Method for removing coating layer and device for removing coating layer
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-02-03
- Publication Date
- 2026-08-13
Smart Images
Figure JP2026003706_13082026_PF_FP_ABST
Abstract
Description
Method for removing a coating layer and apparatus for removing a coating layer
[0001] The present invention relates to a method for removing a coating layer and an apparatus for removing a coating layer.
[0002] In recent years, from the perspective of protecting Earth's resources and the environment, there has been a growing movement in various fields to build a circular economy through efforts such as reducing waste generation, reusing, and recycling. For example, Patent Document 1 discloses a method for recycling plastic products having a painted film, characterized by peeling off the painted film formed on the plastic body with a high-pressure water jet, and then crushing and recycling the plastic body. Patent Document 2 discloses a method for peeling a laminated film, comprising at least the steps of unwinding the laminated film, supplying hot water to the surface of the unwinded laminated film, peeling off the surface laminated portion from the laminated film, and winding up the base film after peeling, characterized in that the surface laminated portion is peeled off after the hot water is brought into contact with the surface of the laminated film for two seconds or more. Patent Document 3 discloses a recycling system for recycling a plastic laminate having at least two or more layers into recycled raw materials, characterized in that it has a wet crushing equipment that separates the laminate into single layers while crushing the laminate in water or a cleaning agent by performing crushing and pressurizing simultaneously, and equipment that discharges and recovers the crushed mixture of each separated single layer.
[0003] Japanese Patent Publication No. 5-269743, Japanese Patent Publication No. 2004-363140, International Publication No. 2021 / 230033
[0004] In the technology of removing a coating layer from a laminated film, there is a demand to recycle the active ingredients contained in the coating layer. In the method described in Patent Document 1, by removing the painted film formed on the plastic body with high-pressure jet water, the plastic body can be recycled. Also, in the method described in Patent Document 2, using warm water, a two-layer surface laminate (water-soluble resin layer and surface functional layer) formed on the base film can be removed. However, in the methods described in Patent Documents 1 to 2, no consideration is given to the recovery of the components contained in the painted film or the surface laminate. Also, in the method described in Patent Document 3, by crushing and pumping a plastic laminate with a wet crushing facility, two or more layers can be separated into single layers. However, in the method described in Patent Document 3, since each separated single layer is recovered as a crushed mixture, it is difficult to recover the components contained in a specific layer.
[0005] An object of the present invention is to provide a method for removing a coating layer and a coating layer removing apparatus that can efficiently recycle the active ingredients contained in the coating layer.
[0006] [1] A method for removing a coating layer from a laminated film having a base film and two or more coating layers, wherein the two or more coating layers include at least a first layer and a second layer, and the second layer and the first layer are arranged in this order from the base film side toward the outermost surface layer of the coating layer, comprising: a first spraying step of spraying water onto the first layer of the laminated film with a water pressure that removes the first layer of the laminated film and leaves the second layer of the laminated film; a second spraying step of spraying water onto the second layer of the laminated film with a water pressure that removes the second layer remaining on the laminated film; and a base material recovery step of recovering the base film after the first and second layers have been removed from the laminated film. [2] The method for removing a coating layer according to [1], wherein the water pressure of the water sprayed onto the second layer is higher than the water pressure of the water sprayed onto the first layer. [3] A method for removing a coating layer according to [1] or [2], further comprising the steps of: preparing a laminated film roll in which the laminated film is wound in a roll shape; and unwinding the laminated film from the laminated film roll, wherein the substrate recovery step is a step of winding the substrate film into a roll shape and recovering it, and the preparation step, the unwinding step, the first spraying step, the second spraying step, and the substrate recovery step are performed in this order, and the steps from the unwinding step to the substrate recovery step are performed roll to roll. [4] A method for removing a coating layer according to any one of [1] to [3], wherein the second layer includes a release agent layer. [5] A method for removing a coating layer according to [4], wherein the first layer includes a ceramic green sheet. [6] A method for removing a coating layer according to [4], wherein the first layer is a multilayer including a green sheet composed of a dielectric as an active ingredient and a conductive layer composed of a conductor as an active ingredient. [7] A method for removing a coating layer according to any one of [1] to [6], comprising a first desorbent recovery step of filtering water containing the first desorbent, which is a first desorbent derived from the first layer that has been removed in the first injection step.[8] The method for removing a coating layer according to [3], further comprising a step of detecting the presence or absence of the first or second layer after the first injection step and before the second injection step. [9] The method for removing a coating layer according to [8], wherein the detection step is a step of measuring the thickness of the laminated film in-line with a film thickness gauge.
[0007]
[10] A coating layer removal device for removing a coating layer from a laminated film having a base film and two or more coating layers, wherein the two or more coating layers include at least a first layer and a second layer, and the second layer and the first layer are arranged in this order from the base film side toward the outermost layer side of the coating layer, and the device includes a feed shaft for feeding the laminated film from a laminated film roll in which the laminated film is wound in a roll shape, a first backup roller arranged downstream of the feed shaft for transporting the laminated film downstream, a first spray unit including one or more first nozzles arranged opposite to the first backup roller for spraying water from the first nozzles onto the first layer at a nozzle pressure P1 so as the laminated film passes the first backup roller, and a second backup roller arranged downstream of the first spray unit for transporting the laminated film downstream, A coating layer removal device comprising: a second spraying unit that sprays water from the second nozzles onto the second layer at a nozzle pressure P2 higher than the nozzle pressure P1, including one or more second nozzles positioned opposite the second backup roller, so as the laminated film passes the second backup roller, the second spraying unit that supplies water to the first spraying unit and the second spraying unit, respectively; and a winding shaft that winds the base film into a roll shape after the first and second layers have been removed from the laminated film, wherein the water supplying unit includes one or more pumps, and the first spraying unit and the second spraying unit are connected to at least one of the one or more pumps.
[11] The coating layer removal device according to
[10] , further comprising a nozzle pressure control unit that controls the nozzle pressure P1 and the nozzle pressure P2, the nozzle pressure control unit being connected to the one or more pumps.
[12] The coating layer removal apparatus according to
[10] or
[11] , further comprising a first desorbent recovery unit for filtering water containing the first desorbent, which is a first desorbent derived from the first layer removed by the first injection unit, and recovering the first desorbent.
[13] The coating layer removal apparatus according to any one of
[10] to
[12] , further comprising a detection unit for detecting the presence or absence of the first or second layer, located downstream of the first injection unit and upstream of the second injection unit.
[0008] According to one aspect of the present invention, a method for removing a coating layer and an apparatus for removing a coating layer can be provided that allow for the efficient regeneration and utilization of the active ingredients contained in the coating layer.
[0009] A cross-sectional view of a first example of a laminated film used in the removal method according to the first embodiment. A perspective view of a second example of a laminated film used in the removal method according to the first embodiment. A schematic diagram of an example of a removal device according to the second embodiment. A schematic diagram of an example of a removal device according to the third embodiment.
[0010] In this specification, ordinal numbers such as "first" and "second" are used to distinguish components and do not indicate order. In this specification, expressions without ordinal numbers, such as "injector," are a general term for injection units and are used when describing injection units that have ordinal numbers such as "first" and "second." For example, when a description is made that applies to multiple components that are indicated with ordinal numbers, such as "first injection unit" and "second injection unit," the term "injector" without the ordinal number is used to collectively refer to "first injection unit" and "second injection unit." In this specification, numerical ranges indicated using "~" mean a range that includes the number written before "~" as the lower limit and the number written after "~" as the upper limit.
[0011] [First Embodiment] [Method for Removing Coating Layers] The method for removing coating layers according to this embodiment (hereinafter also referred to as the removal method according to this embodiment) is a method for removing coating layers from a laminated film having a base film and two or more coating layers, wherein the two or more coating layers include at least a first layer and a second layer, and the second layer and the first layer are arranged in this order from the base film side toward the outermost surface layer of the coating layers. The removal method according to this embodiment includes a first spraying step of spraying water onto the first layer of the laminated film with water pressure that removes the first layer of the laminated film and leaves the second layer of the laminated film, a second spraying step of spraying water onto the second layer of the laminated film with water pressure that removes the second layer remaining on the laminated film, and a base material recovery step of recovering the base film after the first and second layers have been removed from the laminated film.
[0012] In the removal method according to this embodiment, the water pressure injection process is divided into two stages (first injection process and second injection process), so that the first and second layers constituting the coating layer can be removed individually. This makes it easy to recover active ingredients that you want to recycle, for example, if the first or second layer contains such active ingredients. As a result, the active ingredients contained in the coating layer can be efficiently recycled. Examples of active ingredients contained in the coating layer include ceramics, dielectrics, and conductors (e.g., copper, silver, and rare metals). According to the removal method according to this embodiment, it becomes easy to recycle active ingredients that are conventionally difficult to separate. Furthermore, according to the removal method according to this embodiment, since it uses substantially only water without using chemicals, there is no need to treat waste liquid containing chemicals, so waste liquid treatment costs can be kept low, and the impact on the global environment can also be reduced.
[0013] In the removal method according to this embodiment, the water used in the first injection step and the water used in the second injection step are water for removing the coating layers (first and second layers), and the water pressure is adjusted. The water is preferably ordinary water, i.e., industrial water, and may be purified water or distilled water. It may also be recycled wastewater used in various industrial productions, or recycled wastewater after it has been used in the implementation of this embodiment. If wastewater is recycled, it may be treated to regenerate the wastewater as appropriate. From the viewpoint of improving work efficiency, the water may contain additives that add functionality as appropriate, but it is preferable not to include them. Examples of additives include surfactants and water-soluble organic solvents. If the water contains additives, the concentration of the active ingredients of the additives in the water is preferably 0.2% by mass or less, more preferably 0.1% by mass or less, relative to the total amount of water, and furthermore, it is preferable that the water is not water to which additives have been intentionally added. Furthermore, it is preferable that the water is not an alkaline aqueous solution prepared by intentionally adding a basic substance, nor is it preferable that it is an acidic aqueous solution prepared by intentionally adding an acidic substance. Since wastewater can potentially be treated with simple recycling methods, the water may contain basic and acidic substances as additives. In such cases, it is preferable that the pH of the water be between 5.8 and 8.6 to comply with the uniform wastewater discharge standards (other items) based on the Water Pollution Control Law. The water used is preferably at room temperature and may be either cold or warm water.
[0014] Figure 1 is a cross-sectional view of a first example of a laminated film used in the removal method according to the first embodiment. The laminated film 90 has a base film 91 and a coating layer 94. The coating layer 94 includes a first layer 93 and a second layer 92, and the second layer 92 and the first layer 93 are arranged in this order from the base film 91 side toward the outermost layer side of the coating layer 94. The base film 91 has a first base surface 91a and a second base surface 91b opposite to the first base surface 91a. The base film 91 and the second layer 92 are directly laminated, and the first layer 93 and the second layer 92 are directly laminated. In the laminated film 90, it is preferable that the second layer 92 includes a release agent layer. In the laminated film 90, it is preferable that the first layer 93 includes a ceramic green sheet. In particular, it is preferable that the ceramic green sheet is a green sheet composed of a dielectric as an active ingredient. The first layer 93 may be a multilayer including, from the side of the second layer 92, a green sheet composed of a dielectric as an active ingredient and a conductive layer composed of a conductor as an active ingredient. The green sheet is an unfired sheet-like material, and a green sheet with ceramics as an active ingredient is called a ceramic green sheet.
[0015] Figure 2 is a perspective view of a second example of a laminated film used in the removal method according to the first embodiment. Figure 2 shows a laminated film after it has been used in the manufacture of a multilayer ceramic capacitor (MLCC), and after the necessary portion of the ceramic green sheet has been peeled off. The laminated film 90A is wound around a core 1G to form a roll (laminated film roll). An insertion hole 2G is provided in the central part of the core 1G. The laminated film 90A has a base film 91 and a coating layer 94A. The coating layer 94A includes a release agent layer as a second layer 92 and a ceramic green sheet (residue) as a first layer 93A, starting from the side of the base film 91. The base film 91 and the second layer 92 are directly laminated, and the first layer 93A and the second layer 92 are directly laminated. The ceramic green sheet (first layer 93A) is partially provided on the surface of the release agent layer (second layer 92). After the ceramic green sheet is peeled off, a recess 930 is formed, and the release agent layer is exposed from the recess 930. In Figure 2, the first layer 93A may be a multilayer including the ceramic green sheet and a conductive layer (not shown) composed of a conductor as an active ingredient, from the side of the second layer 92.
[0016] In the first embodiment, the dimensions of the laminated film are, for example, a width of 100 mm or more and 1000 mm or less, preferably 200 mm or more and 600 mm or less. The length of the laminated film is, for example, 50 m or more and 30000 m or less, preferably 100 m or more and 10000 m or less. If the laminated film is a roll, the winding diameter of the roll (the diameter of the roll including the core) is, for example, 100 mm or more and 1500 mm or less, preferably 150 mm or more and 1000 mm or less.
[0017] The steps of the removal method according to the first embodiment will be described below.
[0018] <First Injection Step> The first injection step is a step in which water is injected into the first layer of the laminated film with a water pressure that removes the first layer of the laminated film while leaving the second layer of the laminated film. In this specification, the water pressure when injecting water means the nozzle pressure (water pressure applied to the nozzle outlet). In the first injection step, the "water pressure that removes the first layer of the laminated film while leaving the second layer of the laminated film" is determined by conducting tests in advance for each type of laminated film according to the structure and characteristics of the first and second layers. It is preferable that the water pressure of the water injected into the second layer in the second injection step is higher than the water pressure of the water injected into the first layer in the first injection step. This makes it easier to remove the first layer and leave the second layer in the first injection step, and then remove the second layer in the subsequent second injection step. Hereinafter, the nozzle pressure in the first injection step may be referred to as nozzle pressure P1, and the nozzle pressure in the second injection step may be referred to as nozzle pressure P2.
[0019] As a method for making the water pressure (nozzle pressure P2) of the water injected into the second layer in the second injection step higher than the water pressure (nozzle pressure P1) of the water injected into the first layer in the first injection step, examples include the following methods (i) to (iii): (i) Adjust the diameter of the nozzle outlet used in each injection step. For example, make the diameter of the nozzle outlet used in the first injection step larger than the diameter of the nozzle outlet used in the second injection step. (ii) Perform the first injection step using a first pump (first supply pump 51 in the case of Figure 3) that generates the nozzle pressure P1 derived in advance by testing, and perform the second injection step using a second pump (second supply pump 52 in the case of Figure 3) that generates the nozzle pressure P2 derived in advance by testing. (iii) Select the nozzle pattern to be used in each injection step. In the case of (ii) above, the first pump and the second pump may be controlled by a nozzle pressure control unit (e.g., a computer) to generate the nozzle pressure P1 and nozzle pressure P2.
[0020] In the first injection step, the nozzle pressure P1 is preferably lower than the nozzle pressure P2 in the second injection step, for example, 3.0 MPa or more and 15 MPa or less, and more preferably 5.0 MPa or more and 10 MPa or less.
[0021] Each spraying step (first spraying step and second spraying step) is preferably a step in which water is sprayed toward the coating layer of the laminated film while the laminated film is supported by a backup roller. In this case, in the first spraying step, it is preferable that water is sprayed toward the coating layer of the laminated film from one or more nozzles positioned opposite the backup roller while the backup roller is in contact with the second substrate surface 91b (Figure 1) of the base film.
[0022] <Second Injection Step> The second injection step is a step in which water is injected into the second layer of the laminated film at a water pressure that removes the second layer remaining on the laminated film. The "water pressure that removes the second layer remaining on the laminated film" is preferably determined by conducting tests in advance for each type of laminated film, similar to the water pressure in the first injection step. In the second injection step, the nozzle pressure P2 is preferably higher than the nozzle pressure P1 in the first injection step, for example, 10 MPa or more and 50 MPa or less, and more preferably 15 MPa or more and 25 MPa or less. The difference between the nozzle pressure P2 and the nozzle pressure P1 (nozzle pressure P2 - nozzle pressure P1) is, for example, 1.0 MPa or more, and preferably 2.0 MPa or more and 10.0 MPa or less.
[0023] <Substrate Recovery Process> The substrate recovery process is the process of recovering the substrate film after the first and second layers have been removed from the laminated film. The substrate film is recovered by a known method. When the removal method according to this embodiment is performed roll-to-roll, the substrate recovery process is the process of recovering the substrate film by winding it into a roll.
[0024] <Detection Step> The removal method according to this embodiment preferably includes a step of detecting the presence or absence of the first or second layer after the first injection step and before the second injection step. By performing the detection step, it can be confirmed that the first layer has been removed before the second injection step. The detection step is preferably a step of measuring the thickness of the laminated film inline with a film thickness gauge. The detection step may also be performed by irradiating the laminated film with electromagnetic waves or ultrasonic waves and detecting the reflected waves reflected from the laminated film to detect the presence or absence of the first or second layer. Electromagnetic waves include visible light, ultraviolet rays, or infrared rays. The detection step may also be performed by detecting the transmitted waves that pass through the laminated film to detect the presence or absence of the first or second layer.
[0025] <First Delamination Recovery Step> The removal method according to this embodiment preferably includes a first delamination recovery step in which the first delamination, which is a first delamination derived from the first layer removed in the first injection step, is recovered by filtering the water containing the first delamination. A means for recovering the first delamination can be, for example, a filtration filter. The same applies to the means for recovering the second delamination. By performing the first delamination recovery step, the active ingredients (e.g., dielectrics and conductors) contained in the first layer can be recovered efficiently. Recovery of the delamination (first delamination and second delamination) is carried out, for example, by the following steps (1) to (4). The delamination is recovered in (2) and (4) below. (1) The water containing the delamination is coarsely filtered with a filter of 200 mesh to 1000 mesh (more preferably 400 mesh to 800 mesh). A screen filter can be used as the filter. (2) The delamination captured in (1) is scraped off the filter surface with a blade or the like and recovered. (3) The filtrate from (1) is precisely filtered using a filter with a diameter of 0.050 μm to 10 μm. For example, a membrane filter can be used as the filter. (4) The first detached material captured in (3) is scraped off the filter surface with a blade or the like and recovered. It is preferable that the filtrate obtained in (2) and (4) is circulated through a pump and reused as water for the first and second injection processes.
[0026] <Second Desorbed Material Recovery Step> The removal method according to this embodiment may include a second desorbed material recovery step in which the second desorbed material, which originates from the second layer and was removed in the second injection step, is recovered by filtering the water containing the second desorbed material.
[0027] <Roll-to-Roll> The removal method according to this embodiment further comprises the steps of preparing a laminated film roll in which the laminated film is wound in a roll shape, and unwinding the laminated film from the laminated film roll. The preparation step, the unwinding step, the first spraying step, the second spraying step, and the substrate recovery step are performed in this order, and it is preferable that the steps from the unwinding step to the substrate recovery step are performed roll-to-roll. By performing the removal method according to this embodiment roll-to-roll, the active ingredients contained in the coating layer can be continuously recovered.
[0028] <Process of circulating to the pump> When the removal method according to this embodiment is carried out roll-to-roll, it is preferable to have a process of circulating the water filtered in the first desorbed material recovery process and the second desorbed material recovery process to the pump. It is preferable to reuse the water circulated to the pump as water used in the first injection process and the second injection process.
[0029] <Water Removal Process> When the removal method according to this embodiment is carried out roll-to-roll, it is preferable to have a water removal process for the base film after the second spraying process and before the base film recovery process. The means for water removal from the base film are not particularly limited, but examples include a water removal nozzle (also called an air knife) and a dryer.
[0030] [Second Embodiment] [Coating Layer Removal Apparatus] In the second embodiment, the X-axis, Y-axis, and Z-axis are orthogonal to each other, the X-axis and Y-axis are axes in a predetermined plane, and the Z-axis is an axis orthogonal to the predetermined plane. Furthermore, in the second embodiment, when directions are indicated based on the view from the front direction of Figure 3, which is parallel to the Y-axis, "up" is the direction of the Z-axis arrow and "down" is the opposite direction, "right" is the direction of the X-axis arrow and "left" is the opposite direction, "front" is the front direction of Figure 3, which is parallel to the Y-axis and "back" is the opposite direction. Also, in Figure 3, the side closer to the feed shaft 10 is called the "upstream side", and the side closer to the winding shaft 40 is called the "downstream side".
[0031] Figure 3 is a schematic diagram of the coating layer removal device 100 according to the second embodiment. The removal device 100 is a device that removes the coating layer from a laminated film while continuously conveying the laminated film roll-to-roll. In the second embodiment, an example of removing the coating layer 94 (first layer 93 and second layer 92) from the laminated film 90 shown in Figure 1 using the removal device 100 will be described.
[0032] The removal device 100 according to the second embodiment includes a feed shaft 10 that feeds out the laminated film 90 from a laminated film roll in which the laminated film 90 is wound in a roll shape, a first backup roller 21 positioned downstream of the feed shaft 10 and transporting the laminated film 90 downstream, a first spray unit 31 positioned opposite the first backup roller 21 and including one or more first nozzles that spray water W3 from the first nozzles onto the first layer 93 at a nozzle pressure P1 so as the laminated film 90 passes the first backup roller 21 to remove the first layer 93, and a removal device positioned downstream of the first spray unit 31, The device includes a second backup roller 22 for transporting the film 90 downstream, a second injection unit 32 which includes one or more second nozzles positioned opposite the second backup roller 22 and injects water W4 from the second nozzles onto the second layer 92 at a nozzle pressure P2 higher than the nozzle pressure P1 so as the laminated film 90 passes the second backup roller 22 to remove the second layer 92, a water supply unit 50 which supplies water to the first injection unit 31 and the second injection unit 32, respectively, and a winding shaft 40 which winds the base film 91 into a roll after the first layer 93 and the second layer 92 have been removed from the laminated film 90. The water supply unit 50 includes one or more pumps (in the case of Figure 3, a first supply pump 51 and a second supply pump 52). The first injection unit 31 and the second injection unit 32 are connected to at least one of the one or more pumps.
[0033] In the second embodiment, the removal device 100 includes a first desorbent recovery unit 71 that recovers the first desorbent, which originates from the first layer 93 removed by the first injection unit 31, by filtering the water containing the first desorbent. The removal device 100 also includes a second desorbent recovery unit 72 that recovers the second desorbent, which originates from the second layer 92 removed by the second injection unit 32, by filtering the water containing the second desorbent. The removal device 100 also includes a detection unit 75 located downstream of the first injection unit 31 and upstream of the second injection unit 32 for detecting the presence or absence of the first layer 93 or the second layer 92. The removal device 100 also includes a residue removal device 70, nip rollers NR1 and NR2, and a plurality of guide rollers GR. Known rollers can be used as the guide rollers GR.
[0034] According to the removal device 100 of the second embodiment, by comprising a first injection unit 31 that injects water from a first nozzle onto the first layer 93 at a nozzle pressure P1, and a second injection unit 32 that injects water from a second nozzle onto the second layer 92 at a nozzle pressure P2 higher than the nozzle pressure P1, the first layer 93 and the second layer 92 constituting the coating layer can be removed individually. Furthermore, the removal device 100 is equipped with a first desorbed material recovery unit 71 that recovers the first desorbed material originating from the first layer 93, so that if the first layer 93 contains an active ingredient (e.g., a dielectric), the active ingredient can be easily recovered. As a result, the active ingredient contained in the coating layer can be efficiently recycled. In addition, it becomes possible to recycle active ingredients that were conventionally discarded.
[0035] The components of the removal device 100 according to the second embodiment will now be described.
[0036] <Feeding shaft 10> The feeding shaft 10 feeds out the roll-shaped laminated film 90. The feeding shaft 10 is connected to a drive roller (not shown).
[0037] <First backup roller 21, second backup roller 22> The first backup roller 21 is positioned downstream of the feed shaft 10 and upstream of the winding shaft 40. The second backup roller 22 is positioned downstream of the first backup roller 21 and upstream of the winding shaft 40. The backup rollers 21 and 22 are positioned in contact with the second base material surface 91b (Figure 1) of the base film 91. By passing the laminated film 90 over the backup rollers 21 and 22, the vertical (Z-axis direction) play (escape) of the laminated film 90 caused by the collision of water W3 and W4 from the nozzle is eliminated, and the tension in the surface direction of the laminated film 90 can be made uniform. This maximizes the effect of the collision force of water W3 and W4.
[0038] <First Injection Section 31, Second Injection Section 32> The injection sections 31 and 32 include one or more nozzles positioned opposite the backup rollers 21 and 22. From the viewpoint of applying impact stress to the surface of the first layer 93, when viewed in a cross-section perpendicular to the central axis 21a of the first backup roller 21, it is preferable that the central axes of the one or more nozzles of the first injection section 31 are perpendicular to the outer tangent PT1 of the first backup roller 21. Similarly, from the viewpoint of applying impact stress to the surface of the second layer 92, when viewed in a cross-section perpendicular to the central axis 22a of the second backup roller 22, it is preferable that the central axes of the one or more nozzles of the second injection section 32 are perpendicular to the outer tangent PT2 of the second backup roller 22.
[0039] The injection units 31 and 32 are located within injection chambers 301 and 302, respectively, and are configured so that the injected water is guided to the second tank 63 of the water recovery and regeneration device 60 via the outlets 1a and 2a.
[0040] The nozzle shape is not particularly limited, but a constricted flow nozzle is preferred. A constricted flow nozzle is a nozzle that ejects water from a constricted outlet, such as an orifice or a flow nozzle. When the nozzle is a constricted flow nozzle, the inner diameter of the nozzle outlet is the inner diameter of the constricted section. The nozzle pattern is not particularly limited, but examples include a flat pattern (ejection in a fan shape from the outlet), a full cone pattern (ejection in a cone shape from the outlet), and a straight pattern (ejection in a linear shape from the outlet). Among these, a flat pattern is preferred. As shown in Figure 3, when removing the target layer (first layer 93 and second layer 92) using a roll-to-roll method, a flat pattern can crush and remove the target layer with fewer nozzles and less water compared to a straight pattern.
[0041] <Water Supply Unit 50> The water supply unit 50 is, for example, a known water supply device or pressurized water generator. The water supply unit 50 includes a water source 55, a first tank 53 for storing water W1 supplied from the water source 55, piping 54 connecting the water source 55 and the first tank 53, and two supply pumps 51 and 52. The first supply pump 51 is connected to tanks 53 and 63 via piping 531 and 631, respectively, and is also connected to a first injection unit 31 via piping 511. The second supply pump 52 is connected to tanks 53 and 63 via piping 532 and 632, respectively, and is also connected to a second injection unit 32 via piping 521. The second tank 63 stores used and recycled water (also referred to as recycled water W2). In the water supply unit 50, when supplying water or generating pressurized water, water W1 stored in the first tank 53 and recycled water W2 stored in the second tank 63 are used. The supply pumps 51 and 52 pressurize the water W1 and recycled water W2 to a predetermined water pressure and supply water W3 and W4 to the injection units 31 and 32.
[0042] <Water Recovery and Recycling Device 60> The water recovery and recycling device 60 separates the water ejected from the injection units 31 and 32 into water and detached material in the detached material collection units 71 and 72, and then stores the separated water as recycled water W2 in the second tank 63. The water recovery and recycling device 60 comprises the second tank 63, the detached material collection units 71 and 72, and the recovery pumps 61 and 62 positioned between the second tank 63 and the detached material collection units 71 and 72.
[0043] <First Debris Recovery Unit 71, Second Debris Recovery Unit 72> The debris recovery units 71 and 72 each include filtration filters 711 and 721 and storage units 712 and 722. The debris recovery units 71 and 72 separate the water ejected from the injection units 31 and 32 into water and debris by passing it through the filtration filters 711 and 721. The first storage unit 712 stores the first debris originating from the first layer 93. The second storage unit 722 stores the second debris originating from the second layer 92. Examples of storage units 712 and 722 include known containers.
[0044] <Residue Removing Device 70>The residue removing device 70 is a device for removing residues adhering to the base film 91, and is an example of a means for draining the base film. The residue removing device 70 is disposed downstream of the second backup roller 22 and upstream of the winding shaft 40. The residues are, for example, the second layer 92 remaining on the base film 91, as well as water and foreign substances adhering to the base film 91. The residue removing device 70 is not particularly limited, and examples thereof include the aforementioned draining means. The residue removing device 70 may be disposed at least on the side of the second layer 92. In the case of FIG. 3, the residue removing device 70 is a pair of draining nozzles.
[0045] <Detection Unit 75>The detection unit 75 is a device for detecting the presence or absence of the first layer 93 or the second layer 92, and is disposed downstream of the first injection unit 31 and upstream of the second injection unit 32. The detection unit 75 is, for example, a film thickness gauge for measuring the film thickness of the coating layer 94. Further, the detection unit may be a means (for example, an optical sensor) for detecting a reflected wave or a transmitted wave from the laminated film.
[0046] <Winding Shaft 40> The winding shaft 40 winds up the base film 91 after the second layer 92 has been removed in a roll shape. The winding shaft 40 is connected to a driving roller (not shown).
[0047] [Third Embodiment] [Coating Layer Removal Device] The coating layer removal device 100A according to the third embodiment will be described. In the third embodiment, the description will focus on the differences from the second embodiment, and the description of the same matters will be omitted or simplified by using the same reference numerals. FIG. 4 is a schematic diagram of the coating layer removal device 100A according to the third embodiment. The removal device 100A according to the third embodiment is the same as the removal device 100 described in the second embodiment, except that it includes a nozzle pressure control unit 85. The nozzle pressure control unit 85 controls the nozzle pressure P1 and the nozzle pressure P2. The nozzle pressure control unit 85 is connected to one or more pumps that supply water to the first injection unit 31 and the second injection unit 32, respectively. In the case of FIG. 4, the nozzle pressure control unit 85 is connected to the first supply pump 51 and the second supply pump 52, and controls the first supply pump 51 and the second supply pump 52 so as to generate the nozzle pressure P1 and the nozzle pressure P2, respectively. The nozzle pressure control unit 85 controls (monitors) the first supply pump 51 and the second supply pump 52 so that the nozzle pressure P1 and the nozzle pressure P2 are within the set range during the operation of the removal device 100A. The nozzle pressure control unit 85 is, for example, a computer.
[0048] The present invention is not limited to the above embodiments. The present invention can include modifications, improvements, etc. within the scope that can achieve the object of the present invention.
[0049] The configuration of the laminated film will be described.
[0050] [Laminated Film] The laminated film used in the above-described embodiment comprises a base film and two or more coating layers. The two or more coating layers are arranged in the order of the second layer and the first layer, from the base film side toward the outermost layer of the coating layer. The first layer may be a single layer or a multilayer consisting of two or more layers of the same or different type. The second layer may be a single layer or a multilayer consisting of two or more layers of the same or different type. The first layer may be placed on at least a part of the surface of the second layer or on the entire surface of the second layer. From the viewpoint of making it easier to remove the coating layer from the laminated film and recover the remaining base film, it is preferable that the base film and the coating layer are directly laminated. Here, "direct lamination" refers to a configuration in which the base film and the coating layer are in direct contact with each other, for example, without any other layers between the base film and the coating layer.
[0051] <Base Film> The base film used is a resin film on which the resin component intended for recovery has been formed. Suitable resin films include polyester films such as polyethylene terephthalate film, polybutylene terephthalate, and polyethylene naphthalate; polyolefin films such as polyethylene film and polypropylene film; polyimide film; polyamide film; polycarbonate film; polyacetate film; ethylene-vinyl acetate copolymer (EVA) film; ethylene-(meth)acrylic acid copolymer film; ethylene-(meth)acrylic acid ester copolymer film; cycloolefin polymer film; polyurethane film; polyphenylene sulfide film; cellophane; and others. Among the base films, polyester film is preferred due to its excellent heat resistance and strength. As for polyester films, polyester films with polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate as the main constituent component are preferred from the viewpoint of facilitating resin recovery and regeneration. In this specification, the main constituent component or principal component means that the proportion of the total mass of the material is 50% by mass or more. Furthermore, the resin film may contain known fillers, colorants, antistatic agents, antioxidants, organic lubricants, and catalysts. The resin film may be transparent or colored as desired. In addition, at least one surface of the base film may be subjected to surface treatment such as sputtering, corona discharge, flame, ultraviolet irradiation, electron beam irradiation, and oxidation etching as needed.
[0052] There are no particular restrictions on the thickness of the base film, but from the viewpoint of strength, rigidity, etc., it is preferably 10 μm to 500 μm, more preferably 15 μm to 300 μm, and even more preferably 20 μm to 200 μm.
[0053] <Second Layer> The second layer is preferably a functional layer. Examples of functional layers include a release agent layer, an intermediate layer, a printing layer, a hard coat layer, an easy-adhesion layer, and an adhesive layer. The second layer preferably includes at least a release agent layer.
[0054] (Release Agent Layer) When the second layer is a release agent layer, it is preferable that the release agent layer is formed from a release agent composition. Having the second layer as a release agent layer makes it easy to remove the first layer at low water pressure (nozzle pressure P1). This ensures that the first and second layers can be removed sequentially at different water pressures and recovered separately. The release agent composition used to form the release agent layer is not particularly limited as long as it has release properties, and for example, release agent compositions mainly composed of silicone compounds; fluorine compounds; long-chain alkyl group-containing compounds; thermoplastic resin materials such as olefin resins and diene resins can be used. It is also preferable to use a release agent composition mainly composed of energy ray curable or thermosetting resins. These release agent compositions may be used individually or in combination of two or more.
[0055] In a release agent composition mainly composed of a silicone compound, the silicone compound may include a silicone compound having an organopolysiloxane as its basic structure. Other examples of the silicone compound include thermosetting silicone compounds such as addition reaction type and condensation reaction type; and energy ray curing silicone compounds such as ultraviolet curing type and electron beam curing type.
[0056] In a release agent composition mainly composed of a fluorine compound, examples of the fluorine compound include fluorosilicone compounds, fluoroboron compounds, and poly(perfluoroalkylene ether) chain-containing compounds.
[0057] In a release agent composition mainly composed of a long-chain alkyl group-containing compound, examples of the long-chain alkyl group-containing compound include polyvinyl carbamate obtained by reacting a long-chain alkyl isocyanate with a polyvinyl alcohol polymer, alkylurea derivatives obtained by reacting a long-chain alkyl isocyanate with polyethyleneimine, or copolymers of long-chain alkyl (meth)acrylates. Furthermore, a long-chain alkyl-modified alkyd resin obtained by a condensation reaction of a polyhydric alcohol and a polybasic acid, using a long-chain fatty acid as a modifying agent, may also be used.
[0058] Preferably, the release agent composition mainly composed of an energy-ray curable resin contains, for example, an energy-ray curable compound having a reactive functional group selected from a (meth)acryloyl group, an alkenyl group, and a maleimide group, and a polyorganosiloxane. In the release agent layer formed by this release agent composition, since the energy-ray curable compound and the polyorganosiloxane have different molecular structures, polarities, and molecular weights, components derived from the polyorganosiloxane segregate near the outer surface of the release agent layer before curing, and then the segregation is fixed by curing with energy rays. This improves the release properties of the release agent layer. The release agent composition mainly composed of an energy-ray curable resin may further contain a photopolymerization initiator.
[0059] Examples of release agent compositions mainly composed of thermosetting resins include release agent compositions mainly composed of melamine resin and release agent compositions mainly composed of epoxy resin. Examples of release agent compositions mainly composed of melamine resin include a composition containing melamine resin as the main component, an acid catalyst for thermosetting the melamine resin, and a polyorganosiloxane that imparts release properties to the release agent layer. Examples of release agent compositions mainly composed of epoxy resin include a composition containing epoxy resin as the main component, an acid or basic thermosetting catalyst for thermosetting the epoxy resin, and a polyorganosiloxane that imparts release properties to the release agent layer. Before curing, components derived from polyorganosiloxane segregate near the outer surface of the release agent layer, and then the segregation becomes fixed after curing. This improves the release properties of the release agent layer.
[0060] Furthermore, the release agent layer may contain other additives in addition to the resin components mentioned above. Examples of other additives include anti-aging agents, light stabilizers, flame retardants, conductive agents, antistatic agents, and plasticizers.
[0061] The thickness of the release agent layer can be selected as appropriate and is not particularly limited, but for example, it is preferably 0.02 μm or more and 5 μm or less, more preferably 0.03 μm or more and 2 μm or less, and even more preferably 0.05 μm or more and 1.5 μm or less.
[0062] (Intermediate layer) The second layer may include a release agent layer and an intermediate layer. In this case, the intermediate layer is placed between the base film and the release agent layer. Examples of the intermediate layer include a water-soluble intermediate layer, an alkali-degradable intermediate layer, and a layer that is hydrophilic and water-insoluble.
[0063] (Water-soluble intermediate layer) When the intermediate layer is a water-soluble intermediate layer, examples of water-soluble resins included in the intermediate layer include water-soluble polyvinyl alcohol resin, water-soluble acrylic resin, water-soluble polyester resin, water-soluble polyester urethane resin, water-soluble ethylene ionomer resin, water-soluble polyvinylpyrrolidone resin, water-soluble poly-N-vinylacetamide resin, water-soluble polyamide resin, water-soluble ethylene-vinyl alcohol resin, and water-soluble starch. The content of water-soluble resin in the intermediate layer is preferably 30% by mass or more and 90% by mass or less, and more preferably 40% by mass or more and 80% by mass or less, based on the total mass of the intermediate layer. The upper limit of the content of water-soluble resin in the intermediate layer is 100% by mass.
[0064] (Alkali-degradable intermediate layer) When the intermediate layer is an alkali-degradable intermediate layer, examples of alkali-degradable resins included in the intermediate layer include phenolic resin, polyacrylic acid, polyamide resin, polyester resin, and polylactic acid. The content of alkali-degradable resin in the intermediate layer is preferably 30% by mass or more and 90% by mass or less, and more preferably 40% by mass or more and 80% by mass or less, based on the total mass of the intermediate layer. The upper limit of the content of water-soluble resin in the intermediate layer is 100% by mass.
[0065] (Hydrophilic and water-insoluble layer) When the intermediate layer is a hydrophilic and water-insoluble layer, it is preferable that the intermediate layer is made of a silane compound that exhibits polycondensation by hydrolysis, from the viewpoint of more easily separating the second layer from the substrate film side surface of the intermediate layer. The silane compound is preferably a tetraalkoxysilane. More preferred specific examples of the tetraalkoxysilane include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetrabutoxysilane. Among these, from the viewpoint of ease of availability and reactivity of the hydrolysis reaction, it is preferable that it be at least one of tetramethoxysilane and tetraethoxysilane, or a mixture of tetramethoxysilane and tetraethoxysilane. Commercial products can also be used as the hydrolysis polycondensate of the silane compound.
[0066] When the intermediate layer contains a hydrophilic and water-insoluble resin (preferably the silane compound), the content of the hydrophilic and water-insoluble resin is preferably 30% to 90% by mass, and more preferably 40% to 80% by mass, relative to the total mass of the intermediate layer. The upper limit for the content of the hydrophilic and water-insoluble resin in the intermediate layer is 100% by mass.
[0067] The thickness of the intermediate layer is preferably 0.01 μm to 1 μm, more preferably 0.03 μm to 0.5 μm, and even more preferably 0.05 μm to 0.3 μm, from the viewpoint of facilitating moisture penetration when the intermediate layer comes into contact with water.
[0068] <First Layer> The first layer preferably includes a ceramic green sheet.
[0069] (Ceramic Green Sheet) A ceramic green sheet is obtained by coating the surface opposite to the second layer substrate film with a ceramic slurry, and then drying the ceramic slurry. Coating can be done using, for example, a slot die coating method or a doctor blade method. The ceramic slurry contains ceramic powder, a binder component, and a solvent. Examples of ceramic powder include dielectric powders such as barium titanate, titanium oxide, alumina, zirconia, zinc oxide, aluminum silicate, and silicon nitride. Examples of binder components include butyral resins and acrylic resins. Examples of solvents include organic solvents and aqueous solvents. When dielectric powder is used as the ceramic powder, a green sheet (specifically, a green sheet composed of dielectric as an active ingredient) used in the manufacture of multilayer ceramic capacitors (MLCCs) is obtained. The ceramic powder may be a ceramic powder other than a dielectric. The thickness of the ceramic green sheet is, for example, 0.1 μm or more and 10 μm or less.
[0070] (Conductive Layer) The first layer may include a ceramic green sheet and a conductive layer (specifically, a conductive layer composed of rare metals such as nickel, niobium, molybdenum, tantalum, and tungsten as active ingredients). In this case, the ceramic green sheet and the conductive layer are arranged in this order from the side of the second layer. The conductive layer is not particularly limited, and a conductive layer used in the manufacture of electronic components can be used. The conductive layer is formed on the surface of the ceramic green sheet opposite to the second layer, for example, by applying a conductive paste. The thickness of the conductive layer is, for example, 0.1 μm or more and 5 μm or less.
[0071] The laminated films used in each embodiment are generally used to protect the surfaces of other functional sheets and various components used for specific applications during manufacturing, transportation, and storage. After fulfilling their protective role, they are often peeled off the surface and discarded. Therefore, by using the laminated film, the coating layers (first and second layers) and the base film can be easily separated from the laminated film, making it a highly beneficial application from the standpoint of resource conservation and environmental protection.
[0072] 10... Feed-out shaft, 21... First backup roller, 22... Second backup roller, 31... First injection unit, 32... Second injection unit, 40... Winding shaft, 50... Water supply unit, 51... First supply pump, 52... Second supply pump, 53... First tank, 54... Piping, 55... Water source, 60... Water recovery and recycling device, 61, 62... Recovery pumps, 63... Second tank, 70... Residue removal device, 71... First detached material recovery unit, 72... Second detached material recovery unit, 75... Detection unit, 85... Nozzle Pressure control unit, 90, 90A...Laminated film, 91...Base film, 91a...First base surface, 91b...Second base surface, 92...Second layer, 93, 93A...First layer, 94, 94A...Coating layer, 100, 100A...Removal device, 301, 302...Injection chamber, 511, 521, 531, 532, 631, 632...Piping, 711, 721...Filtration filter, 712, 722...Storage section, 930...Recess, 1a, 2a...Discharge port, 21a, 22a...Central axis.
Claims
1. A method for removing a coating layer from a laminated film having a base film and two or more coating layers, wherein the two or more coating layers include at least a first layer and a second layer, and the second layer and the first layer are arranged in this order from the base film side toward the outermost layer side of the coating layer, and the method comprises: a first spraying step of spraying water onto the first layer of the laminated film with water pressure that removes the first layer of the laminated film and leaves the second layer of the laminated film; a second spraying step of spraying water onto the second layer of the laminated film with water pressure that removes the second layer remaining on the laminated film; and a base material recovery step of recovering the base film after the first and second layers have been removed from the laminated film.
2. The method for removing a coating layer according to claim 1, wherein the water pressure of the water sprayed onto the second layer is higher than the water pressure of the water sprayed onto the first layer.
3. A method for removing a coating layer according to claim 1 or claim 2, further comprising the steps of: preparing a laminated film roll in which the laminated film is wound in a roll shape; and unwinding the laminated film from the laminated film roll, wherein the substrate recovery step is a step of winding the substrate film into a roll shape and recovering it, and the preparation step, the unwinding step, the first spraying step, the second spraying step, and the substrate recovery step are performed in this order, and the steps from the unwinding step to the substrate recovery step are performed roll to roll.
4. The method for removing a coating layer according to claim 1 or claim 2, wherein the second layer includes a release agent layer.
5. The method for removing a coating layer according to claim 4, wherein the first layer includes a ceramic green sheet.
6. The method for removing a coating layer according to claim 4, wherein the first layer is a multilayer comprising a green sheet composed of a dielectric as an active ingredient and a conductive layer composed of a conductor as an active ingredient.
7. A method for removing a coating layer according to claim 1 or 2, comprising a first desorbent recovery step of filtering water containing the first desorbent, which is a first desorbent derived from the first layer that has been removed in the first injection step, to recover the first desorbent.
8. A method for removing a coating layer according to claim 3, comprising a step of detecting the presence or absence of the first or second layer after the first injection step and before the second injection step.
9. The method for removing a coating layer according to claim 8, wherein the detection step is a step of measuring the thickness of the laminated film in-line with a film thickness gauge.
10. A coating layer removal apparatus for removing a coating layer from a laminated film having a base film and two or more coating layers, wherein the two or more coating layers include at least a first layer and a second layer, and the second layer and the first layer are arranged in this order from the base film side toward the outermost layer side of the coating layer, and the apparatus includes: a feed shaft for feeding the laminated film from a laminated film roll in which the laminated film is wound in a roll shape; a first backup roller arranged downstream of the feed shaft for transporting the laminated film downstream; a first spray unit including one or more first nozzles arranged opposite the first backup roller, which sprays water from the first nozzles onto the first layer at a nozzle pressure P1 so as the laminated film passes the first backup roller to remove the first layer; and a second backup roller arranged downstream of the first spray unit for transporting the laminated film downstream. A coating layer removal device comprising: a second spraying unit that includes one or more second nozzles positioned opposite the second backup roller and sprays water from the second nozzles onto the second layer at a nozzle pressure P2 higher than the nozzle pressure P1 so as the laminated film passes the second backup roller to remove the second layer; a water supply unit that supplies water to the first spraying unit and the second spraying unit, respectively; and a winding shaft that winds the base film into a roll shape after the first and second layers have been removed from the laminated film, wherein the water supply unit includes one or more pumps, and the first spraying unit and the second spraying unit are connected to at least one of the one or more pumps.
11. The coating layer removal apparatus according to claim 10, further comprising a nozzle pressure control unit for controlling the nozzle pressure P1 and the nozzle pressure P2, wherein the nozzle pressure control unit is connected to the one or more pumps.
12. The coating layer removal apparatus according to claim 10 or claim 11, further comprising a first desorbent recovery unit for filtering water containing the first desorbent, which is a first desorbent derived from the first layer removed by the first injection unit, and recovering the first desorbent.
13. The coating layer removal apparatus according to claim 10 or claim 11, further comprising a detection unit for detecting the presence or absence of the first or second layer, located downstream of the first injection unit and upstream of the second injection unit.