JP4688009B2 - Packaging bag - Google Patents

Description

【００５８】
［比較試験］
（１） 弾性強度
テンシロン万能試験機を用いて、引張速度３００ｍｍ／ｍｉｎで得られる弾性率に試験片の総厚みを乗じて得る。
（２） 引裂き強度
テスター産業製引裂き試験機を用いて、引裂き速度３０００ｍｍ／ｍｉｎで測定した。
（３） 酸素透過度
ＭＯＤＥＲＮ ＣＯＮＴＲＯＬＳ社製ＯＸ−ＴＲＡＮ２／２０を用い２２℃−６０％ＲＨにて測定。
（４） 紫外線透過度
上記実施例１及び比較例１で得られたスタンディングパウチを用いパウチの分光透過率を日本分光社製Ｖ−５７０分光光度計を使用して測定した。
【００５９】
測定結果を図６に示す。図６において曲線Ａは実施例１，曲線Ｂは比較例１を示す。紫外線遮断性層を全く有さない比較例１のプラスチックフィルムは紫外領域及び可視領域の光をかなり透過する（曲線Ｂ）。これに対し紫外線遮断性層を設けた、本発明の実施例１のパウチでは紫外領域のみならず可視領域の光をも大幅に遮断し、優れた遮光性を有することが判る。
【００６０】
【発明の効果】
本発明によれば、積層フィルムからなる包装袋の引き裂き強度を小さい値に維持しながら、積層フィルムの剛性を高めることが可能となり、包装袋の引き裂きによる開封性を向上させながら、包装袋に要求される剛性（腰）を高めることが可能となる。
また、一定の剛性を得るのに必要なフィルムの厚みを低減できるので、包装袋の製造に必要なコストを低減できるとともに省資源及び廃棄物削減が可能にる。
さらに、ガスバリア層及び紫外線遮断性層を設けた構成としているため、内容物の酸化劣化及び紫外線劣化を防止することができる。
【図面の簡単な説明】
【図１】 本発明の包装袋を形成する積層フィルムの１例を示す模式断面図である。
【図２】本発明の包装袋を形成する積層フィルムの他の例を示す模式断面図である。
【図３】本発明の包装袋を形成する積層フィルムの他の例を示す模式断面図である。
【図４】本発明の包装袋の１例を示す図である。
【図５】内面フィルムについての弾性強度（ｋｇｆ／ｃｍ）と引き裂き強度（ｋｇｆ）との関係を示すグラフである。
【図６】 本発明の包装袋の紫外線透過曲線を示す。
【符号の説明】
１ 積層フィルム
２ 内面フィルム
３ 紫外線遮断性層
４ ガスバリア性薄膜層
５ 外面フィルム
６ 最内面層
７ 中間層
８ 接合層
９ プラスチックフィルム
１０ 包装袋
１１ 周縁部
１２ ヒートシール部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a packaging bag. More specifically, the present invention relates to a packaging bag that is excellent in a combination of tearing-opening property and rigidity, and further excellent in gas barrier properties and ultraviolet blocking properties.
[0002]
[Prior art]
Conventionally, packaging bags such as standing pouches containing oily foods, edible oils, cosmetics, liquid detergents, liquid bleaches, softeners, shampoos, rinses, beverages, etc., such as biaxially stretched plastic films and aluminum foil What laminated | stacked the inner surface film of the olefin resin on the base material is known.
[0003]
However, even in such a self-supporting package, a large number of back-and-forth or right-and-left folds were observed at the time of display at the store, and the self-supporting formability was not satisfactory.
[0004]
What improved this self-supporting shape, provided a wide seal part protruding in a triangle on the side seal part of the packaging bag (Japanese Patent Laid-Open No. 5-330561), and formed a constricted part on the side seal part of the packaging bag (Japanese Patent Laid-Open No. 7-232743) has been proposed.
[0005]
In particular, in the case of a packaging bag storing contents sensitive to oxygen and ultraviolet rays, a packaging bag in which an aluminum foil is laminated in a layer of the packaging bag is widely known.
[0006]
Further, JP-A-6-182924 discloses a light-shielding packaging material in which a base material, silicon oxide, a pigment-containing resin layer, and a sealant layer are sequentially laminated.
[0007]
[Problems to be solved by the invention]
However, there are some packaging bags such as standing pouches, such as self-supporting shape, gas barrier, light-shielding, and easy tearing and opening when opening from the consumer needs. Important performance is required. The present invention has solved many of these problems.
[0008]
[Means for Solving the Problems]
The present invention
“1. In a packaging bag made of a laminated film, the inner film (a) of the laminated film is an innermost layer of an ethylene / butene-1 copolymer produced using a metallocene catalyst, an ethylene / butene-1 copolymer. And an inner surface film of the following formula (1) : and an intermediate layer of ethylene / hexene-1 copolymer bonding layer
T <0.0969 × E + 0.4 (1)
In the formula, T is the tear strength (kgf) of the inner film, and E is the elastic strength (kgf / cm 2) of the inner film, that is, the elastic modulus (kgf / cm ² ) of the film and the thickness (cm) of the film. A polyethylene-based resin film layer satisfying a product,
(B) an ultraviolet blocking layer;
(C) a gas barrier thin film layer;
(D) A packaging bag having at least a four-layer structure in which an outer film layer is laminated.
2. 2. The packaging bag according to 1 above, wherein the ultraviolet blocking layer (b) is a light blocking ink layer.
3. That the gas barrier thin film layer (c) is deposited (1) a metal or metal oxide or an inorganic oxide, (2) organic, inorganic coating, above, characterized in that a thin film layer made of both (3) The packaging bag according to 1 or 2 .
4). That the gas barrier thin film layer (c) is deposited (1) a metal or metal oxide or an inorganic oxide, (2) organic, inorganic coating, above, characterized in that a thin film layer made of both (3) The packaging bag in any one of 1-3 . ".
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The laminated film constituting the packaging bag of the present invention will be described in detail below based on the drawings.
[0010]
FIG. 1 is a schematic cross-sectional view showing an example of a laminated film constituting the packaging bag of the present invention. In FIG. 1, reference numeral 1 is a laminated film, reference numeral 2 is an inner film, reference numeral 3 is an ultraviolet blocking layer, reference numeral 4 is a gas barrier thin film layer, reference numeral 5 is an outer film layer, reference numeral 6 is an innermost layer of the inner film, reference numeral Reference numeral 7 denotes an intermediate layer of the inner film, and reference numeral 8 denotes a bonding layer of the inner film.
[0011]
FIG. 2 is a schematic cross-sectional view showing another example of a laminated film constituting the packaging bag of the present invention. In this example, the structure is the same as the laminated film of FIG. 1 except that the plastic film 9 is interposed between the inner film 2 and the ultraviolet blocking layer 3.
[0012]
FIG. 3 is a schematic cross-sectional view showing another example of a laminated film constituting the packaging bag of the present invention. In this example, the structure is the same as that of the laminated film of FIG. 1, except that the plastic film 9 is interposed between the ultraviolet blocking layer 3 and the gas barrier thin film layer 4.
FIG. 4 is a diagram showing an example of the packaging bag of the present invention.
[0014]
FIG. 5 is a graph showing the relationship between elastic strength (kgf / cm) and tear strength (kgf) for the inner surface film.
[0015]
FIG. 6 shows an ultraviolet transmission curve of the packaging bag of the present invention.
[0016]
More specifically, the inner film forming the innermost layer of the body portion is made of a polyethylene resin film, and this inner film is represented by the following formula (1).
T <0.0969 × E + 0.4 (1)
In the formula, T is the tear strength (kgf) of the inner film, and E is the elastic strength (kgf / cm 2) of the inner film, that is, the elastic modulus (kgf / cm ² ) of the film and the thickness (cm) of the film. Is the product.
It is a feature that the film is a polyethylene resin film satisfying the above, and this feature makes it possible to improve the rigidity of the laminated film while maintaining the tear strength of the laminated film in a low range.
[0017]
From these plots, the elastic strength (kgf / cm) and tear strength (kgf) of the polyethylene-based resin film are linearly related, and the tear strength (kgf) increases as the elastic strength (kgf / cm) increases. Can be seen from FIG.
[0018]
Moreover, since the elastic strength (kgf / cm) is a product of the elastic modulus (kgf / cm ² ) of the film and the thickness (cm) of the film, as described above, after all, when the thickness of the film increases, It shows that the tear strength of the film increases linearly.
[0019]
The packaging bag of the present invention comprises a laminated film, and uses a polyethylene-based resin film as its inner film, but may be a single layer film or a multilayer film as long as it has strength characteristics defined by the above formula (1). The chemical composition and the like are not particularly limited.
[0020]
Generally, it is not easy to obtain a polyethylene resin alone having the strength characteristics of the above formula (1), so a combination of two or more polyethylene resins or a combination with a modifying olefin resin. It is appropriate to use
[0021]
In this case, it is desirable that the thickness of the inner film is generally in the range of 20 to 200 μm, particularly 50 to 150 μm. If the thickness is less than the above range, the heat sealing workability is lowered or the waist of the final packaging bag is lowered. On the other hand, if the thickness exceeds the above range, the tearability tends to decrease, which is not preferable.
[0022]
In the packaging bag of this invention, as shown in FIG.1 and FIG.2, as the inner surface film 2 of linear low density polyethylene, this linear low density polyethylene inner surface film 2 was manufactured by using the metallocene catalyst. A laminated structure of an innermost surface layer 6 of butene-1 copolymer, an intermediate layer 7 of ethylene / butene-1 copolymer, and a bonding layer 8 of ethylene / hexene-1 copolymer is preferable.
[0023]
By using a laminate of linear low density polyethylene copolymerized with different α-olefins and linear low density polyethylene having different densities, the inner film 2 has excellent sealing properties, tear-opening properties, and environmental stress crack resistance. It is possible to achieve a combination of self-supporting shape retention and excellent standing characteristics and standing pouches.
[0024]
In the inner surface film 2 of the packaging bag of the present invention, it is this specific linear shape that uses an ethylene / butene-1 copolymer produced using a metallocene catalyst as the innermost layer surface (heat seal layer) 6. The low density polyethylene has not only good heat sealability but also good tear tearability, and is particularly suitable for the innermost layer.
[0025]
The reason why the ethylene / hexene-1 copolymer is used as the bonding layer 8 to be laminated with another layer is that it is excellent in laminate strength with other layers and is excellent in flexibility.
[0026]
That is, when sufficient laminate strength is not obtained between the other layer and the linear low density polyethylene inner layer film 2, the opening direction by tearing is shifted between the tearing direction of the substrate and the tearing direction of the inner film. May tend to occur, which may result in loss of tearing lightness.
[0027]
On the other hand, when the laminate strength of both films is high, the tear start points coincide with each other and are fixed at one point, and the film is easily torn.
[0028]
Further, an ethylene / butene-1 copolymer is interposed as the intermediate layer 7 between the innermost surface layer 6 and the bonding layer 8 because the intermediate layer 7 is required to have a self-supporting shape required for a standing pouch or the like. Moreover, it is because it is excellent in tearing openability.
[0029]
The resin of the innermost surface layer 6 of the inner surface film 2 preferably has a density in the range of 0.860 to 0.925 g / cc in terms of heat sealability and tear openability, and this density is outside the above range. Then, there exists a tendency for heat sealability and tear openability to worsen.
[0030]
The resin used for the intermediate layer 7 preferably has a density greater than the density of the innermost surface layer resin, particularly 0.02 g / cc or more higher than the density of the resin of the innermost surface layer 6.
[0031]
The resin of the intermediate layer 7 preferably has a density in the range of 0.91 to 0.95 g / cc from the standpoint of the self-supporting shape required for a standing pouch and the like, and the tear openability. If it is less than 1, the self-supporting shape retention property is lowered, and if it is more than the above range, the tear opening property tends to be lowered.
[0032]
Further, in order to improve the tear-opening property, the intermediate layer 7 is made of a high-density polyethylene or a low content of 0.1 to 80% by weight, preferably 5 to 50% by weight with respect to the ethylene / butene-1 copolymer. Density polyethylene may be blended. If the proportion of the high density polyethylene or the low density polyethylene is less than 0.1% by weight, substantially no further improvement in tear-opening property is observed, and if it exceeds 80% by weight, the drop strength decreases.
[0033]
The resin of the bonding layer 8 has a density smaller than the density of the resin of the intermediate layer 7, particularly a density of 0.01 g / cc or more smaller than the density of the resin of the intermediate layer 7, and the density of the resin of the innermost layer 6. It is preferable to have a density greater than.
[0034]
In general, the resin of the bonding layer 8 preferably has a density in the range of 0.90 to 0.935 g / cc from the viewpoint of laminate strength, flexibility, and moldability. When the laminate strength decreases and exceeds the above range, the flexibility tends to decrease.
[0035]
The thickness ratio of each layer in the inner surface film 2 composed of the laminated structure is 10 to 45%, particularly 15 to 40% for the innermost surface layer 6, 10 to 80% for the intermediate layer 7, particularly 20 to 70%, and the bonding layer 8 It is preferable to be in the range of 10 to 45%, particularly 15 to 40%.
[0036]
When the thickness ratio of the innermost layer 6 is below the above range, the heat sealability tends to be reduced, and when the intermediate layer 7 is below the above range, the waist (rigidity) of the inner surface film tends to be reduced, and further bonding When the layer 8 is less than the above range, the laminate strength of the inner surface film is lowered.
[0037]
When the thickness ratio of each layer of the inner surface film 2 is in the above range, the most excellent tear-opening property and balance of each property can be obtained.
[0038]
The production of the inner surface film 2 composed of a laminated structure by coextrusion is performed by using an extruder corresponding to the type of each resin layer, superposing the melt of each resin in a multilayer multiple die, and extruding this from a die orifice. Done.
[0039]
The packaging bag of the present invention may be a single layer film. As described above, it is appropriate to use a combination of two or more kinds of polyethylene resins or a combination with a modifying olefin resin as described above.
[0040]
These inner surface film materials can be formed into a film in advance by a T-die method, an inflation film forming method, etc., and can be used for lamination with a base material, or can be extrusion coated on a base material in the form of a molten web. You can also.
[0041]
The ultraviolet blocking layer 3 is formed on the next layer of the body portion. A particularly preferable ultraviolet blocking layer 3 is a light blocking ink layer. Preferred ink compositions used for the light-shielding ink layer include, for example, those containing fine particle ferric oxide pigments having a particle size of 200 μm or less, or fine particle titanium oxide pigments and ferric oxide pigments. The thing containing is mentioned.
[0042]
The light-shielding ink layer is formed on the gas barrier thin film layer 4 formed on the outer film 5 so that the layer thickness is 0.1 to 50 μm, preferably 1 to 20 μm, by a normal printing method or coating method. It is formed by printing or coating. When the thickness of the light-shielding ink layer is thin, sufficient light-shielding properties cannot be obtained, and when the layer thickness is too thick, the transparency is lowered.
[0043]
As another ultraviolet blocking layer 3, a polyethylene naphthalate film or a copolymerized polyester film containing naphthalene dicarboxylic acid can be used. These films can be laminated on the gas barrier thin film layer 4 formed on the outer film 5 by a dry laminating method.
[0044]
Further, a gas barrier thin film layer 4 is formed in a layer next to the body portion. Examples of the gas barrier thin film layer 4 include a vapor-deposited layer of an inorganic oxide such as aluminum oxide and silicon oxide formed on the outer surface film 5 and a coating film made of an organic substance or both.
[0045]
Furthermore, the outer surface film 5 is formed in the next layer. The plastic film to be used is not particularly limited, but it is desirable to use a film having mechanical strength, for example, a polyester film such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, ethylene terephthalate / isophthalate copolymer, Examples thereof include polyamide films such as nylon 6, nylon 6,6, nylon 11, nylon 12, nylon 6 / nylon 6,6 copolymer. These films are used as uniaxially or biaxially stretched films.
[0046]
Among the above stretched films, the biaxially stretched polyethylene terephthalate film is a material excellent in mechanical strength, crack resistance, and heat resistance, and thus is particularly suitable as an outer surface film of a packaging bag for storing contents having retort sterilization. Yes. However, since it is inferior in impact resistance and pinhole resistance, when a biaxially stretched polyethylene terephthalate film is used as an outer film, it is usually a plastic film such as a nylon film that can compensate for this point in addition to the inner film. And a laminated bag using the laminated film.
[0047]
On the other hand, stretched nylon film is excellent in gas barrier properties and barrier properties against fragrance components, but it is sensitive to humidity components and the barrier properties due to moisture absorption are reduced, so the outer surface of a packaging bag that contains contents that do not require retort sterilization Suitable as a film.
[0048]
The laminated film forming the packaging bag of the present invention is excellent in impact strength and piercing strength between the inner film 2 and the ultraviolet blocking layer 3 or between the ultraviolet blocking layer 3 and the gas barrier thin film layer 4. Alternatively, a layer structure in which a plastic film 9 is interposed may be employed. The reason why one more layer of this plastic film 9 is interposed is to make up for the strength that is practically insufficient with only the inner surface film 2 and the outer surface film 5, for example, the insufficient strength such as impact strength and piercing strength as a laminated film. Examples of the plastic film include polyamide films such as nylon 6, nylon 6,6, nylon 11, nylon 12, nylon 6 / nylon 6,6 copolymer. These films may be formed by any of the biaxial stretching method, the sequential stretching method, and the inflation method.
[0049]
The packaging bag of the present invention can be used as a packaging bag of various forms, and the bag making can be carried out by a known bag making method per se, such as ordinary pouches with three- or four-side seals, pouches with gussets. , Standing pouches, pillow packaging bags, and the like, but are not limited to this example.
[0050]
【Example】
EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further in detail, the following specific examples do not limit this invention.
Example 1
As the inner film 2, the innermost layer 6 is an ethylene / butene-1 copolymer having a density of 0.910 g / cc, the intermediate layer 7 is an ethylene / butene-1 copolymer having a density of 0.935 g / cc, and the bonding layer 8 is An ethylene / hexene-1 copolymer having a density of 0.920 g / cc was coextruded to prepare a three-layer coextruded polyethylene resin film having a thickness of 70 μm. At this time, the thickness ratio of each layer was 25%: 50%: 25%. Separately, on the thin film layer 4 of a film (trade name “MOS film NO” manufactured by Oike Kogyo Co., Ltd.) in which an inorganic oxide thin film layer 4 is formed on a biaxially stretched nylon film to be the outer film 5. A film on which a gravure ink (“New Lp Super V White” manufactured by Toyo Ink Manufacturing Co., Ltd.) in which fine particle titanium oxide and ferric oxide are dispersed is printed to form an ultraviolet blocking layer 3 having a thickness of 10 μm. Created. A laminated film 1 was prepared by laminating the ultraviolet blocking layer 3 surface of this film and the bonding layer 8 surface of the inner film 2 by a dry laminating method. Using this laminated film 1, the peripheral portion 11 was heat-sealed by a conventional method, and a standing pouch 10 shown in FIG. 4 was created. A gusset member constituting the bottom portion is attached to the lower side of the pouch by a heat seal portion 12.
[0051]
(Example 2)
A three-layer coextruded polyethylene film similar to Example 1 was prepared as the inner film 2 except that the thickness was 120 μm. Separately from this, a thin film of a film (trade name “GL-AE” manufactured by Toppan Printing Co., Ltd.) in which a thin film layer 4 made of an inorganic oxide and a metal oxide is formed on a biaxially stretched polyethylene terephthalate film to be the outer film 5. A gravure ink (“New Lp Super V White” manufactured by Toyo Ink Manufacturing Co., Ltd.) in which fine particle titanium oxide and ferric oxide are further dispersed is printed on the layer 4 to form an ultraviolet blocking layer 3 having a thickness of 10 μm. A laminated film 1 was prepared by dry laminating the ultraviolet blocking layer 3 of this film and the bonding layer 8 surface of the inner film 2.
[0052]
(Example 3)
A laminated film similar to that of Example 2 was prepared except that a biaxially stretched nylon film was laminated between the ultraviolet blocking layer 3 and the inner film 2 by a dry lamination method.
[0053]
Example 4
A laminated film similar to Example 2 was prepared except that a biaxially stretched nylon film was laminated between the thin film layer 4 made of an inorganic oxide and a metal oxide and the ultraviolet blocking layer 3 by a dry lamination method.
[0054]
(Example 5)
A 150 μm-thick single-layer film in which a linear low-density polyethylene made of an ethylene / butene 1 copolymer having a density of 0.915 g / cc and a low-density polyethylene having a density of 0.921 g / cc are blended in an amount of 70:30. A laminated film similar to Example 1 was prepared except that.
[0055]
(Comparative Example 1)
A standing pouch was prepared using the same laminated film as in Example 1 except that the ultraviolet blocking layer 3 was not formed.
[0056]
(Comparative Example 2)
A standing pouch was prepared using the same laminated film as in Example 1 except that the gas barrier thin film layer 4 was not formed.
[0057]
[Table 1]

[0058]
[Comparison test]
(1) Elastic strength Using a Tensilon universal tester, the elastic modulus obtained at a tensile speed of 300 mm / min is multiplied by the total thickness of the test piece.
(2) Tear strength tester Using a tear tester manufactured by Sangyo Sangyo, the tear strength was measured at a tear rate of 3000 mm / min.
(3) Oxygen permeability Measured at 22 ° C.-60% RH using OX-TRAN 2/20 manufactured by MODERN CONTROLS.
(4) Ultraviolet Transmittance Using the standing pouch obtained in Example 1 and Comparative Example 1, the spectral transmittance of the pouch was measured using a V-570 spectrophotometer manufactured by JASCO Corporation.
[0059]
The measurement results are shown in FIG. In FIG. 6, curve A shows Example 1, and curve B shows Comparative Example 1. The plastic film of Comparative Example 1 having no ultraviolet blocking layer transmits a large amount of light in the ultraviolet region and visible region (curve B). On the other hand, it can be seen that the pouch of Example 1 of the present invention provided with an ultraviolet blocking layer significantly blocks not only the ultraviolet region but also the light in the visible region and has an excellent light blocking property.
[0060]
【The invention's effect】
According to the present invention, it becomes possible to increase the rigidity of the laminated film while maintaining the tear strength of the packaging bag made of the laminated film at a small value, and the packaging bag is required to improve the openability by tearing the packaging bag. It is possible to increase the rigidity (waist).
In addition, since the film thickness required to obtain a certain rigidity can be reduced, the cost required for manufacturing the packaging bag can be reduced, and resource saving and waste reduction can be achieved.
Furthermore, since the gas barrier layer and the ultraviolet ray blocking layer are provided, the contents can be prevented from being oxidized and ultraviolet rays.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view showing an example of a laminated film forming a packaging bag of the present invention.
FIG. 2 is a schematic cross-sectional view showing another example of a laminated film forming the packaging bag of the present invention.
FIG. 3 is a schematic cross-sectional view showing another example of a laminated film forming the packaging bag of the present invention.
FIG. 4 is a view showing an example of a packaging bag according to the present invention.
FIG. 5 is a graph showing the relationship between elastic strength (kgf / cm) and tear strength (kgf) for an inner film.
FIG. 6 shows an ultraviolet transmission curve of the packaging bag of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Laminated film 2 Inner surface film 3 Ultraviolet ray blocking layer 4 Gas barrier thin film layer 5 Outer surface film 6 Outermost surface layer 7 Middle layer 8 Bonding layer 9 Plastic film 10 Packaging bag 11 Peripheral part 12 Heat seal part

Claims (4)

In a packaging bag made of a laminated film, the inner film (a) of the laminated film is an innermost layer of an ethylene / butene-1 copolymer produced using a metallocene catalyst, and an intermediate layer of the ethylene / butene-1 copolymer. , And a laminated structure of a joining layer of ethylene / hexene-1 copolymer, and the inner film has the following formula (1)
T <0.0969 × E + 0.4 (1)
In the formula, T is the tear strength (kgf) of the inner film, and E is the elastic strength (kgf / cm 2) of the inner film, that is, the elastic modulus (kgf / cm ² ) of the film and the thickness (cm) of the film. A polyethylene-based resin film layer satisfying a product,
(B) an ultraviolet blocking layer;
(C) a gas barrier thin film layer;
(D) A packaging bag having at least a four-layer structure in which an outer film layer is laminated. The packaging bag according to claim 1, wherein the ultraviolet blocking layer (b) is a light blocking ink layer. The gas barrier thin film layer (c) is a thin film layer comprising (1) a metal or metal oxide or inorganic oxide deposited, (2) an organic or inorganic coating, and (3) both. Item 3. A packaging bag according to item 1 or 2 . The gas barrier thin film layer (c) is a thin film layer comprising (1) a metal or metal oxide or inorganic oxide deposited, (2) an organic or inorganic coating, and (3) both. Item 4. The packaging bag according to any one of Items 1 to 3 .

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