JP2005001689A - Multi-layered structure and multi-layered container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily recover the gas barrier property degraded by hot water treatment. <P>SOLUTION: A multi-layered container 10 formed of a multi-layered structure 10a with a plurality of stacked resin layers has a lamination structure comprising a plurality of gas barrier property thermoplastic resin layers gb1 and gb2, at least one olefin resin intermediate layer ol1 provided between the gas barrier property thermoplastic resin layers gb1 and gb2, and at least one olefin resin outer surface layers ol2 and ol3 provided on the outer surface sides of the barrier property thermoplastic resin layers gb1 and gb2 on both outer sides out of the barrier property thermoplastic resin layers gb1 and gb2. Since the olefin resin intermediate layer ol1 functions as a water barrier layer, the gas barrier property thermoplastic resin layer gb2 on the outermost side hardly receives water from the inner surface side, and is easily dried. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a multilayer structure and a multilayer container, and more particularly, to a multilayer structure and a multilayer container that can easily recover a gas barrier property that has been lowered by hot water treatment.
[0002]
[Prior art]
Conventionally, as packaging containers for foods or beverages, from the viewpoints of storage stability, sealing properties, gas barrier properties, and heat resistance of contents, a laminated sheet formed by laminating a plurality of resin layers is formed by vacuum forming, vacuum pressure forming, etc. A multi-layer resin container molded in (1) is used.
Here, the laminated sheet is made of, for example, polyolefin / ethylene vinyl alcohol copolymer / polyolefin, and generally has a thickness of about 0.3 to 1.0 mm.
[0003]
In addition, the multilayer container for holding processed foods is subjected to hot water sterilization treatment such as boil sterilization and retort sterilization, and depending on the hot water sterilization temperature, usually from polypropylene / ethylene vinyl alcohol copolymer / polypropylene. A laminated structure is used.
[0004]
In addition, the multilayer container is not limited to a pure one made of resin, and from the viewpoint of environmental problems, a composite container formed by joining a paper member outer container to a plastic member inner container is considered. For example, a composite container having hot water resistance in which the strength of the container is improved by using a paper member as resin-impregnated paper is known (for example, see Patent Document 1).
[0005]
[Patent Document 1]
JP-A-2001-270563 [0006]
[Problems to be solved by the invention]
However, the multilayer container as described above has a sufficient gas barrier property in a dry state, but the gas barrier property is significantly lowered in a wet state immediately after the hot water sterilization treatment.
[0007]
Specifically, the plastic multi-layer container is greatly deteriorated in gas barrier properties due to intrusion of moisture into the container main body during and immediately after the hot water treatment process such as boil cooking sterilization or retort cooking sterilization. Specifically, moisture enters the ethylene vinyl alcohol copolymer as the gas barrier resin layer, and the gas barrier property is remarkably lowered.
[0008]
Here, the wet multilayer container is dried from the outside of the container, but is difficult to dry due to the moisture of the contents. For example, in order to dry the multilayer container and restore the gas barrier property, it is necessary that moisture that has entered the polyolefin resin layer on the innermost surface of the container is released to the outside of the container through the gas barrier resin layer.
[0009]
For this reason, recovery of the gas barrier property of the gas barrier resin layer requires significantly more time and energy than apparent drying of the container.
[0010]
On the other hand, various packaging materials whose gas barrier properties do not deteriorate even after hot water treatment have been proposed. However, this type of packaging material has a problem that it cannot be used for vacuum forming, vacuum pressure forming, etc., because the gas barrier property is small but the moldability is low.
[0011]
The present invention has been made in consideration of the above circumstances, and has a moldability that can be molded into a multilayer container, and in the molded multilayer container, a multilayer structure that can easily recover a gas barrier property that has been lowered by hot water treatment. It is to provide.
[0012]
Another object of the present invention is to provide a multilayer container that can easily recover the gas barrier property that has been lowered by the hot water treatment.
[0013]
[Means for Solving the Problems]
A first invention is a multilayer structure in which a plurality of resin layers are laminated, and each of the resin layers is provided between the plurality of gas barrier thermoplastic resin layers and each of the gas barrier thermoplastic resin layers. In addition, at least one olefin resin intermediate layer and at least one olefin resin outer surface provided on the outer surface side of each gas barrier thermoplastic resin layer on both outer sides of the gas barrier thermoplastic resin layers. And a multilayer structure.
[0014]
Here, since each resin layer consists of a thermoplastic resin or an olefin resin, it has the moldability which can be shape | molded in a multilayer container.
In addition, since it has a laminated structure in which a plurality of gas barrier thermoplastic resin layers are sandwiched between olefin resin layers, the olefin resin intermediate layer is used as a moisture barrier layer when it is molded into a multilayer container and dried after hydrothermal treatment. It functions and suppresses the passage of moisture from the inner surface side to the outer surface side than the olefin-based resin intermediate layer. For this reason, at least the outermost gas-barrier thermoplastic resin layer hardly receives moisture from the inner surface side more than that, so that it becomes easy to dry.
[0015]
Therefore, it has the moldability which can be shape | molded in a multilayer container, and can reduce | restore easily the gas barrier property reduced by the hot water process in the shape | molded multilayer container.
[0016]
According to a second invention, in the first invention, each of the gas barrier thermoplastic resin layers is a multilayer structure made of EVOH (ethylene-vinyl acetate saponified product).
[0017]
Thereby, in addition to the effect | action of 1st invention, since EVOH is sensitive to hygroscopicity / drying property, the drying after a hot-water process can be performed more effectively.
[0018]
According to a third invention, in the first or second invention, the olefin-based resin intermediate layer is a multilayer structure made of an adhesive resin.
Thereby, in addition to the effect | action of 1st or 2nd invention, the multilayered structure formed into a sheet by multilayer coextrusion molding can be obtained.
[0019]
4th invention is the invention in any one of 1st-3rd. Among the olefin resin outer surface layers provided in the both outer sides, one olefin resin outer surface layer on the outermost surface side is made of an adhesive resin. A multilayer structure.
Thereby, in addition to the effects of the first to third inventions, it is possible to provide a multilayer structure that can be joined to another material such as paper, and to form a composite container with any different material such as paper. A molded member or the like can be provided.
[0020]
A fifth invention is a multilayer container formed from the multilayer structure according to any one of the first to fourth inventions.
Thus, there is provided a multilayer container that exhibits the effects of the first to fourth inventions and that can be molded by any molding method such as vacuum molding, pressure molding, vacuum pressure molding, extrusion blow molding, pouch molding, and the like. Can do.
[0021]
A sixth aspect of the invention is the heat-resistant water-based paper according to the fifth aspect of the invention, which is bonded to the outside of the multilayer container main body, does not peel off in hot water at 135 ° C. or less, and does not cause appearance defects such as wet wrinkles after drying It is a multilayer container provided with the exterior container which consists of.
Thereby, in addition to the effect | action of 5th invention, the multilayer container which can reduce the usage-amount of the plastic material of each resin layer can be provided with the structure used as the composite container with heat-resistant water paper.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
FIG. 1 is a cross-sectional view showing the configuration of the multilayer structure according to the first embodiment of the present invention. The multilayer structure 10a includes a plurality of gas barrier thermoplastic resin layers gb1 and gb2, and at least one or more olefin resin intermediate layers ol1 provided between the gas barrier thermoplastic resin layers gb1 and gb2, Of the barrier thermoplastic resin layers gb1 and gb2, a laminate comprising at least one or more olefin-based resin outer surface layers ol2 and ol3 provided on the outer surface sides of the respective barrier thermoplastic resin layers gb1 and gb2 on both outer sides. It has a structure.
[0023]
Here, the phrase “plurality (gas barrier properties ...)” literally means “two or more layers”. For example, as shown in a modified example in FIG. 2, it means that four gas barrier thermoplastic resin layers gb1 and gb2 may be used, such as a multilayer structure 10b formed by laminating the multilayer structure 10a. . Needless to say, the phrase “plurality (gas barrier property...)” Is not limited to two layers or four layers, and may be any number of layers.
[0024]
Similarly, the phrase “at least one layer (olefin-based ...)” literally means “one or more layers”. For example, as shown in the modified example of FIG. 2, it means that two olefin resin intermediate layers ol3 ′ and ol2 ′ may be used. However, in the following description, the configuration shown in FIG. 1 is described as a representative example.
Among the multilayer structure 10a, a method of obtaining a laminated structure of the gas barrier thermoplastic resin layer gb1 / polyolefin-based resin intermediate layer ol1 / gas barrier thermoplastic resin layer gb2 is a dry laminate method, a wet laminate method, a coextrusion method, etc. A well-known method is applicable. Further, an adhesive or the like may be interposed between the respective layers.
[0025]
The multilayer structure 10a can be molded (molded) by any molding method such as vacuum molding, pressure molding, vacuum pressure molding, extrusion blow molding, pouch shape, or the like.
[0026]
For example, the multilayer structure 10a has an arbitrary shape such as a bottle shape as shown in the external view of FIG. 3 and the longitudinal sectional view of FIG. 4, or a cup shape as shown in the external view of FIG. 5 and the longitudinal sectional view of FIG. The multilayer container 10 can be molded.
[0027]
The multilayer container 10 formed by molding the multilayer structure 10a is suitable for applications that require gas barrier properties, water vapor barrier properties, fragrance retention, and the like as containers for boiled sterilized cooked foods and retort cooked sterilized foods.
[0028]
Next, the operation of the multilayer structure and multilayer container configured as described above will be described.
Now, it is assumed that the multilayer structure 10a shown in FIG. 1 is formed into the multilayer container 10 shown in FIG. 3 to FIG. 4 or FIG. 5 to FIG. It is assumed that the multilayer container 10 is filled with contents such as liquid food and sealed with a lid material (not shown).
[0029]
Subsequently, the multilayer container 10 is subjected to a hot water treatment process such as a retort sterilization treatment. Here, in the multi-layer container 10, moisture penetrates during the hot water treatment as in the conventional container.
[0030]
However, in the multilayer container 10, the olefin-based resin intermediate layer ol1 functions as a moisture-proof layer (moisture barrier layer) in the drying step. For this reason, the gas barrier thermoplastic resin layer gb2 outside the container is actively promoted to dry moisture. The reason is that the effect of moisture from the inside of the container is prevented by ol2, and the moisture contained in gb1 is prevented from being dried by ol1, so that only ol3 prevents the drying of gb2.
[0031]
On the other hand, the gas barrier thermoplastic resin layer gb1 on the inner surface side of the container acts primarily as a water retaining layer because of its ability to absorb water, thereby temporarily delaying the drying of the olefin resin layer ol2 provided on the inner surface.
[0032]
Therefore, in the drying process, the gas barrier thermoplastic resin layer gb2 outside the container is easy to dry, so that the recovery of the gas barrier property is remarkably quick and can be recovered to a higher level.
[0033]
As for the multilayer structure 10a or the multilayer container 10 as described above, the thicker the thickness, the more effective the gas barrier property can be recovered. The reason is that the thicker the olefin-based resin intermediate layer ol1 can suppress the release of moisture from the container inner surface gb1, and the ol3 that prevents drying of ol1 and gb2 can be made thinner. Therefore, the gas barrier thermoplastic resin layer on the outer surface side of the container This is because drying of gb2 is promoted. The thickness of the multilayer structure 10a is not limited to a specific value, but is preferably 70 μm or more from the viewpoint of obtaining a remarkable recovery effect.
[0034]
As described above, according to the present embodiment, each of the resin layers ol1 to ol3, gb1, and gb2 of the multilayer structure 10a is made of a thermoplastic resin or an olefin-based resin. Have.
[0035]
In addition, since the olefin-based resin intermediate layer ol1 functions as a moisture barrier layer, the outermost gas barrier thermoplastic resin layer gb2 hardly receives moisture from the inner surface side, and thus is easily dried.
[0036]
Therefore, the multilayer structure 10a of the present embodiment has a moldability that can be formed into the multilayer container 10, and in the molded multilayer container 10, it is possible to easily recover the gas barrier property that has decreased due to the hot water treatment. In addition, the multilayer container 10a formed from the multilayer structure 10a naturally has the same gas barrier property recovery effect.
[0037]
(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. 1 and 3 to 6 described above.
This embodiment is a specific example of the first embodiment, and has a configuration in which the gas barrier thermoplastic resins gb1 and gb2 of the multilayer structure 10a and the multilayer container 10 are EVOH (EVOH: ethylene-vinyl acetate saponified product). .
[0038]
With the above configuration, in addition to the effects of the first embodiment, it is possible to obtain the multilayer structure 10a and the multilayer container 10 that are excellent in transparency at the time of visual recognition and barrier properties at the time of drying.
[0039]
Furthermore, because of the sensitivity of EVOH to hygroscopicity / dryability, the drying process after hydrothermal treatment can be more effectively carried out, and the gas barrier property can be recovered significantly faster and can be recovered to a higher level. .
[0040]
(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIGS. 1 and 3 to 6 described above.
This embodiment is a specific example of the first or second embodiment, and has a configuration in which the multilayer structure 10a and the olefin resin intermediate layer ol1 of the multilayer container 10 are adhesive resins.
[0041]
With the above configuration, in addition to the effects of the first or second embodiment, a multilayer structure 10a formed into a sheet by multilayer coextrusion molding can be obtained.
[0042]
Furthermore, since this adhesive resin is a polyolefin-maleic acid graft-modified resin, the effect as a barrier layer against moisture on the inner surface of the container when the container is wet can be increased, so that the gas barrier thermoplastic resin layer gb2 on the outer side of the container Drying and gas barrier property recovery can be accelerated.
[0043]
Further, when the multilayer structure 10a is obtained, the multilayer container 10 can be obtained by simultaneously forming into a container shape. At the same time, when the multilayer container 10 is obtained, any molding method such as an extrusion blow molding method can be applied.
[0044]
(Fourth embodiment)
FIG. 7 or FIG. 8 is a longitudinal sectional view showing the configuration of the multilayer container according to the fourth embodiment of the present invention.
This embodiment is a modification of the first to third embodiments, and is bonded to the outside of the multilayer container 10 described above, and does not peel off in hot water at 135 ° C. or less, and is wet after drying. A composite multilayer container 30 including an exterior container 20 made of a heat-resistant water-paper layer 20a that does not cause an appearance defect is provided.
[0045]
Here, the heat-resistant water-resistant paper layer 20a that does not peel in hot water of 135 ° C. or less and does not cause poor appearance such as wet wrinkles after drying is as described by the present inventor in Patent Document 1 described above. For example, it can be obtained by impregnating a paper member with a polyisocyanate resin or a polyolefin resin.
[0046]
However, the heat resistant water paper layer 20a is not limited to the polyisocyanate resin or the polyolefin resin impregnated paper, and any heat resistant water paper can be used. The heat-resistant water paper includes all fiber structures made of pulp or the like having heat-resistant water, and is not limited to the so-called heat-resistant water paper.
[0047]
In addition, the term “appearance defects such as wetting wrinkles” includes only the heat of hot water or deformation due to water, and specifically includes melting or shrinking due to heat in addition to wrinkles due to water. However, deformation and damage due to impact are not included.
[0048]
On the other hand, from the viewpoint of easily joining the outer packaging container 20, the multilayer structure 10 a adheres to the outermost olefin resin outer surface layer ol 3 in the multilayer container 10 among the outer olefin resin outer surface layers ol 2 and ol 3. It is made of resin.
[0049]
With the configuration as described above, in addition to the effects of the first to third embodiments, a multilayer container 30 having excellent hot water resistance in which the exterior container 20 made of heat-resistant water paper and the interior-side multilayer container 10 are bonded is obtained. be able to.
[0050]
In addition, by forming a composite container with heat-resistant water paper, the multilayer structure 10a mainly composed of paper having excellent barrier properties capable of boil sterilization and retort sterilization while reducing the use of plastic materials to the limit A container 30 can be provided.
[0051]
Further, since the outermost olefin resin layer ol3 is made of an adhesive resin in the multilayer structure 10a, it can be bonded to another material such as paper, and a composite container with different materials such as paper is obtained. For example, a molded member can be obtained.
[0052]
Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.
[0053]
【Example】
Hereinafter, each example of the present invention is described in detail.
(Example 1)
Example 1 corresponds to the first to third embodiments. That is, it corresponds to the embodiment of the multilayer container 10 that does not have the outer container 20.
A formable sheet as the multilayer structure 10a was prepared by coextrusion molding.
[0054]
This formable sheet has a configuration of PP 300 μm / adhesive resin 40 μm / EVOH 50 μm / adhesive resin 120 μm / EVOH 50 μm / adhesive resin 40 μm / PP 300 μm, and has a total thickness of 900 μm.
[0055]
Using this molding sheet, a cup-type multilayer container 10 having a full injection capacity of 350 ml was prototyped by vacuum molding. This multilayer container 10 has a minimum thickness of 250 μm.
[0056]
As a result of measuring the oxygen permeation amount at the time of drying of the cup-shaped multilayer container 10 by the Mocon method (ASTM F-1307), it was 0.005 ml / 24 h / 0.21 atm.
[0057]
The cup-shaped multilayer container 10 was filled with the contents and subjected to a retort sterilization treatment at 121 ° C. for 30 minutes. Thereafter, when the oxygen intrusion amount of the multilayer container 10 immediately after the retort sterilization treatment was measured, 4 ml of intrusion was observed.
[0058]
In addition, after one day of normal temperature drying from retort sterilization, the oxygen intrusion amount of the multilayer container 10 was 4.5 ml. Furthermore, after 7 days from room temperature drying after retort sterilization, the oxygen intrusion amount of the multilayer container 10 was 5 ml.
[0059]
(Comparative Example 1)
In Comparative Example 1, a cup-type multilayer container was prepared from a molding sheet having a gas barrier thermoplastic resin layer as one layer.
[0060]
The molding sheet of Comparative Example 1 has a configuration of PP 300 μm / adhesive resin 100 μm / EVOH 100 μm / adhesive resin 100 μm / PP 300 μm, and has a total thickness of 900 μm by co-extrusion molding. The total thickness of Comparative Example 1 and the thickness of the barrier thermoplastic resin layer (EVOH) are set to the same total values as in Example 1.
[0061]
A cup-shaped container having a full injection capacity of 350 m1 having the same shape as that of Example 1 was prototyped by vacuum-forming this molding sheet. The minimum value of the wall thickness of the cup-type container is the same value as in Example 1.
[0062]
The amount of oxygen permeation when the cup-type container of Comparative Example 1 was dried and the amount of oxygen permeation immediately after the retort sterilization treatment at 121 ° C. for 30 minutes were the same as those in Example 1.
On the other hand, after 1 day of normal temperature drying from retort sterilization, the oxygen intrusion amount of the cup-type container was larger than that of Example 1 and was 6 ml. Furthermore, after 7 days of room temperature drying after retort sterilization, the oxygen intrusion amount of the cup-type container was larger than that of Example 1 and was 8 ml.
[0063]
(Example 2)
Example 2 corresponds to the fourth embodiment. That is, it corresponds to the embodiment of the multilayer container 30 having the outer container 20.
[0064]
A formable sheet as the multilayer structure 10a was prepared by coextrusion molding.
[0065]
This formable sheet has a structure of PP 100 μm / adhesive resin 30 μm / EVOH 20 μm / adhesive resin 30 μm / EVOH 20 μm / adhesive resin 50 μm, and has a total thickness of 250 μm. Since it is used for a composite container, the amount of plastic material used is reduced.
[0066]
Using this molding sheet, a cup-shaped multilayer container 30 having a full injection capacity of 300 ml was prototyped using a vacuum molding die in which an outer container 20 previously made with heat-resistant water paper 20a was mounted in the die.
[0067]
In this molding sheet, the outer PP surface is the inner side of the container, and the adhesive resin surface is bonded to the outer container 10 simultaneously with the vacuum molding. The multilayer container 30 has a minimum wall thickness of 100 μm.
[0068]
The outer container 20 is composed of a heat resistant water paper layer 20a having a basis weight of 300 g / m 2 and occupies 70% by weight of the obtained multilayer container 30.
[0069]
As a result of measuring the oxygen permeation amount at the time of drying of the multilayer container 30 by the Mokon method (ASTM F-1307), it was 0.006 ml / 24 h / 0.21 atm.
[0070]
As a result of filling the multilayer container 30 with the contents and measuring the oxygen intrusion amount immediately after the retort sterilization treatment at 121 ° C. for 30 minutes, 8.0 ml intrusion was observed.
Moreover, after carrying out normal temperature drying from retort sterilization on the 1st, the oxygen permeation amount of the multilayer container 30 was 9 ml. Furthermore, after 7 days of room temperature drying after retort sterilization, the oxygen intrusion amount of the multilayer container 30 was 10 ml.
[0071]
(Comparative Example 2)
In Comparative Example 2, a cup-shaped composite container was prepared from a molding sheet having a gas barrier thermoplastic resin layer as one layer.
[0072]
The molding sheet of Comparative Example 2 has a structure of PP 100 μm / adhesive resin 20 μm / EVOH 40 μm / adhesive resin 20 μm / PP 20 μm / adhesive resin 50 μm, and has a total thickness of 250 μm by co-extrusion molding. The total thickness of Comparative Example 2 and the thickness of the barrier thermoplastic resin layer (EVOH) are set to the same total values as in Example 2.
[0073]
A cup-type container having a full capacity of 300 m1 having the same shape as that of Example 2 was prototyped by using a vacuum forming mold in which an outer container in which the forming sheet was previously made of heat-resistant water paper was mounted in the mold. The minimum value of the wall thickness of the cup-type composite container is the same value as in Example 2. Similarly, the weight of the outer container (heat-resistant water paper) and the weight ratio with respect to the composite container are the same values as in Example 2.
[0074]
The amount of oxygen permeation during drying of the cup-type composite container of Comparative Example 2 was the same as that of Example 2.
[0075]
On the other hand, as a result of filling the composite container with the contents and measuring the oxygen intrusion amount immediately after the retort sterilization treatment at 121 ° C. for 30 minutes, more than Example 2 and 10 ml intrusion was observed.
[0076]
Moreover, after carrying out normal temperature drying from retort sterilization on the 1st, the oxygen penetration amount of the composite container was larger than Example 1, and was 12 ml. Furthermore, after 7 days of room temperature drying after retort sterilization, the oxygen intrusion amount of the cup-type container was 14 ml, which was larger than that in Example 2.
[0077]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a multilayer structure that has moldability that can be molded into a multilayer container and that can easily recover the gas barrier property that has been lowered by the hot water treatment in the molded multilayer container. In addition, it is possible to provide a multilayer container that can easily recover the gas barrier property that has been lowered by the hot water treatment.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a configuration of a multilayer structure according to a first embodiment of the present invention.
FIG. 2 is a sectional view showing a modification of the multilayer structure in the embodiment.
FIG. 3 is an external view when the multilayer container in the same embodiment has a bottle shape.
4 is a longitudinal sectional view of the multilayer container of FIG.
FIG. 5 is an external view when the multilayer container in the embodiment is cup-shaped.
6 is a longitudinal sectional view of the multilayer container of FIG.
FIG. 7 is a longitudinal sectional view when a multilayer container according to a fourth embodiment of the present invention has a bottle shape.
FIG. 8 is a longitudinal sectional view when the multilayer container is cup-shaped in the same embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10a ... Multilayer structure, gb1, gb2 ... Gas barrier thermoplastic resin layer, ol1 ... Olefin resin intermediate layer, ol2, ol3 ... Olefin resin outer surface layer, 20a ... Heat-resistant water paper layer, 20 ... Exterior container, 30 ... Multilayer container.

Claims (6)

In a multilayer structure in which a plurality of resin layers are laminated,
Each of the resin layers is
A plurality of gas barrier thermoplastic resin layers;
At least one olefin-based resin intermediate layer provided between the gas barrier thermoplastic resin layers;
Of each of the gas barrier thermoplastic resin layers, at least one or more olefin-based resin outer surface layers provided on the outer surface side of the gas barrier thermoplastic resin layers on both outer sides,
A multilayer structure characterized by comprising: The multilayer structure according to claim 1,
Each of the gas barrier thermoplastic resin layers is composed of EVOH (ethylene-vinyl acetate saponified product). In the multilayer structure according to claim 1 or 2,
The said olefin resin intermediate | middle layer consists of adhesive resin, The multilayer structure characterized by the above-mentioned. The multilayer structure according to any one of claims 1 to 3,
Of the olefin-based resin outer surface layers provided on both outer sides, one outermost olefin-based resin outer surface layer is made of an adhesive resin. A multilayer container formed from the multilayer structure according to any one of claims 1 to 4. The multilayer container according to claim 5,
An outer container made of heat-resistant water paper that is bonded to the outside of the multilayer container main body and does not peel off in hot water at 135 ° C. or less and does not cause appearance defects such as wet wrinkles after drying. Multi-layer container.

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