Packaging bag

Abstract

This packaging bag is provided with a bag main body that is provided with: a joining section in which a laminate having a sealing layer, an oxygen barrier layer, and a water vapor barrier layer in this order is superposed so that the sealing layer sides face each other, and the outer peripheral edge sections of the laminate are welded to each other; and a housing chamber which is defined by the laminate and the joining part and is filled with contents, and the water vapor barrier layer contains a fluorine-based resin.

Description

Technical Field

[0001] The invention relates to a packaging bag. Background Art

[0002] In various fields such as medicine, food, and cosmetics, bag-shaped packages are used as packages for filling contents such as medicines, food, and cosmetics. The packages are formed by overlapping laminates of multiple resin films and joining the peripheries by heat sealing or the like.

[0003] As such a packaging body, for example, a packaging bag formed using a gas barrier film is disclosed, wherein the gas barrier film has an oxygen barrier resin layer formed of a high hydrogen bonding resin containing an inorganic layered compound and a water vapor transmission rate of 20 g / (m 2 d) A gas barrier layer formed of the following water vapor barrier resin layer (for example, Patent Document 1).

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2015-36215 Summary of the Invention

[0005] However, in the packaging bag of Patent Document 1, the barrier properties may be reduced if the water vapor barrier resin layer absorbs water vapor. If water vapor passes through the water vapor barrier resin layer and reaches the oxygen barrier resin layer, the oxygen barrier resin layer absorbs water vapor, thereby reducing the oxygen barrier properties.

[0006] It is important for packaging bags to maintain low oxygen permeability and oxygen barrier properties until the contents are used so as to prevent degradation due to oxidation, and to maintain low water vapor permeability and water vapor barrier properties so as to prevent changes in the concentration of the contents.

[0007] An object of one embodiment of the present invention is to provide a packaging bag capable of maintaining oxygen barrier properties and water vapor barrier properties.

[0008] One embodiment of the present invention provides a packaging bag having a bag body, wherein the bag body includes:

[0009] a joining portion formed by overlapping a laminate having a sealant layer, an oxygen barrier layer, and a water vapor barrier layer in this order with the sealant layer sides facing each other and welding their outer peripheral edges together; and

[0010] The receiving chamber is defined by the stacked body and the joint and is filled with contents.

[0011] The water vapor barrier layer includes a fluorine-based resin.

[0012] According to one aspect of the present invention, a packaging bag capable of maintaining oxygen barrier properties and water vapor barrier properties can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a plan view of the packaging bag according to the first embodiment of the present invention.

[0014] Figure 2 It is along Figure 1 Cross-sectional view in direction II.

[0015] Figure 3 It is a cross-sectional view of a packaging bag according to a second embodiment of the present invention. DETAILED DESCRIPTION

[0016] The following describes the embodiments of the present invention in detail. It should be noted that, in order to facilitate understanding of the description, the same structural elements are marked with the same reference numerals in the drawings, and repeated descriptions are omitted. In addition, the scales of the components in the drawings may differ from the actual situation. Unless otherwise specified, the "to" indicating a numerical range in this specification means that the numerical values ​​recorded before and after it are included as the lower limit and upper limit.

[0017] <First embodiment>

[0018] [Packaging bag]

[0019] A packaging bag according to a first embodiment of the present invention will be described. Figure 1 is a plan view of a packaging bag according to this embodiment. Figure 2 It is along Figure 1 The cross-sectional view in the II direction. Figure 1 As shown, the packaging bag 1A according to this embodiment includes a bag body 10A and may include an infusion port 20 connected to the bag body 10A. The packaging bag 1A stores contents within the bag body 10A. It should be noted that in this embodiment, the packaging bag 1A consists of the bag body 10A and the infusion port 20, but may also include other components.

[0020] The contents may include pharmaceuticals (drugs), cells, tissues, organs, biological materials, blood, body fluids, enzymes, antibodies, beauty products, nutrients, health supplements, cosmetics, foods, etc. Among them, pharmaceuticals are preferred. As pharmaceuticals, for example, biopharmaceuticals can be preferably mentioned. As biopharmaceuticals, for example, protein preparations can be preferably mentioned.

[0021] The form of the contents is not particularly limited, and may be, for example, solid, liquid, gas, powder, granules, mixture, composition, dispersion, etc. When the contents are liquid, the liquid may be an aqueous solution containing the drug.

[0022] When the contents are accommodated in the bag body 10A, the bag body 10A may be filled with an inert gas such as nitrogen or a liquid.

[0023] Although the packaging bag 1A is a pouch, the shape of the packaging bag 1A is not particularly limited. For example, it can be a three-side sealed bag, a four-side sealed bag, a back-sealed bag, a gusseted bag, a stand-up bag, a bag-in-box liner, a bag-in-can, etc.

[0024] like Figure 2 As shown, the bag body 10A is formed of a pair of laminated bodies 11A, and is formed into a bag shape by overlapping the pair of laminated bodies 11A so as to face each other and bonding their outer peripheral edges to each other.

[0025] The bag body 10A includes a joined portion 101 formed by overlapping a pair of stacked bodies 11A facing each other and fusing their outer peripheral edges together, and a storage chamber 102 defined by the pair of stacked bodies 11A and the joined portion 101 .

[0026] The joint 101 is provided in a closed loop around the periphery of the bag body 10A. The joint 101 comprises a first joint 101-1, which joins the stacked body 11A to the infusion port 20, and a second joint 101-2, which joins the stacked bodies 11A to each other. When viewed from above the bag body 10A, the first joint 101-1 and the second joint 101-2 are formed continuously.

[0027] The storage chamber 102 is a space for filling the contents. It should be noted that the specific state and shape of the contents are not shown in the drawings. Before filling the contents, the bag body 10A may have a filling port, such as in a portion of the joint 101, for filling the storage chamber 102 with the contents.

[0028] (Laminated body)

[0029] like Figure 2 As shown, the laminate 11A includes a sealant layer 111, an oxygen barrier layer 112, and a water vapor barrier layer 113 laminated in this order. The bag body 10A is formed by placing the sealant layers 111 of a pair of laminates 11A facing each other and bonding the outer peripheral edges of the sealant layers 111 to each other.

[0030] ((Sealing layer))

[0031] The sealant layer 111 is used when the laminate 11A is bonded together to form a bag shape by heat sealing, etc. The sealant layer 111 is a layer facing the storage chamber 102 and in contact with the contents.

[0032] From the viewpoint of non-adsorption, the sealing layer 111 preferably contains a cyclic olefin-based resin.

[0033] Examples of cyclic olefin resins include cyclic olefin polymers (COP) and cyclic olefin copolymers (COC). The resin component constituting the sealant layer 111 may be one or more cyclic olefin resins, or a mixture of a cyclic olefin resin and other resins or elastomers.

[0034] Examples of COP include homopolymers of cyclic olefins, copolymers of two or more cyclic olefins, or hydrogenated products thereof. The COP is preferably a non-crystalline polymer, more preferably a ring-opening polymer of a cyclic olefin formed by metathesis or the like, or a hydrogenated product thereof. Compared to cyclic olefin copolymers, COPs have a higher proportion of alicyclic structures and exhibit excellent non-adsorption properties to the contents contained within the containment chamber 102.

[0035] Examples of COC include copolymers of one or more cyclic olefins and one or more acyclic olefins, or hydrogenated products thereof. The cyclic olefin copolymer is preferably a non-crystalline polymer, more preferably a copolymer of a cyclic olefin and ethylene, or hydrogenated products thereof.

[0036] The cyclic olefin used as a structural monomer of the cyclic olefin resin is an unsaturated hydrocarbon (olefin) having at least one ring structure. Examples include vinylcycloalkanes and their derivatives having cycloalkanes with 3 to 20 carbon atoms, monocyclic olefins with 3 to 20 carbon atoms and their derivatives, and cyclic olefins having a norbornene skeleton (norbornene-based monomers).

[0037] Examples of norbornene monomers include bicyclo[2.2.1]-2-heptene (norbornene) and its derivatives. Examples of derivatives include compounds having substituents such as alkyl groups, compounds having two or more unsaturated bonds such as norbornadiene, and compounds having three or more ring structures in which two ring structures constitute the norbornene skeleton. Examples of norbornene monomers having three or more ring structures include tricyclo[5.2.1.0 2,6 ]Decene (dihydrodicyclopentadiene), compounds formed by adding one or more cyclopentadiene molecules to norbornene or dihydrodicyclopentadiene by the Diels-Alder reaction (for example, tetracyclododecene, pentacyclopentadecene, hexacycloheptadecene, etc.), their hydrides, isomers with different double bond positions, alkyl-substituted products, etc.

[0038] Examples of the acyclic olefin used as a structural monomer of COC include α-olefins such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene, and olefins such as 3-decene and 3-dodecene.

[0039] The thickness of the sealant layer 111 is preferably 10 to 100 μm, more preferably 20 to 60 μm, and even more preferably 30 to 50 μm. If the thickness of the sealant layer 111 is 10 to 100 μm, the sealant layers 111 of the stack 11A can be bonded together by heat sealing or the like, thereby forming the stack 11A into a bag shape. It should be noted that the upper and lower limits of the thickness of the sealant layer 111 may be arbitrarily combined.

[0040] When the sealant layer 111 is made of a cyclic olefin resin, the water vapor transmission rate (water vapor permeability) of the bag body 10A tends to decrease as the sealant layer 111 becomes thicker. On the other hand, the sealant layer 111 tends to be more susceptible to rupture as the sealant layer 111 becomes thicker. When the sealant layer 111 is made of a cyclic olefin resin, a thickness of 20 to 60 μm can reduce the water vapor transmission rate and suppress a decrease in strength.

[0041] It should be noted that, in this specification, the thickness of the sealing layer 111 refers to the length in the direction perpendicular to the main surface of the sealing layer 111. The thickness of the sealing layer 111 may be, for example, measured at any location in a cross-section of the sealing layer 111, or may be measured at multiple locations and the average of these measured values. The definition of thickness below applies to other components in a similar manner.

[0042] ((Oxygen barrier layer))

[0043] The oxygen barrier layer 112 is provided between the water vapor barrier layer 113 and the sealing layer 111 .

[0044] Materials for forming the oxygen barrier layer 112 include ethylene-vinyl alcohol copolymer (EVOH) and vinylidene chloride. These materials can be used alone or in combination. The oxygen barrier layer 112 preferably comprises EVOH. By including EVOH in the oxygen barrier layer 112, the bag body 10A can have excellent mechanical strength and optical properties, while also having a low water vapor transmission rate.

[0045] The ethylene content of EVOH is not particularly limited, but is preferably 1% to 50%, more preferably 30% to 46%, and more preferably 32% to 44%, from the viewpoint of the oxygen barrier layer 112 exhibiting oxygen barrier properties.

[0046] When heat-sealing the pair of laminates 11A with the sealant layer 111, the sealant layer 111 must be heated until the resin contained therein melts. To prevent deformation and degradation of the laminate 11A, the heat-sealing heating temperature must be lower than the melting temperature of the resin contained in the oxygen barrier layer 112. Therefore, the type of resin contained in the sealant layer 111 is limited by the type of resin contained in the oxygen barrier layer 112. In the laminate 11A of this embodiment, a fluorine-based resin having a higher glass transition temperature Tg than the resins conventionally used for water vapor barrier layers is used, thereby broadening the options for materials for forming the sealant layer 111.

[0047] The oxygen permeability of the oxygen barrier layer 112 is preferably 15 cc / (m 2 ·24hrs·atm) or less. If the oxygen barrier property of the oxygen barrier layer 112 is 15cc / (m 2 The lower limit of the oxygen barrier property of the oxygen barrier layer 112 is not particularly limited and can be appropriately set to any thickness depending on the application of the packaging bag 1A.

[0048] The thickness of the oxygen barrier layer 112 only needs to be 15 μm or more. If the thickness of the oxygen barrier layer 112 is 15 μm or more, the oxygen permeability of the laminate 11A can be suppressed to 15 cc / (m 2 ·24hrs·atm) or less, and the laminate 11A can be formed into a bag shape. It should be noted that the upper limit of the thickness of the oxygen barrier layer 112 is not particularly limited and can be appropriately set to any thickness depending on the type of oxygen barrier layer 112, the purpose of the packaging bag 1A, etc.

[0049] The oxygen barrier layer 112 may be a single layer or may be a stack of two or more layers.

[0050] ((Water vapor barrier))

[0051] The water vapor barrier layer 113 is a layer exposed to the outside of the storage chamber 102 and contains a fluorine-based resin.

[0052] As fluorine-based resin, polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-hexafluoropropylene-perfluoroalkyl vinyl ether (EPA), tetrafluoroethylene-ethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), chlorotrifluoroethylene-ethylene copolymer (ECTFE) etc. can be enumerated.Wherein, preferred polychlorotrifluoroethylene (PCTFE).Above-mentioned resin can be used alone or in combination with two or more kinds.

[0053] The water vapor barrier layer 113 can be formed from commonly used materials as materials with water vapor barrier properties other than fluorine-based resins. Examples of materials with water vapor barrier properties other than fluorine-based resins include: metal foils such as aluminum foil; deposited layers containing inorganic materials such as aluminum, silicon dioxide, and aluminum oxide; and resin layers composed of polyolefin resins, ethylene-vinyl alcohol copolymer (EVOH), polyvinylidene chloride (PVDC), and fluorine-based resins. These materials can be used alone or in combination.

[0054] Examples of the olefin resin include polyethylene resins and cyclic olefin polymers, and examples of the polyethylene resin include polypropylene (PP), high-density polyethylene (HDPE), and linear low-density polyethylene (LLDPE).

[0055] The water vapor barrier layer 113 comprises a fluororesin, preferably PCTFE. By including a fluororesin in the water vapor barrier layer 113, the bag body 10A can have excellent mechanical strength and optical properties, a low water vapor transmittance, and can suppress a decrease in barrier properties due to water vapor absorption.

[0056] The water vapor barrier layer 113 is preferably formed of a resin having a melting point higher than the sealing temperature of the sealing layer 111. Since fluorine-based resins generally have a higher melting point than the resin used in the sealing layer 111, the water vapor barrier layer 113 containing a fluorine-based resin can function as a base material when the pair of laminates 11A are heat-sealed with the sealing layer 111, and the selection of materials for forming the sealing layer 111 can be broadened.

[0057] The thickness of the water vapor barrier layer 113 is preferably 10 to 100 μm, more preferably 15 to 80 μm, and even more preferably 20 to 60 μm. When the thickness of the water vapor barrier layer 113 is 10 to 100 μm, the laminate 11A can be easily formed into a bag shape.

[0058] The water vapor barrier layer 113 may be a single layer or may be a laminate of two or more layers.

[0059] (Other layers)

[0060] The laminate 11A may include other layers between or on the surface of any of the sealing layer 111, oxygen barrier layer 112, and water vapor barrier layer 113. The type of other layers can be appropriately selected, and examples thereof include reinforcing layers, light-shielding layers, printed layers, metal foils, and synthetic paper.

[0061] Examples of the reinforcing layer include reinforcing resin layers such as biaxially stretched polyethylene terephthalate (O-PET), biaxially stretched nylon (O-Ny), and biaxially stretched polypropylene (OPP).

[0062] The laminate 11A may have a printed layer or a coating layer on the surface (surface) 113 a of the water vapor barrier layer 113 opposite to the oxygen barrier layer 112 .

[0063] The printed layer can impart identification and design properties to the packaging bag 1A by printing ink on the surface 113 a of the water vapor barrier layer 113 .

[0064] The coating layer is used to protect the water vapor barrier layer 113 or other layers such as a printed layer provided on the water vapor barrier layer 113. Examples of such a coating layer include a thin film resin layer (resin film) and an ultraviolet curable resin layer.

[0065] As described above, the joint 101 is formed by stacking a pair of stacked bodies 11A facing each other and fusing the resin contained in the sealant layers 111 of the stacked bodies 11A. The joint 101 has a laminated structure of "water vapor barrier layer 113 / oxygen barrier layer 112 / sealant layer 111 / sealant layer 111 / oxygen barrier layer 112 / water vapor barrier layer 113" stacked in this order from the surface of one water vapor barrier layer 113 of the stacked bodies 11A toward the surface of the other water vapor barrier layer 113.

[0066] [Infusion port]

[0067] like Figure 2 As shown, the infusion port 20 is sandwiched and joined by the opposing sealing layers 111. The infusion port 20 preferably contains a cyclic olefin resin, and preferably contains a cyclic olefin resin in at least the portion that contacts the contents. As the cyclic olefin resin forming the infusion port 20, the same cyclic olefin resin as the cyclic olefin resin forming the sealing layer 111 can be cited. The material forming the infusion port 20 and the material forming the sealing layer 111 may be the same or different, but the infusion port 20 and the sealing layer 111 are preferably formed of the same material. It should be noted that the molded product may be a single-color molded product or a multi-color molded product such as a two-color molded product.

[0068] The infusion port 20 has a cylindrical shape and includes a flow path 201 for removing the contents. The infusion port 20 includes at least a portion housed within the storage chamber 102. The infusion port 20 is preferably formed from a cyclic olefin resin or a polyolefin resin, more preferably a cyclic olefin resin. If the infusion port 20 is formed from a cyclic olefin resin, it can exhibit excellent non-adsorptive properties toward the contents.

[0069] As polyolefin resin, it can be a homopolymer (homopolymer) of one olefin, or a copolymer (copolymer) of two or more olefins. As olefin, non-cyclic olefins such as ethylene, propylene, 1-butene, 1-hexene, 1-octene, α-olefins can be enumerated. As a specific example of polyolefin, polyethylene, polypropylene, ethylene-α-olefin copolymers etc. can be enumerated. These polyolefins can be copolymers of non-olefin vinyl monomers such as vinyl acetate, vinyl chloride, vinyl alcohol, etc. that contain a small amount of vinyl acetate. The source of olefin can be olefin from petroleum, olefin from plant, or a combination of the two.

[0070] When the polyolefin resin forming the infusion port 20 is polyethylene, linear low-density polyethylene (LLDPE) is preferably used as the polyethylene. When the infusion port 20 is formed of LLDPE, the laminate 11A forming the bag body 10A and the infusion port 20 can be easily joined, thereby improving the handleability and durability of the packaging bag 1A.

[0071] The first joint 101-1 is formed by fusing the sealant layer 111 of each of the pair of laminates 11A to the resin contained in the infusion port 20. In the first joint 101-1, the laminated structure of the joined portion between the laminate 11A and the infusion port 20 is, from the surface side of one water vapor barrier layer 113 of the laminate 11A toward the surface side of the other water vapor barrier layer 113, in the order: "water vapor barrier layer 113 / oxygen barrier layer 112 / sealant layer 111 / infusion port 20 / sealant layer 111 / oxygen barrier layer 112 / water vapor barrier layer 113."

[0072] like Figure 2 As shown, the stacked body 11A has a portion joined to the infusion port 20 at the first joint portion 101 - 1 .

[0073] The packaging bag 1A may also have accessories such as a pouring port, a stopper, a label, an opening handle, and a handle in addition to the pouring port 20. When the accessories are resin molded products, they may have the same structure as the pouring port 20 described above.

[0074] [Method for manufacturing packaging bags]

[0075] An example of a method for manufacturing the packaging bag 1A will be described. In the method for manufacturing the packaging bag 1A, a resin forming the raw material of the water vapor barrier layer 113, a resin forming the raw material of the oxygen barrier layer 112, and a resin forming the raw material of the sealant layer 111 are sequentially laminated to form the laminate 11A (a step of forming the laminate 11A).

[0076] The sealing layer 111 , the oxygen barrier layer 112 , and the water vapor barrier layer 113 can be laminated by a method such as dry lamination or extrusion lamination to form the laminate 11A.

[0077] Next, the stacked body 11A and the infusion port 20 are joined together (joining step).

[0078] First, with the sealing layers 111 of the stacked bodies 11A facing each other, the infusion port 20 is sandwiched between the stacked bodies 11A.

[0079] Next, the stacked body 11A and the infusion port 20 are joined to form the first joined portion 101 - 1 .

[0080] Next, the stacked bodies 11A are joined together to form the second joining portion 101 - 2 .

[0081] In this way, the packaging bag 1A is manufactured.

[0082] Thus, the packaging bag 1A has a bag body 10A, which includes a joint 101 and a receiving chamber 102. The water vapor barrier layer 113 contained in the laminate 11A constituting the bag body 10A contains a fluorine-based resin with a low water vapor permeability as a forming material. As a result, the water vapor barrier layer 113 can sufficiently reduce the water vapor permeability and can suppress the reduction of the barrier properties to water vapor (water vapor barrier properties). Therefore, the oxygen barrier layer 112 located inside the receiving chamber 102 of the water vapor barrier layer 113 can be suppressed from absorbing water vapor that has passed through the water vapor barrier layer 113. Therefore, the packaging bag 1A can maintain the oxygen permeability at a low level and maintain the barrier properties to oxygen (oxygen barrier properties), and can maintain the water vapor permeability at a low level and maintain the water vapor barrier properties.

[0083] The packaging bag 1A may contain EVOH in the oxygen barrier layer 112. This allows the oxygen barrier layer 112 to have a low oxygen permeability, and thus the packaging bag 1A can reliably exhibit oxygen barrier properties.

[0084] The packaging bag 1A can include PCTFE as the fluororesin contained in the water vapor barrier layer 113. Among fluororesins, PCTFE has a particularly low water vapor permeability and can suppress moisture absorption, maintaining water vapor barrier properties. Therefore, by using PCTFE as the fluororesin contained in the water vapor barrier layer 113, the packaging bag 1A can reliably suppress moisture absorption by the water vapor barrier layer 113, thereby more reliably suppressing a decrease in the water vapor barrier properties of the water vapor barrier layer 113 and the oxygen barrier properties of the oxygen barrier layer 112. Consequently, the packaging bag 1A can more reliably maintain both oxygen and water vapor barrier properties.

[0085] The packaging bag 1A can have a water vapor barrier layer 113 with a thickness of 10 μm to 100 μm. This allows the water vapor barrier layer 113 to impart flexibility to the packaging bag 1A and reduce the water vapor transmission rate. Consequently, the packaging bag 1A can exhibit water vapor barrier properties while being easily formed into a bag-like shape.

[0086] The packaging bag 1A can have an oxygen barrier layer 112 with a thickness of 15 μm or greater. This allows the oxygen barrier layer 112 to impart flexibility to the packaging bag 1A while keeping the oxygen permeability low. Consequently, the packaging bag 1A can exhibit oxygen barrier properties while being easily formed into a bag-like shape.

[0087] The packaging bag 1A includes an infusion port 20, which can be joined while being sandwiched between the opposing sealant layers 111 of a pair of opposed laminates 11A. This prevents water vapor and air from entering the storage chamber 102 from the outside through the gap between the infusion port 20 and the sealant layers 111, thereby maintaining the packaging bag 1A's water vapor and oxygen barrier properties. Furthermore, the infusion port 20, like the sealant layers 111, can be formed from a cyclic olefin resin such as COP or COC, further reliably improving the packaging bag 1A's ability to resist adsorption of contents.

[0088] As described above, the packaging bag 1A has the above-mentioned characteristics and can be suitably used as an infusion bag for storing medicines (drugs), nutrients, food and drink, medical containers, medical equipment, medical supplies, cosmetics, etc. and performing sterilization.

[0089] <Second embodiment>

[0090] A packaging bag according to a second embodiment of the present invention will be described. Figure 3 This is a cross-sectional view of the packaging bag according to the present embodiment, which is taken along Figure 1 The cross-sectional view in the II direction. Figure 3 As shown, the packaging bag 1B involved in this embodiment will Figure 1 The structure of the packaging bag 1A according to the first embodiment shown is that the laminated body 11A of the bag body 10A is changed to a laminated body 11B.

[0091] The laminate 11B includes an adhesive layer (adhesive resin layer) 114 between each of the sealant layer 111 , the oxygen barrier layer 112 , and the water vapor barrier layer 113 .

[0092] [Adhesive layer]

[0093] Adhesive layer 114 includes adhesive layer 114A disposed between sealant layer 111 and oxygen barrier layer 112, and adhesive layer 114B disposed between oxygen barrier layer 112 and water vapor barrier layer 113. Adhesive layer 114A and adhesive layer 114B may be formed of the same material or different materials.

[0094] The adhesive layer 114 is preferably a first adhesive layer comprising a polyethylene resin and a modified polyethylene resin, or a second adhesive layer comprising a polyethylene resin and a resin composition having an elastomer component and an epoxy group.

[0095] (First Adhesive Layer)

[0096] Examples of the polyethylene resin contained in the first adhesive layer include linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), medium-density polyethylene (MDPE), and high-density polyethylene (HDPE), with low-density polyethylene being preferred.

[0097] The modified polyethylene resin included in the first adhesive layer is a polyethylene resin modified with an unsaturated carboxylic acid or its derivative, and has an acid functional group such as a carboxyl group or a carboxylic anhydride group. The modified polyethylene resin included in the first adhesive layer is preferably a polyethylene resin modified with an acid.

[0098] Examples of the acid modification method include graft modification in which a polyethylene resin and an acid functional group-containing monomer are melt-kneaded in the presence of a radical polymerization initiator such as an organic peroxide or an aliphatic azo compound.

[0099] The polyethylene resin material before modification is not limited as long as it contains ethylene as a raw material monomer, and known polyethylene resins can be used as appropriate. Specifically, as polyethylene resins, in addition to the examples mentioned above, ethylene-α-olefin copolymers such as ethylene-propylene copolymers, ethylene-1-butene copolymers, ethylene-4-methyl-1-pentene copolymers, ethylene-1-hexene copolymers, and ethylene-1-octene copolymers; and ethylene-vinyl acetate copolymers, ethylene-(meth)acrylic acid copolymers, and ethylene-(meth)acrylate copolymers can be cited.

[0100] The acid functional group-containing monomer is a compound having an ethylenic double bond and a carboxyl group or a carboxylic anhydride group in the same molecule, and examples thereof include various unsaturated monocarboxylic acids, dicarboxylic acids, or anhydrides of dicarboxylic acids.

[0101] Examples of the acid-functional monomer having a carboxyl group (carboxyl-containing monomer) include α,β-unsaturated carboxylic acid monomers such as acrylic acid, methacrylic acid, maleic acid, nadic acid, fumaric acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, tetrahydrophthalic acid, and endo-bicyclo[2.2.1]-5-heptene-2,3-dicarboxylic acid (endic acid).

[0102] Examples of the acid functional group-containing monomer having a carboxylic acid anhydride group (carboxylic acid anhydride group-containing monomer) include unsaturated dicarboxylic acid anhydride monomers such as maleic anhydride, nadic anhydride, itaconic anhydride, citraconic anhydride, and nadic anhydride.

[0103] Among the components constituting the oxygen barrier layer 112 , these acid functional group-containing monomers may be used alone or in combination of two or more.

[0104] Among these, as the acid functional group-containing monomer, an acid functional group-containing monomer having an acid anhydride group is preferred, a carboxylic acid anhydride group-containing monomer is more preferred, and maleic anhydride is particularly preferred.

[0105] When part of the acid-containing functional group monomer used in the acid modification remains unreacted, it is preferred to use an acid-containing functional group monomer from which the unreacted acid-containing functional group monomer has been removed in advance in order to prevent a decrease in adhesive strength due to the unreacted acid-containing functional group monomer.

[0106] The modified polyethylene-based resin contained in the first adhesive layer is preferably maleic anhydride-modified polyethylene.

[0107] In the first adhesive layer, when the total amount of the polyethylene resin and the modified polyethylene resin is taken as 100% by mass, the lower limit of the ratio of the polyethylene resin to the total amount of the polyethylene resin and the modified polyethylene resin is preferably 10% or more, and more preferably 20% or more. Furthermore, the upper limit of the ratio of the polyethylene resin to the total amount of the polyethylene resin and the modified polyethylene resin is preferably 70% or less, and more preferably 60% or less. For example, the mixing ratio of the polyethylene resin to the modified polyethylene resin can be polyethylene resin:modified polyethylene resin = 20:80 to 60:40.

[0108] By using a mixed material of polyethylene resin and modified polyethylene resin in the oxygen barrier layer 112, the adhesion between the sealant layer 111, the oxygen barrier layer 112, and the water vapor barrier layer 113 is improved. Therefore, delamination in the oxygen barrier layer 112 can be suppressed.

[0109] (Second Adhesive Layer)

[0110] The second adhesive layer includes a resin composition containing a polyethylene resin, an elastomer component, and a component having an epoxy group.

[0111] The polyethylene resin contained in the second adhesive layer is the same as the polyethylene resin contained in the mixture of the polyethylene resin and the modified polyethylene resin. The polyethylene resin contained in the resin composition may be any of biomass polyethylene, petroleum-derived polyethylene, or a mixture thereof.

[0112] Among the polyethylene resins included in the second adhesive layer, the polyethylene resin in the resin composition is preferably polyethylene polymerized using a metallocene catalyst. Preferred examples include ethylene-α-olefin copolymers such as C4-LLDPE, C6-LLDPE, and C8-LLDPE, and long-chain branched polyethylene polymerized using a metallocene catalyst.

[0113] Polyethylene resins obtained by polymerization with metallocene catalysts tend to have a narrow molecular weight distribution. Therefore, it is believed that high adhesion can be achieved when used as adhesives because they contain less low-molecular-weight components that may hinder adhesion.

[0114] The density of the polyethylene resin in the resin composition is preferably 0.890 g / cm 3 Above 0.940g / cm 3 Below, more preferably 0.910 g / cm 3 Above 0.930g / cm 3 the following.

[0115] The content of the polyethylene resin in the resin composition is 55 to 90 parts by mass, preferably 60 to 80 parts by mass. If the content of the polyethylene resin is 90 parts by mass or less, the adhesiveness with the elastomer component described below is exerted, resulting in increased adhesion.

[0116] Examples of the elastomer component contained in the second adhesive layer include styrene-based elastomers, acrylic elastomers, polyurethane-based elastomers, and ester-based elastomers. However, the elastomer component does not include a component having an epoxy group as described below.

[0117] Among them, styrene-based elastomers are preferred, for example, block copolymers having a hard segment composed of polystyrene and a soft segment composed of polyethylene, polybutadiene, polyisoprene, etc. Examples of styrene-based polymers that can be used in styrene-based elastomers include aromatic olefin-aliphatic olefin copolymers such as styrene-butadiene copolymers, styrene-isoprene copolymers, and styrene-ethylene copolymers.

[0118] The styrene-based elastomer is preferably a styrene-ethylene-butylene-styrene copolymer (SEBS) obtained by hydrogenating a styrene-butylene-styrene copolymer (SBS) to completely ring-open the unsaturated bonds in the molecule.

[0119] The styrene content of the styrene-based elastomer is preferably 8% to 24% by mass, more preferably 10% to 20% by mass. A styrene content of 20% by mass or less can suppress curing of the resin and reduce a decrease in adhesiveness.

[0120] Specific examples of the elastomer component contained in the second adhesive layer include Dynaron from JSR Corporation, Tuftec H series from Asahi Kasei Corporation, and Kraton G Polymer from Kraton Polymer Co., Ltd.

[0121] The content of the elastomer component in the second adhesive layer is 10 to 45 parts by mass, preferably 20 to 40 parts by mass. If the content of the elastomer component is 45 parts by mass or less, a decrease in tensile strength during formation of the second adhesive layer can be suppressed, and a decrease in adhesive strength can be prevented.

[0122] The total amount of the polyethylene resin and the elastomer component is 100 parts by mass.

[0123] The component having an epoxy group contained in the second adhesive layer is preferably a component having an epoxy group and a vinyl group. The component having an epoxy group and a vinyl group is preferably a component having a 1,2-vinyl structure, and is preferably an epoxidized polybutadiene obtained by partially epoxidizing butadiene. Epoxidized polybutadiene obtained by partially epoxidizing 1,2-polybutadiene is particularly preferred.

[0124] Specific examples of the component having an epoxy group include liquid polybutadiene JP-100 and JP-200 manufactured by Nippon Soda Co., Ltd., and ADK CIZER BF-1000 manufactured by ADEKA Corporation.

[0125] The number average molecular weight of the component having an epoxy group is preferably 500 to 4000. When the number average molecular weight of the component having an epoxy group is 4000 or less, a decrease in adhesiveness due to being in a solid state at room temperature can be suppressed, and a decrease in adhesiveness can be prevented.

[0126] In the present embodiment, the number average molecular weight is a value in terms of polystyrene measured by GPC (gel permeation chromatography).

[0127] In the second adhesive layer, the content of the component having an epoxy group is 0.1 to 1.5 parts by mass, preferably 0.5 to 1.0 parts by mass, relative to 100 parts by mass of the total amount of the polyethylene resin and the elastomer component. When the content of the component having an epoxy group is 1.5 parts by mass or less, low-molecular-weight components in the resin composition that can hinder adhesion can be reduced.

[0128] In the second adhesive layer, the elastomer component and the component having an epoxy group have a common repeating unit and are compatible with each other. The elastomer component and the component having an epoxy group are preferably a combination of styrene elastomers or a combination of acrylic elastomers.

[0129] The resin composition of the second adhesive layer can be a mixture of a polyethylene resin, an elastomer component, and a component containing epoxy groups, each mixed in a specific ratio. The epoxy groups in the component containing epoxy groups are compatible with the fluorine component of the fluororesin, resulting in excellent adhesion to the fluororesin. The presence of epoxy groups also allows for adhesion to metal materials.

[0130] In the second adhesive layer, a polyethylene resin, an elastomer component, and an epoxy-containing component are mixed in specific ratios to form a so-called sea-island structure, with the polyethylene resin acting as the "sea" and the elastomer component acting as the "islands." Furthermore, by making the epoxy-containing component and the elastomer component compatible, the epoxy-containing component can be evenly dispersed throughout the resin composition. This is presumably due to the protection of the epoxy groups by the polyethylene resin and the elastomer component, which can suppress the ring-opening of the epoxy groups caused by moisture.

[0131] By using a mixed material of a polyethylene resin, an elastomer component, and a component having an epoxy group in the oxygen barrier layer 112, the adhesion between the sealant layer 111, the oxygen barrier layer 112, and the water vapor barrier layer 113 is improved. As a result, the laminate 11A is less likely to delaminate.

[0132] Thus, in the packaging bag 1B, by including the adhesive layer 114 in the laminate 11B of the bag body 10A, delamination between the sealant layer 111 , the oxygen barrier layer 112 , and the water vapor barrier layer 113 can be suppressed while maintaining oxygen barrier properties and water vapor barrier properties.

[0133] As described above, the embodiments have been described. However, the embodiments are provided as examples, and the present invention is not limited thereto. The embodiments described above can be implemented in various other forms, and various combinations, omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included within the scope and spirit of the invention and are included within the scope of the invention described in the claims and their equivalents.

[0134] Example

[0135] Hereinafter, the present embodiment will be described using examples, but the present embodiment is not limited to these examples.

[0136] <Production of Laminated Body (Laminated Film)>

[0137] [Example 1]

[0138] The sealant layer, oxygen barrier layer, water vapor barrier layer, and adhesive layer (AD) that constitute the laminate (laminated film) were formed using a cycloolefin polymer (COP), an ethylene-vinyl alcohol copolymer (designated "EVOH1," ethylene content: 32%), a polychlorotrifluoroethylene resin (PCTFE), and a maleic anhydride-modified polyethylene adhesive resin, respectively. Using a T-die multilayer film forming machine, the COP, AD, EVOH1, AD, and PCTFE were co-extruded to produce a laminated film. The sealant layer, adhesive layer, oxygen barrier layer, adhesive layer, and water vapor barrier layer were sequentially laminated to the thicknesses shown in Table 1.

[0139] [Example 2]

[0140] A laminated film was produced in the same manner as in Example 1 except that EVOH having an ethylene content different from that of EVOH 1 (referred to as "EVOH 2" in place of EVOH 1, ethylene content: 44%) was used as the oxygen barrier layer.

[0141] [Example 3]

[0142] A laminated film was produced in the same manner as in Example 2 except that the thickness of the sealing layer was changed to 16 μm.

[0143] [Example 4]

[0144] A laminated film was produced in the same manner as in Example 1 except that an aromatic polyamide resin (relative viscosity: 2.65, melt viscosity: 500 Pa·sec, water content: 300 ppm) obtained by polymerizing m-xylylenediamine and adipic acid was used instead of EVOH1 for the oxygen barrier layer.

[0145] [Example 5]

[0146] In Example 1, except that the resin forming the water vapor barrier layer was changed to COP and the thickness of the water vapor barrier layer was changed to the thickness shown in Table 1, the same operation as in Example 1 was carried out to produce a laminated film.

[0147] [Example 6]

[0148] A laminated film in which a sealant layer, an adhesive layer, and an oxygen barrier layer were laminated in this order was produced in the same manner as in Example 1 except that the laminated film consisted of three layers: a sealant layer, an adhesive layer, and an oxygen barrier layer.

[0149] [Example 7]

[0150] In Example 2, except that the resin forming the water vapor barrier layer was changed to COP and the thickness of the water vapor barrier layer was changed to the thickness shown in Table 1, the same operation as in Example 1 was carried out to produce a laminated film.

[0151] [Example 8]

[0152] A laminated film in which a sealant layer, an adhesive layer, and an oxygen barrier layer were laminated in this order was produced in the same manner as in Example 2 except that the laminated film consisted of three layers: a sealant layer, an adhesive layer, and an oxygen barrier layer.

[0153] Table 1 shows the type of material and thickness of each layer constituting the laminated film in each example.

[0154] <Evaluation>

[0155] The oxygen permeability and water vapor permeability of the laminated film of each example were measured to evaluate the oxygen barrier properties and water vapor barrier properties.

[0156] [Oxygen transmission rate]

[0157] Oxygen was allowed to permeate through the resulting laminated film using an oxygen permeability measuring apparatus at 40°C and 70% relative humidity using the electrolytic sensor method (Appendix A) of JIS K 7126-2:2006, "Plastics - Films and Sheets - Gas Permeability Test Methods - Part 2: Isobaric Method (Mocon Method)." The amount of oxygen permeating the laminated film (oxygen permeability) was measured using the electrolytic sensor method. The laminated film was positioned so that the sealing layer side served as the chamber side for oxygen introduction, allowing oxygen to permeate from the sealing layer side of the laminated film to the water vapor barrier layer side. Since oxygen permeates the laminated film, the oxygen permeability of the laminated film was considered the oxygen permeability of the package. Table 1 shows the results of the oxygen permeability measurements of the laminated film for each example.

[0158] [Water vapor transmission rate]

[0159] The water vapor permeability of the obtained laminated film is measured using an infrared sensor method (Mocon method). That is, according to the JIS K 7129-2008B method, a water vapor permeability measuring device is used, and water vapor is passed through the obtained laminated film under the conditions of a temperature of 40°C and a relative humidity of 100% RH. The amount of water vapor passing through the laminated film is detected by an infrared sensor, and the water vapor permeability is calculated. The laminated film is configured so that the water vapor barrier layer side becomes the cavity side for introducing water vapor, and water vapor is passed through the sealing layer side from the water vapor barrier layer side of the laminated film. Since water vapor can pass through the laminated film, the water vapor permeability of the laminated film is regarded as the water vapor permeability of the package. Table 1 shows the measurement results of the water vapor permeability of the laminated film of each example.

[0160] [Table 1]

[0161]

[0162] As shown in Table 1, the laminated film of Example 1 had lower oxygen permeability and water vapor permeability than the laminated films of Examples 5 and 6, and was superior in oxygen barrier properties and water vapor barrier properties. This is believed to be because the water vapor barrier layers of the laminated films of Examples 5 and 6 absorbed moisture, resulting in poorer moisture resistance than the laminated film of Example 1. Consequently, the oxygen barrier layer absorbed moisture, which in turn resulted in water vapor that passed through the water vapor barrier layer, resulting in a decrease in oxygen barrier performance.

[0163] The laminated films of Examples 2 to 4 had lower oxygen permeability and water vapor permeability than the laminated films of Examples 7 and 8, and were superior in oxygen barrier properties and water vapor barrier properties. This is believed to be because the water vapor barrier layers of the laminated films of Examples 7 and 8 absorbed moisture, resulting in poorer moisture resistance than the laminated films of Examples 2 to 4. Consequently, the oxygen barrier layers absorbed moisture, resulting in water vapor that passed through the water vapor barrier layers, and the oxygen barrier properties decreased.

[0164] Therefore, in the case of a package, if PCTFE is used in the water vapor barrier layer constituting the laminated film, degradation of the water vapor barrier layer and the oxygen barrier layer can be suppressed, and excellent water vapor barrier properties and oxygen barrier properties can be exhibited.

[0165] It should be noted that the aspects according to the embodiments of the present invention are as follows, for example.

[0166] <1> A packaging bag comprising a bag body, the bag body comprising: a joint portion formed by overlapping a laminate having a sealant layer, an oxygen barrier layer, and a water vapor barrier layer in this order with the sealant layer sides facing each other and the outer peripheral edges thereof welded to each other; and a receiving chamber defined by the laminate and the joint portion and filled with a content.

[0167] The water vapor barrier layer includes a fluorine-based resin.

[0168] <2> The packaging bag according to <1>, wherein the oxygen barrier layer comprises an ethylene-vinyl alcohol copolymer.

[0169] <3> The packaging bag according to <1> or <2>, wherein the fluorine-based resin contains polychlorotrifluoroethylene.

[0170] <4> The packaging bag according to any one of <1> to <3>, wherein the water vapor barrier layer has a thickness of 10 μm to 100 μm.

[0171] <5> The packaging bag according to any one of <1> to <4>, wherein the oxygen barrier layer has a thickness of 15 μm or more.

[0172] <6> The packaging bag according to any one of <1> to <5>, wherein the packaging bag has an infusion port joined to the bag body.

[0173] The infusion port is sandwiched and joined by the opposing sealing layers.

[0174] <7> The packaging bag according to any one of <1> to <6>, wherein the content is a medicine.

[0175] <8> The packaging bag according to any one of <1> to <7>, wherein the packaging bag is an infusion bag.

[0176] This application claims priority based on Japanese Patent Application No. 2023-42338 filed with the Japan Patent Office on March 16, 2023, and cites all the contents described in the said application.

[0177] (Explanation of Reference Numerals)

[0178] 1A, 1B: packaging bags

[0179] 10A, 10B: Bag body

[0180] 101: Joint

[0181] 101-1: First joint

[0182] 101-2: Second joint

[0183] 102: Containment Chamber

[0184] 11A, 11B: Laminated body

[0185] 111: Sealing layer

[0186] 112: Oxygen barrier layer

[0187] 113: Water vapor barrier layer

[0188] 114: Adhesive layer

[0189] 20: Infusion port

Claims

1. A packaging bag comprising a bag body, the bag body comprising: a joining portion formed by overlapping a laminate having a sealant layer, an oxygen barrier layer, and a water vapor barrier layer in this order with the sealant layer sides facing each other and welding their outer peripheral edges together; and The receiving chamber is defined by the stacked body and the joint and is filled with contents. The water vapor barrier layer includes a fluorine-based resin.

2. The packaging bag according to claim 1, wherein: The oxygen barrier layer comprises ethylene-vinyl alcohol copolymer.

3. The packaging bag according to claim 1, wherein: The fluorine-based resin includes polychlorotrifluoroethylene.

4. The packaging bag according to claim 1, wherein: The thickness of the water vapor barrier layer is 10 μm to 100 μm.

5. The packaging bag according to claim 1, wherein The thickness of the oxygen barrier layer is greater than 15 μm.

6. The packaging bag according to claim 1, wherein: The packaging bag has an infusion port connected to the bag body. The infusion port is sandwiched and joined by the opposing sealing layers.

7. The packaging bag according to claim 1, wherein: The contents are medicines.

8. The packaging bag according to claim 1, wherein: The packaging bag is an infusion bag.

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