Double-sided coating machine and coating method

Abstract

The invention discloses a double-sided coating machine and a coating method.The double-sided coating machine comprises a vacuum cavity, and an unwinding device used for releasing a thin film and a winding device used for winding to complete coating are arranged in the vacuum cavity; a first cooling main drum, a traction assembly and a second cooling main drum are arranged on a film feeding path of the unwinding device and the winding device, and evaporation devices are arranged below the first cooling main drum and the second cooling main drum correspondingly, so that first film layers are formed on the two side faces of a film correspondingly; magnetron sputtering devices are arranged on the peripheral sides of the first cooling main drum and the second cooling main drum so as to deposit a second film layer on the first film layer; the traction assembly is partially located on a film feeding path of the first cooling main drum and the second cooling main drum so that the to-be-coated face of the film can be turned over. By the adoption of the double-sided coating machine, double-sided coating can be rapidly achieved, and the problem that in the prior art, the coating effect is poor is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of coating equipment, and in particular to a double-sided coating machine and a coating method. Background Art

[0002] Vacuum coating technology is a process of coating the surface of materials in a vacuum environment. It is widely used in optical devices, electronic components, decorative materials, etc. It can not only improve the appearance of the material, but also enhance its wear resistance, corrosion resistance and other functional properties.

[0003] Traditional battery electrode materials mostly use copper foil or aluminum foil as current collectors. Although these materials have certain conductivity, they are insufficient in terms of battery energy density, cycle life and safety. Composite current collector materials, as a new type of electrode material, combine the advantages of multiple materials and are considered to be a substitute for traditional electrode materials. Vacuum coating technology is a major preparation method for composite current collector materials. It uses vacuum evaporation or sputtering to evaporate or deposit materials onto the surface of the substrate under vacuum conditions to form a uniform film.

[0004] However, the bonding strength between the substrate and the coating produced by the current vacuum coating technology is insufficient and is easy to fall off.

[0005] Therefore the prior art still needs to be improved and enhanced. Summary of the invention

[0006] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a double-sided coating machine and a coating method, aiming to solve the problem of poor coating effect in the prior art.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A double-sided coating machine comprises a vacuum chamber, in which an unwinding device for releasing a film and a winding device for winding up the film after coating are arranged; a first cooling main drum, a traction assembly and a second cooling main drum are arranged on the film feeding path of the unwinding device and the winding device, and an evaporation device is arranged under the first cooling main drum and the second cooling main drum so that a first film layer is formed on both sides of the film; a magnetron sputtering device is arranged on the peripheral side of the first cooling main drum and the second cooling main drum so as to deposit a second film layer on the first film layer; the traction assembly is partially located in the film feeding path of the first cooling main drum and the second cooling main drum so that the surface of the film to be coated is flipped.

[0009] Electron beam evaporation coating devices are also provided on the peripheral sides of the first cooling main drum and the second cooling main drum to form a primer film layer between the first film layer and the thin film.

[0010] The traction assembly includes a traction roller arranged on a film conveying path of the first cooling main drum and the second cooling main drum.

[0011] The diameter of the first cooling main drum and the diameter of the second cooling main drum are 2-6 times the diameter of the pulling roller.

[0012] The vacuum chamber is provided with an evaporation zone and a magnetron zone, the evaporation device is located in the evaporation zone, the magnetron sputtering device is located in the magnetron zone, and a baffle is provided between the evaporation zone and the magnetron zone to separate the two zones.

[0013] A gap is arranged between the first cooling main drum and the second cooling main drum and the baffle on one side thereof.

[0014] The vacuum degree of the magnetron region is 1.7 -1 pa-2.2 -1 pa, the vacuum degree of the evaporation zone is 1.0 -4 mpa-5.0 - 5 mpa.

[0015] The distance between the first cooling main drum and the second cooling main drum and the target material of the magnetron sputtering device on one side thereof is 50 mm-400 mm.

[0016] The evaporation device is a crucible.

[0017] A coating method using the double-sided coating machine described above comprises the following steps:

[0018] Evacuate the vacuum chamber;

[0019] The film is released by the unwinding device without stopping the machine;

[0020] The evaporation device below the first cooling main drum evaporating the first film layer on one side of the film;

[0021] Depositing a second film layer on one side of the film by a magnetron sputtering device on the peripheral side of the first cooling main drum;

[0022] The first film layer is evaporated on the other side of the film by the evaporation device under the second cooling main drum;

[0023] Depositing a second film layer on the other side of the film by a magnetron sputtering device on the peripheral side of the second cooling main drum;

[0024] The film after coating is rolled up by the rolling device without stopping the machine.

[0025] Compared with the prior art, the present invention provides a double-sided coating machine and a coating method, wherein the double-sided coating machine includes a vacuum chamber, in which a reel-out device for releasing a film and a reel-in device for reeling in the film to complete coating are arranged; a first cooling main drum, a traction assembly and a second cooling main drum are arranged on the film feeding path of the reel-out device and the film feeding path of the reel-in device, and a evaporation device is arranged under the first cooling main drum and the second cooling main drum so that a first film layer is formed on both sides of the film; a magnetron sputtering device is arranged on the circumferential side of the first cooling main drum and the second cooling main drum so as to deposit a second film layer on the first film layer; the traction assembly is partially located in the film feeding path of the first cooling main drum and the second cooling main drum so that the surface of the film to be coated is flipped. In the present application, a first film layer is first evaporated on one side of the film by an evaporation device under the first cooling main drum, and then a second film layer is deposited on the first film layer by a magnetron sputtering device on the peripheral side of the first cooling main drum. When the first film layer is still at a relatively high temperature, the high energy characteristics of magnetron sputtering are utilized to firmly fix the film layer on the film, so as to improve the problem of insufficient bonding force between the film layers in the prior art. After completing the coating on one side of the film, the film is transported by a traction assembly and guided to flip over. When the film is transported by the second cooling main drum, the first film layer is evaporated and the second film layer is deposited on the other side of the film, thereby achieving double-sided coating and improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic structural diagram of the double-sided coating machine provided by the present invention.

[0027] Figure 2 A flow chart of a coating method for a double-sided coating machine provided by the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] It should be noted that when a component is referred to as being "mounted on", "fixed on" or "disposed on" another component, it may be directly on the other component or there may be a central component at the same time. When a component is referred to as being "connected to" another component, it may be directly connected to the other component or there may be a central component at the same time.

[0030] It should also be noted that the directional terms such as left, right, up, and down in the embodiments of the present invention are merely relative concepts or are based on the normal use status of the product and should not be considered as restrictive.

[0031] Vacuum coating technology is a process of coating the surface of materials in a vacuum environment. It is widely used in optical devices, electronic components, decorative materials, etc. It can not only improve the appearance of the material, but also enhance its wear resistance, corrosion resistance and other functional properties.

[0032] Traditional battery electrode materials mostly use copper foil or aluminum foil as current collectors. Although these materials have certain conductivity, they are insufficient in terms of battery energy density, cycle life and safety. Composite current collector materials, as a new type of electrode material, combine the advantages of multiple materials and are considered to be a substitute for traditional electrode materials. Vacuum coating technology is a major preparation method for composite current collector materials. It uses vacuum evaporation or sputtering to evaporate or deposit materials onto the surface of the substrate under vacuum conditions to form a uniform film.

[0033] However, the bonding force between the substrate and the coating produced by the current vacuum coating technology is not enough and is easy to fall off. In addition, for substrates with specific requirements, double-sided coating is required. In the prior art, after the single-sided coating is completed, it is usually removed from the winding device and placed on the unwinding device to repeat the single-sided coating process to complete the coating on the other side of the substrate. Each time double-sided coating is achieved, the film material needs to be reloaded and unloaded and vacuumed. The film is easily damaged during the loading and unloading process, affecting the product quality. At the same time, the whole process will waste time, reduce production efficiency, and increase production costs.

[0034] The present invention provides a double-sided coating machine, please refer to Figure 1 , including a vacuum chamber, in which an unwinding device 1 for releasing a film and a winding device 2 for winding up the film to be coated are arranged; a first cooling main drum 31, a traction assembly and a second cooling main drum 32 are arranged on the film feeding path of the unwinding device 1 and the winding device 2, and a vapor deposition device 5 is arranged below the first cooling main drum 31 and the second cooling main drum 32, so that a first film layer is formed on both sides of the film; a magnetron sputtering device 6 is arranged on the peripheral side of the first cooling main drum 31 and the second cooling main drum 32, so as to deposit a second film layer on the first film layer; the traction assembly is partially located on the film feeding path of the first cooling main drum 31 and the second cooling main drum 32, so that the surface of the film to be coated is turned over. The double-sided coating machine of the present application can quickly realize double-sided coating, improving the problem of poor coating effect in the prior art.

[0035] In the present application, the first film layer is firstly evaporated on one side of the film by the evaporation device 5 under the first cooling main drum 31, and then the second film layer is deposited on the first film layer by the magnetron sputtering device 6 on the side of the first cooling main drum 31. When the first film layer is still at a relatively high temperature, the two film layers are firmly fixed on the film by using the high energy characteristics of magnetron sputtering, so as to improve the problem of insufficient bonding force between the film and the film layer in the prior art; after the film coating is completed on one side of the film, the film is transported and guided to flip by the traction component, and the first film layer is evaporated and the second film layer is deposited on the other side of the film when the second cooling main drum 32 transports the film, thereby achieving double-sided coating and improving production efficiency. It should be noted that the film in the present application is the substrate to be coated. The film in the present application is usually a PP film, a PET film, a PI film or other insulating and non-conductive film. During the coating process, the film is cooled by the first cooling main drum 31 and the second cooling main drum 32, which can ensure that the film is not burned through by the high-temperature metal material to form pinholes, and can also prevent the film from becoming brittle at high temperatures.

[0036] Furthermore, an electron beam evaporation coating device 7 is also provided on the circumference of the first cooling main drum 31 and the second cooling main drum 32 to form a primer film layer between the first film layer and the film. In the present application, the electron beam evaporation coating device 7 is used to evaporate a primer film layer on the film, that is, firstly, the primer film layer is formed on the film by the electron beam evaporation coating device 7, and then the evaporation device 5 heats the material to be evaporated to deposit the first film layer on the primer film layer, so as to improve the bonding force between the first film layer and the film, and help to improve the overall performance of the film. In the present application, the evaporation device 5 is a crucible evaporation. In order to improve the evaporation efficiency, more materials are placed inside the crucible during evaporation, so the film is subjected to a higher temperature when the first film layer is evaporated. By forming a thin primer film layer on the film in advance by the electron beam evaporation coating device 7, the high temperature resistance of the film can be improved, and the film can be prevented from becoming brittle or burning due to high temperature during the evaporation of the first film layer. In the present application, the metal material contained in the crucible and the metal target material sputtered by magnetron sputtering can be the same or different; preferably, the metal target material of magnetron sputtering is different from the metal material evaporated in the crucible, especially when the material evaporated in the crucible is copper, the first film layer and the second film layer are prone to adhesion.

[0037] Electron beam evaporation is a method of using an electron beam to directly heat the evaporated material under vacuum conditions, vaporize the evaporated material and transport it to the substrate, and condense it on the substrate to form a thin film. Evaporation is a method of vaporizing the coating material by heating it under vacuum conditions, and then depositing particles on the surface of the substrate to form a film layer. In the present application, the electron beam evaporation coating device 7 adjusts the energy and focus of the electron beam, etc., so that the film layer has high purity and the thickness can be controlled more accurately. Therefore, before evaporating the first film layer on the film, a primer film layer is first formed on the film, and the primer film layer fills the tiny defects on the surface of the film, such as scratches, pits, etc., so that the surface of the film is smoother. Since the first film layer is on the film to thicken, a large amount of material to be evaporated will be deposited on the film when the first film layer is formed. If the surface of the film is uneven, the film will be heated unevenly during the evaporation process, which will cause the film to deform.

[0038] Furthermore, the traction assembly includes a traction roller 41 arranged on the film feeding path of the first cooling main drum 31 and the second cooling main drum 32. Two traction rollers 41 are arranged on the film feeding path of the first cooling main drum 31 and the second cooling main drum 32. By accurately controlling the rotation speed of the traction rollers 41, the coating speed can be adjusted to avoid the situation where the film is conveyed too fast or too slow, resulting in poor coating effect; the two traction rollers 41 also play a guiding and positioning role, ensuring that the film can be conveyed according to the predetermined path and position during the coating process. At the same time, after the film is coated on one side, the two traction rollers 41 turn over the surface of the film to be coated during the conveying process of the film, so as to facilitate coating on the other side of the film. A traction roller 41 is also arranged on the film feeding path of the second cooling main drum 32 and the winding device 2 to pull the coated film and smoothly wind it on the winding device 2.

[0039] In the present application, since the film is coated by evaporation and magnetron sputtering successively when passing through the first cooling main drum 31 and the second cooling main drum 32, in order to avoid interference between the two coating methods, the diameter of the first cooling main drum 31 and the diameter of the second cooling main drum 32 are 2-6 times the diameter of the traction roller 41. In the present application, the first cooling main drum 31 and the second cooling main drum 32 are used to support the film during the film conveying process, and the electron beam evaporation coating device 7 is used to form a base film layer on the film, and the evaporation device 5 evaporates the first film layer on the base film layer, and the magnetron sputtering device 6 is used to deposit the second film layer on the first film layer, so that double-sided continuous coating can be achieved in the vacuum chamber, which greatly reduces the time of double-sided coating, improves production efficiency, reduces the number of vacuum breaks, and avoids film oxidation.

[0040] Furthermore, a vapor deposition area and a magnetron area are provided in the vacuum chamber, the vapor deposition device 5 is located in the vapor deposition area, the magnetron sputtering device 6 is located in the magnetron area, and a baffle 8 is provided between the vapor deposition area and the magnetron area to separate the two areas. In the present application, the magnetron sputtering device 6 requires the participation of an inert gas (such as argon) during the coating process. In order to avoid the influence of the inert gas on the crucible during evaporation, the vapor deposition area and the magnetron area are separated by a baffle 8 to ensure the coating effect.

[0041] Furthermore, the first cooling drum 31 and the second cooling drum 32 are both provided with a gap in the vertical direction with the baffle 8 on their respective sides (i.e., there is a height difference between the lower ends of the two cooling drums and the baffles on their respective sides in the vertical direction), so that the film can pass between the cooling drum and the baffle. The gap in the vertical direction between the first cooling drum 31 and the baffle 8 on its respective side is 3mm-10mm, and the gap in the vertical direction between the second cooling drum 32 and the baffle 8 on its respective side is also 3mm-10mm; preferably, the gap in the vertical direction (i.e., the height difference) between the two cooling drums and the baffle 8 on their respective sides is the same, which helps to ensure the uniformity of the first film layer on both sides of the film; the baffle 8 is provided with an opening of adjustable size, and the material to be evaporated after being evaporated by the evaporation device 5 passes through the opening and is deposited on the film. By adjusting the size of the opening, more material to be evaporated passes through the opening and is deposited on the film, thereby ensuring the thickness of the film layer on the film.

[0042] Furthermore, the vacuum degree of the magnetron region is 1.7 -1 pa-2.2 -1 pa, the vacuum degree of the evaporation zone is 1.0 - 4 mpa-5.0 -5 mpa, that is, the vacuum degree of the magnetron area is greater than the vacuum degree of the evaporation area, which is beneficial to improving the bonding strength between the film layer and the thin film.

[0043] Furthermore, the distance between the first cooling main drum 31 and the second cooling main drum 32 and the target material of the magnetron sputtering device 6 on the side where they are located is 50mm-400mm. Specifically, when the target material of the magnetron sputtering device 6 is a rotating target material, the distance between the first cooling main drum 31 and the second cooling main drum 32 and the target material of the magnetron sputtering device 6 on the side where they are located is 50mm-100mm; when the target material of the magnetron sputtering device 6 is a planar target material, the distance between the first cooling main drum 31 and the second cooling main drum 32 and the target material of the magnetron sputtering device 6 on the side where they are located is 200mm-400mm; according to different target material selections, limiting the distance between the cooling main drum and the target material can minimize the coating distance and improve the bonding strength between the film layer and the thin film. It should be noted that the structure and working principle of the rotating target material and the planar target material belong to the prior art and will not be elaborated here.

[0044] Furthermore, the evaporation device 5 is a crucible. In the present application, a metal material to be evaporated, such as aluminum metal or copper metal, is placed in the crucible. The metal material will melt after reaching its melting point at high temperature. When the temperature continues to rise, the metal material will evaporate and deposit on the film conveyed by the first cooling main drum 31 and the second cooling main drum 32, thereby forming a film layer. By using a crucible as the evaporation device 5, a large amount of metal material can be placed in the crucible at one time, and a thicker film layer can be formed on the film at one time under high temperature conditions.

[0045] The present application also provides a coating method using the double-sided coating machine, see Figure 2 , including the following steps:

[0046] Evacuate the vacuum chamber;

[0047] The film is released by the unwinding device without stopping the machine;

[0048] The evaporation device below the first cooling main drum evaporating the first film layer on one side of the film;

[0049] Depositing a second film layer on one side of the film by a magnetron sputtering device on the peripheral side of the first cooling main drum;

[0050] The first film layer is evaporated on the other side of the film by the evaporation device under the second cooling main drum;

[0051] Depositing a second film layer on the other side of the film by a magnetron sputtering device on the peripheral side of the second cooling main drum;

[0052] The film after coating is reeled up by the reeling device without stopping. The coating method of the present application can quickly realize double-sided coating, and the primer film layer, the first film layer and the second film layer are coated on both sides of the film, so that the film and the film layer are more tightly combined, which is conducive to improving the stability and durability of the film.

[0053] In summary, the present invention provides a double-sided coating machine and a coating method, wherein the double-sided coating machine includes a vacuum chamber, in which a reel-out device for releasing a film and a reel-in device for reeling in the film to complete the coating are arranged; a first cooling main drum, a traction assembly and a second cooling main drum are arranged on the film feeding path of the reel-out device and the film feeding path of the reel-in device, and a evaporation device is arranged under the first cooling main drum and the second cooling main drum so that a first film layer is formed on both sides of the film; a magnetron sputtering device is arranged on the circumferential side of the first cooling main drum and the second cooling main drum so as to deposit a second film layer on the first film layer; the traction assembly is partially located in the film feeding path of the first cooling main drum and the second cooling main drum so that the surface of the film to be coated is flipped. In the present application, a first film layer is first evaporated on one side of the film by an evaporation device under the first cooling main drum, and then a second film layer is deposited on the first film layer by a magnetron sputtering device on the peripheral side of the first cooling main drum. When the first film layer is still at a relatively high temperature, the high energy characteristics of magnetron sputtering are utilized to firmly fix the film layer on the film, so as to improve the problem of insufficient bonding force between the film layers in the prior art. After completing the coating on one side of the film, the film is transported by a traction assembly and guided to flip over. When the film is transported by the second cooling main drum, the first film layer is evaporated and the second film layer is deposited on the other side of the film, thereby achieving double-sided coating and improving production efficiency.

[0054] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention, and all these changes or substitutions should fall within the protection scope of the claims attached to the present invention.

Claims

1. A double-sided coating machine, characterized in that: It comprises a vacuum chamber, in which an unwinding device for releasing a film and a winding device for winding up to complete coating are arranged; a first cooling main drum, a traction assembly and a second cooling main drum are arranged on the film feeding path of the unwinding device and the winding device, and an evaporation device is arranged under the first cooling main drum and the second cooling main drum so that a first film layer is formed on both side surfaces of the film; a magnetron sputtering device is arranged on the peripheral side of the first cooling main drum and the second cooling main drum so as to deposit a second film layer on the first film layer; the traction assembly is partially located in the film feeding path of the first cooling main drum and the second cooling main drum so that the surface of the film to be coated is flipped.

2. The double-sided coating machine according to claim 1, characterized in that: Electron beam evaporation coating devices are also provided on the peripheral sides of the first cooling main drum and the second cooling main drum to form a primer film layer between the first film layer and the thin film.

3. The double-sided coating machine according to claim 1, characterized in that: The traction assembly includes a traction roller arranged on a film conveying path of the first cooling main drum and the second cooling main drum.

4. The double-sided coating machine according to claim 3, characterized in that: The diameter of the first cooling main drum and the diameter of the second cooling main drum are 2-6 times the diameter of the pulling roller.

5. The double-sided coating machine according to claim 1, characterized in that: The vacuum chamber is provided with an evaporation zone and a magnetron zone, the evaporation device is located in the evaporation zone, the magnetron sputtering device is located in the magnetron zone, and a baffle is provided between the evaporation zone and the magnetron zone to separate the two zones.

6. The double-sided coating machine according to claim 5, characterized in that: A gap is arranged between the first cooling main drum and the second cooling main drum and the baffle on one side thereof.

7. The double-sided coating machine according to claim 5, characterized in that: The vacuum degree of the magnetron region is 1.7 -1 pa-2.2 -1 pa, the vacuum degree of the evaporation zone is 1.0 -4 mpa-5.0 -5 mpa.

8. The double-sided coating machine according to claim 1, characterized in that: The distance between the first cooling main drum and the second cooling main drum and the target material of the magnetron sputtering device on one side thereof is 50 mm-400 mm.

9. The double-sided coating machine according to claim 1, characterized in that: The evaporation device is a crucible.

10. A coating method using the double-sided coating machine according to any one of claims 1 to 9, characterized in that: The steps include: Evacuate the vacuum chamber; The film is released by the unwinding device without stopping the machine; The evaporation device below the first cooling main drum evaporating the first film layer on one side of the film; Depositing a second film layer on one side of the film by a magnetron sputtering device on the peripheral side of the first cooling main drum; The first film layer is evaporated on the other side of the film by the evaporation device under the second cooling main drum; Depositing a second film layer on the other side of the film by a magnetron sputtering device on the peripheral side of the second cooling main drum; The film after coating is rolled up by the rolling device without stopping the machine.

Images