JP2022033714A - Composite film, lid material, container with lid containing content, packaging bag, and packaging bag containing content - Google Patents

Abstract

To provide a composite film in which, when a package resealable by heat sealing is formed and then the package is opened, a resealing surface on a container body side is not be an adhesive resin layer, and to provide a lid material formed by the composite film, a container with a lid containing contents, a packaging bag, and a packaging bag containing contents.SOLUTION: By constituting a composite film for forming a package resealable by heat sealing so that an adhesive layer and an aluminum layer are adjacent to each other, when opening, interlayer separation is caused between the adhesive layer and the aluminum layer, so that an adhesive resin layer does not left on a container body side.SELECTED DRAWING: Figure 1

Description

The present invention relates to a composite film, a lid material, a container with a lid containing contents, a packaging bag, and a packaging bag containing contents.

Conventionally, various packages having a resealing function have been used as packaging means for foods and pharmaceuticals that cannot be consumed at one time. As such a package, sealing using a multilayer film has been proposed, which can impart a resealing function to the package itself without attaching an accessory such as a zipper.

As the multilayer film capable of resealing, for example, a surface resin layer (A) containing a thermoplastic resin (a) as a main component and a styrene-based thermoplastic elastomer (b) having specific physical properties are used as main components. A laminate in which an adhesive resin layer (B) and a heat-sealed resin layer (C) containing an olefin resin (c) as a main component are laminated in the order of (A) / (B) / (C) is disclosed. (See Patent Document 1).

The package in which the multilayer film described in Patent Document 1 is heat-sealed in a container body or the like and sealed can be opened and resealed without causing any problem.

Japanese Unexamined Patent Publication No. 2007-125820

However, in the package in which the multilayer film described in Patent Document 1 is heat-sealed and sealed, the surface resin layer (A) and the adhesive resin layer (B) are delaminated at the time of opening, and the heat of the container body or the like is generated. The peeled surface remaining on the sealed portion was the adhesive resin layer (B).

Therefore, for example, when it is applied as a lid material for a container such as a cup soup to be eaten with a mouth attached to the container, the adhesive resin layer (B) comes into contact with the lips, which may cause discomfort in the mouthfeel. rice field.

Further, in the case of a package having a large number of resealings, the resealing strength tends to decrease as the number of resealings increases.

The present invention has been made in view of the above background, and heat-sealed to form a resealable package, and when the package is opened, the resealed surface on the container body side becomes an adhesive resin layer. It is an object of the present invention to provide a composite film, a lid material formed from the composite film, a container with a lid containing contents, a packaging bag, and a packaging bag containing contents.

The present inventors have conducted diligent studies to solve the above problems. Then, if the composite film for heat-sealing to form a resealable package is configured so that the adhesive layer and the aluminum layer are adjacent to each other, the adhesive layer and the aluminum layer are separated from each other at the time of opening. It was found that delamination occurred in the container and no adhesive layer remained on the container body side, and the present invention was completed. That is, the present invention is as follows.

<< Aspect 1 >>
The base material layer, the adhesive layer, the aluminum layer, and the heat seal layer are included in this order.
When the adhesive layer and the aluminum layer are adjacent to each other and the heat-sealed layers are heat-sealed and peeled off from each other, or when the heat-sealed layer and another material are heat-sealed and peeled off. At the edge of the heat-sealed portion, the aluminum layer and the heat-sealed layer are broken, and at the heat-sealed portion, delamination occurs between the adhesive layer and the aluminum layer.
Composite film.
<< Aspect 2 >>
The composite film according to aspect 1, wherein the adhesive layer contains a thermoplastic elastomer.
<< Aspect 3 >>
The composite film according to aspect 2, wherein the thermoplastic elastomer is a styrene-based thermoplastic elastomer.
<< Aspect 4 >>
The composite film according to aspect 2 or 3, wherein the thermoplastic elastomer is a styrene-butadiene-butylene-styrene copolymer.
<< Aspect 5 >>
The composite film according to any one of aspects 2 to 4, further comprising a polyterpene and / or a rosin ester.
<< Aspect 6 >>
The composite film according to aspect 1, wherein the adhesive layer contains an amorphous polyester.
<< Aspect 7 >>
The composite film of embodiment 6, further comprising a polyterpene and / or a rosin ester.
<< Aspect 8 >>
The composite film according to any one of aspects 1 to 7, wherein the thickness of the adhesive layer is 5 μm or less.
<< Aspect 9 >>
The composite film according to any one of aspects 1 to 8, wherein the heat seal layer contains a polyolefin resin and has a thickness of 1 to 7 μm.
<< Aspect 10 >>
The composite film according to any one of aspects 1 to 9, wherein the heat seal layer is a polyethylene resin layer having a density of 0.920 to 0.958 g / cm ³ .
<< Aspect 11 >>
The composite film according to aspect 10, wherein the polyethylene resin layer contains high-density polyethylene and low-density polyethylene.
<< Aspect 12 >>
The composite film according to aspect 11, wherein the content of the high-density polyethylene is 50 to 90% by mass with respect to the total mass of the heat-sealed layer.
<< Aspect 13 >>
A lid material formed from the composite film according to any one of aspects 1 to 12.
<< Aspect 14 >>
The lid material according to aspect 13, which is for resealing.
<< Aspect 15 >>
The lid material according to aspect 13 or 14, wherein the adhesive layer and the aluminum layer are delaminated at the time of opening, and the adhesive layer is exposed in a resealable state with the aluminum layer.
<< Aspect 16 >>
The lid material according to any one of aspects 13 to 15, which does not have a half cut on the heat seal layer side.
<< Aspect 17 >>
The container body having a storage part and a flange part,
The contents contained in the container body and
A lid material formed from the composite film according to any one of aspects 1 to 12 is provided.
The heat seal layer is heat sealed to the flange portion to form a resealable joint.
A container with a lid containing the contents.
<< Aspect 18 >>
The container with a lid containing contents according to aspect 17, wherein at the time of opening, the adhesive layer and the aluminum layer at the joint portion are delaminated and the aluminum layer is exposed to the flange portion in a resealable state.
<< Aspect 19 >>
The container body is a paper cup and
The container with a lid containing the contents according to aspect 17 or 18, wherein the flange portion has a coating made of a polyethylene resin.
<< Aspect 20 >>
The lid material according to any one of aspects 13 to 16, or embodiments 17 to 19, wherein the base material layer and the adhesive layer are transparent so that the aluminum layer can be visually recognized from the base material layer side. A container with a lid containing the contents according to any one of the above.
<< Aspect 21 >>
A packaging bag in which the heat-sealing layer of the composite film according to any one of aspects 1 to 12 is heat-sealed at least in part.
<< Aspect 22 >>
The packaging bag according to aspect 21, wherein the adhesive layer and the aluminum layer are delaminated at the time of opening, and the adhesive layer is exposed in a resealable state with the aluminum layer.
<< Aspect 23 >>
The packaging bag according to aspect 21 or 22, which does not have a half cut on the heat seal layer side.
<< Aspect 24 >>
The packaging bag according to any one of aspects 21 to 23, the packaging bag containing the contents having the contents contained in the packaging bag.
<< Aspect 25 >>
The packaging bag according to any one of aspects 21 to 23, or embodiment 24, wherein the base material layer and the adhesive layer are transparent so that the aluminum layer can be visually recognized from the base material layer side. Packaging bag with the contents of.

(When the heat-sealing layer of the composite film of the present invention is heat-sealed on the container body or the like to form a resealable package)
According to the composite film of the present invention, the heat-sealed layer is heat-sealed on the container body or the like to form a resealable package, and when the package is opened, the portion heat-sealed on the container body or the like is formed. At the edge, the aluminum layer and the heat seal layer are broken, and at the portion heat-sealed on the container body or the like, delamination occurs between the adhesive layer and the aluminum layer.

As a result, it is possible to prevent the adhesive layer from remaining on the side of the container body or the like. For example, when the composite film of the present invention is applied as a lid material for a container such as a cup soup to be eaten with a mouth attached to the container. In addition, it is possible to prevent the adhesive layer from coming into contact with the lips and avoid a feeling of discomfort in the mouthfeel or the like.

Further, in the package formed by heat-sealing the heat-sealing layer of the composite film of the present invention to the container body or the like, the aluminum layer and the heat-sealing layer are formed at the outer and inner edges of the heat-sealed joint. Since it is broken and opened, it is not necessary to provide a notch (half cut) formed at a depth less than the thickness of the composite film from the surface of the composite film, particularly the surface on the heat seal layer side.

Therefore, it is not necessary to provide a half cut along the area where the heat seal is intended to be performed with the container, for example, the area where the container body is heat-sealed with the flange portion, and the alignment operation during the heat seal is not required. Therefore, it can contribute to productivity.

Furthermore, when a resealable package is produced using the composite film of the present invention, it is possible to suppress a decrease in resealing strength even when the number of resealings increases.

Further, when the outer layer is a transparent layer rather than the aluminum layer of the composite film of the present invention, it can be confirmed from the outside of the package that the aluminum layer is broken when the package is opened. Therefore, it is possible to visually recognize whether the package is in the unopened state or in the opened and resealed state from the outside of the package. This can also help prevent tampering in the store.

(When heat-sealing the heat-sealing layers of the composite film of the present invention with each other or heat-sealing the heat-sealing layer of the composite film of the present invention with another material such as a film to form a resealable package)
According to the composite film of the present invention, a package such as a packaging bag that can be resealed by heat-sealing the heat-sealing layers of the composite film with each other or heat-sealing the heat-sealing layer with another material such as a film can be obtained. When the package was formed and the package was opened, the aluminum layer and the heat-sealed layer were broken at the edge of the heat-sealed portion (joint portion), and the adhesive layer and the aluminum layer were formed at the heat-sealed portion. Delamination occurs between them.

As a result, in the package formed by using the composite film of the present invention, the aluminum layer and the heat seal layer are broken and opened at the outer edge and the inner edge of the joint formed by the heat seal. It is not necessary to provide a notch (half cut) formed at a depth less than the thickness of the composite film from the surface of the composite film, particularly the surface on the heat seal layer side.

Therefore, for example, in a pillow bag or the like made by using the composite film of the present invention, it is necessary to provide a half cut along a heat-sealed portion, particularly a region intended to be opened by peeling off the heat-sealed portion. However, since the alignment operation is not required at the time of heat sealing, it can contribute to productivity.

Further, when a package such as a resealable packaging bag is produced using the composite film of the present invention, it is possible to suppress a decrease in the reseal strength even when the number of resealings increases. ..

In addition, when a package such as a package containing contents filled with contents is produced using the composite film of the present invention, a rubber band, a clip, or the like should be used when the contents are stored again after opening. It will be possible to reseal without any. Furthermore, since it is possible to form a packaging bag that can be resealed without using a separate member such as a chuck tape, it is possible to provide a packaging body that is cost- and environmentally friendly, such as reducing the amount of resin material used and simplifying the work process. Can be done.

Further, when the outer layer is a transparent layer rather than the aluminum layer of the composite film of the present invention, it is possible to confirm from the outside of the packaging bag that the aluminum layer is broken when the package such as the packaging bag is opened. can. Therefore, whether the packaging bag or the like is in an unopened state or an opened and resealed state can be visually recognized from the outside of the packaging body such as the packaging bag or the like. This can also help prevent tampering in the store.

It is sectional drawing of the composite film which concerns on one Embodiment of this invention. It is a figure which shows the peeling mechanism at the time of opening the container with a lid containing contents which concerns on one Embodiment of this invention. 6 is a graph showing the relationship between the number of resealings of the composite films of Example 1 and Comparative Example 1 and the opening strength. It is a schematic diagram of the packaging bag containing contents which concerns on one Embodiment of this invention.

《Composite film》
The composite film of the present invention is a composite film in which at least a base material layer, an adhesive layer, an aluminum layer, and a heat seal layer are laminated in this order, and the adhesive layer and the aluminum layer are adjacent to each other. .. Further, in the composite film of the present invention, when the heat-sealed layers are heat-sealed and peeled off from each other, or when the heat-sealed layer and another material are heat-sealed and peeled off, at the edge of the heat-sealed portion. Delamination occurs between the adhesive layer and the aluminum layer at the portion where the aluminum layer and the heat-sealed layer are broken and heat-sealed.

In the composite film of the present invention, since the adhesive layer and the aluminum layer are adjacent to each other, the heat-sealing layer is heat-sealed on the container body or the like to form a resealable package, and when the package is opened. At the edge of the heat-sealed portion of the container body or the like, the aluminum layer and the heat-sealed layer are broken, and at the heat-sealed portion of the container body or the like, delamination occurs between the adhesive layer and the aluminum layer. It is possible to prevent the adhesive layer from remaining on the container body side.

In the present invention, the breakage of the aluminum layer and the heat-sealed layer at the edge of the heat-sealed portion of the container body or the like may be referred to as “edge breakage”. By utilizing such edge breakage, the composite film of the present invention can produce a resealable lid material or the like even when a half cut is not used on the heat seal layer side.

The composite film of the present invention suppresses the adhesive layer from coming into contact with the lips when applied as a lid material for a container such as a cup soup to be eaten with the mouth attached to the container, thereby avoiding discomfort in the mouthfeel and the like. can do.

Further, when a resealable package is produced using the composite film of the present invention, it is possible to suppress a decrease in resealing strength even when the number of resealings increases.

In addition, in this specification, "adjacent" means that they are in direct contact with each other, and means that they are in contact with each other without interposing another layer such as an adhesive layer.

<< Composition of composite film >>
Hereinafter, the configuration of the composite film of the present invention will be described with reference to the drawings. FIG. 1 shows a cross-sectional view according to an embodiment of the composite film of the present invention.

The composite film 10 according to an embodiment of the composite film of the present invention shown in FIG. 1 has a first base material layer 1 and a second base material layer laminated inside the first base material layer 1. 2, an adhesive layer 3 laminated and arranged inside the second base material layer 2, an aluminum layer 4 arranged adjacent to the adhesive layer 3, and a heat seal laminated and arranged inside the aluminum layer 4. Layer 5 and the like. That is, the composite film 10 shown in FIG. 1 has an embodiment having two base layers.

The composite film of the present invention includes a base material layer, an adhesive layer, an aluminum layer, and a heat seal layer as essential configurations, and these are laminated in this order. In the present invention, any layer may be provided in addition to the base material layer, the adhesive layer, the aluminum layer, and the heat seal layer, and the arbitrary layer may be, for example, a barrier layer for imparting barrier properties. , A reinforcing layer for reinforcing the strength, an adhesive layer for adhering between the layers, and the like.

The composite film 10 shown in FIG. 1 includes only a first base material layer 1, a second base material layer 2, an adhesive layer 3, an aluminum layer 4, and a heat seal layer 5, but the adhesive layer 3 is provided. Other layers may be present in the layers other than between the aluminum layer 4 and the outside of the laminated body.

The thickness and the like of each layer constituting the composite film of the present invention can be appropriately determined according to the use and the like of the composite film.

<Base layer>
The base material layer is an essential constituent layer in the composite film of the present invention.

In the composite film of the present invention, the base material layer, the adhesive layer, the aluminum layer, and the heat seal layer are laminated in this order. Therefore, when the base material layer forms a structure such as a package, for example, when the base material layer is formed. It is the outer layer of the structure. Therefore, the base material layer can be a protective layer when the innermost heat seal layer is heat-sealed to form a structure. It can also serve as a printing layer for printing for displaying the contents and the like.

The base material layer may be a single layer or a laminated body composed of a plurality of layers. Alternatively, two or more base material layers may be present.

When the base material layer is a single layer, the material constituting the base material layer may be a resin, particularly a resin that serves as a protective layer and enables printing. Commonly used resins can be used, for example, polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polyethylene (PE), polypropylene (PP). , Polyethylene (PS) and the like, Nylon-6, Nylon-66 and the like polyamide (PA), Polypropylene (PC) and the like.

The above resin may be blended with not only one type but also two or more types, and if necessary, an additive or the like for imparting functionality or the like may be blended.

Among them, the resin constituting the base material layer is preferably polyester from the viewpoint of improving the adhesiveness between the base material layer and the adhesive layer. Further, polyethylene terephthalate (PET) is particularly preferable from the viewpoints of printability, imparting rigidity to the composite film, easy availability, and handleability.

When the base material layer is a resin layer, a preformed film may be applied. The film to be the base material layer may be a film formed from the above resin or the like, and may be unstretched or may be uniaxially or biaxially stretched. Among them, a biaxially stretched film is preferable.

Further, the resin film to be the base material layer may be formed with an inorganic material vapor-deposited film on which a metal such as aluminum or an inorganic substance such as silicon oxide or aluminum oxide is vapor-deposited. Alternatively, it may have a barrier coat layer such as a vinylidene chloride coat layer and a polyvinylidene fluoride coat layer.

Further, the resin film to be the base material layer may be subjected to a roughening treatment for roughening the surface thereof. Since the surface is roughened, an anchor effect with the adjacent adhesive layer is generated, and the adhesion can be improved.

When the composite film of the present invention has two or more base material layers, it has another base material layer in addition to the above-mentioned single layer. In this case, a plurality of layers made of the above resin or the like may be provided, or a layer made of a material other than the resin may be used.

Examples of the layer made of a material other than the resin include a paper layer and the like. Examples of the paper layer include coated paper and art paper. Further, when the paper layer is the outermost layer as the base material layer, printing such as gravure printing or flexographic printing may be performed.

<Adhesive layer>
The adhesive layer is an essential constituent layer in the composite film of the present invention, and the adhesive layer is adjacent to the aluminum layer.

In the composite film of the present invention, the heat-sealed layers or the heat-sealed layers are heat-sealed with other materials such as a container body to form a resealable package, and when the package is opened, the adhesive layer is formed. , Delamination occurs with the aluminum layer adjacent to the adhesive layer.

The adhesive layer can be produced, for example, by preparing a composition as a material for the adhesive layer and applying it to the surface of the layer to be laminated by printing means. As the printing means, for example, gravure printing, offset printing, flexographic printing, silk printing and the like can be used.

The thickness of the adhesive layer is preferably 5 μm or less. If it is 5 μm or less, the heat-sealed layer is heat-sealed to form a resealable package, and when the package is opened, delamination between the adhesive layer and the aluminum layer adjacent to the adhesive layer is performed. Can be done more easily.

The thickness of the adhesive layer may be 4 μm or less, or 3 μm or less, and is preferably 1 μm or more, 1.5 μm or more, or 2 μm or more from the viewpoint of obtaining sufficient resealability.

The pressure-sensitive adhesive layer may be, for example, a layer containing a thermoplastic elastomer and / or an amorphous polyester, and may further contain a polyterpene and / or a rosin ester as a pressure-sensitive adhesive. Among them, an embodiment containing a thermoplastic elastomer and a polyterpene and / or a rosin ester as a tackifier, an embodiment in which only an amorphous polyester is a constituent material, or an amorphous polyester and a rosin ester as a tackifier. A mode including is preferable. The materials that can form the adhesive layer will be described below.

(Thermoplastic elastomer)
The thermoplastic elastomer that can be a constituent of the pressure-sensitive adhesive layer of the composite film of the present invention is a material that can be fluidized and molded at a high temperature and exhibits rubber elasticity at a normal temperature. The thermoplastic elastomer applicable to the present invention is not particularly limited, and examples thereof include olefin-based thermoplastic elastomers and styrene-based thermoplastic elastomers.

Examples of the olefin-based thermoplastic elastomer include ethylene-propylene copolymer (EPM), ethylene-butene copolymer (EBM), ethylene-octene copolymer, ethylene-propylene-butene copolymer, and propylene-butene. Examples include polymers, ethylene-propylene-diene copolymers (EPDM) and the like.

It is also possible to use a blend type olefin-based thermoplastic elastomer in which an olefin-based rubber (EPM, EPDM, etc.) is dispersed in a matrix of an olefin-based resin (for example, polypropylene, polyethylene, etc.).

Examples of the styrene-based thermoplastic elastomer include styrene-ethylene-butene copolymer (SEB), styrene-ethylene-propylene copolymer (SEP), styrene-ethylene-butene-styrene copolymer (SEBS), and styrene-ethylene. -Protein-styrene copolymer (SEPS), styrene-ethylene-ethylene-propylene-styrene copolymer (SEEPS), styrene-butadiene-butylene-styrene copolymer (partially hydrogenated styrene-butadiene-styrene copolymer; SBBS), partially hydrogenated styrene-isoprene-styrene copolymer, partially hydrogenated styrene-isoprene butadiene-styrene copolymer and the like can be mentioned.

The thermoplastic elastomer that can be a constituent component of the pressure-sensitive adhesive layer of the present invention may be a styrene-based thermoplastic elastomer because it exhibits rubber elasticity in the normal temperature or high temperature region.

Further, since the compatibility with the tackifier is good, a styrene-butadiene / butylene-styrene copolymer may be used among the styrene-based thermoplastic elastomers.

The content of the thermoplastic elastomer in the adhesive layer may be 30% by mass or more, 35% by mass or more, 40% by mass or more, or 45% by mass or more, and 70% by mass or less, based on the total mass of the adhesive layer. It may be 65% by mass or less, 60% by mass or less, or 55% by mass or less.

(Amorphous polyester)
The amorphous polyester that can be a constituent of the adhesive layer of the composite film of the present invention is an amorphous polyester.

Here, "amorphous" in the present invention does not have a clear melting peak when the temperature is raised from -100 ° C to 300 ° C at a rate of 20 ° C / min using a differential scanning calorimeter (DSC). Means that.

The amorphous polyester that can be a constituent of the adhesive layer of the composite film of the present invention is not particularly limited, but may have, for example, a glass transition temperature of 60 ° C. or lower. The glass transition temperature may be 60 ° C. or lower, 55 ° C. or lower, or 50 ° C. or lower, and is −65 ° C. or higher, −50 ° C. or higher, −40 ° C. or higher, −30 ° C. or higher, or −20 ° C. or higher. There may be.

If the glass transition temperature is an amorphous polyester in the above range, it is possible to realize a composite film having good resealability while causing delamination between the adhesive layer and the aluminum layer without any practical problem. Can be done.

Further, the glass transition temperature of the amorphous polyester is preferably 45 ° C. or lower from the viewpoint of preventing peeling (pulse peeling) accompanied by abnormal noise or catching at the time of opening, that is, from the viewpoint of causing smooth peeling. .. Further, from the viewpoint of obtaining good peelability at room temperature, the glass transition temperature is −65 ° C. or higher, −50 ° C. or higher, −20 ° C. or higher, −10 ° C. or higher, 0 ° C. or higher, 10 ° C. or higher, 20 ° C. or higher. , Or 25 ° C. or lower is preferable.

The glass transition temperature (Tg) in the present specification is determined by heat flow differential scanning calorimetry (heat flux DSC) under a heating condition of a heating rate of 10 ° C./min in accordance with JISK7121 (1987). The intermediate point glass transition temperature (° C) is referred to, and JIS K7121 "when measuring the glass transition temperature after performing a certain heat treatment" shall be adopted for adjusting the state of the test piece.

The number average molecular weight of the amorphous polyester is not particularly limited, but for example, if it is 100,000 or less, 90,000 or less, 80,000 or less, 70,000 or less, 60,000 or less, or 50,000 or less, the adhesive layer and the aluminum layer may be used. After delamination between, the stickiness of the exposed adhesive layer can be suppressed. On the other hand, if it is 5000 or more, 6000 or more, 7000 or more, 8000 or more, 9000 or more, or 10000 or more, an appropriate peel strength can be ensured.

Here, the number average molecular weight in the present specification means the number average molecular weight measured by gel permeation chromatography in a tetrahydrofuran solvent and a polystyrene standard.

The amorphous polyester that can be a constituent of the adhesive layer of the composite film of the present invention is an amorphous polyester containing 50 mol% of a dicarboxylic acid component and 50 mol% of a diol component, and is 30 mol% or more. It may be an amorphous polyester containing terephthalic acid, 25 mol% or more of ethylene glycol, and 5 to 45 mol% of other dicarboxylic acid components and / or other diol components.

Examples of other dicarboxylic acid components include isophthalic acid, orthophthalic acid, 1,5-naphthalic acid, 2,6-naphthalic acid, 4,4'-diphenyldicarboxylic acid, 2,2'-diphenyldicarboxylic acid, 4, Aromatic dibasic acids such as 4'-diphenyl ether dicarboxylic acid, adipic acid, azelaic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4-methyl Examples thereof include aliphatic and alicyclic dicarboxylic acids such as -1,2-cyclohexanedicarboxylic acid and dimer acid.

Examples of other diol components include propylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 1,4-butanediol. , 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 2,2,4-trimethyl-1,3-pentanediol , Cyclohexanedimethanol, neopentyl hydroxypivalic acid ester, 1,9-nonanediol, 2-methyloctanediol, 1,10-dodecanediol, 2-butyl-2-ethyl-1,3-propanediol, tricyclode Candiethanol and the like can be mentioned.

The content of amorphous polyester in the adhesive layer is 50% by mass or more, 60% by mass or more, 75% by mass or more, 80% by mass or more, 85% by mass or more, 90% by mass or more with respect to the total mass of the adhesive layer. , 95% by mass or more, or 100% by mass, and may be 99% by mass or less, 97% by mass or less, 95% by mass or less, 93% by mass or less, or 91% by mass or less.

The amorphous polyester that can form the adhesive layer of the composite film of the present invention may be used alone or in combination of two or more kinds of amorphous polyester. When two or more kinds of amorphous polyesters are used in combination, they can also be used as a mixture of amorphous polyesters having different physical characteristics such as different Tg.

(Polyterpen)
The polyterpene that can be a constituent of the adhesive layer of the composite film of the present invention is used by being blended with the above-mentioned thermoplastic elastomer and / or amorphous polyester. Polyterpene is an organic compound having isoprene as a basic skeleton in its molecular structure.

The inclusion of the polyterpen in the adhesive layer can provide good resealability between the adhesive layer and the aluminum layer. Further, even when the number of resealings increases, it is possible to suppress a decrease in the resealing strength.

The polyterpen applicable to the present invention is not particularly limited, and commercially available polyterpen can be used. For example, Sylvares (registered trademark) TRA25, TRB115, TR1115T, TR7115, TRM1115, TR7125, TRB125, TR1135, TR90, TR105, etc., which are commercially available from Clayton, can be mentioned.

The content of polyterpene in the adhesive layer may be 30% by mass or more, 35% by mass or more, 40% by mass or more, or 45% by mass or more, and 70% by mass or less, 65% by mass, based on the total mass of the adhesive layer. % Or less, 60% by mass or less, or 55% by mass or less.

The polyterpen that can form the adhesive layer of the composite film of the present invention may be used alone or in combination of two or more types.

(Rodin ester)
The rosin ester, which can be a constituent of the pressure-sensitive adhesive layer of the composite film of the present invention, is used by being blended with the above-mentioned thermoplastic elastomer and / or amorphous polyester. A rosin ester is a compound in which rosin is esterified.

The adhesiveness of the adhesive layer can be improved by containing a sufficient amount of rosin ester in the adhesive layer, and the strength of the adhesive layer is maintained by preventing the amount of rosin ester from becoming excessive. can do.

The type of resin acid (various isomers) that is the main component of the rosin to be esterified is not particularly limited, and even if it is a conjugated resin acid having a conjugated double bond, it is a non-conjugated resin acid. Also may be a mixture thereof.

Examples of the conjugated resin acid include abietic acid, neo-abietic acid, and palastolic acid. Examples of the non-conjugated resin acid include pimaric acid, isopimaric acid, dehydroabietic acid and the like.

The form of the rosin ester is not particularly limited, and for example, an ester of rosin or polymerized rosin and a polyhydric alcohol, an ester of hydrogenated rosin, and a maleic acid-modified rosin obtained by adding maleic acid to the ester. It may be an ester or the like.

It may be commercially available as a "rosin ester", and examples thereof include Haritac series manufactured by Harima Chemicals, ester gum series manufactured by Arakawa Chemicals, and Pencel (registered trademark) series. ..

The content of the rosin ester in the adhesive layer may be 1% by mass or more, 3% by mass or more, 5% by mass or more, 7% by mass or more, or 9% by mass or more, 50% by mass, based on the total mass of the adhesive layer. It may be mass% or less, 40% by mass or less, 25% by mass or less, 20% by mass or less, 15% by mass or less, 10% by mass or less, or 5% by mass or less.

The rosin ester constituting the adhesive layer of the composite film of the present invention may be used alone or in combination of two or more kinds of rosin esters.

(Other ingredients)
The adhesive layer of the composite film of the present invention may contain other resins or the like or additives for imparting functionality or the like, if necessary.

<Aluminum layer>
The aluminum layer is an essential constituent layer in the composite film of the present invention, and is a layer adjacent to the above-mentioned adhesive layer.

In the composite film of the present invention, the heat-sealed layers or the heat-sealed layers are heat-sealed with other materials such as a container body to form a resealable package, and when the package is opened, the aluminum layer is formed. , Delamination occurs between the adhesive layer adjacent to the aluminum layer.

When the heat-sealing layer is heat-sealed with the container body or the like, the delaminated aluminum layer is exposed and exists at the joint portion on the container body side formed by the heat-sealing after opening.

Therefore, in the composite film of the present invention, the aluminum layer serves as a peeling interface when forming a resealable package. At the same time, the aluminum layer also functions as a barrier layer for blocking the permeation of gas in the composite film of the present invention, and can particularly improve the gas barrier property of the package before opening.

As the material constituting the aluminum layer, for example, an aluminum foil can be applied.

The thickness of the aluminum layer is not particularly limited, but is preferably 3 μm or more, 5 μm or more, or 7 μm or more, for example, from the viewpoint of ensuring strength and barrier properties. Further, it is preferably 20 μm or less, 15 μm or less, or 12 μm or less from the viewpoint of improving the handleability and the ease of edge cutting when the composite film is used as a packaging material or the like.

<Heat seal layer>
The heat seal layer is an essential constituent layer in the composite film of the present invention. The heat-sealed layer is a layer to be heat-sealed when a package or the like is formed by using the composite film of the present invention. Therefore, the heat seal layer is arranged so as to be the innermost layer of the composite film.

The material constituting the heat seal layer is not particularly limited as long as it can be heat-bonded and can impart sufficient seal strength to the formed structure. Known materials can be applied, such as low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), polypropylene (PP), ethylene- Examples thereof include propylene copolymer (EP), ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer (EMAA), ionomer resin, ethylene-vinyl acetate copolymer (EVA) and the like.

When it is desired to impart content resistance, it is preferable to use, for example, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), or the like.

The heat seal layer may be formed by using a preformed film, or is formed by melting and extruding a material for forming the heat seal layer on the surface of the target laminate and cooling and solidifying the material. You may.

The resin or the like constituting the heat seal layer may be a blend of not only one type but also two or more types, and if necessary, an additive or the like for imparting functionality or the like is blended. May be good.

The heat-sealing layer constituting the composite film of the present invention may be, among others, the first heat-sealing layer or the second heat-sealing layer described below.

[First heat seal layer]
The first heat seal layer is a layer containing a polyolefin resin and having a thickness of 1 to 7 μm.

If the heat-sealing layer contains a polyolefin resin and has a thickness of 1 to 7 μm, the thickness is thin, and the heat-sealing layer is crushed by the pressure of the heat-sealing bar during heat-sealing to become even thinner. As a result, it becomes brittle, so that edge cutting can be performed more easily.

The thickness of the first heat seal layer may be 6 μm or less, 5 μm or less, or 4 μm or less, and may be 1 μm or more, 2 μm or more, or 3 μm or more.

(Polyolefin resin)
The polyolefin resin used as the material of the first heat seal layer is not particularly limited, and is, for example, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), and the like. Examples thereof include high density polyethylene (HDPE), polypropylene (PP), ethylene-propylene copolymer (EP), polystyrene (PS) and the like.

Above all, the acid-modified polyolefin-based resin is preferable from the viewpoint of having both the coatability of the heat-sealing layer and the heat-sealing property and making it easier to cut the edge.

The polyolefin-based resin constituting the first heat-seal layer may be blended with not only one type but also two or more types, and if necessary, an additive or the like for imparting functionality or the like is blended. May be.

[Second heat seal layer]
The second heat seal layer is a polyethylene resin layer having a density of 0.920 to 0.958 g / cm ³ . According to such a configuration, it is possible to provide sufficient film forming property and heat sealing property, and to make edge cutting easier.

In the present invention, the density may be a value measured according to JIS K7112-1999.

The density of the second heat seal layer is 0.920 to 0.958 g / cm3. The density of the second heat seal layer is 0.923 g / cm ³ or more, 0.925 g / cm ³ or more, 0.927 g / cm ³ or more, 0.930 g / cm ³ or more, 0.933 g / cm ³ or more, Alternatively, it may be 0.935 g / cm ³ or more, 0.952 g / cm ³ or less, 0.950 g / cm ³ or less, or 0.948 g / cm ³ or less.

The resin constituting the polyethylene resin layer to be the second heat seal layer may be a blend of not only one type but also two or more types, and if necessary, an additive or the like for imparting functionality or the like. May be blended.

The thickness of the second heat seal layer is not particularly limited, and may be, for example, 1 μm or more, 2 μm or more, or 3 μm or more. This thickness is preferably less than 10 μm, 7 μm or less, 6 μm or less, or 5 μm or less from the viewpoint of facilitating edge cutting.

The polyethylene resin layer to be the second heat seal layer is preferably a mixed resin layer containing high-density polyethylene and low-density polyethylene. A mixed resin layer containing high-density polyethylene and low-density polyethylene can improve the film-forming property.

Whether or not the polyethylene resin layer to be the heat seal layer is a mixed resin layer containing high-density polyethylene and low-density polyethylene is determined by measuring the mixed resin layer using, for example, differential scanning calorific value measurement (DSC). , Can be confirmed by comparing with the curves measured for each polyethylene constituting the mixed resin layer.

When the polyethylene resin layer to be the second heat seal layer is a mixed resin layer containing high-density polyethylene and low-density polyethylene, the above density weights the density of each component by the content rate of each component. It may be a weighted average.

(High density polyethylene)
In the present specification, high-density polyethylene includes, if it has a branched chain, the branching difference thereof, and contains or substantially 80 mol% or more, 90 mol% or more, 95 mol% or more, or 98 mol% or more of the repeating unit of the methylene group. Refers to polyethylene having a density of 0.942 g / cm ³ or more, in which all repeating units are methylene groups.

In particular, 0.942 g / cm ³ or more, 0.945 g / cm ³ or more, 0.948 g / cm ³ or more, 0.950 g / cm ³ or more, 0.952 g / cm ³ or more, or 0.955 g / cm ³ or more. It has a density of 2 and substantially does not have a long-chain branched structure, and is obtained by radically polymerizing ethylene by a low-pressure method.

The density of high-density polyethylene is 0.970 g / cm ³ or less, 0.967 g / cm ³ or less, 0.965 g / cm ³ or less, 0.962 g / cm ³ or less, or 0.960 g / cm ³ or less. good.

The thermal properties of the preferred high-density polyethylene are not particularly limited, but for example, under the conditions that the melt mass flow rate is 190 ° C. and the load is 21.18 N, JIS K6922-1 and -2, and When measured in accordance with JIS K7210-1, it is preferably 0.1 g / 10 min or more, 0.5 g / 10 min or more, 1.0 g or more, 3.0 g / 10 min or more, or 5.0 g / 10 min or more. , 100 g / 10 min or less, 50 g / 10 min or less, 30 g / 10 min or less, or 20 g / 10 min or less.

When the polyethylene resin layer to be the second heat-sealing layer is a mixed resin layer containing high-density polyethylene and low-density polyethylene, the content of high-density polyethylene in the heat-sealing layer is the total mass of the heat-sealing layer. It is preferably 50 to 90% by mass.

Further, the content of the high-density polyethylene may be 55% by mass or more, 60% by mass or more, or 65% by mass or more, and 85% by mass or less and 80% by mass or less with respect to the total mass of the heat seal layer. , Or 75% by mass or less.

(Low density polyethylene)
In the present specification, low-density polyethylene (LDPE) contains 80 mol% or more, 90 mol% or more, 95 mol% or more, or 98 mol% or more, or substantially all of the repeating units of methylene groups, including branched chains. Refers to polyethylene having a density of less than 0.930 g / cm ³ and having a methylene group as the repeating unit.

The density of the low density polyethylene may be 0.925 g / cm ³ or less, or 0.923 g / cm ³ or less, 0.870 g / cm ³ or more, 0.875 g / cm ³ or more, 0.880 g / cm. It may be ³ or more, 0.900 g / cm ³ or more, 0.910 g / cm ³ or more, or 0.915 g / cm ³ or more.

The low density polyethylene may be so-called linear low density polyethylene (LLDPE), or may have a long-chain or short-chain branched structure. The short-chain branched structure is composed of α-olefins having 4 to 18, 4 to 10 or 4 to 8 carbon atoms, such as 1-butene, 1-hexene, 4-methylpentene-1, 1-octene and the like. It may be a branched structure from which it is derived.

The thermal properties of the preferred low density polyethylene are not particularly limited, but are, for example, JIS K6922-1 and -2, and under the condition that the melt mass flow rate is 190 ° C. and a load of 21.18 N. When measured in accordance with JIS K7210-1, it is preferably 0.1 g / 10 min or more, 0.5 g / 10 min or more, 1.0 g or more, 3.0 g / 10 min or more, or 5.0 g / 10 min or more. , 100 g / 10 min or less, 50 g / 10 min or less, 30 g / 10 min or less, or 20 g / 10 min or less.

The content of low-density polyethylene in the heat-sealed layer is not particularly limited, but is, for example, 10% by mass or more, 15% by mass or more, 20% by mass or more, or 25 with respect to the total mass of the heat-sealing layer. It may be 50% by mass or less, 45% by mass or less, 40% by mass or less, or 35% by mass or less.

<Other layers>
The composite film of the present invention includes a base material layer, an adhesive layer, an aluminum layer, and a heat seal layer in this order, and includes layers other than these if the adhesive layer and the aluminum layer are adjacent to each other. May be. The other layers can be arranged between the base material layer and the adhesive layer, which are essential constituent layers, between the aluminum layer and the heat seal layer, or outside the laminate containing these layers. ..

The other layers are not particularly limited, and are, for example, a barrier layer for imparting barrier properties, a reinforcing layer for reinforcing strength, or an adhesion for adhering between layers. Layers and the like can be mentioned.

Examples of the barrier layer for imparting barrier properties include ethylene-vinyl alcohol copolymer (EVOH), nylon (NY), and polyvinylidene chloride (PVDC), which exhibit a function of blocking gases such as oxygen and water vapor. , Or a layer made of polyacrylonitrile (PAN) and the like.

Alternatively, as described above, the inorganic material vapor deposition layer or the organic material coat layer may be formed on the base material layer to impart barrier properties.

Further, a metal foil other than the aluminum foil may be present as the barrier layer. Examples of the metal foil other than the aluminum foil include metal foils such as copper foil and titanium foil, alloy foils such as aluminum alloy foils and stainless steel foils, and the like.

When an inorganic vapor-deposited film or an organic coat layer is present as the barrier layer, the thickness of the barrier layer should be 100 nm or more, 200 nm or more, 300 nm or more, 500 nm or more, 700 nm or more, or 1 μm or more for strength and barrier. It is preferable from the viewpoint of ensuring the properties, and 5 μm or less, 4 μm or less, 3 μm or less, or 2 μm or less is preferable from the viewpoint of improving the handleability when the composite film is used as a packaging material or the like.

When the metal foil is present as the barrier layer, the thickness of the barrier layer is preferably 3 μm or more, 5 μm or more, 7 μm or more, 10 μm or more, or 15 μm or more from the viewpoint of ensuring strength and barrier property. Further, it is preferable that the thickness is 100 μm or less, 80 μm or less, 60 μm or less, 55 μm or less, 50 μm or less, 45 μm or less, 40 μm or less, or 35 μm or less from the viewpoint of improving the handleability when the composite film is used as a packaging material or the like.

Examples of the material of the reinforcing layer for reinforcing the strength include paper, synthetic paper, and non-woven fabric. These may be coated with an adhesive for imparting adhesiveness to adjacent layers.

Examples of the adhesive layer for adhering between the layers include a layer composed of an ethylene-acrylic acid copolymer (EAA), an ethylene-methacrylic acid copolymer (EMAA), and an ionomer.

The adhesive layer may be a layer made of an adhesive used for dry laminating or hot melt laminating the layers constituting the laminate to be the composite film of the present invention. For example, it may be a dry laminate adhesive, a hot melt adhesive, a water-soluble adhesive, an emulsion adhesive, a non-solvent laminate adhesive, a thermoplastic resin for extrusion lamination, or the like.

The resin or the like constituting the other layer may be a blend of not only one type but also two or more types. Further, if necessary, an additive or the like for imparting functionality or the like may be blended.

<< Manufacturing method of composite film >>
The method for producing the composite film of the present invention is not particularly limited as long as it can form a laminated composite film. Known methods can be adopted, and examples thereof include a dry lamination method, a hot melt lamination method, an extrusion lamination method, and a sandwich lamination method.

<< Applications of composite film >>
The use of the composite film of the present invention is not particularly limited. For example, it can be used as a packaging material, for example, a lid material or the like is formed, and the heat seal layer of the lid material and another material such as a container body are heat-sealed to form a container with a lid containing contents. May be good. Alternatively, the heat-sealing layers may be heat-sealed with each other or another material such as a film to form a packaging bag or the like.

<Cover material>
The structure formed by using the composite film of the present invention may be a lid material. The lid material formed from the composite film of the present invention can be, for example, a lid material for sealing the upper end opening of the container body. Since the lid material formed from the composite film of the present invention becomes a resealable lid material, it is possible to form a resealable packaged container with a lid.

The lid material formed from the composite film of the present invention can be heat-sealed to, for example, the upper end opening of the container body to form a packaged container with a lid, and when the packaged container is opened, the aluminum layer and the heat-sealed layer can be formed. The adhesive layer can be resealed with the aluminum layer due to the outer edge breakage due to breakage, the delamination between the adhesive layer and the aluminum layer constituting the lid material, and the inner edge breakage due to the breakage of the aluminum layer and the heat seal layer. It is exposed in a state of being. Then, when the packaging container is resealed, it will be resealed between the adhesive layer and the aluminum layer.

That is, in a package formed by heat-sealing the heat-sealing layer of the composite film of the present invention on a container body or the like, the aluminum layer and the heat-sealing layer are formed on the outer and inner edges of the heat-sealed joint. Since it is broken and opened, it is not necessary to provide a notch (half cut) formed at a depth less than the thickness of the composite film from the surface of the composite film, particularly the surface on the heat seal layer side.

The resealable packaged container with a lid formed by using the composite film of the present invention is a packaged container in which a decrease in resealing strength is suppressed even when the number of resealings is increased.

<Container with lid containing contents>
The structure formed by using the composite film of the present invention may be a container with a lid containing contents.

Specifically, the container body having the storage portion and the flange portion, the contents housed in the container body, and the lid material formed from the composite film of the present invention are provided, and the heat seal layer of the lid material is provided. A container with a lid containing contents, which is heat-sealed on the flange of the container body to form a resealable joint.

In the container with a lid containing the contents formed by using the lid material formed from the composite film of the present invention, the joint portion where the lid material is heat-sealed can be resealed.

Specifically, the container with a lid containing the contents formed by using the lid material formed from the composite film of the present invention has edge breakage and delamination between the adhesive layer and the aluminum layer at the time of opening. Happens. After opening, the delaminated aluminum layer is exposed at the joint portion on the container body side formed by the heat seal, and the adhesive layer remains on the lid material side.

Thereby, for example, when the lid material formed from the composite film of the present invention is applied to a food container or the like, the adhesive layer does not come into contact with the human body, and it is possible to avoid a feeling of strangeness in the mouthfeel or the like.

Then, at the time of resealing, it can be resealed between the adhesive layer remaining on the lid material side and the aluminum layer exposed on the container body side.

The container with a lid containing resealable contents formed by using the composite film of the present invention is a packaging container in which a decrease in resealing strength is suppressed even when the number of resealings increases.

Further, in the container with a lid containing resealable contents formed by using the composite film of the present invention, the base material layer and the adhesive layer of the composite film are transparent, and the outer layer is more transparent than the aluminum layer. If so, the aluminum layer can be visually recognized from the base material layer side.

This makes it possible to confirm from the outside of the package that the aluminum layer has broken when the package is opened, and whether the package is in an unopened state or in an opened and resealed state. It can be seen from the outside of the body.

[Action of container with lid containing contents]
Hereinafter, the operation of the container with a lid containing the contents formed by using the composite film of the present invention will be described with reference to the drawings.

FIG. 2 is a diagram showing a peeling mechanism when a container with a lid containing contents according to an embodiment of the present invention is opened.

The container with a lid containing the contents formed by using the composite film of the present invention is produced by heat-sealing the heat-sealing layer, which is the innermost layer of the composite film of the present invention, on the flange portion of the container body having a flange. Can be done.

The container with a lid containing the contents according to the embodiment of the present invention shown in FIG. 2 is a container body having a flange portion 202 in which the lid material 100 formed from the composite film of the present invention is stored and the contents 250 are stored. It is manufactured by heat-sealing the flange portion 202 of 200 to form the joint portion 202a.

The lid material 100 formed from the composite film of the present invention shown in FIG. 2 has a first base material layer 101 and a second base material layer 102 laminated and arranged inside the first base material layer 101. , The adhesive layer 103 laminated and arranged inside the second base material layer 102, the aluminum layer 104 arranged adjacent to the adhesive layer 103, and the heat seal layer 105 laminated and arranged inside the aluminum layer 104. And. That is, the lid material 100 shown in FIG. 1 has an embodiment having two base material layers.

The container with a lid containing the contents formed by using the lid material 100 according to the embodiment of the present invention having the above aspect, when opened, protrudes from the flange portion 202 as shown in FIG. 2A. By picking up the tab 110 and pulling up the lid material 100, the heat seal layer 105 and the aluminum layer 104 are broken (outer edge cut) at a position corresponding to the outer periphery of the joint portion 202a, and the first position corresponding to this position is obtained. The broken portion 120a is exposed.

Further, when the lid material 100 is pulled up, as shown in FIG. 2B, the lid material 100 is delaminated at the interface between the adhesive layer 103 and the aluminum layer 104. After that, when the delamination reaches the position corresponding to the inner circumference of the joint portion 202a, the heat seal layer 105 and the aluminum layer 104 are broken (inner edge cut) as shown in FIG. 2C, and this position is reached. The second broken portion 120b corresponding to the above is exposed, and the resealing portion 106 is formed on the flange portion 202 of the container body 200.

That is, the resealing portion 106 is a laminated body composed of a heat seal layer 105 and an aluminum layer 104 formed by delamination from the lid material 100 in the region of the joint portion 202a formed on the flange portion 202, and is an aluminum layer 104. Is exposed on the surface.

Then, when the opened container with a lid containing the contents 300 is resealed, the adhesive layer 103 and the aluminum layer 104 are resealed by pressing the lid material 100 against the resealing portion 106.

[Construction of container with lid containing contents]
The container with a lid containing the contents includes a container body, the contents, and a lid material formed from the composite film of the present invention.
(Container body)
The container body for forming a container with a lid containing contents has a storage portion and a flange portion.

The material of the container body is not particularly limited, as long as the heat-sealing layer of the lid material formed from the composite film of the present invention can be heat-sealed. For example, a paper container whose surface is coated with a resin, a resin container, or the like can be mentioned.

{Storage unit}
The storage unit is a portion where the contents are stored. The shape of this portion is not particularly limited, and may be, for example, a substantially conical trapezoid, a polygonal pyramid trapezoid, a rectangular parallelepiped shape, a cube shape, or the like.

{Flange part}
The flange portion is a portion around the upper end opening of the storage portion of the container body. The shape is not particularly limited, and may be, for example, a brim shape. Further, the shape of the outer periphery of the flange portion can be appropriately selected according to the shape of the lid material.

Among them, it is preferable that at least the flange portion of the container has a coating made of a polyethylene resin. Further, it is preferable that the container body is a paper cup and the flange portion is coated with a polyethylene resin.

If the container body is a paper cup having a flange portion coated with polyethylene resin, the adhesive layer and the heat-sealing layer of the lid material formed from the composite film of the present invention can be obtained while obtaining a certain sealing strength. At the interface with the aluminum layer, delamination can be performed smoothly.

(Contents)
The contents are those housed in the storage unit. The contents are not particularly limited, and examples thereof include heated foods such as soups, instant noodles, chilled foods, and frozen foods, and non-heated foods such as snack foods and gummy candies.

<Packaging bag>
The composite film of the present invention may be used for forming a packaging bag. For example, by heat-sealing the heat-sealing layers of the composite film of the present invention with each other, or by heat-sealing the heat-sealing layer of the composite film of the present invention with another material such as a film, a three-way sealing bag or a four-way sealing can be performed. Bags, gusset packaging bags, pillow packaging bags, gable top type bottomed containers, Tetra Classic (registered trademark), brick packs (registered trademark), tube containers and the like can be formed.

The packaging bag formed from the composite film of the present invention is opened because the aluminum layer and the heat-sealing layer are broken and opened at one or both of the outer edge and the inner edge of the heat-sealed joint. It is not necessary to provide a notch (half cut) for use in opening from the surface on the heat seal layer side of the above.

<Packaging bag with contents>
The composite film of the present invention may be used for forming a packaging bag containing contents. For example, by heat-sealing the heat-sealing layer of the composite film and filling it with the contents, a packaging bag filled with the contents can be obtained.

FIG. 4 shows a schematic view of a packaging bag containing contents according to an embodiment of the present invention. FIG. 4 is a packaging bag 20 containing contents, which is formed by using the composite film of the present invention as a packaging material. FIG. 4A is a front view of the formed packaging bag 20 containing contents, and FIG. 4B is a back view.

The content-containing packaging bag 20 shown in FIG. 4 is made of a packaging material 30 made of a composite film. As shown in FIGS. 4 (a) and 4 (b), the heat-sealed layers themselves are heat-sealed at the upper and lower ends of the packaging material 30 to form a joint portion 31 of 10 mm, respectively.

Further, as shown in FIG. 4B, the ends of the packaging material 30 are heat-sealed in the vertical direction of the packaging bag 20 so as to connect the joint portion 31 at the upper end portion and the joint portion 31 at the lower end portion. The joint portion 31 is formed.

Then, when a part of the heat-sealed joint portion 31 is peeled off and opened, the aluminum layer and the heat-seal layer are broken at one or both of the outer end edge and the inner end edge of the heat-sealed joint portion 31. The adhesive layer is exposed because it is opened. This allows the exposed adhesive layer to reseal the packaging bag.

The packaging bag containing the contents formed from the composite film of the present invention is, for example, a package filled with non-heated foods such as snack candy and gummy candy as the contents, and when the contents are stored again after opening. In addition, it can be resealed without using rubber bands or clips. In addition, since it is possible to form a packaging bag that can be resealed without using a separate member such as a chuck tape, it is possible to provide a packaging body that is cost- and environmentally friendly, such as reducing the amount of resin material used and simplifying the work process. Can be done.

Further, in the resealable content-containing packaging bag formed by using the composite film of the present invention, the base material layer and the adhesive layer of the composite film are transparent, and the outer layer is more transparent than the aluminum layer. If so, the aluminum layer can be visually recognized from the base material layer side.

This makes it possible to confirm from the outside of the packaging bag that the aluminum layer has broken when the packaging bag is opened, and it is possible to determine whether the packaging bag is in an unopened state or in an opened and resealed state. It can be seen from the outside of the bag.

The present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

<Material>
In the examples and comparative examples, the following were prepared as the materials constituting the layer.

(1) Base material layer-Paper (NM Art, Nippon Paper Industries, Ltd., basis weight: 79.1 g / m ² )
-PET film (PETB, Unitika Ltd., thickness: 12 μm)
NY: Biaxially stretched nylon film (emblem (registered trademark) ON25, Unitika Ltd., thickness: 25 μm)

(2) Adhesive layer-SBBS / Polyterpen = 1: 1 (mass ratio) mixed resin SBBS (N515, Asahi Kasei Corporation)
Polyterpen (Sylvares® TRB115, Clayton)
SBBS / rosin ester = 1: 1 (mass ratio) mixed resin SBBS (N515, Asahi Kasei Corporation)
Rosin ester (ester gum (TM) AA-G, Arakawa Chemical Industry Co., Ltd.)
Amorphous polyester (Elitel (registered trademark) UE-3520-51EA, Unitika Ltd.)
Amorphous polyester / rosin ester = 9: 1 (mass ratio) mixed resin Amorphous polyester (Elitel® UE-3520-51EA, Unitika Ltd.)
Rosin Ester (Hari Tac (TM) 28JA, Harima Chemicals Group, Inc.)

(3) Aluminum layer-Aluminum foil (1N30, manufactured by UACJ Corporation, thickness: 7 μm)

(4) Heat seal layer-HDPE / LDPE = 7: 3 (mass ratio) mixed resin HDPE (Novatec (registered trademark) HD HJ490, Japan Polyethylene Corporation, density: 0.958 g / cm ³ )
LDPE (Suntech (registered trademark) LD L2340, Asahi Kasei Corporation, density: 0.923 g / cm ³ )
CPP # 30: Unstretched PP film (Pyrene (registered trademark) P1128, Toyobo Co., Ltd., thickness: 30 μm)

<< Example 1 >>
<Making a composite film>
A composite film having the stacking order shown in Table 1 was prepared. In Table 1, the portion bonded by the dry laminate is indicated by "//".

1. 1. The paper to be the first base material layer and the PET film to be the second base material layer were bonded together by dry laminating. As the dry laminating adhesive, a two-component curable dry laminating adhesive (Takelac A525 / Takenate A52, Mitsui Chemicals, Inc.) was used.

2. 2. A mixed resin of SBBS / polyterpene = 1: 1 (mass ratio), which is an adhesive layer, is applied to the PET film side so that the thickness of the adhesive layer is 4 μm, and an aluminum foil is applied via the adhesive layer. By dry laminating, a laminated body of (paper // PET film / adhesive layer / aluminum layer) was produced.

3. 3. A composite film is formed by extruding and laminating a mixed resin of HDPE / LDPE = 7: 3 (mass ratio), which is a heat-sealing layer, on the aluminum layer to a thickness of 5 μm via an adhesive. Obtained. As the adhesive, a two-component curable adhesive (Takelac A525 / Takenate A52, Mitsui Chemicals, Inc.) was used.

<Making lid material>
The obtained composite film was cut out in a diamond shape to prepare a lid material.

<Making a container with a lid>
The obtained lid material is heat-sealed in a PE-coated paper cup (flange width: 3 mm, opening inner diameter: 90 mm) using a heated heat-seal bar under the conditions of a heat-seal width of 3 mm, a pressure of 65 Mpa, and a time of 0.7 seconds. Then, a container with a lid was prepared.

<< Reference example 1 >>
<Making a composite film>
Each resin composition used for the resin layer (A), the adhesive resin layer (B), and the heat seal layer (C) as the base material layer is heated and melted by another extruder, and (A) / (B) / After laminating in the order of (C), a multilayer film was prepared by the T-die chill roll method.

<< Comparative Example 1 >>
<Making a composite film>
A composite film having the stacking order shown in Table 1 was prepared. In Table 1, the portion bonded by the dry laminate is indicated by "//".

1. 1. The PET film to be the second base material layer and the aluminum foil were bonded by dry laminating. As the dry laminating adhesive, a two-component curable dry laminating adhesive (Takelac A525 / Takenate A52, Mitsui Chemicals, Inc.) was used.

2. 2. A laminated body of (paper // aluminum layer // PET film) was produced by laminating paper to be the first base material layer on the aluminum foil side by dry laminating. As the dry laminating adhesive, a two-component curable dry laminating adhesive (Takelac A525 / Takenate A52, Mitsui Chemicals, Inc.) was used.

3. 3. A mixed resin of SBBS / polyterpene = 1: 1 (mass ratio), which is an adhesive layer, is applied to the PET film side so that the thickness of the adhesive layer is 4 μm, and the heat seal layer is passed through the adhesive layer. A composite resin was obtained by extruding and laminating the mixed resin of HDPE / LDPE = 7: 3 (mass ratio) so as to have a thickness of 5 μm.

<Making a lid material, making a container with a lid>
From the obtained composite film, a lid material was prepared in the same manner as in Example 1, and a container with a lid was prepared in the same manner as in Example 1.

Table 1 shows the configurations of the laminates produced in Example 1, Reference Example 1, and Comparative Example 1.

"evaluation"
(Initial interlayer strength)
The composite films obtained in Example 1 and Reference Example 1 were cut out into a rectangle having a width of 15 mm × 120 mm, and this was used as an evaluation sample.

The evaluation sample was heat-sealed on a polyethylene film under the conditions of a temperature of 150 ° C., a pressure of 3 kgf / cm ² , and a time of 1.5 seconds. Next, the heat-sealed sample was delaminated by the following method, and the initial delamination strength of the delaminated surface was measured. Delamination of the composite film produced in Example 1 occurred between the adhesive layer and the aluminum layer, and delamination of the composite film produced in Reference Example 1 occurred between the adhesive layer and the substrate layer.

In the measurement, using Strograph AGS-X (Shimadzu Corporation) as a measuring machine, the average peel strength at a peel length of 10 to 30 mm when peeling by 180 ° under the conditions of 200 mm / min and a peel length of 35 mm. Was calculated. The results are shown in Table 2.

The composite film produced in Example 1 could be opened with a smaller force than the composite film produced in Reference Example 1, while the initial interlayer strength was within the acceptable range.

(Confirmation of the location of delamination)
The containers with lids produced in Example 1 and Comparative Example 1 were initially opened, and the location of delamination was confirmed. The peeling location is shown in Table 3.

In the container with a lid produced in Comparative Example 1, delamination occurred between the PET-adhesive layers, whereas in the container with a lid produced in Example 1, delamination occurred between the adhesive layer and the aluminum layer. It could be confirmed.

(Relationship between the number of resealing and opening strength)
Regarding the containers with lids produced in Example 1 and Comparative Example 1, the relationship between the number of resealing and the opening strength was investigated. Regarding the sample that was initially opened, the adhesive layer and the Al layer were overlapped in the container with a lid prepared in Example 1, and the PET and the adhesive layer were overlapped in the container with a lid prepared in Comparative Example 1 to form a flange. The opening strength was measured when the film was peeled at 300 mm / min by 90 ° after being crimped again by acupressure for one round along the line. The results are shown in FIG.

(Evaluation of flange residue)
The containers with lids produced in Example 1 and Comparative Example 1 were evaluated for adhesive remaining on the flange at the time of initial opening. In the evaluation, the presence or absence of tack was confirmed by touching the flange after the initial opening with a finger (n = 10). The results are shown in Table 4.
〇: There was no tack ×: There was a tack

<< Example 2 >>
<Making a composite film>
Using the materials shown in Table 5, a composite film having a laminated structure of (base material layer / adhesive layer / aluminum layer // heat seal layer) was produced by the method shown below. The portion bonded by the dry laminate is indicated by "//". The composition (% by mass) of the pressure-sensitive adhesive layer indicates the amount of solid content of each component with respect to the entire pressure-sensitive adhesive layer.

1. 1. A mixed resin of SBBS / polyterpene = 1: 1 (mass ratio), which is an adhesive layer, is applied to a nylon film as a base material so that the dry weight is 3 g / m ² (thickness: 3 μm), and the adhesive is adhered. A laminated body of (nylon film / adhesive layer / aluminum layer) was produced by dry laminating an aluminum foil via a layer.

2. 2. A composite film was obtained by laminating a non-stretched PP film to be a heat seal layer on the aluminum layer via an adhesive. As the adhesive, a two-component curable adhesive (Takelac A525 / Takenate A52, Mitsui Chemicals, Inc.) was used.

<Making a packaging bag>
The obtained composite film was used as a packaging material to prepare a packaging bag shown in FIG. A rectangular packaging material having a length of 148 mm and a width of 200 mm was cut out from the composite film. Subsequently, as shown in FIG. 4 (b), the end portion 10 mm of the long piece of the packaging material is heat-sealed to form a tubular object, and finally, the upper end portion and the lower end portion are each heat-sealed by 10 mm. A packaging bag having a length of 148 mm and a width of 95 mm was produced.

The heat seal was carried out using FA-300-10W manufactured by Fuji Impulse Co., Ltd. under the conditions of a seal temperature of 200 ° C., a seal time of 1.0 second, and a cooling time of 2.0 seconds.

<< Examples 3 to 5 >>
A composite film was prepared in the same manner as in Example 2 except that the materials shown in Table 5 were used, and a packaging bag was prepared in the same manner as in Example 2.

"evaluation"
(Initial interlayer strength)
The composite film obtained in Examples 2 to 5 was cut out into a rectangle having a width of 15 mm × 120 mm, and this was used as an evaluation sample.

The evaluation sample was heat-sealed on a polyethylene film under the conditions of a temperature of 150 ° C., a pressure of 3 kgf / cm ² , and a time of 1.5 seconds. Next, the heat-sealed sample was delaminated by the following method, and the initial interlayer strength between the substrate layer and the aluminum layer was measured.

For the measurement, Strograph AGS-X (Shimadzu Corporation) was used as a measuring machine, and the average peel strength at a peel length of 10 to 30 mm when peeling by 180 ° under the conditions of 300 mm / min and a peel length of 35 mm. Was calculated. The measurement was carried out in a room temperature environment. The results are shown in Table 5.

(Resealing strength)
After measuring the above initial interlayer strength, the peeled portion was pressed with a finger to reattach. Then, the interlayer strength between the base material layer and the aluminum layer was measured by the same method as described above. The results are shown in Table 5.

(Confirmation of resealability)
The packaging bags prepared in Examples 2 to 5 were opened, and the opened portion was closed by acupressure. Subsequently, the same site was opened again, and the resistance at the time of resealing was evaluated according to the following evaluation criteria. The results are shown in Table 5.
〇: I feel resistance to my fingers when resealing.
×: No resistance is felt on the finger when resealing.

1 1st base material layer 2 2nd base material layer 3 Adhesive layer 4 Aluminum layer 5 Heat seal layer 10 Composite film 20 Packaging bag with contents 30 Packaging material 31 Joint part 100 Closure material 101 1st base material layer 102 1st 2 Base material layer 103 Adhesive layer 104 Aluminum layer 105 Heat seal layer 106 Resealing part 110 Tab 120a First break part 120b Second break part 200 Container body 202 Flange part 202a Joint part 250 Contents 300 With contents container

Claims (25)

The base material layer, the adhesive layer, the aluminum layer, and the heat seal layer are included in this order.
When the adhesive layer and the aluminum layer are adjacent to each other and the heat-sealed layers are heat-sealed and peeled off from each other, or when the heat-sealed layer and another material are heat-sealed and peeled off. At the edge of the heat-sealed portion, the aluminum layer and the heat-sealed layer are broken, and at the heat-sealed portion, delamination occurs between the adhesive layer and the aluminum layer.
Composite film. The composite film according to claim 1, wherein the adhesive layer contains a thermoplastic elastomer. The composite film according to claim 2, wherein the thermoplastic elastomer is a styrene-based thermoplastic elastomer. The composite film according to claim 2 or 3, wherein the thermoplastic elastomer is a styrene-butadiene-butylene-styrene copolymer. The composite film according to any one of claims 2 to 4, further comprising a polyterpene and / or a rosin ester. The composite film according to claim 1, wherein the adhesive layer contains an amorphous polyester. The composite film of claim 6, further comprising a polyterpene and / or a rosin ester. The composite film according to any one of claims 1 to 7, wherein the thickness of the adhesive layer is 5 μm or less. The composite film according to any one of claims 1 to 8, wherein the heat seal layer contains a polyolefin resin and has a thickness of 1 to 7 μm. The composite film according to any one of claims 1 to 9, wherein the heat seal layer is a polyethylene resin layer having a density of 0.920 to 0.958 g / cm ³ . The composite film according to claim 10, wherein the polyethylene resin layer contains high-density polyethylene and low-density polyethylene. The composite film according to claim 11, wherein the content of the high-density polyethylene is 50 to 90% by mass with respect to the total mass of the heat seal layer. A lid material formed from the composite film according to any one of claims 1 to 12. The lid material according to claim 13, which is for resealing. The lid material according to claim 13 or 14, wherein the adhesive layer and the aluminum layer are delaminated at the time of opening, and the adhesive layer is exposed in a resealable state with the aluminum layer. The lid material according to any one of claims 13 to 15, which does not have a half cut on the heat seal layer side. A container body with a storage part and a flange part,
The contents contained in the container body and
A lid material formed from the composite film according to any one of claims 1 to 12 is provided.
The heat seal layer is heat sealed to the flange portion to form a resealable joint.
A container with a lid containing the contents. The container with a lid containing the contents according to claim 17, wherein at the time of opening, the adhesive layer and the aluminum layer at the joint portion are delaminated and the aluminum layer is exposed to the flange portion in a resealable state. .. The container body is a paper cup and
The container with a lid containing the contents according to claim 17 or 18, wherein the flange portion has a coating made of a polyethylene resin. The lid material according to any one of claims 13 to 16, wherein the base material layer and the adhesive layer are transparent, whereby the aluminum layer can be visually recognized from the base material layer side, or claim 17. A container with a lid containing the contents according to any one of 19 to 19. A packaging bag formed by heat-sealing at least a part of the heat-sealing layer of the composite film according to any one of claims 1 to 12. The packaging bag according to claim 21, wherein the adhesive layer and the aluminum layer are delaminated at the time of opening, and the adhesive layer is exposed in a resealable state with the aluminum layer. The packaging bag according to claim 21 or 22, which does not have a half cut on the heat seal layer side. The packaging bag according to any one of claims 21 to 23, and a packaging bag containing the contents having the contents contained in the packaging bag. The packaging bag according to any one of claims 21 to 23, or claim 24, wherein the base material layer and the adhesive layer are transparent so that the aluminum layer can be visually recognized from the base material layer side. Packaging bag with the contents described in.

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