JP2023046555A - Laminated film, packaging container, packaging body and manufacturing method of laminated film - Google Patents

Abstract

To provide a laminated film for packaging provided with excellent aroma retention and capable of suppressing carbon dioxide generated from a content from filling a package interior.SOLUTION: A laminated film for packaging includes a substrate layer 3, an adhesive layer 2, and a low-adsorptive heat-seal layer 1 for suppressing adsorption and permeation of aromatic components in this order, wherein a surface 1S on an opposite side from at least the adhesive layer of the low adsorptive heat-seal layer has heat sealability, and contains 15 mass% or more and 60 mass% or less of a cyclic olefin resin, and carbon dioxide permeability of the laminated film is 7000 ml/(m2 24h atm) or more.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present disclosure relates to a laminated film, a packaging container and package using the same, and a method for producing the laminated film.

In a package filled with a content that generates carbon dioxide (carbon dioxide gas) during storage, the generated carbon dioxide fills the interior of the package, causing the package to swell. When the contents are roasted coffee beans or their pulverized granules, the amount of carbon dioxide generated is particularly large. In order to prevent such a phenomenon, the package is provided with a valve for releasing carbon dioxide (carbon dioxide gas). However, normal valves release not only carbon dioxide but also flavoring at the same time, causing the original aroma of coffee to be lost.

Against this background, a degassing valve has been proposed that allows gas to pass through selectively, leaving only carbon dioxide to escape while leaving the aromatic components (Patent Document 1). Also, in order to prevent the escape of aromatic components, films and laminates have been proposed that absorb carbon dioxide to prevent expansion (Patent Document 2).

JP-A-7-208626 JP 2020-163744 A

In the invention of Patent Document 1, since there is a step of attaching the valve, a preparation step of the valve, which is a separate part, and a step of attaching it are separately required, which complicates the manufacturing process and increases the cost. . In addition, the carbon dioxide gas absorbing film described in Patent Document 2 has a problem that it is difficult to expand the weight bag because the absorption amount of the film is saturated when the absorption amount exceeds a certain level. In addition, there is a problem that the development range is narrowed because there is no guarantee regarding the persistence of the fragrant component.

The present disclosure is an invention made in view of the above problems, and a laminated film for packaging that has excellent aroma retention and can suppress the filling of the inside of the package with carbon dioxide generated from the contents. The main purpose is to provide

In order to achieve the above object, the present disclosure is a laminated film for packaging having, in this order, a substrate layer, an adhesive layer, and a low-adsorptive heat-seal layer for suppressing adsorption and permeation of aromatic components. , At least the surface of the low-adsorptive heat seal layer opposite to the adhesive layer side has heat sealability and contains 15% by mass or more and 60% by mass or less of a cyclic olefin resin, and the laminated film Provided is a laminated film having a carbon dioxide permeability of 7000 ml/(m ² ·24 h·atm) or more.

Further, the present disclosure provides a packaging container comprising the laminated film described above.

In addition, the present disclosure provides a package including the above-described packaging container and a content that is hermetically housed in the packaging container and that generates carbon dioxide and contains an aromatic component.

In the present disclosure, it is possible to provide a laminated film that has excellent aroma retention properties and that can suppress filling of the inside of the package with carbon dioxide generated from the contents.

1 is a schematic cross-sectional view illustrating a laminated film of the present disclosure; FIG. 1 is a schematic cross-sectional view illustrating a laminated film of the present disclosure; FIG. It is a GC analysis evaluation result in an Example. 1 is a schematic perspective view illustrating a packaging container of the present disclosure; FIG.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings and the like. However, the present disclosure can be embodied in many different modes and should not be construed as limited to the description of the embodiments exemplified below. In addition, in order to clarify the description, the drawings may schematically represent the width, thickness, shape, etc. of each part compared to the embodiment, but this is only an example, and the interpretation in the present disclosure is limited. not something to do. In addition, in this specification and each figure, the same reference numerals may be given to the same elements as those described above with respect to the existing figures, and detailed description thereof may be omitted as appropriate. Also, for convenience of explanation, the terms "upper" and "lower" may be used, but the up-down direction may be reversed.

Also, in this specification, there is no particular limitation when a configuration such as a member or a region is “above (or below)” another configuration such as another member or another region. So far, this includes not only when directly above (or directly below) other structures, but also when above (or below) other structures, i.e. above (or below) other structures and between other structures. Including cases where the constituent elements of are included.

A. Laminated Film FIG. 1 is a schematic cross-sectional view illustrating a laminated film of the present disclosure. The laminated film 10 of the present disclosure shown in FIG. 1 is a laminated film for packaging, and includes a base layer 3, an adhesive layer 2, a low-adsorptive heat seal layer 1 for suppressing adsorption and permeation of aromatic components, in this order. In the present disclosure, at least the surface 1S of the low-adsorptive heat-seal layer 1 opposite to the adhesive layer 2 side has heat-sealing properties and contains 15% by mass or more and 60% by mass or less of a cyclic olefin resin. Further, the laminated film 10 is characterized by having a carbon dioxide permeability of 7000 ml/(m ² ·24 h·atm) or more. In the laminated film of the present disclosure, "at least the surface of the low-adsorptive heat-seal layer opposite to the adhesive layer side" is used when a packaging container is produced with the laminated film and the contents are hermetically accommodated. becomes the surface in contact with the

The present inventors have found that the surface opposite to the adhesive layer includes a low-adsorptive heat seal layer, which is a layer containing a specific range of cyclic olefin resin, and the carbon dioxide permeability is a specific value or more. The present inventors have found that a laminated film for packaging has excellent aroma retaining properties and can suppress filling of the inside of the package with carbon dioxide generated from the contents. Moreover, with such a laminated film, there is no need to attach a gas release bubble or the like to the packaging container, which facilitates the manufacturing process and enables cost reduction. In addition, since there is no possibility that the absorption amount of the film will be saturated when the absorption amount exceeds a certain level, unlike the carbon dioxide absorption film, it can also be used for heavy bags.

The carbon dioxide permeability of the laminated film of the present disclosure is 7000 ml/(m ² ·24 h·atm) or more. By setting the above range or more, when contents that generate carbon dioxide such as coffee beans are stored in a packaging container made using a laminated film, it is possible to suppress the generated carbon dioxide from filling the inside of the package. This is because it is possible to suppress the occurrence of problems such as damage to the packaging container due to the generated carbon dioxide. On the other hand, the upper limit of the carbon dioxide permeability is not particularly limited, but may be, for example, 50000 ml/(m ² ·24 h·atm) or less.

In the present disclosure, carbon dioxide permeability is a value obtained by the following measurement method.
[Measuring method]
The carbon dioxide permeability is measured using a "gas permeability measuring device for polymer electrolyte membrane GTR-10FC" (manufactured by GTR Tech Co., Ltd.) under the conditions of a temperature of 23 ° C. and a humidity of 60% RH, according to JIS K 7126-2. (Plastics-Film and Sheet-Gas Permeability Test Method-Part 2: Isobaric Method). The size of the sample piece is circular with a diameter of 50 mm.

1. Low-adsorptive heat-seal layer The low-adsorptive heat-seal layer in the present disclosure is a resin film containing a cyclic olefin-based resin and having heat-sealing properties. By containing a cyclic olefin-based resin, it is possible to suppress the adsorption and permeation of aromatic components. In the present disclosure, at least the surface of the low-adsorptive heat-seal layer opposite to the adhesive layer side (base material layer side) contains 15% by mass or more and 60% by mass or less of the cyclic olefin resin. By containing 15% by mass or more and 60% by mass or less of the cyclic olefin resin, it is possible to obtain excellent aroma retention and necessary seal strength.

The low-adsorptive heat-seal layer may have a single-layer structure or a multi-layer structure of two or more layers, preferably a multi-layer structure of two or more layers. In the case of a multilayer structure, the composition of each layer may be the same or different, and may include a layer that does not contain a cyclic olefin resin, and two or more layers with different contents of the cyclic olefin resin. layer may be included. In the present disclosure, a layer containing a cyclic olefin resin is referred to as a cyclic olefin resin layer.

Additionally, the low adsorption heat seal layer can optionally contain low density polyethylene. The low-density polyethylene used in the present disclosure may be a high-pressure low-density polyethylene (hereinafter sometimes referred to as LDPE) or a linear low-density polyethylene (hereinafter sometimes referred to as LLDPE). There may be.
In addition, the low-density polyethylene in the present disclosure is a concept including both the LDPE and the LLDPE.
The low-density polyethylene may be mixed with a cyclic olefin resin and contained in the cyclic olefin resin layer, or may be contained in the resin film as a polyethylene layer containing no cyclic olefin resin.

FIG. 2 is a schematic cross-sectional view illustrating a laminated film 10 having a low-adsorptive heat-seal layer 1 having a multi-layer structure. The low-adsorptive heat seal layer 1 shown in this example includes a cyclic olefin-based resin layer 11 containing a cyclic olefin-based resin and a polyethylene layer 12 . The cyclic olefin-based resin layer 11 of this example includes a low-content cyclic olefin-based resin layer 11b containing 15% by mass or more and 60% by mass or less of a cyclic olefin-based resin, and a high-content cyclic olefin-based resin layer 11a described later. and the polyethylene layer 12 has a layer 12a made of LDPE and a layer 12b made of LLDPE.

(1) Cyclic olefin-based resin layer The cyclic olefin-based resin layer in the present disclosure is a layer containing a cyclic olefin-based resin, and is a layer excellent in low permeability and low adsorption of aromatic components.
The cyclic olefin-based resin layer in the present disclosure has at least a layer (low-content cyclic olefin-based resin layer) containing 15% by mass or more and 60% by mass or less of a cyclic olefin-based resin, and the low-content cyclic olefin-based resin layer It is preferable that the resin layer is positioned so as to constitute the surface of the low-adsorptive heat seal layer opposite to the adhesive layer side (preferably, the outermost surface of the laminated film). The content of the cyclic olefin resin in the low-content cyclic olefin resin layer is preferably 50% by mass or less, more preferably 40% by mass or less. For example, if the other resin to be mixed is low-density polyethylene, the heat-sealing property can be further improved.

The amount of the cyclic olefin resin can be quantified by a crystallization elution fractionation method, which is a fractionation method that utilizes the difference in crystallinity.

The cyclic olefin-based resin layer in the present disclosure may have a single-layer structure consisting of one layer or a multilayer structure consisting of two or more layers, preferably a multilayer structure consisting of two or more layers.

The cyclic olefin-based resin layer may include a layer consisting only of a cyclic olefin-based resin, or may include a layer containing a mixture of a cyclic olefin-based resin and another type of thermoplastic resin. Another preferred type of thermoplastic resin is polyethylene. This is because low adsorption and low permeability of aromatic components and heat-sealing properties can be reliably exhibited. Among these, a layer containing a mixture of a cyclic olefin resin and low-density polyethylene is more preferable.

In the present disclosure, the cyclic olefin-based resin layer contains 80% by mass or more and 97% by mass or less of the cyclic olefin-based resin and 3% by mass or more and 20% by mass or less of the LDPE in the total resin components. It is preferable to have a certain high-content cyclic olefin-based resin layer.
Further, in all resin components, the cyclic olefin resin is 15% by mass or more and 60% by mass or less, the LDPE is 3% by mass or more and 10% by mass or less, and the LLDPE is 30% by mass. % or more and 80 mass % or less of the low content cyclic olefin resin layer.

In this case, the low-content cyclic olefin-based resin layer is preferably laminated on the surface of the low-adsorptive heat-seal layer opposite to the adhesive layer side. This is because such a layer structure can provide an excellent balance between low adsorptivity, low permeability, and heat-sealing properties.

The amounts of LDPE and LLDPE can be quantified by a crystallization elution fractionation method, which is a fractionation method utilizing the difference in crystallinity.

The cyclic olefin-based resin in the present disclosure is preferably a polynorbornene-based resin using a norbornene-based monomer as the cyclic olefin, and more preferably a copolymer of a norbornene-based monomer and an alkene monomer. A norbornene-based monomer is a compound having a bicyclo[2.2.1]hept-2-ene (norbornene) skeleton. Specifically, for example, bicyclo[2.2.1]hept-2-ene and its derivatives, tricyclo[4.3.0.1 ^2.5 ]-3-decene and its derivatives, tricyclo[4.4 .0.1 ^2.5 ]-3-undecene and its derivatives, tetracyclo[4.4.0.1 ^2.5 . 1 ^7.10 ]-3-dodecene and its derivatives, pentacyclo[6.5.1.1 ^3.6 . 0 ^2.7 . 0 ^9.13 ]-4-pentadecene and its derivatives, pentacyclo[7.4.0.1 ^2.5 . ^19.12 . 0 ^8.13 ]-3-pentadecene and its derivatives, pentacyclo[6.5.1.1 ^3.6 . 0 ^2.7 . 0 ^9.13 ]-4,10-pentadecadiene and its derivatives, pentacyclo[8.4.0.1 ^2.5 . ^19.12 . 0 ^8.13 ]-3-hexadecene and derivatives thereof, and the like, but are not limited thereto. These norbornene-based monomers may have polar groups such as ester groups, carboxyl groups, and carboxylic anhydride groups as substituents. These compounds may be used alone or in combination of two or more.

Among these, bicyclo[2.2.1]hept-2-ene (norbornene) is preferable as the norbornene-based monomer.

As alkene monomers, α-olefin monomers are preferred, and specific examples include ethylene, propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene. etc. These compounds may be used alone or in combination of two or more. Among these, ethylene is preferable as the alkene monomer.

The glass transition temperature (Tg) of the cyclic olefin resin is not particularly limited, but is preferably 60° C. or higher and 170° C. or lower because it is easy to handle as a raw material resin for packaging materials.

(2) Polyethylene layer The low-adsorptive heat-seal layer of the present invention can contain a polyethylene layer, if necessary. A polyethylene layer is a layer which does not contain cyclic olefin system resin but contains polyethylene. Here, polyethylene is preferably low-density polyethylene, and examples of low-density polyethylene include LDPE and LLDPE described above.
The polyethylene layer may have two or more layers having the same or different compositions. For example, it is preferable that a layer made of LDPE and a layer made of LLDPE are laminated.

The polyethylene layer preferably constitutes the surface of the low-adsorptive heat-seal layer on the side of the adhesive layer, and the layer made of LDPE constitutes the surface of the low-adsorptive heat-seal layer on the side of the adhesive layer. is more preferred. The lamination strength of the laminated film can be improved by using the surface of the polyethylene layer as an adhesive surface when producing the laminated film.

(3) Others In addition, the low-adsorptive heat-sealing layer may have anti-blocking properties, workability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, slip properties, and releasability as needed. Anti-blocking agents, lubricants, cross-linking agents, antioxidants, UV absorbers, light stabilizers, fillers, reinforcing agents, etc. , Antistatic agents, pigments, and other plastic compounding agents and additives can be added. .

Among these, anti-blocking agents, lubricants, etc., when the low-adsorptive heat-seal layer has a multilayer structure, the outermost layer of the low-adsorptive heat-seal layer (in FIG. 2, low-adsorptive heat-seal layer 1 can be efficiently added by adding only to the layer on the surface 1S) opposite to the surface on the adhesive layer 2 side.

Furthermore, the surface of the low-adsorptive heat-seal layer or each layer constituting the low-adsorptive heat-seal layer is subjected to corona discharge treatment, ozone treatment, oxygen gas or nitrogen treatment in advance before lamination in order to improve adhesion. A physical treatment such as a low-temperature plasma treatment using a gas or the like, a glow discharge treatment, or a chemical treatment such as an oxidation treatment using a chemical agent can also be performed.

The total thickness of the low-adsorptive heat seal layer is preferably 20 µm or more and 150 µm or less. If the thickness is less than the above range, the fragrance retention may become insufficient. easy.

In the present disclosure, the thickness of the cyclic olefin resin-containing layer is preferably 20% or more and 50% or less of the total thickness of the low-adsorptive heat seal layer. If it is thinner than the above range, the aroma retention may become insufficient. It tends to be difficult to pick.

(4) Method for producing low-adsorptive heat-seal layer In the present disclosure, the low-adsorptive heat-seal layer is made of a low-adsorptive heat-seal film.
The low-adsorptive heat-seal film and the method of forming and laminating each layer in the low-adsorptive heat-seal film are not particularly limited, and known or commonly used film-forming methods and lamination methods can be applied.

Each layer constituting the low-adsorptive heat-seal film may be extruded or co-extruded onto another layer, optionally through an adhesive layer, and laminated by an extrusion coating method, or multiple layers may be extruded or co-extruded for inflation. It can also be formed into a film by a method or by a casting method.

Alternatively, pre-formed films of each layer may be laminated via an adhesive layer by an adhesive extrusion coating method, dry lamination method, non-solvent lamination method, or the like.

In the case of lamination by an extrusion coating method, first, the resin or resin composition forming each layer is heated and melted, expanded and stretched in the necessary width direction with a T-die, and extruded in a curtain shape, and the melt is is allowed to flow down onto the surface to be laminated, and sandwiched between the rubber roll and the cooled metal roll, formation of each layer, adhesion to the surface to be laminated, and lamination can be performed simultaneously.

The melt flow rate (MFR) of the resin or resin composition of each layer when laminated by extrusion coating is preferably 0.2 to 50 g/10 minutes, more preferably 0.5 to 30 g/10 minutes. preferable. If the MFR is lower or higher than the above range, the processability tends to be poor. In addition, MFR is the value measured by the method based on JISK7210.

When using the inflation method, the melt flow rate (MFR) of the resin or resin composition of each layer is preferably 0.2 to 10 g/10 minutes, more preferably 0.2 to 9.5 g/10 minutes. . If the MFR is lower or higher than the above range, the processability tends to be poor.

2. Base layer The base layer of the laminated film of the present disclosure is not particularly limited as long as the carbon dioxide permeability of the laminated film can be within the above range, and any film depending on the application of the laminated film. Or you can use a sheet.
As the base material layer, for example, a nylon film, a polyethylene film, a polypropylene film, or the like can be suitably used, and a paper material or the like can also be used. These may be used singly or in combination. The substrate layer may be a stretched film or an unstretched film, and may be a uniaxially or biaxially stretched film for the purpose of improving strength.

Further, an adhesive layer is provided on the surface of the base material layer or between each layer constituting the base material layer in order to improve adhesion, or the surface of each layer is optionally subjected to a desired surface treatment in advance. Layers can be provided.
For example, pretreatment such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, oxidation treatment using chemicals, etc. can be optionally applied to the corona treatment layer and ozone treatment. Layers, plasma-treated layers, oxidation-treated layers, etc. can be formed and provided.
Alternatively, various coating agent layers such as a primer coating agent layer, an undercoat agent layer, an anchor coating agent layer, an adhesive layer, and a vapor deposition anchor coating agent layer can be arbitrarily formed on the surface to serve as the surface treatment layer. .

When the base material layer includes a layer made of paper material, it is preferable to further have a protective layer on the surface of the paper material opposite to the low-adsorptive sealant layer. The protective layer improves the water resistance of the substrate layer when the content is a wet content, and preferably contains a polyethylene-based resin.

3. Adhesive Layers In the present disclosure, adhesive layers may provide adhesion between layers. The adhesive layer can be formed using generally known dry lamination adhesives, EC (extrusion coat) adhesives, non-solvent lamination adhesives, arbitrary anchor coat agents, and the like.
The adhesive may be of a thermosetting type, an ultraviolet curable type, an electron beam curable type, or the like, and may be in any form such as an aqueous type, a solution type, an emulsion type, or a dispersion type. It may be in any form such as shape, powder, solid, etc. Further, the adhesion mechanism may be in any form such as chemical reaction type, solvent volatilization type, heat fusion type, heat pressure type, or the like.

4. Other Layers The laminated films of the present disclosure may include printed layers. There is no particular limitation on the printed content of the printed layer. For example, there are letters, monochromatic solid patterns, bright and dark color patterns, uneven patterns, and those exhibiting diffraction gloss due to unevenness. Moreover, it may be formed by printing with a printing machine, may be drawn with a writing tool, or may be a laminate of films or sheets having patterns and letters.

The thickness of the printed layer can be appropriately determined by those skilled in the art according to the printed content and the application of the laminated film, but it is preferably 5 to 500 μm, more preferably 10 to 300 μm. Various surface treatments may be applied to the surface of the printed layer, if necessary, in order to improve adhesion.

The laminated film of the present disclosure preferably does not have a barrier layer. This is because it makes it difficult for carbon dioxide to permeate. In the present disclosure, the barrier layer includes one or more selected from the group consisting of a metal foil, a metal vapor deposition film, and a metal oxide vapor deposition film.

5. Uses The laminated film of the present disclosure is used in a container containing a liquid or solid that generates carbon dioxide and contains an aromatic component, specifically, roasted coffee beans or a granulated product thereof. is preferred.

By using it as a container for roasted coffee beans or its powdered granules, carbon dioxide generated from the roasted coffee beans or its powdered granules can be discharged outside the container, and a special internal pressure can be adjusted. It is possible to prevent the container from being damaged due to the filling of carbon dioxide during long-term storage without using a molded product for holding the roasted coffee beans or the granulated coffee beans. It is possible to prevent missing.

Specifically, the laminated film of the present disclosure has a function of preventing permeation of the aromatic components of roasted coffee beans or granulated products thereof.
In the present disclosure, aldehyde/ketone-based compounds, cyclic ether furan-based compounds, hydrocarbon-based compounds, sulfur-based compounds, ester-based compounds, and the like are mentioned as the above-mentioned aromatic components. Specifically, acetaldehyde, acetone, 2-butanone, 2-methylbutanal, 3-methylbutanal, aldehyde-ketone compounds such as diacetyl, furan, 2-methylfuran, 3-methylfuran, 2,5- Examples include cyclic ether furan compounds such as dimethylfuran, hydrocarbon compounds such as 2-pentene and isobutene, sulfur compounds such as carbonyl sulfide, and ester compounds such as methyl acetate.

B. In the method for producing a laminated film in the present disclosure, at least one surface has heat sealability and contains 15% by mass or more and 60% by mass or less of a cyclic olefin resin, for suppressing adsorption and permeation of aromatic components. a step of preparing a low-adsorptive heat-sealable film; a step of applying an adhesive onto a substrate; A method for producing a laminated film for packaging, comprising a step of bonding the laminated film to the base material via the adhesive so as to form a film. With such a laminated film manufacturing method, it is possible to obtain a laminated film for packaging that has excellent aroma retention and can suppress the filling of the inside of the package with carbon dioxide generated from the contents. can be done.

1. Low-adsorptive heat-seal film preparation process Low-adsorptive heat-seal film is the low-adsorptive heat-seal film described in detail in the above "A. Laminated film 1. Low-adsorptive heat-seal layer", so the explanation here is as follows. omitted. Also, the low-adsorptive heat-seal film is preferably prepared by being manufactured by an extrusion coating method or an inflation method.

2. Adhesive application step The base material and the adhesive are the same as those described in "A. Laminated film 2. Base layer" and "A. Laminated film 3. Adhesive layer", so descriptions thereof will be omitted here.

3. Bonding Step In the bonding step, the low-adsorptive heat-sealable film is bonded to the substrate via an adhesive such that the surface having heat-sealability is on the side opposite to the adhesive. As a result, a laminated film for packaging is obtained which has, in this order, a substrate layer, an adhesive layer, and a low-adsorptive heat-seal layer for suppressing the adsorption and permeation of aromatic components.

C. Packaging Container The present disclosure provides a packaging container comprising the laminated film described above. A packaging container according to the present disclosure is a packaging container produced using the above-described laminated film such that the low-adsorptive heat-seal layer is in contact with the contents. With such a packaging container, it is possible to prevent the interior from being filled with carbon dioxide generated from the contents when the contents that generate carbon dioxide are hermetically accommodated while having excellent aroma retention properties. can be suppressed. FIG. 4 shows a schematic perspective view of the packaging container of the present disclosure. A packaging container 100 shown in FIG. 4 includes a laminated film 10 and is capable of containing contents therein.

1. Laminated Film The laminated film used for the packaging container of the present disclosure has been described in the section "A. Laminated Film" above, and thus description thereof is omitted here.

2. Packaging Container The shape of the packaging container of the present disclosure is not particularly limited, and may be bag-shaped, box-shaped, tube-shaped, or the like. The packaging container is preferably sealable. As the bag-like packaging container, for example, the above-described laminated film is used and folded in two, or two laminated films are prepared, and the low-adsorptive sealant layers are placed on top of each other so that they face each other. Further, the peripheral edge is subjected to, for example, a side seal type, a two-side seal type, a three-side seal type, a four-side seal type, an envelope pasted seal type, a palm pasted seal type (pillow seal type), a pleated seal type, and a flat bottom seal. There are various types of packaging bags made by heat-sealing in a heat-sealed form such as a mold, a square bottom seal type, and a gusset type. As for the shape of the bag, it is preferable that the bag is sealed in the form of a pouch bag.

In the above, the heat sealing can be carried out by known methods such as bar sealing, rotary roll sealing, belt sealing, impulse sealing, high frequency sealing and ultrasonic sealing.

As a box-shaped packaging container, for example, a laminated film of the present disclosure having a paper material as a base material layer is used, and a low-adsorptive sealant layer is made into a box to serve as a content layer.

The packaging container of the present disclosure may comprise a molded product. For example, it can be provided with a spout for taking out the contents (especially roasted coffee beans or granules thereof). The packaging container of the present disclosure may also comprise resealing means. For example, zipper tape can be used as the resealing means. As shown in FIG. 4, the zipper tape 101 has, for example, a male member X and a female member Y. It is constructed by attaching a male member X and attaching a female member Y on the opposite side. After opening the packaging container, the packaging container can be resealed by fitting the male and female members together.

On the other hand, the packaging container of the present disclosure does not require a gas release valve because it uses a laminated film that is highly permeable to carbon dioxide generated from the contents (especially roasted coffee beans or granulated products thereof). Therefore, it is possible to prevent the aroma and flavor of the contents (especially roasted coffee beans or granules thereof) from escaping to the outside of the packaging container through the gas release valve. Gas release valves include, for example, seal-type outer valves and button-type inner valves. These gas release valves function as valves when, for example, the pressure inside the package becomes higher than the outside of the package due to carbon dioxide generated from the contents, and the carbon dioxide (carbon dioxide gas) filled inside the package ) is discharged to the outside, and the air pressure inside the packaging bag is adjusted to be the same as the outside.

D. Package The present disclosure provides a package having the above-described packaging container and a content that is hermetically housed in the packaging container and that generates carbon dioxide and contains an aroma component. Such a package is excellent in maintaining the aroma of the contents, and can suppress filling of the interior with carbon dioxide generated from the contents.

1. Packaging Container The packaging container in the present disclosure has been described in the section “C. Packaging Container” above, so description thereof will be omitted here. The packaging container in the package is in a sealed state.

2. Contents The contents to be filled in the packaging container are liquids, solids, etc. that generate carbon dioxide and contain aromatic components, and specifically include roasted coffee beans or granulated products thereof. be done.

Examples and comparative examples are shown below to describe the present disclosure in more detail.

[Preparation of low-adsorptive heat seal film 1]
(1) As the resin composition constituting the high-content cyclic olefin-based resin layer, COC (TOPAS (registered trademark) 8007F-600 (manufactured by Polyplastics Co., Ltd.), the norbornene-derived repeating unit content of 65% by mass, Glass transition temperature 78° C.) 97% by mass and LDPE (Suntech M6545 manufactured by Asahi Kasei Chemicals Corporation, MFR 45.0 g/10 minutes, density 0.915 g/cm ³ ) 3% by mass are sufficiently kneaded to form a resin composition. prepared the product.
(2) As the resin composition constituting the low content cyclic olefin resin layer, COC (TOPAS (registered trademark) 8007F-600 (manufactured by Polyplastics Co., Ltd.)) 20% by mass, LLDPE (Ube Maruzen Polyethylene Co., Ltd. ) manufactured by Yumerit (registered trademark) 0520F, MFR 2 g / 10 minutes, density 0.904 g / cm ³ ) 45% by mass, LDPE (Suntec M6525) 5% by mass, and anti-blocking agent masterbatch (manufactured by Sumitomo Chemical Co., Ltd., EMB-21, MFR 4 g/10 min, synthetic zeolite content) were sufficiently kneaded to prepare a resin composition.
(3) LDPE (Novatec (registered trademark) LC522, MFR 4.0 g/10 min, density 0.923 g/cm ³ , manufactured by Nippon Polyethylene Co., Ltd.) was prepared as a resin constituting the outer layer and the first polyethylene layer. Furthermore, LLDPE (Prime Polymer Ultozex (registered trademark) 1520L, MFR 2.3 g/10 min, density 0.914 g/cm ³ ) was prepared as a resin constituting the second polyethylene layer.
(4) Using the resins and resin compositions prepared in (1) to (3) above, a 5-layer co-extrusion film formation method using an inflation method is performed to form an outer layer of 7.5 μm/first polyethylene layer of 7.5 μm. / Second polyethylene layer 10 μm / High content cyclic olefin resin layer 7.5 μm / Low content cyclic olefin resin layer 7.5 μm Manufacture low adsorptive sealant film 1 (thickness 40 μm) bottom. In the specification of the present application, "/" indicates that the left and right layers are laminated and integrated. The cyclic olefin resin content ratio in the low-adsorptive heat seal film was 23.2%. In addition, when a laminated film is formed, the cyclic olefin resin content ratio of the low content cyclic olefin resin layer that constitutes the surface opposite to the adhesive layer side of the low adsorptive sealant film (low adsorptive heat seal layer) is , 20 mass %.

[Preparation of low-adsorptive heat seal film 2]
(1) As a resin composition constituting a high content cyclic olefin resin layer, COC (TOPAS (registered trademark) 8007F-600 manufactured by Polyplastics Co., Ltd., content of norbornene-derived repeating units 65% by mass, glass transition Temperature 78° C.) 97% by mass and LDPE (Suntech M6545 manufactured by Asahi Kasei Chemicals Corporation, MFR 45.0 g/10 min, density 0.915 g/cm ³ ) 3% by mass are sufficiently kneaded to form a resin composition. prepared.
(2) As the resin composition constituting the low content cyclic olefin resin layer, COC (TOPAS (R) 8007F-600) 20% by mass, LLDPE (Ube Maruzen Polyethylene Co., Ltd. Yumerit (R) 0520F, MFR 2 g / 10 minutes, density 0.904 g/cm ³ ) 45% by mass, LDPE (Suntec M6525) 5% by mass, and anti-blocking agent master batch (manufactured by Sumitomo Chemical Co., Ltd., EMB-21, MFR 4 g/10 minutes, synthetic zeolite content) 30% by mass was sufficiently kneaded to prepare a resin composition.
(3) LDPE (Novatec (registered trademark) LC522 manufactured by Nippon Polyethylene Co., Ltd., MFR 4.0 g/10 min, density 0.923 g/cm ³ ) was prepared as a resin constituting the polyethylene layer of the outer layer.
(4) Using the resin and resin composition prepared in (1) to (3) above, a three-layer co-extrusion film formation method using an inflation method is performed to form an outer layer of 5 μm/high content cyclic olefin resin layer of 20 μm/ A low-adsorptive sealant film 2 (thickness: 40 μm) having a layer configuration of a low-content cyclic olefin-based resin layer of 15 μm was produced. The cyclic olefin resin content ratio in the low-adsorptive heat seal film was 57.5%. In addition, when a laminated film is formed, the cyclic olefin resin content ratio of the low content cyclic olefin resin layer that constitutes the surface opposite to the adhesive layer side of the low adsorptive sealant film (low adsorptive heat seal layer) is , 20 mass %.

[Preparation of laminated film]
(Example 1, Example 2)
A polyester urethane adhesive (RU-004/H-1 (blending ratio: 7.5/1) manufactured by ROCK PAINT) was applied to each of the following substrates in an amount of 3.5 to 4 g/m ² and dried. After that, the low-adsorptive sealant film 1, which is a sealant layer, is dry-laminated so that the outer layer is on the adhesive layer side, and left to stand at 40 ° C. for 72 hours to form a paper/adhesive layer/low-adsorbent heat seal film 1. Laminated film 1 having a structure (Example 1) and laminated film 2 having a structure of PEF/adhesive layer/low-adsorptive heat seal film 1 (Example 2) were obtained.
Paper: Nippon Paper Industries CUP-AC (F) 255 g/m ²
PEF (low-density polyethylene film): Dai Nippon Printing SKS 40 μm

(Example 3)
^Adhesive ( Rock Paint Co., Ltd., RU-004/H-1 (blending ratio 7.5/1)) is applied at a coating amount of 3.5 to 4 g / m ² , and after drying, a low-adsorptive sealant film 1 that is a sealant layer was dry-laminated so that the outer layer was on the adhesive layer side and allowed to stand at 40° C. for 72 hours to obtain a laminated film 3 having a structure of paper/PE/adhesive layer/low adsorptive heat seal film 1.

(Comparative example 1)
Adhesive (RU-004/H-1 (mixture ratio 7.5/1) manufactured by ROCK PAINT) was applied at 3.5 to 4 g/m ² on the corona-treated surface of the base PET film (Toyobo E5100 12 μm). After drying, low-adsorptive sealant film 1, which is a sealant layer, was dry-laminated so that the outer layer faced the adhesive layer side, and allowed to stand at 40°C for 72 hours. A laminated film 4 having a configuration of PET/adhesive layer/low-adsorptive heat seal film 1 was obtained.

[Measurement of carbon dioxide permeability]
Carbon dioxide permeability was measured for the obtained laminated film. The measurement was performed based on JIS K 7126-2 (isobaric formula). As a measuring device, “Polymer electrolyte membrane gas permeability measuring device GTR-10FC” (manufactured by GTR Tech Co., Ltd.) was used. The size of the sample piece was disc-shaped with a diameter of 50 mm.
The carbon dioxide permeabilities of laminated film 1, laminated film 2, and laminated film 3 are, respectively,
12,000 ml/(m ² ·24 h·atm), 10,200 ml/(m ² ·24 h·atm), 8,500 ml/(m ² ·24 h·atm). The carbon dioxide permeability of the laminated film 4 was 2000 ml/(m ² ·24 h·atm).

[evaluation]
The laminated film produced above and the low-adsorptive heat seal film used for production of the laminated film were evaluated as follows.

·Evaluation of Carbon Dioxide Permeability The carbon dioxide permeability of the laminated films of Example 1, Example 3 and Comparative Example 1 produced above was evaluated as follows. Using the laminated film, a pouch having a size of half A4 was produced, 20 g of content was put therein, and the pouch was sealed. A double bag was prepared using a non-adsorbing pouch (GL Sciences SMART BAG) which was one size larger than the pouch as an outer bag. Each was stored at normal temperature and 37° C. dry for 1 week. After storage, the air between the inner bag and the outer bag containing the contents was sucked with a syringe, and the carbon dioxide concentration in the syringe was measured with a Dansensor "CheckPoint II" manufactured by MOCON. The carbon dioxide permeability of the low-adsorptive heat seal film alone (COC film) and the polyethylene film alone (PE film) were similarly evaluated. Table 1 shows the results.

・Fragrance retention evaluation (GC analysis, sensory evaluation)
The aroma retention property of the laminated film produced above was subjected to GC analysis evaluation and sensory evaluation as follows.
(1) GC analysis evaluation Using the low-adsorptive heat seal film alone (COC film) produced above, the polyethylene film alone (PE film), and a perforated aluminum bag as a reference, a pouch half the size of A4 was made. It was prepared, filled with 20 g of content, and sealed. 20 g of roasted coffee beans are put in, and a double pouch with a non-adsorbing pouch (GL Sciences SMART BAG), which is one size larger, is stored as an outer bag at 37 ° C. for one and a half months. *) were compared. An appropriate amount of gas was sucked from the space between the inner bag and the outer bag with a syringe, and the gas components were analyzed. For the analysis, a sniffing GC device "7890A GC System manufactured by Agilent" was used. The analysis results are shown in FIGS. 3(a) to 3(c).
*Blank product: The same amount of contents (roasted coffee beans) was put directly into a non-adsorbing pouch, the gas inside the pouch was directly sucked, and the same amount was analyzed.

(2) Sensory evaluation As sensory evaluation, comparison was made as low, slightly low, and equivalent. The evaluation method and evaluation criteria are shown below.
[Evaluation method]
Using the laminated films of Examples 1, 3 and Comparative Example 1 produced above, double pouches were produced in the same manner as in "(1) GC analysis evaluation" above, and leakage from the pouch (inner bag) In order to confirm the smell, the outer bag of the double pouch was opened, and each specification was smelled through the nose once for comparison. Five test subjects performed the above action twice using the same pouch, and were scored in comparison with blanks according to the following evaluation criteria to calculate a total score and rank them. Table 2 shows the results. A specification with a low score (in other words, a small amount of leaked odor) is able to contain the odor inside. That is, it means that the flavor is retained.
Evaluation criteria 1: No smell 2: Slight smell 3: Smell 4: Strong smell.

From Table 1, it was confirmed that the laminated film of the present disclosure has good carbon dioxide permeability. From FIG. 3, it was confirmed that when the low-adsorptive heat seal film was used, the strength and area of the aromatic components tended to be smaller than those of the blank, that is, the gas permeation of the aromatic components could be suppressed. Moreover, it was confirmed that the strength and area of each component tended to be smaller than those of perforated aluminum bags and PE bags. Further, from the results in Table 2, it was confirmed that there is a correlation between the analysis results of odor GC (FIG. 3) and the sensory evaluation results.

Note that the present disclosure is not limited to the above embodiments. The above embodiment is an example, and any device that has substantially the same configuration as the technical idea described in the claims of the present disclosure and achieves the same effect is the present invention. It is included in the technical scope of the disclosure.

DESCRIPTION OF SYMBOLS 1... Low adsorption heat seal layer 2... Adhesive layer 3... Base material layer 10... Laminated film

Claims (11)

A laminated film for packaging comprising, in this order, a substrate layer, an adhesive layer, and a low-adsorptive heat-seal layer for suppressing the adsorption and permeation of aromatic components,
At least the surface of the low-adsorptive heat-sealing layer opposite to the adhesive layer side has heat-sealing properties and contains 15% by mass or more and 60% by mass or less of a cyclic olefin-based resin,
The laminated film has a carbon dioxide permeability of 7000 ml/(m ² ·24 h·atm) or more. 2. The laminated film according to claim 1, wherein at least the surface of said low-adsorptive heat-seal layer opposite to said adhesive layer contains a mixture of said cyclic olefin-based resin and low-density polyethylene. The low-adsorptive heat seal layer has a polyethylene layer and a cyclic olefin-based resin layer containing the cyclic olefin-based resin in this order from the adhesive layer side,
The laminated film according to claim 1 or 2, wherein the polyethylene layer does not contain the cyclic olefin resin but contains low-density polyethylene. The polyethylene layer has a layer having high-pressure low-density polyethylene and a layer having linear low-density polyethylene,
4. The laminated film according to claim 3, wherein the surface of the low-adsorptive heat-seal layer on the adhesive layer side is a layer containing the high-pressure low-density polyethylene. The cyclic olefin resin layer is
A high-content cyclic olefin resin in which the cyclic olefin resin is 80% by mass or more and 97% by mass or less and the high-pressure low-density polyethylene is 3% by mass or more and 20% by mass or less in all resin components. layer and
In all resin components, the cyclic olefin resin is 15% by mass or more and 60% by mass or less, and the high pressure low-density polyethylene is 3% by mass or more and 10% by mass or less, and a linear low density a low-content cyclic olefin-based resin layer in which polyethylene is 30% by mass or more and 80% by mass or less,
5. The laminated film according to claim 3, wherein the low-content cyclic olefin-based resin layer is laminated on the surface of the low-adsorptive heat seal layer opposite to the adhesive layer side. The laminated film according to any one of claims 1 to 5, wherein the base material layer has a layer made of paper material. 6. The laminated film according to any one of claims 1 to 5, wherein the base layer has a layer made of nylon film, polyethylene film or polypropylene film. A packaging container comprising the laminated film according to any one of claims 1 to 7. 9. A package comprising: the packaging container according to claim 8; and a content that is hermetically housed in the packaging container and that generates carbon dioxide and contains an aromatic component. 10. The package according to claim 9, wherein the contents are roasted coffee beans or a granulated product thereof. A low-adsorptive heat-sealable film for suppressing adsorption and permeation of aromatic components is prepared, wherein at least one surface has heat-sealing properties and contains 15% by mass or more and 60% by mass or less of a cyclic olefin resin. process and
applying an adhesive onto a substrate;
A step of bonding the low-adsorptive heat seal film to the base material via the adhesive so that the surface having the heat seal property is on the opposite side to the adhesive side. A method for producing a laminated film.

Images