

In the step b, the multifunctional base coat can also be realized by adopting a quantitative feeding transfer coating mode. I.e., fed using a metering roll and then transfer coated onto the film substrate using a transfer roll. The mode has the advantages of simple structure, convenient control, easy and accurate control of the thickness of the coating, uniform dispersion of the coated material and the like.

The quantitative feeding transfer coating method can be realized by using the quantitative feeding transfer coating device shown in fig. 5, which comprises a quantitative feeding roller 28, a plurality of micro-pits with preset volume are continuously and uniformly distributed on the surface of the quantitative feeding roller 28, the diameter range of the micro-pits is 0.002mm-5mm, the quantitative feeding transfer coating device also comprises a feeding mechanism connected with the quantitative feeding roller 28, a transfer roller 29 is arranged on one side of the quantitative feeding roller 28 in parallel and is attached, an application back roller 30 is arranged on one side of the transfer roller 29 opposite to the quantitative feeding roller in parallel and is attached, the film substrate 2 passes between the transfer roller 29 and the application back roller 30, so that the passing film substrate 2 is tensioned by the application back roller and is attached to the transfer roller, and the quantitative feeding roller 28, the transfer roller 29 and the application back roller 30 are arranged in a linkage manner. Thus, when the device is used, the coating is firstly loaded on the surface of the quantitative feeding roller by the loading mechanism and then quantitatively transferred and coated on the film substrate between the transfer roller and the coating back roller through the transfer roller, so that the device has the advantages of simple structure, convenient control and capability of realizing precise quantitative coating control.

Among the above-mentioned synchronous accurate coating device, the better selection is, feed mechanism is including setting up in a sealed feeding box 31 that quantitative feed roller deviates from the reverse one side of transfer roller, and it is provided with the coating opening that is used for with the laminating of quantitative feed roller surface to correspond quantitative feed roller on the side of the closed feeding box, all is equipped with on the upper and lower arris of coating opening and is the scraper 32 of certain angle with quantitative feed roller axial tangent line. With such a feed mechanism, the coating is placed in the closed feed magazine 31 and applied to the surface of the metering roll through the coating openings as the metering roll rotates, and then the thickness of the coating is controlled by adjusting the distance between the edge of the doctor blade 32 and the feed roll 28, enabling accurate metering. And has the advantages of simple structure, easy control, etc. Furthermore, the two ends of the closed upper material box 31 are connected with an upper material box support 33 downwards, and the lower end of the upper material box support 33 is hinged on the rack. Therefore, the feeding box can be conveniently opened and closed for maintenance by rotating the feeding box support. Further, the metering roll 28, the transfer roll 29 and the application backing roll 30 are provided with gears on their respective shafts and engaged with each other, and are coupled by any one of the gears and a motor (the gears and the motor are not shown in the drawings) to realize a linkage. Therefore, the synchronous linkage transmission control device is simple in structure and realizes synchronous linkage transmission control. Further, transfer roller 29 both ends down erection joint has telescopic machanism 34, and telescopic machanism 34 stiff end is fixed in the frame, and telescopic machanism 34's flexible end upwards connects at the transfer roller tip, the gear position at transfer roller both ends is higher than the gear position at ration feed roller and coating backing roll both ends for when the transfer roller drives to reset downwards by telescopic machanism, transfer roller both ends gear can fall into downwards and mesh between the gear at feed roller and coating backing roll both ends. Thus, the arranged telescopic mechanism can conveniently jack the whole transfer roller upwards so as to facilitate the work of cleaning, maintenance, speed regulation and the like; simultaneously, the unique structure can ensure that the lifting of the transfer roller does not influence the re-meshing transmission of the three gears, so the use is very convenient and fast. Furthermore, a receiving magazine 35 is arranged below the metering roll 28, the transfer roll 29 and the application backing roll 30, the metering roll and the transfer roll projecting vertically downwards falling within the receiving magazine 35. Therefore, the material receiving box can be used for receiving and recycling materials, the utilization efficiency of the coating is improved, and the environmental sanitation of a working site is ensured.

In the step b, the multifunctional base coat can be arranged by adopting a blade coating mode. Namely, coating the coating on the surface of a film substrate by a feeding roller, and scraping by a scraper to obtain the multifunctional base coating with the required thickness. In this way, the position of the doctor blade can be controlled by means of adjustment, so that the obtained thickness of the functional layer can be better controlled.

Specifically, the blade coating mode can be realized by adopting the blade coating device shown in fig. 6, the blade coating device comprises a feeding roller 36 and a feeding back roller 37 which are horizontally arranged in parallel, the feeding roller 36 is connected with a feeding mechanism and realizes coating feeding, a horizontally arranged blade 38 is also arranged over the feeding roller 36, a blade back roller 39 is arranged over the feeding back roller 37, the blade edge of the blade 38 is arranged over the blade back roller, and the moving path of the film substrate 2 has a path section moving vertically upwards and passes between the feeding roller 36 and the feeding back roller 37 and between the blade edge of the blade 38 and the blade back roller 39. Like this, when film substrate 2 vertical upward movement, earlier through between material loading roller and the material loading backing roll to realize the material loading by the material loading roller, then when passing through the scraper, rely on the scraper to scrape out the dope layer of required thickness. The thickness of the coating layer can be better scraped in a vertical scraping mode, the scraped coating can conveniently fall downwards and is accumulated on the surface of the film substrate, the thickness of the coating on the surface of the film substrate entering the scraper is enough, and the scraped coating layer has no pit defect; and redundant coating can drop down to the feeding roller and be recycled.

In the above blade coating apparatus, it is preferable that the surface of the feeding roller 36 is continuously and uniformly distributed with a plurality of micro-pits with preset volume, and the diameter of the micro-pits is in the range of 0.05mm-5 mm. In this way, it is convenient to better rely on the micro-crater to deposit the coating to better effect coating of the film substrate. Further, feed mechanism includes a coating cartridge 40 that sets up in the loading roller outside, and the coating cartridge 40 side is gone up and is provided with the coating opening that is used for with the laminating of loading roller surface corresponding the loading roller, all is equipped with on the upper and lower edge of coating opening and is the scraper of certain angle with loading roller axial tangent line. By adopting the feeding mechanism, the coating is arranged in the coating box, and is coated on the surface of the feeding roller through the coating opening when the feeding roller rotates, and then the thickness of the coating is controlled by scraping through the scraper, so that accurate quantitative feeding can be realized. And has the advantages of simple structure, easy control, etc. Further, a paint cartridge mounting bracket 41 is connected to the paint cartridge 40 in an outward and downward direction, and the lower end of the paint cartridge mounting bracket 41 is hinged to the frame. Like this, can conveniently open the coating cartridge through rotatory coating cartridge installing support upset and carry out the material loading. Further, a recovery box 42 is arranged below the feeding roller, so that falling coatings can be recovered conveniently, and the on-site environmental sanitation can be kept conveniently.

In the step b, the multifunctional primer layer can be disposed by slot die coating (slot die). The method is characterized in that the coating is arranged in a coating box body, a slit corresponding to the width of the film substrate is arranged on the coating box body, and then the coating is extruded and coated on the surface of the film substrate by controlling pressure. The mode realizes control by controlling pressure, can realize pre-measured coating, can realize single-layer and double-layer coating when the wet coating thickness reaches 1um or even is thinner, and has the speed of 300 m/min, is suitable for roll-to-roll continuous coating process, has high control precision of the coating thickness, and has the advantages of simple implementation and convenient control.

The slit type coating device shown in fig. 7 may be specifically used for realizing the slit type coating method, and the slit type coating device includes a coating box 43, a coating plate 44 is downward arranged at the lower end of the coating box 43, a slit for coating is downward arranged in the coating plate 44, the slit for coating is arranged right opposite to the width direction of a section of the horizontal section of the path of the film base 2, a slit coating back roll 45 is arranged right opposite to the lower side of the film base, the slit coating back roll 45 supports and abuts against the film base 2 at the outlet of the slit for coating, an inner cavity of the coating box 43 is sealed and filled with a coating, an air pipe 46 and an air pressure source are arranged at the upper end of the coating box in an upward communication manner, and an air pressure control valve 47 is arranged on the air pipe. Like this, rely on the air pressure control valve to adjust the air input, and then adjust coating box body internal pressure for coating can be extruded to the film substrate with stable pressure all the time on, guarantees the homogeneity of coating.

In the slit type coating apparatus, it is more preferable that the lower end side surface of the coating plate 44 is formed in a downward semicircular shape, and the slit for coating is opened at a central position of the lower end of the semicircular shape. Therefore, the generation of scratching can be avoided, and the stability of coating is ensured. Further, a pressure sensor 49 is arranged between the rotating shaft at the two ends of the slit coating back roller 45 and the mounting bracket 48, and the pressure sensor 49 is connected with the air pressure control valve 47. Therefore, the pressure applied to the slit coating back roll can be detected by the pressure sensor, the air pressure control valve is controlled by feedback, the coating is extruded out at stable and balanced pressure, and the coating is guaranteed to be balanced and stable. Furthermore, a uniform pressing roller 50 is further arranged above the film substrate on one side of the coating box body 43 along the advancing direction of the film substrate, a uniform pressing back roller 51 is further arranged below the uniform pressing roller 50, the film substrate 2 is clamped between the uniform pressing roller 50 and the uniform pressing back roller 51, and the uniform pressing roller 50 and an upward pressure mechanism 52 are connected and installed on the machine frame. Therefore, the coating extruded through the coating slit can be uniformly extruded when passing through the leveling roller, and the reliability and uniformity of coating can be better ensured. The coating quality is improved. Further, the surface of the even pressing roller 50 is provided with a non-stick coating 53, so that the coating quality is prevented from being influenced by adhesion. By adopting the mode, the coating with the preset amount is easy to realize; the wet coating thickness can reach 1um, and even thinner; can realize single-layer and multi-layer coating

In the step c, the graphene material layer is formed by continuously coating a graphene material layer coating, wherein the main effective component of the graphene material layer coating comprises graphene on which metal nanowires parallel to a graphene plane grow, and a (small amount of) resin serving as an adhesive. Specifically, the composite material for preparing a graphene bridge structure and the preparation method thereof disclosed in the granted patent CN201410847076.8 by the present inventors can be used. The main effective components comprise metal nanowires, metal nanoparticles and graphene micro-sheets with square micron-sized areas, so that the conductivity can be better improved after the graphene micro-sheets are welded into a bridge structure. The graphene material layer may be disposed in the step c in a manner similar to that of the multifunctional primer layer, i.e., the material is dissolved in a polar solvent and then coated on the multifunctional primer layer by coating, so that details are not described herein.

And d, realizing the welding of the graphene material layer by adopting a high-frequency program control pulse xenon lamp light pulse welding mode. The method comprises the steps of irradiating a graphene material layer on a film base material by means of high-frequency pulse control (preferably over 50HZ frequency) of a xenon lamp, and pressurizing by combining a pressure roller, so that metal nanowires and metal nanoparticles absorb and convert illumination heat energy, then are welded under the action of pressure, and fix the graphene material layer into a whole. The optical pulse welding mode has the advantages of simple implementation, convenient control, reliable quality and the like. The method is particularly suitable for welding the graphene material layer by utilizing the characteristic that the silver nano material is easy to absorb and convert heat under high-power pulse illumination by utilizing the nonlinear characteristic of the silver nano material when the nano wire and the nano particle are made of silver materials.

Specifically, the optical pulse welding mode can be realized by using the optical pulse welding device having the structure shown in fig. 8, the optical pulse welding device includes two xenon lamp devices connected to the high-frequency pulse control module, the two xenon lamp devices are arranged in parallel at intervals in front and back of a horizontal section of the path of the film base material 2, the irradiation directions of the two xenon lamp devices are downward and directly opposite to the film base material, a welding press roller 54 is arranged above the film base material between the two xenon lamp devices, a welding back roller 55 is correspondingly arranged below the welding press roller 54, and the film base material 2 is clamped by the welding press roller 54 and the welding back roller 55. Like this, the film substrate is earlier through a xenon lamp device, under the high-frequency pulse illumination of xenon lamp, make metal nano wire and metal nanoparticle absorb conversion illumination heat energy and accomplish preliminary butt fusion, then with the pressure of compression roller for the butt fusion, make the material can use the splice point to further extrude closely knit as an organic whole and obtain required lamellar structure, then shine through a xenon lamp device once more and ensure that each splice point position accomplishes lapped reliability, avoid the extrusion and the splice point disconnection that leads to, the electric conductive property that guarantees to make the graphite alkene material layer meets the demands. Therefore, the device has the advantages of simple structure, convenience in control, excellent welding effect, excellent conductivity of the obtained graphene material layer and the like.

In the above optical pulse fusion apparatus, it is preferable that the xenon lamp device includes a housing 56 which is integrally formed in a horn shape with a downward opening, multiple rows of xenon lamps 57 are uniformly spaced in the housing 56, and each row of xenon lamps 57 is disposed along the width direction of the film substrate and arranged in a staggered manner. Therefore, the uniformity of illumination can be better ensured, the balance of heat absorption of the graphene material is ensured, and the consistency of the electric conductivity of the obtained graphene material layer at all positions is ensured. Further, the fusing press roller 54 is connected to the frame via a press mechanism 58. Therefore, the pressure mechanism 58 can be used for controlling the compression roller for welding to apply pressure, the pressure is guaranteed to be adjusted moderately, and the quality of the prepared graphene material layer is improved.

And d, realizing the welding of the graphene material layer by adopting a normal-temperature plasma self-limiting welding mode.

The normal-temperature plasma self-limiting welding treatment is to adopt treatment gases such as hydrogen, oxygen, nitrogen or helium, to carry out plasma treatment on the treatment gases through an alternating current magnetic field and to spray the treatment gases to the surface of the graphene material layer. Energy is provided through bombardment of charge energy particles in plasma on the surface of the graphene material layer, so that the metal crossing point of the metal nanowire growing on the graphene in the graphene material layer and the metal nanowire growing on the adjacent graphene is excited and polarized by a plasma field due to the interval generated by the coating clamped between the metal nanowire and the metal nanowire, a local 'hot spot' is formed at the interval, and the nano-scale welding is performed at the crossing point of the metal nanowires. The achievement of fusion bonding results in a sharp increase in conductivity. The method is simple to operate, reliable and stable in welding, low in treatment temperature, small in influence on the film base material and the graphene material, and free of triggering the modification of the film base material.

This processing method belongs to a non-equilibrium plasma processing method. Specifically, the normal temperature gas plasma jet welding device shown in fig. 9 can be used, the normal temperature gas plasma jet welding device comprises a mounting plate 59 horizontally arranged, the mounting plate 59 is located above one section of horizontal path of the film substrate 2, a tubular gas nozzle 60 is vertically and downwards fixedly arranged on the lower surface of the mounting plate 59, the gas nozzle 60 is made of an insulating material, a gas source container 61 is connected to the upper end of the gas nozzle 60, an anode electrode and a cathode electrode 62 are fixedly arranged at two ends of the peripheral side surface of the gas nozzle 60 along the diameter direction, and a controller 63 connected with the anode electrode and the cathode electrode 62 is further arranged.

Therefore, the gas source container provides the processing gas and the gas pressure, so that the processing gas is sprayed downwards from the gas nozzle, and meanwhile, the anode electrode and the cathode electrode are controlled by the controller to generate an alternating current electromagnetic field, so that a glow discharge phenomenon, a capacitive coupling microwave discharge phenomenon or an inductive coupling microwave discharge phenomenon is generated inside the gas nozzle between the anode electrode and the cathode electrode, so that the processing gas is sprayed out after being ionized at a lower temperature, and the welding treatment on the graphene material layer on the surface of the film substrate is realized on the premise that the temperature does not influence the drastic change of the film substrate. The device has the advantages of simple structure, high treatment efficiency, capability of realizing non-equilibrium ion treatment and high ionization degree; the gas has a higher degree of activation. The plasma with higher energy is obtained and maintained at lower temperature, and the method is more suitable for organic transparent film materials sensitive to temperature.

In the normal temperature gas plasma jet welding apparatus, it is preferable that the gas nozzles 60 are arranged in a plurality of rows uniformly and offset on the mounting plate 59. Thus, the treatment effect can be improved by arranging the plurality of rows of gas nozzles in a staggered manner. The sections of the anode electrode and the cathode electrode are in the shape of inferior arcs and are attached and fixed outside the gas nozzle. Thus, the formation of the electric field can be better facilitated and the effect of the electric field action can be improved. Further, two pairs of anode electrodes and cathode electrodes are arranged on the gas nozzle 60, the two pairs of electrodes are arranged at intervals along the vertical direction, and each pair of anode electrodes and each pair of cathode electrodes are arranged vertically along the connection line direction. Therefore, all gas passing through the gas nozzle can be better ensured to pass through the electric field, and a more uniform electric field treatment effect is obtained.

In the step d, the heating welding can also be realized by adopting a roller hot-pressing mode, namely, after the roller is heated, the film base material passes through the roller and is attached to the pressing roller, the film base material is heated by the roller and then pressed by the pressing roller, and the metal nano wire, the metal nano particle and the graphene material are dissolved, solidified and pressed into a whole by the high-temperature hot-pressing mode, so that the graphene material layer with stable and uniform parameters and performance is obtained. This kind of mode can do benefit to streamlined production, does benefit to and improves the butt fusion effect, improves electric conductive property, can make each layer closely knit by the pressfitting better, improves the physical parameter uniformity.

The roller hot-press type welding method can be specifically realized by adopting the roller hot-press device shown in fig. 10, the roller hot-press device comprises a roller 64, a press roller 65 and a roller heating mechanism for heating the roller, the press roller 65 is arranged on one side of the roller in parallel, two ends of the press roller 65 are arranged on the telescopic end of a telescopic mechanism 66, the fixed end of the telescopic mechanism 66 is fixed on the rack, and the telescopic direction of the telescopic mechanism 66 is just opposite to the direction of the roller 64. The device has the advantages of simple structure, capability of realizing flow line production, convenience in pressure regulation and the like.

In the roller hot press device, in a more preferable embodiment, the roller heating mechanism includes a roller inner core made of a metal material, and further includes a heating coil 67 located outside one side of the roller, and the heating coil 67 is configured to generate a magnetic field and generate an induced current in the roller inner core inside the roller when the roller rotates to realize heating. Like this, utilize the rotation of cylinder self to produce heat energy, have simple structure, do benefit to the setting, conveniently through advantages such as heating coil current control heating degree. Further, the telescopic mechanism 66 may be an air cylinder, and has a simple structure and low cost, and is beneficial to setting and controlling.

In the step e, the anti-reflection optical matching layer is formed by continuously coating anti-reflection optical matching coating paint and comprises the following modes: a. one or more of the following resins are used: tetrafluoroethylene and perfluorinated alkyl vinyl ether copolymer amorphous resin (such as DuPont amorphous resin AF, AF1600/AF2400 and SPC-1410), Fluorinated Ethylene Propylene (FEP), and b, one or more of nano zinc oxide particles, nano titanium dioxide particles, nano silicon dioxide particles and nano zirconium oxide particles with the total content of 0.2-5%, and the coating is prepared from a fluorine-containing solvent to be an anti-reflection optical matching coating paint;

or one or more of a, modified aliphatic urethane acrylate, 20 ten thousand vinyl polysiloxane with relative molecular weight, 5 thousand to 6 thousand mercapto polysiloxane with relative molecular weight and 5 ten thousand to 6 ten thousand acrylic acid fluorine-silicon polymer with relative molecular weight are used; b. one or more of nano zinc oxide particles, nano titanium dioxide particles, nano silicon dioxide particles and nano zirconium oxide particles with the total content of 0.2-5%; c. coating the three materials with UV (ultraviolet) for curing to obtain an anti-reflection optical matching layer;

or one or more of a, water-soluble acrylic resin, b, nano zinc oxide particles, nano silicon dioxide particles, nano titanium dioxide particles and nano zirconium oxide particles with the total content of 0.2-5 percent; the two materials are mixed with water paint and are coated and dried to obtain the anti-reflection optical matching layer.

Like this, can improve graphite alkene film surface properties uniformity better, can adjust better and reduce the refracting index that obtains graphite alkene film, and reduce the reflection and increase the transmittance, improve graphite alkene film performance.

In step e, the antireflective optical matching layer may be disposed in the same manner as the multifunctional primer layer, and will not be described in detail here.

In the method, step f, namely the film coating step, is to cover and bond a protective film on the upper surface and the lower surface of the film base material respectively after the anti-reflection optical matching layer is arranged. The prepared product is convenient to protect the graphene film before formal use. In specific implementation, the film coating step is realized by adopting a mode of extruding by a pair of compression rollers.

The inventionThe graphene transparent conductive film for industrial production has ultrahigh quality factor sigma_dc /σ_optThe content is usually over 1000, preferably 1200-1500, and most preferably 1800. In contrast, the figure of merit, σ, for ordinary few-layer graphene_dc/σ_optAbout 550 or so. Quality factor sigma of ITO_dc/σ_optAbout 300-350, the quality factor sigma of polycrystalline graphene prepared by CVD method_dc/σ_optOnly about 100-180 deg.f.

Claims (4)

1. A roll-to-roll continuous preparation method of a graphene transparent conductive film is characterized by comprising the following steps which are sequentially and continuously carried out: a. carrying out surface modification pretreatment on a transparent film substrate, cleaning the surface and reducing the surface tension; b. the surface of the film substrate is continuously coated with the multifunctional bottom coating, so that the surface tension is further reduced, and the binding force with the graphene conductive material layer is increased; c. coating at least one graphene material layer, wherein the graphene material layer at least comprises a plurality of tiny flaky graphene and metal nanowires growing on the tiny flaky graphene, and the graphene material layer is formed by coating and assembling a plurality of graphene sheets and metal nanowire dispersion materials growing on the surfaces of the graphene sheets; d. countless mutually overlapped points among the metal nanowires coated and spread on the graphene material on the multifunctional bottom coating are welded into a whole, and all layers are fixed into a whole; d, step e, continuously coating an anti-reflection optical matching layer on the surface of the film base material treated in the step e; step e, coating films, namely laminating and covering a layer of protective film on the upper surface and the lower surface of the film substrate provided with the anti-reflection optical matching layer;

the surface modification pretreatment of the transparent film substrate is realized by adopting the following plasma jet type graphene transparent conductive film substrate pretreatment method:

treating gas such as hydrogen, oxygen, nitrogen or helium by using alternating current electromagnetic field to enable the gas to be plasmatized and sprayed to the surface of the base material; carrying out surface modification pretreatment on the film substrate, cleaning the surface, reducing the surface tension and generating polar groups on the surface; the pretreatment method is realized by adopting a gas plasma jet treatment device, the gas plasma jet treatment device comprises a horizontally arranged substrate, the substrate is positioned above one section of horizontal path of a film substrate, an ion jet torch array formed by jet torch spray pipes is vertically and downwards fixedly arranged on the lower surface of the substrate, the jet torch spray pipes are made of insulating materials, the upper ends of the jet torch spray pipes are connected with a gas source, paired electrodes are fixedly arranged at two ends of the peripheral side surface of the jet torch spray pipes along the diameter direction, and a controller connected with the electrodes is also arranged; the gas plasma jet processing apparatus includes at least one of the following features:

the method has the characteristics that: the jet torch jet pipes are arranged in multiple rows on the substrate uniformly and in a staggered manner;

the method has the following characteristics: two pairs of electrodes are arranged on the jet torch jet pipe at intervals along the vertical direction, and the connecting line direction of each pair of electrodes is vertically arranged.

2. The continuous preparation method of the roll-to-roll graphene transparent conductive film according to claim 1, wherein in the step b, the multifunctional primer coating is prepared by continuously coating a multifunctional primer coating comprising one or more of nano zinc oxide particles, nano titanium dioxide particles, nano silicon dioxide particles and nano zirconium oxide particles with a total content of 0.2-5% and a water-based acrylic resin with a total content of 3-20% on the surface of a film substrate, and drying the coating.

3. The continuous preparation method of the roll-to-roll graphene transparent conductive film according to claim 1, wherein in the step c, the graphene material layer is formed by continuously coating a graphene material layer coating, the main effective component of the graphene material layer coating comprises graphene on which metal nanowires parallel to the graphene plane are grown, and further comprises a resin as a binder.

4. The continuous roll-to-roll preparation method of the graphene transparent conductive film according to claim 1, wherein in the step e, the anti-reflection optical matching layer is formed by continuously coating an anti-reflection optical matching coating paint, and the method comprises the following steps: a. one or more of the following resins are used: tetrafluoroethylene and perfluorinated alkyl vinyl ether copolymer amorphous resin, perfluorinated ethylene propylene copolymer, and b, one or more of nano zinc oxide particles, nano titanium dioxide particles, nano silicon dioxide particles and nano zirconium oxide particles with the total content of 0.2-5%, and the fluorine-containing solvent is prepared into an anti-reflection optical matching coating for coating;

or one or more of a, modified aliphatic urethane acrylate, vinyl polysiloxane with the relative molecular weight of 20 ten thousand, mercapto polysiloxane with the relative molecular weight of 5 thousand-6 thousand and acrylic fluorosilicone polymer with the relative molecular weight of 5 ten thousand-6 ten thousand are used; b. one or more of nano zinc oxide particles, nano titanium dioxide particles, nano silicon dioxide particles and nano zirconium oxide particles with the total content of 0.2-5%; c. coating the three materials with UV (ultraviolet) for curing to obtain an anti-reflection optical matching layer;

or one or more of a, water-soluble acrylic resin, b, nano zinc oxide particles, nano titanium dioxide nanoparticles, nano silicon dioxide particles and nano zirconium oxide nanoparticles with the total content of 0.2-5 percent; the two materials are mixed with water paint and are coated and dried to obtain the anti-reflection optical matching layer.

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