Method and device for preparing carbon nanotube transparent conductive film

Abstract

The invention discloses a method and device for preparing a carbon nanotube transparent conductive film. The method comprises the following steps: threading a flexible substrate according to a guide roller winding device and a water-cooled coating roller, installing a cathode graphite electrode and an anode graphite catalytic electrode, closing each device door, starting to evacuate, opening a process gas flow pipeline and a deposition gas pipeline, opening the gas in a post-processing chamber, connecting a low-voltage DC power supply, opening a guide roller winding device, controlling the line speed according to requirements, and monitoring the resistance change in real time through an online resistance detector. The surface resistance of the carbon nanotube transparent conductive film prepared by the method is 110-530Ω / sq, the light transmittance is 94.3%-98.1%, and the resistance uniformity is ±10%. The method is different from the floating catalytic method for preparing the carbon nanotube transparent conductive film reported before. The method has obvious advantages in terms of process control, stability, consistency, etc., and a high-quality carbon nanotube transparent conductive film can be obtained by adjusting parameters such as the distance between the anode and the cathode, the anode formula, and the air flow speed.

Description

Technical Field

[0001] The invention relates to the field of transparent conduction, and in particular to a method and a device for preparing a carbon nanotube transparent conductive film. Background Art

[0002] Transparent conductive film (TCF) is widely used in smart phones, tablet computers and other portable electronic tools. Compared with traditional ITO transparent conductive film, carbon nano-based transparent conductive film has outstanding chemical stability, good substrate adhesion, and excellent mechanical flexibility. It occupies an important position in the field of flexible display. However, due to limiting factors such as the synthesis technology and film forming technology of carbon nanomaterials, the transmittance and resistance of this type of conductive film still cannot meet industry requirements.

[0003] The preparation methods of carbon nanotube transparent conductive film (CNTs-TCF) are mainly divided into wet and dry methods. The wet process is to prepare a thin film from a carbon nanotube (CNTs) dispersion through a film-forming process such as vacuum filtration, dip coating, spray coating, spin coating, electrodeposition and inkjet printing. This process is stable and controllable, suitable for mass production, but because CNTs need to be dispersed through processes such as acid washing, sand grinding, and homogenization, their microscopic morphological structure is destroyed and excellent photoelectric performance cannot be achieved. There are currently two dry processes, one is the super array pulling method, and the other is the floating catalytic aerosol direct synthesis method. The super array pulling method utilizes the stretchability of CNTs. After the super aligned carbon nanotube array (SA-CNT) is annealed, the array direction of the CNTs changes from vertical to horizontal. Compared with the wet synthesis method, this method has high CNTs utilization rate, low cost and high film quality, but it has high quality requirements for the CNTs array, and the prepared transparent conductive film is anisotropic, and the driver chip needs to be specially designed, which increases the difficulty of subsequent application and promotion. The floating catalytic aerosol direct synthesis method is to directly deposit the CNTs aerosol generated in the vapor deposition furnace on the surface of the substrate to form a transparent conductive film.

[0004] The CNTs in the CNTs-TCF prepared by this method have a complete structure and can still maintain excellent electrical properties at a high transmittance. The aerosol direct synthesis method has a fast film preparation speed, avoids the preparation of CNTs dispersion, and improves the quality of the film, but this process parameters are complex, and the morphology and quality of CNTs are affected by factors such as the temperature of the chemical vapor deposition furnace and the flow rate of the carrier gas during the reaction. The quality is unstable, which limits its large-scale application.

[0005] Arc discharge method for synthesizing CNTs has the advantages of good crystallinity and controllable process, but CNTs prepared by arc discharge method are generally in flocculent or film form, and require secondary dispersion to obtain transparent conductive film, which seriously affects the performance. Therefore, it is urgent to develop a technology that combines the advantages of arc method to develop an efficient, controllable and continuous preparation of large-area high-quality CNTs-TCF to improve the shortcomings of existing technology. Summary of the invention

[0006] The purpose of the present invention is to provide a method and device for preparing a carbon nanotube transparent conductive film to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solution: a method and device for preparing a carbon nanotube transparent conductive film, comprising the following steps:

[0008] S1: Thread the flexible substrate according to the wiring diagram of the guide roller winding device and the water-cooled coating roller, and tighten the tension;

[0009] S2: Install the cathode graphite electrode and the anode graphite catalytic electrode;

[0010] S3: Close the doors of the unwinding room, coating room, post-processing room, winding room and other equipment, and start vacuuming;

[0011] S4: Open the process gas flow pipeline and the deposition gas pipeline;

[0012] S5: Turn on the gas in the post-processing chamber and control the gas flow rate and ethanol content;

[0013] S6: Connect low voltage DC power supply;

[0014] S7: Open the guide roller winding device, control the line speed as required, and monitor the resistance change in real time through the online resistance detector. The surface resistance of the carbon nanotube transparent conductive film prepared by this method is 110-530Ω / sq, the transmittance is 94.3%-98.1%, and the resistance uniformity is ±10%.

[0015] Preferably, in step S2, the control spacing accuracy of the cathode graphite electrode and the anode graphite catalytic electrode is ±0.1 mm, and the installation quantity is determined according to the width of the flexible substrate and is larger than the width required for coating.

[0016] Preferably, in step S3, the doors of the unwinding chamber and the winding chamber are evacuated until the vacuum degree of the coating chamber reaches less than 5.0×10-6 mbar. In step S4, the air pressure in the coating chamber is stabilized at 0.01-0.1 MPa, and the mixed gas flow velocity in the deposition gas pipeline is adjusted.

[0017] Preferably, in step S6, the current between each group of anodes and cathodes is adjusted to 50-100 A, and the specific parameters are adjusted according to the performance of the coating product.

[0018] Preferably, it comprises a flexible substrate, an unwinding chamber, a water-cooled coating roller, a plurality of coating chambers, a vacuum pump system, a low-voltage DC power supply, a post-processing chamber, a winding chamber, a guide roller winding device and an online resistance detector;

[0019] The coating chamber comprises two electrode bases, a plurality of cathode graphite electrodes, a plurality of anode graphite catalytic electrodes, a process gas flow pipeline and a deposition gas pipeline;

[0020] The vacuum pump system comprises a Roots pump, a molecular pump and a plurality of vacuum sensors.

[0021] Preferably, the flexible substrate is wound on a guide roller winding device, the guide roller winding device is arranged between the unwinding chamber, the water-cooled coating roller and the winding chamber, the water-cooled coating roller is arranged between the unwinding chamber and the winding chamber, and the flexible substrate is slidably connected to the outer wall of the water-cooled coating roller.

[0022] Preferably, the online resistance detector is arranged on one side of the water-cooled coating roller, the vacuum pump system and the low-voltage DC power supply are arranged outside the coating chamber, and the multiple coating chambers and post-processing chambers are arranged in a circular array on one side of the outer wall of the water-cooled coating roller.

[0023] Preferably, the low-voltage DC power supply is electrically connected to two electrode bases at opposite ends of the cathode graphite electrode and the anode graphite catalytic electrode, respectively, and the electrodes of the cathode graphite electrode and the anode graphite catalytic electrode are both installed on the electrode bases.

[0024] Preferably, the multiple vacuum sensors are respectively arranged in the inner cavities of multiple coating chambers, the process gas flow duct is arranged in the inner cavity of the coating chamber, the deposition gas duct is arranged directly above the distance between the cathode graphite electrode and the anode graphite catalytic electrode, and the deposition gas duct comprises multiple gas distributors and multiple microporous ceramic filter plates, and the microporous ceramic filter plates are fixed to the outer wall of the gas distributor.

[0025] Preferably, the water-cooled coating roller is made of stainless steel, the inner cavity of the water-cooled coating roller is provided with circulating condensate, the distance between the coating chamber and the water-cooled coating roller is 5 to 20 cm, preferably 10 to 15 cm, and the inner cavity of the unwinding chamber and the winding chamber is provided with a film tearing / laminating mechanism.

[0026] Technical effects and advantages of the present invention:

[0027] (1) The present invention is different from the reported floating catalytic method for preparing carbon nanotube transparent conductive film. This method has obvious advantages in process control, stability, consistency, etc., and a high-quality carbon nanotube transparent conductive film can be obtained by adjusting the parameters such as the distance between the anode and the cathode, the anode formula, and the air flow rate;

[0028] (2) The present invention belongs to a dry coating process, and the carbon nanotubes can be deposited on the surface of the flexible substrate during the arc synthesis process, and the microstructure of the carbon nanotubes will not be destroyed, thereby maintaining the high light transmittance and conductivity of the carbon nanotubes themselves;

[0029] (3) The present invention changes the disordered state of carbon nanotubes during their growth process, and promotes the carbon nanotube aerosol to adhere to the surface of the flexible substrate. The flexible substrate continuously carries away the carbon nanotube aerosol, and does not form macroscopic carbon nanotube flocs as in the traditional arc method. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0031] Figure 2 It is a schematic diagram of the overall structure of the coating chamber of the present invention.

[0032] Figure 3 It is a schematic diagram of the front view structure of the cathode graphite electrode and the anode graphite catalytic electrode of the present invention.

[0033] Figure 4 This is a schematic diagram of the top view of the deposition gas pipeline of the present invention.

[0034] Figure 5 It is a schematic diagram of the front cross-sectional structure of the deposition gas pipeline of the present invention.

[0035] In the figure: 1. Flexible substrate; 2. Unwinding chamber; 3. Water-cooled coating roller; 4. Coating chamber; 4001. Electrode base; 4002. Cathode graphite electrode; 4003. Anode graphite catalytic electrode; 4004. Process gas flow pipeline; 4005. Deposition gas pipeline; 40051. Gas distributor; 40052. Microporous ceramic filter plate; 5. Vacuum pump system; 501. Roots pump; 502. Molecular pump; 503. Vacuum sensor; 6. Low-voltage DC power supply; 7. Post-processing chamber; 8. Winding chamber; 9. Guide roller winding device; 10. Online resistance detector. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] The present invention provides a method for preparing a carbon nanotube transparent conductive film, comprising the following steps:

[0038] S1: thread the flexible substrate 1 according to the wiring diagram of the guide roller winding device 9 and the water-cooled coating roller 3, and tighten the tension;

[0039] S2: Install the cathode graphite electrode 4002 and the anode graphite catalytic electrode 4003;

[0040] S3: Close the doors of the unwinding chamber 2, the coating chamber 4, the post-processing chamber 7 and the winding chamber 8, and start vacuuming;

[0041] S4: Open the process gas flow pipeline 4004 and the deposition gas pipeline 4005;

[0042] S5: Open the gas in the post-processing chamber 7 and control the gas flow rate and ethanol content;

[0043] S6: Turn on the low voltage DC power supply 6;

[0044] S7: Open the guide roller winding device 9, control the line speed as required, and monitor the resistance change in real time through the online resistance detector 10. The surface resistance of the carbon nanotube transparent conductive film prepared by this method is 110-530Ω / sq, the transmittance without substrate is 94.3%-98.1%, and the resistance uniformity is ±10%.

[0045] In step S2, the control spacing accuracy of the cathode graphite electrode 4002 and the anode graphite catalytic electrode 4003 reaches ±0.1mm, the installation quantity is determined according to the width of the flexible substrate 1, and is greater than the width required for coating. In step S3, the doors of the unwinding chamber 2 and the winding chamber 8 and other equipment are evacuated until the vacuum degree of the coating chamber 4 reaches less than 5.0×10-6mbar. In step S4, the air pressure of the coating chamber 4 is stabilized at 0.01~0.1MPa, and the mixed gas flow velocity in the deposition gas pipeline 4005 is adjusted. In step S6, the current between each group of anodes and cathodes is adjusted to 50~100A, and the specific parameters are adjusted according to the performance of the coated product.

[0046] The present invention provides Figure 1-5The device for preparing a carbon nanotube transparent conductive film shown comprises a flexible substrate 1, an unwinding chamber 2, a water-cooled coating roller 3, a plurality of coating chambers 4, a vacuum pump system 5, a low-voltage DC power supply 6, a post-processing chamber 7, a winding chamber 8, a guide roller winding device 9 and an online resistance detector 10, wherein the coating chamber 4 comprises two electrode bases 4001, a plurality of cathode graphite electrodes 4002, a plurality of anode graphite catalytic electrodes 4003, a process gas flow pipeline 4004 and a deposition gas pipeline 4005, and the vacuum pump system 5 comprises a Roots pump 501, a molecular pump 502 and a plurality of vacuum sensors 503;

[0047] The flexible substrate 1 is wound on a guide roller winding device 9, which is arranged between the unwinding chamber 2, the water-cooled coating roller 3 and the winding chamber 8, and the water-cooled coating roller 3 is arranged between the unwinding chamber 2 and the winding chamber 8, and the flexible substrate 1 is slidably connected to the outer wall of the water-cooled coating roller 3;

[0048] An online resistance detector 10 is arranged on one side of the water-cooled coating roller 3, so as to monitor the resistance of the produced product in real time through the online resistance detector 10. A vacuum pump system 5 and a low-voltage DC power supply 6 are arranged outside the coating chamber 4. A plurality of coating chambers 4 and post-processing chambers 7 are arranged in a circular array on one side of the outer wall of the water-cooled coating roller 3, and three coating chambers 4 in the middle are in normal use, and two coating chambers 4 on the sides are used as spare coating chambers 4.

[0049] The low voltage DC power supply 6 is electrically connected to two electrode bases 4001 at opposite ends of the cathode graphite electrode 4002 and the anode graphite catalytic electrode 4003, respectively. The electrodes of the cathode graphite electrode 4002 and the anode graphite catalytic electrode 4003 are both mounted on the electrode base 4001. The diameters of the cathode graphite electrode 4002 and the anode graphite catalytic electrode 4003 are 3 to 10 mm, and the distance between the two electrodes is 1 to 3 mm. The discharge current between each group is 50 to 100 A.

[0050] The graphite electrodes of the cathode graphite electrode 4002 and the anode graphite catalytic electrode 4003 are both cylindrical structures and are formed by isostatic pressing. The anode graphite catalytic electrode 4003 is formed by mixing graphite powder and catalysts such as iron powder, nickel powder, and yttrium oxide in a specific proportion, and the purity is above 99.5%. The ratio of graphite powder to catalyst is 10 / 1 to 30 / 1. The length of the cathode graphite electrode 4002 is 5 to 10 cm, and the length of the anode graphite catalytic electrode 4003 is 10 to 20 cm. The electrode base 4001 is made of metal aluminum. The electrode base 4001 is provided with a groove that matches the graphite electrode rods of the cathode graphite electrode 4002 and the anode graphite catalytic electrode 4003, and the depth of the groove is 3 to 5 cm. The groove is provided with an internal thread, and the graphite electrode rods of the cathode graphite electrode 4002 and the anode graphite catalytic electrode 4003 are provided with an external thread, so that the graphite electrode rods and the groove form a good ohmic contact, and the distance between adjacent graphite electrode rods of the same sex is 5 to 10 mm;

[0051] The bottom of the electrode base 4001 of the anode graphite catalytic electrode 4003 is provided with an automatic propulsion system. As the reaction time increases and the electrode is consumed, it is automatically adjusted according to the set distance between the anode and the cathode and the actual distance deviation, so as to ensure that the distance error between the two electrodes is within ±0.1mm. The width of the electrode base 4001 is 550mm to 1100mm. The width of the electrode base 4001 is determined according to the width of the film to be deposited, but is not limited thereto. The number of anode and cathode graphite rods is adjusted according to the width of the electrode base 4001.

[0052] The plurality of vacuum sensors 503 are respectively arranged in the inner cavities of the plurality of coating chambers 4, so as to maintain the vacuum environment in the inner cavities of the coating chambers 4. The process gas flow pipeline 4004 is arranged in the inner cavity of the coating chamber 4, and the gas flowing in the process gas flow pipeline 4004 is generally a mixture of hydrogen and argon or helium. The deposition gas pipeline 4005 is arranged just above the distance between the cathode graphite electrode 4002 and the anode graphite catalytic electrode 4003, and the length of the deposition gas pipeline 4005 is consistent with the length of the electrode base 4001. The deposition gas pipeline 4005 includes It contains multiple gas distributors 40051 and multiple microporous ceramic filter plates 40052. The microporous ceramic filter plates 40052 are fixed to the outer wall of the gas distributor 40051. The mixed gas is evenly distributed by the gas distributor 40051 and then fully dispersed by the microporous ceramic filter plates 40052, so as to facilitate blowing the carbon nanotubes synthesized between the two electrodes to the surface of the film. The mixed gas flowing out of the microporous ceramic filter plates 40052 is a mixed gas of hydrogen and argon or helium, and the flow rate is 0.5-5 m / min, so as to prevent the formation of macroscopic carbon nanotube flocs on the surface of the flexible substrate 1.

[0053] When the device is working, the roots pump 501 is used to roughly evacuate the entire device, and then the molecular pump 502 is used to achieve high vacuum in the coating chamber 4, with a vacuum degree of 1.0 to 5.0×10-6 mbar, when the system is in production, the pressure in the coating chamber 4 is 0.01-0.1 MPa, and the process gas pipeline 4004, the deposition gas pipeline 4005 and the vacuum pump system 5 cooperate to reach the required gas pressure, and the gas is controlled by the gas mass flow controller to ensure stable flow without pulses;

[0054] At least three coating chambers 4 are arranged outside the circumference of the water-cooled coating roller 3. The spacing between the coating chamber 4 and the water-cooled coating roller 3 is 5 to 20 cm, preferably 10 to 15 cm. The water-cooled coating roller 3 is made of stainless steel and contains circulating condensate. The low temperature of -20 to 0°C can be set to ensure that the flexible substrate 1 does not deform during the coating process. The diameter of the water-cooled coating roller 3 is set according to the product production capacity requirements, and the diameter is generally 0.5 to 3 meters;

[0055] The unwinding chamber 2 and the winding chamber 8 are used to unwind and rewind the flexible substrate 1. The inner cavities of the unwinding chamber 2 and the winding chamber 8 are provided with a film tearing / laminating mechanism, which is convenient for disassembling or laminating the flexible substrate 1 on the guide roller winding device 9. The machine speed of the guide roller winding device 9 is 0.1 to 10 m / min, preferably 1 to 5 m / min. The flexible substrate 1 is one of PET, PC, TPU, PI and the like, but is not limited thereto;

[0056] The post-processing chamber 7 is arranged between the water-cooled coating roller 3 and the guide roller winding device 9, and a gas distributor 40051 is arranged inside the post-processing chamber 7 in parallel with the water-cooled coating roller 3. When working, a certain flow of helium is introduced into the gas distributor 40051, and a certain concentration of ethanol is mixed in the helium to densify the carbon nanotube film on the surface of the flexible substrate 1 and improve the adhesion between the carbon nanotube film and the flexible substrate 1. After the treated film contacts the guide roller winding device 9, problems such as film breakage and transfer will not occur. The flow rate of helium is 0.5-5m / min, and the concentration of ethanol in the carrier gas is 0.05-0.3L / m 3 A vacuum sensor 503 is also installed on the side of the winding chamber 8, so that when the vacuum degree is higher than the set value, the Roots pump 501 can start running to maintain the vacuum environment in the equipment.

[0057] The following is a detailed description of the embodiments of the present application, such as:

[0058] Embodiment 1

[0059] Step 1: Put the PET flexible substrate 1 with a width of 125um and a width of 550mm, and the light transmittance of the flexible substrate 1 is 92%, according to the wiring diagram of the guide roller winding device 9 and the water-cooled coating roller 3, and the protective film is collected by the winding of the unwinding chamber 2;

[0060] Step 2: The cathode graphite electrode 4002 has a purity of 99.5%, and the anode graphite catalytic electrode 4003 uses high-purity graphite powder and high-purity iron powder isostatic graphite electrodes, the ratio of high-purity graphite powder to high-purity iron powder is 20 / 1, and is installed on the electrode base 4001. The distance between the cathode and anode electrodes is 3mm, and the control distance accuracy is ±0.1mm. The distance between two adjacent electrodes is 5mm. 56 electrodes are installed, and the installation width is 605mm;

[0061] Step 3: Close the doors of each device and start evacuating the coating chamber 4 until the vacuum degree is 2.3×10 -6 mbar;

[0062] Step 4: Open the process gas pipeline 4004 and the deposition gas pipeline 4005, introduce a mixed gas of H2 and Ar in a ratio of 1 / 10, adjust the gas pressure of the coating chamber 4 to be stable at 0.02 MPa, and adjust the deposition gas flow rate to 2 m / min;

[0063] Step 5: Open the gas in the post-processing chamber 7 and control the gas flow rate and ethanol content. The ethanol gas content is 0.1 L / m 3 , air flow velocity is 5m / min;

[0064] Step 6: Turn on the low voltage DC power supply 6 and adjust the current between each group of anodes and cathodes to 60A;

[0065] Step 7: Turn on the guide roller winding device 9, set the water-cooled roller temperature to -20°C, set the machine speed to 2m / min, and monitor the resistance in real time through the online resistance detector 10.

[0066] The carbon nanotube transparent conductive film prepared in this embodiment has an average surface resistance of 125Ω / sq, a light transmittance of 95.2%, and a resistance uniformity of ±8%.

[0067] Embodiment 2

[0068] Step 1: 125um wide 1050mm PET, the light transmittance of the flexible substrate 1 is 92%, the flexible substrate 1 is threaded according to the wiring diagram of the guide roller winding device 9 and the water-cooled coating roller 3, and the protective film is collected by the reel of the unwinding chamber 2;

[0069] Step 2: The cathode graphite electrode 4002 has a purity of 99.5%, and the anode graphite catalytic electrode 4003 uses high-purity graphite powder and high-purity iron powder isostatic graphite electrodes, the ratio of high-purity graphite powder to high-purity iron powder is 20 / 1, and is installed on the electrode base 4001. The distance between the cathode and anode electrodes is 3mm, and the control distance accuracy is ±0.1mm. The distance between two adjacent electrodes is 5mm. 100 are installed, and the installation width is 1089mm;

[0070] Step 3: Close the doors of each device and start evacuating the coating chamber 4 until the vacuum degree is 2.3×10-6 mbar;

[0071] Step 4: Open the process gas pipeline 4004 and the deposition gas pipeline 4005, introduce a mixed gas of H2 and Ar in a ratio of 1 / 10, adjust the gas pressure of the coating chamber 4 to be stable at 0.02 MPa, and adjust the deposition gas flow rate to 2 m / min;

[0072] Step 5: Open the gas in the post-processing chamber 7 and control the gas flow rate and ethanol content. The ethanol gas content is 0.1 L / m 3 , air flow velocity is 5m / min;

[0073] Step 6: Turn on the low voltage DC power supply 6 and adjust the current between each group of anodes and cathodes to 60A;

[0074] Step 7: Turn on the guide roller winding device 9, set the water-cooled roller temperature to -20°C, set the machine speed to 2m / min, and monitor the resistance in real time through the online resistance detector 10.

[0075] The carbon nanotube transparent conductive film prepared in this embodiment has an average surface resistance of 131Ω / sq, a light transmittance of 95.3%, and a resistance uniformity of ±10%.

[0076] Embodiment 3

[0077] Step 1: 125um wide 1050mm PET, the light transmittance of the flexible substrate 1 is 92%, the flexible substrate 1 is threaded according to the wiring diagram of the guide roller winding device 9 and the water-cooled coating roller 3, and the protective film is collected by the reel of the unwinding chamber 2;

[0078] Step 2: The cathode graphite electrode 4002 has a purity of 99.5%, and the anode graphite catalytic electrode 4003 uses high-purity graphite powder and high-purity iron powder isostatic graphite electrodes, the ratio of high-purity graphite powder to high-purity iron powder is 20 / 1, and is installed on the electrode base 4001. The distance between the cathode and anode electrodes is 3mm, and the control distance accuracy is ±0.1mm. The distance between two adjacent electrodes is 5mm. 100 are installed, and the installation width is 1089mm;

[0079] Step 3: Close the doors of each device and start evacuating the coating chamber 4 until the vacuum degree is 2.3×10 -6 mbar;

[0080] Step 4: Open the process gas pipeline 4004 and the deposition gas pipeline 4005, introduce a mixed gas of H2 and Ar in a ratio of 1 / 10, adjust the gas pressure of the coating chamber 4 to be stable at 0.02 MPa, and adjust the deposition gas flow rate to 2 m / min;

[0081] Step 5: Open the gas in the post-processing chamber 7 and control the gas flow rate and ethanol content. The ethanol gas content is 0.1 L / m3 , air flow velocity is 5m / min;

[0082] Step 6: Turn on the low voltage DC power supply 6 and adjust the current between each group of anodes and cathodes to 60A;

[0083] Step 7: Turn on the guide roller winding device 9, set the water-cooled roller temperature to 0°C, set the machine speed to 2m / min, and monitor the resistance in real time through the online resistance detector 10.

[0084] The carbon nanotube transparent conductive film prepared in this embodiment has an average surface resistance of 189Ω / sq, a light transmittance of 96.4%, and a resistance uniformity of ±10%.

[0085] Embodiment 4

[0086] Step 1: 125um wide 1050mm PET, the light transmittance of the flexible substrate 1 is 92%, the flexible substrate 1 is threaded according to the wiring diagram of the guide roller winding device 9 and the water-cooled coating roller 3, and the protective film is collected by the reel of the unwinding chamber 2;

[0087] Step 2: The cathode graphite electrode 4002 has a purity of 99.5%, and the anode graphite catalytic electrode 4003 uses high-purity graphite powder and high-purity iron powder isostatic graphite electrodes, the ratio of high-purity graphite powder to high-purity iron powder is 20 / 1, and is installed on the electrode base 4001. The distance between the cathode and anode electrodes is 3mm, and the control distance accuracy is ±0.1mm. The distance between two adjacent electrodes is 5mm. 100 are installed, and the installation width is 1089mm;

[0088] Step 3: Close the doors of each device and start evacuating the coating chamber 4 until the vacuum degree is 2.3×10 -6 mbar;

[0089] Step 4: Open the process gas pipeline 4004 and the deposition gas pipeline 4005, introduce a mixed gas of H2 and Ar in a ratio of 1 / 10, adjust the gas pressure of the coating chamber 4 to be stable at 0.02MPa, and adjust the deposition gas flow rate to 4m / min;

[0090] Step 5: Open the gas in the post-processing chamber 7 and control the gas flow rate and ethanol content. The ethanol gas content is 0.1 L / m 3 , air flow velocity is 5m / min;

[0091] Step 6: Turn on the low voltage DC power supply 6 and adjust the current between each group of anodes and cathodes to 60A;

[0092] Step 7: Turn on the guide roller winding device 9, set the water-cooled roller temperature to 0°C, set the machine speed to 2m / min, and monitor the resistance in real time through the online resistance detector 10.

[0093] The carbon nanotube transparent conductive film prepared in this embodiment has an average surface resistance of 167Ω / sq, a light transmittance of 95.7%, and a resistance uniformity of ±10%.

[0094] Embodiment 5

[0095] Step 1: 125um wide 1050mm PET, the light transmittance of the flexible substrate 1 is 92%, the flexible substrate 1 is threaded according to the wiring diagram of the guide roller winding device 9 and the water-cooled coating roller 3, and the protective film is collected by the reel of the unwinding chamber 2;

[0096] Step 2: The cathode graphite electrode 4002 has a purity of 99.5%, and the anode graphite catalytic electrode 4003 uses high-purity graphite powder and high-purity iron powder isostatic graphite electrodes, the ratio of high-purity graphite powder to high-purity iron powder is 20 / 1, and is installed on the electrode base 4001. The distance between the cathode and anode electrodes is 5mm, and the control distance accuracy is ±0.1mm. The distance between two adjacent electrodes is 5mm. 100 are installed, and the installation width is 1089mm;

[0097] Step 3: Close the doors of each device and start evacuating the coating chamber 4 until the vacuum degree is 2.3×10 -6 mbar;

[0098] Step 4: Open the process gas pipeline 4004 and the deposition gas pipeline 4005, introduce a mixed gas of H2 and Ar in a ratio of 1 / 10, adjust the gas pressure of the coating chamber 4 to be stable at 0.02MPa, and adjust the deposition gas flow rate to 4m / min;

[0099] Step 5: Open the gas in the post-processing chamber 7 and control the gas flow rate and ethanol content. The ethanol gas content is 0.1 L / m 3 , air flow velocity is 5m / min;

[0100] Step 6: Turn on the low voltage DC power supply 6 and adjust the current between each group of anodes and cathodes to 60A;

[0101] Step 7: Turn on the guide roller winding device 9, set the water-cooled roller temperature to -20°C, set the machine speed to 2m / min, and monitor the resistance in real time through the online resistance detector 10.

[0102] The carbon nanotube transparent conductive film prepared in this embodiment has an average surface resistance of 257Ω / sq, a light transmittance of 97.3%, and a resistance uniformity of ±9%.

[0103] Embodiment 6

[0104] Step 1: 125um wide 1050mm PET, the light transmittance of the flexible substrate 1 is 92%, the flexible substrate 1 is threaded according to the wiring diagram of the guide roller winding device 9 and the water-cooled coating roller 3, and the protective film is collected by the reel of the unwinding chamber 2;

[0105] Step 2: The cathode graphite electrode 4002 has a purity of 99.5%, and the anode graphite catalytic electrode 4003 uses high-purity graphite powder and high-purity iron powder isostatic graphite electrodes, the ratio of high-purity graphite powder to high-purity iron powder is 20 / 1, and is installed on the electrode base 4001. The distance between the cathode and anode electrodes is 5mm, and the control distance accuracy is ±0.1mm. The distance between two adjacent electrodes is 5mm. 100 are installed, and the installation width is 1089mm;

[0106] Step 3: Close the doors of each device and start evacuating the coating chamber 4 until the vacuum degree is 2.3×10 -6 mbar;

[0107] Step 4: Open the process gas pipeline 4004 and the deposition gas pipeline 4005, introduce a mixed gas of H2 and Ar in a ratio of 1 / 10, adjust the gas pressure of the coating chamber 4 to be stable at 0.02MPa, and adjust the deposition gas flow rate to 4m / min;

[0108] Step 5: Open the gas in the post-processing chamber 7 and control the gas flow rate and ethanol content. The ethanol gas content is 0.1 L / m 3 , air flow velocity is 5m / min;

[0109] Step 6: Turn on the low voltage DC power supply 6 and adjust the current between each group of anodes and cathodes to 90A;

[0110] Step 7: Turn on the guide roller winding device 9, set the water-cooled roller temperature to -20°C, set the machine speed to 2m / min, and monitor the resistance in real time through the online resistance detector 10.

[0111] The carbon nanotube transparent conductive film prepared in this embodiment has an average surface resistance of 207Ω / sq, a light transmittance of 96.4%, and a resistance uniformity of ±8%.

[0112] Embodiment 7

[0113] Step 1: 125um wide 1050mm PET, the light transmittance of the flexible substrate 1 is 92%, the flexible substrate 1 is threaded according to the wiring diagram of the guide roller winding device 9 and the water-cooled coating roller 3, and the protective film is collected by the reel of the unwinding chamber 2;

[0114] Step 2: The cathode graphite electrode 4002 has a purity of 99.5%, and the anode graphite catalytic electrode 4003 uses high-purity graphite powder and high-purity iron powder isostatic graphite electrodes, the ratio of high-purity graphite powder to high-purity iron powder is 20 / 1, and is installed on the electrode base 4001. The distance between the cathode and anode electrodes is 5mm, and the control distance accuracy is ±0.1mm. The distance between two adjacent electrodes is 5mm. 100 are installed, and the installation width is 1089mm;

[0115] Step 3: Close the doors of each device and start evacuating the coating chamber 4 until the vacuum degree is 2.3×10 -6 mbar;

[0116] Step 4: Open the process gas pipeline 4004 and the deposition gas pipeline 4005, introduce a mixed gas of H2 and Ar in a ratio of 1 / 10, adjust the gas pressure of the coating chamber 4 to be stable at 0.02MPa, and adjust the deposition gas flow rate to 4m / min;

[0117] Step 5: Open the gas in the post-processing chamber 7 and control the gas flow rate and ethanol content. The ethanol gas content is 0.1 L / m 3 , air flow velocity is 5m / min;

[0118] Step 6: Turn on the low voltage DC power supply 6 and adjust the current between each group of anodes and cathodes to 90A;

[0119] Step 7: Turn on the guide roller winding device 9, set the water-cooled roller temperature to -20°C, set the machine speed to 5m / min, and monitor the resistance in real time through the online resistance detector 10.

[0120] The carbon nanotube transparent conductive film prepared in this embodiment has an average surface resistance of 485Ω / sq, a light transmittance of 98.4%, and a resistance uniformity of ±10%.

[0121] Comparative Example 1

[0122] The steps of comparative example 1 are consistent with those of example 2, except that the electrode spacing between the cathode and the anode is 10 mm;

[0123] The carbon nanotube transparent conductive film prepared in this comparative example has an average surface resistance of 1670Ω / sq, a light transmittance of 97.9%, and a resistance uniformity of ±15%.

[0124] Comparative Example 2

[0125] The steps of Comparative Example 2 are consistent with those of Example 2, except that the tolerance of the electrode spacing between the cathode and the anode is ±0.5 mm;

[0126] The carbon nanotube transparent conductive film prepared in this comparative example has an average surface resistance of 148Ω / sq, a light transmittance of 94.8%, and a resistance uniformity of ±32%.

[0127] Comparative Example 3

[0128] The steps of comparative example 3 are consistent with those of example 2, except that the tolerance of the distance between two electrodes of the same sex is 15 mm;

[0129] The carbon nanotube transparent conductive film prepared in this comparative example has an average surface resistance of 187Ω / sq, a light transmittance of 94.8%, and a resistance uniformity of ±59%.

[0130] Comparative Example 4

[0131] Comparative Example 4 is consistent with the steps of Example 2, except that the ethanol content in the deposition carrier gas is 0 L / m 3 ;

[0132] The carbon nanotube transparent conductive film prepared in this comparative example was adhered by the guide roller.

[0133] Comparative Example 5

[0134] Comparative Example 5 is consistent with the steps of Example 2, except that the ethanol content in the deposition carrier gas is 0.5 L / m 3 ;

[0135] The carbon nanotube transparent conductive film prepared in this comparative example has serious rainbow patterns.

[0136] Comparative Example 6

[0137] Comparative Example 6 is consistent with the steps of Example 2, except that the discharge current is 20A;

[0138] The carbon nanotube transparent conductive film prepared in this comparative example cannot measure the resistance by four-probe, no carbon nanotubes are generated, and the film is amorphous carbon.

[0139] Comparative Example 7

[0140] The steps of comparative example 7 are consistent with those of example 2, except that the discharge current is 150A;

[0141] This comparative example cannot prepare a carbon nanotube transparent conductive film, the temperature in the discharge region is too high, and the flexible substrate 1 is deformed.

[0142] Comparative Example 8

[0143] Comparative Example 8 is consistent with the steps of Example 2, except that the machine speed is 10 m / min;

[0144] The carbon nanotube transparent conductive film prepared in this comparative example has an average surface resistance of 2595Ω / sq, a light transmittance of 99.1%, and a resistance uniformity of ±20%.

[0145] Comparative Example 9

[0146] Comparative Example 8 is consistent with the steps of Example 2, except that the machine speed is 0.1 m / min;

[0147] The carbon nanotube transparent conductive film prepared in this comparative example has an average surface resistance of 57Ω / sq, a light transmittance of 85%, a resistance uniformity of ±4%, and the flexible substrate 1 is deformed.

[0148] Working principle of the present invention: The present invention has made an innovative breakthrough based on the arc discharge method, which changes the disordered state of carbon nanotubes during the growth process, and directional guides the micro-airflow of the catalyst aerosol that has a certain solubility for carbon atoms under high temperature conditions, and directional moves it toward the water-cooled coating roller 3. During the movement, carbon atoms precipitate on the surface of the catalytic particles to form carbon nanotube aerosol. At the same time, the huge temperature difference between the water-cooled coating roller 3 and the coating chamber 4 prompts the carbon nanotube aerosol to adhere to the surface of the flexible substrate 1. The flexible substrate 1 takes away the carbon nanotube aerosol continuously, and will not form macroscopic carbon nanotube flocs like the traditional arc method.

[0149] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for preparing a carbon nanotube transparent conductive film, characterized in that: The invention comprises a flexible substrate (1), an unwinding chamber (2), a water-cooled coating roller (3), a plurality of coating chambers (4), a vacuum pump system (5), a low-voltage DC power supply (6), a post-processing chamber (7), a winding chamber (8), a guide roller winding device (9) and an online resistance detector (10), wherein the flexible substrate (1) is wound on the guide roller winding device (9), the guide roller winding device (9) is arranged between the unwinding chamber (2) and the water-cooled coating roller (3), and between the water-cooled coating roller (3) and the winding chamber (8), the guide roller winding device (9) has a machine speed of 2 m / min, the water-cooled coating roller (3) is arranged between the unwinding chamber (2) and the winding chamber (8), and the guide roller winding device (9) has a machine speed of 2 m / min. The flexible substrate (1) is slidably connected to the outer wall of the water-cooled coating roller (3) between the coating chambers (8), the online resistance detector (10) is arranged on one side of the water-cooled coating roller (3), the vacuum pump system (5) and the low-voltage DC power supply (6) are arranged outside the coating chamber (4), and a plurality of the coating chambers (4) and the post-processing chambers (7) are arranged in a circular array on one side of the outer wall of the water-cooled coating roller (3), the water-cooled coating roller (3) is made of stainless steel, and the inner cavity of the water-cooled coating roller (3) is provided with circulating condensate, and the spacing between the coating chamber (4) and the water-cooled coating roller (3) is 5 to 20 cm; The coating chamber (4) comprises two electrode bases (4001), a plurality of cathode graphite electrodes (4002), a plurality of anode graphite catalytic electrodes (4003), a process gas flow pipeline (4004) and a deposition gas pipeline (4005). The low-voltage DC power supply (6) is electrically connected to the two electrode bases (4001) at opposite ends of the cathode graphite electrode (4002) and the anode graphite catalytic electrode (4003), respectively. The electrodes of the cathode graphite electrode (4002) and the anode graphite catalytic electrode (4003) are both installed on the electrode base (4001), and the spacing between the cathode and anode electrodes is 1-3 mm, and the spacing accuracy is controlled to reach ±0.1 mm. , the discharge current between each group is 50-100A, the distance between adjacent like electrodes is 5-10mm, the process gas flow pipeline (4004) is arranged in the inner cavity of the coating chamber (4), the deposition gas pipeline (4005) is arranged just above the distance between the cathode graphite electrode (4002) and the anode graphite catalytic electrode (4003), and the length of the deposition gas pipeline (4005) is consistent with the length of the electrode base (4001), and the deposition gas pipeline (4005) includes a plurality of gas distributors (40051) and a plurality of microporous ceramic filter plates (40052), and the microporous ceramic filter plates (40052) are fixed to the outer wall of the gas distributor (40051); The post-processing chamber (7) is also provided with a gas distributor (40051) parallel to the water-cooled coating roller (3). When in operation, the gas distributor (40051) introduces a certain flow of helium, in which a certain concentration of ethanol is mixed. The concentration of ethanol in the carrier gas is 0.05-0.3 L / m 3 ; The vacuum pump system (5) comprises a Roots pump (501), a molecular pump (502), and a plurality of vacuum sensors (503), wherein the plurality of vacuum sensors (503) are respectively arranged in the inner cavities of a plurality of coating chambers (4).

2. A method for preparing a carbon nanotube transparent conductive film, using the device for preparing a carbon nanotube transparent conductive film according to claim 1, characterized in that: The steps include: S1: threading the flexible substrate (1) according to the wiring diagram of the guide roller winding device (9) and the water-cooled coating roller (3), and tightening the tension; S2: Install the cathode graphite electrode (4002) and the anode graphite catalytic electrode (4003), the control spacing accuracy of the cathode graphite electrode (4002) and the anode graphite catalytic electrode (4003) reaches ±0.1mm, and the number of installations is determined according to the width of the flexible substrate (1) and is greater than the width to be coated; S3: Close the doors of the unwinding chamber (2), the coating chamber (4), the post-processing chamber (7), and the winding chamber (8), and start evacuating the chamber until the vacuum degree of the coating chamber (4) reaches less than 5.0×10 -6 mbar; S4: opening the process gas flow pipeline (4004) and the deposition gas pipeline (4005), stabilizing the gas pressure of the coating chamber (4) at 0.01-0.1 MPa, and adjusting the mixed gas flow velocity in the deposition gas pipeline (4005); S5: Open the gas in the post-processing chamber (7) and control the gas flow rate and ethanol content; S6: Turn on the low voltage DC power supply (6), and adjust the current between each group of anodes and cathodes to 50-100A. The specific parameters are adjusted according to the performance of the coating product. S7: Open the guide roller winding device (9), control the line speed according to requirements, and monitor the resistance change in real time through the online resistance detector (10). The surface resistance of the carbon nanotube transparent conductive film prepared by this method is 110~530Ω / sq, the transmittance is 94.3%~98.1%, and the resistance uniformity is ±10%.

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