WO2014024602A1 - Packaging material to be thermally welded to package - Google Patents

Abstract

A packaging material to be thermally welded to a package, which is characterized by comprising a gas barrier film (12), an intermediate layer (16) that is bonded to the gas barrier film by means of a first adhesive layer (14), and a thermal welding layer (20) that is bonded to the intermediate layer by means of a second adhesive layer (18). This packaging material is also characterized in that: the gas barrier film has a laminated structure wherein one or more combinations of one inorganic layer (28) that has gas barrier properties and one organic layer (26) that serves as a base layer for the inorganic layer are formed on a supporting body (24) so that an organic layer (26) forms the outermost layer; the glass transition temperature of the organic layer is higher than the glass transition temperatures of the intermediate layer and the supporting body of the gas barrier film; and the glass transition temperatures of the intermediate layer and the supporting body of the gas barrier film are higher than the glass transition temperature of the thermal welding layer.

Description

[Name of invention determined by ISA based on Rule 37.2] Packaging material thermally welded to packaging material

The present invention relates to a packaging material that is thermally welded to a packaging material such as a medical infusion bag or a tube for food, and more specifically, imparts a high gas barrier property to the packaging material by being thermally welded to the packaging material. It relates to packaging materials.

Infusion bags that contain drugs that are altered by moisture and oxygen, and tubes and packaging bags that contain foods that are also deteriorated by moisture and oxygen are required to have high gas barrier properties.
There is also known an infusion bag in which water is stored in one of two chambers separated by a partition wall, a drug is stored in the other, and the partition wall is opened immediately before use to mix water and the drug. In such an infusion bag, in order to perform an appropriate treatment, it is important that water and a medicine are reliably mixed, and it is preferable that it can be visually confirmed. Thus, in a packaging container that requires confirmation of the contents, it is also required to ensure the internal visibility.

Various proposals have been made to meet such demands.
For example, in Patent Document 1, a gas barrier film (gas barrier film) comprising two films having a predetermined adhesive region on the periphery and having an oxygen-blocking metal layer is bonded to the adhesive region of at least one film. A package is described.
When the package is not used, oxygen is blocked by the gas barrier film to prevent the contents from being deteriorated. When the package is used, the gas barrier film is peeled off from the periphery to ensure visibility inside the package.

Further, in Patent Document 2, in a container having a plurality of two chambers communicated with each other by breakage of a partition wall, a product which is easily deteriorated by oxygen is accommodated in one chamber, and this chamber is used as a gas barrier film (gas barrier exterior film). And a container in which an oxygen-absorbing resin layer is provided inside the exterior film.
Patent Document 3 discloses a gas barrier film (a cover sheet impermeable to moisture and oxygen) that can be peeled to a powder storage chamber in a container having a powder storage chamber and a liquid storage chamber communicated by breakage of a partition wall. It is described that the powder is adhered and the powder is protected with a gas barrier film.

Furthermore, Patent Document 4 discloses an inner layer composed of a first resin layer and a second resin layer formed of a polyethylene resin satisfying a predetermined relationship between a melting point, a density, and a melt flow rate, a nylon layer, and PET ( In laminated film for laminated tube to which an ultrasonic seal having an intermediate layer and an outer layer formed of a polyethylene-based resin is applied from a polyethylene terephthalate) layer, if necessary, a gas barrier film (between the outer layer and the intermediate layer) It is described that a gas barrier property is imparted to the laminated film by providing a barrier substrate layer).

By the way, as a gas barrier film having very high gas barrier properties, an organic / inorganic laminated type (hereinafter also simply referred to as “laminated type”) gas barrier film in which an organic layer and an inorganic layer are laminated is known.
The laminated gas barrier film is a PET film or the like as a support, an organic layer serving as a base layer is formed on the surface of the support, and an inorganic layer such as silicon nitride that exhibits gas barrier properties is formed on the organic layer. It has the structure which formed into a film. In addition, an organic layer for protecting the inorganic layer may be provided on the inorganic layer.

In a laminated gas barrier film, an appropriate inorganic layer free from cracks and cracks can be formed on the entire surface of the film by having an underlying organic layer. Thereby, the gas barrier film which fully exhibited the high gas barrier property which an inorganic layer has, and has high gas barrier property can be obtained.
In addition, by having an organic layer as the uppermost layer, it is possible to prevent cracks and cracks from occurring in the hard and brittle inorganic layer, and to stably obtain high gas barrier properties.

It is also known to use such a laminated gas barrier film for a packaging container.
For example, Patent Document 5 describes an infusion bag in which a barrier layer having a first organic layer, an inorganic layer, and a second organic layer is provided on a resin bag containing polyethylene and / or polypropylene.
The barrier layer is basically configured by using a plastic film as a support and laminating a first organic layer, an inorganic layer, and a second organic layer on the support.

JP-A-10-277135 Japanese Patent Laid-Open No. 10-201818 Japanese Patent Laid-Open No. 2003-230618 International Publication No. 2003-099557 JP 2012-75716 A

As described above, the laminated gas barrier film has excellent gas barrier properties.
Therefore, by using a laminated gas barrier film as shown in Patent Document 5 for medical infusion bags and food tubes as shown in Patent Documents 1 to 4, gas barrier properties can be further improved. It can be expected that an excellent packaging container will be obtained.

Here, as shown in Patent Document 5, when a laminated gas barrier film is used for a packaging container, the surface of the gas barrier film (opposite to the plastic film serving as a support) is coated with an adhesive from the plastic film. It is conceivable that a heat-welding layer is attached and the heat-welding layer and the packaging container are heat-welded (heat sealing (heat sealing)).
However, according to the study of the present inventor, when a laminated gas barrier film is thermally welded to a packaging container, there are many cases where the excellent gas barrier property of the laminated gas barrier film cannot be obtained.

An object of the present invention is to solve the above-mentioned problems of the prior art, such as organic / inorganic laminated gas barrier films having excellent gas barrier performance, medical infusion bags, food tubes, packaging bags, etc. To provide a packaging material capable of exerting excellent gas barrier properties of an organic / inorganic laminated gas barrier film by being thermally welded to the packaging materials, and imparting excellent gas barrier properties to these packaging materials. It is in.

In order to solve the above problems, the packaging material of the present invention is a packaging material thermally welded to a packaging material,
A gas barrier film, an intermediate layer bonded to the gas barrier film by the first adhesive layer, and a heat welding layer bonded to the intermediate layer by the second adhesive layer;
The gas barrier film has a laminated structure in which one or more combinations of an inorganic layer having gas barrier properties and an organic layer serving as a base layer of the inorganic layer are formed on a support, and the uppermost layer is an organic layer. And
Further, a packaging material characterized in that the glass transition temperature of the organic layer is higher than that of the support of the intermediate layer and the gas barrier film, and the glass transition temperature of the support of the intermediate layer and the gas barrier film is higher than that of the heat-welded layer. provide.

In such a packaging material of the present invention, the thickness from the first adhesive layer to the heat-welded layer is preferably 100 μm or less.
Moreover, it is preferable that an intermediate | middle layer and the support body of a gas barrier film are formed with the same material.
Moreover, it is preferable that all the organic layers are formed with the same material.
Moreover, it is preferable that the thickness of a heat welding layer is 60 micrometers or less.
Moreover, it is preferable that the thickness of an intermediate | middle layer is 20 micrometers or less.
Moreover, it is preferable that an organic layer is a layer which consists of at least one of an acrylic resin and a methacryl resin.
The inorganic layer is preferably a layer made of silicon nitride.
Moreover, it is preferable that a heat welding layer is a layer which consists of polyethylene or a polypropylene.
Further, the intermediate layer is preferably a layer made of polyethylene terephthalate.

The packaging material of the present invention having the above-described structure has excellent gas barrier properties possessed by an organic / inorganic laminate type gas barrier film by heat-welding to packaging materials such as medical infusion bags, food tubes and packaging bags. , And can be applied to these packaging material bags.

It is a figure which shows notionally an example of the packaging material of this invention. It is a figure which shows notionally an example of the gas barrier film utilized for the packaging material of this invention.

Hereinafter, the packaging material of the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

FIG. 1 conceptually shows an example of the packaging material of the present invention.
The packaging material 10 shown in FIG. 1 basically includes a gas barrier film 12, a first adhesive layer 14, an intermediate layer 16, a second adhesive layer 18, and a heat welding layer 20. The
In the present invention, the gas barrier film 12 has a combination of an inorganic layer 28 that exhibits gas barrier properties on the support 24 and an organic layer 26 that serves as a base layer (undercoat layer) of the inorganic layer 28. This is an organic / inorganic laminated type (hereinafter also simply referred to as “laminated type”) gas barrier film having one or more layers formed, and an organic layer 26 as a protective layer formed on the uppermost layer (surface).

In the illustrated packaging material 10, the gas barrier film 12 has an organic layer 26 on a support 24, an inorganic layer 28 on the organic layer 26, and an organic layer 26 on the organic layer 26. A three-layer structure having three layers.
That is, in the gas barrier film 12, the organic layer 26 on the support 24 is a base layer for the inorganic layer 28, and the organic layer 26 on the inorganic layer 28 is a protective layer for protecting the inorganic layer 28.

Such a packaging material 10 of the present invention is thermally welded to a medical infusion bag, a food tube, a packaging bag, or the like, so that, for example, a water vapor permeability of 1 × 10 ⁻⁴ [g / (m ² · day)], such as high gas barrier properties.
In the packaging material of the present invention, the packaging material to be thermally welded is not limited to the above-mentioned infusion bag, food tube or packaging bag. That is, the packaging material of the present invention is a bag that contains non-medical liquids such as drugs, tubes and packaging bags (housing bags) that contain articles other than food, and sheet materials for packaging such as packaging films, Various packaging materials that wrap or contain various articles, especially articles that deteriorate due to moisture, oxygen, etc., such as casings (cases) and packages that contain articles (hereinafter collectively referred to as “packaging materials”) Is available.

In the packaging material of the present invention, the gas barrier film is not limited to a three-layer structure as shown in FIG. That is, in order to obtain a higher gas barrier property, a plurality of combinations of the inorganic layer 28 and the organic layer 26 serving as a base layer of the inorganic layer 28 may be provided.
As an example, as shown in FIG. 2, an organic layer 26 as an underlayer is provided on a support 24, an inorganic layer 28 is provided thereon, and an organic layer 26 as an underlayer is provided thereon. Further, it may be a gas barrier film having a five-layer structure in which an inorganic layer 28 is provided thereon and an organic layer 26 is provided as a protective layer on the uppermost layer. That is, the gas barrier film shown in FIG. 2 has two combinations of the inorganic layer 28 and the underlying organic layer 26.
Further, in order to obtain a higher gas barrier property, a gas barrier film having three or more combinations of the inorganic layer 28 and the underlying organic layer 26 may be used.

In the packaging material 10 of the present invention, the gas barrier film 12 is formed by alternately laminating organic layers 26 and inorganic layers 28 on a support 24.
In such a gas barrier film 12, the support 24 is not limited, and is not limited to a laminated gas barrier film. Various known sheet-like materials that are used as supports for various gas barrier films can be used. Is possible.

Specifically, as the support 24 (substrate (base material)), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethylene, polypropylene, polystyrene, polyamide, polyvinyl chloride, polycarbonate, polyacrylonitrile, polyimide, Preferable examples include plastic films made of various plastics (polymer materials) such as polyacrylate and polymethacrylate.
In the present invention, various functions such as a protective layer, an adhesive layer, a light reflection layer, an antireflection layer, a light shielding layer, a planarization layer, a buffer layer, and a stress relaxation layer are provided on the surface of such a plastic film. What is formed with a layer (film) for obtaining may be used as the support 24.

As will be described in detail later, in the packaging material of the present invention, the support 24 has a glass transition temperature (glass transition point Tg) lower than that of the organic layer 26 and higher than that of the heat welding layer 20.
Here, the glass transition temperature of the intermediate layer 16 described later is also lower than the organic layer 26 and higher than the heat-welded layer 20. Further, the glass transition temperature of the support 24 is preferably the same as or substantially the same as that of the intermediate layer 16. In particular, the support 24 and the intermediate layer 16 are preferably formed of the same material.

In the gas barrier film 12, as described above, the organic layer 26 as the base layer of the inorganic layer 28 is provided on the support 24. Furthermore, the uppermost layer of the gas barrier film 12 has an organic layer 26 as a protective layer.
The organic layer 26 is a layer made of an organic compound (a layer (film) containing an organic compound as a main component) and is basically a crosslinked (polymerized) monomer and / or oligomer.

The organic layer 26 on the support 24 functions as a base layer for properly forming the inorganic layer 28 exhibiting gas barrier properties.
By having such an organic layer 26 as a base, the surface of the support 24 is embedded, the foreign matter adhering to the surface of the support 24 is embedded, and the film-forming surface of the inorganic layer 28 is made inorganic. A state suitable for forming the layer 28 can be obtained. This eliminates regions where the inorganic compound that becomes the inorganic layer 28 is difficult to deposit, such as irregularities on the surface of the support 24 and shadows of foreign matter, and forms an appropriate inorganic layer 28 on the entire surface of the substrate without any gaps. It becomes possible to film.

The uppermost organic layer 26 is a protective layer that protects the inorganic layer 28.
The inorganic layer 28 is a layer made of an inorganic compound such as silicon nitride, and is hard and brittle. For this reason, damage such as cracks and cracks can easily occur due to contact with other members or receiving some kind of impact.
The inorganic layer 28 exhibits mainly gas barrier properties in the gas barrier film 12. Therefore, when the inorganic layer 28 is damaged, moisture, oxygen, and the like can be transmitted from the damaged portion, and the gas barrier property is greatly lowered.
On the other hand, by having the organic layer 26 acting as a protective layer as the uppermost layer, damage to the inorganic layer 28 due to contact or impact can be prevented.

That is, in the (organic / inorganic) laminated gas barrier film 12 used in the packaging material 10 of the present invention, the organic layer 26 serving as a base layer of the inorganic layer 28 and the organic layer 26 serving as a protective layer of the inorganic layer 28 are provided. By having it, an appropriate inorganic layer 28 can be formed on the entire surface without any gap, and damage to the inorganic layer 28 can be prevented.
Therefore, the laminated gas barrier film 12 exhibits the excellent gas barrier properties of the inorganic layer 28, for example, high gas barrier properties such that the water vapor permeability is less than 1 × 10 ⁻⁴ [g / (m ² · day)]. A high-performance gas barrier film having the above can be obtained stably.

In the gas barrier film 12 used for the packaging material 10 of the present invention, the material for forming the organic layer 26 is not limited, and various known organic compounds (resins / polymer compounds) can be used.
Specifically, polyester, acrylic resin, methacrylic resin, methacrylic acid-maleic acid copolymer, polystyrene, transparent fluororesin, polyimide, fluorinated polyimide, polyamide, polyamideimide, polyetherimide, cellulose acylate, polyurethane, poly Ether ether ketone, polycarbonate, alicyclic polyolefin, polyarylate, polyether sulfone, polysulfone, fluorene ring modified polycarbonate, alicyclic modified polycarbonate, fluorene ring modified polyester, acryloyl compound, thermoplastic resin, or polysiloxane, etc. An organic silicon compound film is preferably exemplified. A plurality of these may be used in combination.

Among these, the organic layer 26 composed of a polymer of a radical polymerizable compound and / or a cationic polymerizable compound having an ether group as a functional group is preferable in terms of excellent glass transition temperature and strength.
In particular, in addition to the above glass transition temperature and strength, acrylic resins mainly composed of acrylate and / or methacrylate monomers and oligomers in terms of low refractive index, high transparency and excellent optical properties, etc. The methacrylic resin is preferably exemplified as the organic layer 26.
Among them, in particular, dipropylene glycol di (meth) acrylate (DPGDA), trimethylolpropane tri (meth) acrylate (TMPTA), dipentaerythritol hexa (meth) acrylate (DPHA), etc. Acrylic resins and methacrylic resins mainly composed of a polymer of acrylate and / or methacrylate monomers or oligomers are preferably exemplified. It is also preferable to use a plurality of these acrylic resins and methacrylic resins.

Here, as will be described in detail later, in the packaging material 10 of the present invention, the glass transition temperature of the organic layer 26 is higher than that of the support 24 and the intermediate layer 16. Specifically, the glass transition temperature of the organic layer 26 is preferably 70 ° C. or more higher than the glass transition temperatures of the support 24 and the intermediate layer 16. Further, as described above, the glass transition temperature of the support 24 and the intermediate layer 16 is higher than that of the heat welding layer 20. Specifically, the glass transition temperature of the support 24 and the intermediate layer 16 is preferably 70 ° C. or more higher than the glass transition temperature of the heat welding layer 20. Therefore, in the packaging material 10, the glass transition temperature of each layer excluding the adhesive layer (the glass transition temperature of the material forming each layer) is
Thermal weld layer 20 <support 24 and intermediate layer 16 <organic layer 26
It becomes. That is, in the packaging material 10 of the present invention, with the inorganic layer 28 as the center (from the outermost organic layer 26 when there are a plurality of organic layer / inorganic layer repetitions), as each layer goes outward, The glass transition temperature is lowered.
In addition, naturally the glass transition temperature of the organic layer 26 is lower than the inorganic layer 28 which is a layer which consists of an inorganic compound.

The packaging material 10 of the present invention is thermally welded (thermally fused) to a packaging material such as an infusion bag or a food packaging bag by the heat welding layer 20.
As described above, the packaging material 10 of the present invention has a configuration in which the glass transition temperature of each layer decreases as it goes outward with the inorganic layer 28 as the center. It is possible to prevent the inorganic layer 28 from being damaged by being softened and deformed by heat, and to stably exhibit the target gas barrier property.
The above points will be described in detail later.

The thickness of the organic layer 26 is not limited, but is preferably 0.5 to 5 μm.
By setting the thickness of the organic layer 26 to 0.5 μm or more, irregularities on the surface of the support 24 and foreign matters attached to the surface of the support 24 are suitably embedded, so that the surface of the organic layer 26, that is, the inorganic layer The film-forming surface 28 can be flattened.
Further, by setting the thickness of the organic layer 26 to 5 μm or less, it is possible to suitably suppress the occurrence of problems such as cracks in the organic layer 26 and curling of the gas barrier film 12 caused by the organic layer 26 being too thick. be able to.
Considering the above points, the thickness of the organic layer 26 is more preferably 1 to 3 μm.

In addition, in this invention, although the gas barrier film 12 has the some organic layer 26, the thickness of each organic layer 26 may be the same, or may mutually differ.
The material for forming each organic layer 26 may be the same or different. However, in the packaging material 10 of the present invention, it is preferable that all the organic layers 26 are formed of the same material from the viewpoint of preventing damage to the inorganic layer 28 described later and productivity.

Such an organic layer 26 may be formed (formed) by a known method.
For example, a coating material containing an organic solvent, an organic compound that becomes the organic layer 26, a surfactant, and the like is prepared, and this coating material is applied, dried, and then crosslinked to form a film by a so-called coating method.

The inorganic layer 28 is a layer made of an inorganic compound (a layer (film) containing an inorganic compound as a main component).
In the gas barrier film 12 used for the packaging material 10 of the present invention, the inorganic layer 28 mainly exhibits the target gas barrier property.

The material for forming the inorganic layer 28 is not limited, and various layers made of an inorganic compound that exhibits gas barrier properties can be used.
Specifically, metal oxides such as aluminum oxide, magnesium oxide, tantalum oxide, zirconium oxide, titanium oxide, and indium tin oxide (ITO); metal nitrides such as aluminum nitride; metal carbides such as aluminum carbide; silicon oxide, Silicon oxides such as silicon oxynitride, silicon oxycarbide, silicon oxynitride carbide; silicon nitrides such as silicon nitride and silicon nitride carbide; silicon carbides such as silicon carbide; hydrides thereof; mixtures of two or more of these; and Films made of inorganic compounds such as these hydrogen-containing materials are preferably exemplified.
In particular, silicon nitride, silicon oxide, silicon oxynitride, and aluminum oxide are suitably used for the gas barrier film because they are highly transparent and can exhibit excellent gas barrier properties. Of these, silicon nitride is particularly suitable for its excellent gas barrier properties and high transparency.

In the present invention, the thickness of the inorganic layer 28 is not limited. That is, the thickness of the inorganic layer 28 may be determined as appropriate according to the forming material so that the target gas barrier property can be exhibited. According to the study of the present inventor, the thickness of the inorganic layer 28 is preferably 10 to 200 nm.
By setting the thickness of the inorganic layer 28 to 10 nm or more, the inorganic layer 28 that stably exhibits sufficient gas barrier performance can be formed. In addition, the inorganic layer 28 is generally fragile, and if it is too thick, there is a possibility of causing cracks, cracks, peeling, etc. However, if the thickness of the inorganic layer 28 is 200 nm or less, cracks will occur. Can be prevented.
In consideration of such points, the thickness of the inorganic layer 28 is preferably 15 to 100 nm, and particularly preferably 20 to 75 nm.
Moreover, when the gas barrier film has a plurality of inorganic layers 28 as in the example shown in FIG. 2, the thickness of each inorganic layer 28 may be the same or different.

In the present invention, when the gas barrier film 12 has a plurality of inorganic layers 28, the thickness of each inorganic layer 28 may be the same or different from each other.
Moreover, when the gas barrier film 12 has the some inorganic layer 28, the formation material of each inorganic layer 28 may be the same, or may differ.

In the packaging material 10 (gas barrier film 12) of the present invention, the method for forming the inorganic layer 28 is not limited, and depending on the inorganic layer 28 to be formed, a known method for forming an inorganic layer (inorganic film) is used. Various types are available.
Specifically, plasma CVD such as CCP-CVD and ICP-CVD, sputtering such as magnetron sputtering and reactive sputtering, and vapor phase film forming methods such as vacuum deposition are preferably exemplified.

In the packaging material 10 of the present invention, the intermediate layer 16 is bonded onto the gas barrier film 12 by the first adhesive layer 14.
The intermediate layer 16 is a layer for preventing the inorganic layer 28 from being damaged when the packaging material 10 of the present invention is thermally welded to a packaging material such as an infusion bag.
As described above, in the packaging material 10 of the present invention, the intermediate layer 16 has a glass transition temperature lower than that of the organic layer 26 and higher than that of the heat-welded layer 20, similarly to the support 24. Furthermore, the glass transition temperature of the intermediate layer 16 is preferably the same as or substantially the same as that of the support 24, and it is more preferable that the intermediate layer 16 and the support 24 are formed of the same material.
The intermediate layer 16 will be described later in detail.

Further, in the packaging material 10 of the present invention, the heat welding layer 20 is bonded onto the intermediate layer 16 by the second adhesive layer 18.
As described above, the packaging material 10 of the present invention is heat-welded (heat sealed / heat sealed) to the surface of the packaging material. The heat welding layer 20 is a layer (sealant layer) for performing this heat welding.
Therefore, the heat welding layer 20 is basically formed of the same material as a forming material (forming material on the surface of the packaging material) of a packaging material such as an infusion bag to which the packaging material 10 of the present invention is thermally welded. That is, when the packaging material is made of polyethylene (PE), a PE sheet-like material (film-like material) may be used as the heat welding layer 20, and when the packaging material is made of polypropylene (PP). In this case, a PP sheet-like material may be used as the heat welding layer 20.

In the packaging material 10 of the present invention, the gas barrier film 12 has an organic layer 26 as a base layer of the inorganic layer 28 exhibiting gas barrier properties, and has an organic layer 26 as a protective layer of the inorganic layer 28 in the uppermost layer. It is a laminated gas barrier film. The laminated gas barrier film 12 has a very high gas barrier property, for example, a high gas barrier property such that the water vapor permeability is less than 1 × 10 ⁻⁴ [g / (m ² · day)].
Therefore, by using this laminated gas barrier film 12 for packaging materials such as infusion bags and food packaging bags, it is possible to obtain packaging materials with high gas barrier properties, and to prevent deterioration of drugs and foods due to moisture and oxygen. It can be prevented greatly.

Here, as shown in Patent Document 5, when the laminated gas barrier film 12 is used as a packaging material, a sheet-like material (film) made of the same material as the packaging material is formed on the surface of the uppermost organic layer 26. The gas barrier film 12 and the packaging material are laminated in a state where they are bonded with an adhesive as a heat welding layer and in contact with the heat welding layer, and heated while pressing from the support 24 side of the gas barrier film 12. A method of thermally welding the surface and the heat welding layer is conceivable.
However, according to the study of the present inventor, when the laminated gas barrier film 12 is simply thermally welded to the packaging material by such a method, there are many cases where the excellent gas barrier property of the gas barrier film 12 cannot be obtained. Arise.

As a result of intensive studies, the present inventor has found that the cause of the decrease in gas barrier properties is due to deformation (contraction / expansion) of the heat-welded layer by heating.
Specifically, when the packaging material and the gas barrier film 12 are thermally welded, the heat-welded layer is deformed, so that the inorganic layer 28 of the gas barrier film 12 is damaged due to the deformation force. It has been found that the gas barrier properties of the film 12 are greatly reduced.

The gas barrier film 12 has an organic layer 26 as the uppermost layer.
By having the uppermost organic layer 26, it is possible to prevent the inorganic layer 28 mainly exhibiting the gas barrier property from being damaged during the handling of the gas barrier film 12 and the process of using the gas barrier film 12.
That is, the gas barrier film 12 has the uppermost organic layer 26, so that the gas barrier film 12 has a high gas barrier performance such that the water vapor transmission rate is less than 1 × 10 ⁻⁴ [g / (m ² · day)]. Can be demonstrated.
In other words, in a gas barrier film that does not have the uppermost organic layer 26, damage such as cracks and cracks occurs in the inorganic layer 28 during use and the like, and moisture and gas pass through the damaged portion, greatly improving gas barrier properties. It will drop to. That is, it is difficult to secure the high gas barrier property as described above with a gas barrier film that does not have the uppermost organic layer 26.

Here, according to the study of the present inventor, when the (organic / inorganic) laminated gas barrier film 12 is thermally welded to the packaging material, the uppermost organic layer 26 has a high glass transition temperature to some extent. It is preferable to have.
In particular, the uppermost organic layer 26 preferably has a glass transition temperature of 120 ° C. or higher.

That is, as described above, the heat-welded layer for heat-welding with the packaging material is bonded to the uppermost organic layer 26 by the adhesive layer. Here, if the glass transition temperature of the uppermost organic layer 26 is low, the adhesive layer is softened by heat at the time of drying the solvent of the adhesive layer, and the function as a protective layer for the inorganic layer 28 is not achieved.
Moreover, when heat-welding a heat welding layer and a packaging material, it is necessary to heat and pressurize to high temperature. In particular, in consideration of productivity, in order to perform heat welding in a short time, it is preferable to perform heating at a temperature much higher than the melting temperature of the heat welding layer. At this time, if the glass transition temperature of the uppermost organic layer 26 is low, the organic layer 26 expands due to heat between the heat-welded layer and the inorganic layer 28 and presses both layers, and thus the inorganic layer 28 will be damaged.
Furthermore, in the laminated gas barrier film 12, the inorganic layer 28 is usually formed by plasma CVD, sputtering, or the like. For this reason, the organic layer 26 that is the underlayer of the inorganic layer 28 is required to have plasma resistance, and preferably has a glass transition temperature that is somewhat high. Here, the gas barrier film 12 has a plurality of organic layers 26. In consideration of productivity, it is preferable to form all the organic layers 26 with the same material. Therefore, it is preferable that the uppermost organic layer 26 also has a high glass transition temperature to some extent.

As described above, when the laminated gas barrier film 12 is heat-welded to the packaging material, it is preferable to adhere the heat-welding layer to the organic layer 26 having a somewhat high glass transition temperature.
Here, in consideration of productivity, in order to enable thermal welding in a short time, the thermal welding layer is preferably melted at a low temperature.
At the time of heat welding, the heat welding layer is deformed. However, the organic layer 26 having a high glass transition temperature is strong against heat, but is hard and thus weak against stress. Further, the heat-welded layer and the organic layer 26 are strongly bonded with an adhesive. For this reason, the organic layer 26 is also deformed and further damaged by the deformation of the heat-welded layer.

This deformation and damage of the organic layer 26 is also transmitted to the adjacent and strongly adhered inorganic layer 28. The inorganic layer 28 is made of an inorganic compound such as silicon nitride, has a glass transition temperature higher than that of the organic layer 26, and is harder and more brittle.
As a result, the inorganic layer 28 to which the deformation and destruction of the organic layer 26 are transmitted is subjected to an excessive force to be deformed, and the inorganic layer 28 is damaged such as cracks and cracks.
If the inorganic layer 28 is damaged, moisture and oxygen can permeate from here, so that the gas barrier property is lowered. In particular, the laminated gas barrier film 12 has a high gas barrier property such that the water vapor transmission rate is less than 1 × 10 ⁻⁴ [g / (m ² · day)], so even if the inorganic layer 28 is slightly damaged. , Will be a very big performance degradation.

On the other hand, the packaging material 10 of the present invention has an intermediate layer 16 between the heat welding layer 20 and the gas barrier film 12. Further, the glass transition temperature of the intermediate layer 16 and the support 24 of the gas barrier film 12 is lower than that of the organic layer 26 and higher than that of the heat welding layer 20.
Therefore, the glass transition temperature of each layer (each layer excluding the adhesive layer) constituting the packaging material 10 is:
Thermal weld layer 20 <support 24 and intermediate layer 16 <organic layer 26
It becomes. That is, in the packaging material 10 of the present invention, the glass transition temperature of each layer decreases as it goes outward with the inorganic layer 28 as the center. In other words, in the packaging material 10 of the present invention, the softening property due to heating of each layer increases as it goes outward with the inorganic layer 28 as the center.
Since the packaging material 10 of the present invention has such a configuration, it is possible to appropriately perform the thermal welding with the packaging material, and the thermal welding layer 20 (the uppermost organic layer 26) at the time of the thermal welding. Even if deformed, damage to the inorganic layer 28 can be prevented.

That is, the intermediate layer 16 has a glass transition temperature higher than that of the heat welding layer 20 and lower than that of the organic layer 26 between the heat welding layer 20 and the organic layer 26. Therefore, when the packaging material 10 is heat-welded with the packaging material, even if the heat-welded layer 20 is largely deformed by heating, the intermediate layer 16 functions as a buffer layer that buffers deformation of the heat-welded layer 20. As a result, the deformation and force of the heat welding layer 20 transmitted from the heat welding layer 20 to the organic layer 26 can be greatly reduced. Moreover, since the organic layer 26 has a glass transition temperature higher than that of the intermediate layer 16, the deformation and force of the heat-welded layer 20 transmitted from the organic layer 26 to the inorganic layer 28 can be greatly reduced.
Therefore, even if the shrinkage of the heat-welded layer 20 is transmitted to the inorganic layer 28, the amount of deformation transmitted is small and the force is weak, so that the inorganic layer 28 can be prevented from being damaged such as cracks and cracks.
Furthermore, since the heat welding layer 20 has the lowest glass transition temperature, layers other than the heat welding layer 20 can be prevented from being damaged by heat when the packaging material 10 is heat welded to the packaging material.

In the packaging material of the present invention, not only the intermediate layer 16 but also the support 24 of the gas barrier film 12 has a glass transition temperature lower than that of the organic layer 26 and higher than that of the heat-welded layer 20. That is, the intermediate layer 16 and the support 24 have the same glass transition temperature in each layer constituting the packaging material 10.
The thermal welding of the packaging material 10 is usually performed by closely contacting the thermal welding layer 20 to the packaging material and heating the support 24. At this time, if the glass transition temperature of the intermediate layer 16 is significantly higher than that of the support 24, the intermediate layer 16 is in a direction to suppress the deformation with respect to the deformation of the gas barrier film 12 during the thermal welding. work. That is, the intermediate layer 16 holds the uppermost organic layer 26 and inorganic layer 28. As a result, the underlying organic layer 26 and the inorganic layer 28 cannot follow the deformation of the support 24, and the inorganic layer 28 is still damaged.
On the other hand, since the intermediate layer 16 and the support 24 have the same glass transition temperature, the intermediate layer 16 is also deformed in the same manner as the support. Damage can be prevented.

Considering the above points, the glass transition temperatures of the intermediate layer 16 and the support 24 are preferably the same or substantially the same.
In particular, when the support 24 is PET, it is more preferable to form the intermediate layer 16 and the support 24 with the same material, such as forming the intermediate layer 16 with the same PET.

Here, there is also an idea that the support 24 and the organic layer 26 serving as a base are both formed of a material having an equally high glass transition temperature to prevent deformation of the support 24 at the time of heat welding.
However, the glass transition temperature that can sufficiently exhibit the plasma resistance required for the organic layer 26 as a base and that can completely suppress expansion during welding is about 200 ° C. A plastic film having such a high glass transition temperature and transparency is limited to transparent polyimide or the like and becomes very expensive. Therefore, this selection is not realistic.

The problem of damage to the inorganic layer 28 due to the deformation of the heat-welded layer 20 during this heat-welding is that the uppermost layer is the organic layer 26 and the water vapor transmission rate is 1 × 10 ⁻⁴ [g / (m ^This is a problem peculiar to the laminated gas barrier film 12 having a high gas barrier property such as less than ² · day).

A gas barrier film formed by directly forming an inorganic layer 28 on a support as shown in Patent Document 4 is basically a high gas barrier such as a laminated gas barrier film 12 whose surface is an organic layer 26. Does not have sex.
On the other hand, as described above, since the surface of the laminated gas barrier film having the organic layer 26 as the base layer but not having the organic layer 26 as the protective layer is the inorganic layer 28, When performing various treatments, it is difficult to avoid damage to the inorganic layer 28. Therefore, as a result, this gas barrier film also does not have a high gas barrier property like the laminated gas barrier film 12 whose surface is the organic layer 26 fundamentally.

Therefore, in these gas barrier films, even if the inorganic layer 28 is somewhat damaged due to deformation of the heat-welded layer, the gas barrier property is hardly lowered and does not cause a problem in performance. That is, in a packaging material in which a heat-welding layer is provided on the surface of these gas barrier films, performance degradation due to deformation of the heat-welding layer hardly occurs and does not cause a problem. Therefore, in these gas barrier films, even if the intermediate layer 16 as in the present invention is provided in the lower layer of the heat welding layer 20, it is meaningless, one extra layer is added, and the cost is increased. Only the heat weldability to the packaging material is reduced.
On the other hand, in the laminated gas barrier film 12, the uppermost layer is the organic layer 26 and the water vapor permeability is high such as less than 1 × 10 ⁻⁴ [g / (m ² · day)]. As described above, even a slight damage to the inorganic layer 28 causes a large gas barrier property, that is, a reduction in performance. Therefore, the effect of having the intermediate layer 16 is very large.

In the packaging material 10 of the present invention, the material for forming the intermediate layer 16 is not limited, and is a material having a glass transition temperature higher than that of the heat welding layer 20 and higher than that of the organic layer 26 (sheet-like material (film)). ) Can be used in various ways.
As an example, the support 24 of the gas barrier film 12 is PET or PEN (polyethylene naphthalate), the organic layer 26 is a (meth) acrylic resin, and the inorganic layer 28 is a silicon compound such as silicon nitride. When the material is PE or PP, a PET film, a PEN film, a nylon film, or the like is suitably used as the intermediate layer 16.
The intermediate layer 16 is preferably formed of the same material as the support 24 as described above. Therefore, in this example, it is preferable to use a PET film as the intermediate layer 16 when the support 24 is PET, and to use a PEN film as the intermediate layer 16 when the support 24 is PEN.

As described above, in the packaging material 10 of the present invention, the glass transition temperature satisfies the relationship of “thermal welding layer 20 <support 24 and intermediate layer 16 <organic layer 26”.
Here, depending on the material constituting the layer (composition of the material constituting the layer), the glass transition temperature may not be present (the glass transition temperature may not be defined).
In the packaging material 10 of the present invention, when one or more of the intermediate layer 16, the heat welding layer 20, the support 24, and the organic layer 26 is used, the softening temperature is changed to the glass transition temperature. (Softening point Ts) or melting point (Tm) is used. If both the softening temperature and the melting point can be defined, the softening temperature is used.

Further, the thickness of the intermediate layer 16 is not limited, and a thickness capable of exerting an action of relaxing the shrinkage and movement of the above-described heat-welded layer 20 is appropriately selected according to the forming material of the intermediate layer 16. Good.
Here, as will be described in detail later, if the thickness from the first adhesive layer 14 to the heat-welding layer 20 is too thick, the gas barrier property of the packaging material 10 of the present invention is deteriorated.
Considering this point, the thickness of the intermediate layer 16 is preferably 20 μm or less, particularly preferably 15 to 8 μm.

The first adhesive layer 14 for bonding the intermediate layer 16 to the gas barrier film 12 is a layer made of a known adhesive, and all the adhesives that can bond the intermediate layer 16 to the gas barrier film 12 (organic layer 26) are used. Is possible. In consideration of the optical characteristics of the packaging material 10, an adhesive having excellent transparency is preferably used.
Moreover, there is no limitation in the thickness of the 1st adhesive bond layer 14, What is necessary is just to select suitably the thickness which can adhere | attach the intermediate | middle layer 16 on the gas barrier film 12 reliably.
Here, as described above, if the thickness from the first adhesive layer 14 to the heat welding layer 20 is too thick, the gas barrier property of the packaging material 10 of the present invention is deteriorated. Accordingly, the first adhesive layer 14 is preferably thin, and particularly preferably 10 μm or less.

As described above, the material for forming the heat welding layer 20 is basically the same material as the material for forming a packaging material such as an infusion bag to which the packaging material 10 of the present invention is thermally welded.
That is, if the packaging material to which the packaging material 10 is thermally welded is made of PE, the thermal welding layer 20 may be formed of a PE film, and if the packaging material to which the packaging material 10 is thermally welded is made of PP. The heat welding layer 20 may be formed of a PP film.

Moreover, there is no limitation also on the thickness of the heat welding layer 20, and according to the forming material of the heat welding layer 20, according to the shape, state, etc. of the packaging material to which the packaging material 10 of this invention is heat welded reliably. What is necessary is just to select the thickness which can be heat-welded suitably.
Here, as mentioned above, when the thickness from the 1st adhesive bond layer 14 to the heat welding layer 20 is too thick, the gas barrier property of the packaging material of this invention will fall. Considering this point, the thickness of the heat welding layer 20 is preferably 60 μm or less, and particularly preferably 50 to 10 μm.

As the second adhesive layer 18 for adhering the heat welding layer 20 to the intermediate layer 16, all the adhesives capable of adhering the heat welding layer 20 to the intermediate layer 16 can be used. Similarly, an adhesive having excellent transparency is preferably used.
In addition, the thickness of the second adhesive layer 18 is not limited, and a thickness capable of reliably bonding the heat welding layer 20 to the intermediate layer 16 may be appropriately selected.
Further, as described above, when the thickness from the first adhesive layer 14 to the heat welding layer 20 is too thick, the gas barrier property of the packaging material of the present invention is deteriorated. Therefore, the second adhesive layer 18 is preferably thin, and particularly preferably 10 μm or less.

As described above, if the thickness from the first adhesive layer 14 to the heat welding layer 20 is too thick, the gas barrier property of the packaging material 10 of the present invention is deteriorated.
That is, each layer from the first adhesive layer 14 to the heat welding layer 20 basically has no gas barrier property. Accordingly, moisture and oxygen penetrate from the end faces of these layers, and the penetrated moisture and the like enter the inside of the packaging material to which the packaging material 10 of the present invention is thermally welded. Therefore, if the thickness from the first adhesive layer 14 to the heat welding layer 20 is too thick, the amount of moisture and oxygen entering from this end face increases, and the gas barrier property of the packaging material 10 is greatly lowered.
In other words, if the thickness from the first adhesive layer 14 to the heat-welded layer 20 is too thick, the gas barrier properties such as the gas barrier film described in Patent Document 4 and the like are usually excellent, and the gas barrier property is excellent until the intermediate layer 16 is increased by one layer. The meaning of using the laminated gas barrier film 12 is lost.

Here, when the thickness from the 1st adhesive bond layer 14 to the heat welding layer 20 exceeds 100 micrometers, the fall of the gas barrier property by the water | moisture content which penetrate | invades from an end surface will become very large.
Therefore, in the packaging material 10 of the present invention, the thickness from the first adhesive layer 14 to the heat welding layer 20 is preferably 100 μm or less, more preferably 80 μm or less, and particularly preferably 60 μm or less.

The packaging material of the present invention has been described in detail above, but the present invention is not limited to the above-described embodiments, and various improvements and modifications may be made without departing from the scope of the present invention. Of course.

Hereinafter, the present invention will be described in more detail with reference to specific examples of the present invention.
[Example 1]
On the support 24, the gas barrier film 12 which has the organic layer 26 as an underlayer, the inorganic layer 28, and the organic layer 26 as an uppermost protective layer was produced.

As the support 24, a long PET film (Cosmo Shine A4300 manufactured by Toyobo Co., Ltd.) having a width of 1000 mm and a thickness of 100 μm was used.
It was 69 degreeC when the glass transition temperature of this support body 24 was measured by DSC (differential scanning calorimetry).

MEK (methyl ethyl ketone), TMPTA (manufactured by Daicel-Cytec), modified bisphenol A diacrylate (EBECRYL150, manufactured by Daicel-Cytech), surfactant (BYK378, manufactured by BYK Chemie Japan), and photopolymerization initiator (Ciba Chemicals) A paint for forming the organic layer 26 was prepared by adding Irg184).
The addition amount of the surfactant was 1% by mass in the concentration excluding the organic solvent (solid content concentration), and the addition amount of the photopolymerization initiator was 2% by mass in the concentration excluding the organic solvent (that is, in the solid content). 97% by mass of organic compound). The amount of the modified bisphenol A diacrylate added was 10% of TMPTA, and the solid content concentration of the coating was 15% by mass.

The prepared paint was applied to the surface of the support 24 with a die coater, dried with warm air, and then irradiated with ultraviolet rays to form an organic layer 26 having a thickness of 2 μm.
It was 250 degreeC when the glass transition temperature of the organic layer 26 was measured by the method similar to the support body 24. FIG.

On this organic layer 26, a silicon nitride layer as an inorganic layer 28 was formed to a thickness of 50 nm by CCP-CVD.
Silane gas (SiH ₄ ), ammonia gas (NH ₃ ), nitrogen gas (N ₂ ), and hydrogen gas (H ₂ ) were used as source gases. The supply amounts were 100 sccm for silane gas, 200 sccm for ammonia gas, 500 sccm for nitrogen gas, and 500 sccm for hydrogen gas. The film forming pressure was 50 Pa.
The plasma excitation power was 3000 W at a frequency of 13.5 MHz. During the formation of the inorganic layer 28, a bias power of 500 W was supplied from the back side of the support 24, and the temperature of the support 24 was adjusted to −20 ° C.

On the inorganic layer 28, an organic layer 26 having a thickness of 2 μm is formed in the same manner as described above, and the underlying organic layer 26, the inorganic layer 28, and the uppermost layer are formed on the support 24. A gas barrier film 12 having an organic layer 26 was produced.

The water vapor permeability [g / (m ² · day)] of the produced gas barrier film 12 was measured by a calcium corrosion method (a method described in JP-A-2005-283561). As a result, the water vapor transmission rate was 8 × 10 ⁻⁵ [g / (m ² · day)].

An adhesive (taken by Mitsui Chemicals, Takelac and Takenate) dissolved in ethyl acetate was applied to the surface of the gas barrier film 12 (surface organic layer 26) with a bar coater, dried at 80 ° C., and a first adhesive having a thickness of 4 μm. The agent layer 14 was formed.
A 12 μm-thick PET film (Lumirror manufactured by Toray Industries, Inc.) was laminated as the intermediate layer 16 on the first adhesive layer 14, and conveyed and bonded while being pressed / heated by a nip roll.
It was 69 degreeC when the glass transition temperature of the intermediate | middle layer 16 was measured by the method similar to the support body 24. FIG.

An adhesive was applied to the surface of the intermediate layer 16 in the same manner as the first adhesive layer 14 to form a second adhesive layer 18 having a thickness of 4 μm.
On top of that, a 40 μm thick PE film (FC-S40 manufactured by Tosero Co., Ltd.) is laminated as the heat-welded layer 20, transported while being pressed / heated with a nip roll, and bonded to form a package as shown in FIG. Material 10 was made.
The glass transition temperature of the heat-welded layer 20 was measured by the same method as that for the support 24 and found to be −25 ° C.

The produced packaging material 10 was cut into 100 × 100 mm and laminated on a PE film having the same size and a thickness of 40 μm. Next, the entire peripheral edge 10 mm of the packaging material 10 was heated and pressed from the support 24 side, and the packaging material 10 was thermally welded to the PE film.
When the water vapor transmission rate of the laminate of the heat-welded packaging material 10 and the PE film was measured in the same manner as described above, it was 1.0 × 10 ⁻⁴ [g / (m ² · day)].

[Example 2]
The same as in Example 1 except that the amount of the modified bisphenol A diacrylate was changed to 20% of TMPTA in the coating material for forming the organic layer 26 without changing the solid content concentration (15% by mass) of the coating material. A gas barrier film 12 was produced, and a packaging material 10 was further produced.
It was 140 degreeC when the glass transition temperature of the organic layer 26 was measured similarly to Example 1. FIG. Moreover, when the water vapor transmission rate of the produced gas barrier film 12 was measured in the same manner as in Example 1, it was 1.8 × 10 ⁻⁴ [g / (m ² · day)].
The produced packaging material 10 was heat-welded to a PE film in the same manner as in Example 1 and the water vapor permeability of the laminate was measured to find 1.9 × 10 ⁻⁴ [g / (m ² · day)]. there were.

[Example 3]
A packaging material 10 was produced in the same manner as in Example 1 except that the heat welding layer 20 was changed to a PE film (FC-S100 manufactured by Tosero Co., Ltd.) having a thickness of 100 μm.
When the glass transition temperature of the heat-welded layer 20 was measured in the same manner as in Example 1, it was −25 ° C.
The produced packaging material 10 was thermally welded to a PE film in the same manner as in Example 1, and the water vapor transmission rate of the laminate was measured to be 1.7 × 10 ⁻⁴ [g / (m ² · day)]. there were.

[Example 4]
A packaging material 10 was produced in the same manner as in Example 1 except that the intermediate layer 16 was changed to a PET film having a thickness of 100 μm (Cosmo Shine A4300 manufactured by Toyobo Co., Ltd.).
It was 69 degreeC when the glass transition temperature of the intermediate | middle layer 16 was measured similarly to Example 1. FIG.
The produced packaging material 10 was heat-welded to a PE film in the same manner as in Example 1, and the water vapor permeability of the laminate was measured to find 4.9 × 10 ⁻⁴ [g / (m ² · day)]. there were.

[Example 5]
A packaging material 10 was produced in the same manner as in Example 1 except that the heat-welded layer 20 was replaced with a 25 μm thick PE film (FC-S25 manufactured by Tosero).
When the glass transition temperature of the heat-welded layer 20 was measured in the same manner as in Example 1, it was −25 ° C.
The produced packaging material 10 was heat-welded to a PE film in the same manner as in Example 1 and the water vapor permeability of the laminate was measured. As a result, it was 9.8 × 10 ⁻⁵ [g / (m ² · day)]. there were.

[Comparative Example 1]
A packaging material 10 was produced in the same manner as in Example 1 except that the intermediate layer 16 was changed to a PE film having a thickness of 12 μm (Idemitsu New IP Stretch, manufactured by Idemitsu Unitech Co., Ltd.).
When the glass transition temperature of the intermediate layer 16 was measured in the same manner as in Example 1, it was −25 ° C.
The produced packaging material 10 was heat-welded to a PE film in the same manner as in Example 1, and the water vapor transmission rate of the laminate was measured to be 1.5 × 10 ⁻³ [g / (m ² · day)]. there were.

[Comparative Example 2]
A packaging material 10 was produced in the same manner as in Example 1 except that the intermediate layer 16 was changed to a 12 μm-thick polyimide film (Kapton 50H manufactured by Toray DuPont).
When the glass transition temperature of the intermediate layer 16 was measured in the same manner as in Example 1, the measurement limit (about 260 ° C.) was exceeded. That is, the glass transition temperature of this polyimide film is considered to be much higher than 250 ° C.
The produced packaging material 10 was heat-welded to a PE film in the same manner as in Example 1, and the water vapor transmission rate of the laminate was measured to find 1.2 × 10 ⁻³ [g / (m ² · day)]. there were.

[Comparative Example 3]
Instead of TMPTA, a coating material for forming the organic layer 26 is prepared using fatty acid-modified epoxy acrylate (EBECRYL 3702, manufactured by Daicel-Cytec), and the gas barrier film 12 is produced in the same manner as in Example 1, and further packaging Material 10 was made.
It was 56 degreeC when the glass transition temperature of the organic layer 26 was measured similarly to Example 1. FIG. Further, in the same manner as in Example 1, the water vapor permeability of the produced gas barrier film 12 was measured and found to be 5 × 10 ⁻³ [g / (m ² · day)].
The produced packaging material 10 was thermally welded to a PE film in the same manner as in Example 1, and the water vapor transmission rate of the laminate was measured to be 6.5 × 10 ⁻³ [g / (m ² · day)]. there were.

[Comparative Example 4]
A gas barrier film was prepared in the same manner as in Example 1 except that the gas barrier film had a two-layer structure of the base organic layer 26 and the inorganic layer 28 (without the uppermost organic layer 26). Produced.
Similarly to Example 1, the water vapor permeability of the produced gas barrier film was measured and found to be 1.8 × 10 ⁻³ [g / (m ² · day)].
The produced packaging material 10 was heat-welded to a PE film in the same manner as in Example 1, and the water vapor transmission rate of the laminate was measured to be 8.5 × 10 ⁻³ [g / (m ² · day)]. there were.

[Comparative Example 5]
A gas barrier film was prepared in the same manner as in Example 1 except that the gas barrier film had a two-layer structure of the underlying organic layer 26 and inorganic layer 28 (without the uppermost organic layer 26) (that is, the gas barrier film was compared). Same as Example 4).
A packaging material was produced in the same manner as in Example 1 except that this gas barrier film was used and the intermediate layer 16 was not provided.
The produced packaging material 10 was heat-welded to a PE film in the same manner as in Example 1 and the water vapor transmission rate of the laminate was measured to be 9.0 × 10 ⁻² [g / (m ² · day)]. there were.

[Comparative Example 6]
A packaging material was produced in the same manner as in Example 1 except that the intermediate layer 16 was not provided.
The produced packaging material 10 was thermally welded to a PE film in the same manner as in Example 1, and the water vapor transmission rate of the laminate was measured. As a result, it was 7.0 × 10 ⁻⁴ [g / (m ² · day)]. there were.

The above results are summarized in the following table.
In the table below, the water vapor transmission rate (barrier property) is
“Excellent” if less than 1 × 10 ^-4 [g / (m ²・ day)];
1 × 10 ⁻⁴ [g / (m ² · day)] or more and less than 2 × 10 ⁻⁴ [g / (m ² · day)] “good”;
Anything over 2 × 10 ^-4 [g / (m ² · day)] and less than 1 × 10 ^-3 [g / (m ² · day)] is acceptable.
1 × 10 ⁻³ [g / (m ² · day)] or more was evaluated as “impossible”;

As shown in the above table, the packaging material 10 of the present invention in which the glass transition temperature of each layer satisfies “thermal welding layer 20 <support 24 and intermediate layer 16 <organic layer 26” is heat-sealed with the PE film. However, it exhibits a high gas barrier property of less than 2.0 × 10 ⁻⁴ [g / (m ² · day)].
In particular, Example 5 in which the thickness of the heat-welded layer 20 is thinner than others has a very high gas barrier performance of less than 1 × 10 ⁻⁴ [g / (m ² · day)]. .
In Example 2, since the glass transition temperature of the organic layer 26 is low, Example 3 is thicker in the intermediate layer 16 than in Example 4, because the heat-welded layer 20 is thicker. It is considered that the gas barrier performance slightly decreased.
On the other hand, since the glass transition temperature of the intermediate layer 16 is the same as that of the heat welding layer 20 in the comparative example 1, the glass transition temperature of the intermediate layer 16 is higher than that of the organic layer 26 in the comparative example 2. Since the glass transition temperature of the intermediate layer 16 is higher than that of the organic layer 26 and the glass transition temperature of the organic layer 26 is low, both of the support layer 24 and the thermal welding are used in Comparative Example 3. The deformation of the layer 20 and the like is transmitted to the inorganic layer 28 and the inorganic layer 28 is damaged, and the gas barrier property is low as compared with the packaging material of the present invention. Furthermore, the comparative example 6 which does not have the intermediate | middle layer 16 also has low gas barrier property compared with the packaging material of this invention for the same reason.
Examples 1, 3, 4, and 5 and Comparative Examples 1, 2, and 6 all use the same gas barrier film 12. That is, in the comparative example, it is considered that the inorganic layer 28 is damaged during the thermal welding with the PE film, and the gas barrier property is lowered. On the other hand, according to the packaging material 10 of the present invention, it is possible to prevent the inorganic layer 28 from being damaged during the thermal welding with the packaging material.
In Comparative Examples 4 and 5 in which the gas barrier film has a two-layer structure of organic layer / inorganic layer, the gas barrier film itself has low gas barrier performance due to damage to the inorganic layer during handling and the like. Performance cannot be obtained.
From the above results, the effects of the present invention are clear.

It can be suitably used for medical infusion bags, food tubes and packaging bags.

DESCRIPTION OF SYMBOLS 10 Packaging material 12 Gas barrier film 14 1st adhesive bond layer 16 Intermediate | middle layer 18 2nd adhesive bond layer 20 Thermal welding layer 24 Support body 26 Organic layer 28 Inorganic layer

Claims (10)

1. A packaging material thermally welded to the packaging material,
   A gas barrier film, an intermediate layer bonded to the gas barrier film by a first adhesive layer, and a heat welding layer bonded to the intermediate layer by a second adhesive layer;
   The gas barrier film has a laminated structure in which one or more combinations of an inorganic layer having gas barrier properties and an organic layer serving as a base layer of the inorganic layer are formed on a support, and the uppermost layer is an organic layer. Have
   Further, the glass transition temperature of the organic layer is higher than the support of the intermediate layer and the gas barrier film, and the glass transition temperature of the support of the intermediate layer and the gas barrier film is higher than the heat welding layer. Packaging material to do.
2. The packaging material according to claim 1, wherein the thickness from the first adhesive layer to the heat-welded layer is 100 µm or less.
3. The packaging material according to claim 1 or 2, wherein the intermediate layer and the support for the gas barrier film are formed of the same material.
4. The packaging material according to any one of claims 1 to 3, wherein all the organic layers are formed of the same material.
5. The packaging material according to any one of claims 1 to 4, wherein the thickness of the heat welding layer is 60 µm or less.
6. The packaging material according to any one of claims 1 to 5, wherein the intermediate layer has a thickness of 20 µm or less.
7. The packaging material according to any one of claims 1 to 6, wherein the organic layer is a layer made of at least one of an acrylic resin and a methacrylic resin.
8. The packaging material according to any one of claims 1 to 7, wherein the inorganic layer is a layer made of silicon nitride.
9. The packaging material according to any one of claims 1 to 8, wherein the heat welding layer is a layer made of polyethylene or polypropylene.
10. The packaging material according to any one of claims 1 to 9, wherein the intermediate layer is a layer made of polyethylene terephthalate.

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