JP2023151492A - Laminated container and manufacturing method for the same - Google Patents

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

The present disclosure relates to a laminated container and a method of manufacturing the laminated container.

Currently, there is a demand for recycling of resin containers due to social demands such as reducing the burden on the environment. For example, Patent Document 1 proposes a container that is made easier to recycle by wrapping a shrink label displaying the product name and contents around the body and cap of the container, and removing the shrink label from the container body when recycling. has been done.

Japanese Patent Application Publication No. 2012-176760

However, in the container with a shrink label described in Patent Document 1, the shrink label removed from the container body is usually plastic waste and may not be disposed of as combustible waste like paper, so there is room for improvement in this respect. Ta.

The present disclosure aims to solve such problems, and the purpose is to propose a laminated container and a method for manufacturing the laminated container that can make it easier to dispose of the label part as paper waste. That's true.

The laminated container of 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;
The label part has a release layer that is removably laminated on the outermost surface of the container part, and the label part contains 51% by weight or more of a combustible waste component,
The peeling layer has a thickness of 200 μm or more and 300 μm or less.

Further, in the laminated container of the present disclosure, in the above configuration, it is preferable that the label portion has a label layer laminated on the outer surface of the release layer.

Further, in the laminated container of the present disclosure, in the above configuration, the release layer contains 25% by weight or more and 45% by weight or less of a combustible waste component, and the label layer contains 70% by weight or more and 100% by weight or less of a combustible waste component. It is also preferable that at least 40% of the surface of the container portion be covered.

Further, in the laminated container of the present disclosure, in the above configuration, the thickness of the label layer is preferably 50 μm or more and 300 μm or less.

Further, the method for manufacturing a laminated container of 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 method for manufacturing a laminated container, comprising: a label portion that covers at least a portion of the body portion from the outside;
placing a label layer within the blow mold;
blow-molding the container part and a release layer laminated on the outside of the container part in the blow molding mold, and laminating the label layer as an in-mold label on the outside of the release layer. ,
The label portion contains 51% by weight or more of combustible waste components,
The peeling layer has a thickness of 200 μm or more and 300 μm or less.

According to the present disclosure, it is possible to propose a stacked container whose label portion can be easily disposed of as paper waste.

FIG. 1 is a front view of a stacked container according to an embodiment of the present disclosure. FIG. 2 is a partial cross-sectional view of the right side of a stacked container according to an embodiment of the present disclosure. 3 is a detailed view of part A in FIG. 2. FIG. 1 is a flowchart illustrating a procedure for manufacturing a laminated container according to an embodiment of the present disclosure.

Hereinafter, the present disclosure will be described in more detail with reference to the drawings.

FIG. 1 is a front view showing the configuration of a stacked container 100 that is an embodiment of the present disclosure. The stacked container 100 includes a generally cylindrical body 20 that forms a storage space S for contents, and an opening 10a that is connected to the upper end of the body 20 via a shoulder 30 and that supplies and discharges the contents. The body 20 has a mouth portion 10 that closes the lower end portion of the body portion 20, and a bottom portion 40 that closes the lower end portion of the body portion 20. As shown in FIGS. 1 and 2, the outer peripheral surface of the mouth portion 10 is provided with a male threaded portion 10b to which a cap, a pump, etc. can be attached by threaded engagement. The bottle layer 22 (container portion) shown partially in cross section in FIG. 2 forms the entire region of the mouth portion 10, shoulder portion 30, body portion 20, and bottom portion 40 in FIGS. 1 and 2.

Note that in this specification, claims, and drawings, the side where the mouth portion 10 is located is referred to as the upper side (the upper side in FIG. 1), and the side where the bottom portion 40 is located is referred to as the lower side (the lower side in FIG. 1). In addition, in the description of the layered structure of the stacked container 100, the side of the storage space S is referred to as the inside, and the side of the label layer 26 of the stacked container 100 is referred to as the outside. Further, the radially outer side is a direction away from the central axis O along a straight line passing through the central axis O of the stacked container 100 in FIG. It means the direction toward the central axis O.

In addition, in this embodiment, the words "innermost layer 24a" and "outermost layer 24c" are simply given such names because they are the innermost layer and the outermost layer 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 the configuration in which they are arranged as the innermost layer and the outermost layer of the release layer 24.

As shown in FIGS. 2 and 3, the body portion 20 covers the above-mentioned bottle layer 22 (container portion) that forms the storage space S for contents and the bottle layer 22 from the outside in the radial direction, and is also provided with respect to the bottle layer 22. The label part 28 is laminated in a peelable manner.

The bottle layer 22 forming the skeleton of the laminated container 100 is made of, for example, polyolefin resin such as polyethylene (PE) or polypropylene (PP), or polyethylene terephthalate (PET), polycyclohexylene dimethylene terephthalate (PCT), or polyethylene naphthalate. It can be formed from a resin whose main material is a polyester resin such as (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 some cases, high rigidity can be imparted to the laminated container 100. Furthermore, if a single PET resin is used, there is a possibility that it can be collected and recycled as a PET bottle. The bottle layer 22 may be a resin layer formed of a resin other than polyolefin resin and polyester resin. Further, the bottle layer 22 may be made of a virgin material such as a polyolefin resin or a polyester resin, or may be a resin layer made of a virgin material mixed with a recycled material. It is also possible to laminate a layer of virgin material and a layer containing recycled material. Moreover, the bottle layer 22 may be composed only of recycled materials.

The bottle layer 22 is preferably a single resin layer made of virgin material such as the above-mentioned polyolefin resin, a mixed material of virgin material and recycled material, or only recycled material. By making the bottle layer 22 a single resin layer, separation of the laminated containers 100 is completed only 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 recycled material, thereby further improving recyclability. However, the present invention is not limited to this embodiment, and the bottle layer 22 may be configured by laminating, for example, a plurality of resin layers that can be separated together. As an example of including a plurality of resin layers, for example, the bottle layer 22 may be configured with a plurality of resin layers including a mixed material of a virgin polypropylene material and a recycled material, and a plurality of resin layers including a virgin polypropylene material.

Moreover, it is preferable that the bottle layer 22 does not contain a coloring material. Since the bottle layer 22 does not contain a coloring material, it can be used as a recycled material that does not contain a coloring material. However, the present invention is not limited to this embodiment, and the bottle layer 22 may contain a coloring material.

In this embodiment, as shown in FIGS. 2 and 3, the label portion 28 includes a release layer 24 and a release layer 24 stacked in the order of innermost layer 24a, adhesive layer 24b, and outermost layer 24c from the inside. The label layer 26 is laminated on the outside in the radial direction. The peeling layer 24 is laminated on the outside of the bottle layer 22 so as to be peelable from the bottle layer 22.

In this embodiment, as shown in FIGS. 1 and 2, the label layer 26 provided on the outside of the release layer 24 is provided on the outer side of the release layer 24, except for a portion of the left side and right side of the body 20. It covers the outside (in FIGS. 1 and 2, the two-dot chain line indicates the outer edge of the label layer 26). Further, in a part of the left and right side surfaces of the body 20 of the laminated container 100, the label portion 28 has only the release layer 24 and does not have the label layer 26.

Note that the configuration of the label portion 28 is not limited to the above-described embodiment, and it is sufficient that the label layer 26 is laminated on the release layer 24 in at least a portion of the body portion 20. Further, the label layer 26 may extend not only to the trunk 20 but also to at least part of the mouth 10, the shoulder 30, and the bottom 40. In this embodiment, the thickness of the bottle layer 22 is configured to be thicker than the thickness of the label portion 28 in the entire region 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 thinner than the thickness of the label portion 28.

The innermost layer 24a of the peeling 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 from the bottle layer 22. When the bottle layer 22 is made of a resin whose main material is polyolefin resin, examples of the material for the innermost layer 24a include ethylene-vinyl alcohol copolymer resin (EVOH), polyamide (nylon), polyester resin (polyethylene terephthalate), etc. PET), polycyclohexylene dimethylene terephthalate (PCT), polyethylene naphthalate (PEN), etc.), polycarbonate (PC), ionomer (trade name: Himilan (registered trademark)), cyclic olefin copolymer, etc. can be used. Furthermore, when a material mainly composed of polyester resin is used for the bottle layer 22, EVOH, polyamide, polyolefin resin, PC, ionomer, or cyclic olefin copolymer can be used for the innermost layer 24a. In this embodiment, EVOH is used as the innermost layer 24a.

In particular, by using EVOH, polyamide, or the like for the innermost layer 24a, it is possible to improve the gas barrier properties of the laminated container 100 and suppress deterioration of the contents due to exposure to air. Further, a resin layer having light-shielding properties may be laminated instead of or together with the gas barrier resin layer. Furthermore, an additional resin layer may be provided on the radially inner side of the innermost layer 24a.

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

The material of the outermost layer 24c includes, for example, a polyolefin resin such as polyethylene (PE) or polypropylene (PP), or a polyester such as polyethylene terephthalate (PET), polycyclohexylene dimethylene terephthalate (PCT), or polyethylene naphthalate (PEN). A resin whose main material is a type resin can be used. By incorporating one or more of paper (cellulose fine particles), calcium carbonate, and starch into the main material, the proportion of combustible waste components in the release layer 24 is increased from 25% by weight to 45% by weight. Adjusted to the following range. The combustible waste component referred to here is not a synthetic resin derived from petroleum, but a component that can be disposed of and burned as paper. Combustible waste components are not necessarily limited to paper (cellulose particles), calcium carbonate, and starch.

Note that the outermost layer 24c may be composed of two or more resin layers, and it is sufficient that at least one of the plurality of resin layers contains the above-mentioned combustible waste component.

Further, in the present embodiment, the thickness of the peeling layer 24 including the innermost layer 24a, the adhesive layer 24b, and the outermost layer 24c is 200 μm or more and 300 μm or less. By setting the thickness of the release layer 24 to 200 μm or more, the moldability of the release layer 24 and the releasability to the bottle layer 22 can be improved even if the combustible waste component is kneaded into the release layer 24 in a range of 25% by weight or more and 45% by weight or less. can be secured. Furthermore, by setting the thickness of the release layer 24 to 300 μm or less, the amount of resin material used can be suppressed in consideration of the environment.

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 an in-mold label made of paper, and can be attached to the outer surface of the release layer 24 during in-mold molding. The label layer 26 contains 70% by weight or more and 100% by weight or less of a paper component which is combustible waste. As described above, in this embodiment, the label layer 26 of the label portion 28 contains a large amount (70% by weight or more) of the paper component, which is a combustible waste component, so that the proportion of the combustible waste component in the label portion 28 is increased to 51% by weight or more. It is increasing to 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 ratio of the paper component, which is combustible waste, in the release layer 24 may be 51% by weight or more.

The label layer 26 of this embodiment is a label member formed as an in-mold label when the bottle layer 22 and the release layer 24 are extruded and blow-molded, and contains a paper component that is combustible waste of 70% by weight or more and 100% by weight or less. Contains. In this embodiment, as will be described later, the label layer 26 is placed in advance in a blow molding mold for extrusion blow molding the bottle layer 22 and the release layer 24, and the outermost layer 24c of the release layer 24 is formed by extrusion blow molding. Laminated on. Note that a new adhesive layer may be provided between the outermost layer 24c of the release layer 24 and the label layer 26, or as described in Japanese Patent No. 6120755, the label may be separated by intertwining the edge of the label with the surface of the release layer 24. The attachment strength of layer 26 may be increased.

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, more preferably 100 μm or more and 250 μm or less.

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

Furthermore, by setting the thickness of the label layer 26 to 300 μm or less, the bending rigidity can be kept low, so even if the area where the label layer 26 is provided has a curved shape, the label layer 26 does not return to its original shape from the curved shape. The restoring force does not affect the moldability of the body portion 20. By setting the thickness of the label layer 26 to 250 μm or less, it is possible to more effectively suppress the restoring force of the label layer 26 from affecting the moldability of the body portion 20.

In this embodiment, the label layer 26 preferably has an area that is 40% or more of the surface area of the laminated container 100. With such a configuration, under the condition that the combustible waste component in the release layer 24 is 35% by weight, the combustible waste component in the label portion 28 can be ensured to be 51% by weight or more. Moreover, 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 the blow molding die, making it easier to form an in-mold label.

In this embodiment, by increasing the proportion of combustible waste components in the label portion 28 to 51% by weight or more, the label portion 28 that has been peeled off from the bottle layer 22 can be disposed of as paper. With such a configuration, the bottle layer 22 after the label part 28 has been peeled off may be collected and recycled as, for example, a PET bottle, while the label part 28 can be disposed of as paper, so it can be discarded as non-combustible waste. The laminated container 100 after use can be processed without causing any damage.

Note that as a method for increasing the proportion of combustible waste components in the label portion 28 to 51% by weight or more, it is also possible to increase the proportion of combustible waste components in the release layer 24 to 51% by weight or more without using the label layer 26. . However, when the proportion of combustible waste components in the release layer 24 exceeds 45% by weight, the moldability of the release layer 24 and the releasability from the bottle layer 22 tend to decrease as described below. In the present embodiment, while suppressing the proportion of combustible waste components in the release layer 24 to 45% by weight or less, a label layer 26 containing paper components of 70% to 100% by weight is laminated on the radially outer side of the release layer 24. Accordingly, the proportion of combustible waste components in the entire label portion 28 that is peeled off from the bottle layer 22 is set to be 51% or more. With this configuration, moldability and peelability of the release layer 24 can be ensured, and the label part 28 peeled off from the bottle layer 22 can be disposed of as paper.

Although the release layer 24 of this embodiment is configured such that the outermost layer 24c is laminated on the outer side of the innermost layer 24a via the adhesive layer 24b, the present invention is not limited to this embodiment. An adhesive resin may be mixed into at least one of the innermost layer 24a and the outermost layer 24c, and the outermost layer 24c may be bonded and laminated to the innermost layer 24a without using the adhesive layer 24b.

Moreover, the peeling layer 24 may be comprised only of the innermost layer 24a or the outermost layer 24c. In this case, the combustible waste component can be incorporated into the innermost layer 24a or the outermost layer 24c constituting the release layer 24.

In this embodiment, the outer surface of the label layer 26 may be decorated by, for example, printing, transfer, vapor deposition, painting, or adding a coloring material.

In this embodiment, for example, when inkjet printing, which is easy to print on thinned containers, is used, the labels can be separated by peeling and removing the label part 28 from the bottle layer 22 at the time of sorting. Therefore, it is possible to achieve both a reduction in environmental load due to thinner walls and easy separation of containers. Furthermore, when silk printing is used for decoration, the printing can sometimes be removed by washing, but in this embodiment there is no need for washing.

In this embodiment, the entire area of the peeling layer 24 is configured to be peelable from the bottle layer 22. However, the entire region of the peeling layer 24 does not necessarily need to be peelable from the bottle layer 22. For example, the release layer 24 is 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 are partially separated by complex irregularities such as the male threaded portion 10b of the mouth 10. It may be configured to be fixed. In this case, the label layer 26 is preferably laminated in an area of the release layer 24 that can be removed from the bottle layer 22. Furthermore, the release layer 24 and the bottle layer 22 may be removably adhered to each other with an adhesive or the like.

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

Alternatively, a through hole may be formed in the outer surface of the mouth 10, bottom 40, etc. of the laminated container 100, and the release layer 24 may be easily peeled off from the bottle layer 22 by sending air through the through hole.

The laminated container 100 having the configuration shown in FIGS. 1 to 3 can be manufactured, for example, by extrusion blow molding. When manufacturing the laminated container 100, first, the label layer 26 is placed near the wall surface within the blow molding die (step S101 in FIG. 4). The label layer 26 placed within the blow molding mold is fixed within the blow molding mold by means such as vacuum suction.

Next, a laminated parison in which a resin layer constituting the bottle layer 22 (container portion) and a 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 laminated. At the same time as extrusion blow molding, a label layer 26 is laminated as an in-mold label on the outside of the release layer 24 (step S103 in FIG. 4). As described above, the label layer 26 can be formed by providing a new adhesive layer between the outermost layer 24c of the release layer 24 and the label layer 26, by applying an adhesive to the inner surface of the label layer 26, or by applying an adhesive to the inner surface of the label layer 26, or by applying adhesive to the inner surface of the label layer 26, or by applying adhesive to the inner surface of the label layer 26. The attachment strength may be increased by intertwining the surface of the release layer 24 with the surface of the release layer 24.

When the extrusion blow molding is completed, the vacuum adsorption of the label layer 26 is stopped, the mold is opened, and the laminated container 100 is taken out, thereby completing the production.

The laminated structure of the bottle layer 22 and the release layer 24 can be obtained not only by extrusion blow molding but also by stretch blow molding a laminated preform in which the bottle layer 22 and the release layer 24 are laminated, and by in-mold molding the label layer 26. It may also be formed.

As described above, the laminated container 100 according to the present embodiment includes a body 20 that accommodates the contents, an opening 10 connected to the upper end of the body 20, and a bottom 40 that closes the lower end of the body 20. a container part (bottle layer 22) having a container part (bottle layer 22), and a label part 28 that covers at least a part of the body part 20 from the outside; The label portion 28 contained a combustible waste component in an amount of 51% by weight or more, and the thickness of the release layer 24 was 200 μm or more and 300 μm or less. By adopting such a configuration, separation is completed by peeling off the label portion 28 from the container portion (bottle layer 22) after the contents have been used, making it easy to recycle the container portion and discard the label portion 28 as paper waste. can do.

Further, 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, by laminating the label layer 26 as an in-mold label on the release layer 24, the laminated container 100 can be formed only by the bottle molding process. The manufacturing cost of the laminated container 100 can be suppressed. Moreover, the moldability of the release layer 24 and the releasability with respect to the bottle layer 22 can be ensured.

In the present 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 It was configured to cover 40% or more. By adopting such a configuration, the ratio of combustible waste components in the entire label part 28 is set to 51% or more without reducing the moldability of the release layer 24 or the peelability from the container part, and the label part 28 can be disposed of as paper. be able to.

Further, in this embodiment, the thickness of the label layer 26 is configured 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 combustible waste components in the entire label portion 28, and to effectively prevent the restoring force of the label layer 26 from affecting the formability of the body portion 20. Can be suppressed.

Further, in this embodiment, a container section (bottle layer 22 ) and a label part 28 that covers at least a part of the body part 20 from the outside, the method includes the steps of: arranging the label layer 26 in a blow molding mold; The step includes blow molding the container part and a release layer 24 laminated on the outside of the container part, and laminating a label layer 26 as an in-mold label on the outside of the release layer 24, and the label part 28 is made of combustible waste. The peeling layer 24 was configured to have a thickness of 200 μm or more and 300 μm or less, including 51% by weight or more of the components. By adopting such a configuration, separation is completed by peeling off the label portion 28 from the container portion (bottle layer 22) after the contents have been used, making it easy to recycle the container portion and discard the label portion 28 as paper waste. can do. 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 by the bottle molding process, so the manufacturing cost of the laminated container 100 having the label layer 26 containing a paper component is reduced. can be suppressed. Moreover, the moldability of the release layer 24 and the releasability with respect to the bottle layer 22 can be ensured.

Although the present disclosure has been described based on the drawings and examples, it should be noted that those skilled in the art can easily make various changes and modifications based on the present disclosure. Therefore, it should be noted that these variations and modifications are included within the scope of the present invention. For example, functions included in each component can be rearranged so as not to be logically contradictory, and a plurality of components can be combined into one or divided. It is to be understood that these are also included within the scope of the present invention.

For example, in the present embodiment, the external threaded portion 10b is provided on the outer peripheral surface of the mouth portion 10 so that a mounting cap, a pump, etc. can be mounted by threaded engagement, but the present invention is not limited to this embodiment. The mouth portion 10 may be provided with an annular protrusion for attaching a mounting cap, a pump, etc. by plugging engagement, instead of or together with the male threaded portion 10b. Alternatively, the mouth portion 10 may be configured without an engaging portion.

Further, in this embodiment, an example was shown in which the laminated container 100 is formed by blow molding a laminated parison formed by extrusion molding, or by stretch blow molding a laminated preform. It is not limited to this aspect. The laminated container 100 may be formed, for example, by two-color molding, or by setting a plurality of preforms in a mold and performing stretch blow molding.

Further, the present disclosure can be widely applied not only to the laminated container 100 in which the body 20 has a substantially cylindrical shape as shown in FIG. 1, but also to square containers, pouch containers, cup containers, and the like.

In order to confirm the moldability of the laminated container 100 of the present disclosure and the releasability of the release layer 24 from the bottle layer 22, Examples 1 to 7 in which the proportion of combustible waste components (paper) in the release layer 24 were changed (see Table 1) ) was prototyped and evaluated. Further, conditions common to Examples 1 to 7 are shown in Table 2.

According to the evaluation results shown in Table 1, by suppressing the proportion of the paper component in the release layer 24 to 45% by weight or less, the moldability and peelability of the release layer 24 can be maintained favorably. 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 (problem with moldability), and the release layer 24 There have been cases where the bottle layer 22 is torn when it is peeled off (releasability problem), but by suppressing the proportion of paper components in the release layer 24 to 45% by weight or less, the occurrence of the above problem can be prevented. I was able to do that.

Furthermore, by setting the paper component ratio in the release layer 24 to 25% by weight or more (that is, by setting the area of the label layer 26 to 70% or less of the surface area of the laminated container 100), the paper ratio in the label portion 28 can be increased to 51% by weight. The ratio of the area of the label layer 26 to the surface area of the laminated container 100 to achieve the above can be set to 69.6% or less, which is an easily realized ratio. Furthermore, as shown in Table 1, by setting the proportion of the paper component in the release layer 24 to 25% by weight or more, the label layer 26 can be made large enough to be inserted into the blow molding die. When the ratio of the paper component in the release layer 24 was 20% by weight (Example 1), the surface area of the label layer 26 was so large that it could not be inserted into the blow molding mold.

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

According to Table 3, if the thickness of the label layer 26 is 300 μm or less (Examples 8 and 9), the label layer 26 can be inserted into a blow molding mold and the label layer 26 can be laminated as an in-mold label. was possible. Note that the remark in Embodiment 9 that "only the shape of the body part that is close to a flat surface can be inserted" means that when the body part 20 has a curved surface with a small radius of curvature, the restoring force of the label layer 26 allows it to be inserted into the curved surface. This means that it could not be maintained. On the other hand, when the thickness of the label layer 26 was 480 μm (Example 10), the body 20 ruptured at the edge of the label layer 26 and the laminated container 100 could not be formed. This is considered to be because in Example 10, the label layer 26 had high bending rigidity, and concentrated stress was generated in the body part 20 due to the restoring force that tried to return to the original shape.

According to the present disclosure, it is possible to propose a stacked container 100 in which the label portion 28 can be easily disposed of as paper waste.

10 Mouth part 10a Opening 10b Male screw part 20 Body part 22 Bottle layer (container part)
24 Peeling layer 24a Innermost layer 24b Adhesive layer 24c Outermost layer 26 Label layer 28 Label part 30 Shoulder part 40 Bottom part 100 Laminated container O Central axis S Accommodation space

Claims (5)

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;
The label part has a release layer that is removably laminated on the outermost surface of the container part, and the label part contains 51% by weight or more of a combustible waste component,
A laminated container characterized in that the thickness of the peeling layer is 200 μm or more and 300 μm or less. The laminated container according to claim 1, wherein the label portion has a label layer laminated on the outer surface of the release layer. The release layer contains 25% by weight or more and 45% by weight or less of a combustible waste component,
The laminated container according to claim 2, wherein 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. The laminated container according to claim 2 or 3, wherein the label layer has a thickness of 50 μm or more and 300 μm or less. 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 method for manufacturing a laminated container comprising: a label portion that covers at least a portion of the body portion from the outside;
placing a label layer within the blow mold;
blow-molding the container part and a release layer laminated on the outside of the container part in the blow molding mold, and laminating the label layer as an in-mold label on the outside of the release layer. ,
The label portion contains 51% by weight or more of combustible waste components,
A method for manufacturing a laminated container, characterized in that the thickness of the peeling layer is 200 μm or more and 300 μm or less.