Laminated container and method for manufacturing the same

Abstract

To provide a laminated container 100 capable of making a label portion easy to dispose of as paper waste.SOLUTION: A laminated container 100 includes: a body part 20 that accommodates contents; a mouth part 10 connected to an upper end portion of the body part 20; a container part (bottle layer 22) having a bottom part 40 that closes a lower end portion of the body part 20; and a label part 28 covering at least a part of the body part 20 from the outside. The label part 28 has a release layer 24 laminated in a peelable manner to the outermost surface of the container part. The label part 28 contains 51 vol.% or more of a combustible waste component. The release layer 24 has a thickness of 200 μm or more and 300 μm or less.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a laminated container and a method for manufacturing the laminated container. [Background technology]

[0002] Currently, there is a demand for recycling resin containers in response to social demands such as reducing the burden on the environment. For example, Patent Document 1 proposes a container that is easy to recycle by wrapping a shrink label that displays the product name and a description of the contents around the body and cap of the container, and by removing the shrink label from the container body when recycling. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-176760 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the case of the shrink-labeled container described in Patent Document 1, the shrink label removed from the container body is usually plastic waste and may not be able to be disposed of as combustible waste like paper, so there was room for improvement in this regard.

[0005] The present disclosure aims to solve these problems, and its purpose is to propose a laminated container and a method for manufacturing a laminated container that makes it easier to dispose of the label portion as paper waste. [Means for solving the problem]

[0006] The laminated container of the present disclosure comprises: a container portion having a body portion for accommodating contents, a mouth portion connected to an upper end portion of the body portion, and a bottom portion closing a lower end portion of the body portion; a label portion that covers at least a portion of the body portion from the outside; Equipped with The label portion has a release layer that is releasably laminated to the outermost surface of the container portion, and the label portion contains 51% by weight or more of combustible waste components, and the combustible waste components are at least one of paper, calcium carbonate, and starch. Made up of , The thickness of the release layer is 200 μm or more and 300 μm or less. the law of nature, the label portion has a label layer laminated on an outer surface of the release layer, The release layer contains 25% by weight or more and 45% by weight or less of combustible waste components, The label layer contains 70% by weight or more and 100% by weight or less of combustible waste components and covers 40% or more of the surface of the container portion. It is characterized by:

[0009] In addition, in the laminated container of the present disclosure having the above configuration, the thickness of the label layer is preferably 50 μm or more and 300 μm or less.

[0010] Further, the method for manufacturing a laminated container according to the present disclosure includes: a container portion having a body portion for accommodating contents, a mouth portion connected to an upper end portion of the body portion, and a bottom portion closing a lower end portion of the body portion; a label portion that covers at least a portion of the body portion from the outside; A method for manufacturing a laminated container comprising: placing a label layer in a blow mold; a step of blow-molding the container portion and a release layer to be laminated on the outside of the container portion in the blow molding die, and laminating the label layer on the outside of the release layer as an in-mold label; Including, The label portion contains 51% by weight or more of combustible waste components, and the combustible waste components are at least one of paper, calcium carbonate, and starch. Made up of , The thickness of the release layer is 200 μm or more and 300 μm or less. [Effects of the Invention]

[0011] According to the present disclosure, it is possible to propose a laminated container that makes it easy to dispose of the label portion as paper waste. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a front view of a stacked container according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a partial cross-sectional view of a right side view of a laminated container according to an embodiment of the present disclosure. [Figure 3] FIG. 3 is a detailed view of part A in FIG. 2. [Figure 4] 1 is a flowchart showing the steps of a method for manufacturing a stacked container according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0013] The present disclosure will be described in more detail below with reference to the drawings.

[0014] FIG. 1 is a front view showing the configuration of a stacked container 100 according to one embodiment of the present disclosure. The stacked container 100 includes a substantially cylindrical body 20 that defines a storage space S for the contents, a mouth 10 that is connected to the upper end of the body 20 via a shoulder 30 and defines an opening 10a on the inside for supplying and discharging the contents, and a bottom 40 that closes the lower end of the body 20. As shown in FIGS. 1 and 2, the outer peripheral surface of the mouth 10 is provided with a male thread 10b that allows a cap, a pump, or the like to be attached by threaded engagement. A bottle layer 22 (container portion), shown in partial cross section in FIG. 2, defines the entire area of ​​the mouth 10, shoulder 30, body 20, and bottom 40 in FIGS. 1 and 2.

[0015] In this specification, claims, and drawings, the side where the mouth portion 10 is located is referred to as the upper side (upper side in FIG. 1), and the side where the bottom portion 40 is located is referred to as the lower side (lower side in FIG. 1). In addition, in describing the layer structure of the stacked container 100, the storage space S side is referred to as the inner side, and the label layer 26 side of the stacked container 100 is referred to as the outer side. Furthermore, the radially outer side refers to the direction away from the central axis O along a straight line that passes through the central axis O of the stacked container 100 in FIG. 1 and is perpendicular to the central axis O, and the radially inner side refers to the direction toward the central axis O along that straight line.

[0016] In addition, in this embodiment, the terms "innermost layer 24a" and "outermost layer 24c" are simply given as such because they refer to the innermost and outermost layers of the release layer 24 in the configuration illustrated in Fig. 3. The innermost layer 24a and the outermost layer 24c in this embodiment are not necessarily limited to configurations in which they are arranged as the innermost and outermost layers of the release layer 24.

[0017] As shown in Figures 2 and 3, the body portion 20 includes the above-mentioned bottle layer 22 (container portion) that forms the storage space S for the contents, and a label portion 28 that covers the bottle layer 22 from the radial outside and is peelably laminated to the bottle layer 22.

[0018] The bottle layer 22 forming the skeleton of the laminated container 100 can be formed of a resin primarily composed of a polyolefin resin such as polyethylene (PE) or polypropylene (PP), or a polyester resin such as polyethylene terephthalate (PET), polycyclohexylene dimethylene terephthalate (PCT), or polyethylene naphthalate (PEN). For example, when polyethylene is used for the bottle layer 22, low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), or high-density polyethylene resin (HDPE) can be used. In particular, when HDPE or PP is used, high rigidity can be imparted to the laminated container 100. Furthermore, when a single PET resin is used, it may be possible to collect and recycle it as a PET bottle. The bottle layer 22 may also be a resin layer formed of a resin other than a polyolefin resin or a polyester resin. Furthermore, the bottle layer 22 may be a resin layer formed of a virgin material such as a polyolefin resin or a polyester resin, or a resin layer formed by mixing a virgin material with a recycled material. Furthermore, a layer of virgin material and a layer containing recycled material may be laminated. The bottle layer 22 may also be made of recycled materials only.

[0019] The bottle layer 22 is preferably a single resin layer made of virgin material such as the polyolefin resin described above, a mixture of virgin material and recycled material, or recycled material alone. By making the bottle layer 22 a single resin layer, sorting of the laminated container 100 can be completed simply by peeling off the label portion 28. Furthermore, by recycling the bottle layer 22 from which the label portion 28 has been separated, it can be used as a single-material recycled material, thereby further improving recyclability. However, this is not limited to this embodiment, and the bottle layer 22 may be made by laminating multiple resin layers that can be sorted together. An example of a bottle containing multiple resin layers is when the bottle layer 22 is made of multiple resin layers including a mixture of virgin and recycled polypropylene material and virgin polypropylene material.

[0020] Furthermore, it is preferable that the bottle layer 22 does not contain a coloring material. By not containing a coloring material, the bottle layer 22 can be used as a recycled material that does not contain a coloring material. However, this is not limited to this embodiment, and the bottle layer 22 may contain a coloring material.

[0021] 2 and 3, the label part 28 includes a release layer 24, which is laminated in the order of an innermost layer 24a, an adhesive layer 24b, and an outermost layer 24c from the inside, and a label layer 26 laminated radially outward from the release layer 24. The release layer 24 is laminated on the outside of the bottle layer 22 so as to be releasable from the bottle layer 22.

[0022] 1 and 2, the label layer 26 provided on the outer side of the peeling layer 24 covers the outer side of the peeling layer 24 except for partial regions on the left and right sides of the body 20 (in FIGS. 1 and 2, the two-dot chain lines indicate the outer edge of the label layer 26). In addition, in partial regions on the left and right sides of the body 20 of the laminated container 100, the label part 28 has only the peeling layer 24 and does not have the label layer 26.

[0023] The configuration of the label portion 28 is not limited to the above-described embodiment, as long as the label layer 26 is laminated on the peel layer 24 in at least a portion of the body 20. The label layer 26 may also extend not only over the body 20 but also over at least a portion of the mouth 10, shoulder 30, and bottom 40. In this embodiment, the thickness of the bottle layer 22 is configured to be thicker than the label portion 28 in the entire area where the label layer 26 is formed. However, the present invention is not limited to this embodiment, and the thickness of the bottle layer 22 may be configured to be thinner than the label portion 28.

[0024] The innermost layer 24a of the release layer 24 forms the innermost surface of the label portion 28 and is made of a material that is incompatible with the outermost surface of the bottle layer 22 and can be peeled off from the bottle layer 22. When the bottle layer 22 is made of a resin primarily containing a polyolefin-based resin, the innermost layer 24a can be made of, for example, ethylene-vinyl alcohol copolymer resin (EVOH), polyamide (nylon), polyester-based resin (polyethylene terephthalate (PET), polycyclohexylene dimethylene terephthalate (PCT), polyethylene naphthalate (PEN), etc.), polycarbonate (PC), ionomer (product name: Himilan (registered trademark)), or cyclic olefin copolymer. When the bottle layer 22 is made of a material primarily containing a polyester-based resin, the innermost layer 24a can be made of, for example, EVOH, polyamide, polyolefin-based resin, PC, ionomer, or cyclic olefin copolymer. In this embodiment, EVOH is used for the innermost layer 24a.

[0025] In particular, by using EVOH, polyamide, or the like for the innermost layer 24a, the gas barrier properties of the laminated container 100 can be improved, thereby suppressing deterioration of the contents due to exposure to air. Also, a resin layer having light-blocking properties may be laminated in place of or together with the gas barrier resin layer. Furthermore, an additional resin layer may be provided radially inward of the innermost layer 24a.

[0026] In this embodiment, as shown in FIG. 3, the outermost layer 24c of the release layer 24 is laminated to the innermost layer 24a via the adhesive layer 24b.

[0027] The outermost layer 24c can be made of a resin primarily composed of a polyolefin resin such as polyethylene (PE) or polypropylene (PP), or a polyester resin such as polyethylene terephthalate (PET), polycyclohexylene dimethylene terephthalate (PCT), or polyethylene naphthalate (PEN). The proportion of combustible waste components in the release layer 24 is adjusted to 25% to 45% by weight by incorporating one or more of paper (cellulose particles), calcium carbonate, and starch into the primary material. The combustible waste components referred to here do not refer to petroleum-derived synthetic resins, but rather to components that can be disposed of as paper and burned. The combustible waste components are not necessarily limited to paper (cellulose particles), calcium carbonate, and starch.

[0028] The outermost layer 24c may be made up of two or more resin layers, as long as at least one of the plurality of resin layers contains the above-mentioned burnable waste component.

[0029] In this embodiment, the thickness of the release layer 24, which includes the innermost layer 24a, the adhesive layer 24b, and the outermost layer 24c, is set to 200 μm or more and 300 μm or less. By setting the thickness of the release layer 24 to 200 μm or more, it is possible to ensure the formability of the release layer 24 and the releasability of the release layer 24 from the bottle layer 22, even if the release layer 24 is mixed with combustible waste components in a range of 25% by weight to 45% by weight. Furthermore, by setting the thickness of the release layer 24 to 300 μm or less, it is possible to reduce the amount of resin material used in an environmentally friendly manner.

[0030] In this embodiment, a label layer 26 is laminated on the outer surface of the outermost layer 24c of the release layer 24. In this embodiment, the label layer 26 is a paper in-mold label that can be attached to the outer surface of the release layer 24 during in-mold molding. The label layer 26 contains 70% to 100% by weight of paper components, which are combustible waste. In this way, in this embodiment, the label layer 26 of the label portion 28 contains a large amount (70% by weight or more) of paper components, which are combustible waste, thereby increasing the proportion of combustible waste components in the label portion 28 to 51% by weight or more. Note that the label layer 26 may not be provided on the outer surface of the outermost layer 24c of the release layer 24, and the proportion of paper components, which are combustible waste, in the release layer 24 may be 51% by weight or more.

[0031] The label layer 26 of this embodiment is a label component formed as an in-mold label when the bottle layer 22 and the release layer 24 are extrusion blow molded, and contains 70% to 100% by weight of paper, which is combustible waste. In this embodiment, the label layer 26 is placed in advance in a blow molding die that extrusion blow molds the bottle layer 22 and the release layer 24, as described below, and is laminated to the outermost layer 24c of the release layer 24 by extrusion blow molding. Note that the attachment strength of the label layer 26 may be increased by providing an additional adhesive layer between the outermost layer 24c of the release layer 24 and the label layer 26, or by intertwining the label edge with the surface of the release layer 24, as described in Japanese Patent No. 6120755.

[0032] In this embodiment, the label layer 26 has a thickness of 250 μm. The thickness of the label layer 26 is preferably 50 μm or more and 300 μm or less, and more preferably 100 μm or more and 250 μm or less.

[0033] By making the thickness of the label layer 26 50 μm or more, the proportion of combustible waste components in the entire label portion 28 can be increased, and by making the thickness of the label layer 26 100 μm or more, the proportion of combustible waste components can be increased even more effectively.

[0034] Furthermore, by setting the thickness of the label layer 26 to 300 μm or less, the bending rigidity can be kept low, so that even if the portion where the label layer 26 is provided has a curved shape, the restoring force of the label layer 26 trying to return to its original shape from the curved shape does not affect the formability of the body portion 20. By setting the thickness of the label layer 26 to 250 μm or less, the effect of the restoring force of the label layer 26 on the formability of the body portion 20 can be more effectively prevented.

[0035] In this embodiment, the label layer 26 preferably has an area of ​​40% or more of the surface area of ​​the laminated container 100. With this configuration, it is possible to ensure that the burnable waste component in the label portion 28 is 51% by weight or more when the burnable waste component in the peel layer 24 is 35% by weight. In addition, it is preferable that the label layer 26 has an area of ​​70% or less of the surface area of ​​the laminated container 100. With this configuration, the label layer 26 can be made large enough to be inserted into a blow molding mold, making it easier to form an in-mold label.

[0036] In this embodiment, by increasing the proportion of burnable waste components in the label portion 28 to 51% by weight or more, the label portion 28 peeled off from the bottle layer 22 can be disposed of as paper. With this configuration, the bottle layer 22 after the label portion 28 has been peeled off can potentially be collected and recycled as, for example, a PET bottle, while the label portion 28 can be disposed of as paper, so that the laminated container 100 after use can be disposed of without generating non-burnable waste.

[0037] As a method for increasing the percentage of combustible waste components in the label portion 28 to 51% by weight or more, it is possible to increase the percentage of combustible waste components in the release layer 24 to 51% by weight or more without using the label layer 26. However, if the percentage of combustible waste components in the release layer 24 exceeds 45% by weight, the formability of the release layer 24 and its releasability from the bottle layer 22 tend to decrease, as described below. In this embodiment, the percentage of combustible waste components in the release layer 24 is kept to 45% by weight or less, while a label layer 26 containing a paper component of 70% by weight to 100% by weight or less is laminated radially outward of the release layer 24, thereby increasing the percentage of combustible waste components in the entire label portion 28 that peels off from the bottle layer 22 to 51% or more. This configuration ensures the formability and releasability of the release layer 24, and allows the label portion 28 peeled off from the bottle layer 22 to be discarded as paper.

[0038] In the present embodiment, the release layer 24 is configured such that the outermost layer 24c is laminated on the outside of the innermost layer 24a via the adhesive layer 24b, but this is not limiting. An adhesive resin may be mixed into at least one of the innermost layer 24a or the outermost layer 24c, and the outermost layer 24c may be adhered and laminated to the innermost layer 24a without using the adhesive layer 24b.

[0039] The peeling layer 24 may be composed of only the innermost layer 24a or the outermost layer 24c. In this case, the peeling layer 24 may be configured so that the combustible waste component is kneaded into the innermost layer 24a or the outermost layer 24c.

[0040] In this embodiment, the outer surface of the label layer 26 may be decorated by means of printing, transferring, vapor deposition, painting, or adding a coloring material.

[0041] In this embodiment, for example, when inkjet printing is used, which allows for easy printing on thin-walled containers, the labels 28 can be separated by peeling them off from the bottle layer 22. This allows for both a reduction in environmental impact through thinning and easy container separation. Also, when silk screen printing is used for decoration, the print can sometimes be removed by washing, but in this embodiment, washing is not necessary.

[0042] In this embodiment, the entire area of ​​the release layer 24 is configured to be peelable from the bottle layer 22. However, the entire area of ​​the release layer 24 does not necessarily have to be peelable from the bottle layer 22. For example, the release layer 24 may be provided over the entire area from the mouth 10 to the bottom 40 of the laminated container 100, and the release layer 24 and the bottle layer 22 may be partially fixed together by complex irregularities such as the male thread portion 10b of the mouth 10. In this case, it is preferable that the label layer 26 is laminated on an area of ​​the release layer 24 that is peelable from the bottle layer 22. Alternatively, the release layer 24 and the bottle layer 22 may be peelably bonded together with an adhesive or the like.

[0043] As described above, even if the bottle layer 22 and the release layer 24 are partially bonded together and difficult to separate, the release layer 24 may be configured to be easily separated from the bottle layer 22 by forming, for example, a weakened portion or a cut in the release layer 24. With such a configuration, the peelable release layer 24 and the label layer 26 laminated thereon can be easily separated from the bottle layer 22 and separated.

[0044] Furthermore, through holes may be formed in the outer surfaces of the mouth 10, bottom 40, etc. of the laminated container 100, and air may be blown through the through holes so that the release layer 24 can be easily peeled off from the bottle layer 22.

[0045] 1 to 3 can be manufactured by, for example, extrusion blow molding. When manufacturing the laminated container 100, first, the label layer 26 is placed near the wall surface inside the blow molding die (step S101 in FIG. 4). The label layer 26 placed inside the blow molding die is fixed inside the blow molding die by means of vacuum suction or the like.

[0046] Next, a laminated parison in which the resin layer constituting the bottle layer 22 (container portion) and the resin layer constituting the release layer 24 are laminated is supplied into a blow molding mold, and the bottle layer 22 and the release layer 24 are extrusion blow molded, and the label layer 26 is laminated on the outside of the release layer 24 as an in-mold label (step S103 in FIG. 4). As described above, the label layer 26 may have an additional adhesive layer between the outermost layer 24c of the release layer 24 and the label layer 26, or an adhesive may be applied to the inner side of the label layer 26, or the label edge and the surface of the release layer 24 may be entangled to increase the attachment strength.

[0047] When the extrusion blow molding is completed, the vacuum suction of the label layer 26 is stopped, the mold is opened, and the laminated container 100 is removed, thereby completing the manufacturing process.

[0048] This laminated structure of the bottle layer 22 and the peel layer 24 may be formed by extrusion blow molding, or by stretch blow molding a laminated preform in which the bottle layer 22 and the peel layer 24 are laminated, and in-mold molding the label layer 26.

[0049] As described above, the laminated container 100 according to this embodiment comprises a container portion (bottle layer 22) having a body portion 20 for accommodating contents, a mouth portion 10 connected to the upper end of the body portion 20, and a bottom portion 40 closing the lower end of the body portion 20, and a label portion 28 covering at least a portion of the body portion 20 from the outside, the label portion 28 having a release layer 24 removably laminated to the outermost surface of the container portion, the label portion 28 containing 51% by weight or more of combustible waste components, and the thickness of the release layer 24 being 200 μm or more and 300 μm or less. By adopting such a configuration, separation is completed by peeling the label portion 28 from the container portion (bottle layer 22) after use of the contents, making it possible to recycle the container portion and to easily dispose of the label portion 28 as paper waste.

[0050] In this embodiment, the label portion 28 is configured to have a label layer 26 laminated on the outer surface of the release layer 24. By adopting such a configuration, the label layer 26 is laminated on the release layer 24 as an in-mold label, and the laminated container 100 can be formed only through the bottle molding process, thereby reducing the manufacturing cost of the laminated container 100 having the label layer 26 containing a paper component. In addition, the formability of the release layer 24 and its releasability from the bottle layer 22 can be ensured.

[0051] In this embodiment, the release layer 24 contains 25% to 45% by weight of combustible waste components, and the label layer 26 contains 70% to 100% by weight of combustible waste components and is configured to cover 40% or more of the surface of the container. By adopting this configuration, the proportion of combustible waste components in the entire label portion 28 is set to 51% or more without reducing the formability of the release layer 24 or the releasability from the container, and the label portion 28 can be disposed of as paper.

[0052] In this embodiment, the thickness of the label layer 26 is set to be 50 μm or more and 300 μm or less. By adopting such a configuration, it is possible to effectively increase the proportion of burnable waste components in the entire label portion 28, and also to effectively prevent the restoring force of the label layer 26 from affecting the formability of the body portion 20.

[0053] This embodiment is a manufacturing method for a laminated container 100 including a container portion (bottle layer 22) having a body 20 for accommodating contents, a mouth 10 connected to the upper end of the body 20, and a bottom 40 closing the lower end of the body 20, and a label portion 28 covering at least a portion of the body 20 from the outside. The method includes the steps of placing a label layer 26 in a blow molding mold, blow molding the container portion and a release layer 24 laminated to the outside of the container portion in the blow molding mold, and laminating the label layer 26 on the outside of the release layer 24 as an in-mold label, wherein the label portion 28 contains 51% by weight or more of combustible waste components, and the release layer 24 has a thickness of 200 μm to 300 μm. By adopting this configuration, separation is completed by peeling the label portion 28 from the container portion (bottle layer 22) after use of the contents, making it easy to recycle the container portion and dispose of the label portion 28 as paper waste. Furthermore, by laminating the label layer 26 as an in-mold label on the release layer 24, the laminated container 100 can be formed only through the bottle molding process, thereby reducing the manufacturing cost of the laminated container 100 having the label layer 26 containing a paper component. Furthermore, the formability of the release layer 24 and its releasability from the bottle layer 22 can be ensured.

[0054] Although the present disclosure has been described based on various drawings and examples, it should be noted that those skilled in the art can easily make various modifications and alterations based on the present disclosure. Therefore, it should be noted that these modifications and alterations are included in the scope of the present invention. For example, the functions included in each component can be rearranged so as not to cause logical inconsistencies, and multiple components can be combined into one or divided. It should be understood that these modifications and alterations are also included in the scope of the present invention.

[0055] For example, in this embodiment, the outer peripheral surface of the mouth portion 10 is provided with a male thread portion 10b so that an attachment cap, pump, etc. can be attached by threaded engagement, but this is not limited to this embodiment. The mouth portion 10 may be provided with an annular protrusion for attaching an attachment cap, pump, etc. by stopper engagement instead of or in addition to the male thread portion 10b. Also, the mouth portion 10 may be configured without an engagement portion.

[0056] In addition, in the present embodiment, the laminated container 100 is formed by blow molding a laminated parison formed by extrusion molding or by stretch blow molding a laminated preform, but the present invention is not limited to these forms. The laminated container 100 may be formed, for example, by two-color molding, or by setting multiple preforms in a mold and performing stretch blow molding.

[0057] Furthermore, the present disclosure can be widely applied not only to the laminated container 100 having a body 20 with a substantially cylindrical shape as shown in FIG. 1, but also to rectangular containers, pouch containers, cup containers, and the like. [Example]

[0058] In order to confirm the formability of the laminated container 100 of the present disclosure and the peelability of the release layer 24 from the bottle layer 22, prototypes were produced and evaluated in Examples 1 to 7 (see Table 1) in which the proportion of combustible waste components (paper) in the release layer 24 was varied. Table 2 also shows the conditions common to Examples 1 to 7.

[0059] [Table 1]

[0060] [Table 2]

[0061] According to the evaluation results shown in Table 1, by keeping the proportion of the paper component in the release layer 24 at 45% by weight or less, it is possible to maintain good formability and releasability of the release layer 24. More specifically, when the proportion of the paper component in the release layer 24 was increased to 50% by weight (Example 7), the release layer 24 did not stretch uniformly during blow molding (a formability problem), and the release layer 24 sometimes broke when being peeled from the bottle layer 22 (a releasability problem); however, by keeping the proportion of the paper component in the release layer 24 at 45% by weight or less, it was possible to prevent the above problems from occurring.

[0062] Furthermore, by setting the paper content of the release layer 24 to 25% by weight or more (i.e., by setting the area of ​​the label layer 26 to 70% or less of the surface area of ​​the laminated container 100), the ratio of the label layer 26 area to the surface area of ​​the laminated container 100 can be set to 69.6% or less, which is an easily achievable ratio, in order to achieve a paper content of 51% or more by weight in the label portion 28. Furthermore, as shown in Table 1, by setting the paper content of the release layer 24 to 25% by weight or more, the label layer 26 can be made to a size that can be inserted into a blow molding mold. When the paper content of the release layer 24 was set to 20% by weight (Example 1), the surface area of ​​the label layer 26 was too large to insert into the blow molding mold.

[0063] Next, the thickness of the label layer 26 was optimized using the conditions in Table 2. Table 3 shows the evaluation results.

[0064] [Table 3]

[0065] According to Table 3, when the thickness of the label layer 26 was 300 μm or less (Examples 8 and 9), the label layer 26 could be inserted into a blow molding die and laminated as an in-mold label. The note in Example 9, "Only insertable when the body portion has a shape close to a flat surface," means that when the body portion 20 has a curved surface with a small radius of curvature, the restoring force of the label layer 26 could not maintain the state following the curved surface. On the other hand, when the thickness of the label layer 26 was 480 μm (Example 10), the body portion 20 ruptured at the edge of the label layer 26, and the laminated container 100 could not be formed. This is thought to be because, in Example 10, the bending rigidity of the label layer 26 was high, and concentrated stress was generated in the body portion 20 due to the restoring force trying to return to its original shape. [Industrial Applicability]

[0066] According to the present disclosure, it is possible to propose a laminated container 100 that allows label portions 28 to be easily disposed of as paper waste. [Explanation of symbols]

[0067] 10 Mouth 10a opening 10b Male thread 20 Torso 22 Bottle layer (container part) 24 Peeling layer 24a innermost layer 24b Adhesive layer 24c outermost layer 26 Label Layer 28 Label section 30 Shoulder 40 bottom 100 laminated container O center axis S Storage space

Claims

1. a container portion having a body portion for accommodating contents, a mouth portion connected to an upper end portion of the body portion, and a bottom portion closing a lower end portion of the body portion; a label portion that covers at least a portion of the body portion from the outside; Equipped with The label portion has a release layer that is releasably laminated to the outermost surface of the container portion, the label portion contains 51% by weight or more of combustible waste components, and the combustible waste components are at least one of paper, calcium carbonate, and starch, The thickness of the release layer is 200 μm or more and 300 μm or less, the label portion has a label layer laminated on an outer surface of the release layer, The release layer contains 25% by weight or more and 45% by weight or less of combustible waste components, A laminated container characterized in that the label layer contains 70% by weight or more and 100% by weight or less of combustible waste components and covers 40% or more of the surface of the container portion.

2. 2. The laminated container according to claim 1, wherein the label layer has a thickness of 50 μm or more and 300 μm or less.

3. a container portion having a body portion for accommodating contents, a mouth portion connected to an upper end portion of the body portion, and a bottom portion closing a lower end portion of the body portion; a label portion that covers at least a portion of the body portion from the outside; A method for manufacturing a laminated container comprising: placing a label layer in a blow mold; a step of blow-molding the container portion and a release layer to be laminated on the outside of the container portion in the blow molding mold, and laminating the label layer on the outside of the release layer as an in-mold label; Including, The label portion contains 51% by weight or more of combustible waste components, and the combustible waste components are made of at least one of paper, calcium carbonate, and starch, A method for manufacturing a laminated container, wherein the thickness of the release layer is 200 μm or more and 300 μm or less.

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