Coating peeling device and coating peeling method

Abstract

To provide a coating peeling device capable of efficiently peeling a coating from a surface of a film with a coating, and preventing a peeled coating from re-adhering to the film for obtaining a base film from which a recycled film can be stably produced even if remelting is caused from a used film with a coating.SOLUTION: A coating peeling device is a device for peeling a coating from a film with a coating formed on at least one side of a base film. The device comprises: an unwinding device; a peeling mechanism that is in contact with the film with the coating and peels off the coating; a discharge nozzle that sprays air or liquid toward a vicinity of both ends of the film with the coating that are in contact with the peeling mechanism; and a winding device.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a coating peeling device and a coating peeling method that can efficiently remove a coating from the surface of a thermoplastic resin film. [Background technology]

[0002] While plastics are used in a variety of fields, they are also considered to be a cause of marine pollution, such as microplastics, making it urgent to reduce the environmental impact of plastics.

[0003] Furthermore, in recent years, advances in the Internet of Things (IoT) have led to an increase in electronic devices such as CPUs installed in computers and smartphones, and as a result, the number of multilayer ceramic capacitors (MLCCs) required to drive these electronic devices has also increased dramatically. A typical method for manufacturing MLCCs involves using a release film, which is a plastic substrate film with a release layer formed on it, as a carrier sheet, forming a ceramic green sheet layer on the release film, and peeling off the ceramic green sheet layer to obtain a ceramic green sheet. In this process, the release film from which the ceramic sheet has been peeled is discarded as waste.

[0004] That is, the rapid increase in the production volume of MLCCs in recent years has led to an increase in the amount of release film waste, which has become an environmental problem, and efforts to reuse base films are becoming more active.The components of the release layer contained in release films generally have a different composition from the components that make up the base film, from the perspective of release properties, so if a release film with a release layer is remelted as is to produce a recycled film, the components of the release layer will exist as foreign matter, making it impossible to produce a stable film.

[0005] Furthermore, even if a film can be produced, the release layer remains as a foreign substance in the resulting film, which inevitably leads to deterioration in quality due to discoloration of the film and changes in surface composition, making it impossible to regenerate the film into one with the same quality as the original substrate film.

[0006] Therefore, in order to recycle a release film as a recycled film, it is necessary to remove the components of the release layer contained in the release film to an extremely small amount of residue that does not pose a problem in terms of the quality of the recycled film.

[0007] Patent Document 1 discloses an apparatus and method for peeling a coating from a coated film, in which the coated film is immersed in a warm water bath and left in contact with the water for a certain period of time, and then the coated film is rubbed with a brush roll to peel the coating. Patent Document 2 discloses an apparatus for peeling a coating from a coated film, in which a rotating peeling blade is brought into contact with the coated surface of the coated film to peel the coating. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-363140 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-56675 Summary of the Invention [Problem to be solved by the invention]

[0009] However, in the coating peeling device and method disclosed in Patent Document 1, when the processing speed is increased, no matter how densely the brush bristles are arranged and how fast the brush rotates, when the surface is viewed from a microscopic perspective, there will always be points where the brush bristles do not come into contact with the coated film, and a small amount of the coating will remain on the recovered film after peeling as a residue. Therefore, when the recovered film is remelted and produced into a film, the quality of the recycled film will be reduced.

[0010] The coating peeling device disclosed in Patent Document 2 uses a blade-shaped peeling blade to scrape the coating from the coated film. It is sufficient if the peeled coating (hereinafter referred to as the peeled material) is dry and non-sticky so that it can easily be removed from the peeling blade. However, if the peeled material is sticky or contains moisture and is highly viscous, the peeled material may adhere to the peeling blade. The peeled material that adheres to the peeling blade accumulates on the blade and gradually flows outward across the width of the blade, adhering to the edge of the coated film being conveyed and flowing into subsequent processes. This creates a problem: the peeled material ends up contaminating the recycled film as foreign matter, causing reduced yield and quality during the production of recycled film.

[0011] Therefore, the present invention provides a coating peeling method and coating peeling device that can efficiently remove the coating from the surface of a coated film in order to obtain a base film that can be reliably remelted from used coated film to produce a recycled film. [Means for solving the problem]

[0012] The coating peeling device of the present invention, which solves the above-mentioned problems, is a device for peeling a coating from a coated film having a coating formed on at least one surface of a substrate film, the device comprising: an unwinding device that unwinds the coated film; a peeling mechanism that comes into contact with the surface of the coated film unwound from the unwinding device on which the coating is formed, and peels off the coating; a discharge nozzle for spraying air or liquid toward the vicinity of both ends of the coated film that are in contact with the peeling mechanism; and a winding device that winds up the base film from which the coating has been peeled off by the peeling mechanism.

[0013] The coating peeling device of the present invention preferably has one or more of the following features. The discharge nozzle sprays the air or the liquid toward the surface of the coated film opposite to the surface in contact with the peeling mechanism. A cleaning liquid supplying device is provided between the unwinding device and the peeling mechanism, which supplies cleaning liquid to the surface of the coating of the coated film.

[0014] The coating peeling method of the present invention, which solves the above-mentioned problems, is a method of peeling a coating from a coated film, which has a coating formed on one side of a substrate film, while transporting the coated film, comprising the steps of: A coating peeling method comprising contacting a peeling mechanism with the surface of the coated film on which the coating is formed while the film is being conveyed, and peeling the coating with the peeling mechanism while spraying air or liquid toward the vicinity of both ends of the coated film in contact with the peeling mechanism.

[0015] Furthermore, the method of peeling a coating from a coated film of the present invention preferably has one or more of the following characteristics. The air or the liquid is sprayed toward the surface of the coated film opposite to the surface that is in contact with the peeling mechanism. Before the peeling mechanism is brought into contact with the surface of the coated film on which the coating is formed while the film is being conveyed, a cleaning liquid is applied to the surface of the coating. The coating contains a water-soluble resin. The coating contains a curable silicone resin. The cleaning solution is water.

[0016] In the present invention, "blow air or liquid toward the surface opposite to the surface of the coated film that is in contact with the peeling mechanism" includes not only a blowing method in which all of the blown air or liquid hits the opposite surface, but also a blowing method in which only a portion of the blown air or liquid hits the opposite surface. [Effects of the Invention]

[0017] According to the coating peeling device and coating peeling method of the present invention, the coating can be efficiently peeled from the coated film, and the peeled material is not mixed into the recycled film. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a schematic view of a coating stripping device according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view of the peeling mechanism and the discharge nozzle of FIG. [Figure 3] 2 is a top view of the peeling mechanism and the discharge nozzle of FIG. 1. FIG. [Figure 4] 2 is a side view of the peeling mechanism and the discharge nozzle of FIG. 1. [Figure 5] FIG. 4 is a schematic view of a coating stripping device according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0019] The present inventors have conducted extensive research into methods for efficiently peeling a coating from the surface of a coated film in which a coating is formed on at least one side of a base film, without causing any peeled material to be mixed into the recycled film, and as a result have discovered the following coating peeling device and coating peeling method.

[0020] [Coating stripping device] A preferred embodiment of the coating peeling device of the present invention will be described with reference to the drawings. Note that the following description is an example of one embodiment of the present invention, and the present invention is not limited to this, and various modifications are possible within the scope of the spirit of the present invention.

[0021] 1 is a schematic diagram of a coating peeling apparatus 101 according to a first embodiment of the present invention. The coating peeling apparatus 101 includes an unwinding device 4 that unwinds a coated film 2 and a winding device 5 that winds up the base film 3 after the coating has been peeled off. Between the unwinding device 4 and the winding device 5, there are provided a drive device 9 for transporting the coated film 2, a peeling mechanism 6 for peeling the coating from the coated film 2, and a drive device 10 for transporting the base film 3 after the coating has been peeled off. The apparatus also includes a discharge nozzle 7 disposed adjacent to the peeling mechanism 6 for spraying a fluid 11, such as air or a cleaning solution, toward the coated film 2, and a splash prevention tray 8 for preventing the peeled material accumulated in the peeling mechanism 6 or the cleaning solution sprayed as fluid 11 from the discharge nozzle 7 from splashing around.

[0022] In the present invention, the drive devices 9 and 10 are preferably configured to be able to cut tension so as to stably transport the coated film 2 and the base film 3 from which the coating has been peeled off, but if tension is cut using a suction roll, part of the coating on the coated film 2 may be sucked in, which may cause problems, so a configuration in which the drive devices are nipped by a metal drive roll and a rubber roll is more preferably used. Furthermore, if a cleaning liquid is used as the fluid 11 discharged from the discharge nozzle 7, the cleaning liquid may adhere to the drive devices 9 and 10, so it is preferable to use stainless steel or one that has been surface-treated to prevent rust.

[0023] In FIG. 1 , the peeling mechanism 6 of the coating peeling device 101 is installed so as to contact the coated film 2 from below as it is being conveyed. In this case, the coated film 2 wound in a roll and set in the unwinding device 4 has a coating on the inside of the roll, and the peeling mechanism 6 comes into direct contact with the coating. The peeling mechanism 6 may be installed so as to directly contact the coating of the coated film 2, and may be installed so as to contact it from the side, obliquely, or above, rather than from below. Furthermore, in the coating peeling device 101, the peeling mechanism 6 is provided with a metal plate with a sharp tip that directly contacts the coated film 2 being conveyed. However, this is not limited thereto. Alternatively, a resin plate with a sharp tip or a thin metal plate that bends when pressed against the coated film 2 like a blade may be used. Alternatively, a rag or fabric may be pressed against the coated film 2 to wipe off the coating. For even stronger peeling, multiple peeling mechanisms 6 may be arranged in the conveyance direction. When the coated film 2 has a coating on both the front and back sides, it is sufficient to install a peeling mechanism 6 that comes into contact with each of the front and back sides, and in this case, it is preferable to install the peeling mechanism 6 at a position offset in the conveying direction via the coated film 2.

[0024] A shatter prevention tray 8 is provided around the peeling mechanism 6 to prevent the peeled material from scattering. As long as the peeled material is prevented from scattering in the surrounding area, the shatter prevention tray 8 may be arranged to surround not only the peeling mechanism 6 but also the discharge nozzle 7. In this case, the shatter prevention tray 8 has openings for the coated film 2 and the base film 3 to enter and exit. The material of the shatter prevention tray 8 is not particularly limited, but when an organic solvent or the like is used as the fluid 11 discharged from the discharge nozzle 7, it is preferable to use a chemical-resistant resin material or stainless steel material.

[0025] It is preferable that the unwinding device 4 has a mechanism that can handle either top or bottom unwinding so that the unwinding direction can be switched so that the coating of the coated film 2 wound in a roll comes into contact with the peeling mechanism 6 regardless of whether it is on the inside or outside of the roll.

[0026] The discharge nozzle 7 is a nozzle for spraying the fluid 11, and is installed close to the peeling mechanism 6 so as to discharge the fluid 11 toward the surface of the coated film 2 opposite to the side in contact with the peeling mechanism 6. Although not shown, a supply device for supplying the fluid 11 to the discharge nozzle 7 is also provided.

[0027] To check the quality of the substrate film after the coating is peeled off, an inspection machine (not shown) that detects the presence of peeled materials, coating residue, or environmental foreign matter that has adhered during the process may be installed before the winding device 5. The inspection machine may be selected according to the properties of the substrate film, and an inspection machine that uses transmitted or reflected light is preferably used. A marking device (not shown) that records the location of the coating residue or environmental foreign matter that has adhered during the process detected by the inspection machine may be installed between the inspection machine and the winding device 5. The marking method used by the marking device may be any method that can mark the location of the detected object, such as a pen, sticker, or laser. Marking the coating residue or environmental foreign matter that has adhered during the process allows the location to be removed before remelting, thereby enabling more stable production of recycled film and preventing deterioration of the recycled film's quality.

[0028] FIG. 2 is a perspective view of the peeling mechanism 6 and discharge nozzle 7 of the coating peeling device 101. Two discharge nozzles 7 are installed so that fluid 11 is discharged toward the vicinity of both widthwise ends of the coated film 2 and base film 3 passing through the peeling mechanism 6, and toward the side of the coated film 2 opposite the side in contact with the peeling mechanism 6. By discharging fluid 11 from the discharge nozzles 7, even if the peeled material generated in the peeling mechanism 6 accumulates upstream in the transport direction of the peeling mechanism 6 and flows so as to overflow toward both widthwise ends of the film, it does not flow around to the widthwise end faces of the coated film 2 or the side opposite the side in contact with the peeling mechanism 6. Although the coating peeling device 101 has two discharge nozzles 7 installed in the width direction, this is not limited thereto and may be a single discharge nozzle extending in the width direction, or three or more discharge nozzles in the width direction. Alternatively, multiple discharge nozzles may be installed in the transport direction.

[0029] The fluid 11 discharged from the discharge nozzle 7 is air or a cleaning liquid capable of dissolving the coating, but air is particularly preferred because the cleaning liquid does not get mixed into the base film 3 after the coating has been peeled off.

[0030] FIG. 3 shows the positions of the peeling mechanism 6 and the discharge nozzle 7 when the coating peeling apparatus 101 is viewed from above. The peeling mechanism 6 is installed so as to be approximately perpendicular to the film transport direction and extends in the film width direction. To explain the position of the discharge nozzle 7, the angle formed between the axis of the discharge direction of the discharge nozzle 7 and the edge face of the coated film 2 or the base film 3 is defined as α [°]. With respect to the film transport direction as the reference, α is defined as 0° when both are horizontal, +α [°] when the upper discharge nozzle 7 in FIG. 3 is positioned at an angle α [°] counterclockwise, and +α [°] when the lower discharge nozzle 7 in FIG. 3 is positioned at an angle α [°] clockwise. Note that the angle α [°] here is the angle on the paper surface of FIG. 3 and corresponds to the angle when the coating peeling apparatus 101 is viewed from above.

[0031] When using the above definition, the axis of the discharge direction of the discharge nozzle 7 is preferably 0° ≤ α ≤ +90°. When the angle α [°] exceeds +90°, the flow velocity of the fluid 11 discharged from the discharge nozzle 7 has a velocity component from the upstream side to the downstream side in the conveyance direction. That is, when discharging toward the subsequent process and the peeled matter scatters due to the discharged fluid 11, it may adhere to the base material film 3 located on the downstream side in the conveyance direction. On the other hand, when α° is less than 0°, even if it accumulates on the upstream side in the conveyance direction of the peeling mechanism 6 and adheres to the end face of the film-coated film 2 or the base material film 3, the fluid 11 cannot be directly sprayed and may flow out to the subsequent process.

[0032] The intersection point where the axis of the discharge direction of the discharge nozzle 7 intersects the end face of the film-coated film 2 or the base material film 3, and the intersection point where the ridge line where the film of the peeling mechanism 6 contacts intersects the end face of the film-coated film 2 or the base material film 3 are preferably substantially coincident, but the distance L on the film-coated film 2 or the base material film 3 between the two intersection points may be 20 mm or less. When it exceeds 20 mm, the fluid 11 cannot be efficiently sprayed onto the peeled and deposited film and may flow out to the subsequent process.

[0033] The distance r from the discharge port of the discharge nozzle 7 to the intersection point where the ridge line where the film of the peeling mechanism 6 contacts intersects the end face of the film-coated film 2 or the base material film 3 is preferably as close as possible, and it is preferably 0 mm < r ≤ 150 mm. When the distance r becomes 0 mm and the discharge nozzle 7 contacts the ridge line of the peeling mechanism 6, the discharge nozzle 7 or the peeling mechanism 6 may be damaged. Therefore, it is preferably close enough not to contact. When the distance r is installed exceeding 150 mm, the fluid 11 discharged from the discharge nozzle 7 diffuses around and loses its momentum, and the fluid 11 cannot be efficiently sprayed onto the deposited peeled matter and may flow out to the subsequent process. Here, the distance r is not the distance on the paper surface of FIG. 3, but corresponds to the actual distance including the distance in the direction perpendicular to the paper surface.

[0034] Figure 4 shows the positions of the peeling mechanism 6 and the discharge nozzle 7 when the coating peeling apparatus 101 is viewed from the side. To explain the position of the discharge nozzle 7, the angle formed between the axis of the discharge direction of the discharge nozzle 7 and the base film 3 is defined as β [°]. β° is defined as 0° when the peeling mechanism 6 and the base film 3 are positioned coaxially, with the position where they contact each other as the center, and as +β [°] when the discharge nozzle 7 is installed at a position β [°] counterclockwise relative to the base film 3 as shown in Figure 4. Note that the angle β [°] here is an angle on the paper surface of Figure 4 and corresponds to the angle when the coating peeling apparatus 101 is viewed from the side.

[0035] Using the above definition, it is preferable that the axis of the discharge direction of the discharge nozzle 7 is in the range of 0°≦β≦+90°. When β° is less than 0°, the upward component of the velocity components of the fluid 11 discharged from the discharge nozzle 7 becomes large, which may cause significant scattering of peeled material to the surroundings. When β° exceeds +90°, the component of the velocity components of the fluid 11 discharged from the discharge nozzle 7 that moves from the upstream side to the downstream side in the conveying direction becomes large. In other words, if the fluid 11 is discharged toward a subsequent process and the peeled material scatters, it may adhere to the base film 3 located downstream in the conveying direction.

[0036] The shape of the outlet of the discharge nozzle 7 may be any shape that can discharge the fluid 11, and may be selected based on the type of fluid and the required flow rate according to the properties of the peeled material. The opening may be circular, rectangular, slit-shaped, or any other shape, and multiple openings may be provided in one nozzle.

[0037] 5 is a schematic diagram of a coating peeling apparatus 201 according to a second embodiment of the present invention. The coating peeling apparatus 201 includes an unwinding device 4 that unwinds the coated film 2 and a winding device 5 that winds up the base film 3 after the coating has been peeled off. Between the unwinding device 4 and the winding device 5, there are provided a drive device 9 for transporting the coated film 2, a water tank 12 (supply device) that stores a cleaning liquid 211 for supplying the cleaning liquid 211 to the coated film 2, a peeling mechanism 6 for peeling the coating from the coated film 2, and a drive device 10 for transporting the base film 3 after the coating has been peeled off. The apparatus also includes a discharge nozzle 7 disposed adjacent to the peeling mechanism 6 for spraying a fluid 11 toward the coated film 2. A supply pump 13 for supplying the cleaning liquid 211 is connected to the water tank 12, and an adjacent drainage tank 14 is provided so that the liquid level in the water tank 12 can overflow and be drained. Because the wastewater contains peeled material generated inside the water tank 12, a filtration filter 15 is installed to separate the peeled material. The peeling mechanism 6 and discharge nozzle 7 in the coating peeling device 201 are preferably installed in the same manner as those in the coating peeling device 101. The fluid 11 discharged from the discharge nozzle 7 is air or a cleaning liquid 211. A scatter prevention tray 8 is preferably provided to collect the peeled material displaced by the sprayed fluid 11, and the scatter prevention tray 8 has an opening through which the film passes. Furthermore, the scatter prevention tray 8 is preferably installed at an angle, as shown in FIG. 5 , so that the opening through which the film passes is not located at the bottom of the scatter prevention tray 8. This prevents the peeled material and cleaning liquid from falling into the water tank 12 even if they accumulate in the scatter prevention tray 8. More preferably, a discharge outlet (not shown) is provided below the opening to constantly or periodically discharge the accumulated peeled material from the scatter prevention tray 8.

[0038] The supply device for supplying the cleaning liquid 211 to the coated film 2 is not limited to the water tank 12 shown in Figure 5, and any means may be used, such as a high-pressure nozzle or a spray nozzle, as long as the cleaning liquid 211 can be supplied uniformly over the entire coating surface of the coated film 2.

[0039] When the cleaning liquid 211 is supplied to the coated film 2, the cleaning liquid may still be attached to the film after it has passed through the peeling mechanism 6. Therefore, a drying device (not shown) may be provided between the peeling mechanism 6 and the winding device 5. The drying device may be provided before winding, and may be located either before or after the drive device 10. By providing a drying device, the substrate film 3 after the coating film wound up by the winding device 5 has been peeled away does not contain moisture, and therefore can be stably produced into a recycled film after being remelted.

[0040] In the coating peeling device 201 of Figure 5, the roll of coated film 2 set in the unwinding device 4 is wound with the coating on the outside, and the peeling mechanism 6 is configured to come into direct contact with the coating surface of the coated film 2.

[0041] [Applicable coated films] The coating peeling device, peeling method, and coating peeling film manufacturing method of the present invention are intended for coated films having a coating on the surface of a substrate film, and involve peeling and removing the coating from the substrate film. The coating may be on one or both sides of the substrate film, and is not particularly limited.

[0042] The material constituting the coating can be appropriately selected and used depending on the purpose and application of the coated film.

[0043] When imparting releasability, such as in a release film, it is preferable that the coating contains a release component as part of the coating. The release component here is a component that increases the contact angle of the coating surface with water, i.e., reduces the surface energy of the coating, and is therefore preferably, for example, a curable silicone resin compound having a dimethylsiloxane main skeleton, a compound having a long-chain alkyl group, or a compound having fluorine.

[0044] The coating may be a mixture of a release component and other different components, or a laminate of each component, depending on the required function. For example, the coating of the coated film may be an inorganic material such as a metal provided by vapor deposition, an adhesive made of an organic material such as an acrylic provided by coating, or a ceramic green sheet mainly composed of barium titanate.

[0045] Furthermore, a coated film having a coating containing a water-soluble resin that is easy to peel off and that takes into consideration environmental load, etc., may also be applicable. Among these, a water-soluble resin containing at least one of water-soluble polyester resins, polyester urethane resins, acrylic resins, ethylene ionomer resins, polyvinyl alcohol resins, polyvinylpyrrolidone resins, ethylene-vinyl alcohol resins, and starch as a main component is more preferred.

[0046] The coating containing a water-soluble resin may be a single layer containing a water-soluble resin, a laminate of two or more layers containing a water-soluble resin, or a laminate of a layer containing a water-soluble resin and a layer not containing a water-soluble resin.

[0047] [Cleaning solution] For films with coatings that are generally difficult to peel, such as those made of inorganic materials such as metals applied by vapor deposition or organic adhesives such as acrylics applied by coating, it is advisable to apply a cleaning solution to the surface of the coating of the film as a pre-peeling step. In this case, an alkaline cleaning solution is preferably used, such as an aqueous sodium hydroxide solution or an aqueous potassium hydroxide solution. These solutions may be used alone or in combination, and may contain additives such as surfactants. In other words, it is advisable to select a cleaning solution that dissolves and swells the coating and weakens the bond between the substrate film and the coating, depending on the properties of the coating to be peeled.

[0048] In particular, when peeling a coating from a coated film having a coating containing a water-soluble resin, it is preferable to use water as the cleaning liquid. The use of water can reduce the environmental impact compared to using a cleaning liquid such as an organic solvent. When water is the main component, the high surface energy of water may result in poor wettability with the coating. In such cases, additives such as surfactants or alcohols may be added to adjust the surface energy in order to improve wettability with the coating and promote dissolution and swelling of the coating.

[0049] [How to supply cleaning fluid] The cleaning solution is typically supplied by immersing the coated film in a water tank filled with the solution. In this case, the concentration of the coating components dissolved in the cleaning solution in the tank increases over time, gradually reducing the removability of the coating and causing the peeled coating to float in the tank. Therefore, it is recommended to supply fresh cleaning solution to the tank and periodically drain the cleaning solution containing dissolved coating components and the floating coating. The drained cleaning solution can be reused as a cleaning solution by removing the coating components or coating by filtration or other methods.

[0050] Other methods for supplying the cleaning solution include spraying the cleaning solution onto the surface of the coated film using a high-pressure washer, using a spray nozzle to supply the cleaning solution so that it coats the surface of the coated film, or using commonly known coating methods without using a water tank. This can reduce the amount of cleaning solution used compared to using a water tank, and can significantly reduce the environmental impact.

[0051] As another method for supplying the cleaning liquid, when water is used as the cleaning liquid, a steam washer may be used to spray steam onto the coating surface of the coated film, thereby raising the temperature of the cleaning liquid and promoting dissolution and swelling of the coating.

[0052] [Coating removal method] Next, the coating peeling method of the present invention will be described. The coating peeling method of the present invention involves directly contacting a peeling mechanism, such as a metal plate or a sharp-tipped blade, with the coating surface of the coated film being conveyed, thereby peeling the coating from the substrate film. While the coating is peeled off using the peeling mechanism, a fluid is sprayed toward the vicinity of both ends of the coated film in contact with the peeling mechanism. Even if the peeled material accumulates upstream of the peeling mechanism in the conveying direction and flows overflowing onto both ends of the coated film, the sprayed fluid can move the peeled material away from the coated film, preventing it from adhering to the end surfaces of the coated film. It is more preferable to spray the fluid toward the surface of the coated film opposite the surface that contacts the peeling mechanism. Therefore, when the substrate film wound after this peeling method is remelted and produced as a recycled film, the peeled material is not mixed in as a foreign material, allowing for more stable production of the recycled film without reducing yield and preventing a decrease in the quality of the recycled film.

[0053] The fluid sprayed toward both ends of the coated film can be selected depending on the properties of the coating to be removed. For example, when removing a coating from a ceramic green sheet primarily composed of barium titanate, the coating can be removed relatively easily by contacting the peeling mechanism. Therefore, it is preferable to select air as the fluid rather than a cleaning liquid, and the speed of the sprayed air should be adjusted so that the removed coating does not fly up to the surrounding area. This allows the coating to be removed without using unnecessary cleaning liquids such as organic solvents. Depending on the properties of the coating, it can be finely crushed upon removal. If the coating significantly flies up, spraying water in addition to air can suppress this. In this case, using water reduces the environmental impact compared to using liquids such as organic solvents.

[0054] On the other hand, when peeling a coating that is difficult to peel from a coated film, as described above, it is preferable to supply an alkaline cleaning solution to the coating surface of the coated film as a pre-peeling step. In this case, the peeled coating may be contaminated with the cleaning solution and have high viscosity, so it may be better to physically spray an alkaline cleaning solution or water rather than using air. In particular, when peeling a coating from a coated film containing a coating containing a water-soluble resin, as described above, it is preferable to use water as the cleaning solution. Even in this case, the peeled coating may be contaminated with the cleaning solution and have high viscosity, so it may be better to physically spray water rather than using air. The fluid to be sprayed may be selected from air or cleaning solution depending on the condition of the peeled coating. [Industrial Applicability]

[0055] The coated films that can be used in the coated film peeling device and peeling method of the present invention include recyclable resin films having a coating on one side of a base film, paper films, metal films, etc., but are not limited to these. [Explanation of symbols]

[0056] 2 Coated film 3. Base film 4 Unwinding device 5 Winding device 6 Peeling mechanism 7 Discharge nozzle 8. Shatterproof tray 9,10 Drive unit 11 Fluid 12 Aquarium 13 Supply pump 14 Drain tank 15 Filtration filter 101, 201 Film stripping device

Claims

1. An apparatus for peeling a coating from a coated film having a coating formed on at least one surface of a substrate film, comprising: an unwinding device that unwinds the coated film; a peeling mechanism that comes into contact with the surface of the coated film unwound from the unwinding device on which the coating is formed, and peels off the coating; a discharge nozzle that sprays air or liquid toward the vicinity of both ends of the coated film that are in contact with the peeling mechanism and toward the surface of the coated film opposite to the surface that is in contact with the peeling mechanism; a winding device that winds up the base film from which the coating has been peeled by the peeling mechanism; A coating peeling device comprising:

2. 2. The coating peeling apparatus according to claim 1, further comprising a cleaning liquid supplying device between the unwinding device and the peeling mechanism, the cleaning liquid being applied to the surface of the coating of the coated film.

3. A method for peeling a coating from a coated film, which has a coating formed on at least one surface of a substrate film, while transporting the coated film, comprising: a peeling mechanism is brought into contact with the surface of the coated film on which the coating is formed while the coated film is being conveyed, and the coating is peeled off by the peeling mechanism while air or liquid is blown toward the vicinities of both ends of the coated film in contact with the peeling mechanism and toward the surface of the coated film opposite to the surface in contact with the peeling mechanism; Film removal method.

4. 4. The coating peeling method according to claim 3, further comprising applying a cleaning liquid to the surface of the coating of the coated film being conveyed, and peeling the coating to which the cleaning liquid has been applied by the peeling mechanism.

5. 5. The coating stripping method according to claim 4, wherein the cleaning liquid is water.

6. The coating peeling method according to any one of claims 3 to 5, wherein the coating contains a water-soluble resin.

7. The coating peeling method according to any one of claims 3 to 6, wherein the coating contains a curable silicone resin.

Images