Method for delaminating laminates
The method addresses partial layer retention in laminate delamination by using press-heating and peeling steps to weld and separate layers effectively, ensuring high purity and efficient reuse of materials.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- TOYOTA BOSHOKU KK
- Filing Date
- 2023-01-17
- Publication Date
- 2026-07-07
AI Technical Summary
Existing methods for delaminating laminates often result in partial retention of layers, leading to decreased purity and quality of recycled materials.
A method involving press-heating and peeling steps, where a laminate with specific thermoplastic resin layers is sandwiched between press plates and heated to melt and weld certain layers to other components, allowing for sequential peeling without partial retention.
The method ensures high purity of delaminated layers by preventing partial retention, enabling efficient reuse of laminate materials.
Smart Images
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Abstract
Description
[Technical Field]
[0001] This disclosure relates to a method for delaminating laminates. [Background technology]
[0002] Conventionally, the technique described in Patent Document 1 is known as a method for peeling laminates. Specifically, Patent Document 1 discloses a method for separating the surface layer and backing resin layer of a tile carpet by placing a tile carpet (laminated) on a conveyor belt, heating it in a heating furnace, and peeling off the surface layer end and the backing resin layer end of the tile carpet in opposite directions. [Prior art documents] [Patent Documents]
[0003] [Patent Document 1] Japanese Patent Publication No. 2010-69083 [Overview of the project] [Problems that the invention aims to solve]
[0004] However, in the method disclosed in Patent Document 1, it is possible that the backing resin layer may partially remain on the surface layer, or the surface layer may partially remain on the backing layer. In that case, the purity of the material of each layer obtained after separation will decrease, and the quality of the recycled product obtained by reusing each layer will decrease. Furthermore, when separating each layer by peeling it off from the laminate, it is desirable that one layer can be smoothly peeled off from the other.
[0005] This disclosure is a technology completed based on the circumstances described above, and one of its objectives is to provide a method for delaminating a laminate that can peel off each layer with high purity. Another objective is to provide a method for delaminating a laminate that can peel off each layer effectively. [Means for solving the problem]
[0006] This disclosure provides a method for peeling a laminate, comprising: a press-heating step of pressing a laminate, which comprises a first layer containing a first thermoplastic resin and a second layer containing a second thermoplastic resin having a higher melting point than the first thermoplastic resin and bonded to the first layer, between a pair of press plates and heating at a temperature above the melting point of the first thermoplastic resin and below the melting point of the second thermoplastic resin, thereby melting the first thermoplastic resin and welding the first layer to a member located on the opposite side from the second layer; and a peeling step of opening the pair of press plates and peeling the second layer from the first layer.
[0007] In this method of delaminating a laminate, during the press-heating process, the laminate is sandwiched between a pair of press plates and pressed and heated, causing the first thermoplastic resin of the first layer of the laminate to melt while the second thermoplastic resin of the second layer remains unmelted. The molten first thermoplastic resin then welds the first layer to a component located on the opposite side of the second layer (for example, a press plate in contact with the first layer, or a layer material placed between the press plate and the first layer), making it easier to delaminate the second layer from the first layer during the delamination process. This also suppresses the partial retention of the first layer on the delaminated second layer (or the partial retention of the second layer on the first layer), thereby increasing the purity of the materials in the first and second layers after delamination.
[0008] In the pressing and heating step, the laminate comprising a third layer containing a third thermoplastic resin with a lower melting point than the second thermoplastic resin and bonded to the side of the second layer opposite to the first layer, and a fourth layer containing a fourth thermoplastic resin with a higher melting point than the first and third thermoplastic resins and bonded to the side of the third layer opposite to the second layer, is heated at a temperature above the melting points of the first and third thermoplastic resins and below the melting points of the second and fourth thermoplastic resins to melt the third thermoplastic resin and weld the third layer to the second layer. In the peeling step, the pair of press plates may be opened, the fourth layer may be peeled off the third layer, and then the second layer may be peeled off the first layer.
[0009] In this method of delaminating a laminate, during the press-heating process, the first thermoplastic resin of the first layer and the third thermoplastic resin of the third layer of the laminate melt, while the second thermoplastic resin of the second layer and the thermoplastic resin of the fourth layer remain unmelted. The melted first and third thermoplastic resins then weld the first layer to the component located on the opposite side of the second layer, and weld the third layer to the second layer located on the opposite side of the fourth layer. This makes it possible to easily delaminate the fourth layer from the third layer, and then easily and sequentially delaminate the second layer from the first layer during the delamination process. By performing the press-heating process only once, the laminate can be separated into multiple layers during the delamination process, enabling smooth delamination. Furthermore, in the pressing and heating process, the fourth layer side of the third layer is more easily melted by the heat transmitted from the press plate than the second layer side (because the second and first layers are located on the second layer side), making it easier to peel the fourth layer from the third layer in the peeling process. This suppresses the partial retention of the third layer on the peeled fourth layer (or the partial retention of the fourth layer on the third layer), thereby increasing the purity of the materials in the third and fourth layers after peeling.
[0010] In the pressing and heating step, the laminate, which has the first layer having a higher basis weight than the second layer and is made of scraps of vehicle flooring material, may be sandwiched between the pair of press plates, pressed, and heated.
[0011] In order to suppress the transmission of vibrations such as sound into the vehicle's interior, the weight of the outer layer (first layer) of the vehicle's flooring material is sometimes made higher than that of the inner layer (e.g., second layer). With the lamination method described above, even scraps of such flooring material can be reused by effectively separating each layer.
[0012] In the pressing and heating step, the laminate, which has a flat portion and a curved portion that is bent relative to the flat portion, may be sandwiched between the pair of press plates, pressed, and heated so that the curved portion becomes flat relative to the flat portion.
[0013] According to such a method for peeling a laminate, even for a laminate having a bent portion, by performing a pressing and heating step, its shape can be formed flat, and the subsequent peeling step can be performed smoothly.
[0014] The method for peeling the laminate includes an arranging step that is performed before the pressing and heating step and arranges a plate-like body on the side of the first layer opposite to the second layer. In the pressing and heating step, the laminate and the plate-like body may be sandwiched between the pair of press plates, pressed, and heated to weld the first layer to the plate-like body arranged on the side opposite to the second layer.
[0015] According to such a method for peeling a laminate, in the pressing and heating step, the laminate and the plate-like body are sandwiched between the pair of press plates and pressed and heated, so that the first thermoplastic resin of the first layer in the laminate melts, and the second thermoplastic resin of the second layer is in a non-melted state. Then, by welding the first layer to the plate-like body with the melted first thermoplastic resin, in the peeling step, it becomes easier to peel the second layer from the first layer. And it can suppress that the first layer partially remains on the peeled second layer (or the second layer partially remains on the first layer), and can improve the purity of the materials of the first layer and the second layer after peeling.
[0016] In the peeling step, after peeling the second layer from the first layer, the plate-like body may be cooled to a temperature below the melting point of the first thermoplastic resin, and the first layer may be peeled from the plate-like body.
[0017] According to such a method for peeling a laminate, the first layer welded to the plate-like body can be cured, and the first layer can be peeled well from the plate-like body. Also, by performing this curing step after peeling the second layer from the first layer, the peeling of each layer can be performed smoothly.
[0018] In the arranging step, a metal plate may be arranged as the plate-like body.
[0019] According to such a method for peeling a laminate, in the pressing and heating step, the heat of the press plate is easily transferred to the first layer through the plate-like body. Then, the first layer is well welded to the plate-like body, and in the peeling step, the second layer is easily peeled from the first layer.
Advantages of the Invention
[0020] According to the present disclosure, it is possible to provide a method for peeling a laminate that can peel each layer with high purity. Further, it is possible to provide a method for peeling a laminate that can peel each layer well.
Brief Description of the Drawings
[0021] [Figure 1] Fig. showing the step of arranging the laminate according to Embodiment 1 on the plate-like body [Figure 2] Fig. showing the step of pressing and heating the laminate and the plate-like body sandwiched between a pair of press plates [Figure 3] Fig. showing the step of opening a pair of press plates [Figure 4] Fig. showing the step of peeling the fourth layer from the third layer [Figure 5] Fig. showing the step of peeling the second layer from the first layer [Figure 6] Fig. showing the step of transferring the plate-like body to the table and cooling it [Figure 7] Fig. showing the step of peeling the first layer from the plate-like body [Figure 8] Fig. showing the step of stacking the peeled layers and arranging them between a pair of press plates [Figure 9] Fig. showing the step of pressing and heating the peeled layers sandwiched between a pair of press plates [Figure 10] Fig. showing the step of opening a pair of press plates [Figure 11] Fig. showing the step of pressing and heating the laminate and the plate-like body according to Embodiment 2
Modes for Carrying Out the Invention
[0022] <Embodiment 1> Embodiment 1 of this disclosure will be described with reference to Figures 1 to 10. In this embodiment, a laminate 100 constituting the floor of an automobile (vehicle) and a method for peeling it off will be described. In each figure, the upper side is the surface side (inside the vehicle interior) of each member or layer, and the lower side is the back side (outside the vehicle interior) of each member or layer.
[0023] As shown in Figure 1, the laminate 100 is made from scraps of floor carpet (flooring material) laid on the sheet metal floor panels of an automobile. The laminate 100 is scrap material remaining after the floor carpet has been cut from a base material having the same cross-sectional configuration as the laminate 100. Such scrap material can take on various shapes (for example, flat, curved, irregularly shaped, etc.). Therefore, the shape of the laminate 100 is not particularly limited, but in this embodiment, a laminate 100 comprising a flat portion 100A and a curved portion 100B that is bent upward relative to the flat portion 100A is given as an example.
[0024] The laminate 100 comprises a first layer 10 containing a first thermoplastic resin, a second layer 20 containing a second thermoplastic resin having a higher melting point than the first thermoplastic resin and bonded to the surface of the first layer 10, a third layer 30 containing a third thermoplastic resin having a lower melting point than the second thermoplastic resin and bonded to the surface of the second layer 20 (the side of the second layer 20 opposite to the first layer 10), and a fourth layer 40 containing a fourth thermoplastic resin having a higher melting point than the first and third thermoplastic resins and bonded to the surface of the third layer 30 (the side of the third layer 30 opposite to the second layer 20).
[0025] The first layer 10 is a layer in the laminate 100 that is located on the floor panel side (exterior side of the passenger compartment) of the automobile and has the function of suitably absorbing vibrations such as sound (absorbing them better than the other layers 20, 30, and 40), and is sometimes called a backing layer. The first layer 10 is also a layer that adheres to the second layer 20. The second layer 20 has the function of absorbing vibrations that could not be absorbed by the first layer 10. The third layer 30 functions as an adhesive for bonding the second layer 20 and the fourth layer 40. The fourth layer 40 is a layer in the laminate 100 that is located on the interior side of the automobile and has the function of a surface layer. The fourth layer 40 makes it possible to improve the texture, feel, and design of the interior side surface of the laminate 100.
[0026] The materials used as the first thermoplastic resin, second thermoplastic resin, third thermoplastic resin, and fourth thermoplastic resin are not particularly limited, but for example, one or more thermoplastic resins such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and polylactic acid (PLA) can be used. In this embodiment, PE with a melting point of 125 degrees is used as the first thermoplastic resin and the third thermoplastic resin, and PET with a melting point of 260 degrees, which is higher than that of PE, is used as the second thermoplastic resin and the fourth thermoplastic resin. The first thermoplastic resin is the same material as the third thermoplastic resin, but it may be a different material. The second thermoplastic resin is the same material as the fourth thermoplastic resin, but it may be a different material.
[0027] The first layer 10 has a higher basis weight (mass per unit area) than the second layer 20. Furthermore, the first layer 10 may have a higher basis weight than the other layers 20, 30, and 40 (it may even be the layer with the highest basis weight in the laminate 100). The basis weight of the first layer 10 is 200 g / m². 2 More than 1000g / m 2 The following is also acceptable: 400g / m 2 More than 800g / m 2 The following is also acceptable: 500g / m 2 More than 700g / m 2The following may also be applicable. The basis weight of the second layer 20 may be higher than that of the third layer 30 and lower than that of the fourth layer 40. The basis weight of the second layer 20 may be 100 g / m 2 or more and 500 g / m 2 or less, may be 200 g / m 2 or more and 400 g / m 2 or less, may be 250 g / m 2 or more and 350 g / m 2 or less. The third layer 30 may have a lower basis weight compared to the other layers 10, 20, 40 (and may be the layer with the lowest basis weight in the laminate 100). The basis weight of the third layer 30 may be 10 g / m 2 or more and 200 g / m 2 or less, may be 50 g / m 2 or more and 150 g / m 2 or less, may be 80 g / m 2 or more and 120 g / m 2 or less. The basis weight of the fourth layer 40 may be 100 g / m 2 or more and 600 g / m 2 or less, may be 200 g / m 2 or more and 500 g / m 2 or less, may be 300 g / m 2 or more and 400 g / m 2 or less.
[0028] Subsequently, a method for peeling the laminate 100 will be described. The peeling method of the laminate 100 is roughly classified into an arrangement step of arranging the laminate 100 so that it is in contact with the surface of the plate-like body 50, and a pressing and heating step that is performed after the arrangement step and presses and heats the contact state of the laminate 100 and the plate-like body 50 between a pair of press plates 70, 71, and a peeling step that is performed after the pressing and heating step and peels the laminate 100 by opening the pair of press plates 70, 71.
[0029] As shown in Figure 1, in the arrangement process, the plate-like body 50 is placed on the back side of the first layer 10 (the side of the first layer 10 opposite to the second layer 20). At this time, the back surface of the flat portion 100A of the laminate 100 on the back surface of the first layer 10 is in contact with the plate-like body 50, while the back surface of the curved portion 100B of the laminate 100 on the back surface of the first layer 10 is floating away from the plate-like body 50. Then, the plate-like body 50 and the laminate 100 placed on the surface of the plate-like body 50 are placed on the surface of the lower press plate 70 of the pair of press plates 70, 71. The material of the plate-like body is not particularly limited, but for example, organic materials such as wood and resin, or inorganic materials such as glass and metal can be used. Among these, a metal plate made by forming metal into a plate is preferred as the material of the plate-like body, and an iron plate is more preferred.
[0030] Next, as shown in Figure 2, in the pressing and heating process, the laminate 100 and the plate-like body 50 are pressed and heated between a pair of press plates 70 and 71 while the laminate 100 remains in contact with the plate-like body 50. The pair of press plates 70 and 71 can sandwich the laminate 100 and the plate-like body 50 by bringing the upper press plate 71 close to the lower press plate 70. Then, by pressing and heating the laminate 100 between the pair of press plates 70 and 71, the curved portion 100B is formed to be flat relative to the flat portion 100A. As a result, the laminate 100 as a whole becomes a flat plate. The pressure applied by the pair of press plates 70 and 71 to the laminate 100 is not particularly limited, but for example, it can be a pressure greater than or equal to the pressure at which the curved portion 100B can be deformed to be flat relative to the flat portion 100A without heating.
[0031] Furthermore, in the pressing and heating process, the laminate 100 and the plate-like body 50 are heated by a pair of press plates 70 and 71 at a temperature above the melting point of the first thermoplastic resin and the third thermoplastic resin (the melting point of PE) and below the melting point of the second thermoplastic resin and the fourth thermoplastic resin (the melting point of PET), thereby melting the first thermoplastic resin and the third thermoplastic resin. If the materials of the first thermoplastic resin and the third thermoplastic resin are different, the lower limit of the heating temperature by the pair of press plates 70 and 71 shall be the higher of the melting points of the first thermoplastic resin and the third thermoplastic resin. If the materials of the second thermoplastic resin and the fourth thermoplastic resin are different, the upper limit of the heating temperature by the pair of press plates 70 and 71 shall be the lower of the melting points of the second thermoplastic resin and the fourth thermoplastic resin. In this embodiment, since the materials for the first thermoplastic resin and the third thermoplastic resin are PE, and the materials for the second thermoplastic resin and the fourth thermoplastic resin are PET, the heating temperature by the pair of press plates 70 and 71 may be, for example, 125 degrees Celsius or more and less than 260 degrees Celsius, 140 degrees Celsius or more and less than 200 degrees Celsius, or 150 degrees Celsius or more and less than 170 degrees Celsius.
[0032] By pressing and heating the laminate 100 with a pair of press plates 70 and 71, the third layer 30 is welded to the surface of the second layer 20, and the first layer 10 is welded to the surface of the plate-like body (a member located on the opposite side from the second layer) 50. The third layer 30 is easier to weld to the second layer 20 than the fourth layer 40. This is because, for example, there is more (or thicker) layer material between the third layer and the lower press plate 70 (second layer 20, first layer 10, and plate-like body) than the layer material between the third layer 30 and the upper press plate 71 (fourth layer 40), so the surface side of the third layer 30 is easier to heat and maintain a molten state than the back side, while the back side of the third layer 30 hardens relatively quickly even after melting, making it easier to weld to the second layer 20. Furthermore, the surface shape of the second layer 20 and the back surface shape of the fourth layer 40 can be appropriately modified (for example, by adding an uneven surface to the second layer 20) so that the bonding area (adhesion strength) between the third layer 30 and the second layer 20 is greater than the bonding area between the third layer 30 and the fourth layer 40. The first layer 10 is easier to weld to the plate-like body 50 than the second layer 20. This is because the first thermoplastic resin (PE) of the first layer 10 and the plate-like body 50 (iron plate) are a combination of materials that bond more easily than the first thermoplastic resin (PE) of the first layer 10 and the second thermoplastic resin (PET) of the second layer 20, and the bonding area between the first layer 10 and the plate-like body 50 is larger than the bonding area between the first layer 10 and the second layer 20.
[0033] Next, as shown in Figure 3, in the peeling process, the pair of press plates 70 and 71 are opened by separating the upper press plate 71 from the lower press plate 70, and the fourth layer 40 is peeled off from the third layer 30 as shown in Figure 4. At this time, the plate-like body 50 is placed on the lower press plate 70 and kept warm (the third thermoplastic resin may remain partially molten). Then, for example, an operator grasps the laminate 100 and the plate-like body 50 to fix them in place so that they do not move from the lower press plate 70, and peels off the fourth layer 40 using a peeling tool 90. The peeling tool 90 comprises a main body 91 and a plurality of needle-shaped scratching parts 92 extending from the main body 91, and the whole thing is brush-like. The operator peels off the fourth layer 40 from the third layer 30 by scratching the end 40A of the fourth layer 40 with the scratching parts 92 of the peeling tool 90, and separating it from the end 40A side relative to the third layer 30.
[0034] Next, as shown in Figure 5, the second layer 20 is peeled from the first layer 10 in the laminate 100 (the intermediate body 101 formed by peeling off the fourth layer 40 from the laminate 100). Specifically, while the plate-like body 50 remains on the lower press plate 70 to maintain heat (at this time, the first thermoplastic resin may remain partially melted), the end 20A of the second layer 20 is scratched with the scratching part 92 of the peeling tool 90, and the second layer 20 is peeled from the first layer 10 by separating it from the end 20A side relative to the first layer 10.
[0035] Subsequently, as shown in Figure 6, the plate-like body 50 to which the first layer 10 has been welded is placed on a cooling member 80, thereby cooling the plate-like body 50 to below the melting point of the first thermoplastic resin and hardening the first layer 10. The cooling member 80 is, for example, a table at room temperature (23 degrees Celsius), which allows the plate-like body 50 to be cooled to room temperature. Then, as shown in Figure 7, the edge 10A of the first layer 10 is scratched and grasped with the worker's fingernail or the like, and the first layer 10 is peeled away from the plate-like body 50 by separating it from the edge 10A side.
[0036] Next, the process for reusing the laminate 100 will be described. This reuse process, together with the method for peeling the laminate 100 described above, constitutes the method for reusing the laminate 100. First, after peeling the laminate 100, as shown in Figure 8, the peeled fourth layer 40 is placed on the lower press plate 70 as peeled fourth layer 41, the peeled second layer 20 is placed on the surface of peeled fourth layer 41 as peeled second layer 21, and a fourth layer 40 that has been peeled from another laminate 100 and is different from peeled fourth layer 41 is placed on the surface of peeled second layer 21 as peeled fourth layer 42 to form a superimposed body 102. Each peeled layer 41, 21, 42 may be irregular in size and shape, and adhesive portions 60, which are parts of the first layer 10 or third layer 30 that could not be completely peeled off, may be placed between each peeled layer 41, 21, 42.
[0037] Then, as shown in Figure 9, the upper press plate 71 is brought close to the lower press plate 70, and the superimposed material 102 is sandwiched between the pair of press plates 70 and 71 and pressed. Furthermore, the pair of press plates 70 and 71 heat the superimposed material 102 to a temperature above the melting points of the first and third thermoplastic resins and below the melting points of the second and fourth thermoplastic resins, thereby melting the adhesive portion 60 and bonding the release layers 41, 21, and 42. This forms a plate-shaped recycled material 103. The recycled material 103 can be removed by opening the pair of press plates 70 and 71. The obtained recycled material 103 can be reused as interior material for vehicles, such as flooring material for vehicles. Note that the type and number of release layers used to form the superimposed material 102 can be changed as appropriate.
[0038] Next, the effects of this embodiment will be described. In this embodiment, a method for peeling a laminate 100 is shown, which includes a pressing and heating step in which a laminate 100 comprising a first layer 10 containing a first thermoplastic resin and a second layer 20 containing a second thermoplastic resin having a higher melting point than the first thermoplastic resin and bonded to the first layer 10 is sandwiched between a pair of press plates 70, 71 and pressed, and heated at a temperature above the melting point of the first thermoplastic resin and below the melting point of the second thermoplastic resin to melt the first thermoplastic resin and weld the first layer 10 to a member 50 located on the opposite side from the second layer 20; and a peeling step in which the pair of press plates 70, 71 are opened and the second layer 20 is peeled off from the first layer 10.
[0039] According to this method of peeling the laminate 100, in the pressing and heating step, the laminate 100 is sandwiched between a pair of press plates 70, 71 and pressed and heated, causing the first thermoplastic resin of the first layer 10 of the laminate 100 to melt, while the second thermoplastic resin of the second layer 20 remains unmelted. The molten first thermoplastic resin then welds the first layer 10 to a component located on the opposite side of the second layer 20 (for example, a press plate in contact with the first layer 10, or a layer material located between the press plate and the first layer 10), making it easier to peel the second layer 20 from the first layer 10 in the peeling step. This suppresses the partial retention of the first layer 10 on the peeled second layer 20 (or the partial retention of the second layer 20 on the first layer 10), thereby increasing the purity of the materials of the first layer 10 and the second layer 20 after peeling.
[0040] In the press heating process, a laminate 100 comprising a third layer 30 containing a third thermoplastic resin with a lower melting point than the second thermoplastic resin and bonded to the side of the second layer 20 opposite to the first layer 10, and a fourth layer 40 containing a fourth thermoplastic resin with a higher melting point than the first and third thermoplastic resins and bonded to the side of the third layer 30 opposite to the second layer 20, is heated at a temperature above the melting points of the first and third thermoplastic resins but below the melting points of the second and fourth thermoplastic resins to melt the third thermoplastic resin and weld the third layer 30 to the second layer 20. In the peeling process, a pair of press plates 70, 71 are opened, the fourth layer 40 is peeled off the third layer 30, and then the second layer 20 is peeled off the first layer 10.
[0041] In this method of peeling the laminate 100, during the press-heating step, the first thermoplastic resin of the first layer 10 and the third thermoplastic resin of the third layer 30 of the laminate 100 melt, while the second thermoplastic resin of the second layer 20 and the thermoplastic resin of the fourth layer 40 remain unmelted. The melted first and third thermoplastic resins then weld the first layer 10 to the component located on the opposite side of the second layer 20, and weld the third layer 30 to the second layer 20 located on the opposite side of the fourth layer 40. This makes it possible to easily peel the fourth layer 40 from the third layer 30, and then easily peel the second layer 20 from the first layer 10 in sequence during the peeling step. By performing the press-heating step only once, the laminate 100 can be peeled into multiple layers during the peeling step, enabling smooth peeling. Furthermore, in the pressing and heating process, the fourth layer 40 side of the third layer 30 is more easily melted by the heat transmitted from the press plate than the second layer 20 side (because the second layer 20 and the first layer 10 are located on the second layer 20 side), making it easier to peel the fourth layer 40 from the third layer 30 in the peeling process. This suppresses the partial retention of the third layer 30 on the peeled fourth layer 40 (or the partial retention of the fourth layer 40 on the third layer 30), thereby increasing the purity of the materials of the third layer 30 and the fourth layer 40 after peeling.
[0042] In the pressing and heating process, a laminate 100 having a first layer 10 with a higher basis weight than the second layer 20, and made of scraps of vehicle flooring material, is sandwiched between a pair of press plates 70 and 71 and pressed and heated.
[0043] In order to suppress the transmission of vibrations such as sound into the vehicle's interior, the basis weight of the outer layer (first layer 10) of the vehicle's interior flooring material may be higher than that of the inner layer (for example, the second layer 20). With the above-described method for peeling the laminate 100, even scraps of such flooring material can be reused by effectively separating each layer.
[0044] In the pressing and heating process, the laminate 100, which has a flat portion 100A and a curved portion 100B that is bent relative to the flat portion 100A, is sandwiched between a pair of press plates 70 and 71, pressed, and heated to form the laminate so that the curved portion 100B becomes flat relative to the flat portion 100A.
[0045] According to this method of peeling the laminate 100, even if the laminate 100 has a curved portion 100B, the shape can be flattened by performing a pressing and heating process, making it possible to smoothly carry out the subsequent peeling process.
[0046] The method for peeling the laminate 100 described above is performed before the pressing and heating step, and includes an arrangement step in which a plate-shaped body 50 is placed on the side of the first layer 10 opposite to the second layer 20. In the pressing and heating step, the laminate 100 and the plate-shaped body 50 are sandwiched between a pair of press plates 70 and 71, pressed, and heated to weld the first layer 10 to the plate-shaped body 50 placed on the side of the second layer 20.
[0047] According to this method of peeling the laminate 100, in the pressing and heating step, the laminate 100 and the plate-like body 50 are sandwiched between a pair of press plates 70 and 71 and pressed and heated, causing the first thermoplastic resin of the first layer 10 of the laminate 100 to melt, while the second thermoplastic resin of the second layer 20 remains unmelted. The melted first thermoplastic resin then welds the first layer 10 to the plate-like body 50, making it easier to peel the second layer 20 from the first layer 10 in the peeling step. This suppresses the partial retention of the first layer 10 on the peeled second layer 20 (or the partial retention of the second layer 20 on the first layer 10), thereby increasing the purity of the materials of the first layer 10 and the second layer 20 after peeling.
[0048] In the peeling process, after peeling the second layer 20 from the first layer 10, the plate-like body 50 is cooled to below the melting point of the first thermoplastic resin, and the first layer 10 is peeled from the plate-like body 50.
[0049] This method for peeling the laminate 100 allows the first layer 10, which is welded to the plate-like body 50, to harden and be successfully peeled off from the plate-like body 50. Furthermore, by performing this hardening process after peeling off the second layer 20 from the first layer 10, the peeling of each layer can be carried out smoothly.
[0050] In the arrangement process, the metal plates are arranged as plate-shaped bodies 50.
[0051] With this method of peeling the laminate 100, the heat from the press plate 70 is easily transferred to the first layer 10 via the plate-like body 50 during the pressing and heating process. This allows the first layer 10 to be successfully welded to the plate-like body 50, making it easier for the second layer 20 to peel off from the first layer 10 during the peeling process.
[0052] <Embodiment 2> Next, Embodiment 2 of the present disclosure will be described with reference to Figure 11. In this embodiment, the same reference numerals are used for the same parts as in the above embodiment, and redundant explanations of the structure, operation, and effect are omitted. The laminate 200 comprises a first layer 10 and a second layer 20, and unlike the above embodiment, it does not comprise a third layer 30 and a fourth layer 40.
[0053] In the pressing and heating process, the laminate 200 and the plate-like body 50 are pressed and heated between a pair of press plates 70 and 71 while the laminate 200 remains in contact with the plate-like body 50. The pair of press plates 70 and 71 heat the laminate 200 and the plate-like body 50 to a temperature equal to or greater than that of the first thermoplastic resin but below the melting point of the second thermoplastic resin, thereby melting the first thermoplastic resin and welding the first layer 10 to the surface of the plate-like body (a member located on the opposite side from the second layer) 50. Next, in the peeling process, the second layer 20 is peeled from the first layer 10 of the laminate 200, and then the first layer 10 is peeled from the plate-like body 50.
[0054] <Other Embodiments> This disclosure is not limited to the embodiments described above and in the drawings. For example, the following embodiments are also included in the technical scope of this disclosure, and various modifications can be made without departing from the spirit of the disclosure.
[0055] (1) In the placement process, the laminate may be placed on the surface of the lower press plate, and the plate-like body may be placed on the surface of the laminate. In this case, the laminate is placed in an inverted position compared to the above embodiment (with the fourth layer in contact with the surface of the lower press plate).
[0056] (2) In the method for peeling the laminate, it is not necessary to use a plate-like body. For example, in the placement process, the laminate may be placed directly on the surface of the lower press plate, and only the laminate may be pressed and heated by a pair of press plates. In this case, the first layer of the laminate is welded to the lower press plate, which is positioned on the opposite side from the second layer.
[0057] (3) In the above embodiment, pressing and heating were performed by a pair of press plates, but the invention is not limited thereto. The pressing process and the heating process may be performed in separate processes (separate devices). For example, the laminate and the plate-like body may be placed on a conveyor and transported by the conveyor to a heater device, the laminate and the plate-like body may be heated by the heater device, then transported by the conveyor to a pair of press plates, and the heated laminate and plate-like body may be pressed by the pair of press plates.
[0058] (4) In the placement process, the orientation of the laminate placed on the plate-like body is not limited. For example, if the laminate is flat as a whole, the entire back surface (back surface of the first layer) of the laminate may be in surface contact with the plate-like body. Also, if the laminate is curved as a whole, only the corners at both ends of the laminate may be in line contact with the plate-like body, and the central part of the laminate may be floating above the plate-like body.
[0059] (5) In the above embodiment, the laminate was made from scraps of flooring material, but it is not limited to this. For example, the laminate may be the flooring material itself, or it may be a vehicle component other than flooring material (such as a base material for interior vehicle materials such as door trims, sound-absorbing material, or cushioning material).
[0060] (6) The method for peeling laminates illustrated in the above embodiments is not limited to laminates for vehicles, but may be applied to laminates used in various types of vehicles. For example, the method for peeling laminates can be applied to laminates used in vehicles such as trains and amusement vehicles as ground vehicles, airplanes and helicopters as flying vehicles, and ships and submarines as vehicles used on the sea or underwater. [Explanation of symbols]
[0061] 10...First layer, 20...Second layer, 30...Third layer, 40...Fourth layer, 50...Plate-like body, 70, 71...Pair of pressed plates, 100, 200...Laminate, 100A...Flat section, 100B...Curved section
Claims
1. A press heating step is performed by sandwiching a laminate comprising a first layer containing a first thermoplastic resin and a second layer containing a second thermoplastic resin having a higher melting point than the first thermoplastic resin and bonded to the first layer between a pair of press plates and pressing it, and heating it at a temperature above the melting point of the first thermoplastic resin and below the melting point of the second thermoplastic resin, thereby melting the first thermoplastic resin and welding the first layer to a member located on the opposite side from the second layer. A method for peeling a laminate, comprising a peeling step of opening the pair of press plates and peeling the second layer from the first layer.
2. In the pressing and heating step, the laminate comprising a third layer containing a third thermoplastic resin having a lower melting point than the second thermoplastic resin and bonded to the side of the second layer opposite to the first layer, and a fourth layer containing a fourth thermoplastic resin having a higher melting point than the first and third thermoplastic resins and bonded to the side of the third layer opposite to the second layer, is heated at a temperature above the melting points of the first and third thermoplastic resins but below the melting points of the second and fourth thermoplastic resins, thereby melting the third thermoplastic resin and welding the third layer to the second layer. The method for peeling a laminate according to claim 1, wherein in the peeling step, the pair of press plates are opened, the fourth layer is peeled off from the third layer, and then the second layer is peeled off from the first layer.
3. The method for peeling a laminate according to claim 1 or 2, wherein the laminate, which has a first layer with a higher basis weight than the second layer and is made of scraps of flooring material for vehicles, is sandwiched between the pair of press plates, pressed, and heated.
4. The method for peeling a laminate according to claim 1 or 2, wherein in the pressing and heating step, the laminate having a flat portion and a curved portion bent relative to the flat portion is sandwiched between a pair of press plates, pressed, and heated so that the curved portion becomes flat relative to the flat portion.
5. This step is performed before the pressing and heating step and includes an arrangement step in which a plate-shaped body is placed on the side of the first layer opposite to the second layer, The method for peeling a laminate according to claim 1 or 2, wherein in the pressing and heating step, the laminate and the plate-like body are sandwiched between the pair of press plates, pressed, and heated to weld the first layer to the plate-like body located on the opposite side from the second layer.
6. The method for peeling a laminate according to claim 5, wherein in the peeling step, after peeling the second layer from the first layer, the plate-like body is cooled to below the melting point of the first thermoplastic resin, and the first layer is peeled from the plate-like body.
7. The method for peeling a laminate according to claim 5, wherein in the arrangement step, the metal plate is arranged as the plate-like body.