Coating film peeling method and coating film peeling device

Abstract

The present invention provides a coating film peeling method and a coating film peeling device with which it is possible to efficiently and reliably peel a coating film from a base film having a coating film, using a washing solution. A method for peeling a coating film from a base film having a coating film according to the present invention is for peeling a coating film from a base film having a coating film which has a coating film containing a water-soluble resin, and is characterized in that a washing solution is applied in a range of 3-650 mL / m2 to the surface of the coating film, then, while bringing a peeling member into direct contact with the coating film surface of the base film having a coating film and while making the angle formed by the base film via the peeling member be in the range of 20-150° and applying tension in the range of 10-1000 N / m in at least one longitudinal direction of the base film, moving the base film in the longitudinal direction of the base film relative to the peeling member to peel away the coating layer containing the washing solution.

Description

Coating stripping method and coating stripping device

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

[0002] While plastics are used in a variety of fields, they are also considered a cause of marine pollution, such as microplastics, making it urgent to reduce the environmental impact of plastics. Furthermore, with the recent advancement of the Internet of Things (IoT), the number of electronic devices, such as CPUs, installed in computers and smartphones has increased, and 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 has a release layer formed on a plastic substrate film, as a carrier sheet, forming a ceramic green sheet layer on the release film, and peeling 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.

[0003] In other words, the increase in release film waste due to the rapid increase in the number of MLCCs in recent years has become an environmental problem, and efforts to reuse plastic substrate films have been active.The components of the release layer contained in the release film generally have a different composition from the components that make up the substrate 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.

[0004] Patent Document 1 discloses a method for removing a release component from a release film, in which a release film having a water-soluble resin layer formed between the base film and the release layer is used, and the release film is immersed in a hot water bath for 2 seconds or more, and then the release layer is peeled off by rubbing the surface of the release film with a brush roll. Patent Document 2 discloses a method for removing a coating from a base film having a coating formed by coating, and discloses an apparatus that includes a dissolution tank containing an organic solvent, and a scraper that can be brought into contact with the coating surface is installed at the bottom of the dissolution tank, and that dissolves and removes the coating from a base film having a coating that is being transported.

[0005] JP 2004-363140 A JP 2021-146682 A

[0006] However, the coating peeling method disclosed in Patent Document 1 has the problem that, because the water-soluble resin layer dissolves in the hot water tank, the resin concentration in the hot water increases over the course of treatment, making it impossible to continue to demonstrate the initial peeling ability. Even if a method of increasing the amount of water supplied is adopted to suppress the increase in resin concentration, the amount of wastewater increases along with the amount of water supplied, resulting in problems such as a significant increase in cleaning costs and a heavy environmental load.

[0007] Furthermore, the coating peeling method disclosed in Patent Document 2 uses an organic solvent to dissolve and remove the coating, and as with Patent Document 1, a large amount of organic solvent is required to continue to exhibit the initial peeling ability, resulting in a significant environmental impact. Furthermore, the device is configured so that a scraper installed at the bottom of the dissolution tank directly contacts the coating surface of the substrate film carrying the coating being transported to scrape off the coating. However, because the substrate film is transported through the liquid, when the scraper scrapes off the coating, organic solvent is likely to be interposed between the coating surface and the scraper, which may result in insufficient scraping ability. One conceivable way to improve the scraping ability would be to use the scraper to make the angle between the film surfaces on the upstream and downstream sides of the substrate film transport direction acute. However, this would require a deeper dissolution tank, which would increase the volume of the dissolution tank and further increase the amount of organic solvent used, further exacerbating the environmental impact.

[0008] Therefore, the present invention provides a coating peeling method and coating peeling device that can efficiently and reliably peel off a coating from the surface of a substrate film having a coating containing a water-soluble resin on one side thereof by using a small amount of cleaning liquid to dissolve the water-soluble resin, in order to obtain a substrate film that can be reliably used to produce a recycled film even when remelted from a substrate film having a coating after use.

[0009] [1] The coating peeling method of the present invention, which solves the above-mentioned problems, is a method for peeling a coating containing a water-soluble resin from a substrate film having the coating on at least one side thereof, the method comprising: applying a cleaning solution containing water as a main component to the coating, the cleaning solution being a solution containing a water-soluble resin on a surface area of ​​1 m ２ A peeling member is brought into contact with the surface of the coating to which the cleaning solution has been applied, and the base film is moved in the longitudinal direction of the base film relative to the peeling member while setting the angle formed by the base film via the peeling member to be in the range of 20 to 150° and applying tension in the range of 10 to 1000 N / m in at least one direction of the longitudinal direction of the base film, thereby peeling the coating from the base film.

[0010] [2] In the coating peeling method of [1] above, the length in the longitudinal direction of the base film within the range where the peeling member is in contact with the surface of the coating is defined as a contact length L [m], a plane passing through the center position of the contact length and perpendicular to the surface of the peeling member is defined as a vertical plane, the side where the base film approaches the peeling member relatively is defined as an upstream side, and the side where the base film moves away from the peeling member relatively is defined as a downstream side, and the contact length L is 1×10 －５ ~1 x 10 －３ m, and the angle (acute angle) θ between the vertical plane and the base film located upstream of the vertical plane １ [°], the angle (acute angle) θ between the vertical plane and the base film downstream of the vertical plane ２ [°], tension T applied to the base film upstream of the vertical plane １ [N / m], and the tension T applied to the base film downstream of the vertical plane ２It is preferable that the tension [N / m] satisfies the following formula (1): Formula (1): 1.0 × 10 ６ ≦{T １ × cos(θ １ ) + T ２ × cos(θ ２ ) / L≦2.4×10 ８

[0011] [3] In the coating peeling method of [1] or [2] above, it is preferable that, of the two surfaces constituting the peeling member that sandwich the ridge line where the peeling member begins to come into contact with the surface of the coating, the surface facing the base film before coming into contact with the ridge line forms an angle of 5° or more with the base film before coming into contact with the ridge line. [4] In any of the coating peeling methods of [1] to [3] above, it is preferable that the coating contains a curable silicone resin.

[0012] [5] A coating peeling device of the present invention that solves the above-mentioned problems is a device for peeling a coating containing a water-soluble resin from a substrate film having the coating on at least one surface thereof, the device comprising: a cleaning liquid application mechanism for applying a cleaning liquid to the coating; a peeling member for peeling the coating to which the cleaning liquid has been applied from the substrate film; a drive device for moving the substrate film relative to the peeling member in the longitudinal direction of the substrate film; and a tension application mechanism for applying tension to the substrate film in at least one direction in the longitudinal direction, the cleaning liquid application mechanism applying the cleaning liquid to a surface of 1 m of the coating. ２ The peeling member is arranged so that it comes into contact with the surface of the coating to which the cleaning liquid has been applied and so that the angle formed between the substrate films via the peeling member is in the range of 20 to 150°, and the tensioning mechanism is adjusted so as to apply a tension in the range of 10 to 1000 N / m.

[0013] [6] The coating peeling device according to [5] above, wherein the length L in the longitudinal direction of the base film of the area where the peeling member contacts the surface of the coating is 1×10 －５ ~1 x 10 －３It is preferable that the thickness is in the range of m. [7] The coating peeling device of [5] or [6] above is preferably equipped with an unwinding device for unwinding the substrate film having the coating wound in a roll, and a winding device for winding up the substrate film from which the coating has been peeled. Note that the substrate film before contact with the peeling member is called a "substrate film having a coating," and the substrate film after contact with the peeling member is called a "substrate film from which the coating has been peeled," but in the coating peeling methods of [1] to [4] above and the coating peeling devices of [5] to [7] above, no particular distinction is made and both are referred to as a "substrate film."

[0014] According to the coating peeling method and coating peeling device of the present invention, a coating containing a water-soluble resin can be efficiently and reliably peeled off from a substrate film having a coating on one side thereof using a small amount of cleaning liquid.

[0015] 1 is a schematic diagram of a stripping device according to one embodiment of the present invention; FIG. 2 is a schematic diagram of a stripping member according to a first embodiment of the stripping device of the present invention; FIG. 3 is a schematic diagram of a stripping member according to a second embodiment of the stripping device of the present invention; FIG. 4 is a schematic diagram of a stripping member according to a third embodiment of the stripping device of the present invention; FIG. 5 is a graph showing the results of stripping a coating under the conditions of Example 1; FIG. 6 is a graph showing the results of stripping a coating under the conditions of Example 2; and FIG. 7 is a graph showing the results of stripping a coating under the conditions of Example 3.

[0016] The present inventors have conducted extensive research into a method for efficiently and reliably peeling a coating from the surface of a coated film having a coating containing a water-soluble resin on one side of a substrate film using a very small amount of cleaning liquid, and as a result have discovered the following coating peeling method and coating peeling device.

[0017] [Substrate Film Having a Coating to Be Targeted] The method of peeling a coating from a substrate film having a coating of the present invention is a method for peeling and removing a coating from a substrate film having a coating containing a water-soluble resin on at least one side of the substrate film by cleaning the coating. The coating may be present on one or both sides of the substrate film, and is not particularly limited.

[0018] The target substrate films having a coating film may include substrate films having a coating film containing other water-soluble resins in addition to coating films containing water-soluble resins that take into consideration environmental load, etc. Among these, more preferred water-soluble resins are those 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 the main component.

[0019] 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.

[0020] In addition, a coated release film containing a release component in addition to the water-soluble resin as part of the coating is particularly preferred, as it can efficiently exhibit the effect of peeling off the coating. The release component here refers to a component that increases the contact angle of the coating surface with water, i.e., reduces the surface energy of the coating. Examples include curable silicone resins, such as thermosetting silicone resin compounds with dimethylsiloxane as the main skeleton, UV-curable silicone resin compounds in which a photopolymerization initiator is blended with an organopolysiloxane containing an acryloyl group or a methacryloyl group and cured by irradiating it with UV light, as well as compounds with long-chain alkyl groups and compounds containing fluorine. The coating may be a mixture of the water-soluble resin and the release component, or the respective layers may be laminated. In the case of a laminated coating, it is preferable to form a layer containing the water-soluble resin directly on the substrate film, and then a layer containing the release component on the outermost surface. It is particularly preferable to use a thermosetting silicone resin compound with dimethylsiloxane as the main skeleton, which has high water permeability, as the release component.

[0021] [Method for Peeling a Coating from a Substrate Film Having a Coating] The coating peeling method of the present invention involves applying a cleaning solution containing water as a main component to the surface of a substrate film having a coating containing the above-mentioned water-soluble resin on at least one side thereof, in a range of 1 m2 of the surface area of ​​the coating. ２The method applies a cleaning solution in an amount of 3 to 650 ml per unit area, brings a peeling member into contact with the surface of the coating to which the cleaning solution has been applied, and moves the base film in its longitudinal direction relative to the peeling member while setting the angle formed by the base film via the peeling member to be in the range of 20 to 150° and applying tension in the range of 10 to 1000 N / m in at least one direction along the longitudinal direction of the base film, thereby removing the coating from the base film having the coating thereon.

[0022] The method for applying the cleaning liquid to the coating surface in the coating peeling method of the present invention may be any method. For example, the cleaning liquid may be applied in the form of droplets using a spray nozzle, or a high-pressure or high-temperature cleaning liquid may be applied using a high-pressure washer or steam generator. The amount of cleaning liquid applied is preferably adjusted appropriately depending on the properties and thickness of the coating to be peeled, and is preferably appropriately controlled by the method of applying the cleaning liquid. For example, the cleaning liquid may be controlled by sending it with a metering pump, a flow meter may be installed in the flow path through which the cleaning liquid is sent, or the cleaning liquid applied to the coating surface may be recovered and its mass may be measured. Alternatively, if the water-soluble resin contains a cleaning liquid and mass measurement is difficult, the substrate film with the coating, the applied cleaning liquid, and the peeled coating may all be collected, and the amount of cleaning liquid applied may be calculated.

[0023] As a result of extensive research by the present inventors, it was found that the thickness of the coating containing the water-soluble resin was 20×10 －６ When the thickness is between 1.0 mm and 1.0 mm, the amount of cleaning solution applied is ２ It was confirmed that the coating peeling effect could be obtained by using 3 ml or more per 1 m of surface area of ​​the coating. ２ It has been confirmed that if the amount is less than 3 ml per unit area, the coating peeling effect may be reduced, and particularly when the humidity of the surrounding environment is low, the cleaning solution may dry out before it can dissolve or swell the coating containing the water-soluble resin, making it impossible to achieve the coating peeling effect. On the other hand, the greater the amount of cleaning solution applied, the more reliably the coating containing the water-soluble resin can be dissolved or swelled, improving the coating peeling effect. In particular, even when the thickness of the coating containing the water-soluble resin is 1.0 mm, the coating surface area of ​​1 m ２It was confirmed that the coating peeling effect could be obtained by applying 650 ml of cleaning solution per unit time to the coating surface.

[0024] The cleaning solution used in the coating peeling method of the present invention can be any solvent that can dissolve the water-soluble resin, but water is preferred to reduce the environmental impact. Furthermore, by adding a surfactant or the like to a water-based cleaning solution, the wettability of the cleaning solution with the coating surface can be improved, making it easier for the cleaning solution to spread throughout the entire coating.

[0025] The peeling member in the coating peeling method of the present invention may be, but is not limited to, a scraper, fabric, metal plate, or rotating brush roll. Any means may be used as long as it can directly contact the coated substrate film and physically peel off the coating. The peeling member is preferably pressed into direct contact with the coated surface of the substrate film. The substrate film is bent or curved by the peeling member, and while maintaining this state, the substrate film is moved relative to the peeling member in its longitudinal direction, thereby peeling the coating off the substrate film. The substrate film in the bent or curved state is preferably angled at 20 to 150° by the peeling member, and tensioned in at least one direction along the longitudinal direction by 10 to 1000 N / m. This allows the peeling member to be pressed firmly against the coating surface of the substrate film, thereby enabling efficient and reliable peeling of the coating dissolved or swollen by the cleaning solution. Therefore, the smaller the area of ​​contact of the peeling member with the substrate film having the coating, the more strongly the peeling member can be pressed locally against the coating surface of the substrate film, which is preferable, and of the peeling members exemplified above, scrapers and the corners of metal plates are preferably used.

[0026] When the angle formed by the base film via the peeling member is less than 20°, the space for installing the peeling member becomes very narrow, which is not practical. On the other hand, when the angle is greater than 150°, the force pressing the peeling member against the coating surface of the base film is weakened, but it was confirmed that peeling is possible for some coating properties that are easy to peel. However, it was confirmed that when the base film and the peeling member are moved relatively in the longitudinal direction of the base film, tension fluctuations occur or the peeling speed is increased, and air is easily entrained between the base film and the peeling member, and part of the coating cannot be peeled off and slips through, remaining on the base film.

[0027] It has been confirmed that the coating peeling effect is achieved by applying a tension of 10 N / m or more in at least one direction of the longitudinal direction of the substrate film. When the substrate film is conveyed with an applied tension of less than 10 N / m, the low tension makes stable conveyance impossible, and the tension fluctuates greatly or meanders during conveyance, making it impossible to peel the coating. On the other hand, when a tension of more than 1000 N / m is applied, the substrate film is pulled strongly in one direction, causing multiple corrugations in the width direction of the substrate film along the longitudinal direction, and some of these corrugations become creases at the points where they come into contact with the peeling member, making it impossible to peel the coating at the creases.

[0028] In the coating peeling method of the present invention, the substrate film having the coating of the preferred embodiment described above is moved relative to the peeling member in its longitudinal direction to peel the coating from the substrate film. Any means may be used to move the substrate film relative to the peeling member. The peeling member may be fixed and only the substrate film may be transported, or the peeling member may be moved relative to the stationary substrate film. Alternatively, both the peeling member and the substrate film may move, either in the same direction or in different directions. When transporting the substrate film, it is preferable to maintain a constant tension on the substrate film. It is also preferable to maintain a constant tension even when the transport speed of the substrate film is changed or when transport is repeatedly stopped and started.

[0029] When the substrate film having the target coating has the coating continuously or intermittently along the longitudinal direction of the substrate film, it is preferable to transport the substrate film and perform coating peeling with the peeling member extending and fixed in the short direction of the substrate film. In particular, when the substrate film having the coating has the coating intermittently along the longitudinal direction of the substrate film or when the amount of coating formed on the substrate film varies along the longitudinal direction of the substrate film, it is preferable to adjust the transport speed of the substrate film to change the time for the coating to dissolve or swell with the cleaning liquid or the time for the coating to come into contact with the peeling member, thereby appropriately adjusting the coating peeling so as to perform more efficient coating peeling. The time for the coating to dissolve or swell, i.e., the time from application of the cleaning liquid to peeling of the coating with the peeling member, is preferably determined appropriately depending on the properties of the coating, but is preferably set to 0.05 to 10 seconds in consideration of the size of the device, etc.

[0030] Furthermore, when the substrate film having a coating has coatings at regular intervals in the longitudinal direction of the substrate film, the coating may be peeled off by conveying the substrate film a certain length, stopping the conveyance or changing the conveyance speed, and moving the peeling member relative to the portion of the substrate film where the coating is present. After the coating is peeled off, the conveyance may be restarted or the conveyance speed may be restored, which may enable highly efficient and reliable coating peeling. Furthermore, by stopping the conveyance or changing the conveyance speed during coating peeling, it is possible to check the substrate film after the coating has been peeled off and check whether any coating remains. The above inspection method may be any means that can detect the remaining coating.

[0031] In the coating peeling method of the present invention, the contact length in the longitudinal direction of the base film within the range where the peeling member is in contact with the coating surface of the base film having a coating is defined as L, and the contact length L [m] is defined as a vertical plane passing through the center position of the contact length and perpendicular to the surface of the peeling member, the side where the base film approaches the peeling member relatively is defined as the upstream side, and the side where the base film moves away from the peeling member relatively is defined as the downstream side. －５ ~1 x 10 －３ m, and the angle (acute angle) θ between the vertical plane and the base film located upstream of the vertical plane is １ [°], the angle (acute angle) θ between the vertical plane and the base film downstream of the vertical plane ２ [°], tension T applied to the base film upstream of the vertical plane １ [N / m], and the tension T applied to the base film downstream of the vertical plane ２ It is preferable to peel off the coating so that the strength [N / m] satisfies the following formula (1): Formula (1): 1.0×10 ６ ≦{T １ × cos(θ １ ) + T ２ × cos(θ ２ ) / L≦2.4×10 ８

[0032] The shorter the contact length L, the stronger the contact between the peeling member and the coating surface of the substrate film. However, as a result of extensive research by the inventors, it was found that the contact length L should be at least 5×10 －６ The limit of machining was 5 × 10 －６ Even if you try to process it to less than 5 x 10 mm, burrs will appear during processing, and even if you remove the burrs with abrasive paper or abrasive cloth, polishing marks will remain. －６ On the other hand, it was not possible to manufacture a contact length L of less than 1 × 10 －３ m, in order to satisfy the above formula (1), the tension T １ and T ２ is set large, and the angle θ between the vertical plane and the base film is set large. １ and θ ２ In this case, even if attempts are made to adjust the film peeling conditions to match the properties of the film to be peeled, the range that can be adjusted within the above formula (1) is narrow, and therefore film peeling is only possible for films that have properties that are relatively easy to peel.

[0033] In the coating peeling method of the present invention, when a rigid body such as a scraper or metal plate having a tip shape as shown in FIG. 2 is used as the peeling member, the peeling member has two surfaces including a ridge line where the peeling member starts to come into contact with the coating surface, and the surface facing the substrate film before coming into contact with the ridge line (hereinafter referred to as the upstream side surface r of the peeling member) １ The angle θ between the edge of the base film before contacting the ridge line ３ When the angle is set to less than 5°, the base film approaching the peeling member and the upstream side surface r of the peeling member may be separated. １ It was confirmed that the peeled coating (hereinafter referred to as peeled material) accumulated between the edge and the base film. When the coating was peeled continuously, it was occasionally the case that some of the accumulated peeled material spilled out onto the edge of the base film in the lateral direction and adhered to the side of the edge of the lateral direction of the base film or the back surface of the base film. On the other hand, the angle θ ３It was confirmed that by making the angle r 5° or more, the amount of accumulated peeled material was significantly reduced. １ The peeled material flowed along the strip and did not overflow in the short direction of the base film, and the coating could be peeled off stably and continuously.

[0034] [Coating Peeling Apparatus for Substrate Film Having a Coating] A preferred embodiment of the coating peeling apparatus 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.

[0035] 1 is a schematic diagram of a coating peeling apparatus 101 according to one embodiment of the present invention. The coating peeling apparatus 101 includes an unwinding device 4 that unwinds a substrate film 2 having a coating thereon and a winding device 5 that winds up the substrate film 3 after the coating has been peeled off. Between the unwinding device 4 and the winding device 5, the coating peeling apparatus 101 includes a drive device 9 for transporting the substrate film 2 having a coating thereon, a discharge head 6 as a cleaning liquid application mechanism for applying cleaning liquid 11 to the coating of the substrate film 2 having a coating thereon, a peeling member 7 for peeling both the coating of the substrate film 2 having a coating thereon and the cleaning liquid 11, and a drive device 10 for transporting the substrate film 3 after the coating has been peeled off. In addition to the discharge head 6, the cleaning liquid application mechanism also includes a liquid delivery pump 12 for delivering cleaning liquid 11 to the discharge head 6 and a tank (not shown) for storing the cleaning liquid.

[0036] The substrate film is transported by the drive devices 9 and 10, and the substrate film moves in its longitudinal direction relative to the peeling member 7. Furthermore, the drive devices 9 and 10 are preferably configured to be capable of tension cutting in order to stably transport the substrate film. When tension cutting is performed using a suction roll, a portion of the coating of the substrate film 2 having a coating may be sucked in, causing problems. Therefore, a configuration in which the substrate film is nipped between a metal drive roll and a rubber roll is more preferably used. The drive devices 9 and 10 also function as tension-applying mechanisms. Furthermore, it is preferable that the rotation speed of each drive roll of the drive devices 9 and 10 can be individually set, and that a mechanism (tension control mechanism) is provided that can control the tension applied to the substrate film in the longitudinal direction of the substrate film by controlling the rotation speed. This is not a limitation as long as the drive devices are equipped with a mechanism that can control the tension applied to the substrate film in the longitudinal direction of the substrate film. To control the tension, a tensiometer (not shown) may be installed between the drive device 9 and the peeling member 7, or between the peeling member 7 and the drive device 10, or both, and the measured tension may be fed back to the rotation speed of the drive rolls of the drive devices 9 and 10 to maintain a predetermined tension. Furthermore, an accumulator (not shown) may be provided on the unwinding device 4 side of the peeling member 7 so that the coating can be peeled off at a constant speed even when the speed at which the coated substrate film 2 is unwound from the unwinding device 4 is variable, thereby enabling intermittent transport of the coated substrate film 2 for purposes such as replacing the rolled substrate film 2 wound in a coated state and set in the unwinding device 4, dealing with operational problems that occur in the coating peeling device 101, or inspection before coating peeling. A dancer roll (not shown) may be provided between the drive devices 9 and 10 to reduce tension fluctuations that occur when the transport speed is changed. However, any means capable of varying the transport speed and reducing tension fluctuations may be used.

[0037] In this embodiment, the base film is transported by the drive devices 9 and 10, so that the base film moves in its longitudinal direction relative to the peeling member 7, but as long as the base film can move in its longitudinal direction relative to the peeling member 7, there is no need to be limited to a mechanism that transports the base film by the drive devices 9 and 10. A mechanism that moves the peeling member 7 relative to a stationary base film may be provided, or a mechanism that moves both the peeling member 7 and the base film may be used, or a mechanism that moves both in the same direction or in different directions may be used.

[0038] The discharge head 6 and peeling member 7, which are part of the cleaning liquid application mechanism, are surrounded by a booth 8. The discharge head 6 may be any type capable of discharging the cleaning liquid 11 and applying it to the coating surface of the substrate film 2, and examples thereof include, but are not limited to, a slit nozzle and a spray nozzle. The amount of cleaning liquid 11 applied to the coating surface of the substrate film 2 is set to 3 to 650 ml / m so as to be able to sufficiently dissolve the coating containing the water-soluble resin. ２ It is preferable that the amount of cleaning liquid 11 applied can be within the range of 100 to 1500. The specifications of the discharge head 6 and the liquid feed pump 12 are determined and adjusted so that the amount of cleaning liquid 11 required to peel off the coating can be applied to the coating surface of the substrate film 2 having the coating. The amount of cleaning liquid 11 applied can be controlled by using a metering pump as the liquid feed pump 12, or by installing a flow meter (not shown) between the liquid feed pump 12 and the discharge nozzle 6 and feeding back the indicated value of the flow meter. Alternatively, the amount of cleaning liquid 11 applied can be controlled by recovering the discharged cleaning liquid 11, determining the amount applied from its mass, and feeding back this information to the liquid feed pump.

[0039] The discharge head 6 and the peeling device 7 may be installed facing the coating surface of the coated substrate film 2. In Fig. 1, the coating is laminated on the underside of the substrate film 2, and the discharge head 6 and the peeling device 7 are installed facing the underside of the coated substrate film 2, but they are not limited to being installed on the underside of the substrate film 2. Furthermore, to accommodate the coating of the rolled substrate film 2 being on either the inside or outside of the roll, it is more preferable that the unwinding device has a mechanism that can accommodate either top- or bottom-unwinding, so that the unwinding direction of the coated substrate film 2 can be switched and the coated surface of the coated substrate film 2 can be conveyed facing the discharge head 6 and the peeling device 7.

[0040] The ejection head 6 is preferably capable of ejecting heated cleaning liquid 11 in order to quickly dissolve the water-soluble resin contained in the coating. The cleaning liquid 11 can be heated by providing a heat source such as a cartridge heater in the ejection head 6, or by heating a tank (not shown) that stores the cleaning liquid. Any means capable of heating the cleaning liquid 11 is acceptable, and is not limited to these. To more quickly dissolve the water-soluble resin contained in the coating, the cleaning liquid 11 may be ejected from the ejection head 6 in the form of steam. Since it is generally difficult to accurately measure the amount of steam ejected, the amount of cleaning liquid 11 dispensed can be determined by measuring the amount of liquid lost over a certain period of time from the tank storing the cleaning liquid 11. The material of the ejection head 6 is preferably heat-resistant in order to eject the heated cleaning liquid 11, and metal or a heat-resistant resin is preferably used.

[0041] 2 is a schematic cross-sectional view of the peeling member 7 of the first embodiment in the coating peeling apparatus 101. The peeling member 7 is in direct contact with the coating surface of the substrate film 2 having the coating, and the angle formed by the substrate film via the peeling member 7, i.e., the angle (θ １ +θ ２) is in the range of 20 to 150°. If the angle is less than 20°, the peeling member 7 may bend or vibrate when peeling the coating from the base film 2, or may be deformed or broken if the tension applied to the base film 2 is high, which may result in problems with peeling the coating. Furthermore, if the angle is greater than 150°, the force pressing the peeling member 7 against the base film 2 becomes weak. If the base film 2 is transported in this state and the coating is peeled off, even a slight change in the tension applied to the base film 2 may result in an insufficient force pressing the peeling member 7 against the base film 2, and the coating may not be peeled off, with part of the coating remaining on the base film.

[0042] The tension (T １ , T ２) is controlled by the tension control mechanism described above, and the tension is preferably adjustable within a range of 10 to 1000 N / m. The applied tension and the angle formed by the substrate film via the peeling member 7 can be adjusted depending on the properties of the coating on the substrate film 2 having the coating to be peeled. The higher the tension and the smaller the angle between the substrate films, the stronger the substrate film 2 having the coating can be pressed against the peeling member 7, thereby enabling more reliable peeling of the coating. However, if the pressing force is too strong, the breaking strength of the substrate film may be exceeded, causing the substrate film to break. If the substrate film breaks, continuous coating peeling cannot be performed, significantly reducing the operating efficiency of the coating peeling device 101. After extensive research, the inventors confirmed that by setting the tension to 1000 N / m or less, continuous coating peeling can be performed without breaking the substrate film, even when the angle formed by the substrate film is small. When the tension exceeded 1000 N / m, it was observed that the substrate film occasionally broke, starting from foreign matter attached to the tip of the peeling member 7 or small burrs generated during processing when manufacturing the peeling member 7. On the other hand, the lower the tension, the smaller the force pressing the peeling member 7 against the substrate film, making it more difficult to peel the coating. However, if the target coating had properties that allowed for easy peeling, peeling the coating was possible even with a small tension. However, when the tension was lowered, the transport condition of the substrate film significantly deteriorated. When the substrate film was transported at a tension of less than 10 N / m, the substrate film meandered during transport or wrinkled, resulting in areas in the width direction of the substrate film that were not in direct contact with the peeling member 7, making it impossible to peel the coating. The lower limit of the tension is preferably 50 N / m or more, and more preferably 100 N / m or more.

[0043] As shown in FIG. 2, the peeling member 7 in the peeling device 101 of the present invention is provided so as to be in direct contact with the coating surface of the substrate film 2 having a coating, and the angle (θ １ +θ ２In this state, the peeling member 7 is adjusted so that the contact length L in the longitudinal direction of the base film in the area in contact with the coating surface is 1×10 －５ ~1 x 10 －３ In this case, in order to increase the force with which the peeling member 7 is pressed against the base film, the shorter the contact length L, the better. Therefore, the inventors tried to make the part where the peeling member 7 comes into contact with the coating surface as sharp as possible, and as a result, it was found that the contact length L can be manufactured without generating warpage or burrs during processing when the contact length L is 5×10 －６ The contact length L was limited to 5 × 10 －６ When the contact length L is set to 1×10 m, under conditions where a strong force is applied to press the peeling member 7 against the base film, a strong force is applied locally, which may cause deformation of the tip of the peeling member 7. Therefore, in order to prevent deformation of the tip of the peeling member 7 under various conditions, the contact length L should be set to 1×10 －５ It has been found that it is more preferable to set the contact length L to 1×10 m or more. When the contact length L is long, the force pressing the peeling member 7 against the base film is dispersed over a wide area corresponding to the contact length L, making it difficult for the coating to peel off. As a result of extensive studies by the inventors, it has been found that the contact length L is 1×10 －３ By setting the contact length L to 1×10 m or less, even if the properties of the target coating changed, it was possible to peel off the coating by adjusting the amount of cleaning liquid 11 applied, the tension applied to the substrate film, and the angle formed between the substrate films via the peeling member 7. －３ When the thickness exceeds 100 mm, the force pressing the peeling member 7 against the substrate film becomes dispersed and small, making it difficult to peel the coating stably, and part of the coating remains.

[0044] Fig. 3 is a schematic diagram of the second peeling member 13 in the coating peeling apparatus 101 of the present invention. As shown in Fig. 3, the contact length L in the longitudinal direction of the substrate film in the range of contact of the peeling member 13 with the coating surface includes the case where the tip of the peeling member 13 is arc-shaped. Fig. 4 is a schematic diagram of the third peeling member 14 in the coating peeling apparatus 101 of the present invention. As shown in Fig. 4, when the range of contact of the peeling member 14 with the coating surface extends over multiple surfaces, the contact length L is L １ , L ２ , L３ In the peeling member 14, the contact length L is １ , L ２ , L ３ The sum is 1 x 10 －５ ~1 x 10 －３ It is preferable that the range is m.

[0045] The booth 8 of the stripping device 101 is provided to enclose the area from the discharge head 6 to the stripping device 7 in order to prevent the cleaning liquid 11 from scattering around and, when the cleaning liquid 11 is heated, to prevent the temperature of the cleaning liquid 11 from dropping. The material of the booth 8 is preferably heat-resistant because the inside of the booth 8 becomes hot, and metal, glass, or the like is preferably used.

[0046] It is more preferable to completely remove moisture from the substrate film 3 taken up by the take-up device 5 so that it can be stably produced as a recycled film after being remelted, and a drying device (not shown) may be provided between the peeling device 7 and the take-up device 5. The drying device may be provided before take-up, and may be located either before or after the drive device 10.

[0047] Furthermore, in order to check the quality of the base film 3 after the coating has been peeled off, an inspection machine (not shown) that detects coating residues or environmental foreign matter attached during the process may be provided before the winding device 5. The inspection machine may be selected according to the properties of the base film 3, and an inspection machine that uses transmitted light or reflected light is preferably used. Furthermore, a marking device (not shown) that records the location of coating residues or environmental foreign matter attached during the process detected by the inspection machine may be provided 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 detection target, such as a pen, sticker, or laser. Marking coating residues or environmental foreign matter attached during the process allows the locations to be removed before remelting, thereby enabling more stable production of recycled film and preventing deterioration in the quality of the recycled film.

[0048] In the coating peeling device of the present invention, the form of the substrate film having the coating may be in the form of cut sheets, but it is particularly preferred that the substrate film having the coating be wound into a roll. By unwinding the rolled substrate film having the coating, peeling the coating using the coating peeling device of the present invention, and winding up the substrate film after the coating has been peeled, the coating can be peeled continuously and efficiently.

[0049] Furthermore, in order to more efficiently dissolve and swell the coating by the cleaning solution 11 applied to the surface of the coated substrate film, a device for exposing a layer of the coating of the coated substrate film 2 that contains a large amount of water-soluble resin may be provided between the unwinding device 4 and the driving device 9. In particular, when the coating of the coated substrate film is a thermosetting silicone resin compound having dimethylsiloxane as its main skeleton, the coated substrate film is suitably used as a process release film due to its surface free energy characteristics. Specifically, it is used as a release film for providing a release object on the coating of the coated substrate film and then extracting the release object in a desired shape. Since the release object may remain on the coating surface of the coated substrate film after being used as such a process release film, it is preferable to provide a device for exposing the coating surface of the coated substrate film between the unwinding device 4 and the driving device 9 to expose the coating surface of the coated substrate film. The device for exposing the coating surface may be of a contact type or a non-contact type, and is appropriately selected depending on the remaining condition of the object to be released.

[0050] The material to be released is selected appropriately depending on the properties of the coating, but examples include inorganic materials such as metals applied by vapor deposition, adhesives made of organic materials such as acrylics applied by coating, and ceramic green sheets whose main component is barium titanate.

[0051] As described above, by using the coating peeling method and coating peeling device of the present invention, it is possible to dissolve the water-soluble resin from the surface of the film having the coating using a small amount of cleaning liquid, and to efficiently and reliably peel the coating. Furthermore, the coating peeling method and coating peeling device of the present invention can produce high-purity resin chips free of foreign matter at low cost without significantly increasing the environmental load, thereby enabling the stable production of recycled film.

[0052] The present invention will be described below with reference to examples, but the present invention is not necessarily limited thereto. <Substrate Film Having a Coating> The following coated film was prepared. <Coated Film> A coating of polyvinyl alcohol resin as a water-soluble resin was formed to a thickness of 0.1 μm on one side of a polyethylene terephthalate substrate film having a thickness of 30 μm and a width of 100 mm. Furthermore, a coating of curable silicone resin as a release component was formed thereon to a thickness of 0.1 μm as follows, with reference to the coating material described in JP 2015-189226 A: - Thermosetting silicone, manufactured by Shin-Etsu Chemical Co., Ltd., product name "KS-847T": 100 parts by mass; - Platinum catalyst, manufactured by Shin-Etsu Chemical Co., Ltd., product name "CAT-PL-50T": 3 parts by mass. The above was prepared by dissolving the above in a mixed solution of toluene and MEK as a solvent (toluene:MEK mass ratio 1:1) to a solids content of 1.8% by mass. Next, the release agent was applied onto the polyvinyl alcohol resin coating using a bar coater and dried in an oven at 90° C. for 20 seconds to form a coating of the release agent, thereby obtaining a coated film.

[0053] <Peeling Evaluation Method> (1) Peelability of Coating Peelability was evaluated using a commercially available dyne pen (surface energy: 30, 70 mN / m) by the following method. When a drawing was made on a sample surface with a dyne pen at room temperature (23°C) and the state was maintained for 4 seconds or more, it was determined that the surface energy of the sample surface was higher than that of the dyne pen. If the release component coating of the coated film remained on the surface, both of these surface energies were less than 30 mN / m, so the reagent was repelled by the sample surface with either dyne pen, and the drawing could not be maintained. On the other hand, when the release component coating was peeled off and the water-soluble polyvinyl alcohol resin was exposed, the surface energy was 70 mN / m or more, so both dyne pens could maintain the drawing. When both the release component coating and the water-soluble polyvinyl alcohol resin coating are peeled off and the polyethylene terephthalate is exposed, the surface energy is 43.8 mN / m, so a 30 mN / m dyne pen drawing is maintained, but a 70 mN / m dyne pen drawing is not maintained. The above evaluation method was used to determine whether the coating of the coated film was peeled off. If the release component coating of the film-coated film remains on the surface, the release component is mixed into the recycled resin chip, causing the recycled resin chip to become discolored (yellowing) and foreign matter to be generated, resulting in poor quality of the recycled resin chip and making it unusable. If the release component coating is peeled off but some of the water-soluble polyvinyl alcohol resin coating remains, the recycled resin chip will become slightly discolored (yellowing), and although the quality is slightly inferior to that of the raw material, it is still within the practical range. If both the release component coating and the water-soluble polyvinyl alcohol resin coating are peeled off, the recycled resin chip will have good quality.

[0054] (2) Quality of Recycled Resin Chips (i) Melt Film Formability After peeling the coating from the coated film, the substrate film is recovered. The recovered substrate film is crushed in a crusher, and the recycled resin chips are granulated in a granulator. The resulting recycled resin chips are dried at 180°C for 2 hours, then fed into an extruder and melt-extruded at 280°C. The resulting chips are then molded into a sheet on a cast drum cooled to 25°C, and it is confirmed whether a polyethylene terephthalate film can be produced without any problems. (ii) Intrinsic Viscosity The intrinsic viscosity IV(R) of the sheet obtained in (i) above is measured. The intrinsic viscosity IV(R) is measured by dissolving the polyethylene terephthalate film in 100 ml of orthochlorophenol (solution concentration C = 1.2 g / dl) and measuring the viscosity of the solution at 25°C using an Ostwald viscometer. The viscosity of the solvent is also measured in the same manner. Using the obtained solution viscosity and solvent viscosity, [η] (dl / g) is calculated according to the following formula (a), and the obtained value is taken as the intrinsic viscosity. (a) ηsp / C=[η]+K[η] ２ ・C (where ηsp=(solution viscosity (dl / g) / solvent viscosity (dl / g))-1, and K is the Huggins constant (assumed to be 0.343). Next, before producing the coated film, the intrinsic viscosity IV(I) of a sampled base film before forming the coating is measured in the same manner. Since a deterioration in the quality of resin chips caused by the inclusion of foreign matter or the like is expressed as the difference between IV(R) and IV(I), ΔIV is calculated using the following formula (b), and the obtained value is used to make the following judgment: (b) ΔIV=IV(R)-IV(I) * Difference in intrinsic viscosity is 0.05 or less: The quality of the recycled resin chips is within an acceptable range. * Difference in intrinsic viscosity is more than 0.05 and less than 0.2: The quality of the recycled resin chips is slightly inferior, but within the practical range. * Difference in intrinsic viscosity is more than 0.2: The quality of the recycled resin chips is not suitable for practical use.

[0055] Example 1 A coated film was set in the unwinding device 4 of the peeling device 101 shown in Figure 1. A spray nozzle (two-fluid system) was used as the discharge head 6 for discharging the cleaning liquid 11. The cleaning liquid was hot water at 60°C, and the discharge amount was 100 ml / min using a diaphragm pump. ２The peeling member 7 was a stainless steel plate having a tip shape as shown in FIG. －５ The angle (θ １ +θ ２ ) is 90° (θ １ : 45°, θ ２ The peeling member 7 was positioned so that the angle between the base film and the leading edge of the plate was 45°. As a result, the length L of direct contact between the base film and the leading edge of the plate in the conveying direction was 1.0 × 10 －５ It was confirmed that the film thickness was 1 m. The discharge head 6 and the peeling member 7 were positioned so that the base film reached the peeling member 7 1 second after hot water was applied by the discharge head 6. The base film was conveyed while applying a tension of 10 N / m in both directions in the longitudinal direction of the base film, thereby peeling off the coating. Furthermore, with the same device configuration, peeling of the coating was also carried out with tensions of 500 N / m and 1000 N / m.

[0056] The substrate film 3 was taken up by the take-up device 5, and the peeled state of the coating was checked with a dyne pen. When the tension was 1000 N / m, the amount of water added was 3 to 650 ml / m ２ It was confirmed that, when the tension was adjusted to the range of 10 to 650 ml / m, both the hardening type silicone resin and the water-soluble polyvinyl alcohol resin coating of the release component could be peeled off. ２ On the other hand, when the tension was adjusted to the range of 10 N / m, both the curable silicone resin and the water-soluble polyvinyl alcohol resin coatings of the release component could be peeled off. ２By carrying out the above steps, it was confirmed that both the release component coatings of the curable silicone resin and the water-soluble polyvinyl alcohol resin were peeled off. The substrate film 3 from which peeling of the coating was confirmed was then recovered, and a sheet was formed using the method described in (2)(i) above to produce a polyethylene terephthalate film. No bubbles or gels were observed in the molten polymer, and no abnormalities such as pressure increases occurred, allowing for the production of a polyethylene terephthalate film. The difference in intrinsic viscosity at each level is shown in Figure 5. The difference in intrinsic viscosity at each level was 0.2 or less, presenting no practical problems. It was confirmed that the greater the amount of moisture applied and the higher the applied tension, the smaller the difference in intrinsic viscosity, i.e., the better the quality of the recycled resin chips.

[0057] Example 2 A coated film was set in the unwinding device 4 of the peeling device 101 shown in FIG. ２ Furthermore, the angle (θ １ +θ ２ The angle (θ ) was 20° and the tension was 500 N / m. Otherwise, the peeling of the coating was carried out in the same manner as in Example 1. In addition, the angle (θ １ +θ ２ ) and change the angle (θ １ +θ ２ ) to 45° (θ １ : 22.5°, θ ２ :22.5°), 60°(θ １ : 30°, θ ２ :30°), 90°(θ １ : 45°, θ ２ :45°), 120°(θ １ : 60°, θ ２ :60°), 150°(θ １ : 75°, θ ２ :75°), 170°(θ １ : 45°, θ ２The coating was peeled off in the same manner under varying tensions of 10 N / m, 50 N / m, 100 N / m, 250 N / m, 500 N / m, 750 N / m, and 1000 N / m in both directions. The distance between the discharge head 6 and the peeling member 7 was adjusted so that the hot water reached the peeling member 7 one second after it was applied to the substrate film. The substrate film 3 was taken up by the winding device 5, and the peeled coating was sampled. The peeling state of the coating was confirmed using a dyne pen. Figure 6 shows the coating success or failure at each level. A circle in the figure indicates a condition in which it was confirmed that both the curable silicone resin and the water-soluble polyvinyl alcohol resin coatings, which are release components, were peeled off. A triangle in the figure indicates a condition in which the curable silicone resin was peeled off, but some polyvinyl alcohol resin remained on the surface of the substrate film. A cross in the figure indicates a condition in which both the curable silicone resin and the polyvinyl alcohol resin remained on the surface of the substrate film. From these results, it was confirmed that the more obtuse the angle between the coating-released substrate films and the lower the applied tension, the more the coating remained unpeeled.

[0058] The base film 3 was then recovered, crushed in a crusher, and made into resin chips in a granulator. The chips were then fed into an extruder, melt-extruded at 280°C, and formed into a sheet on a cast drum cooled to 25°C to produce a polyethylene terephthalate film. For the resin chips recovered under the conditions marked "x" in Figure 6, gel formation in the molten polymer occurred, and a polyethylene terephthalate film could not be obtained due to equipment abnormalities caused by pressure buildup. On the other hand, for the resin chips recovered under the conditions marked "△," no bubbles or gels were observed in the molten polymer, and no abnormalities such as pressure buildup occurred, resulting in a polyethylene terephthalate film. The difference in intrinsic viscosity was then confirmed, and it was found to be greater than 0.05 and less than 0.2 under all conditions, confirming that the quality of the recycled resin chips was somewhat inferior, but within the practical range. For the resin chips recovered under the conditions marked "○," a polyethylene terephthalate film could be stably obtained, and the difference in intrinsic viscosity was 0.05 or less, confirming that the quality of the recycled resin chips was acceptable.

[0059] Example 3 A coated film was set in the unwinding device 4 of the peeling device 101 shown in Figure 1. For the peeling member 7, several types of stainless steel plates with tip shapes as shown in Figure 2 were prepared, and the length L of direct contact between the tip and the base film in the conveying direction was changed. Specifically, L was 1.0 x 10 －５ , 2.5 × 10 －５ , 5.0 × 10 －５ , 1.0×10 －４ , 2.0 × 10 －４ , 5.0 × 10 －４ , 7.5 × 10 －４ , 1.0×10 －３ The plates were prepared so that the angle (θ １ +θ ２ The angle of the discharge head 6 was changed in the range of 20° to 150°, and the tension was also changed in the range of 10 to 1000 N / m. The distance between the discharge head 6 and the peeling member 7 was adjusted each time so that the hot water reached the peeling member 7 one second after it was applied to the base film. Otherwise, the coating was peeled off in the same manner as in Example 1.

[0060] The substrate film 3 was taken up by the take-up device 5, and the state of peeling of the coating was checked with a dyne pen. １ × cos(θ １ ) + T ２ × cos(θ ２ )} / L. The meanings of the symbols in the figure are the same as in Example 2. When the contact length L is 1×10 －５ ~1 x 10 －３ In the range of m, formula (1): 1.0 × 10 ６ ≦{T １ × cos(θ １ ) + T ２ × cos(θ ２ ) / L≦2.4×10 ８It was confirmed that the coating could be peeled off under the condition that satisfied the above. In particular, it was confirmed that the coating could be peeled off more easily as the contact length L was smaller. Then, after recovering the base film 3, it was crushed in a crusher and made into resin chips in a granulator. Thereafter, it was fed into an extruder, melt-extruded at 280°C, and formed into a sheet on a casting drum cooled to 25°C to produce a polyethylene terephthalate film. Regarding the levels at which a polyethylene terephthalate film could be produced, the difference in intrinsic viscosity was confirmed. For all levels that were marked with "△" or "◯" in Figure 7, the same results as in Example 2 were obtained.

[0061] Comparative Example 1 A coated film was set in the unwinding device 4 of the peeling device 101 shown in FIG. ２ The coating was peeled off in the same manner as in Example 1, except that the volume of the solution was adjusted to 2 ml per unit area. The substrate film 3 from which the coating had been peeled off was taken up using the winding device 5, and the peeled state of the coating was checked with a dyne pen. It was confirmed that both the coating of the curable silicone resin, which is the release component, and the coating of the water-soluble polyvinyl alcohol resin remained. Since it was confirmed that both coatings remained, no further evaluation was carried out.

[0062] Comparative Example 2 A coated film was placed in the unwinding device 4 of the peeling device 101 shown in FIG. 1 . A tension of 1100 N / m was applied to the substrate film in both longitudinal directions. Otherwise, the coating was peeled off in the same manner as in Example 1. Due to the high tension, corrugated iron-like wrinkles were generated in the substrate film in the conveyance direction. Because the wrinkles passed through the peeling member 7 as they were, it was visually confirmed that the coating remained in the same position in the film width direction as the wrinkles. The substrate film 3 from which the coating had been peeled was taken up by the winding device 5, and the peeled state of the coating was confirmed with a dyne pen. It was confirmed that both the curable silicone resin release component and the water-soluble polyvinyl alcohol resin coating remained in the same position in the film width direction as the wrinkles. Meanwhile, it was confirmed that both the curable silicone resin release component and the water-soluble polyvinyl alcohol resin coating were peeled off in the positions where no wrinkles occurred. Since it was difficult to extract only the portions from which all coatings had been peeled off from the recovered substrate film 3, further evaluation was not carried out.

[0063] The substrate film having a coating that can be applied to the coating peeling method and coating peeling device from a substrate film having a coating of the present invention is not limited to a film having a coating containing a water-soluble resin on one side of the substrate film, but may be a recyclable resin film, paper film, or metal film having a coating containing an easily soluble resin layer.

[0064] 2 Base film having coating 3 Base film 4 Unwinding device 5 Winding device 6 Discharge head 7, 13, 14 Peeling device 8 Booth 9, 10 Drive device 11 Cleaning liquid 12 Liquid supply pump

Claims

1. A method for peeling a coating containing a water-soluble resin from a substrate film having the coating on at least one side, in which a cleaning solution containing water as the main component is applied to the coating, and the surface area of ​​the coating is 1 m ２ a peeling member is brought into contact with the surface of the coating to which the cleaning solution has been applied, and the base film is moved in the longitudinal direction of the base film relative to the peeling member while setting an angle between the base film and the peeling member in the range of 20 to 150° and applying a tension in the range of 10 to 1000 N / m in at least one direction of the longitudinal direction of the base film, thereby peeling the coating from the base film.

2. The length in the longitudinal direction of the base film within the range where the peeling member is in contact with the surface of the coating is defined as the contact length, the plane passing through the center position of the contact length and perpendicular to the surface of the peeling member is defined as the vertical plane, the side where the base film approaches the peeling member relatively is defined as the upstream side, and the side where the base film moves away from the peeling member relatively is defined as the downstream side, and the contact length L [m] is 1 x 10 －５ ~1 x 10 －３ m, and the angle (acute angle) θ between the vertical plane and the base film located upstream of the vertical plane is １ [°], the angle (acute angle) θ between the vertical plane and the base film downstream of the vertical plane ２ [°], tension T applied to the base film upstream of the vertical plane １ [N / m], and the tension T applied to the base film downstream of the vertical surface ２ The coating peeling method according to claim 1, wherein the tension [N / m] satisfies the following formula (1): Formula (1): 1.0×10 ６ ≦{T １ × cos(θ １ ) + T ２ × cos(θ ２ ) / L≦2.4×10 ８ 3. A coating peeling method according to claim 1, wherein, of the two surfaces constituting the peeling member that sandwich the ridge line where the peeling member begins to come into contact with the surface of the coating, the surface facing the base film before coming into contact with the ridge line forms an angle of 5° or more with the base film before coming into contact with the ridge line.

4. The coating removal method according to any one of claims 1 to 3, wherein the coating contains a curable silicone resin.

5. An apparatus for peeling a coating containing a water-soluble resin from a substrate film having the coating on at least one surface thereof, the apparatus comprising: a cleaning liquid application mechanism for applying a cleaning liquid to the coating; a peeling member for peeling the coating to which the cleaning liquid has been applied from the substrate film; a drive device for moving the substrate film relative to the peeling member in the longitudinal direction of the substrate film; and a tension application mechanism for applying tension to the substrate film in at least one direction in the longitudinal direction, the cleaning liquid application mechanism applying the cleaning liquid to a surface area of ​​1 m of the coating. ２ the coating peeling device is adjusted to apply the cleaning liquid in an amount ranging from 3 to 650 ml per coating, the peeling member is positioned so that it comes into contact with the surface of the coating to which the cleaning liquid has been applied and that an angle formed by the base film via the peeling member is in a range of 20 to 150 degrees, and the tensioning mechanism is adjusted to apply a tension in a range of 10 to 1000 N / m.

6. The length of the base film in the longitudinal direction in the area where the peeling member contacts the surface of the coating is 1×10 －５ ~1 x 10 －３ 6. The coating stripping device of claim 5, wherein the thickness is in the range of m.

7. A coating peeling device according to claim 5 or 6, comprising: an unwinding device for unwinding the substrate film having the coating wound in a roll; and a winding device for winding up the substrate film from which the coating has been peeled off.