Sorting method and manufacturing method for recycled item

Abstract

To improve a quality of a product manufactured through recycling.SOLUTION: A sorting method according to one embodiment of the present invention includes: a separation step of separating a container wrapped with a wrap-around label from the wrap-around label; a crushing step of crushing the container into container pieces; and a removal step of removing the container pieces having an ink layer attached thereto from the plurality of container pieces. The container wrapped with the wrap-around label includes: the container; the wrap-around label having a substrate and the ink layer; a first adhesive layer for adhering one end of the wrap-around label to the container; and a second adhesive layer for adhering the other end of the wrap-around label to the substrate, wherein the first adhesive layer and the second adhesive layer are located on a side of the ink layer opposite to the substrate side, and at least a part of the ink layer remains attached to the first adhesive layer remaining on the container in a state after the wrap-around label is peeled off from the container.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a sorting method for sorting out container fragments that do not have an adhesive layer attached thereto from among a plurality of container fragments generated by crushing a container. [Background technology]

[0002] Conventionally, plastic products such as polyethylene terephthalate bottles (P1) have been widely used. From the viewpoint of resource conservation and environmental protection, there is a demand for the reuse of plastic products such as PET bottles.

[0003] Among plastic products, the recycling of PET bottles in particular has already become widespread. Meanwhile, plastic labels printed with product information and the like are sometimes attached to the body of PET bottles. Such labels include wrap-around labels, as disclosed in Patent Document 1, which are attached to PET bottles by adhering them to the bottle with an adhesive. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-3724 Summary of the Invention [Problem to be solved by the invention]

[0005] In the wrap-around label disclosed in Patent Document 1, when the wrap-around label is peeled off to recycle the PET bottle, adhesive remains on the PET bottle. Therefore, when the PET bottle is crushed into container fragments for recycling, some container fragments have adhesive attached and some do not. It is difficult to completely remove the adhesive attached to the container fragments, even during the cleaning process in the recycling process. Since adhesive is an impurity, if recycled resins such as PET resin are produced from these container fragments in a state where container fragments with adhesive attached are mixed, there is a problem that the quality of the recycled product will be reduced.

[0006] An object of one aspect of the present invention is to provide a sorting method and the like that can improve the quality of recycled products. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, a sorting method according to one embodiment of the present invention includes a separation step of peeling off the wrap-around label from a container around which the wrap-around label is wrapped, thereby separating the container from the wrap-around label; a crushing step of crushing the container from which the wrap-around label has been separated into container fragments; and a removal step of removing container fragments to which the ink layer is attached from the multiple container fragments produced by the crushing step, wherein the container around which the wrap-around label is wrapped includes the container, the wrap-around label having a substrate and the ink layer, a first adhesive layer that adheres one end of the wrap-around label to the container, and a second adhesive layer that adheres the other end of the wrap-around label to the substrate, and the first adhesive layer and the second adhesive layer are located on the opposite side of the ink layer from the substrate side, and after the wrap-around label is peeled off from the container, at least a portion of the ink layer remains attached to the first adhesive layer remaining on the container.

[0008] In order to solve the above-mentioned problems, one embodiment of the present invention provides a method for manufacturing recycled goods, which includes a separation step of peeling off the wrap-around label from a container around which the wrap-around label is wrapped, thereby separating the container from the wrap-around label; a crushing step of crushing the container from which the wrap-around label has been separated into container pieces; a removal step of removing the container pieces having the ink layer attached thereto from the multiple container pieces produced by the crushing step; and a step of manufacturing recycled goods using the container pieces remaining after the container pieces having the ink layer attached thereto have been removed as at least some of the materials, wherein the container around which the wrap-around label is wrapped includes the container, the wrap-around label having a substrate and the ink layer, a first adhesive layer that adheres one end of the wrap-around label to the container, and a second adhesive layer that adheres the other end of the wrap-around label to the substrate, and the first adhesive layer and the second adhesive layer are located on the opposite side of the ink layer from the substrate side, and after the wrap-around label is peeled off from the container, at least a portion of the ink layer remains attached to the first adhesive layer remaining on the container.

[0009] In order to solve the above-mentioned problems, a sorting method according to one aspect of the present invention includes a separation step of peeling off a wrap-around label from a container around which the wrap-around label is wrapped, to separate the container from the wrap-around label; a crushing step of crushing the container from which the wrap-around label has been separated into container fragments; and a removal step of removing container fragments to which the ink layer is attached from the plurality of container fragments produced by the crushing step, wherein the container around which the wrap-around label is wrapped includes the container, the wrap-around label having a substrate and the ink layer, and the wrap-around label. The wrap-around label includes a first adhesive layer that adheres one end of the wrap-around label to the container, and a third adhesive layer that adheres the other end of the wrap-around label to the container, wherein the first adhesive layer is provided only on the one end and the third adhesive layer is provided only on the other end, and the first adhesive layer and the third adhesive layer are located on the opposite side of the ink layer from the substrate side, so that after the wrap-around label is peeled off from the container, at least a portion of the ink layer remains attached to the first adhesive layer and the third adhesive layer that remain on the container.

[0010] In order to solve the above-mentioned problems, one aspect of the present invention provides a method for manufacturing recycled goods, comprising: a separation step of peeling off a wrap-around label from a container around which the wrap-around label is wrapped, and separating the container from the wrap-around label; a crushing step of crushing the container from which the wrap-around label has been separated into container fragments; a removal step of removing container fragments having the ink layer attached thereto from the plurality of container fragments produced by the crushing step; and a process of manufacturing recycled goods using, as at least a part of the material, the container fragments after the container fragments having the ink layer attached thereto have been removed, wherein the container around which the wrap-around label is wrapped is: The wrap-around label includes the container, the wrap-around label having a substrate and the ink layer, a first adhesive layer that adheres one end of the wrap-around label to the container, and a third adhesive layer that adheres the other end of the wrap-around label to the container, wherein the first adhesive layer is provided only on the one end and the third adhesive layer is provided only on the other end, and the first adhesive layer and the third adhesive layer are located on the opposite side of the ink layer from the substrate side, and after the wrap-around label is peeled off from the container, at least a portion of the ink layer remains attached to the first adhesive layer and the third adhesive layer that remain on the container. [Effects of the Invention]

[0011] According to one aspect of the present invention, the quality of recycled products can be improved. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a front view of a PET bottle container according to a first embodiment of the present invention. [Figure 2] FIG. 3 is a cross-sectional view showing the configuration of the wrap-around label before being wrapped around the PET bottle container. [Figure 3] FIG. 2 is an enlarged cross-sectional view of the PET bottle container, showing the area around the wrap-around label that is adhered to the body of the container. [Figure 4]FIG. 2 is an enlarged cross-sectional view showing the area where the first adhesive layer was adhered to the PET bottle container after the wrap-around label has been peeled off from the PET bottle container. [Figure 5] 3 is a flowchart showing an example of the process of the PET bottle container recycling method. [Figure 6] FIG. 10 is a cross-sectional view showing the configuration of a wrap-around label according to a second embodiment of the present invention before being wrapped around a PET bottle container. [Figure 7] FIG. 2 is an enlarged cross-sectional view of the PET bottle container, showing the area around where the wrap-around label A is adhered to the body of the container. [Figure 8] FIG. 2 is an enlarged cross-sectional view showing the area where the first adhesive layer and the third adhesive layer were adhered on the PET bottle container after the wrap-around label has been peeled off from the PET bottle container. [Figure 9] FIG. 10 is a cross-sectional view showing the configuration of a wrap-around label according to a third embodiment of the present invention before being wrapped around a PET bottle container. [Figure 10] FIG. 2 is an enlarged cross-sectional view of the PET bottle container, showing the area around the wrap-around label that is adhered to the body of the container. [Figure 11] FIG. 2 is an enlarged cross-sectional view showing the area where the first adhesive layer of the PET bottle container was adhered after the PET bottle container was treated with an alkaline solution. [Figure 12] FIG. 10 is a cross-sectional view showing the structure of a wrap-around label according to a fourth embodiment of the present invention before being wrapped around a PET bottle container. [Figure 13] FIG. 2 is an enlarged cross-sectional view of the PET bottle container, showing the area around the wrap-around label that is adhered to the body of the container. [Figure 14] FIG. 2 is an enlarged cross-sectional view showing the area where the first adhesive layer was adhered to the PET bottle container after the wrap-around label was physically peeled off from the PET bottle container. [Figure 15] FIG. 10 is a cross-sectional view showing the structure of a wrap-around label 10D before being wrapped around a PET bottle container 1 according to a fifth embodiment of the present invention. [Figure 16] FIG. 2 is an enlarged cross-sectional view of the PET bottle container, showing the area around the wrap-around label that is adhered to the body of the container. [Figure 17] It is an enlarged cross-sectional view showing the regions where the first adhesive layer and the third adhesive layer of the PET bottle container were adhered after peeling off the wrapped label from the PET bottle container. [Figure 18] It is a cross-sectional view showing the structure of the wrapped label 10E before being wrapped around the PET bottle container 1 according to Embodiment 6 of the present invention. [Figure 19] It is an enlarged cross-sectional view of the periphery of the region where the wrapped label is adhered to the body of the PET bottle container. [Figure 20] It is an enlarged cross-sectional view showing the region where the first adhesive layer of the PET bottle container was adhered after physically peeling off the wrapped label from the PET bottle container. [Figure 21] It is a cross-sectional view showing the structure of the wrapped label before being wrapped around the PET bottle container according to Embodiment 7 of the present invention. [Figure 22] It is an enlarged cross-sectional view of the periphery of the region where the wrapped label is adhered to the body of the PET bottle container. [Figure 23] It is an enlarged cross-sectional view showing the regions where the first adhesive layer and the third adhesive layer of the PET bottle container were adhered after peeling off the wrapped label from the PET bottle container.

Mode for Carrying Out the Invention

[0013] 〔Embodiment 1〕 Hereinafter, an embodiment of the present invention will be described in detail.

[0014] <PET bottle container 1> FIG. 1 is a front view of the PET bottle container 1 in the present embodiment. As shown in FIG. 1, the PET bottle container 1 includes a container body 2 and a wrapped label 10.

[0015] The container body 2 is made of polyethylene terephthalate. The container body 2 has a container body part 3. The wrapped label 10 is wrapped around the container body part 3.

[0016] Fig. 2 is a cross-sectional view showing the configuration of the wrap-around label 10 before it is wrapped around the PET bottle container 1. Fig. 3 is an enlarged cross-sectional view of the PET bottle container 1 around the area where the wrap-around label 10 is adhered to the container body 3.

[0017] As shown in FIGS. 2 and 3, the wrap-around label 10 has a substrate 11, an ink layer 12, a first adhesive layer 13, and a second adhesive layer 14.

[0018] The substrate 11 can be made of a conventional material, such as a biaxially oriented film of a synthetic resin, such as a polyester resin (e.g., polyethylene terephthalate), an olefin resin (e.g., polypropylene), or a styrene resin; a laminated film of a synthetic resin film; paper, Japanese paper, synthetic paper, a foamed resin sheet, a nonwoven fabric, or a laminated film of these. In particular, when the wrap-around label 10 is used on a polyethylene terephthalate container (PET bottle), polypropylene film is preferred from the viewpoint of ease of attachment and specific gravity difference during recycling, with a film thickness of 20 to 60 μm being preferred. Furthermore, when the wrap-around label 10 is used on a PET bottle, polyester film is preferred from the viewpoint of recycling the label itself, with a film thickness of 10 to 50 μm being preferred.

[0019] The ink layer 12 is a layer on which a predetermined design, such as a product name or a picture, is printed using ink. The ink layer 12 is formed using water-based ink or oil-based ink. Conventional inks used for label printing and the like can be used as the water-based ink or oil-based ink forming the ink layer 12. Oil-based inks may be used that contain additives in a colorant such as a pigment or dye, a binder resin such as an acrylic resin, a urethane resin, a polyester resin, or a polyamide resin, and an organic solvent. Water-based inks may also be used that contain a colorant, a water-soluble or water-dispersible binder resin, additives, etc. Examples of additives include lubricants, anti-blocking agents, and anti-settling agents.

[0020] The first adhesive layer 13 and the second adhesive layer 14 are adhesive layers that bond the ends of the wrap-around label 10 in order to wrap the wrap-around label 10 around the PET bottle container 1. As shown in FIG. 2, the first adhesive layer 13 and the second adhesive layer 14 are located on the opposite side of the ink layer 12 from the substrate 11 side.

[0021] The first adhesive layer 13 and the second adhesive layer 14 may be made of, for example, a heat-sensitive adhesive that does not exhibit adhesiveness at room temperature but exhibits adhesiveness when heated. Examples of such heat-sensitive adhesives that can be used include hot-melt adhesives, part-coat heat-sensitive adhesives, and delayed-tack heat-sensitive adhesives. The adhesives used for the first adhesive layer 13 and the second adhesive layer 14 may be pressure-sensitive adhesives in addition to heat-sensitive adhesives. The first adhesive layer 13 and the second adhesive layer 14 may be made of different adhesives.

[0022] 3, the first adhesive layer 13 adheres one end 10a of the wrap-around label 10, more specifically, one end of the ink layer 12, to the container body 3. The second adhesive layer 14 adheres the other end 10b of the wrap-around label 10, more specifically, the other end of the ink layer 12, in the area where the first adhesive layer 13 adheres one end 10a of the wrap-around label 10. This results in the wrap-around label 10 being wrapped around and attached to the container body 3.

[0023] In the PET bottle container 1 of this embodiment, the adhesion strength between the ink layer 12 and the first adhesive layer 13 is greater than the adhesion strength between the ink layer 12 and the substrate 11. The adhesion strength between the ink layer 12 and the first adhesive layer 13 and the adhesion strength between the ink layer 12 and the substrate 11 can be set by appropriately combining the materials that make up the substrate 11, the ink layer 12, and the first adhesive layer 13.

[0024] The adhesion strength can be compared, for example, as follows: After forming an ink layer 12 on a substrate 11, the ink layer 12 and a PET sheet are bonded together with a first adhesive layer 13. The bonded portions are then peeled off in a 180-degree direction, and the peeled interlayer is the interlayer having a weaker adhesion strength than the other interlayer.

[0025] 4 is an enlarged cross-sectional view showing the area of ​​the PET bottle container 1 where the first adhesive layer 13 was adhered after the wrap-around label 10 has been physically (for example, manually) peeled off from the PET bottle container 1. As described above, the adhesion between the ink layer 12 and the first adhesive layer 13 is greater than the adhesion between the ink layer 12 and the substrate 11. Therefore, when the wrap-around label 10 is physically peeled off from the PET bottle container 1, the wrap-around label 10 separates between the ink layer 12 and the substrate 11, not between the ink layer 12 and the first adhesive layer 13. As a result, as shown in FIG. 4, after the wrap-around label 10 has been peeled off from the PET bottle container 1, the first adhesive layer 13 remains on the PET bottle container 1, and the ink layer 12 remains attached to the first adhesive layer 13.

[0026] In the PET bottle container 1 of this embodiment, the ink layer 12 and the substrate 11 are in contact with each other, but the PET bottle container 1 of the present invention is not limited to this. For example, another layer may be included between the ink layer 12 and the substrate 11. In this case, the PET bottle container is configured so that the adhesion between the ink layer 12 and the first adhesive layer 13 is greater than the adhesion between the ink layer 12 and the layer located on the substrate 11 side of the ink layer 12 (the other layer). Furthermore, the ink layer 12 does not have to be provided between the second adhesive layer 14 and the substrate 11. In other words, the second adhesive layer 14 may be provided so as to be in direct contact with the substrate 11. This configuration also applies to Embodiments 3, 4, and 6 described below.

[0027] <Recycling method> Next, a method for recycling PET bottle containers 1 in this embodiment will be described. Fig. 5 is a flowchart showing an example of the process of the method for recycling PET bottle containers 1 in this embodiment. In the method for recycling PET bottle containers 1 in this embodiment, as shown in Fig. 5, first, the wrap-around label 10 is separated from the PET bottle container 1 (step S1, separation step). In the separation step S1 of this embodiment, the wrap-around label 10 is physically separated from the PET bottle container 1. This leaves the ink layer 12 attached to the first adhesive layer 13 remaining on the PET bottle container 1, as shown in Fig. 4.

[0028] Next, the PET bottle container 1 from which the wrap-around label 10 has been peeled off is crushed into a plurality of container pieces (step S2, crushing step). In the crushing step S2, the PET bottle container 1 is crushed into container pieces using, for example, a conventional crusher.

[0029] Here, the multiple container fragments generated by the crushing step S2 include container fragments with the first adhesive layer 13 attached and container fragments without the first adhesive layer 13 attached. When recycling PET bottle containers, if container fragments with an adhesive layer attached are included as part of the material, the adhesive layer becomes an impurity, which reduces the quality of the PET bottle containers produced by recycling. Therefore, it is preferable to exclude the container fragments with an adhesive layer attached and use only the container fragments without an adhesive layer attached as material.

[0030] Therefore, in this embodiment, a removal step S3 is performed after the crushing step S2, in which container fragments having the first adhesive layer 13 attached thereto are removed from the plurality of container fragments produced by the crushing step S2. In the removal step S3, container fragments having the ink layer 12 attached thereto are removed from the plurality of container fragments produced by the crushing step S2. In the removal step S3, for example, the container fragments may be arranged so that they do not overlap each other, a color sensor may be used to identify the container fragments having the ink layer 12 attached thereto, and an air nozzle may be used to blow air toward the identified container fragments to blow them away, thereby removing the container fragments having the ink layer 12 attached thereto. From the viewpoint of improving the accuracy of container fragment sorting using a color sensor or the like, it is preferable that the ink layer 12 located on the first adhesive layer 13 is a color different from that of the container body 2, and in particular, it is preferable that the color be a color that is easily distinguishable by a color sensor or the like.

[0031] In this way, in the removing step S3, container fragments having the ink layer 12 attached thereto are removed from the plurality of container fragments produced in the crushing step S2. This makes it possible to remove container fragments having the first adhesive layer 13 attached thereto from the plurality of container fragments produced in the crushing step S2. The separating step S1, crushing step S2, and removing step S3 are a sorting method for selecting container fragments having no first adhesive layer 13 attached thereto from the plurality of container fragments produced by crushing the PET bottle container 1.

[0032] Next, the container pieces from which the container pieces to which the first adhesive layer 13 is attached are removed are used at least as part of the material to manufacture PET bottle containers (container manufacturing process, step S4). Known techniques can be used in the container manufacturing process S4. Note that, in this embodiment, an embodiment in which PET bottle containers are manufactured by recycling has been described, but the container pieces from which the container pieces to which the first adhesive layer 13 is attached are removed may also be used at least as part of the material to manufacture items other than PET bottle containers. For example, resin pellets, resin fluff, etc. may be manufactured as materials for plastic products.

[0033] As described above, the PET bottle container 1 in this embodiment is wrapped with a wrap-around label 10 in which the adhesion between the ink layer 12 and the first adhesive layer 13 is greater than the adhesion between the ink layer 12 and the substrate 11. As a result, after the wrap-around label 10 is peeled off from the PET bottle container 1, the ink layer 12 remains attached to the first adhesive layer 13 remaining on the PET bottle container 1. Therefore, when the PET bottle container 1 is crushed into container fragments for recycling, it is possible to identify the container fragments to which the first adhesive layer 13 is attached. This makes it possible to selectively remove container fragments to which the first adhesive layer 13 is attached, thereby improving the quality of recycled products. Furthermore, in the PET bottle container 1, the ink layer 12 always adheres to the first adhesive layer 13 remaining on the PET bottle container 1, making it possible to reliably identify the container fragments to which the first adhesive layer 13 is attached.

[0034] It should be noted that the article to which the wrap-around label 10 is attached is not limited to the PET bottle container 1. The article may be any container other than a PET bottle as long as it is used with the wrap-around label 10 attached. Furthermore, according to this embodiment, it is possible to improve the recycling rate of PET bottle containers 1, thereby contributing to the achievement of the Sustainable Development Goals (SDGs).

[0035] [Embodiment 2] Other embodiments of the present invention will be described below. For ease of explanation, the same reference numerals will be used to designate components having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

[0036] Fig. 6 is a cross-sectional view showing the configuration of the wrap-around label 10A before it is wrapped around the PET bottle container 1 in this embodiment. Fig. 7 is an enlarged cross-sectional view of the PET bottle container 1 around the area where the wrap-around label 10A is adhered to the container body 3.

[0037] 6 and 7, the wrap-around label 10A has a third adhesive layer 15 instead of the second adhesive layer 14 of the wrap-around label 10 in embodiment 1. The third adhesive layer 15 is made of the same material as the first adhesive layer 13.

[0038] 7, the first adhesive layer 13 adheres one end 10Aa of the wrap-around label 10A, more specifically, one end of the ink layer 12, to the container body 3. The second adhesive layer 14 adheres the other end 10Ab of the wrap-around label 10A, more specifically, the other end of the ink layer 12, to the container body 3 in an area adjacent to the area to which the first adhesive layer 13 adheres the one end 10Aa of the wrap-around label 10A. This results in the wrap-around label 10A being wrapped around and attached to the container body 3.

[0039] In the PET bottle container 1 of this embodiment, as in the PET bottle container 1 of embodiment 1, the adhesion force between the ink layer 12 and the first adhesive layer 13 is greater than the adhesion force between the ink layer 12 and the substrate 11, and the adhesion force between the ink layer 12 and the third adhesive layer 15 is greater than the adhesion force between the ink layer 12 and the substrate 11.

[0040] FIG. 8 is an enlarged cross-sectional view showing the area of ​​the PET bottle container 1 where the first adhesive layer 13 and the third adhesive layer 15 were adhered after the wrap-around label 10A was physically peeled off from the PET bottle container 1. As described above, the adhesion strength between the ink layer 12 and the first adhesive layer 13 and the adhesion strength between the ink layer 12 and the third adhesive layer 15 are greater than the adhesion strength between the ink layer 12 and the substrate 11. Therefore, when the wrap-around label 10A is physically peeled off from the PET bottle container 1, the wrap-around label 10A separates between the ink layer 12 and the substrate 11. As a result, as shown in FIG. 8, after the wrap-around label 10A has been peeled off from the PET bottle container 1, the ink layer 12 remains attached to the first adhesive layer 13 and the third adhesive layer 15 remaining on the PET bottle container 1. Therefore, when the PET bottle container 1 is crushed into container fragments for recycling, it is possible to identify the container fragments to which the first adhesive layer 13 or the third adhesive layer 15 is adhered. Therefore, it becomes possible to selectively remove container pieces to which the first adhesive layer 13 or the third adhesive layer 15 is attached, thereby improving the quality of the recycled products.

[0041] [Embodiment 3] Another embodiment of the present invention will be described below. Fig. 9 is a cross-sectional view showing the configuration of a wrap-around label 10B before being wrapped around a PET bottle container 1 in this embodiment. Fig. 10 is an enlarged cross-sectional view of the PET bottle container 1 around the area where the wrap-around label 10B is adhered to the container body 3.

[0042] 9 and 10, the wrap-around label 10B has an alkali-soluble layer 16 in addition to the configuration of the wrap-around label 10 in embodiment 1. As shown in Fig. 9 and 10, the alkali-soluble layer 16 is a layer located between the ink layer 12 and the substrate 11. The alkali-soluble layer 16 is alkali-soluble.

[0043] As shown in Figure 10, in the PET bottle container 1 of this embodiment, similar to the PET bottle container 1 of embodiment 1, one end 10Ba of the wrap-around label 10B is adhered to the container body 3 by a first adhesive layer 13, and the other end 10Bb of the wrap-around label 10B is adhered to the base material 11 by a second adhesive layer 14.

[0044] 11 is an enlarged cross-sectional view showing the area of ​​the PET bottle container 1 where the first adhesive layer 13 was adhered after the PET bottle container 1 has been treated with an alkaline solution (for example, immersed in an alkaline solution). The PET bottle container 1 in this embodiment has an alkali-soluble layer 16 between the ink layer 12 and the substrate 11. Therefore, when the PET bottle container 1 is treated with an alkaline solution, the alkali-soluble layer 16 dissolves, causing the wrap-around label 10B to separate from the PET bottle container 1.

[0045] As a result, as shown in FIG. 11 , after the wrap-around label 10B is peeled off from the PET bottle container 1, the first adhesive layer 13 and the ink layer 12 remain on the PET bottle container 1. That is, the ink layer 12 remains attached to the first adhesive layer 13. Therefore, when the PET bottle container 1 is crushed into container fragments for recycling, the container fragments to which the first adhesive layer 13 is attached can be identified. This makes it possible to selectively remove container fragments to which the first adhesive layer 13 is attached, thereby improving the quality of recycled products. Note that the ink layer 12 does not maintain its outer diameter by itself, but appears to exist as a layer due to the presence of an object to which it is attached, such as the substrate 11. Therefore, after the wrap-around label 10B is peeled off from the PET bottle container 1, as shown in FIG. 11 , the ink layer 12 remains on the first adhesive layer 13, but the layer shape cannot be maintained in other areas.

[0046] The alkaline solution used to peel the wrap-around label 10B from the PET bottle container 1 is not particularly limited as long as it can dissolve the alkali-soluble layer 16, and may be an alkaline aqueous solution containing an alkaline substance. Examples of alkaline solutions that can be used include aqueous sodium hydroxide and aqueous potassium hydroxide. The concentration of the alkaline substance in the alkaline solution can be appropriately selected within a range that does not impair operability or workability, and is preferably, for example, about 0.5 to 6% by weight. The treatment with the alkaline solution can be carried out, for example, by immersing the PET bottle container 1 in the alkaline solution for about 1 to 20 minutes. The preferred temperature of the alkaline solution is 50 to 95°C.

[0047] In the recycling method using the PET bottle container 1 in this embodiment, in the separation step S1, instead of the method of physically separating the wrap-around label 10 from the PET bottle container 1 as described in embodiment 1, the wrap-around label 10B can be separated from the PET bottle container 1 by treating it with an alkaline solution.

[0048] In one embodiment of the present invention, in addition to the above configuration, the adhesion strength between the ink layer 12 and the first adhesive layer 13 may be greater than the adhesion strength between the ink layer 12 and the alkali-soluble layer 16. According to the above configuration, the first adhesive layer 13 and the ink layer 12 can be left on the PET bottle container 1 in both cases where the wrap-around label 10A is physically peeled off from the PET bottle container 1 and where a large amount of industrially collected discarded PET bottle containers 1 is chemically treated using an alkaline solution.

[0049] In one embodiment of the present invention, another layer may be present between the ink layer 12 and the alkali-soluble layer 16, or another layer may be present between the substrate 11 and the alkali-soluble layer 16.

[0050] Furthermore, the method of using an alkali-soluble layer described in this embodiment can also be applied to the configuration described in embodiment 2 in which both ends of the wrap-around label 10A are adhered to the container body 3 by adhesive layers.

[0051] [Embodiment 4] Another embodiment of the present invention will be described below. Fig. 12 is a cross-sectional view showing the configuration of a wrap-around label 10C before being wrapped around a PET bottle container 1 in this embodiment. Fig. 13 is an enlarged cross-sectional view of the PET bottle container 1, around the area where the wrap-around label 10C is adhered to the container body 3.

[0052] 12 and 13, the wrap-around label 10C has a rupture layer 17 in addition to the configuration of the wrap-around label 10 in embodiment 1. As shown in Fig. 12 and 13, the rupture layer 17 is a layer located between the ink layer 12 and the substrate 11. The rupture layer 17 is configured to rupture with a force smaller than the force required to peel the ink layer 12 and the first adhesive layer 13 apart.

[0053] The "force at which the rupture layer 17 breaks" and the "force at which the ink layer 12 and the first adhesive layer 13 peel off" can be compared, for example, as follows. That is, after the rupture layer 17 and the ink layer 12 are formed in this order on the substrate 11, the ink layer 12 and the PET sheet are bonded together with the first adhesive layer 13. Then, a force is applied to the bonded portion in a 180-degree direction, and a comparison can be made based on whether the rupture layer 17 breaks or whether the ink layer 12 and the first adhesive layer 13 peel off from each other.

[0054] As shown in Figure 13, in the PET bottle container 1 of this embodiment, similar to the PET bottle container 1 of embodiment 1, one end 10Ca of the wrap-around label 10C is adhered to the container body 3 by a first adhesive layer 13, and the other end 10Cb of the wrap-around label 10C is adhered to the base material 11 by a second adhesive layer 14.

[0055] 14 is an enlarged cross-sectional view showing the area of ​​the PET bottle container 1 where the first adhesive layer 13 was adhered after the wrap-around label 10C has been physically peeled off from the PET bottle container 1. The PET bottle container 1 in this embodiment has a rupture layer 17 between the ink layer 12 and the substrate 11, which is configured to rupture with a force smaller than the force required to peel the ink layer 12 and the first adhesive layer 13. Therefore, when the wrap-around label 10C is physically peeled off from the PET bottle container 1, the ink layer 12 does not peel off from the first adhesive layer 13, and the rupture layer 17 ruptures.

[0056] As a result, as shown in Figure 14, after the wrap-around label 10C is peeled off from the PET bottle container 1, the first adhesive layer 13, the ink layer 12, and the rupture layer 17 remain on the PET bottle container 1, with the ink layer 12 remaining attached to the first adhesive layer 13. Therefore, when the PET bottle container 1 is crushed into container fragments for recycling, it is possible to identify the container fragments to which the first adhesive layer 13 is attached. This makes it possible to selectively remove container fragments to which the first adhesive layer 13 is attached, thereby improving the quality of the recycled products manufactured.

[0057] [Embodiment 5] Another embodiment of the present invention will be described below. Fig. 15 is a cross-sectional view showing the configuration of a wrap-around label 10D before being wrapped around a PET bottle container 1 in this embodiment. Fig. 16 is an enlarged cross-sectional view of the PET bottle container 1 around the area where the wrap-around label 10D is adhered to the container body 3.

[0058] 15 and 16, the wrap-around label 10D has a rupture layer 18 in addition to the configuration of the wrap-around label 10A in embodiment 2. As shown in Figures 15 and 16, the rupture layer 18 is a layer located between the ink layer 12 and the substrate 11. The rupture layer 18 is configured to rupture with a force that is smaller than the force required to peel the substrate 11 and the first adhesive layer 13, and smaller than the force required to peel the substrate 11 and the third adhesive layer 15.

[0059] As shown in Figure 16, in the PET bottle container 1 of this embodiment, similar to the PET bottle container 1 of embodiment 2, one end 10Da of the wrap-around label 10D is adhered to the container body 3 by a first adhesive layer 13, and the other end 10Db of the wrap-around label 10D is adhered to the container body 3 by a third adhesive layer 15.

[0060] 17 is an enlarged cross-sectional view showing the area of ​​the PET bottle container 1 where the first adhesive layer 13 and the third adhesive layer 15 were adhered after the wrap-around label 10D has been physically peeled off from the PET bottle container 1. The PET bottle container 1 in this embodiment has a rupture layer 18 between the ink layer 12 and the substrate 11. The rupture layer 18 is configured to rupture with a force smaller than that required to peel the ink layer 12 and the first adhesive layer 13 and smaller than that required to peel the substrate 11 and the third adhesive layer 15. Therefore, when the wrap-around label 10D is physically peeled off from the PET bottle container 1, the ink layer 12 does not peel off from the first adhesive layer 13 and the third adhesive layer 15, and the rupture layer 18 ruptures. An example of the rupture layer 18 is a layer similar to the rupture layer 17 described above.

[0061] As a result, as shown in Figure 17, after the wrap-around label 10D is peeled off from the PET bottle container 1, the first adhesive layer 13, the third adhesive layer 15, the ink layer 12, and the rupture layer 18 remain on the PET bottle container 1, and the ink layer 12 remains attached to the first adhesive layer 13 and the third adhesive layer 15. Therefore, when the PET bottle container 1 is crushed into container fragments for recycling, it is possible to identify those container fragments to which the first adhesive layer 13 or the third adhesive layer 15 is attached. This makes it possible to selectively remove container fragments to which the first adhesive layer 13 or the third adhesive layer 15 is attached, thereby improving the quality of the recycled products manufactured.

[0062] [Embodiment 6] Another embodiment of the present invention will be described below. Fig. 18 is a cross-sectional view showing the configuration of a wrap-around label 10E in this embodiment before it is wrapped around a PET bottle container 1. Fig. 19 is an enlarged cross-sectional view of the PET bottle container 1 around the area where the wrap-around label 10E is adhered to the container body 3.

[0063] 18 and 19, the wrap-around label 10E has an ink layer 12A instead of the ink layer 12 of the wrap-around label 10 in embodiment 1. The ink layer 12A is configured to break with a force smaller than the force required to peel the ink layer 12A and the first adhesive layer 13 apart.

[0064] As shown in Figure 19, in the PET bottle container 1 of this embodiment, one end 10Ea of the wrap-around label 10E is adhered to the container body 3 by a first adhesive layer 13, and the other end 10Eb of the wrap-around label 10E is adhered to the base material 11 by a second adhesive layer 14.

[0065] 20 is an enlarged cross-sectional view showing the area of ​​the PET bottle container 1 where the first adhesive layer 13 was adhered after the wrap-around label 10E has been physically peeled off from the PET bottle container 1. The PET bottle container 1 in this embodiment has an ink layer 12A that is configured to break with a force smaller than the force required to peel the ink layer 12A from the first adhesive layer 13. Therefore, when the wrap-around label 10E is physically peeled off from the PET bottle container 1, the ink layer 12A does not peel off from the first adhesive layer 13, but breaks.

[0066] As a result, as shown in Figure 20, after the wrap-around label 10E is peeled off from the PET bottle container 1, the first adhesive layer 13 and part of the ink layer 12A remain on the PET bottle container 1, and part of the ink layer 12A remains attached to the first adhesive layer 13. Therefore, when the PET bottle container 1 is crushed into container fragments for recycling, it is possible to recognize the container fragments to which the first adhesive layer 13 is attached. This makes it possible to selectively remove container fragments to which the first adhesive layer 13 is attached, thereby improving the quality of the recycled products manufactured.

[0067] [Embodiment 7] Another embodiment of the present invention will be described below. Fig. 21 is a cross-sectional view showing the configuration of a wrap-around label 10F before being wrapped around a PET bottle container 1 in this embodiment. Fig. 22 is an enlarged cross-sectional view of the PET bottle container 1 around the area where the wrap-around label 10F is adhered to the container body 3.

[0068] 21 and 22, the wrap-around label 10F has an ink layer 12B instead of the ink layer 12 of the wrap-around label 10A in embodiment 2. The ink layer 12B is configured to break with a force that is smaller than the force required to peel the ink layer 12B from the first adhesive layer 13 and smaller than the force required to peel the ink layer 12B from the third adhesive layer 15.

[0069] As shown in Figure 22, in the PET bottle container 1 of this embodiment, one end 10Fa of the wrap-around label 10F is adhered to the container body 3 by a first adhesive layer 13, and the other end 10Fb of the wrap-around label 10F is adhered to the container body 3 by a third adhesive layer 15.

[0070] 23 is an enlarged cross-sectional view showing the area of ​​the PET bottle container 1 where the first adhesive layer 13 and the third adhesive layer 15 were adhered after the wrap-around label 10F has been physically peeled off from the PET bottle container 1. The PET bottle container 1 in this embodiment has an ink layer 12B that is configured to break with a force that is smaller than the force required to peel the ink layer 12B from the first adhesive layer 13 and smaller than the force required to peel the ink layer 12B from the third adhesive layer 15. Therefore, when the wrap-around label 10F is physically peeled off from the PET bottle container 1, the ink layer 12B breaks without peeling off the first adhesive layer 13 and the third adhesive layer 15.

[0071] As a result, as shown in Figure 23, after the wrap-around label 10F is peeled off from the PET bottle container 1, the first adhesive layer 13, the third adhesive layer 15, and a portion of the ink layer 12B remain on the PET bottle container 1, and a portion of the ink layer 12B remains attached to the first adhesive layer 13 and the third adhesive layer 15. Therefore, when the PET bottle container 1 is crushed into container fragments for recycling, it is possible to identify those container fragments to which the first adhesive layer 13 or the third adhesive layer 15 is attached. This makes it possible to selectively remove container fragments to which the first adhesive layer 13 or the third adhesive layer 15 is attached, thereby improving the quality of the recycled products manufactured.

[0072] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Explanation of symbols]

[0073] 1 PET bottle container 10, 10A, 10B, 10C, 10D, 10E, 10F Wrap-around labels 11 Base material 12, 12A, 12B ink layers 13 First adhesive layer 14 Second adhesive layer 15 Third adhesive layer 16 Alkali-soluble layer 17, 18 Fracture layer

Claims

1. a separation step of peeling the wrap-around label from the container around which the wrap-around label is wrapped, to separate the container from the wrap-around label; a crushing step of crushing the container from which the wrap-around label has been separated into container pieces; a removing step of removing container fragments having an ink layer attached thereto from the plurality of container fragments produced by the crushing step, The container on which the wrap-around label is wrapped is the wrap-around label includes the container, a substrate and the ink layer, a first adhesive layer that adheres one end of the wrap-around label to the container, and a second adhesive layer that adheres the other end of the wrap-around label to the substrate, the first adhesive layer and the second adhesive layer are located on the side of the ink layer opposite to the substrate side, A sorting method in which, after the wrap-around label is peeled off from the container, at least a portion of the ink layer remains attached to the first adhesive layer remaining on the container.

2. The sorting method according to claim 1 , wherein the removing step includes a step of identifying the color of the ink layer.

3. The sorting method according to claim 2 , wherein the color of the ink layer remaining attached to the first adhesive layer is different from the color of the container.

4. a separation step of peeling the wrap-around label from the container around which the wrap-around label is wrapped, to separate the container from the wrap-around label; a crushing step of crushing the container from which the wrap-around label has been separated into container pieces; a removing step of removing container fragments having an ink layer attached thereto from the plurality of container fragments produced by the crushing step; and a step of manufacturing a recycled product by using the container pieces after removing the container pieces to which the ink layer is attached as at least a part of the material, The container on which the wrap-around label is wrapped is the wrap-around label includes the container, a substrate and the ink layer, a first adhesive layer that adheres one end of the wrap-around label to the container, and a second adhesive layer that adheres the other end of the wrap-around label to the substrate, the first adhesive layer and the second adhesive layer are located on the side of the ink layer opposite to the substrate side, A method for manufacturing recycled goods, wherein after the wrap-around label is peeled off from the container, at least a portion of the ink layer remains attached to the first adhesive layer remaining on the container.

5. a separation step of peeling the wrap-around label from the container around which the wrap-around label is wrapped, to separate the container from the wrap-around label; a crushing step of crushing the container from which the wrap-around label has been separated into container pieces; a removing step of removing container fragments having an ink layer attached thereto from the plurality of container fragments produced by the crushing step, The container on which the wrap-around label is wrapped is the wrap-around label includes the container; a substrate and the ink layer; a first adhesive layer that adheres one end of the wrap-around label to the container; and a third adhesive layer that adheres the other end of the wrap-around label to the container, the first adhesive layer is provided only on the one end portion, the third adhesive layer is provided only on the other end portion, the first adhesive layer and the third adhesive layer are located on the side of the ink layer opposite to the substrate side, A sorting method in which, after the wrap-around label is peeled off from the container, at least a portion of the ink layer remains attached to the first adhesive layer and the third adhesive layer remaining on the container.

6. a separation step of peeling the wrap-around label from the container around which the wrap-around label is wrapped, to separate the container from the wrap-around label; a crushing step of crushing the container from which the wrap-around label has been separated into container pieces; a removing step of removing container fragments having an ink layer attached thereto from the plurality of container fragments produced by the crushing step; and a step of manufacturing a recycled product by using the container pieces after removing the container pieces to which the ink layer is attached as at least a part of the material, The container on which the wrap-around label is wrapped is the wrap-around label includes the container; a substrate and the ink layer; a first adhesive layer that adheres one end of the wrap-around label to the container; and a third adhesive layer that adheres the other end of the wrap-around label to the container, the first adhesive layer is provided only on the one end portion, the third adhesive layer is provided only on the other end portion, the first adhesive layer and the third adhesive layer are located on the side of the ink layer opposite to the substrate side, A method for manufacturing recycled goods, wherein after the wrap-around label is peeled off from the container, at least a portion of the ink layer remains attached to the first adhesive layer and the third adhesive layer remaining on the container.

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