Method for cleaning a carrier film and cleaning device

Abstract

The present invention provides a carrier film cleaning method and a carrier film cleaning device that are low in cost and environmental load in cleaning of a carrier film such as a PET film for recycling. The carrier film cleaning method of the present invention peels off a dielectric ceramic layer remaining on a surface of a carrier film by spraying water containing microbubbles on the surface of the carrier film. The carrier film cleaning device includes a holding section that holds a carrier film on which a dielectric ceramic layer remains, and a nozzle that peels off the dielectric ceramic layer remaining on a surface of the held carrier film by spraying water containing microbubbles on the surface of the carrier film.

Description

[0001] Related divisional application

[0002] This patent application is a divisional application of the invention patent application with application number 202410291180.7 entitled "Cleaning Method and Cleaning Apparatus for Carrier Membrane", the original application being filed on March 14, 2024. Technical Field

[0003] The embodiments relate to a method and apparatus for cleaning a carrier membrane. Background Technology

[0004] An industry publication describes a recycling system for reusing polyethylene terephthalate (PET) film used in the manufacturing process of multilayer ceramic capacitors. The recycling system cleans the surface of used, discarded PET film, restores it to PET resin (granular), forms a film, and performs special treatment on the film, thereby achieving reuse in the manufacturing process (Non-Patent Document 1).

[0005] [Existing technical documents]

[0006] [Patent Literature]

[0007] [Non-Patent Literature 1] Press Information: Title, Description, Keywords (TDK) for Recycling PET Film in Laminated Ceramic Capacitors (January 14, 2022) Summary of the Invention

[0008] [The problem the invention aims to solve]

[0009] The purpose of this embodiment is to provide a carrier membrane cleaning method and cleaning apparatus that has low cost and low environmental impact in the cleaning of carrier membranes such as PET membranes for recycling.

[0010] [Technical means to solve the problem]

[0011] The method for cleaning the carrier membrane according to the embodiment is characterized in that the residual dielectric ceramic layer is peeled off from the surface by spraying water containing microbubbles onto the surface of the carrier membrane on which the residual dielectric ceramic layer remains.

[0012] The carrier membrane cleaning apparatus of the embodiment is characterized by comprising: a holding section for holding the carrier membrane with residual dielectric ceramic layer; and a nozzle for peeling the residual dielectric ceramic layer from the surface by spraying water containing microbubbles onto the surface of the held carrier membrane.

[0013] [The effects of the invention]

[0014] Through the implementation of the embodiments, a carrier membrane cleaning method and cleaning apparatus with low cost and low environmental impact can be provided for cleaning the carrier membrane for recycling. Attached Figure Description

[0015] Figure 1 (a) is a planar conceptual diagram representing the carrier membrane to which the cleaning treatment is implemented. Figure 1 (b) is using Figure 1 Conceptual diagram of the cross section of line A-A' of (a).

[0016] Figure 2 (a) is a plan view illustrating the cleaning method and apparatus for the carrier membrane according to the embodiment. Figure 2 (b) is using Figure 2 Conceptual diagram of the cross section of line A-A' of (a).

[0017] Figure 3 It means in Figure 2 (b) is a cross-sectional concept diagram of the case in which the residual dielectric ceramic layer is peeled off from the surface by the spraying of water containing microbubbles.

[0018] Figure 4 This is a top view of a carrier membrane cleaning apparatus in an embodiment where the carrier membrane 101 is continuously cleaned.

[0019] Figure 5 This is a cross-sectional view of a carrier membrane cleaning apparatus in an embodiment where the carrier membrane 101 is continuously cleaned.

[0020] Figure 6 This is a cross-sectional conceptual diagram illustrating a carrier membrane cleaning method in an embodiment where the carrier membrane is continuously cleaned.

[0021] [Explanation of Symbols]

[0022] 1: Cleaning device

[0023] 11: Abutment

[0024] 12: Main body

[0025] 12a: Front surface

[0026] 12b: Back

[0027] 13: Side box

[0028] 14: Top Cover

[0029] 16: Entrance slit

[0030] 17: Side slit

[0031] 18a, 18b: Glass windows

[0032] 21: Inlet coil support

[0033] 22: Outgoing coil bracket

[0034] 28: Pump

[0035] 31: Sink

[0036] 32: Filter

[0037] 35, 35a~35e: Rollers

[0038] 36, 36a~36d: Nozzles

[0039] 36A: Water supply device

[0040] 37, 37a~37d: Scraper

[0041] 38: Pump

[0042] 39: Motor

[0043] 40: Control device

[0044] 100: Carrier membrane already used

[0045] 101: Carrier membrane

[0046] 101a: First Page

[0047] 101b: Second Page

[0048] 101c, 101d: Partial

[0049] 102: Dielectric ceramic layer

[0050] 105: Platform

[0051] 200: Water

[0052] 201: Water containing microbubbles

[0053] H: Stripping

[0054] P: Movement path Detailed Implementation

[0055] <Carrier Membrane>

[0056] First, the carrier membrane, which is the object of the cleaning process performed for recycling in this embodiment, will be described.

[0057] Figure 1(a) is a planar conceptual diagram showing the carrier membrane that is the object of the cleaning treatment in this embodiment. Figure 1 (b) is using Figure 1 Conceptual diagram of the cross section of line A-A' of (a).

[0058] like Figure 1 (a) and Figure 1 As shown in (b), in this embodiment, the carrier film 101, which is the object of the cleaning process for recycling, has a dielectric ceramic layer 102 formed in the manufacturing process of a multilayer ceramic capacitor with residues on its surface 101a.

[0059] The carrier film 101, on which a dielectric ceramic layer 102 remains on the surface 101a, is, for example, a strip-shaped film, which is wound into a coil shape during storage and transportation.

[0060] In addition, Figure 1 In (a), the remaining dielectric ceramic layer 102 is marked.

[0061] The carrier film 101, which includes the residual dielectric ceramic layer 102 on the surface 101a, is produced in the manufacturing process of a multilayer ceramic capacitor (a known method).

[0062] That is, the manufacturing process of a multilayer ceramic capacitor involves coating a dielectric ceramic material onto the surface 101a of a carrier film 101 and drying it, thereby forming a ceramic sheet (sometimes called a green sheet) on the surface 101a of the carrier film 101. Next, internal electrodes, for example, are printed onto the surface of the ceramic sheet using screen printing, and then it is dried in a drying oven or similar environment. Afterward, the ceramic sheet, including the internal electrodes, is peeled off from the carrier film 101 using a peeling device or similar method. Thus, as... Figure 1 (a) and Figure 1 A portion of the peeled ceramic sheet shown in (b) remains on the surface 101a of the carrier film 101 as a dielectric ceramic layer 102.

[0063] The carrier film 101 may contain, for example, polyethylene terephthalate (PET). The width or thickness of the carrier film 101 may be appropriately set by the manufacturing process of the laminated ceramic capacitor. The width of the carrier film 101 (the length of its short side if the carrier film 101 is a strip) may be, for example, 20 cm or more and 100 cm or less, and the thickness may be 15 μm or more and 250 μm or less.

[0064] In this embodiment, one side of the carrier film 101 is referred to as "first side 101a" and the other side is referred to as "second side 101b". Furthermore, the first side 101a, including the residual dielectric ceramic layer 102, is also referred to as "surface", and the first side 101a and the second side 101b are collectively referred to as "both sides".

[0065] The dielectric ceramic layer 102 remains on the first surface 101a of the carrier film 101, and is in a state of being fixed to the carrier film 101. As described above, the remaining dielectric ceramic layer 102 is a residue left on the surface 101a of the carrier film 101 after the ceramic sheet including the internal electrode is peeled off from the carrier film during the manufacturing process of the multilayer ceramic capacitor.

[0066] For example, before peeling the ceramic sheet including the internal electrode from the surface 101a of the carrier film 101, the ceramic sheet is uniformly formed over the entire area of ​​the surface 101a of the carrier film 101. When peeling the ceramic sheet including the internal electrode from the carrier film 101, for example, if a peeling device as shown in Japanese Patent Application Publication No. 2003-133159 is used, the remaining dielectric ceramic layer 102 has a ladder-like shape as follows ( Figure 1 (a) and Figure 1 The shape of (b) is such that the portion of the peeled ceramic sheet including the internal electrode becomes a recess, and in the recess, a portion of the peeled ceramic sheet remains on the surface 101a of the carrier film 101.

[0067] The material of the residual dielectric ceramic layer 102 is appropriately configured based on the material of the dielectric ceramic coated on the surface 101a of the carrier film 101 during the manufacturing process of the multilayer ceramic capacitor. The residual dielectric ceramic layer 102 is, for example, composed of a material with barium titanate as the main component and containing a bismuth compound as a secondary component and a reduction inhibitor for glass transition. The thickness of the residual dielectric ceramic layer 102 is, for example, 1 μm or more and 30 μm or less.

[0068] Furthermore, in the manufacturing process of a multilayer ceramic capacitor, ceramic sheets are formed on the first side 101a (surface) of the carrier film 101. However, in the manufacturing process of a multilayer ceramic capacitor, the carrier film 101, after the ceramic sheets have been peeled off, is continuously wound into a coil shape for recycling. Therefore, there are also cases where the remaining dielectric ceramic layer 102 adheres to the second side 101b (back side) of the carrier film 101 in the subsequent winding portion.

[0069] Next, the cleaning method and cleaning apparatus for the carrier membrane of this embodiment will be described.

[0070] Figure 2 (a) is a plan view illustrating the cleaning method and apparatus for the carrier membrane according to the embodiment. Figure 2 (b) is using Figure 2 Conceptual diagram of the cross section of line A-A' of (a).

[0071] like Figure 2 (a) and Figure 2As shown in (b), the method for cleaning the carrier film in this embodiment is to hold the carrier film 101, which includes the residual dielectric ceramic layer 102 on the surface 101a used in the manufacturing process of the multilayer ceramic capacitor, on the stage 105, for example, with the surface 101a as the upper surface, and spray water 201 containing microbubbles onto the surface 101a, thereby peeling off the residual dielectric ceramic layer 102 from the surface 101a.

[0072] Figure 3 It means in Figure 2 (b) is a cross-sectional concept diagram of the case in which the residual dielectric ceramic layer 102 is peeled off from the surface 101a by the spraying of water 201 containing microbubbles.

[0073] like Figure 2 (a) and Figure 2 (b) and Figure 3 As shown, water 201 containing microbubbles is sprayed onto the surface 101a of the carrier film 101 where the dielectric ceramic layer 102 remains, thereby peeling the remaining dielectric ceramic layer 102 off the surface 101a.

[0074] The mechanism for stripping H is believed to be as follows.

[0075] The reason is believed to be that water 201 containing microbubbles is sprayed onto the residual dielectric ceramic layer 102, but the microbubbles contained in the water break due to the force of the spray when they collide with the residual dielectric ceramic layer 102. The stress of the breakage coincides with the stress of the spray force, causing the residual dielectric ceramic layer 102 to peel off from the surface 101a.

[0076] As described above, the carrier membrane cleaning method of this embodiment can remove the residual dielectric ceramic layer 102 by spraying water 201 containing microbubbles, thus reducing cost and environmental impact.

[0077] Furthermore, in the case of peeling the entire residual dielectric ceramic layer 102 from the surface 101a of the carrier film 101, this can be done by moving a nozzle 36 (described below) that sprays water 201 containing microbubbles along, for example, the surface direction γ (the direction γ parallel to the surface 101a, the same below) α by an operator or by using a moving mechanism not shown.

[0078] In addition, jetting refers to blowing water containing microbubbles in a certain direction.

[0079] The jet can be a swaying jet. A swaying jet, as mentioned herein, refers to a jet in which the jet (containing water microbubbles) sways in a plane over time. Through this swaying jet, the wavy jet (containing water microbubbles) propagates radially from the nozzle 36.

[0080] As described above, by setting the jet from nozzle 36 to a swaying jet, the remaining dielectric ceramic layer 102 can be more easily peeled off.

[0081] Water 201 containing microbubbles is preferably sprayed onto surface 101a from the vertical direction β toward the surface direction γ at an angle θ.

[0082] Therefore, since the stress is applied at an angle θ relative to the remaining dielectric ceramic layer 102, it is easier to peel the remaining dielectric ceramic layer 102 off the surface 101a.

[0083] Angle θ is, for example, greater than 30° and less than 60°.

[0084] The nozzle 36 sprays water 201 containing microbubbles onto the first surface 101a of the carrier film 101 where the dielectric ceramic layer 102 remains (more preferably, a swirling spray, the same applies below). The nozzle 36 may be a pop-up nozzle, a cavitation nozzle, or a swirling nozzle.

[0085] The nozzle 36 is connected, for example, to a water supply device 36A. Water supplied from the water supply device 36A passes through the nozzle 36, generating water containing microbubbles, and is sprayed from the nozzle 36 onto the surface 101a of the carrier film 101 on which the dielectric ceramic layer 102 remains.

[0086] The term "water" as used here may appropriately refer to industrial water. Here, industrial water refers to surface water such as river water, lake water, dammed lake water, and reservoir water that is used to clarify raw water for industrial and clean water use through coagulation, filtration, etc. It also includes water supplied to businesses after simple coagulation and filtration at water purification plants, but does not include well water or spring water.

[0087] In addition, the "water" mentioned here can be well water, spring water, pure water, etc.

[0088] "Well water" refers to water from underground wells, including water that seeps out of the groundwater and remains in the well, as well as water that is injected into the well and remains there. It also refers to water that is pumped from the well into the degassing pipe by a vacuum pump.

[0089] "Spring water" refers to water that flows naturally from underground to the surface or into the surface.

[0090] "Pure water" refers to water with a resistivity of 0.1 MΩ·cm or higher.

[0091] The term "microbubble" as used here refers to bubbles with a diameter of less than 1 mm.

[0092] Microbubbles are generated in the water and supplied in a dispersed state. Nozzle 36 is used to generate microbubbles in the water, and the gas constituting the microbubbles is not particularly limited. For example, inert gases such as air, nitrogen, carbon dioxide, and rare gases, or oxidizing gases such as oxygen and ozone can be used as the gas constituting the microbubbles.

[0093] like Figure 2 (a) and Figure 2 As shown in (b), the carrier film cleaning apparatus of this embodiment includes: a holding part (stage 105) for holding a carrier film 101 used in the manufacturing process of a multilayer ceramic capacitor, on which a dielectric ceramic layer 102 remains on the surface 101a; and a nozzle 36 for peeling off the remaining dielectric ceramic layer 102 from the surface 101a by spraying water 201 containing microbubbles onto the surface 101a of the held carrier film 101.

[0094] The carrier membrane cleaning apparatus of this embodiment can use the above structure to peel off the residual dielectric ceramic layer 102 by spraying water 201 containing microbubbles, thus reducing cost and environmental impact.

[0095] When peeling the remaining dielectric ceramic layer 102 from the surface 101a, it is preferable to spray only water containing microbubbles onto the surface 101a of the carrier film 101 where the remaining dielectric ceramic layer 102 remains.

[0096] This results in lower costs and a lower environmental impact.

[0097] Next, a cleaning apparatus for continuously cleaning the carrier membrane for recirculation will be described.

[0098] Figure 4 This is a top view of a carrier membrane cleaning apparatus in an embodiment where the carrier membrane 101 is continuously cleaned.

[0099] Figure 5 This is a cross-sectional view of a carrier membrane cleaning apparatus in an embodiment where the carrier membrane 101 is continuously cleaned.

[0100] also, Figure 4 and Figure 5 For illustrative purposes, structural elements have been appropriately simplified and omitted. For example, in Figure 4 The top cover 14, as described below, is omitted in the text.

[0101] like Figure 4 and Figure 5 As shown, the carrier membrane cleaning apparatus 1 (hereinafter also referred to as "apparatus 1") of this embodiment includes a base 11, a main body 12, and a side box 13. The base 11, the main body 12, and the side box 13 are mostly made of, for example, stainless steel. The base 11 is a base that contacts the ground where the apparatus 1 is installed. The main body 12 and the side box 13 are disposed on the base 11.

[0102] The main body 12 is generally rectangular box-shaped and has a top cover 14. The top cover 14 can be opened and closed. When the top cover 14 is closed, the interior of the main body 12 becomes a generally watertight space. An inlet slit 16 is provided on the front surface 12a of the main body 12. An outlet slit 17 is provided on the back surface 12b of the main body 12. Glass windows 18a and 18b are embedded in the top cover 14. Side boxes 13 are disposed on the sides of the main body 12.

[0103] An inlet coil support 21 is installed below the inlet slit 16 in the front surface 12a of the main body 12. An outlet coil support 22 is installed below the outlet slit 17 in the back surface 12b of the main body 12. A used carrier film 100 (made by winding the carrier film 101 with the residual dielectric ceramic layer 102 into a coil shape) is assembled on the inlet coil support 21. The dielectric ceramic layer 102 is peeled off and removed by passing the used carrier film 100 through the device 1, leaving only the carrier film 101 wound into a coil shape on the outlet coil support 22. Hereinafter, in the description of the main body 12, when referred to as "carrier film 101", there may be a case where the used carrier film 100 with the residual dielectric ceramic layer 102 is included, in addition to the carrier film 101 that does not include the dielectric ceramic layer 102.

[0104] A water tank 31 is provided in the lower part of the interior of the main body 12. The upper surface of the water tank 31 is open. A filter 32 is disposed on the upper surface of the water tank 31. The water tank 31 collects and retains water containing microbubbles, which is sprayed onto the carrier membrane 101 to peel off the dielectric ceramic layer 102. The peeled dielectric ceramic layer 102 is then removed by the filter 32. The filter 32 is sprayed toward the carrier membrane 101, and the dielectric ceramic layer 102 is then separated from the peeled dielectric ceramic layer 102 and the water containing microbubbles. The filter 32 is, for example, a box-shaped structure made of stainless steel with an open upper surface, and a portion of the bottom surface contains perforated metal. A plurality of rollers 35a to 35e, a plurality of nozzles 36a to 36d, and a plurality of scrapers 37a to 37d are disposed in the upper part of the interior of the main body 12.

[0105] Multiple rollers 35a to 35e (hereinafter collectively referred to as "rollers 35") together with the inlet coil support 21 and the outlet coil support 22 constitute a moving mechanism (moving section) for moving the carrier film 101 from the inlet coil support 21 to the outlet coil support 22. The rollers 35 define the moving path P of the carrier film 101 within the main body 12. The rotation axis of each roller 35 extends along the left-right direction (paper direction) of the main body 12.

[0106] The number and configuration of rollers 35 are arbitrary; the following is a description of... Figure 4 and Figure 5 The example shown illustrates this.

[0107] Roller 35a is positioned above the back side of the inlet slit 16. Roller 35b is positioned below the back side of roller 35a. Roller 35c is positioned above the back side of roller 35b. Roller 35d is positioned on the back side of roller 35c. Roller 35e is positioned above the back side of roller 35d and above the front surface side of the outlet slit 17.

[0108] The movement path P of the carrier film 101 will be described. The carrier film 101 is wound out from the inlet coil holder 21, passes through the inlet slit 16, and passes through the upper side of roller 35a, the lower side of roller 35b, the upper side of roller 35c, the lower side of roller 35d, and the upper side of roller 35e, passes through the outlet slit 17, and is wound around the outlet coil holder 22. Furthermore, Figure 4 and Figure 5 An example is shown in which the carrier film 101 is moved from the input coil to the output coil in a manner of downward roll-out, but it is not limited to this, and it may also be downward roll-out, upward roll-out, or upward roll-out.

[0109] Water is supplied to nozzles 36a to 36d, and air is mixed into the water, thereby generating water 201 containing microbubbles. Nozzles 36a to 36d spray the water 201 containing microbubbles onto the first surface 101a and the second surface 101b of the carrier membrane 101.

[0110] Nozzles 36a to 36d (hereinafter collectively referred to as "nozzles 36") are disposed above and below rollers 35b and 35c in the travel path P of the carrier film 101. More specifically, nozzle 36a is disposed on the upper side of the travel path P. Nozzle 36b is disposed on the lower side of the travel path P. Nozzle 36c is disposed on the upper side of the travel path P and on the back side of nozzle 36a. Nozzle 36d is disposed on the lower side of the travel path P and on the back side of nozzle 36b.

[0111] Each of the nozzles 36a, 36b, 36c, and 36d has multiple nozzles, for example, six nozzles each, arranged at equal intervals along the width direction of the carrier membrane 101, i.e., the left-right direction of the main body 12. Therefore, a total of 24 nozzles 36 are provided. The direction in which water 201 is ejected from each nozzle 36 is inclined forward from the vertical direction. Thus, each nozzle 36 ejects water 201 containing microbubbles from the downstream side to the upstream side of the moving direction of the used carrier membrane 100.

[0112] Therefore, in a carrier membrane cleaning apparatus that continuously cleans the used carrier membrane 100, it is possible to implement an embodiment in which water containing microbubbles is sprayed onto the surface 101a from the vertical direction toward the surface direction in an angled manner.

[0113] The doctor blades 37a to 37d (hereinafter collectively referred to as "doctor blades 37") are disposed vertically in the portion between rollers 35d and 35e along the movement path P of the carrier film 101. More specifically, doctor blades 37a, 37b, 37c, and 37d are arranged sequentially from the front surface 12a of the main body 12 toward the back surface 12b. The edges of doctor blades 37a and 37c face upwards, while the edges of doctor blades 37b and 37d face downwards.

[0114] Thus, the carrier membrane 101 contacts the scraper 37 while passing over the upper sides of scrapers 37a and 37c, and the lower sides of scrapers 37b and 37d. In other words, scrapers 37a and 37c contact the second surface 101b of the carrier membrane 101 with their edges and move relative to the carrier membrane 101. Scrapers 37b and 37d contact the first surface 101a of the carrier membrane 101 with their edges and move relative to the carrier membrane 101. The scrapers 37 constitute a water removal mechanism for removing water containing microbubbles remaining on the first surface 101a and the second surface 101b (both surfaces) of the carrier membrane 101.

[0115] The glass windows 18a and 18b of the top cover 14 are positioned directly above the movement path P. Thus, the operator can visually identify the cleaning process of the carrier membrane 101 through the glass windows 18a and 18b, and can confirm whether the dielectric ceramic layer 102 has been removed from the carrier membrane 101, and whether water containing microbubbles has been removed from the carrier membrane 101.

[0116] A pump 38, a motor 39, and a control device 40 are installed inside the side chamber 13. The inlet of the pump 38 is connected to the water tank 31. The outlet of the pump 38 is connected to each nozzle 36. The pump 38 is supplied with water 200 from the water tank 31 and pressurized to supply the water to the nozzles 36. The water tank 31, the pump 38, and the filter 32 constitute a circulation mechanism that recovers the water 201 containing microbubbles sprayed onto the carrier membrane 101 and supplies the water 200 back to the nozzles 36.

[0117] The motor 39 is connected to the output coil support 22, the input coil support 21, and at least one roller 35 via a mechanical mechanism such as gears, and rotates these. The roller 35 not connected to the motor 39 is the driven roller. The motor 39, the output coil support 22, the input coil support 21, and the roller 35 connected to and rotating the motor 39 constitute the moving part of the carrier film 101.

[0118] The control device 40 controls the drive of the pump 38 and the motor 39. A control panel that can be operated by the operator can be installed in the control device 40.

[0119] The device 1 is equipped with a water supply pipe (not shown) for supplying water 200 from the outside. The water supply pipe is connected to the inlet of the pump 38 or the water tank 31. Thus, water 200 can be supplied to the device 1.

[0120] Next, the carrier membrane cleaning method of the embodiment in which the operation of the device 1 is carried out continuously will be described.

[0121] Figure 6 This is a cross-sectional conceptual diagram illustrating a carrier membrane cleaning method in an embodiment where the carrier membrane is continuously cleaned.

[0122] like Figure 4 and Figure 5 As shown, the used carrier film 100, wound into a coil shape, is assembled onto the inlet coil holder 21 of the device 1. Then, the top cover 14 of the main body 12 is opened, the used carrier film 100 is wound out of the coil and passed through the movement path P, and the front end is fixed to the outlet coil holder 22. Afterward, the top cover 14 is closed. Moreover, water 200 is pre-stored in the water tank 31 via a water supply pipe. Alternatively, the water supply pipe can be connected to a pump 38. The water 200 is, for example, industrial water.

[0123] Next, pump 38 is started. This pressurizes the water 200 supplied from the tank 31 or externally and supplies it to nozzle 36, where it mixes with air to generate water 201 containing microbubbles, which is then sprayed onto the used carrier membrane 100. Simultaneously, motor 39 is started. This causes the output coil support 22 and the like to rotate, and the used membrane 100 moves along the movement path P from the input coil towards the output coil.

[0124] like Figure 6As shown, water 201 containing microbubbles, sprayed from nozzles 36a and 36c, reaches the first surface 101a of the carrier membrane 101, and water 201 containing microbubbles, sprayed from nozzles 36b and 36d, reaches the second surface 101b of the carrier membrane 101. The water 201 containing microbubbles is sprayed from the downstream side toward the upstream side in the moving direction of the carrier membrane 101.

[0125] For example, water 201 containing microbubbles sprayed from nozzle 36a and water 201 containing microbubbles sprayed from nozzle 36b respectively reach the first surface 101a and the second surface 101b of portion 101c in carrier membrane 101, thus squeezing portion 101c from both sides. Furthermore, water 201 sprayed from nozzle 36c and water 201 containing microbubbles sprayed from nozzle 36d respectively reach the first surface 101a and the second surface 101b of portion 101d in carrier membrane 101, thus squeezing portion 101d from both sides. Portion 101d is located downstream of portion 101c, i.e., on the back surface 12b side of the main body 12.

[0126] After water 201 containing microbubbles enters the interface between the carrier membrane 101 and the dielectric ceramic layer 102, the dielectric ceramic layer 102 peels off from the carrier membrane 101. Thus, the dielectric ceramic layer 102 is removed from the used carrier membrane 100, leaving the carrier membrane 101 intact.

[0127] When water 201 containing microbubbles collides with the carrier membrane 101, most of the microbubbles disappear, restoring the water to its normal state. The water, along with fragments of the dielectric ceramic layer 102, falls from the carrier membrane 101 and reaches the filter 32. The detached dielectric ceramic layer 102 remains on the filter 32, and the water falls into the water tank 31 through the pores of the perforated metal of the filter 32. Thus, the water is separated from the dielectric ceramic layer 102. As described above, the water is recycled along the path (water tank 31 (water 200) → pump 38 → nozzle 36 → carrier membrane 101 → filter 32 → water tank 31).

[0128] like Figure 4 and Figure 5 As shown, the carrier membrane 101, with water adhering to it, passes through rollers 35c and 35d, and sequentially contacts the edges of scrapers 37a, 37b, 37c, and 37d. Water is removed from the second surface 101b of the carrier membrane 101 by scrapers 37a and 37c, and water is removed from the first surface 101a of the carrier membrane 101 by scrapers 37b and 37d. As described above, by contacting the scraper 37 with the first surface 101a and the second surface 101b of the carrier membrane 101, and by moving the scraper 37 relative to the carrier membrane 101, water is removed from the first surface 101a and the second surface 101b of the carrier membrane 101.

[0129] After the water is removed, the carrier membrane 101 passes through the outlet slit 17 and is discharged from the main body 12, and is wound in a coil shape onto the outlet coil support 22. As described above, the carrier membrane 101 is cleaned.

[0130] <Effect>

[0131] According to this embodiment, the dielectric ceramic layer 102 can be effectively removed from the used carrier membrane 100 by spraying water 201 containing microbubbles onto the used carrier membrane 100. As a result, the cost and environmental impact can be reduced in the cleaning of the carrier membrane for recycling.

[0132] Furthermore, by positioning the nozzles 36 on the upper and lower sides of the carrier membrane 101, water 201 containing microbubbles can collide with both the first surface 101a and the second surface 101b of the carrier membrane 101. Thus, regardless of which surface of the carrier membrane 101, the dielectric ceramic layer 102 remains, it can be removed. As a result, when assembling the coil-shaped used membrane 100 onto the inlet coil support 21, it is not necessary to confirm whether the surface with the residual dielectric ceramic layer 102 is the first surface 101a or the second surface 101b.

[0133] Furthermore, water 201 containing microbubbles collides with the same portion of the carrier membrane 101 from both sides. As a result, deformation of the carrier membrane 101 caused by water pressure can be suppressed, and the dielectric ceramic layer 102 can be removed efficiently.

[0134] Furthermore, in this embodiment, the carrier membrane 101 is moved along the moving path P, and water 201 containing microbubbles is sprayed from the downstream side to the upstream side of the moving direction of the carrier membrane 101 using the nozzle 36. Therefore, compared to the case where water 201 containing microbubbles is sprayed from the upstream side to the downstream side of the moving direction of the carrier membrane 101, it is easier for the water 201 containing microbubbles to reach the interface between the carrier membrane 101 and the dielectric ceramic layer 102, thereby increasing the effectiveness of removing the dielectric ceramic layer 102 from the carrier membrane 101.

[0135] Furthermore, as the carrier membrane 101 rises obliquely upwards from roller 35b toward roller 35c, water 201 containing microbubbles is sprayed upstream of the movement path P using nozzle 36. As a result, the water, having lost its microbubbles upon colliding with the carrier membrane 101, flows upstream of the movement path P due to the force of the spray and gravity, and falls off the carrier membrane 101 near roller 35b. Consequently, water can be prevented from moving directly to the scraper 37 while still attached to the carrier membrane 101.

[0136] Furthermore, in this embodiment, industrial water is used as the water source, and water 201 containing microbubbles is generated through nozzle 36. The water 200 is then reused via a circulation mechanism including a water tank 31, a pump 28, and a filter 32. Therefore, the cost of cleaning the carrier membrane 101 is reduced, and the environmental impact is also lower. Moreover, since the industrial water contains negative ions, it is possible to neutralize the positive ions in the dielectric ceramic layer 102. This also enhances the effectiveness of removing the dielectric ceramic layer 102 from the carrier membrane 101.

[0137] Furthermore, the possibility of cleaning the carrier membrane 101 by spraying water without microbubbles toward the used membrane 100 has been considered. However, in this method, the dielectric ceramic layer 102 cannot be efficiently peeled off from the carrier membrane 101. Increasing the water spray pressure has also been considered, but this would increase the size of the apparatus and the cost, and there is a possibility that the water pressure could damage the carrier membrane 101.

[0138] Furthermore, it is also considered to remove the dielectric ceramic layer 102 from the carrier film 101 by rubbing the used carrier film 100 with a cutting tool. However, in this case, the dielectric ceramic layer needs to be immersed in alcohol-diluted water. Therefore, the processing cost increases, and the used alcohol-diluted water needs to be discarded, increasing the environmental burden.

[0139] In contrast, according to this embodiment, a method and apparatus for cleaning carrier membranes with low cost and low environmental impact can be achieved.

[0140] The embodiments described above are examples of implementing the present invention, and the present invention is not limited to the described embodiments. For example, the results obtained by adding, deleting, or changing certain structural elements or processes in the embodiments described above are also included in the present invention.

[0141] The present invention includes the following forms.

[0142] (Note 1)

[0143] A method for cleaning a carrier membrane involves spraying water containing microbubbles onto the surface of the carrier membrane where a residual dielectric ceramic layer remains, thereby peeling the residual dielectric ceramic layer off the surface.

[0144] (Note 2)

[0145] The cleaning method for the carrier membrane as described in Note 1, wherein water containing microbubbles is sprayed onto the surface at an angle from a direction perpendicular to the surface.

[0146] (Note 3)

[0147] A carrier membrane cleaning apparatus includes: a holding section for holding a carrier membrane with a residual dielectric ceramic layer; and a nozzle for peeling the residual dielectric ceramic layer off the surface of the held carrier membrane by spraying water containing microbubbles onto the surface of the held carrier membrane.

[0148] (Note 4)

[0149] The carrier membrane cleaning apparatus as described in Note 3 further includes a moving part that moves the carrier membrane, and the nozzle sprays water containing microbubbles from the downstream side of the moving direction of the carrier membrane toward the upstream side.

[0150] (Note 5)

[0151] The carrier membrane cleaning apparatus as described in Note 4 further includes a scraper disposed downstream of the nozzle in the direction of movement of the carrier membrane, in contact with the surface of the carrier membrane, and moving relative to the carrier membrane.

Claims

1. A method for cleaning a carrier membrane, wherein water containing microbubbles is sprayed from the downstream side toward the upstream side of the carrier membrane in the direction of movement of the carrier membrane onto the surface of the carrier membrane, thereby peeling off the residual dielectric ceramic layer from the surface.

2. The method for cleaning the carrier membrane according to claim 1, wherein the carrier membrane comprises polyethylene terephthalate.

3. A cleaning apparatus for a carrier membrane, comprising: The holding section holds the carrier film with the residual dielectric ceramic layer; and A nozzle sprays water containing microbubbles from the downstream side of the carrier film toward the upstream side in the direction of movement of the carrier film onto the surface of the carrier film, thereby peeling off the residual dielectric ceramic layer from the surface.

4. The cleaning apparatus for the carrier membrane according to claim 3 further includes a scraper, the scraper being disposed downstream of the nozzle in the moving direction of the carrier membrane, contacting the surface of the carrier membrane, and moving relative to the carrier membrane.

5. The cleaning apparatus for the carrier membrane according to claim 4, wherein the carrier membrane comprises polyethylene terephthalate.

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